/* Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

/*
  This file is included by both libmysql.c (the MySQL client C API)
  and the mysqld server to connect to another MYSQL server.

  The differences for the two cases are:

  - Things that only works for the client:
  - Trying to automaticly determinate user name if not supplied to
    mysql_real_connect()
  - Support for reading local file with LOAD DATA LOCAL
  - SHARED memory handling
  - Prepared statements
  - Things that only works for the server

  In all other cases, the code should be idential for the client and
  server.
*/ 

#include <my_global.h>
#include "mysql.h"
#include "hash.h"
#include "mysql/client_authentication.h"

/* Remove client convenience wrappers */
#undef max_allowed_packet
#undef net_buffer_length

#ifdef EMBEDDED_LIBRARY

#undef MYSQL_SERVER

#ifndef MYSQL_CLIENT
#define MYSQL_CLIENT
#endif

#define CLI_MYSQL_REAL_CONNECT STDCALL cli_mysql_real_connect

#undef net_flush
my_bool	net_flush(NET *net);

#else  /*EMBEDDED_LIBRARY*/
#define CLI_MYSQL_REAL_CONNECT STDCALL mysql_real_connect
#endif /*EMBEDDED_LIBRARY*/

#include <my_sys.h>
#include "my_default.h"
#include <mysys_err.h>
#include <m_string.h>
#include <m_ctype.h>
#include "mysql_version.h"
#include "mysqld_error.h"
#include "errmsg.h"
#include <violite.h>

#if !defined(_WIN32)
#include <my_pthread.h>				/* because of signal()	*/
#endif /* !defined(_WIN32) */

#include <sys/stat.h>
#include <signal.h>
#include <time.h>

#ifdef	 HAVE_PWD_H
#include <pwd.h>
#endif

#ifdef HAVE_SYS_SELECT_H
#  include <sys/select.h>
#endif

#ifdef HAVE_SYS_UN_H
#  include <sys/un.h>
#endif

#ifndef _WIN32
#include <errno.h>
#define SOCKET_ERROR -1
#endif

#include "client_settings.h"
#include <sql_common.h>
#include <mysql/client_plugin.h>
#include "../libmysql/mysql_trace.h"  /* MYSQL_TRACE() instrumentation */

#define STATE_DATA(M) \
  (NULL != (M) ? &(MYSQL_EXTENSION_PTR(M)->state_change) : NULL)

#define ADD_INFO(M, element, type)                                             \
{                                                                              \
  M= STATE_DATA(mysql);                                                       \
  M->info_list[type].head_node= list_add(M->info_list[type].head_node,         \
                                         element);                             \
}

#define native_password_plugin_name "mysql_native_password"

PSI_memory_key key_memory_mysql_options;
PSI_memory_key key_memory_MYSQL_DATA;
PSI_memory_key key_memory_MYSQL;
PSI_memory_key key_memory_MYSQL_RES;
PSI_memory_key key_memory_MYSQL_ROW;
PSI_memory_key key_memory_MYSQL_state_change_info;

#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
PSI_memory_key key_memory_create_shared_memory;
#endif /* _WIN32 && ! EMBEDDED_LIBRARY */

#ifdef HAVE_PSI_INTERFACE
/*
  This code is common to the client and server,
  and also used in the server when server A connects to server B,
  for example with replication.
  Therefore, the code is also instrumented.
*/

static PSI_memory_info all_client_memory[]=
{
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
  { &key_memory_create_shared_memory, "create_shared_memory", 0},
#endif /* _WIN32 && ! EMBEDDED_LIBRARY */

  { &key_memory_mysql_options, "mysql_options", 0},
  { &key_memory_MYSQL_DATA, "MYSQL_DATA", 0},
  { &key_memory_MYSQL, "MYSQL", 0},
  { &key_memory_MYSQL_RES, "MYSQL_RES", 0},
  { &key_memory_MYSQL_ROW, "MYSQL_ROW", 0},
  { &key_memory_MYSQL_state_change_info, "MYSQL_STATE_CHANGE_INFO", 0}
};

void init_client_psi_keys(void)
{
  const char *category= "client";
  int count;

  count= array_elements(all_client_memory);
  mysql_memory_register(category, all_client_memory, count);
}

#endif /* HAVE_PSI_INTERFACE */

const char      *default_ssl_cipher= "DHE-RSA-AES256-SHA";
uint		mysql_port=0;
char		*mysql_unix_port= 0;
const char	*unknown_sqlstate= "HY000";
const char	*not_error_sqlstate= "00000";
const char	*cant_connect_sqlstate= "08001";
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
char		 *shared_memory_base_name= 0;
const char 	*def_shared_memory_base_name= default_shared_memory_base_name;
#endif

void mysql_close_free_options(MYSQL *mysql);
void mysql_close_free(MYSQL *mysql);
static void mysql_prune_stmt_list(MYSQL *mysql);

CHARSET_INFO *default_client_charset_info = &my_charset_latin1;

/* Server error code and message */
unsigned int mysql_server_last_errno;
char mysql_server_last_error[MYSQL_ERRMSG_SIZE];
/* forward declaration */
static int read_one_row(MYSQL *mysql,uint fields,MYSQL_ROW row, ulong *lengths);
/**
  Convert the connect timeout option to a timeout value for VIO
  functions (vio_socket_connect() and vio_io_wait()).

  @param mysql  Connection handle (client side).

  @return The timeout value in milliseconds, or -1 if no timeout.
*/

static int get_vio_connect_timeout(MYSQL *mysql)
{
  int timeout_ms;
  uint timeout_sec;

  /*
    A timeout of 0 means no timeout. Also, the connect_timeout
    option value is in seconds, while VIO timeouts are measured
    in milliseconds. Hence, check for a possible overflow. In
    case of overflow, set to no timeout.
  */
  timeout_sec= mysql->options.connect_timeout;

  if (!timeout_sec || (timeout_sec > INT_MAX/1000))
    timeout_ms= -1;
  else
    timeout_ms= (int) (timeout_sec * 1000);

  return timeout_ms;
}


#ifdef _WIN32

/**
  Convert the connect timeout option to a timeout value for WIN32
  synchronization functions.

  @remark Specific for WIN32 connection methods shared memory and
          named pipe.

  @param mysql  Connection handle (client side).

  @return The timeout value in milliseconds, or INFINITE if no timeout.
*/

static DWORD get_win32_connect_timeout(MYSQL *mysql)
{
  DWORD timeout_ms;
  uint timeout_sec;

  /*
    A timeout of 0 means no timeout. Also, the connect_timeout
    option value is in seconds, while WIN32 timeouts are in
    milliseconds. Hence, check for a possible overflow. In case
    of overflow, set to no timeout.
  */
  timeout_sec= mysql->options.connect_timeout;

  if (!timeout_sec || (timeout_sec > INT_MAX/1000))
    timeout_ms= INFINITE;
  else
    timeout_ms= (DWORD) (timeout_sec * 1000);

  return timeout_ms;
}

#endif


/**
  Set the internal error message to mysql handler

  @param mysql    connection handle (client side)
  @param errcode  CR_ error code, passed to ER macro to get
                  error text
  @parma sqlstate SQL standard sqlstate
*/

void set_mysql_error(MYSQL *mysql, int errcode, const char *sqlstate)
{
  NET *net;
  DBUG_ENTER("set_mysql_error");
  DBUG_PRINT("enter", ("error :%d '%s'", errcode, ER(errcode)));
  DBUG_ASSERT(mysql != 0);

  if (mysql)
  {
    net= &mysql->net;
    net->last_errno= errcode;
    my_stpcpy(net->last_error, ER(errcode));
    my_stpcpy(net->sqlstate, sqlstate);
    MYSQL_TRACE(ERROR, mysql, ());
  }
  else
  {
    mysql_server_last_errno= errcode;
    my_stpcpy(mysql_server_last_error, ER(errcode));
  }
  DBUG_VOID_RETURN;
}

/**
  Is this NET instance initialized?
  @c my_net_init() and net_end()
 */

my_bool my_net_is_inited(NET *net)
{
  return net->buff != NULL;
}

/**
  Clear possible error state of struct NET

  @param net  clear the state of the argument
*/

void net_clear_error(NET *net)
{
  net->last_errno= 0;
  net->last_error[0]= '\0';
  my_stpcpy(net->sqlstate, not_error_sqlstate);
}

/**
  Set an error message on the client.

  @param mysql     connection handle
  @param errcode   CR_* errcode, for client errors
  @param sqlstate  SQL standard sql state, unknown_sqlstate for the
                   majority of client errors.
  @param format    error message template, in sprintf format
  @param ...       variable number of arguments
*/

void set_mysql_extended_error(MYSQL *mysql, int errcode,
                                     const char *sqlstate,
                                     const char *format, ...)
{
  NET *net;
  va_list args;
  DBUG_ENTER("set_mysql_extended_error");
  DBUG_PRINT("enter", ("error :%d '%s'", errcode, format));
  DBUG_ASSERT(mysql != 0);

  net= &mysql->net;
  net->last_errno= errcode;
  va_start(args, format);
  my_vsnprintf(net->last_error, sizeof(net->last_error)-1,
               format, args);
  va_end(args);
  my_stpcpy(net->sqlstate, sqlstate);

  MYSQL_TRACE(ERROR, mysql, ());

  DBUG_VOID_RETURN;
}



/*
  Create a named pipe connection
*/

#ifdef _WIN32

static HANDLE create_named_pipe(MYSQL *mysql, DWORD connect_timeout,
                                const char **arg_host,
                                const char **arg_unix_socket)
{
  HANDLE hPipe=INVALID_HANDLE_VALUE;
  char pipe_name[1024];
  DWORD dwMode;
  int i;
  my_bool testing_named_pipes=0;
  const char *host= *arg_host, *unix_socket= *arg_unix_socket;

  if ( ! unix_socket || (unix_socket)[0] == 0x00)
    unix_socket = mysql_unix_port;
  if (!host || !strcmp(host,LOCAL_HOST))
    host=LOCAL_HOST_NAMEDPIPE;

  
  pipe_name[sizeof(pipe_name)-1]= 0;		/* Safety if too long string */
  strxnmov(pipe_name, sizeof(pipe_name)-1, "\\\\", host, "\\pipe\\",
	   unix_socket, NullS);
  DBUG_PRINT("info",("Server name: '%s'.  Named Pipe: %s", host, unix_socket));

  for (i=0 ; i < 100 ; i++)			/* Don't retry forever */
  {
    if ((hPipe = CreateFile(pipe_name,
			    GENERIC_READ | GENERIC_WRITE,
			    0,
			    NULL,
			    OPEN_EXISTING,
			    FILE_FLAG_OVERLAPPED,
			    NULL )) != INVALID_HANDLE_VALUE)
      break;
    if (GetLastError() != ERROR_PIPE_BUSY)
    {
      set_mysql_extended_error(mysql, CR_NAMEDPIPEOPEN_ERROR,
                               unknown_sqlstate, ER(CR_NAMEDPIPEOPEN_ERROR),
                               host, unix_socket, (ulong) GetLastError());
      return INVALID_HANDLE_VALUE;
    }
    /* wait for for an other instance */
    if (!WaitNamedPipe(pipe_name, connect_timeout))
    {
      set_mysql_extended_error(mysql, CR_NAMEDPIPEWAIT_ERROR, unknown_sqlstate,
                               ER(CR_NAMEDPIPEWAIT_ERROR),
                               host, unix_socket, (ulong) GetLastError());
      return INVALID_HANDLE_VALUE;
    }
  }
  if (hPipe == INVALID_HANDLE_VALUE)
  {
    set_mysql_extended_error(mysql, CR_NAMEDPIPEOPEN_ERROR, unknown_sqlstate,
                             ER(CR_NAMEDPIPEOPEN_ERROR), host, unix_socket,
                             (ulong) GetLastError());
    return INVALID_HANDLE_VALUE;
  }
  dwMode = PIPE_READMODE_BYTE | PIPE_WAIT;
  if ( !SetNamedPipeHandleState(hPipe, &dwMode, NULL, NULL) )
  {
    CloseHandle( hPipe );
    set_mysql_extended_error(mysql, CR_NAMEDPIPESETSTATE_ERROR,
                             unknown_sqlstate, ER(CR_NAMEDPIPESETSTATE_ERROR),
                             host, unix_socket, (ulong) GetLastError());
    return INVALID_HANDLE_VALUE;
  }
  *arg_host=host ; *arg_unix_socket=unix_socket;	/* connect arg */
  return (hPipe);
}
#endif


/*
  Create new shared memory connection, return handler of connection

  @param mysql  Pointer of mysql structure
  @param net    Pointer of net structure
  @param connect_timeout  Timeout of connection (in milliseconds)

  @return HANDLE to the shared memory area.
*/

#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
static HANDLE create_shared_memory(MYSQL *mysql, NET *net,
                                   DWORD connect_timeout)
{
  ulong smem_buffer_length = shared_memory_buffer_length + 4;
  /*
    event_connect_request is event object for start connection actions
    event_connect_answer is event object for confirm, that server put data
    handle_connect_file_map is file-mapping object, use for create shared
    memory
    handle_connect_map is pointer on shared memory
    handle_map is pointer on shared memory for client
    event_server_wrote,
    event_server_read,
    event_client_wrote,
    event_client_read are events for transfer data between server and client
    handle_file_map is file-mapping object, use for create shared memory
  */
  HANDLE event_connect_request = NULL;
  HANDLE event_connect_answer = NULL;
  HANDLE handle_connect_file_map = NULL;
  char *handle_connect_map = NULL;

  char *handle_map = NULL;
  HANDLE event_server_wrote = NULL;
  HANDLE event_server_read = NULL;
  HANDLE event_client_wrote = NULL;
  HANDLE event_client_read = NULL;
  HANDLE event_conn_closed = NULL;
  HANDLE handle_file_map = NULL;
  ulong connect_number;
  char connect_number_char[22], *p;
  char *tmp= NULL;
  char *suffix_pos;
  DWORD error_allow = 0;
  DWORD error_code = 0;
  DWORD event_access_rights= SYNCHRONIZE | EVENT_MODIFY_STATE;
  char *shared_memory_base_name = mysql->options.shared_memory_base_name;
  static const char *name_prefixes[] = {"","Global\\"};
  const char *prefix;
  int i;

  /*
    If this is NULL, somebody freed the MYSQL* options.  mysql_close()
    is a good candidate.  We don't just silently (re)set it to
    def_shared_memory_base_name as that would create really confusing/buggy
    behavior if the user passed in a different name on the command-line or
    in a my.cnf.
  */
  DBUG_ASSERT(shared_memory_base_name != NULL);

  /*
     get enough space base-name + '_' + longest suffix we might ever send
   */
  if (!(tmp= (char *)my_malloc(key_memory_create_shared_memory,
                               strlen(shared_memory_base_name) + 32L, MYF(MY_FAE))))
    goto err;

  /*
    The name of event and file-mapping events create agree next rule:
    shared_memory_base_name+unique_part
    Where:
    shared_memory_base_name is unique value for each server
    unique_part is uniquel value for each object (events and file-mapping)
  */
  for (i = 0; i< array_elements(name_prefixes); i++)
  {
    prefix= name_prefixes[i];
    suffix_pos = strxmov(tmp, prefix , shared_memory_base_name, "_", NullS);
    my_stpcpy(suffix_pos, "CONNECT_REQUEST");
    event_connect_request= OpenEvent(event_access_rights, FALSE, tmp);
    if (event_connect_request)
    {
      break;
    }
  }
  if (!event_connect_request)
  {
    error_allow = CR_SHARED_MEMORY_CONNECT_REQUEST_ERROR;
    goto err;
  }
  my_stpcpy(suffix_pos, "CONNECT_ANSWER");
  if (!(event_connect_answer= OpenEvent(event_access_rights,FALSE,tmp)))
  {
    error_allow = CR_SHARED_MEMORY_CONNECT_ANSWER_ERROR;
    goto err;
  }
  my_stpcpy(suffix_pos, "CONNECT_DATA");
  if (!(handle_connect_file_map= OpenFileMapping(FILE_MAP_WRITE,FALSE,tmp)))
  {
    error_allow = CR_SHARED_MEMORY_CONNECT_FILE_MAP_ERROR;
    goto err;
  }
  if (!(handle_connect_map= MapViewOfFile(handle_connect_file_map,
					  FILE_MAP_WRITE,0,0,sizeof(DWORD))))
  {
    error_allow = CR_SHARED_MEMORY_CONNECT_MAP_ERROR;
    goto err;
  }

  /* Send to server request of connection */
  if (!SetEvent(event_connect_request))
  {
    error_allow = CR_SHARED_MEMORY_CONNECT_SET_ERROR;
    goto err;
  }

  /* Wait of answer from server */
  if (WaitForSingleObject(event_connect_answer, connect_timeout) !=
      WAIT_OBJECT_0)
  {
    error_allow = CR_SHARED_MEMORY_CONNECT_ABANDONED_ERROR;
    goto err;
  }

  /* Get number of connection */
  connect_number = uint4korr(handle_connect_map);/*WAX2*/
  p= int10_to_str(connect_number, connect_number_char, 10);

  /*
    The name of event and file-mapping events create agree next rule:
    shared_memory_base_name+unique_part+number_of_connection

    Where:
    shared_memory_base_name is uniquel value for each server
    unique_part is uniquel value for each object (events and file-mapping)
    number_of_connection is number of connection between server and client
  */
  suffix_pos = strxmov(tmp, prefix , shared_memory_base_name, "_", connect_number_char,
		       "_", NullS);
  my_stpcpy(suffix_pos, "DATA");
  if ((handle_file_map = OpenFileMapping(FILE_MAP_WRITE,FALSE,tmp)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_FILE_MAP_ERROR;
    goto err2;
  }
  if ((handle_map = MapViewOfFile(handle_file_map,FILE_MAP_WRITE,0,0,
				  smem_buffer_length)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_MAP_ERROR;
    goto err2;
  }

  my_stpcpy(suffix_pos, "SERVER_WROTE");
  if ((event_server_wrote = OpenEvent(event_access_rights,FALSE,tmp)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_EVENT_ERROR;
    goto err2;
  }

  my_stpcpy(suffix_pos, "SERVER_READ");
  if ((event_server_read = OpenEvent(event_access_rights,FALSE,tmp)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_EVENT_ERROR;
    goto err2;
  }

  my_stpcpy(suffix_pos, "CLIENT_WROTE");
  if ((event_client_wrote = OpenEvent(event_access_rights,FALSE,tmp)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_EVENT_ERROR;
    goto err2;
  }

  my_stpcpy(suffix_pos, "CLIENT_READ");
  if ((event_client_read = OpenEvent(event_access_rights,FALSE,tmp)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_EVENT_ERROR;
    goto err2;
  }

  my_stpcpy(suffix_pos, "CONNECTION_CLOSED");
  if ((event_conn_closed = OpenEvent(event_access_rights,FALSE,tmp)) == NULL)
  {
    error_allow = CR_SHARED_MEMORY_EVENT_ERROR;
    goto err2;
  }
  /*
    Set event that server should send data
  */
  SetEvent(event_server_read);

err2:
  if (error_allow == 0)
  {
    net->vio= vio_new_win32shared_memory(handle_file_map,handle_map,
                                         event_server_wrote,
                                         event_server_read,event_client_wrote,
                                         event_client_read,event_conn_closed);
  }
  else
  {
    error_code = GetLastError();
    if (event_server_read)
      CloseHandle(event_server_read);
    if (event_server_wrote)
      CloseHandle(event_server_wrote);
    if (event_client_read)
      CloseHandle(event_client_read);
    if (event_client_wrote)
      CloseHandle(event_client_wrote);
    if (event_conn_closed)
      CloseHandle(event_conn_closed);
    if (handle_map)
      UnmapViewOfFile(handle_map);
    if (handle_file_map)
      CloseHandle(handle_file_map);
  }
err:
  my_free(tmp);
  if (error_allow)
    error_code = GetLastError();
  if (event_connect_request)
    CloseHandle(event_connect_request);
  if (event_connect_answer)
    CloseHandle(event_connect_answer);
  if (handle_connect_map)
    UnmapViewOfFile(handle_connect_map);
  if (handle_connect_file_map)
    CloseHandle(handle_connect_file_map);
  if (error_allow)
  {
    if (error_allow == CR_SHARED_MEMORY_EVENT_ERROR)
      set_mysql_extended_error(mysql, error_allow, unknown_sqlstate,
                               ER(error_allow), suffix_pos, error_code);
    else
      set_mysql_extended_error(mysql, error_allow, unknown_sqlstate,
                               ER(error_allow), error_code);
    return(INVALID_HANDLE_VALUE);
  }
  return(handle_map);
}
#endif

/*
  Free all memory acquired to store state change information.
*/
void free_state_change_info(MYSQL_EXTENSION *ext)
{
  STATE_INFO *info;
  int i;

  if (ext)
    info= &ext->state_change;
  else
    return;

  for (i= SESSION_TRACK_SYSTEM_VARIABLES; i <= SESSION_TRACK_END; i++)
  {
    if (list_length(info->info_list[i].head_node) != 0)
    {
      /*
        Since nodes were multi-alloced, we don't need to free the data
        separately. But the str member in data needs to be freed.
      */
      LIST *tmp_list= info->info_list[i].head_node;
      while (tmp_list)
      {
	LEX_STRING *tmp= (LEX_STRING *)(tmp_list)->data;
	if (tmp->str)
	  my_free(tmp->str);
	tmp_list= tmp_list->next;
      }
      list_free(info->info_list[i].head_node, (uint) 0);
    }
  }
  memset(info, 0, sizeof(STATE_INFO));
}


/**
  Read Ok packet along with the server state change information.
*/
void read_ok_ex(MYSQL *mysql, ulong length)
{
  size_t total_len, len;
  uchar *pos, *saved_pos;
  char *db;

  struct charset_info_st *saved_cs;
  char charset_name[64];
  my_bool is_charset;

  STATE_INFO *info= NULL;
  enum enum_session_state_type type;
  LIST *element= NULL;
  LEX_STRING *data=NULL;

  pos= mysql->net.read_pos + 1;

  /* affected rows */
  mysql->affected_rows= net_field_length_ll(&pos);
  /* insert id */
  mysql->insert_id= net_field_length_ll(&pos);

  DBUG_PRINT("info",("affected_rows: %lu  insert_id: %lu",
                     (ulong) mysql->affected_rows,
                     (ulong) mysql->insert_id));

  /* server status */
  mysql->server_status= uint2korr(pos);
  pos += 2;

  if (protocol_41(mysql))
  {
    mysql->warning_count=uint2korr(pos);
    pos += 2;
  } else
    mysql->warning_count= 0;                    /* MySQL 4.0 protocol */

  DBUG_PRINT("info",("status: %u  warning_count: %u",
                     mysql->server_status, mysql->warning_count));
  if (mysql->server_capabilities & CLIENT_SESSION_TRACK)
  {
    free_state_change_info(mysql->extension);

    if (pos < mysql->net.read_pos + length)
    {
      /* get the info field */
      size_t length_msg_member= (size_t)net_field_length(&pos);
      mysql->info= (length_msg_member ? (char *)pos : NULL);
      pos += (length_msg_member);

      /* read session state changes info */
      if (mysql->server_status & SERVER_SESSION_STATE_CHANGED)
      {
        saved_pos= pos;
        total_len= (size_t)net_field_length(&pos);
        /* ensure that mysql->info is zero-terminated */
        if (mysql->info)
          *saved_pos= 0;

        while (total_len > 0)
        {
          saved_pos= pos;
          type= (enum enum_session_state_type) net_field_length(&pos);

          switch (type)
          {
          case SESSION_TRACK_SYSTEM_VARIABLES:
            /* Move past the total length of the changed entity. */
            (void) net_field_length(&pos);

            /* Name of the system variable. */
            len= (size_t) net_field_length(&pos);

            if (!my_multi_malloc(key_memory_MYSQL_state_change_info,
              MYF(0),
              &element, sizeof(LIST),
              &data, sizeof(LEX_STRING),
              NullS))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }

            if(!(data->str= (char *)my_malloc(PSI_NOT_INSTRUMENTED, len, MYF(MY_WME))))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }
            memcpy(data->str, (char *) pos, len);
            data->length= len;
            pos += len;

            element->data= data;
            ADD_INFO(info, element, SESSION_TRACK_SYSTEM_VARIABLES);

            /*
              Check if the changed variable was charset. In that case we need to
              update mysql->charset.
              */
            if (!strncmp(data->str, "character_set_client", data->length))
              is_charset= 1;
            else
              is_charset= 0;

            if (!my_multi_malloc(key_memory_MYSQL_state_change_info,
              MYF(0),
              &element, sizeof(LIST),
              &data, sizeof(LEX_STRING),
              NullS))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }

            /* Value of the system variable. */
            len= (size_t) net_field_length(&pos);
            if(!(data->str= (char *)my_malloc(PSI_NOT_INSTRUMENTED, len, MYF(MY_WME))))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }
            memcpy(data->str, (char *) pos, len);
            data->length= len;
            pos += len;

            element->data= data;
            ADD_INFO(info, element, SESSION_TRACK_SYSTEM_VARIABLES);

            if (is_charset == 1)
            {
              saved_cs= mysql->charset;

              memcpy(charset_name, data->str, data->length);
              charset_name[data->length]= 0;

              if (!(mysql->charset= get_charset_by_csname(charset_name,
                MY_CS_PRIMARY,
                MYF(MY_WME))))
              {
                /* Ideally, the control should never reach her. */
                DBUG_ASSERT(0);
                mysql->charset= saved_cs;
              }
            }
            break;
          case SESSION_TRACK_SCHEMA:

            if (!my_multi_malloc(key_memory_MYSQL_state_change_info,
              MYF(0),
              &element, sizeof(LIST),
              &data, sizeof(LEX_STRING),
              NullS))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }

            /* Move past the total length of the changed entity. */
            (void) net_field_length(&pos);

            len= (size_t) net_field_length(&pos);
            if(!(data->str= (char *)my_malloc(PSI_NOT_INSTRUMENTED, len, MYF(MY_WME))))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }
            memcpy(data->str, (char *) pos, len);
            data->length= len;
            pos += len;

            element->data= data;
            ADD_INFO(info, element, SESSION_TRACK_SCHEMA);

            if (!(db= (char *) my_malloc(key_memory_MYSQL_state_change_info,
              data->length + 1, MYF(MY_WME))))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }

            if (mysql->db)
              my_free(mysql->db);

            memcpy(db, data->str, data->length);
            db[data->length]= '\0';
            mysql->db= db;

            break;
          case SESSION_TRACK_STATE_CHANGE:
            if (!my_multi_malloc(key_memory_MYSQL_state_change_info,
              MYF(0),
              &element, sizeof(LIST),
              &data, sizeof(LEX_STRING),
              NullS))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }

            /* Get the length of the boolean tracker */
            len= (size_t) net_field_length(&pos);
            /* length for boolean tracker is always 1 */
            DBUG_ASSERT(len == 1);
            if(!(data->str= (char *)my_malloc(PSI_NOT_INSTRUMENTED, len, MYF(MY_WME))))
            {
              set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
              return;
            }
            memcpy(data->str, (char *) pos, len);
            data->length= len;
            pos += len;

            element->data= data;
            ADD_INFO(info, element, SESSION_TRACK_STATE_CHANGE);

            break;
          default:
            DBUG_ASSERT(type <= SESSION_TRACK_END);
            /*
              Unknown/unsupported type received, get the total length and move
              past it.
              */
            len= (size_t) net_field_length(&pos);
            pos += len;
            break;
          }
          total_len -= (pos - saved_pos);
        }
        if (info)
        {
          for (type= SESSION_TRACK_BEGIN; type < SESSION_TRACK_END; type++)
          {
            if (info->info_list[type].head_node)
            {
              info->info_list[type].current_node=
                info->info_list[type].head_node=
                  list_reverse(info->info_list[type].head_node);
            }
          }
        }
      }
    }
  }
  else if (pos < mysql->net.read_pos + length && net_field_length(&pos))
    mysql->info=(char*) pos;
  else
    mysql->info=NULL;
  return;
}


/**
  Read a packet from server. Give error message if socket was down
  or packet is an error message

  @param[IN]    mysql           connection handle
  @param[IN]    parse_ok        if set to TRUE then parse OK packet
                                if it is received
  @param[OUT]   is_data_packet
                                if set to TRUE then packet received is
                                a "data packet", that is not OK or ERR
                                packet or EOF in case of old servers

  @retval  The length of the packet that was read or packet_error in
           case of error. In case of error its description is stored
            in mysql handle.
*/

ulong
cli_safe_read_with_ok(MYSQL *mysql, my_bool parse_ok,
                      my_bool *is_data_packet)
{
  NET *net= &mysql->net;
  ulong len=0;

  MYSQL_TRACE(READ_PACKET, mysql, ());

  if (is_data_packet)
    *is_data_packet= FALSE;

  if (net->vio != 0)
    len=my_net_read(net);

  if (len == packet_error || len == 0)
  {
    DBUG_PRINT("error",("Wrong connection or packet. fd: %s  len: %lu",
			vio_description(net->vio),len));
#ifdef MYSQL_SERVER
    if (net->vio && (net->last_errno == ER_NET_READ_INTERRUPTED))
      return (packet_error);
#endif /*MYSQL_SERVER*/
    end_server(mysql);
    set_mysql_error(mysql, net->last_errno == ER_NET_PACKET_TOO_LARGE ?
                    CR_NET_PACKET_TOO_LARGE: CR_SERVER_LOST, unknown_sqlstate);
    return (packet_error);
  }

  MYSQL_TRACE(PACKET_RECEIVED, mysql, (len, net->read_pos));
  
  if (net->read_pos[0] == 255)
  {
    /*
      After server reprts an error, usually it is ready to accept new commands and
      we set stage to READY_FOR_COMMAND. This can be modified by the caller of 
      cli_safe_read().
    */
    MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);

    if (len > 3)
    {
      uchar *pos= net->read_pos+1;
      net->last_errno=uint2korr(pos);
      pos+=2;
      len-=2;
      if (protocol_41(mysql) && pos[0] == '#')
      {
	strmake(net->sqlstate, (char*)pos+1, SQLSTATE_LENGTH);
	pos+= SQLSTATE_LENGTH+1;
      }
      else
      {
        /*
          The SQL state hasn't been received -- it should be reset to HY000
          (unknown error sql state).
        */

        my_stpcpy(net->sqlstate, unknown_sqlstate);
      }

      (void) strmake(net->last_error,(char*) pos,
		     MY_MIN((uint) len,(uint) sizeof(net->last_error)-1));
    }
    else
      set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
    /*
      Cover a protocol design error: error packet does not
      contain the server status. Therefore, the client has no way
      to find out whether there are more result sets of
      a multiple-result-set statement pending. Luckily, in 5.0 an
      error always aborts execution of a statement, wherever it is
      a multi-statement or a stored procedure, so it should be
      safe to unconditionally turn off the flag here.
    */
    mysql->server_status&= ~SERVER_MORE_RESULTS_EXISTS;

    DBUG_PRINT("error",("Got error: %d/%s (%s)",
                        net->last_errno,
                        net->sqlstate,
                        net->last_error));
    return(packet_error);
  }
  else
  {
    /* if it is OK packet irrespective of new/old server */
    if (net->read_pos[0] == 0)
    {
      if (parse_ok)
      {
        read_ok_ex(mysql, len);
        return len;
      }
    }
    /*
      Now we have a data packet, unless it is OK packet starting with
      0xFE - we detect that case below.
    */
    if (is_data_packet)
      *is_data_packet= TRUE;
    /*
       For a packet starting with 0xFE detect if it is OK packet or a
       huge data packet. Note that old servers do not send OK packets
       starting with 0xFE.
    */
    if ((mysql->server_capabilities & CLIENT_DEPRECATE_EOF) &&
        (net->read_pos[0] == 254))
    {
      /* detect huge data packet */
      if (len > MAX_PACKET_LENGTH)
        return len;
      /* otherwise we have OK packet starting with 0xFE */
      if (is_data_packet)
        *is_data_packet= FALSE;
      /* parse it if requested */
      if (parse_ok)
        read_ok_ex(mysql, len);
      return len;
    }
    /* for old client detect EOF packet */
    if (!(mysql->server_capabilities & CLIENT_DEPRECATE_EOF) &&
        (net->read_pos[0] == 254) && (len < 8))
    {
      if (is_data_packet)
        *is_data_packet= FALSE;
    }
  }
  return len;
}


/**
  Read a packet from server. Give error message if connection was broken or
  ERR packet was received. Detect if the packet received was an OK, ERR or
  something else (a "data packet").

  @param[IN]  mysql           connection handle
  @param[OUT] is_data_packet
                              if set to TRUE then the packet received
                              was a "data packet".

  @retval The length of the packet that was read or packet_error in case of
          error. In case of error its description is stored in mysql handle.
*/
ulong cli_safe_read(MYSQL *mysql, my_bool *is_data_packet)
{
  return cli_safe_read_with_ok(mysql, 0, is_data_packet);
}


void free_rows(MYSQL_DATA *cur)
{
  if (cur)
  {
    free_root(&cur->alloc,MYF(0));
    my_free(cur);
  }
}

my_bool
cli_advanced_command(MYSQL *mysql, enum enum_server_command command,
		     const uchar *header, size_t header_length,
		     const uchar *arg, size_t arg_length, my_bool skip_check,
                     MYSQL_STMT *stmt)
{
  NET *net= &mysql->net;
  my_bool result= 1;
  my_bool stmt_skip= stmt ? stmt->state != MYSQL_STMT_INIT_DONE : FALSE;
  DBUG_ENTER("cli_advanced_command");

  if (mysql->net.vio == 0)
  {						/* Do reconnect if possible */
    if (mysql_reconnect(mysql) || stmt_skip)
      DBUG_RETURN(1);
  }
  if (mysql->status != MYSQL_STATUS_READY ||
      mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
  {
    DBUG_PRINT("error",("state: %d", mysql->status));
    set_mysql_error(mysql, CR_COMMANDS_OUT_OF_SYNC, unknown_sqlstate);
    DBUG_RETURN(1);
  }

  net_clear_error(net);
  mysql->info=0;
  mysql->affected_rows= ~(my_ulonglong) 0;
  /*
    Do not check the socket/protocol buffer on COM_QUIT as the
    result of a previous command might not have been read. This
    can happen if a client sends a query but does not reap the
    result before attempting to close the connection.
  */
  net_clear(&mysql->net, (command != COM_QUIT));

  MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
  MYSQL_TRACE(SEND_COMMAND, mysql, (command, header_length, arg_length, header, arg));

#if !defined(EMBEDDED_LIBRARY)
  /*
    If auto-reconnect mode is enabled check if connection is still alive before
    sending new command. Otherwise, send() might not notice that connection was
    closed by the server (for example, due to KILL statement), and the fact that
    connection is gone will be noticed only on attempt to read command's result,
    when it is too late to reconnect. Note that such scenario can still occur if
    connection gets killed after this check but before command is sent to
    server. But this should be rare.
  */
  if ((command != COM_QUIT) && mysql->reconnect && !vio_is_connected(net->vio))
    net->error= 2;
#endif

  if (net_write_command(net,(uchar) command, header, header_length,
			arg, arg_length))
  {
    DBUG_PRINT("error",("Can't send command to server. Error: %d",
			socket_errno));
    if (net->last_errno == ER_NET_PACKET_TOO_LARGE)
    {
      set_mysql_error(mysql, CR_NET_PACKET_TOO_LARGE, unknown_sqlstate);
      goto end;
    }
    end_server(mysql);
    if (mysql_reconnect(mysql) || stmt_skip)
      goto end;
    
    MYSQL_TRACE(SEND_COMMAND, mysql, (command, header_length, arg_length, header, arg));
    if (net_write_command(net,(uchar) command, header, header_length,
			  arg, arg_length))
    {
      set_mysql_error(mysql, CR_SERVER_GONE_ERROR, unknown_sqlstate);
      goto end;
    }
  }

  MYSQL_TRACE(PACKET_SENT, mysql, (header_length + arg_length)); 

#if defined(CLIENT_PROTOCOL_TRACING)
  switch (command)
  {
  case COM_STMT_PREPARE:
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_PS_DESCRIPTION);
    break;

  case COM_STMT_FETCH:
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_ROW);
    break;

  /* 
    No server reply is expected after these commands so we reamin ready
    for the next command.
 */
  case COM_STMT_SEND_LONG_DATA: 
  case COM_STMT_CLOSE:
  case COM_REGISTER_SLAVE:
  case COM_QUIT:
    break;

  /*
    These replication commands are not supported and we bail out
    by pretending that connection has been closed.
  */
  case COM_BINLOG_DUMP:
  case COM_BINLOG_DUMP_GTID:
  case COM_TABLE_DUMP:
    MYSQL_TRACE(DISCONNECTED, mysql, ());
    break;

  /*
    After COM_CHANGE_USER a regular authentication exchange
    is performed.
  */
  case COM_CHANGE_USER:
    MYSQL_TRACE_STAGE(mysql, AUTHENTICATE);
    break;

  /*
    Server replies to COM_STATISTICS with a single packet 
    containing a string with statistics information.
  */
  case COM_STATISTICS:
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_PACKET);
    break;

  /*
    For all other commands we expect server to send regular reply which
    is either OK, ERR or a result-set header.
  */
  default: MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT); break;
  }
#endif

  result=0;
  if (!skip_check)
  {
    result= ((mysql->packet_length= cli_safe_read_with_ok(mysql, 1, NULL)) ==
             packet_error ? 1 : 0);

#if defined(CLIENT_PROTOCOL_TRACING)
    /*
      Return to READY_FOR_COMMAND protocol stage in case server reports error 
      or sends OK packet.
    */
    if (!result || mysql->net.read_pos[0] == 0x00)
      MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
#endif
  }

end:
  DBUG_PRINT("exit",("result: %d", result));
  DBUG_RETURN(result);
}

void free_old_query(MYSQL *mysql)
{
  DBUG_ENTER("free_old_query");
  if (mysql->fields)
    free_root(&mysql->field_alloc,MYF(0));
  init_alloc_root(PSI_NOT_INSTRUMENTED,
                  &mysql->field_alloc, 8192, 0); /* Assume rowlength < 8192 */
  mysql->fields= 0;
  mysql->field_count= 0;			/* For API */
  mysql->warning_count= 0;
  mysql->info= 0;
  DBUG_VOID_RETURN;
}


/**
  Finish reading of a partial result set from the server.
  Get the EOF packet, and update mysql->status
  and mysql->warning_count.

  @return  TRUE if a communication or protocol error, an error
           is set in this case, FALSE otherwise.
*/

my_bool flush_one_result(MYSQL *mysql)
{
  ulong packet_length;
  my_bool is_data_packet;

  DBUG_ASSERT(mysql->status != MYSQL_STATUS_READY);

  do
  {
    packet_length= cli_safe_read(mysql, &is_data_packet);
    /*
      There is an error reading from the connection,
      or (sic!) there were no error and no
      data in the stream, i.e. no more data from the server.
      Since we know our position in the stream (somewhere in
      the middle of a result set), this latter case is an error too
      -- each result set must end with a EOF packet.
      cli_safe_read() has set an error for us, just return.
    */
    if (packet_length == packet_error)
      return TRUE;
  }
  while (mysql->net.read_pos[0] == 0 || is_data_packet);

  /* Analyse final OK packet (EOF packet if it is old client) */

  if (protocol_41(mysql))
  {
    uchar *pos= mysql->net.read_pos + 1;
    if (mysql->server_capabilities & CLIENT_DEPRECATE_EOF &&
        !is_data_packet)
      read_ok_ex(mysql, packet_length);
    else
    {
      mysql->warning_count= uint2korr(pos);
      pos+=2;
      mysql->server_status=uint2korr(pos);
    }
    pos+=2;
  }
#if defined(CLIENT_PROTOCOL_TRACING)
  if (mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT);
  else
    MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
#endif
  return FALSE;
}


/**
  Read a packet from network. If it's an OK packet, flush it.

  @return  TRUE if error, FALSE otherwise. In case of 
           success, is_ok_packet is set to TRUE or FALSE,
           based on what we got from network.
*/

my_bool opt_flush_ok_packet(MYSQL *mysql, my_bool *is_ok_packet)
{
  my_bool is_data_packet;
  ulong packet_length= cli_safe_read(mysql, &is_data_packet);

  if (packet_length == packet_error)
    return TRUE;

  /* cli_safe_read always reads a non-empty packet. */
  DBUG_ASSERT(packet_length);

  *is_ok_packet= ((mysql->net.read_pos[0] == 0) ||
                  ((mysql->server_capabilities & CLIENT_DEPRECATE_EOF) &&
                   mysql->net.read_pos[0] == 254 &&
                   packet_length < MAX_PACKET_LENGTH));
  if (*is_ok_packet)
  {
    read_ok_ex(mysql, packet_length);
#if defined(CLIENT_PROTOCOL_TRACING)
    if (mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
      MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT);
    else
      MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
#endif
  }

  return FALSE;
}


/*
  Flush result set sent from server
*/

static void cli_flush_use_result(MYSQL *mysql, my_bool flush_all_results)
{
  /* Clear the current execution status */
  DBUG_ENTER("cli_flush_use_result");
  DBUG_PRINT("warning",("Not all packets read, clearing them"));

  if (flush_one_result(mysql))
    DBUG_VOID_RETURN;                           /* An error occurred */

  if (! flush_all_results)
    DBUG_VOID_RETURN;

  while (mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
  {
    my_bool is_ok_packet;
    if (opt_flush_ok_packet(mysql, &is_ok_packet))
      DBUG_VOID_RETURN;                         /* An error occurred. */
    if (is_ok_packet)
    {
      /*
        Indeed what we got from network was an OK packet, and we
        know that OK is the last one in a multi-result-set, so
        just return.
      */
      DBUG_VOID_RETURN;
    }

    /*
      It's a result set, not an OK packet. A result set contains
      of two result set subsequences: field metadata, terminated
      with EOF packet, and result set data, again terminated with
      EOF packet. Read and flush them.
    */
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_FIELD_DEF);
    if (!(mysql->server_capabilities & CLIENT_DEPRECATE_EOF))
    {
      if (flush_one_result(mysql))
        DBUG_VOID_RETURN;                         /* An error occurred. */
    }
    else
    {
      if ((mysql->fields= cli_read_metadata(mysql,
                       mysql->net.read_pos[0], protocol_41(mysql) ? 7:5)))
        free_root(&mysql->field_alloc,MYF(0));
      else
        DBUG_VOID_RETURN;
    }
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_ROW);
    if (flush_one_result(mysql))
      DBUG_VOID_RETURN;
  }
  DBUG_VOID_RETURN;
}


#ifdef _WIN32
static my_bool is_NT(void)
{
  char *os=getenv("OS");
  return (os && !strcmp(os, "Windows_NT")) ? 1 : 0;
}
#endif


#ifdef CHECK_LICENSE
/**
  Check server side variable 'license'.

  If the variable does not exist or does not contain 'Commercial',
  we're talking to non-commercial server from commercial client.

  @retval  0   success
  @retval  !0  network error or the server is not commercial.
               Error code is saved in mysql->net.last_errno.
*/

static int check_license(MYSQL *mysql)
{
  MYSQL_ROW row;
  MYSQL_RES *res;
  NET *net= &mysql->net;
  static const char query[]= "SELECT @@license";
  static const char required_license[]= STRINGIFY_ARG(LICENSE);

  if (mysql_real_query(mysql, query, (ulong)(sizeof(query)-1)))
  {
    if (net->last_errno == ER_UNKNOWN_SYSTEM_VARIABLE)
    {
      set_mysql_extended_error(mysql, CR_WRONG_LICENSE, unknown_sqlstate,
                               ER(CR_WRONG_LICENSE), required_license);
    }
    return 1;
  }
  if (!(res= mysql_use_result(mysql)))
    return 1;
  row= mysql_fetch_row(res);
  /* 
    If no rows in result set, or column value is NULL (none of these
    two is ever true for server variables now), or column value
    mismatch, set wrong license error.
  */
  if (!net->last_errno &&
      (!row || !row[0] ||
       strncmp(row[0], required_license, sizeof(required_license))))
  {
    set_mysql_extended_error(mysql, CR_WRONG_LICENSE, unknown_sqlstate,
                             ER(CR_WRONG_LICENSE), required_license);
  }
  mysql_free_result(res);
  return net->last_errno;
}
#endif /* CHECK_LICENSE */


/**************************************************************************
  Shut down connection
**************************************************************************/

void end_server(MYSQL *mysql)
{
  int save_errno= errno;
  DBUG_ENTER("end_server");
  if (mysql->net.vio != 0)
  {
    DBUG_PRINT("info",("Net: %s", vio_description(mysql->net.vio)));
#ifdef MYSQL_SERVER
    slave_io_thread_detach_vio();
#endif
    vio_delete(mysql->net.vio);
    mysql->net.vio= 0;          /* Marker */
    mysql_prune_stmt_list(mysql);
  }
  net_end(&mysql->net);
  free_old_query(mysql);
  errno= save_errno;
  MYSQL_TRACE(DISCONNECTED, mysql, ());
  DBUG_VOID_RETURN;
}


void STDCALL
mysql_free_result(MYSQL_RES *result)
{
  DBUG_ENTER("mysql_free_result");
  DBUG_PRINT("enter",("mysql_res: 0x%lx", (long) result));
  if (result)
  {
    MYSQL *mysql= result->handle;
    if (mysql)
    {
      if (mysql->unbuffered_fetch_owner == &result->unbuffered_fetch_cancelled)
        mysql->unbuffered_fetch_owner= 0;
      if (mysql->status == MYSQL_STATUS_USE_RESULT)
      {
        (*mysql->methods->flush_use_result)(mysql, FALSE);
        mysql->status=MYSQL_STATUS_READY;
        if (mysql->unbuffered_fetch_owner)
          *mysql->unbuffered_fetch_owner= TRUE;
      }
    }
    free_rows(result->data);
    if (result->fields)
      free_root(&result->field_alloc,MYF(0));
    my_free(result->row);
    my_free(result);
  }
  DBUG_VOID_RETURN;
}

/****************************************************************************
  Get options from my.cnf
****************************************************************************/

static const char *default_options[]=
{
  "port","socket","compress","password","pipe", "timeout", "user",
  "init-command", "host", "database", "debug", "return-found-rows",
  "ssl-key" ,"ssl-cert" ,"ssl-ca" ,"ssl-capath",
  "character-sets-dir", "default-character-set", "interactive-timeout",
  "connect-timeout", "local-infile", "disable-local-infile",
  "ssl-cipher", "max-allowed-packet", "protocol", "shared-memory-base-name",
  "multi-results", "multi-statements", "multi-queries", "secure-auth",
  "report-data-truncation", "plugin-dir", "default-auth",
  "bind-address", "ssl-crl", "ssl-crlpath", "enable-cleartext-plugin",
  NullS
};
enum option_id {
  OPT_port=1, OPT_socket, OPT_compress, OPT_password, OPT_pipe, OPT_timeout, OPT_user, 
  OPT_init_command, OPT_host, OPT_database, OPT_debug, OPT_return_found_rows, 
  OPT_ssl_key, OPT_ssl_cert, OPT_ssl_ca, OPT_ssl_capath, 
  OPT_character_sets_dir, OPT_default_character_set, OPT_interactive_timeout, 
  OPT_connect_timeout, OPT_local_infile, OPT_disable_local_infile, 
  OPT_ssl_cipher, OPT_max_allowed_packet, OPT_protocol, OPT_shared_memory_base_name, 
  OPT_multi_results, OPT_multi_statements, OPT_multi_queries, OPT_secure_auth, 
  OPT_report_data_truncation, OPT_plugin_dir, OPT_default_auth,
  OPT_bind_address, OPT_ssl_crl, OPT_ssl_crlpath, OPT_enable_cleartext_plugin,
  OPT_keep_this_one_last
};

static TYPELIB option_types={array_elements(default_options)-1,
			     "options",default_options, NULL};

const char *sql_protocol_names_lib[] =
{ "TCP", "SOCKET", "PIPE", "MEMORY", NullS };
TYPELIB sql_protocol_typelib = {array_elements(sql_protocol_names_lib)-1,"",
				sql_protocol_names_lib, NULL};

static int add_init_command(struct st_mysql_options *options, const char *cmd)
{
  char *tmp;

  if (!options->init_commands)
  {
    options->init_commands= (DYNAMIC_ARRAY*)my_malloc(key_memory_mysql_options,
                                                      sizeof(DYNAMIC_ARRAY),
						      MYF(MY_WME));
    init_dynamic_array(options->init_commands,sizeof(char*),0,5);
  }

  if (!(tmp= my_strdup(key_memory_mysql_options,
                       cmd,MYF(MY_WME))) ||
      insert_dynamic(options->init_commands, &tmp))
  {
    my_free(tmp);
    return 1;
  }

  return 0;
}

#define ALLOCATE_EXTENSIONS(OPTS)                                \
      (OPTS)->extension= (struct st_mysql_options_extention *)   \
        my_malloc(key_memory_mysql_options,                      \
                  sizeof(struct st_mysql_options_extention),     \
                  MYF(MY_WME | MY_ZEROFILL))                     \

#define ENSURE_EXTENSIONS_PRESENT(OPTS)                          \
    do {                                                         \
      if (!(OPTS)->extension)                                    \
        ALLOCATE_EXTENSIONS(OPTS);                               \
    } while (0)


#define EXTENSION_SET_STRING(OPTS, X, STR)                       \
    do {                                                         \
      if ((OPTS)->extension)                                     \
        my_free((OPTS)->extension->X);                           \
      else                                                       \
        ALLOCATE_EXTENSIONS(OPTS);                               \
      (OPTS)->extension->X= ((STR) != NULL) ?                    \
        my_strdup(key_memory_mysql_options,                      \
                  (STR), MYF(MY_WME)) : NULL;                    \
    } while (0)

#define SET_OPTION(opt_var,arg) \
  do { \
    if (mysql->options.opt_var) \
      my_free(mysql->options.opt_var); \
    mysql->options.opt_var = arg ? my_strdup(key_memory_mysql_options, arg, MYF(MY_WME)) : NULL; \
  } while (0)


#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)
#define SET_SSL_OPTION(opt_var,arg) \
  do { \
    SET_OPTION(opt_var, arg); \
    if (mysql->options.opt_var) \
      mysql->options.use_ssl = TRUE; \
  } while (0)

#define EXTENSION_SET_SSL_STRING(OPTS, X, STR) \
  do { \
    EXTENSION_SET_STRING(OPTS, X, STR); \
    if ((OPTS)->extension->X) \
      (OPTS)->use_ssl = TRUE; \
  } while (0)
#else
#define SET_SSL_OPTION(opt_var,arg) \
    do { \
      ; \
    } while(0)
#define EXTENSION_SET_SSL_STRING(OPTS, X, STR) \
    do { \
      ; \
    } while(0)
#endif

void mysql_read_default_options(struct st_mysql_options *options,
				const char *filename,const char *group)
{
  int argc;
  char *argv_buff[1],**argv;
  const char *groups[3];
  DBUG_ENTER("mysql_read_default_options");
  DBUG_PRINT("enter",("file: %s  group: %s",filename,group ? group :"NULL"));

  compile_time_assert(OPT_keep_this_one_last ==
                      array_elements(default_options));

  argc=1; argv=argv_buff; argv_buff[0]= (char*) "client";
  groups[0]= (char*) "client"; groups[1]= (char*) group; groups[2]=0;

  my_load_defaults(filename, groups, &argc, &argv, NULL);
  if (argc != 1)				/* If some default option */
  {
    char **option=argv;
    while (*++option)
    {
      if (my_getopt_is_args_separator(option[0]))          /* skip arguments separator */
        continue;
      /* DBUG_PRINT("info",("option: %s",option[0])); */
      if (option[0][0] == '-' && option[0][1] == '-')
      {
	char *end=strcend(*option,'=');
	char *opt_arg=0;
	if (*end)
	{
	  opt_arg=end+1;
	  *end=0;				/* Remove '=' */
	}
	/* Change all '_' in variable name to '-' */
	for (end= *option ; *(end= strcend(end,'_')) ; )
	  *end= '-';
	switch (find_type(*option + 2, &option_types, FIND_TYPE_BASIC)) {
	case OPT_port:
	  if (opt_arg)
	    options->port=atoi(opt_arg);
	  break;
	case OPT_socket:
	  if (opt_arg)
	  {
	    my_free(options->unix_socket);
	    options->unix_socket=my_strdup(key_memory_mysql_options,
                                           opt_arg,MYF(MY_WME));
	  }
	  break;
	case OPT_compress:
	  options->compress=1;
	  options->client_flag|= CLIENT_COMPRESS;
	  break;
        case OPT_password:
	  if (opt_arg)
	  {
	    my_free(options->password);
	    options->password=my_strdup(key_memory_mysql_options,
                                        opt_arg,MYF(MY_WME));
	  }
	  break;
        case OPT_pipe:
          options->protocol = MYSQL_PROTOCOL_PIPE;
	case OPT_connect_timeout:
	case OPT_timeout:
	  if (opt_arg)
	    options->connect_timeout=atoi(opt_arg);
	  break;
	case OPT_user:
	  if (opt_arg)
	  {
	    my_free(options->user);
	    options->user=my_strdup(key_memory_mysql_options,
                                    opt_arg,MYF(MY_WME));
	  }
	  break;
	case OPT_init_command:
	  add_init_command(options,opt_arg);
	  break;
	case OPT_host:
	  if (opt_arg)
	  {
	    my_free(options->host);
	    options->host=my_strdup(key_memory_mysql_options,
                                    opt_arg,MYF(MY_WME));
	  }
	  break;
	case OPT_database:
	  if (opt_arg)
	  {
	    my_free(options->db);
	    options->db=my_strdup(key_memory_mysql_options,
                                  opt_arg,MYF(MY_WME));
	  }
	  break;
	case OPT_debug:
#ifdef MYSQL_CLIENT
	  mysql_debug(opt_arg ? opt_arg : "d:t:o,/tmp/client.trace");
	  break;
#endif
	case OPT_return_found_rows:
	  options->client_flag|=CLIENT_FOUND_ROWS;
	  break;
#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)
	case OPT_ssl_key:
	  my_free(options->ssl_key);
          options->ssl_key = my_strdup(key_memory_mysql_options,
                                       opt_arg, MYF(MY_WME));
          break;
	case OPT_ssl_cert:
	  my_free(options->ssl_cert);
          options->ssl_cert = my_strdup(key_memory_mysql_options,
                                        opt_arg, MYF(MY_WME));
          break;
	case OPT_ssl_ca:
	  my_free(options->ssl_ca);
          options->ssl_ca = my_strdup(key_memory_mysql_options,
                                      opt_arg, MYF(MY_WME));
          break;
	case OPT_ssl_capath:
	  my_free(options->ssl_capath);
          options->ssl_capath = my_strdup(key_memory_mysql_options,
                                          opt_arg, MYF(MY_WME));
          break;
        case OPT_ssl_cipher:
          my_free(options->ssl_cipher);
          options->ssl_cipher= my_strdup(key_memory_mysql_options,
                                         opt_arg, MYF(MY_WME));
          break;
	case OPT_ssl_crl:
          EXTENSION_SET_SSL_STRING(options, ssl_crl, opt_arg);
          break;
	case OPT_ssl_crlpath:
          EXTENSION_SET_SSL_STRING(options, ssl_crlpath, opt_arg);
          break;
#else
	case OPT_ssl_key:
	case OPT_ssl_cert:
	case OPT_ssl_ca:
	case OPT_ssl_capath:
        case OPT_ssl_cipher:
        case OPT_ssl_crl:
        case OPT_ssl_crlpath:
	  break;
#endif /* HAVE_OPENSSL && !EMBEDDED_LIBRARY */
	case OPT_character_sets_dir:
	  my_free(options->charset_dir);
          options->charset_dir = my_strdup(key_memory_mysql_options,
                                           opt_arg, MYF(MY_WME));
	  break;
	case OPT_default_character_set:
	  my_free(options->charset_name);
          options->charset_name = my_strdup(key_memory_mysql_options,
                                            opt_arg, MYF(MY_WME));
	  break;
	case OPT_interactive_timeout:
	  options->client_flag|= CLIENT_INTERACTIVE;
	  break;
	case OPT_local_infile:
	  if (!opt_arg || atoi(opt_arg) != 0)
	    options->client_flag|= CLIENT_LOCAL_FILES;
	  else
	    options->client_flag&= ~CLIENT_LOCAL_FILES;
	  break;
	case OPT_disable_local_infile:
	  options->client_flag&= ~CLIENT_LOCAL_FILES;
          break;
	case OPT_max_allowed_packet:
          if (opt_arg)
	    options->max_allowed_packet= atoi(opt_arg);
	  break;
        case OPT_protocol:
          if ((options->protocol= find_type(opt_arg, &sql_protocol_typelib,
                                            FIND_TYPE_BASIC)) <= 0)
          {
            my_message_local(ERROR_LEVEL,
                             "Unknown option to protocol: %s", opt_arg);
            exit(1);
          }
          break;
        case OPT_shared_memory_base_name:
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
          if (options->shared_memory_base_name != def_shared_memory_base_name)
            my_free(options->shared_memory_base_name);
          options->shared_memory_base_name=my_strdup(key_memory_mysql_options,
                                                     opt_arg,MYF(MY_WME));
#endif
          break;
	case OPT_multi_results:
	  options->client_flag|= CLIENT_MULTI_RESULTS;
	  break;
	case OPT_multi_statements:
	case OPT_multi_queries:
	  options->client_flag|= CLIENT_MULTI_STATEMENTS | CLIENT_MULTI_RESULTS;
	  break;
        case OPT_secure_auth:
          /* this is a no-op */
          break;
        case OPT_report_data_truncation:
          options->report_data_truncation= opt_arg ? MY_TEST(atoi(opt_arg)) : 1;
          break;
        case OPT_plugin_dir:
          {
            char buff[FN_REFLEN], buff2[FN_REFLEN];
            if (strlen(opt_arg) >= FN_REFLEN)
              opt_arg[FN_REFLEN]= '\0';
            if (my_realpath(buff, opt_arg, 0))
            {
              DBUG_PRINT("warning",("failed to normalize the plugin path: %s",
                                    opt_arg));
              break;
            }
            convert_dirname(buff2, buff, NULL);
            EXTENSION_SET_STRING(options, plugin_dir, buff2);
          }
          break;
        case OPT_default_auth:
          EXTENSION_SET_STRING(options, default_auth, opt_arg);
          break;
	case OPT_bind_address:
          my_free(options->ci.bind_address);
          options->ci.bind_address= my_strdup(key_memory_mysql_options,
                                              opt_arg, MYF(MY_WME));
          break;
        case OPT_enable_cleartext_plugin:
          ENSURE_EXTENSIONS_PRESENT(options);
          options->extension->enable_cleartext_plugin= 
            (!opt_arg || atoi(opt_arg) != 0) ? TRUE : FALSE;
          break;

	default:
	  DBUG_PRINT("warning",("unknown option: %s",option[0]));
	}
      }
    }
  }
  free_defaults(argv);
  DBUG_VOID_RETURN;
}


/**************************************************************************
  Get column lengths of the current row
  If one uses mysql_use_result, res->lengths contains the length information,
  else the lengths are calculated from the offset between pointers.
**************************************************************************/

static void cli_fetch_lengths(ulong *to, MYSQL_ROW column,
			      unsigned int field_count)
{ 
  ulong *prev_length;
  char *start=0;
  MYSQL_ROW end;

  prev_length=0;				/* Keep gcc happy */
  for (end=column + field_count + 1 ; column != end ; column++, to++)
  {
    if (!*column)
    {
      *to= 0;					/* Null */
      continue;
    }
    if (start)					/* Found end of prev string */
      *prev_length= (ulong) (*column-start-1);
    start= *column;
    prev_length= to;
  }
}

/**
  Read field metadata from field descriptor and store it in MYSQL_FIELD structure.
  String values in MYSQL_FIELD are allocated in a given allocator root.

  @param mysql          connection handle
  @param alloc          memory allocator root
  @param default_value  flag telling if default values should be read from
                        descriptor
  @param server_capabilities  protocol capability flags which determine format of
                              the descriptor
  @param row            field descriptor
  @param field          address of MYSQL_FIELD structure to store metadata in.

  @returns 0 on success.
*/

int
unpack_field(MYSQL *mysql, MEM_ROOT *alloc, my_bool default_value,
             uint server_capabilities, MYSQL_ROWS *row, MYSQL_FIELD *field)
{
  ulong lengths[9];                      /* Max length of each field */
  DBUG_ENTER("unpack_field");

  if (!field)
  {
    set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
    DBUG_RETURN(1);
  }

  memset(field, 0, sizeof(MYSQL_FIELD));

  if (server_capabilities & CLIENT_PROTOCOL_41)
  {
    uchar *pos;
    /* fields count may be wrong */
    cli_fetch_lengths(&lengths[0], row->data, default_value ? 8 : 7);
    field->catalog=   strmake_root(alloc,(char*) row->data[0], lengths[0]);
    field->db=        strmake_root(alloc,(char*) row->data[1], lengths[1]);
    field->table=     strmake_root(alloc,(char*) row->data[2], lengths[2]);
    field->org_table= strmake_root(alloc,(char*) row->data[3], lengths[3]);
    field->name=      strmake_root(alloc,(char*) row->data[4], lengths[4]);
    field->org_name=  strmake_root(alloc,(char*) row->data[5], lengths[5]);

    field->catalog_length=	lengths[0];
    field->db_length=		lengths[1];
    field->table_length=	lengths[2];
    field->org_table_length=	lengths[3];
    field->name_length=	lengths[4];
    field->org_name_length=	lengths[5];

    /* Unpack fixed length parts */
    if (lengths[6] != 12)
    {
      /* malformed packet. signal an error. */
      set_mysql_error(mysql, CR_MALFORMED_PACKET, unknown_sqlstate);
      DBUG_RETURN(1);
    }

    pos= (uchar*) row->data[6];
    field->charsetnr= uint2korr(pos);
    field->length=	(uint) uint4korr(pos+2);
    field->type=	(enum enum_field_types) pos[6];
    field->flags=	uint2korr(pos+7);
    field->decimals=  (uint) pos[9];

    if (IS_NUM(field->type))
      field->flags|= NUM_FLAG;
    if (default_value && row->data[7])
    {
      field->def=strmake_root(alloc,(char*) row->data[7], lengths[7]);
      field->def_length= lengths[7];
    }
    else
      field->def=0;
    field->max_length= 0;
  }
#ifndef DELETE_SUPPORT_OF_4_0_PROTOCOL
  else
  {
    cli_fetch_lengths(&lengths[0], row->data, default_value ? 6 : 5);
    field->org_table= field->table=  strdup_root(alloc,(char*) row->data[0]);
    field->name=   strdup_root(alloc,(char*) row->data[1]);
    field->length= (uint) uint3korr((uchar*) row->data[2]);
    field->type=   (enum enum_field_types) (uchar) row->data[3][0];

    field->catalog=(char*)  "";
    field->db=     (char*)  "";
    field->catalog_length= 0;
    field->db_length= 0;
    field->org_table_length=	field->table_length=	lengths[0];
    field->name_length=	lengths[1];

    if (server_capabilities & CLIENT_LONG_FLAG)
    {
      field->flags=   uint2korr((uchar*) row->data[4]);
      field->decimals=(uint) (uchar) row->data[4][2];
    }
    else
    {
      field->flags=   (uint) (uchar) row->data[4][0];
      field->decimals=(uint) (uchar) row->data[4][1];
    }
    if (IS_NUM(field->type))
      field->flags|= NUM_FLAG;
    if (default_value && row->data[5])
    {
      field->def=strdup_root(alloc,(char*) row->data[5]);
      field->def_length= lengths[5];
    }
    else
      field->def=0;
    field->max_length= 0;
  }
#endif /* DELETE_SUPPORT_OF_4_0_PROTOCOL */
  DBUG_RETURN(0);
}

/***************************************************************************
  Change field rows to field structs
***************************************************************************/

MYSQL_FIELD *
unpack_fields(MYSQL *mysql, MYSQL_ROWS *data,MEM_ROOT *alloc,uint fields,
	      my_bool default_value, uint server_capabilities)
{
  MYSQL_ROWS	*row;
  MYSQL_FIELD	*field,*result;
  DBUG_ENTER("unpack_fields");

  field= result= (MYSQL_FIELD*) alloc_root(alloc,
			   (uint) sizeof(*field)*fields);
  if (!result)
  {
    set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
    DBUG_RETURN(0);
  }
  memset(field, 0, sizeof(MYSQL_FIELD)*fields);
  for (row=data; row ; row = row->next,field++)
  {
    /* fields count may be wrong */
    DBUG_ASSERT((uint) (field - result) < fields);
    if (unpack_field(mysql, alloc, default_value, server_capabilities,
                     row, field))
    {
      DBUG_RETURN(NULL);
    }
  }
  DBUG_RETURN(result);
}


/**
  Read metadata resultset from server
  Memory allocated in a given allocator root.

  @param[IN]    mysql           connection handle
  @param[IN]    alloc           memory allocator root
  @param[IN]    field_count     total number of fields
  @param[IN]    field           number of columns in single field descriptor

  @retval an array of field rows

*/
MYSQL_FIELD *cli_read_metadata_ex(MYSQL *mysql, MEM_ROOT *alloc,
                                  ulong field_count, unsigned int field)
{
  ulong *len;
  uint  f;
  uchar *pos;
  MYSQL_FIELD *fields, *result;
  MYSQL_ROWS data;
  NET *net = &mysql->net;

  DBUG_ENTER("cli_read_metadata");

  len= (ulong*) alloc_root(alloc, sizeof(ulong)*field);

  fields= result= (MYSQL_FIELD*) alloc_root(alloc,
                          (uint) sizeof(MYSQL_FIELD)*field_count);
  if (!result)
  {
    set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
    DBUG_RETURN(0);
  }
  memset(fields, 0, sizeof(MYSQL_FIELD)*field_count);

  data.data= (MYSQL_ROW) alloc_root(alloc, sizeof(char *)*(field+1));
  memset(data.data, 0, sizeof(char *)*(field+1));

  /*
    In this below loop we read each column info as 1 single row
    and save it in mysql->fields array
  */
  for (f=0 ; f < field_count ; ++f)
  {
    if(read_one_row(mysql, field, data.data, len) == -1)
      DBUG_RETURN(NULL);
    if(unpack_field(mysql, alloc, 0, mysql->server_capabilities, &data,
                    fields++))
      DBUG_RETURN(NULL);
  }
  /* Read EOF packet in case of old client */
  if (!(mysql->server_capabilities & CLIENT_DEPRECATE_EOF))
  {
    if (packet_error == cli_safe_read(mysql, NULL))
      DBUG_RETURN(0);
    pos= net->read_pos;
    if (*pos == 254)
    {
      mysql->warning_count= uint2korr(pos + 1);
      mysql->server_status= uint2korr(pos + 3);
    }
  }
  DBUG_RETURN(result);
}


/**
  Read metadata resultset from server

  @param[IN]    mysql           connection handle
  @param[IN]    field_count     total number of fields
  @param[IN]    field           number of columns in single field descriptor

  @retval an array of field rows

*/
MYSQL_FIELD *cli_read_metadata(MYSQL *mysql, ulong field_count,
                               unsigned int field)
{
  return cli_read_metadata_ex(mysql, &mysql->field_alloc, field_count, field);
}


/* Read all rows (data) from server */

MYSQL_DATA *cli_read_rows(MYSQL *mysql,MYSQL_FIELD *mysql_fields,
			  unsigned int fields)
{
  uint	field;
  ulong pkt_len;
  ulong len;
  uchar *cp;
  char	*to, *end_to;
  MYSQL_DATA *result;
  MYSQL_ROWS **prev_ptr,*cur;
  NET *net = &mysql->net;
  my_bool is_data_packet;
  DBUG_ENTER("cli_read_rows");

  if ((pkt_len= cli_safe_read(mysql, &is_data_packet)) == packet_error)
    DBUG_RETURN(0);
  if (!(result=(MYSQL_DATA*) my_malloc(key_memory_MYSQL_DATA,
                                       sizeof(MYSQL_DATA),
				       MYF(MY_WME | MY_ZEROFILL))))
  {
    set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
    DBUG_RETURN(0);
  }
  init_alloc_root(PSI_NOT_INSTRUMENTED,
                  &result->alloc, 8192, 0); /* Assume rowlength < 8192 */
  result->alloc.min_malloc=sizeof(MYSQL_ROWS);
  prev_ptr= &result->data;
  result->rows=0;
  result->fields=fields;

  /*
    The last EOF packet is either a single 254 character or (in MySQL 4.1)
    254 followed by 1-7 status bytes or an OK packet starting with 0xFE
  */

  while (*(cp=net->read_pos) == 0 || is_data_packet)
  {
    result->rows++;
    if (!(cur= (MYSQL_ROWS*) alloc_root(&result->alloc,
					sizeof(MYSQL_ROWS))) ||
	!(cur->data= ((MYSQL_ROW)
		      alloc_root(&result->alloc,
				 (fields+1)*sizeof(char *)+pkt_len))))
    {
      free_rows(result);
      set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
      DBUG_RETURN(0);
    }
    *prev_ptr=cur;
    prev_ptr= &cur->next;
    to= (char*) (cur->data+fields+1);
    end_to=to+pkt_len-1;
    for (field=0 ; field < fields ; field++)
    {
      if ((len=(ulong) net_field_length(&cp)) == NULL_LENGTH)
      {						/* null field */
	cur->data[field] = 0;
      }
      else
      {
	cur->data[field] = to;
        if (len > (ulong) (end_to - to))
        {
          free_rows(result);
          set_mysql_error(mysql, CR_MALFORMED_PACKET, unknown_sqlstate);
          DBUG_RETURN(0);
        }
	memcpy(to,(char*) cp,len); to[len]=0;
	to+=len+1;
	cp+=len;
	if (mysql_fields)
	{
	  if (mysql_fields[field].max_length < len)
	    mysql_fields[field].max_length=len;
	}
      }
    }
    cur->data[field]=to;			/* End of last field */
    if ((pkt_len= cli_safe_read(mysql, &is_data_packet)) == packet_error)
    {
      free_rows(result);
      DBUG_RETURN(0);
    }
  }
  *prev_ptr=0;					/* last pointer is null */
  /* read EOF packet or OK packet if it is new client */
  if (pkt_len > 1)
  {
    if (mysql->server_capabilities & CLIENT_DEPRECATE_EOF &&
        !is_data_packet)
      read_ok_ex(mysql, pkt_len);
    else
    {
      mysql->warning_count= uint2korr(cp + 1);
      mysql->server_status= uint2korr(cp + 3);
    }

    DBUG_PRINT("info",("status: %u  warning_count:  %u",
                       mysql->server_status, mysql->warning_count));
  }

#if defined(CLIENT_PROTOCOL_TRACING)
  if (mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT);
  else
    MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
#endif
  DBUG_PRINT("exit", ("Got %lu rows", (ulong) result->rows));
  DBUG_RETURN(result);
}

/*
  Read one row. Uses packet buffer as storage for fields.
  When next packet is read, the previous field values are destroyed
*/


static int
read_one_row(MYSQL *mysql,uint fields,MYSQL_ROW row, ulong *lengths)
{
  uint field;
  ulong pkt_len,len;
  my_bool is_data_packet;
  uchar *pos, *prev_pos, *end_pos;
  NET *net= &mysql->net;

  if ((pkt_len= cli_safe_read(mysql, &is_data_packet)) == packet_error)
    return -1;
  if (net->read_pos[0] != 0x00 && !is_data_packet)
  {
    if (pkt_len > 1)				/* MySQL 4.1 protocol */
    {
      if (mysql->server_capabilities & CLIENT_DEPRECATE_EOF)
        read_ok_ex(mysql, pkt_len);
      else
      {
        mysql->warning_count= uint2korr(net->read_pos + 1);
        mysql->server_status= uint2korr(net->read_pos+3);
      }
    }
#if defined(CLIENT_PROTOCOL_TRACING)
    if (mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
      MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT);
    else
      MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
#endif
    return 1;				/* End of data */
  }
  prev_pos= 0;				/* allowed to write at packet[-1] */
  pos=net->read_pos;
  end_pos=pos+pkt_len;
  for (field=0 ; field < fields ; field++)
  {
    if ((len=(ulong) net_field_length(&pos)) == NULL_LENGTH)
    {						/* null field */
      row[field] = 0;
      *lengths++=0;
    }
    else
    {
      if (len > (ulong) (end_pos - pos))
      {
        set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
        return -1;
      }
      row[field] = (char*) pos;
      pos+=len;
      *lengths++=len;
    }
    if (prev_pos)
      *prev_pos=0;				/* Terminate prev field */
    prev_pos=pos;
  }
  row[field]=(char*) prev_pos+1;		/* End of last field */
  *prev_pos=0;					/* Terminate last field */
  return 0;
}


/****************************************************************************
  Init MySQL structure or allocate one
****************************************************************************/


MYSQL * STDCALL
mysql_init(MYSQL *mysql)
{
  if (mysql_server_init(0, NULL, NULL))
    return 0;
  if (!mysql)
  {
    if (!(mysql=(MYSQL*) my_malloc(key_memory_MYSQL,
                                   sizeof(*mysql),MYF(MY_WME | MY_ZEROFILL))))
    {
      set_mysql_error(NULL, CR_OUT_OF_MEMORY, unknown_sqlstate);
      return 0;
    }
    mysql->free_me=1;
  }
  else
    memset(mysql, 0, sizeof(*(mysql)));
  mysql->charset=default_client_charset_info;
  my_stpcpy(mysql->net.sqlstate, not_error_sqlstate);

  /*
    Only enable LOAD DATA INFILE by default if configured with option
    ENABLED_LOCAL_INFILE
  */

#if defined(ENABLED_LOCAL_INFILE) && !defined(MYSQL_SERVER)
  mysql->options.client_flag|= CLIENT_LOCAL_FILES;
#endif

#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
  mysql->options.shared_memory_base_name= (char*) def_shared_memory_base_name;
#endif

  mysql->options.methods_to_use= MYSQL_OPT_GUESS_CONNECTION;
  mysql->options.report_data_truncation= TRUE;  /* default */

  /* Initialize extensions. */
  if (!(mysql->extension= mysql_extension_init(mysql)))
  {
    set_mysql_error(NULL, CR_OUT_OF_MEMORY, unknown_sqlstate);
    return 0;
  }

  /*
    By default we don't reconnect because it could silently corrupt data (after
    reconnection you potentially lose table locks, user variables, session
    variables (transactions but they are specifically dealt with in
    mysql_reconnect()).
    This is a change: < 5.0.3 mysql->reconnect was set to 1 by default.
    How this change impacts existing apps:
    - existing apps which relyed on the default will see a behaviour change;
    they will have to set reconnect=1 after mysql_real_connect().
    - existing apps which explicitely asked for reconnection (the only way they
    could do it was by setting mysql.reconnect to 1 after mysql_real_connect())
    will not see a behaviour change.
    - existing apps which explicitely asked for no reconnection
    (mysql.reconnect=0) will not see a behaviour change.
  */
  mysql->reconnect= 0;

  return mysql;
}


/*
  MYSQL::extension handling (see sql_common.h for declaration
  of st_mysql_extension structure). 
*/

MYSQL_EXTENSION* mysql_extension_init(MYSQL *mysql __attribute__((unused)))
{
  MYSQL_EXTENSION *ext;

  ext= my_malloc(PSI_NOT_INSTRUMENTED,
                 sizeof(MYSQL_EXTENSION), MYF(MY_WME | MY_ZEROFILL));
  return ext;
}


void mysql_extension_free(struct st_mysql_extension* ext)
{
  if (!ext)
    return;
  if (ext->trace_data)
    my_free(ext->trace_data);

  // free state change related resources.
  free_state_change_info(ext);

  my_free(ext);
}


/*
  Fill in SSL part of MYSQL structure and set 'use_ssl' flag.
  NB! Errors are not reported until you do mysql_real_connect.
*/

my_bool STDCALL
mysql_ssl_set(MYSQL *mysql __attribute__((unused)) ,
	      const char *key __attribute__((unused)),
	      const char *cert __attribute__((unused)),
	      const char *ca __attribute__((unused)),
	      const char *capath __attribute__((unused)),
	      const char *cipher __attribute__((unused)))
{
  my_bool result= 0;
  DBUG_ENTER("mysql_ssl_set");
#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)
  result=
    mysql_options(mysql, MYSQL_OPT_SSL_KEY,    key)    +
    mysql_options(mysql, MYSQL_OPT_SSL_CERT,   cert)   +
    mysql_options(mysql, MYSQL_OPT_SSL_CA,     ca)     +
    mysql_options(mysql, MYSQL_OPT_SSL_CAPATH, capath) +
    mysql_options(mysql, MYSQL_OPT_SSL_CIPHER, cipher)
    ? 1 : 0;
#endif
    DBUG_RETURN(result);
}


/*
  Free strings in the SSL structure and clear 'use_ssl' flag.
  NB! Errors are not reported until you do mysql_real_connect.
*/

#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)

static void
mysql_ssl_free(MYSQL *mysql __attribute__((unused)))
{
  struct st_VioSSLFd *ssl_fd= (struct st_VioSSLFd*) mysql->connector_fd;
  DBUG_ENTER("mysql_ssl_free");

  my_free(mysql->options.ssl_key);
  my_free(mysql->options.ssl_cert);
  my_free(mysql->options.ssl_ca);
  my_free(mysql->options.ssl_capath);
  my_free(mysql->options.ssl_cipher);
  if (mysql->options.extension)
  {
    my_free(mysql->options.extension->ssl_crl);
    my_free(mysql->options.extension->ssl_crlpath);
  }
  if (ssl_fd)
    SSL_CTX_free(ssl_fd->ssl_context);
  my_free(mysql->connector_fd);
  mysql->options.ssl_key = 0;
  mysql->options.ssl_cert = 0;
  mysql->options.ssl_ca = 0;
  mysql->options.ssl_capath = 0;
  mysql->options.ssl_cipher= 0;
  if (mysql->options.extension)
  {
    mysql->options.extension->ssl_crl = 0;
    mysql->options.extension->ssl_crlpath = 0;
  }
  mysql->options.use_ssl = FALSE;
  mysql->connector_fd = 0;
  DBUG_VOID_RETURN;
}

#endif /* HAVE_OPENSSL && !EMBEDDED_LIBRARY */

/*
  Return the SSL cipher (if any) used for current
  connection to the server.

  SYNOPSYS
    mysql_get_ssl_cipher()
      mysql pointer to the mysql connection

*/

const char * STDCALL
mysql_get_ssl_cipher(MYSQL *mysql __attribute__((unused)))
{
  DBUG_ENTER("mysql_get_ssl_cipher");
#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)
  if (mysql->net.vio && mysql->net.vio->ssl_arg)
    DBUG_RETURN(SSL_get_cipher_name((SSL*)mysql->net.vio->ssl_arg));
#endif /* HAVE_OPENSSL && !EMBEDDED_LIBRARY */
  DBUG_RETURN(NULL);
}


/*
  Check the server's (subject) Common Name against the
  hostname we connected to

  SYNOPSIS
  ssl_verify_server_cert()
    vio              pointer to a SSL connected vio
    server_hostname  name of the server that we connected to
    errptr           if we fail, we'll return (a pointer to a string
                     describing) the reason here

  RETURN VALUES
   0 Success
   1 Failed to validate server

 */

#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)

static int ssl_verify_server_cert(Vio *vio, const char* server_hostname, const char **errptr)
{
  SSL *ssl;
  X509 *server_cert;
  char *cp1, *cp2;
  char buf[256];
  DBUG_ENTER("ssl_verify_server_cert");
  DBUG_PRINT("enter", ("server_hostname: %s", server_hostname));

  if (!(ssl= (SSL*)vio->ssl_arg))
  {
    *errptr= "No SSL pointer found";
    DBUG_RETURN(1);
  }

  if (!server_hostname)
  {
    *errptr= "No server hostname supplied";
    DBUG_RETURN(1);
  }

  if (!(server_cert= SSL_get_peer_certificate(ssl)))
  {
    *errptr= "Could not get server certificate";
    DBUG_RETURN(1);
  }

  if (X509_V_OK != SSL_get_verify_result(ssl))
  {
    *errptr= "Failed to verify the server certificate";
    X509_free(server_cert);
    DBUG_RETURN(1);
  }
  /*
    We already know that the certificate exchanged was valid; the SSL library
    handled that. Now we need to verify that the contents of the certificate
    are what we expect.
  */

  X509_NAME_oneline(X509_get_subject_name(server_cert), buf, sizeof(buf));
  X509_free (server_cert);

  DBUG_PRINT("info", ("hostname in cert: %s", buf));
  cp1= strstr(buf, "/CN=");
  if (cp1)
  {
    cp1+= 4; /* Skip the "/CN=" that we found */
    /* Search for next / which might be the delimiter for email */
    cp2= strchr(cp1, '/');
    if (cp2)
      *cp2= '\0';
    DBUG_PRINT("info", ("Server hostname in cert: %s", cp1));
    if (!strcmp(cp1, server_hostname))
    {
      /* Success */
      DBUG_RETURN(0);
    }
  }
  *errptr= "SSL certificate validation failure";
  DBUG_RETURN(1);
}

#endif /* HAVE_OPENSSL && !EMBEDDED_LIBRARY */


/*
  Note that the mysql argument must be initialized with mysql_init()
  before calling mysql_real_connect !
*/

static my_bool cli_read_query_result(MYSQL *mysql);
static MYSQL_RES *cli_use_result(MYSQL *mysql);

int cli_read_change_user_result(MYSQL *mysql)
{
  return cli_safe_read(mysql, NULL);
}

static MYSQL_METHODS client_methods=
{
  cli_read_query_result,                       /* read_query_result */
  cli_advanced_command,                        /* advanced_command */
  cli_read_rows,                               /* read_rows */
  cli_use_result,                              /* use_result */
  cli_fetch_lengths,                           /* fetch_lengths */
  cli_flush_use_result,                        /* flush_use_result */
  cli_read_change_user_result                  /* read_change_user_result */
#ifndef MYSQL_SERVER
  ,cli_list_fields,                            /* list_fields */
  cli_read_prepare_result,                     /* read_prepare_result */
  cli_stmt_execute,                            /* stmt_execute */
  cli_read_binary_rows,                        /* read_binary_rows */
  cli_unbuffered_fetch,                        /* unbuffered_fetch */
  NULL,                                        /* free_embedded_thd */
  cli_read_statistics,                         /* read_statistics */
  cli_read_query_result,                       /* next_result */
  cli_read_binary_rows,                        /* read_rows_from_cursor */
  free_rows
#endif
};



typedef enum my_cs_match_type_enum
{
  /* MySQL and OS charsets are fully compatible */
  my_cs_exact,
  /* MySQL charset is very close to OS charset  */
  my_cs_approx,
  /*
    MySQL knows this charset, but it is not supported as client character set.
  */
  my_cs_unsupp
} my_cs_match_type;


typedef struct str2str_st
{
  const char *os_name;
  const char *my_name;
  my_cs_match_type param;
} MY_CSET_OS_NAME;

const MY_CSET_OS_NAME charsets[]=
{
#ifdef _WIN32
  {"cp437",          "cp850",    my_cs_approx},
  {"cp850",          "cp850",    my_cs_exact},
  {"cp852",          "cp852",    my_cs_exact},
  {"cp858",          "cp850",    my_cs_approx},
  {"cp866",          "cp866",    my_cs_exact},
  {"cp874",          "tis620",   my_cs_approx},
  {"cp932",          "cp932",    my_cs_exact},
  {"cp936",          "gbk",      my_cs_approx},
  {"cp949",          "euckr",    my_cs_approx},
  {"cp950",          "big5",     my_cs_exact},
  {"cp1200",         "utf16le",  my_cs_unsupp},
  {"cp1201",         "utf16",    my_cs_unsupp},
  {"cp1250",         "cp1250",   my_cs_exact},
  {"cp1251",         "cp1251",   my_cs_exact},
  {"cp1252",         "latin1",   my_cs_exact},
  {"cp1253",         "greek",    my_cs_exact},
  {"cp1254",         "latin5",   my_cs_exact},
  {"cp1255",         "hebrew",   my_cs_approx},
  {"cp1256",         "cp1256",   my_cs_exact},
  {"cp1257",         "cp1257",   my_cs_exact},
  {"cp10000",        "macroman", my_cs_exact},
  {"cp10001",        "sjis",     my_cs_approx},
  {"cp10002",        "big5",     my_cs_approx},
  {"cp10008",        "gb2312",   my_cs_approx},
  {"cp10021",        "tis620",   my_cs_approx},
  {"cp10029",        "macce",    my_cs_exact},
  {"cp12001",        "utf32",    my_cs_unsupp},
  {"cp20107",        "swe7",     my_cs_exact},
  {"cp20127",        "latin1",   my_cs_approx},
  {"cp20866",        "koi8r",    my_cs_exact},
  {"cp20932",        "ujis",     my_cs_exact},
  {"cp20936",        "gb2312",   my_cs_approx},
  {"cp20949",        "euckr",    my_cs_approx},
  {"cp21866",        "koi8u",    my_cs_exact},
  {"cp28591",        "latin1",   my_cs_approx},
  {"cp28592",        "latin2",   my_cs_exact},
  {"cp28597",        "greek",    my_cs_exact},
  {"cp28598",        "hebrew",   my_cs_exact},
  {"cp28599",        "latin5",   my_cs_exact},
  {"cp28603",        "latin7",   my_cs_exact},
#ifdef UNCOMMENT_THIS_WHEN_WL_4579_IS_DONE
  {"cp28605",        "latin9",   my_cs_exact},
#endif
  {"cp38598",        "hebrew",   my_cs_exact},
  {"cp51932",        "ujis",     my_cs_exact},
  {"cp51936",        "gb2312",   my_cs_exact},
  {"cp51949",        "euckr",    my_cs_exact},
  {"cp51950",        "big5",     my_cs_exact},
  {"cp54936",        "gb18030",  my_cs_exact},
  {"cp65001",        "utf8",     my_cs_exact},

#else /* not Windows */

  {"646",            "latin1",   my_cs_approx}, /* Default on Solaris */
  {"ANSI_X3.4-1968", "latin1",   my_cs_approx},
  {"ansi1251",       "cp1251",   my_cs_exact},
  {"armscii8",       "armscii8", my_cs_exact},
  {"armscii-8",      "armscii8", my_cs_exact},
  {"ASCII",          "latin1",   my_cs_approx},
  {"Big5",           "big5",     my_cs_exact},
  {"cp1251",         "cp1251",   my_cs_exact},
  {"cp1255",         "hebrew",   my_cs_approx},
  {"CP866",          "cp866",    my_cs_exact},
  {"eucCN",          "gb2312",   my_cs_exact},
  {"euc-CN",         "gb2312",   my_cs_exact},
  {"eucJP",          "ujis",     my_cs_exact},
  {"euc-JP",         "ujis",     my_cs_exact},
  {"eucKR",          "euckr",    my_cs_exact},
  {"euc-KR",         "euckr",    my_cs_exact},
  {"gb18030",        "gb18030",  my_cs_exact},
  {"gb2312",         "gb2312",   my_cs_exact},
  {"gbk",            "gbk",      my_cs_exact},
  {"georgianps",     "geostd8",  my_cs_exact},
  {"georgian-ps",    "geostd8",  my_cs_exact},
  {"IBM-1252",       "cp1252",   my_cs_exact},

  {"iso88591",       "latin1",   my_cs_approx},
  {"ISO_8859-1",     "latin1",   my_cs_approx},
  {"ISO8859-1",      "latin1",   my_cs_approx},
  {"ISO-8859-1",     "latin1",   my_cs_approx},

  {"iso885913",      "latin7",   my_cs_exact},
  {"ISO_8859-13",    "latin7",   my_cs_exact},
  {"ISO8859-13",     "latin7",   my_cs_exact},
  {"ISO-8859-13",    "latin7",   my_cs_exact},

#ifdef UNCOMMENT_THIS_WHEN_WL_4579_IS_DONE
  {"iso885915",      "latin9",   my_cs_exact},
  {"ISO_8859-15",    "latin9",   my_cs_exact},
  {"ISO8859-15",     "latin9",   my_cs_exact},
  {"ISO-8859-15",    "latin9",   my_cs_exact},
#endif

  {"iso88592",       "latin2",   my_cs_exact},
  {"ISO_8859-2",     "latin2",   my_cs_exact},
  {"ISO8859-2",      "latin2",   my_cs_exact},
  {"ISO-8859-2",     "latin2",   my_cs_exact},

  {"iso88597",       "greek",    my_cs_exact},
  {"ISO_8859-7",     "greek",    my_cs_exact},
  {"ISO8859-7",      "greek",    my_cs_exact},
  {"ISO-8859-7",     "greek",    my_cs_exact},

  {"iso88598",       "hebrew",   my_cs_exact},
  {"ISO_8859-8",     "hebrew",   my_cs_exact},
  {"ISO8859-8",      "hebrew",   my_cs_exact},
  {"ISO-8859-8",     "hebrew",   my_cs_exact},

  {"iso88599",       "latin5",   my_cs_exact},
  {"ISO_8859-9",     "latin5",   my_cs_exact},
  {"ISO8859-9",      "latin5",   my_cs_exact},
  {"ISO-8859-9",     "latin5",   my_cs_exact},

  {"koi8r",          "koi8r",    my_cs_exact},
  {"KOI8-R",         "koi8r",    my_cs_exact},
  {"koi8u",          "koi8u",    my_cs_exact},
  {"KOI8-U",         "koi8u",    my_cs_exact},

  {"roman8",         "hp8",      my_cs_exact}, /* Default on HP UX */

  {"Shift_JIS",      "sjis",     my_cs_exact},
  {"SJIS",           "sjis",     my_cs_exact},
  {"shiftjisx0213",  "sjis",     my_cs_exact},
  
  {"tis620",         "tis620",   my_cs_exact},
  {"tis-620",        "tis620",   my_cs_exact},

  {"ujis",           "ujis",     my_cs_exact},

  {"US-ASCII",       "latin1",   my_cs_approx},

  {"utf8",           "utf8",     my_cs_exact},
  {"utf-8",          "utf8",     my_cs_exact},
#endif
  {NULL,             NULL,       0}
};


static const char *
my_os_charset_to_mysql_charset(const char *csname)
{
  const MY_CSET_OS_NAME *csp;
  for (csp= charsets; csp->os_name; csp++)
  {
    if (!my_strcasecmp(&my_charset_latin1, csp->os_name, csname))
    {
      switch (csp->param)
      {
      case my_cs_exact:
        return csp->my_name;

      case my_cs_approx:
        /*
          Maybe we should print a warning eventually:
          character set correspondence is not exact.
        */
        return csp->my_name;

      default:
        my_printf_error(ER_UNKNOWN_ERROR,
                        "OS character set '%s'"
                        " is not supported by MySQL client",
                         MYF(0), csp->my_name);
        goto def;
      }
    }
  }

  my_printf_error(ER_UNKNOWN_ERROR,
                  "Unknown OS character set '%s'.",
                  MYF(0), csname);

def:
  csname= MYSQL_DEFAULT_CHARSET_NAME;
  my_printf_error(ER_UNKNOWN_ERROR,
                  "Switching to the default character set '%s'.",
                  MYF(0), csname);
  return csname;
}


#ifndef _WIN32
#include <stdlib.h> /* for getenv() */
#ifdef HAVE_LANGINFO_H
#include <langinfo.h>
#endif
#include <locale.h>
#endif /* _WIN32 */


static int
mysql_autodetect_character_set(MYSQL *mysql)
{
  const char *csname= MYSQL_DEFAULT_CHARSET_NAME;

#ifdef _WIN32
  char cpbuf[64];
  {
    my_snprintf(cpbuf, sizeof(cpbuf), "cp%d", (int) GetConsoleCP());
    csname= my_os_charset_to_mysql_charset(cpbuf);
  }
#elif defined(HAVE_NL_LANGINFO)
  {
    if (setlocale(LC_CTYPE, "") && (csname= nl_langinfo(CODESET)))
      csname= my_os_charset_to_mysql_charset(csname);
  }
#endif

  if (mysql->options.charset_name)
    my_free(mysql->options.charset_name);
  if (!(mysql->options.charset_name= my_strdup(key_memory_mysql_options,
                                               csname, MYF(MY_WME))))
    return 1;
  return 0;
}


static void
mysql_set_character_set_with_default_collation(MYSQL *mysql)
{
  const char *save= charsets_dir;
  if (mysql->options.charset_dir)
    charsets_dir=mysql->options.charset_dir;

  if ((mysql->charset= get_charset_by_csname(mysql->options.charset_name,
                                             MY_CS_PRIMARY, MYF(MY_WME))))
  {
    /* Try to set compiled default collation when it's possible. */
    CHARSET_INFO *collation;
    if ((collation= 
         get_charset_by_name(MYSQL_DEFAULT_COLLATION_NAME, MYF(MY_WME))) &&
                             my_charset_same(mysql->charset, collation))
    {
      mysql->charset= collation;
    }
    else
    {
      /*
        Default compiled collation not found, or is not applicable
        to the requested character set.
        Continue with the default collation of the character set.
      */
    }
  }
  charsets_dir= save;
}


C_MODE_START
int mysql_init_character_set(MYSQL *mysql)
{
  /* Set character set */
  if (!mysql->options.charset_name)
  {
    if (!(mysql->options.charset_name= 
       my_strdup(key_memory_mysql_options,
                 MYSQL_DEFAULT_CHARSET_NAME,MYF(MY_WME))))
      return 1;
  }
  else if (!strcmp(mysql->options.charset_name,
                   MYSQL_AUTODETECT_CHARSET_NAME) &&
            mysql_autodetect_character_set(mysql))
    return 1;

  mysql_set_character_set_with_default_collation(mysql);

  if (!mysql->charset)
  {
    if (mysql->options.charset_dir)
      set_mysql_extended_error(mysql, CR_CANT_READ_CHARSET, unknown_sqlstate,
                               ER(CR_CANT_READ_CHARSET),
                               mysql->options.charset_name,
                               mysql->options.charset_dir);
    else
    {
      char cs_dir_name[FN_REFLEN];
      get_charsets_dir(cs_dir_name);
      set_mysql_extended_error(mysql, CR_CANT_READ_CHARSET, unknown_sqlstate,
                               ER(CR_CANT_READ_CHARSET),
                               mysql->options.charset_name,
                               cs_dir_name);
    }
    return 1;
  }
  return 0;
}
C_MODE_END

/*********** client side authentication support **************************/

typedef struct st_mysql_client_plugin_AUTHENTICATION auth_plugin_t;
static int client_mpvio_write_packet(struct st_plugin_vio*, const uchar*, int);
static int native_password_auth_client(MYSQL_PLUGIN_VIO *vio, MYSQL *mysql);
static int clear_password_auth_client(MYSQL_PLUGIN_VIO *vio, MYSQL *mysql);

static auth_plugin_t native_password_client_plugin=
{
  MYSQL_CLIENT_AUTHENTICATION_PLUGIN,
  MYSQL_CLIENT_AUTHENTICATION_PLUGIN_INTERFACE_VERSION,
  native_password_plugin_name,
  "R.J.Silk, Sergei Golubchik",
  "Native MySQL authentication",
  {1, 0, 0},
  "GPL",
  NULL,
  NULL,
  NULL,
  NULL,
  native_password_auth_client
};

static auth_plugin_t clear_password_client_plugin=
{
  MYSQL_CLIENT_AUTHENTICATION_PLUGIN,
  MYSQL_CLIENT_AUTHENTICATION_PLUGIN_INTERFACE_VERSION,
  "mysql_clear_password",
  "Georgi Kodinov",
  "Clear password authentication plugin",
  {0,1,0},
  "GPL",
  NULL,
  NULL,
  NULL,
  NULL,
  clear_password_auth_client
};

#if defined(HAVE_OPENSSL)
static auth_plugin_t sha256_password_client_plugin=
{
  MYSQL_CLIENT_AUTHENTICATION_PLUGIN,
  MYSQL_CLIENT_AUTHENTICATION_PLUGIN_INTERFACE_VERSION,
  "sha256_password",
  "Oracle Inc",
  "SHA256 based authentication with salt",
  {1, 0, 0},
  "GPL",
  NULL,
  sha256_password_init,
  sha256_password_deinit,
  NULL,
  sha256_password_auth_client
};
#endif
#ifdef AUTHENTICATION_WIN
extern auth_plugin_t win_auth_client_plugin;
#endif

/*
  Test trace plugin can be used only in debug builds. In non-debug ones
  it is ignored, even if it was enabled by build options (TEST_TRACE_PLUGIN macro).
*/

#if defined(CLIENT_PROTOCOL_TRACING) \
    && defined(TEST_TRACE_PLUGIN) \
    && !defined(DBUG_OFF)
extern auth_plugin_t test_trace_plugin;
#endif

struct st_mysql_client_plugin *mysql_client_builtins[]=
{
  (struct st_mysql_client_plugin *)&native_password_client_plugin,
  (struct st_mysql_client_plugin *)&clear_password_client_plugin,
#if defined(HAVE_OPENSSL)
  (struct st_mysql_client_plugin *) &sha256_password_client_plugin,
#endif
#ifdef AUTHENTICATION_WIN
  (struct st_mysql_client_plugin *)&win_auth_client_plugin,
#endif
#if defined(CLIENT_PROTOCOL_TRACING) \
    && defined(TEST_TRACE_PLUGIN) \
    && !defined(DBUG_OFF)
  (struct st_mysql_client_plugin *)&test_trace_plugin,
#endif
  0
};


static uchar *
write_length_encoded_string3(uchar *buf, char *string, size_t length)
{
  buf= net_store_length(buf, length);
  memcpy(buf, string, length);
  buf+= length;
  return buf;
}


uchar *
send_client_connect_attrs(MYSQL *mysql, uchar *buf)
{
  /* check if the server supports connection attributes */
  if (mysql->server_capabilities & CLIENT_CONNECT_ATTRS)
  {

    /* Always store the length if the client supports it */
    buf= net_store_length(buf,
                          mysql->options.extension ?
                          mysql->options.extension->connection_attributes_length :
                          0);

    /* check if we have connection attributes */
    if (mysql->options.extension &&
        my_hash_inited(&mysql->options.extension->connection_attributes))
    {
      HASH *attrs= &mysql->options.extension->connection_attributes;
      ulong idx;

      /* loop over and dump the connection attributes */
      for (idx= 0; idx < attrs->records; idx++)
      {
        LEX_STRING *attr= (LEX_STRING *) my_hash_element(attrs, idx);
        LEX_STRING *key= attr, *value= attr + 1;

        /* we can't have zero length keys */
        DBUG_ASSERT(key->length);

        buf= write_length_encoded_string3(buf, key->str, key->length);
        buf= write_length_encoded_string3(buf, value->str, value->length);
      }
    }
  }
  return buf;
}


static size_t get_length_store_length(size_t length)
{
  /* as defined in net_store_length */
  #define MAX_VARIABLE_STRING_LENGTH 9
  uchar length_buffer[MAX_VARIABLE_STRING_LENGTH], *ptr;

  ptr= net_store_length(length_buffer, length);

  return ptr - &length_buffer[0];
}


/* this is a "superset" of MYSQL_PLUGIN_VIO, in C++ I use inheritance */
typedef struct {
  int (*read_packet)(struct st_plugin_vio *vio, uchar **buf);
  int (*write_packet)(struct st_plugin_vio *vio, const uchar *pkt, int pkt_len);
  void (*info)(struct st_plugin_vio *vio, struct st_plugin_vio_info *info);
  /* -= end of MYSQL_PLUGIN_VIO =- */
  MYSQL *mysql;
  auth_plugin_t *plugin;            /**< what plugin we're under */
  const char *db;
  struct {
    uchar *pkt;                     /**< pointer into NET::buff */
    uint pkt_len;
  } cached_server_reply;
  int packets_read, packets_written; /**< counters for send/received packets */
  int mysql_change_user;            /**< if it's mysql_change_user() */
  int last_read_packet_len;         /**< the length of the last *read* packet */
} MCPVIO_EXT;


/*
  Write 1-8 bytes of string length header infromation to dest depending on
  value of src_len, then copy src_len bytes from src to dest.
 
 @param dest Destination buffer of size src_len+8
 @param dest_end One byte past the end of the dest buffer
 @param src Source buff of size src_len
 @param src_end One byte past the end of the src buffer
 
 @return pointer dest+src_len+header size or NULL if 
*/

char *write_length_encoded_string4(char *dest, char *dest_end, char *src,
                                  char *src_end)
{
  size_t src_len= (size_t)(src_end - src);
  uchar *to= net_store_length((uchar*) dest, src_len);
  if ((char*)(to + src_len) >= dest_end)
    return NULL;
  memcpy(to, src, src_len);
  return (char*)(to + src_len);
}


/*
  Write 1 byte of string length header information to dest and
  copy src_len bytes from src to dest.
*/
char *write_string(char *dest, char *dest_end, char *src, char *src_end)
{
  size_t src_len= (size_t)(src_end - src);
  uchar *to= NULL;
  if (src_len >= 251)
    return NULL;
  *dest=(uchar) src_len;
  to= (uchar*) dest+1;
  if ((char*)(to + src_len) >= dest_end)
    return NULL;
  memcpy(to, src, src_len);
  return (char*)(to + src_len);
}
/**
  sends a COM_CHANGE_USER command with a caller provided payload

  Packet format:
   
    Bytes       Content
    -----       ----
    n           user name - \0-terminated string
    n           password
                  3.23 scramble - \0-terminated string (9 bytes)
                  otherwise - length (1 byte) coded
    n           database name - \0-terminated string
    2           character set number (if the server >= 4.1.x)
    n           client auth plugin name - \0-terminated string,
                  (if the server supports plugin auth)

  @retval 0 ok
  @retval 1 error
*/
static int send_change_user_packet(MCPVIO_EXT *mpvio,
                                   const uchar *data, int data_len)
{
  MYSQL *mysql= mpvio->mysql;
  char *buff, *end;
  int res= 1;
  size_t connect_attrs_len=
    (mysql->server_capabilities & CLIENT_CONNECT_ATTRS &&
     mysql->options.extension) ?
    mysql->options.extension->connection_attributes_length : 0;

  buff= my_alloca(USERNAME_LENGTH + data_len + 1 + NAME_LEN + 2 + NAME_LEN +
                  connect_attrs_len + 9 /* for the length of the attrs */);

  end= strmake(buff, mysql->user, USERNAME_LENGTH) + 1;

  if (!data_len)
    *end++= 0;
  else
  {
    DBUG_ASSERT(data_len <= 255);
    if (data_len > 255)
    {
      set_mysql_error(mysql, CR_MALFORMED_PACKET, unknown_sqlstate);
      goto error;
    }
    *end++= data_len;
    memcpy(end, data, data_len);
    end+= data_len;
  }
  end= strmake(end, mpvio->db ? mpvio->db : "", NAME_LEN) + 1;

  if (mysql->server_capabilities & CLIENT_PROTOCOL_41)
  {
    int2store((uchar*) end, (ushort) mysql->charset->number);
    end+= 2;
  }

  if (mysql->server_capabilities & CLIENT_PLUGIN_AUTH)
    end= strmake(end, mpvio->plugin->name, NAME_LEN) + 1;

  end= (char *) send_client_connect_attrs(mysql, (uchar *) end);

  res= simple_command(mysql, COM_CHANGE_USER,
                      (uchar*)buff, (ulong)(end-buff), 1);

error:
  my_afree(buff);
  return res;
}

/**
  Fill in the beginning of the client reply packet.

  Used to fill in the beginning of the client reply packet
  or the ssl request packet.

  @param       mysql     The mysql handler to operate
  @param[out]  buff      The buffer to receive the packet
  @param       buff_size The max size of the buffer. Used in debug only.
  @return                one past to where the buffer is filled

*/
static char *
mysql_fill_packet_header(MYSQL *mysql, char *buff,
                         size_t buff_size  __attribute__((unused)))
{
  NET *net= &mysql->net;
  char *end;
  uchar *buff_p= (uchar*) buff;
  (void)buff_size; /* avoid warnings */

  if (mysql->client_flag & CLIENT_PROTOCOL_41)
  {
    /* 4.1 server and 4.1 client has a 32 byte option flag */
    DBUG_ASSERT(buff_size >= 32);

    int4store(buff_p, mysql->client_flag);
    int4store(buff_p + 4, net->max_packet_size);
    buff[8]= (char) mysql->charset->number;
    memset(buff + 9, 0, 32 - 9);
    end= buff + 32;
  }
  else
  {
    DBUG_ASSERT(buff_size >= 5);
    DBUG_ASSERT(mysql->client_flag <= UINT_MAX16);

    int2store(buff_p, (uint16) mysql->client_flag);
    int3store(buff_p + 2, net->max_packet_size);
    end= buff + 5;
  }
  return end;
}


/**
  Calcualtes client capabilities in effect (mysql->client_flag)
  
  Needs to be called immediately after receiving the server handshake packet.

  @param  mysql   the connection context
  @param  db      The database specified by the client app
  @param  db      The client flag as specified by the client app
  */

static void
cli_calculate_client_flag(MYSQL *mysql, const char *db, ulong client_flag)
{
  mysql->client_flag= client_flag;
  mysql->client_flag|= mysql->options.client_flag;
  mysql->client_flag|= CLIENT_CAPABILITIES;

  if (mysql->client_flag & CLIENT_MULTI_STATEMENTS)
    mysql->client_flag|= CLIENT_MULTI_RESULTS;

#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)
  /* consider SSL if any of the SSL mysql_options() is issued */
  if (mysql->options.ssl_key || mysql->options.ssl_cert ||
      mysql->options.ssl_ca || mysql->options.ssl_capath ||
      mysql->options.ssl_cipher ||
      (mysql->options.extension && mysql->options.extension->ssl_crl) ||
      (mysql->options.extension && mysql->options.extension->ssl_crlpath) ||
      (mysql->options.extension && mysql->options.extension->ssl_enforce))
      mysql->options.use_ssl= TRUE;
  if (mysql->options.use_ssl)
    mysql->client_flag |= CLIENT_SSL;
#endif /* HAVE_OPENSSL && !EMBEDDED_LIBRARY*/
  if (db)
    mysql->client_flag|= CLIENT_CONNECT_WITH_DB;
  else
    mysql->client_flag&= ~CLIENT_CONNECT_WITH_DB;

  /* Remove options that server doesn't support */
  mysql->client_flag= mysql->client_flag &
    (~(CLIENT_COMPRESS | CLIENT_SSL | CLIENT_PROTOCOL_41)
    | mysql->server_capabilities);

#ifndef HAVE_COMPRESS
  mysql->client_flag&= ~CLIENT_COMPRESS;
#endif
}


/**
Establishes SSL if requested and supported.

@param  mysql   the connection handle
@retval 0       success
@retval 1       failure
*/
static int
cli_establish_ssl(MYSQL *mysql)
{
#ifdef HAVE_OPENSSL
  NET *net= &mysql->net;

  if (mysql->options.extension && mysql->options.extension->ssl_enforce)
  {
    /*
    ssl_enforce=1 means enforce ssl
    Don't fallback on unencrypted connection.
    */
    /* can't turn enforce on without turning on use_ssl too */
    DBUG_ASSERT(mysql->options.use_ssl);
    /* enforce=true takes precendence over use=false */
    if (!(mysql->server_capabilities & CLIENT_SSL))
    {
      set_mysql_extended_error(mysql, CR_SSL_CONNECTION_ERROR, unknown_sqlstate,
                               ER(CR_SSL_CONNECTION_ERROR),
                               "SSL is required but the server doesn't "
                               "support it"
                               );
      goto error;
    }
  }

  /*

  use_ssl=0 => Disable ssl and connect using unencrypted channel if server
  allows it

  use_ssl=1, ssl_enforce=0 (default) => attempt ssl connection if possible but
  fallback on unencrypted connection if possible.

  */
  if ((mysql->server_capabilities & CLIENT_SSL) && mysql->options.use_ssl)
  {
    /* Do the SSL layering. */
    struct st_mysql_options *options= &mysql->options;
    struct st_VioSSLFd *ssl_fd;
    enum enum_ssl_init_error ssl_init_error;
    const char *cert_error;
    unsigned long ssl_error;
    char buff[33], *end;

    end= mysql_fill_packet_header(mysql, buff, sizeof(buff));

    if (!mysql->options.ssl_cipher)
    {
      SET_OPTION(ssl_cipher, default_ssl_cipher);
    }

    /*
    Send mysql->client_flag, max_packet_size - unencrypted otherwise
    the server does not know we want to do SSL
    */
    MYSQL_TRACE(SEND_SSL_REQUEST, mysql, (end - buff, (const unsigned char*) buff));
    if (my_net_write(net, (uchar*) buff, (size_t) (end - buff)) || net_flush(net))
    {
      set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                               ER(CR_SERVER_LOST_EXTENDED),
                               "sending connection information to server",
                               errno);
      goto error;
    }

    MYSQL_TRACE_STAGE(mysql, SSL_NEGOTIATION);

    /* Create the VioSSLConnectorFd - init SSL and load certs */
    if (!(ssl_fd= new_VioSSLConnectorFd(options->ssl_key,
      options->ssl_cert,
      options->ssl_ca,
      options->ssl_capath,
      options->ssl_cipher,
      &ssl_init_error,
      options->extension ?
      options->extension->ssl_crl : NULL,
      options->extension ?
      options->extension->ssl_crlpath : NULL)))
    {
      set_mysql_extended_error(mysql, CR_SSL_CONNECTION_ERROR, unknown_sqlstate,
                               ER(CR_SSL_CONNECTION_ERROR), sslGetErrString(ssl_init_error));
      goto error;
    }
    mysql->connector_fd= (unsigned char *) ssl_fd;

    /* Connect to the server */
    DBUG_PRINT("info", ("IO layer change in progress..."));
    MYSQL_TRACE(SSL_CONNECT, mysql, ());
    if (sslconnect(ssl_fd, net->vio,
      (long) (mysql->options.connect_timeout), &ssl_error))
    {
      char buf[512];
      ERR_error_string_n(ssl_error, buf, 512);
      buf[511]= 0;
      set_mysql_extended_error(mysql, CR_SSL_CONNECTION_ERROR, unknown_sqlstate,
                               ER(CR_SSL_CONNECTION_ERROR),
                               buf);
      goto error;
    }
    DBUG_PRINT("info", ("IO layer change done!"));

    /* Verify server cert */
    if ((mysql->client_flag & CLIENT_SSL_VERIFY_SERVER_CERT) &&
        ssl_verify_server_cert(net->vio, mysql->host, &cert_error))
    {
      set_mysql_extended_error(mysql, CR_SSL_CONNECTION_ERROR, unknown_sqlstate,
                               ER(CR_SSL_CONNECTION_ERROR), cert_error);
      goto error;
    }

    MYSQL_TRACE(SSL_CONNECTED, mysql, ());
    MYSQL_TRACE_STAGE(mysql, AUTHENTICATE);
  }

  return 0;

error:
  return 1;

#else
  (void)mysql; /* avoid warning */

#endif /* HAVE_OPENSSL */
  return 0;
}


#define MAX_CONNECTION_ATTR_STORAGE_LENGTH 65536

/**
  sends a client authentication packet (second packet in the 3-way handshake)

  Packet format (when the server is 4.0 or earlier):

    Bytes       Content
    -----       ----
    2           client capabilities
    3           max packet size
    n           user name, \0-terminated
    9           scramble_323, \0-terminated

  Packet format (when the server is 4.1 or newer):

    Bytes       Content
    -----       ----
    4           client capabilities
    4           max packet size
    1           charset number
    23          reserved (always 0)
    n           user name, \0-terminated
    n           plugin auth data (e.g. scramble), length encoded
    n           database name, \0-terminated
                (if CLIENT_CONNECT_WITH_DB is set in the capabilities)
    n           client auth plugin name - \0-terminated string,
                (if CLIENT_PLUGIN_AUTH is set in the capabilities)

  @retval 0 ok
  @retval 1 error
*/
static int send_client_reply_packet(MCPVIO_EXT *mpvio,
                                    const uchar *data, int data_len)
{
  MYSQL *mysql= mpvio->mysql;
  NET *net= &mysql->net;
  char *buff, *end;
  size_t buff_size;
  size_t connect_attrs_len=
    (mysql->server_capabilities & CLIENT_CONNECT_ATTRS &&
     mysql->options.extension) ?
    mysql->options.extension->connection_attributes_length : 0;

  DBUG_ASSERT(connect_attrs_len < MAX_CONNECTION_ATTR_STORAGE_LENGTH);


  /*
    Fixed size of the packet is 32 bytes. See mysql_fill_packet_header.
    +9 because data is a length encoded binary where meta data size is max 9.
  */
  buff_size= 33 + USERNAME_LENGTH + data_len + 9 + NAME_LEN + NAME_LEN + connect_attrs_len + 9;
  buff= my_alloca(buff_size);

  /* The client_flags is already calculated. Just fill in the packet header */
  end= mysql_fill_packet_header(mysql, buff, buff_size);

  DBUG_PRINT("info",("Server version = '%s'  capabilites: %lu  status: %u  client_flag: %lu",
		     mysql->server_version, mysql->server_capabilities,
		     mysql->server_status, mysql->client_flag));

  compile_time_assert(MYSQL_USERNAME_LENGTH == USERNAME_LENGTH);

  /* This needs to be changed as it's not useful with big packets */
  if (mysql->user[0])
    strmake(end, mysql->user, USERNAME_LENGTH);
  else
    read_user_name(end);

  /* We have to handle different version of handshake here */
  DBUG_PRINT("info",("user: %s",end));
  end= strend(end) + 1;
  if (data_len)
  {
    /*
      Since the older versions of server do not have
      CLIENT_PLUGIN_AUTH_LENENC_CLIENT_DATA capability,
      a check is performed on this before sending auth data.
      If lenenc support is not available, the data is sent
      in the format of first byte representing the length of
      the string followed by the actual string.
      */
    if (mysql->server_capabilities & CLIENT_PLUGIN_AUTH_LENENC_CLIENT_DATA)
      end= write_length_encoded_string4(end, (char *) (buff + buff_size),
                                       (char *) data,
                                       (char *) (data + data_len));
    else
      end= write_string(end, (char *) (buff + buff_size),
                       (char *) data,
                       (char *) (data + data_len));
    if (end == NULL)
      goto error;
  }
  else
    *end++= 0;

  /* Add database if needed */
  if (mpvio->db && (mysql->server_capabilities & CLIENT_CONNECT_WITH_DB))
  {
    end= strmake(end, mpvio->db, NAME_LEN) + 1;
    mysql->db= my_strdup(key_memory_MYSQL,
                         mpvio->db, MYF(MY_WME));
  }

  if (mysql->server_capabilities & CLIENT_PLUGIN_AUTH)
    end= strmake(end, mpvio->plugin->name, NAME_LEN) + 1;

  end= (char *) send_client_connect_attrs(mysql, (uchar *) end);

  /* Write authentication package */
  MYSQL_TRACE(SEND_AUTH_RESPONSE, mysql, (end-buff, (const unsigned char*)buff));
  if (my_net_write(net, (uchar*) buff, (size_t) (end-buff)) || net_flush(net))
  {
    set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                             ER(CR_SERVER_LOST_EXTENDED),
                             "sending authentication information",
                             errno);
    goto error;
  }
  MYSQL_TRACE(PACKET_SENT, mysql, (end-buff));
  my_afree(buff);
  return 0;
  
error:
  my_afree(buff);
  return 1;
}

/**
  vio->read_packet() callback method for client authentication plugins

  This function is called by a client authentication plugin, when it wants
  to read data from the server.
*/
static int client_mpvio_read_packet(struct st_plugin_vio *mpv, uchar **buf)
{
  MCPVIO_EXT *mpvio= (MCPVIO_EXT*)mpv;
  MYSQL *mysql= mpvio->mysql;
  ulong  pkt_len;

  /* there are cached data left, feed it to a plugin */
  if (mpvio->cached_server_reply.pkt)
  {
    *buf= mpvio->cached_server_reply.pkt;
    mpvio->cached_server_reply.pkt= 0;
    mpvio->packets_read++;
    return mpvio->cached_server_reply.pkt_len;
  }

  if (mpvio->packets_read == 0)
  {
    /*
      the server handshake packet came from the wrong plugin,
      or it's mysql_change_user(). Either way, there is no data
      for a plugin to read. send a dummy packet to the server
      to initiate a dialog.
    */
    if (client_mpvio_write_packet(mpv, 0, 0))
      return (int)packet_error;
  }

  /* otherwise read the data */
  pkt_len= (*mysql->methods->read_change_user_result)(mysql);
  mpvio->last_read_packet_len= pkt_len;
  *buf= mysql->net.read_pos;

  /* was it a request to change plugins ? */
  if (**buf == 254)
    return (int)packet_error; /* if yes, this plugin shan't continue */

  /*
    the server sends \1\255 or \1\254 instead of just \255 or \254 -
    for us to not confuse it with an error or "change plugin" packets.
    We remove this escaping \1 here.

    See also server_mpvio_write_packet() where the escaping is done.
  */
  if (pkt_len && **buf == 1)
  {
    (*buf)++;
    pkt_len--;
  }
  mpvio->packets_read++;
  return pkt_len;
}

/**
  vio->write_packet() callback method for client authentication plugins

  This function is called by a client authentication plugin, when it wants
  to send data to the server.

  It transparently wraps the data into a change user or authentication
  handshake packet, if neccessary.
*/
static int client_mpvio_write_packet(struct st_plugin_vio *mpv,
                                     const uchar *pkt, int pkt_len)
{
  int res;
  MCPVIO_EXT *mpvio= (MCPVIO_EXT*)mpv;

  if (mpvio->packets_written == 0)
  {
    if (mpvio->mysql_change_user)
      res= send_change_user_packet(mpvio, pkt, pkt_len);
    else
      res= send_client_reply_packet(mpvio, pkt, pkt_len);
  }
  else
  {
    NET *net= &mpvio->mysql->net;

    MYSQL_TRACE(SEND_AUTH_DATA, mpvio->mysql, (pkt_len, pkt));

    if (mpvio->mysql->thd)
      res= 1; /* no chit-chat in embedded */
    else
      res= my_net_write(net, pkt, pkt_len) || net_flush(net);

    if (!res)
    {
      MYSQL_TRACE(PACKET_SENT, mpvio->mysql, (pkt_len));
    }
    else
      set_mysql_extended_error(mpvio->mysql, CR_SERVER_LOST, unknown_sqlstate,
                               ER(CR_SERVER_LOST_EXTENDED),
                               "sending authentication information",
                               errno);
  }
  mpvio->packets_written++;
  return res;
}

/**
  fills MYSQL_PLUGIN_VIO_INFO structure with the information about the
  connection
*/
void mpvio_info(Vio *vio, MYSQL_PLUGIN_VIO_INFO *info)
{
  memset(info, 0, sizeof(*info));
  switch (vio->type) {
  case VIO_TYPE_TCPIP:
    info->protocol= MYSQL_VIO_TCP;
    info->socket= (int)vio_fd(vio);
    return;
  case VIO_TYPE_SOCKET:
    info->protocol= MYSQL_VIO_SOCKET;
    info->socket= (int)vio_fd(vio);
    return;
  case VIO_TYPE_SSL:
    {
      struct sockaddr addr;
      socklen_t addrlen= sizeof(addr);
      if (getsockname(vio_fd(vio), &addr, &addrlen))
        return;
      info->protocol= addr.sa_family == AF_UNIX ?
        MYSQL_VIO_SOCKET : MYSQL_VIO_TCP;
      info->socket= (int)vio_fd(vio);
      return;
    }
#ifdef _WIN32
  case VIO_TYPE_NAMEDPIPE:
    info->protocol= MYSQL_VIO_PIPE;
    info->handle= vio->hPipe;
    return;
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
  case VIO_TYPE_SHARED_MEMORY:
    info->protocol= MYSQL_VIO_MEMORY;
    info->handle= vio->handle_file_map; /* or what ? */
    return;
#endif
#endif
  default: DBUG_ASSERT(0);
  }
}

static void client_mpvio_info(MYSQL_PLUGIN_VIO *vio,
                              MYSQL_PLUGIN_VIO_INFO *info)
{
  MCPVIO_EXT *mpvio= (MCPVIO_EXT*)vio;
  mpvio_info(mpvio->mysql->net.vio, info);
}


my_bool libmysql_cleartext_plugin_enabled= 0;

static my_bool check_plugin_enabled(MYSQL *mysql, auth_plugin_t *plugin)
{
  if (plugin == &clear_password_client_plugin &&
      (!libmysql_cleartext_plugin_enabled &&
       (!mysql->options.extension ||
       !mysql->options.extension->enable_cleartext_plugin)))
  {
    set_mysql_extended_error(mysql, CR_AUTH_PLUGIN_CANNOT_LOAD,
                             unknown_sqlstate,
                             ER(CR_AUTH_PLUGIN_CANNOT_LOAD),
                             clear_password_client_plugin.name,
                             "plugin not enabled");
    return TRUE;
  }
  return FALSE;
}


/**
  Client side of the plugin driver authentication.

  @note this is used by both the mysql_real_connect and mysql_change_user

  @param mysql       mysql
  @param data        pointer to the plugin auth data (scramble) in the
                     handshake packet
  @param data_len    the length of the data
  @param data_plugin a plugin that data were prepared for
                     or 0 if it's mysql_change_user()
  @param db          initial db to use, can be 0

  @retval 0 ok
  @retval 1 error
*/
int run_plugin_auth(MYSQL *mysql, char *data, uint data_len,
                    const char *data_plugin, const char *db)
{
  const char    *auth_plugin_name;
  auth_plugin_t *auth_plugin;
  MCPVIO_EXT    mpvio;
  ulong		pkt_length;
  int           res;

  DBUG_ENTER ("run_plugin_auth");
  /* determine the default/initial plugin to use */
  if (mysql->options.extension && mysql->options.extension->default_auth &&
      mysql->server_capabilities & CLIENT_PLUGIN_AUTH)
  {
    auth_plugin_name= mysql->options.extension->default_auth;
    if (!(auth_plugin= (auth_plugin_t*) mysql_client_find_plugin(mysql,
                       auth_plugin_name, MYSQL_CLIENT_AUTHENTICATION_PLUGIN)))
      DBUG_RETURN (1); /* oops, not found */
  }
  else
  {
    auth_plugin= &native_password_client_plugin;
    auth_plugin_name= auth_plugin->name;
  }

  if (check_plugin_enabled(mysql, auth_plugin))
    DBUG_RETURN(1);

  DBUG_PRINT ("info", ("using plugin %s", auth_plugin_name));

  mysql->net.last_errno= 0; /* just in case */

  if (data_plugin && strcmp(data_plugin, auth_plugin_name))
  {
    /* data was prepared for a different plugin, don't show it to this one */
    data= 0;
    data_len= 0;
  }

  mpvio.mysql_change_user= data_plugin == 0;
  mpvio.cached_server_reply.pkt= (uchar*)data;
  mpvio.cached_server_reply.pkt_len= data_len;
  mpvio.read_packet= client_mpvio_read_packet;
  mpvio.write_packet= client_mpvio_write_packet;
  mpvio.info= client_mpvio_info;
  mpvio.mysql= mysql;
  mpvio.packets_read= mpvio.packets_written= 0;
  mpvio.db= db;
  mpvio.plugin= auth_plugin;

  MYSQL_TRACE(AUTH_PLUGIN, mysql, (auth_plugin->name));

  res= auth_plugin->authenticate_user((struct st_plugin_vio *)&mpvio, mysql);
  DBUG_PRINT ("info", ("authenticate_user returned %s", 
                       res == CR_OK ? "CR_OK" : 
                       res == CR_ERROR ? "CR_ERROR" :
                       res == CR_OK_HANDSHAKE_COMPLETE ? 
                         "CR_OK_HANDSHAKE_COMPLETE" : "error"));

  compile_time_assert(CR_OK == -1);
  compile_time_assert(CR_ERROR == 0);

  /*
    The connection may be closed. If so: do not try to read from the buffer.
  */
  if (res > CR_OK && 
      (!my_net_is_inited(&mysql->net) || mysql->net.read_pos[0] != 254))
  {
    /*
      the plugin returned an error. write it down in mysql,
      unless the error code is CR_ERROR and mysql->net.last_errno
      is already set (the plugin has done it)
    */
    DBUG_PRINT ("info", ("res=%d", res));
    if (res > CR_ERROR)
      set_mysql_error(mysql, res, unknown_sqlstate);
    else
      if (!mysql->net.last_errno)
        set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
    DBUG_RETURN (1);
  }

  /* read the OK packet (or use the cached value in mysql->net.read_pos */
  if (res == CR_OK)
    pkt_length= (*mysql->methods->read_change_user_result)(mysql);
  else /* res == CR_OK_HANDSHAKE_COMPLETE */
    pkt_length= mpvio.last_read_packet_len;

  DBUG_PRINT ("info", ("OK packet length=%lu", pkt_length));
  if (pkt_length == packet_error)
  {
    if (mysql->net.last_errno == CR_SERVER_LOST)
      set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                               ER(CR_SERVER_LOST_EXTENDED),
                               "reading authorization packet",
                               errno);
    DBUG_RETURN (1);
  }

  if (mysql->net.read_pos[0] == 254)
  {
    /* The server asked to use a different authentication plugin */
    if (pkt_length < 2)
    {
      set_mysql_error(mysql, CR_MALFORMED_PACKET,
                      unknown_sqlstate);        /* purecov: inspected */
      DBUG_RETURN(1);
    }
    else
    { 
      /* "use different plugin" packet */
      uint len;
      auth_plugin_name= (char*)mysql->net.read_pos + 1;
      len= (uint)strlen(auth_plugin_name); /* safe as my_net_read always appends \0 */
      mpvio.cached_server_reply.pkt_len= pkt_length - len - 2;
      mpvio.cached_server_reply.pkt= mysql->net.read_pos + len + 2;
      DBUG_PRINT ("info", ("change plugin packet from server for plugin %s",
                           auth_plugin_name));
    }

    if (!(auth_plugin= (auth_plugin_t *) mysql_client_find_plugin(mysql,
                         auth_plugin_name, MYSQL_CLIENT_AUTHENTICATION_PLUGIN)))
      DBUG_RETURN (1);

    if (check_plugin_enabled(mysql, auth_plugin))
      DBUG_RETURN(1);

    MYSQL_TRACE(AUTH_PLUGIN, mysql, (auth_plugin->name));

    mpvio.plugin= auth_plugin;
    res= auth_plugin->authenticate_user((struct st_plugin_vio *)&mpvio, mysql);

    DBUG_PRINT ("info", ("second authenticate_user returned %s", 
                         res == CR_OK ? "CR_OK" : 
                         res == CR_ERROR ? "CR_ERROR" :
                         res == CR_OK_HANDSHAKE_COMPLETE ? 
                         "CR_OK_HANDSHAKE_COMPLETE" : "error"));
    if (res > CR_OK)
    {
      if (res > CR_ERROR)
        set_mysql_error(mysql, res, unknown_sqlstate);
      else
        if (!mysql->net.last_errno)
          set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
      DBUG_RETURN (1);
    }

    if (res != CR_OK_HANDSHAKE_COMPLETE)
    {
      /* Read what server thinks about out new auth message report */
      if (cli_safe_read(mysql, NULL) == packet_error)
      {
        if (mysql->net.last_errno == CR_SERVER_LOST)
          set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                                   ER(CR_SERVER_LOST_EXTENDED),
                                   "reading final connect information",
                                   errno);
        DBUG_RETURN (1);
      }
    }
  }
  /*
    net->read_pos[0] should always be 0 here if the server implements
    the protocol correctly
  */
  res= (mysql->net.read_pos[0] != 0);

  MYSQL_TRACE(AUTHENTICATED, mysql, ());
  DBUG_RETURN(res);
}


/** set some default attributes */
static int
set_connect_attributes(MYSQL *mysql, char *buff, size_t buf_len)
{
  int rc= 0;

  /*
    Clean up any values set by the client code. We want these options as
    consistent as possible
  */
  rc+= mysql_options(mysql, MYSQL_OPT_CONNECT_ATTR_DELETE, "_client_name");
  rc+= mysql_options(mysql, MYSQL_OPT_CONNECT_ATTR_DELETE, "_os");
  rc+= mysql_options(mysql, MYSQL_OPT_CONNECT_ATTR_DELETE, "_platform");
  rc+= mysql_options(mysql, MYSQL_OPT_CONNECT_ATTR_DELETE, "_pid");
  rc+= mysql_options(mysql, MYSQL_OPT_CONNECT_ATTR_DELETE, "_thread");
  rc+= mysql_options(mysql, MYSQL_OPT_CONNECT_ATTR_DELETE, "_client_version");

  /*
   Now let's set up some values
  */
  rc+= mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD,
                     "_client_name", "libmysql");
  rc+= mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD,
                      "_client_version", PACKAGE_VERSION);
  rc+= mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD,
                      "_os", SYSTEM_TYPE);
  rc+= mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD,
                      "_platform", MACHINE_TYPE);
#ifdef _WIN32
  my_snprintf(buff, buf_len, "%lu", (ulong) GetCurrentProcessId());
#else
  my_snprintf(buff, buf_len, "%lu", (ulong) getpid());
#endif
  rc+= mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD, "_pid", buff);

#ifdef _WIN32
  my_snprintf(buff, buf_len, "%lu", (ulong) GetCurrentThreadId());
  rc+= mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD, "_thread", buff);
#endif

  return rc > 0 ? 1 : 0;
}


MYSQL * STDCALL 
CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
		       const char *passwd, const char *db,
		       uint port, const char *unix_socket,ulong client_flag)
{
  char		buff[NAME_LEN+USERNAME_LENGTH+100];
  int           scramble_data_len, pkt_scramble_len= 0;
  char          *end,*host_info= 0, *server_version_end, *pkt_end;
  char          *scramble_data;
  const char    *scramble_plugin;
  ulong		pkt_length;
  NET		*net= &mysql->net;
#ifdef _WIN32
  HANDLE	hPipe=INVALID_HANDLE_VALUE;
#endif
#ifdef HAVE_SYS_UN_H
  struct	sockaddr_un UNIXaddr;
#endif
  DBUG_ENTER("mysql_real_connect");

  DBUG_PRINT("enter",("host: %s  db: %s  user: %s (client)",
		      host ? host : "(Null)",
		      db ? db : "(Null)",
		      user ? user : "(Null)"));

  /* Test whether we're already connected */
  if (net->vio)
  {
    set_mysql_error(mysql, CR_ALREADY_CONNECTED, unknown_sqlstate);
    DBUG_RETURN(0);
  }

  if (set_connect_attributes(mysql, buff, sizeof(buff)))
    DBUG_RETURN(0);

  mysql->methods= &client_methods;
  net->vio = 0;				/* If something goes wrong */
  mysql->client_flag=0;			/* For handshake */

  /* use default options */
  if (mysql->options.my_cnf_file || mysql->options.my_cnf_group)
  {
    mysql_read_default_options(&mysql->options,
			       (mysql->options.my_cnf_file ?
				mysql->options.my_cnf_file : "my"),
			       mysql->options.my_cnf_group);
    my_free(mysql->options.my_cnf_file);
    my_free(mysql->options.my_cnf_group);
    mysql->options.my_cnf_file=mysql->options.my_cnf_group=0;
  }

  /* Some empty-string-tests are done because of ODBC */
  if (!host || !host[0])
    host=mysql->options.host;
  if (!user || !user[0])
  {
    user=mysql->options.user;
    if (!user)
      user= "";
  }
  if (!passwd)
  {
    passwd=mysql->options.password;
#if !defined(MYSQL_SERVER)
    if (!passwd)
      passwd=getenv("MYSQL_PWD");		/* get it from environment */
#endif
    if (!passwd)
      passwd= "";
  }
  if (!db || !db[0])
    db=mysql->options.db;
  if (!port)
    port=mysql->options.port;
  if (!unix_socket)
    unix_socket=mysql->options.unix_socket;

  mysql->server_status=SERVER_STATUS_AUTOCOMMIT;
  DBUG_PRINT("info", ("Connecting"));

  MYSQL_TRACE_STAGE(mysql, CONNECTING);
  MYSQL_TRACE(CONNECTING, mysql, ());

  /*
    Part 0: Grab a socket and connect it to the server
  */
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
  if ((!mysql->options.protocol ||
       mysql->options.protocol == MYSQL_PROTOCOL_MEMORY) &&
      (!host || !strcmp(host,LOCAL_HOST)))
  {
    HANDLE handle_map;
    DBUG_PRINT("info", ("Using shared memory"));

    handle_map= create_shared_memory(mysql, net,
                                     get_win32_connect_timeout(mysql));

    if (handle_map == INVALID_HANDLE_VALUE)
    {
      DBUG_PRINT("error",
		 ("host: '%s'  socket: '%s'  shared memory: %s  have_tcpip: %d",
		  host ? host : "<null>",
		  unix_socket ? unix_socket : "<null>",
		  (int) mysql->options.shared_memory_base_name,
		  (int) have_tcpip));
      if (mysql->options.protocol == MYSQL_PROTOCOL_MEMORY)
	goto error;

      /*
        Try also with PIPE or TCP/IP. Clear the error from
        create_shared_memory().
      */

      net_clear_error(net);
    }
    else
    {
      mysql->options.protocol=MYSQL_PROTOCOL_MEMORY;
      unix_socket = 0;
      host=mysql->options.shared_memory_base_name;
      my_snprintf(host_info=buff, sizeof(buff)-1,
                  ER(CR_SHARED_MEMORY_CONNECTION), host);
    }
  }
#endif /* _WIN32 && !EMBEDDED_LIBRARY */
#if defined(HAVE_SYS_UN_H)
  if (!net->vio &&
      (!mysql->options.protocol ||
       mysql->options.protocol == MYSQL_PROTOCOL_SOCKET) &&
      (unix_socket || mysql_unix_port) &&
      (!host || !strcmp(host,LOCAL_HOST)))
  {
    my_socket sock= socket(AF_UNIX, SOCK_STREAM, 0);
    DBUG_PRINT("info", ("Using socket"));
    if (sock == SOCKET_ERROR)
    {
      set_mysql_extended_error(mysql, CR_SOCKET_CREATE_ERROR,
                               unknown_sqlstate,
                               ER(CR_SOCKET_CREATE_ERROR),
                               socket_errno);
      goto error;
    }

    net->vio= vio_new(sock, VIO_TYPE_SOCKET,
                      VIO_LOCALHOST | VIO_BUFFERED_READ);
    if (!net->vio)
    {
      DBUG_PRINT("error",("Unknow protocol %d ", mysql->options.protocol));
      set_mysql_error(mysql, CR_CONN_UNKNOW_PROTOCOL, unknown_sqlstate);
      closesocket(sock);
      goto error;
    }

    host= LOCAL_HOST;
    if (!unix_socket)
      unix_socket= mysql_unix_port;
    host_info= (char*) ER(CR_LOCALHOST_CONNECTION);
    DBUG_PRINT("info", ("Using UNIX sock '%s'", unix_socket));

    memset(&UNIXaddr, 0, sizeof(UNIXaddr));
    UNIXaddr.sun_family= AF_UNIX;
    strmake(UNIXaddr.sun_path, unix_socket, sizeof(UNIXaddr.sun_path)-1);

    if (vio_socket_connect(net->vio, (struct sockaddr *) &UNIXaddr,
                           sizeof(UNIXaddr), get_vio_connect_timeout(mysql)))
    {
      DBUG_PRINT("error",("Got error %d on connect to local server",
			  socket_errno));
      set_mysql_extended_error(mysql, CR_CONNECTION_ERROR,
                               unknown_sqlstate,
                               ER(CR_CONNECTION_ERROR),
                               unix_socket, socket_errno);
      vio_delete(net->vio);
      net->vio= 0;
      goto error;
    }
    mysql->options.protocol=MYSQL_PROTOCOL_SOCKET;
  }
#elif defined(_WIN32)
  if (!net->vio &&
      (mysql->options.protocol == MYSQL_PROTOCOL_PIPE ||
       (host && !strcmp(host,LOCAL_HOST_NAMEDPIPE)) ||
       (! have_tcpip && (unix_socket || !host && is_NT()))))
  {
    hPipe= create_named_pipe(mysql, get_win32_connect_timeout(mysql),
                             &host, &unix_socket);

    if (hPipe == INVALID_HANDLE_VALUE)
    {
      DBUG_PRINT("error",
		 ("host: '%s'  socket: '%s'  have_tcpip: %d",
		  host ? host : "<null>",
		  unix_socket ? unix_socket : "<null>",
		  (int) have_tcpip));
      if (mysql->options.protocol == MYSQL_PROTOCOL_PIPE ||
	  (host && !strcmp(host,LOCAL_HOST_NAMEDPIPE)) ||
	  (unix_socket && !strcmp(unix_socket,MYSQL_NAMEDPIPE)))
	goto error;
      /* Try also with TCP/IP */
    }
    else
    {
      net->vio= vio_new_win32pipe(hPipe);
      my_snprintf(host_info=buff, sizeof(buff)-1,
                  ER(CR_NAMEDPIPE_CONNECTION), unix_socket);
    }
  }
#endif
  DBUG_PRINT("info", ("net->vio: %p  protocol: %d",
                      net->vio, mysql->options.protocol));
  if (!net->vio &&
      (!mysql->options.protocol ||
       mysql->options.protocol == MYSQL_PROTOCOL_TCP))
  {
    struct addrinfo *res_lst, *client_bind_ai_lst= NULL, hints, *t_res;
    char port_buf[NI_MAXSERV];
    my_socket sock= SOCKET_ERROR;
    int gai_errno, saved_error= 0, status= -1, bind_result= 0;
    uint flags= VIO_BUFFERED_READ;

    unix_socket=0;				/* This is not used */

    if (!port)
      port= mysql_port;

    if (!host)
      host= LOCAL_HOST;

    my_snprintf(host_info=buff, sizeof(buff)-1, ER(CR_TCP_CONNECTION), host);
    DBUG_PRINT("info",("Server name: '%s'.  TCP sock: %d", host, port));

    memset(&hints, 0, sizeof(hints));
    hints.ai_socktype= SOCK_STREAM;
    hints.ai_protocol= IPPROTO_TCP;
    hints.ai_family= AF_UNSPEC;

    DBUG_PRINT("info",("IPV6 getaddrinfo %s", host));
    my_snprintf(port_buf, NI_MAXSERV, "%d", port);
    gai_errno= getaddrinfo(host, port_buf, &hints, &res_lst);

    if (gai_errno != 0) 
    { 
      /* 
        For DBUG we are keeping the right message but for client we default to
        historical error message.
      */
      DBUG_PRINT("info",("IPV6 getaddrinfo error %d", gai_errno));
      set_mysql_extended_error(mysql, CR_UNKNOWN_HOST, unknown_sqlstate,
                               ER(CR_UNKNOWN_HOST), host, errno);

      goto error;
    }

    /* Get address info for client bind name if it is provided */
    if (mysql->options.ci.bind_address)
    {
      int bind_gai_errno= 0;

      DBUG_PRINT("info",("Resolving addresses for client bind: '%s'",
                         mysql->options.ci.bind_address));
      /* Lookup address info for name */
      bind_gai_errno= getaddrinfo(mysql->options.ci.bind_address, 0,
                                  &hints, &client_bind_ai_lst);
      if (bind_gai_errno)
      {
        DBUG_PRINT("info",("client bind getaddrinfo error %d", bind_gai_errno));
        set_mysql_extended_error(mysql, CR_UNKNOWN_HOST, unknown_sqlstate,
                                 ER(CR_UNKNOWN_HOST),
                                 mysql->options.ci.bind_address,
                                 bind_gai_errno);

        freeaddrinfo(res_lst);
        goto error;
      }
      DBUG_PRINT("info", ("  got address info for client bind name"));
    }

    /*
      A hostname might map to multiple IP addresses (IPv4/IPv6). Go over the
      list of IP addresses until a successful connection can be established.
      For each IP address, attempt to bind the socket to each client address
      for the client-side bind hostname until the bind is successful.
    */
    DBUG_PRINT("info", ("Try connect on all addresses for host."));
    for (t_res= res_lst; t_res; t_res= t_res->ai_next)
    {
      DBUG_PRINT("info", ("Create socket, family: %d  type: %d  proto: %d",
                          t_res->ai_family, t_res->ai_socktype,
                          t_res->ai_protocol));

      sock= socket(t_res->ai_family, t_res->ai_socktype, t_res->ai_protocol);
      if (sock == SOCKET_ERROR)
      {
        DBUG_PRINT("info", ("Socket created was invalid"));
        /* Try next address if there is one */
        saved_error= socket_errno;
        continue;
      }

      if (client_bind_ai_lst)
      {
        struct addrinfo* curr_bind_ai= NULL;
        DBUG_PRINT("info", ("Attempting to bind socket to bind address(es)"));

        /*
           We'll attempt to bind to each of the addresses returned, until
           we find one that works.
           If none works, we'll try the next destination host address
           (if any)
        */
        curr_bind_ai= client_bind_ai_lst;

        while (curr_bind_ai != NULL)
        {
          /* Attempt to bind the socket to the given address */
          bind_result= bind(sock,
                            curr_bind_ai->ai_addr,
                            curr_bind_ai->ai_addrlen);
          if (!bind_result)
            break;   /* Success */

          DBUG_PRINT("info", ("bind failed, attempting another bind address"));
          /* Problem with the bind, move to next address if present */
          curr_bind_ai= curr_bind_ai->ai_next;
        }

        if (bind_result)
        {
          /*
            Could not bind to any client-side address with this destination
             Try the next destination address (if any)
          */
          DBUG_PRINT("info", ("All bind attempts with this address failed"));
          saved_error= socket_errno;
          closesocket(sock);
          continue;
        }
        DBUG_PRINT("info", ("Successfully bound client side of socket"));
      }

      /* Create a new Vio object to abstract the socket. */
      if (!net->vio)
      {
        if (!(net->vio= vio_new(sock, VIO_TYPE_TCPIP, flags)))
        {
          set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
          closesocket(sock);
          freeaddrinfo(res_lst);
          if (client_bind_ai_lst)
            freeaddrinfo(client_bind_ai_lst);
          goto error;
        }
      }
      /* Just reinitialize if one is already allocated. */
      else if (vio_reset(net->vio, VIO_TYPE_TCPIP, sock, NULL, flags))
      {
        set_mysql_error(mysql, CR_UNKNOWN_ERROR, unknown_sqlstate);
        closesocket(sock);
        freeaddrinfo(res_lst);
        if (client_bind_ai_lst)
          freeaddrinfo(client_bind_ai_lst);
        goto error;
      }

      DBUG_PRINT("info", ("Connect socket"));
      status= vio_socket_connect(net->vio, t_res->ai_addr,
                                 (socklen_t)t_res->ai_addrlen,
                                 get_vio_connect_timeout(mysql));
      /*
        Here we rely on vio_socket_connect() to return success only if
        the connect attempt was really successful. Otherwise we would
        stop trying another address, believing we were successful.
      */
      if (!status)
        break;

      /*
        Save either the socket error status or the error code of
        the failed vio_connection operation. It is necessary to
        avoid having it overwritten by later operations.
      */
      saved_error= socket_errno;

      DBUG_PRINT("info", ("No success, try next address."));
    }
    DBUG_PRINT("info",
               ("End of connect attempts, sock: %d  status: %d  error: %d",
                sock, status, saved_error));

    freeaddrinfo(res_lst);
    if (client_bind_ai_lst)
      freeaddrinfo(client_bind_ai_lst);

    if (sock == SOCKET_ERROR)
    {
      set_mysql_extended_error(mysql, CR_IPSOCK_ERROR, unknown_sqlstate,
                                ER(CR_IPSOCK_ERROR), saved_error);
      goto error;
    }

    if (status)
    {
      DBUG_PRINT("error",("Got error %d on connect to '%s'", saved_error, host));
      set_mysql_extended_error(mysql, CR_CONN_HOST_ERROR, unknown_sqlstate,
                                ER(CR_CONN_HOST_ERROR), host, saved_error);
      goto error;
    }
  }

  DBUG_PRINT("info", ("net->vio: %p", net->vio));
  if (!net->vio)
  {
    DBUG_PRINT("error",("Unknow protocol %d ",mysql->options.protocol));
    set_mysql_error(mysql, CR_CONN_UNKNOW_PROTOCOL, unknown_sqlstate);
    goto error;
  }

  if (my_net_init(net, net->vio))
  {
    vio_delete(net->vio);
    net->vio = 0;
    set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
    goto error;
  }
  vio_keepalive(net->vio,TRUE);

  /* If user set read_timeout, let it override the default */
  if (mysql->options.read_timeout)
    my_net_set_read_timeout(net, mysql->options.read_timeout);

  /* If user set write_timeout, let it override the default */
  if (mysql->options.write_timeout)
    my_net_set_write_timeout(net, mysql->options.write_timeout);

  if (mysql->options.max_allowed_packet)
    net->max_packet_size= mysql->options.max_allowed_packet;

  MYSQL_TRACE(CONNECTED, mysql, ());
  MYSQL_TRACE_STAGE(mysql, WAIT_FOR_INIT_PACKET);

  /* Get version info */
  mysql->protocol_version= PROTOCOL_VERSION;	/* Assume this */
  if (mysql->options.connect_timeout &&
      (vio_io_wait(net->vio, VIO_IO_EVENT_READ,
                   get_vio_connect_timeout(mysql)) < 1))
  {
    set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                             ER(CR_SERVER_LOST_EXTENDED),
                             "waiting for initial communication packet",
                             socket_errno);
    goto error;
  }

  /*
    Part 1: Connection established, read and parse first packet
  */
  DBUG_PRINT("info", ("Read first packet."));

  if ((pkt_length=cli_safe_read(mysql, NULL)) == packet_error)
  {
    if (mysql->net.last_errno == CR_SERVER_LOST)
      set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                               ER(CR_SERVER_LOST_EXTENDED),
                               "reading initial communication packet",
                               socket_errno);
    goto error;
  }
  pkt_end= (char*)net->read_pos + pkt_length;
  /* Check if version of protocol matches current one */
  mysql->protocol_version= net->read_pos[0];
  DBUG_DUMP("packet",(uchar*) net->read_pos,10);
  DBUG_PRINT("info",("mysql protocol version %d, server=%d",
		     PROTOCOL_VERSION, mysql->protocol_version));
  if (mysql->protocol_version != PROTOCOL_VERSION)
  {
    set_mysql_extended_error(mysql, CR_VERSION_ERROR, unknown_sqlstate,
                             ER(CR_VERSION_ERROR), mysql->protocol_version,
                             PROTOCOL_VERSION);
    goto error;
  }
  server_version_end= end= strend((char*) net->read_pos+1);
  mysql->thread_id=uint4korr((uchar*) end + 1);
  end+=5;
  /* 
    Scramble is split into two parts because old clients do not understand
    long scrambles; here goes the first part.
  */
  scramble_data= end;
  scramble_data_len= AUTH_PLUGIN_DATA_PART_1_LENGTH + 1;
  scramble_plugin= NULL;
  end+= scramble_data_len;

  if (pkt_end >= end + 1)
    mysql->server_capabilities=uint2korr((uchar*) end);
  if (pkt_end >= end + 18)
  {
    /* New protocol with 16 bytes to describe server characteristics */
    mysql->server_language=end[2];
    mysql->server_status=uint2korr((uchar*) end + 3);
    mysql->server_capabilities|= uint2korr((uchar*) end + 5) << 16;
    pkt_scramble_len= end[7];
    if (pkt_scramble_len < 0)
    {
      set_mysql_error(mysql, CR_MALFORMED_PACKET,
                      unknown_sqlstate);        /* purecov: inspected */
      goto error;
    }
  }
  end+= 18;

  if (mysql_init_character_set(mysql))
    goto error;

  /* Save connection information */
  if (!my_multi_malloc(key_memory_MYSQL,
                       MYF(0),
		       &mysql->host_info, (uint) strlen(host_info)+1,
		       &mysql->host,      (uint) strlen(host)+1,
		       &mysql->unix_socket,unix_socket ?
		       (uint) strlen(unix_socket)+1 : (uint) 1,
		       &mysql->server_version,
		       (uint) (server_version_end - (char*) net->read_pos + 1),
		       NullS) ||
      !(mysql->user=my_strdup(key_memory_MYSQL,
                              user,MYF(0))) ||
      !(mysql->passwd=my_strdup(key_memory_MYSQL,
                                passwd,MYF(0))))
  {
    set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
    goto error;
  }
  my_stpcpy(mysql->host_info,host_info);
  my_stpcpy(mysql->host,host);
  if (unix_socket)
    my_stpcpy(mysql->unix_socket,unix_socket);
  else
    mysql->unix_socket=0;
  my_stpcpy(mysql->server_version,(char*) net->read_pos+1);
  mysql->port=port;

  if (pkt_end >= end + SCRAMBLE_LENGTH - AUTH_PLUGIN_DATA_PART_1_LENGTH + 1)
  {
    /*
     move the first scramble part - directly in the NET buffer -
     to get a full continuous scramble. We've read all the header,
     and can overwrite it now.
    */
    memmove(end - AUTH_PLUGIN_DATA_PART_1_LENGTH, scramble_data,
            AUTH_PLUGIN_DATA_PART_1_LENGTH);
    scramble_data= end - AUTH_PLUGIN_DATA_PART_1_LENGTH;
    if (mysql->server_capabilities & CLIENT_PLUGIN_AUTH)
    {
      scramble_data_len= pkt_scramble_len;
      scramble_plugin= scramble_data + scramble_data_len;
      if (scramble_data + scramble_data_len > pkt_end)
        scramble_data_len= (int)(pkt_end - scramble_data);
    }
    else
    {
      scramble_data_len= (int)(pkt_end - scramble_data);
      scramble_plugin= native_password_plugin_name;
    }
  }
  else
  {
    set_mysql_error(mysql, CR_MALFORMED_PACKET, unknown_sqlstate);
    goto error;
  }

  MYSQL_TRACE(INIT_PACKET_RECEIVED, mysql, (pkt_length, net->read_pos));
  MYSQL_TRACE_STAGE(mysql, AUTHENTICATE);

  /* try and bring up SSL if possible */
  cli_calculate_client_flag(mysql, db, client_flag);
  if (cli_establish_ssl(mysql))
    goto error;

  /*
    Part 2: invoke the plugin to send the authentication data to the server
  */

  if (run_plugin_auth(mysql, scramble_data, scramble_data_len,
                      scramble_plugin, db))
    goto error;

  MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);

  /*
    Part 3: authenticated, finish the initialization of the connection
  */

  if (mysql->client_flag & CLIENT_COMPRESS)      /* We will use compression */
    net->compress=1;

#ifdef CHECK_LICENSE 
  if (check_license(mysql))
    goto error;
#endif

  if (db && !mysql->db && mysql_select_db(mysql, db))
  {
    if (mysql->net.last_errno == CR_SERVER_LOST)
        set_mysql_extended_error(mysql, CR_SERVER_LOST, unknown_sqlstate,
                                 ER(CR_SERVER_LOST_EXTENDED),
                                 "Setting intital database",
                                 errno);
    goto error;
  }

  /*
     Using init_commands is not supported when connecting from within the
     server.
  */
#ifndef MYSQL_SERVER
  if (mysql->options.init_commands)
  {
    DYNAMIC_ARRAY *init_commands= mysql->options.init_commands;
    char **ptr= (char**)init_commands->buffer;
    char **end_command= ptr + init_commands->elements;

    my_bool reconnect=mysql->reconnect;
    mysql->reconnect=0;

    for (; ptr < end_command; ptr++)
    {
      int status;

      if (mysql_real_query(mysql,*ptr, (ulong) strlen(*ptr)))
	goto error;

      do {
        if (mysql->fields)
        {
          MYSQL_RES *res;
          if (!(res= cli_use_result(mysql)))
            goto error;
          mysql_free_result(res);
        }
        if ((status= mysql_next_result(mysql)) > 0)
          goto error;
      } while (status == 0);
    }
    mysql->reconnect=reconnect;
  }
#endif

  DBUG_PRINT("exit", ("Mysql handler: 0x%lx", (long) mysql));
  DBUG_RETURN(mysql);

error:
  DBUG_PRINT("error",("message: %u/%s (%s)",
                      net->last_errno,
                      net->sqlstate,
                      net->last_error));
  {
    /* Free alloced memory */
    end_server(mysql);
    mysql_close_free(mysql);
    if (!(client_flag & CLIENT_REMEMBER_OPTIONS))
      mysql_close_free_options(mysql);
  }
  DBUG_RETURN(0);
}


my_bool mysql_reconnect(MYSQL *mysql)
{
  MYSQL tmp_mysql;
  DBUG_ENTER("mysql_reconnect");
  DBUG_ASSERT(mysql);
  DBUG_PRINT("enter", ("mysql->reconnect: %d", mysql->reconnect));

  if (!mysql->reconnect ||
      (mysql->server_status & SERVER_STATUS_IN_TRANS) || !mysql->host_info)
  {
    /* Allow reconnect next time */
    mysql->server_status&= ~SERVER_STATUS_IN_TRANS;
    set_mysql_error(mysql, CR_SERVER_GONE_ERROR, unknown_sqlstate);
    DBUG_RETURN(1);
  }
  mysql_init(&tmp_mysql);
  tmp_mysql.options= mysql->options;
  tmp_mysql.options.my_cnf_file= tmp_mysql.options.my_cnf_group= 0;

  if (!mysql_real_connect(&tmp_mysql,mysql->host,mysql->user,mysql->passwd,
			  mysql->db, mysql->port, mysql->unix_socket,
			  mysql->client_flag | CLIENT_REMEMBER_OPTIONS))
  {
    memset(&tmp_mysql.options, 0, sizeof(tmp_mysql.options));
    mysql_close(&tmp_mysql);
    mysql->net.last_errno= tmp_mysql.net.last_errno;
    my_stpcpy(mysql->net.last_error, tmp_mysql.net.last_error);
    my_stpcpy(mysql->net.sqlstate, tmp_mysql.net.sqlstate);
    DBUG_RETURN(1);
  }
  if (mysql_set_character_set(&tmp_mysql, mysql->charset->csname))
  {
    DBUG_PRINT("error", ("mysql_set_character_set() failed"));
    memset(&tmp_mysql.options, 0, sizeof(tmp_mysql.options));
    mysql_close(&tmp_mysql);
    mysql->net.last_errno= tmp_mysql.net.last_errno;
    my_stpcpy(mysql->net.last_error, tmp_mysql.net.last_error);
    my_stpcpy(mysql->net.sqlstate, tmp_mysql.net.sqlstate);
    DBUG_RETURN(1);
  }

  DBUG_PRINT("info", ("reconnect succeded"));
  tmp_mysql.reconnect= 1;
  tmp_mysql.free_me= mysql->free_me;

  /* Move prepared statements (if any) over to the new mysql object */
  tmp_mysql.stmts= mysql->stmts;
  mysql->stmts= 0;

  /* Don't free options as these are now used in tmp_mysql */
  memset(&mysql->options, 0, sizeof(mysql->options));
  mysql->free_me=0;
  mysql_close(mysql);
  *mysql=tmp_mysql;
  net_clear(&mysql->net, 1);
  mysql->affected_rows= ~(my_ulonglong) 0;
  DBUG_RETURN(0);
}


/**************************************************************************
  Set current database
**************************************************************************/

int STDCALL
mysql_select_db(MYSQL *mysql, const char *db)
{
  int error;
  DBUG_ENTER("mysql_select_db");
  DBUG_PRINT("enter",("db: '%s'",db));

  if ((error=simple_command(mysql,COM_INIT_DB, (const uchar*) db,
                            (ulong) strlen(db),0)))
    DBUG_RETURN(error);
  my_free(mysql->db);
  mysql->db=my_strdup(key_memory_MYSQL,
                      db,MYF(MY_WME));
  DBUG_RETURN(0);
}


/*************************************************************************
  Send a QUIT to the server and close the connection
  If handle is alloced by mysql connect free it.
*************************************************************************/

void mysql_close_free_options(MYSQL *mysql)
{
  DBUG_ENTER("mysql_close_free_options");

  my_free(mysql->options.user);
  my_free(mysql->options.host);
  my_free(mysql->options.password);
  my_free(mysql->options.unix_socket);
  my_free(mysql->options.db);
  my_free(mysql->options.my_cnf_file);
  my_free(mysql->options.my_cnf_group);
  my_free(mysql->options.charset_dir);
  my_free(mysql->options.charset_name);
  my_free(mysql->options.ci.client_ip);
  /* ci.bind_adress is union with client_ip, already freed above */
  if (mysql->options.init_commands)
  {
    DYNAMIC_ARRAY *init_commands= mysql->options.init_commands;
    char **ptr= (char**)init_commands->buffer;
    char **end= ptr + init_commands->elements;
    for (; ptr<end; ptr++)
      my_free(*ptr);
    delete_dynamic(init_commands);
    my_free(init_commands);
  }
#if defined(HAVE_OPENSSL) && !defined(EMBEDDED_LIBRARY)
  mysql_ssl_free(mysql);
#endif /* HAVE_OPENSSL && !EMBEDDED_LIBRARY */
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
  if (mysql->options.shared_memory_base_name != def_shared_memory_base_name)
    my_free(mysql->options.shared_memory_base_name);
#endif /* _WIN32 && !EMBEDDED_LIBRARY */
  if (mysql->options.extension)
  {
    my_free(mysql->options.extension->plugin_dir);
    my_free(mysql->options.extension->default_auth);
    my_free(mysql->options.extension->server_public_key_path);
    my_hash_free(&mysql->options.extension->connection_attributes);
    my_free(mysql->options.extension);
  }
  memset(&mysql->options, 0, sizeof(mysql->options));
  DBUG_VOID_RETURN;
}


/*
  Free all memory allocated in a MYSQL handle but preserve
  current options if any.
*/

void mysql_close_free(MYSQL *mysql)
{
  my_free(mysql->host_info);
  my_free(mysql->user);
  my_free(mysql->passwd);
  my_free(mysql->db);

  /* Free extension if any */
  if (mysql->extension)
    mysql_extension_free(mysql->extension);

#if defined(EMBEDDED_LIBRARY) || MYSQL_VERSION_ID >= 50100
  my_free(mysql->info_buffer);
  mysql->info_buffer= 0;
#endif
  /* Clear pointers for better safety */
  mysql->host_info= NULL;
  mysql->user= NULL;
  mysql->passwd= NULL;
  mysql->db= NULL;
  mysql->extension= NULL;
}


/**
  For use when the connection to the server has been lost (in which case 
  the server has discarded all information about prepared statements
  associated with the connection).

  Mark all statements in mysql->stmts by setting stmt->mysql= 0 if the
  statement has transitioned beyond the MYSQL_STMT_INIT_DONE state, and
  unlink the statement from the mysql->stmts list.

  The remaining pruned list of statements (if any) is kept in mysql->stmts.

  @param mysql       pointer to the MYSQL object

  @return none
*/
static void mysql_prune_stmt_list(MYSQL *mysql)
{
  LIST *pruned_list= NULL;

  while(mysql->stmts)
  {
    LIST *element= mysql->stmts;
    MYSQL_STMT *stmt;

    mysql->stmts= list_delete(element, element);
    stmt= (MYSQL_STMT *) element->data;
    if (stmt->state != MYSQL_STMT_INIT_DONE)
    {
      stmt->mysql= 0;
      stmt->last_errno= CR_SERVER_LOST;
      my_stpcpy(stmt->last_error, ER(CR_SERVER_LOST));
      my_stpcpy(stmt->sqlstate, unknown_sqlstate);
    }
    else
    {
      pruned_list= list_add(pruned_list, element);
    }
  }

  mysql->stmts= pruned_list;
}


/*
  Clear connection pointer of every statement: this is necessary
  to give error on attempt to use a prepared statement of closed
  connection.

  SYNOPSYS
    mysql_detach_stmt_list()
      stmt_list  pointer to mysql->stmts
      func_name  name of calling function

  NOTE
    There is similar code in mysql_reconnect(), so changes here
    should also be reflected there.
*/

void mysql_detach_stmt_list(LIST **stmt_list __attribute__((unused)),
                            const char *func_name __attribute__((unused)))
{
#ifdef MYSQL_CLIENT
  /* Reset connection handle in all prepared statements. */
  LIST *element= *stmt_list;
  char buff[MYSQL_ERRMSG_SIZE];
  DBUG_ENTER("mysql_detach_stmt_list");

  my_snprintf(buff, sizeof(buff)-1, ER(CR_STMT_CLOSED), func_name);
  for (; element; element= element->next)
  {
    MYSQL_STMT *stmt= (MYSQL_STMT *) element->data;
    set_stmt_error(stmt, CR_STMT_CLOSED, unknown_sqlstate, buff);
    stmt->mysql= 0;
    /* No need to call list_delete for statement here */
  }
  *stmt_list= 0;
  DBUG_VOID_RETURN;
#endif /* MYSQL_CLIENT */
}


void STDCALL mysql_close(MYSQL *mysql)
{
  DBUG_ENTER("mysql_close");
  if (mysql)					/* Some simple safety */
  {
    /* If connection is still up, send a QUIT message */
    if (mysql->net.vio != 0)
    {
      free_old_query(mysql);
      mysql->status=MYSQL_STATUS_READY; /* Force command */
      mysql->reconnect=0;
      simple_command(mysql,COM_QUIT,(uchar*) 0,0,1);
      end_server(mysql);			/* Sets mysql->net.vio= 0 */
    }
    mysql_close_free_options(mysql);
    mysql_close_free(mysql);
    mysql_detach_stmt_list(&mysql->stmts, "mysql_close");
#ifndef MYSQL_SERVER
    if (mysql->thd)
      (*mysql->methods->free_embedded_thd)(mysql);
#endif
    if (mysql->free_me)
      my_free(mysql);
  }
  DBUG_VOID_RETURN;
}


static my_bool cli_read_query_result(MYSQL *mysql)
{
  uchar *pos;
  ulong field_count;
  ulong length;
  DBUG_ENTER("cli_read_query_result");

  if ((length = cli_safe_read(mysql, NULL)) == packet_error)
    DBUG_RETURN(1);
  free_old_query(mysql);		/* Free old result */
#ifdef MYSQL_CLIENT			/* Avoid warn of unused labels*/
get_info:
#endif
  pos=(uchar*) mysql->net.read_pos;
  if ((field_count= net_field_length(&pos)) == 0)
  {
    read_ok_ex(mysql, length);
#if defined(CLIENT_PROTOCOL_TRACING)
    if (mysql->server_status & SERVER_MORE_RESULTS_EXISTS)
      MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT);
    else
      MYSQL_TRACE_STAGE(mysql, READY_FOR_COMMAND);
#endif
    DBUG_RETURN(0);
  }
#ifdef MYSQL_CLIENT
  if (field_count == NULL_LENGTH)		/* LOAD DATA LOCAL INFILE */
  {
    int error;

    MYSQL_TRACE_STAGE(mysql, FILE_REQUEST);

    if (!(mysql->options.client_flag & CLIENT_LOCAL_FILES))
    {
      set_mysql_error(mysql, CR_MALFORMED_PACKET, unknown_sqlstate);
      DBUG_RETURN(1);
    }   

    error= handle_local_infile(mysql,(char*) pos);

    MYSQL_TRACE_STAGE(mysql, WAIT_FOR_RESULT);

    if ((length= cli_safe_read(mysql, NULL)) == packet_error || error)
      DBUG_RETURN(1);
    goto get_info;				/* Get info packet */
  }
#endif
  if (!(mysql->server_status & SERVER_STATUS_AUTOCOMMIT))
    mysql->server_status|= SERVER_STATUS_IN_TRANS;

  MYSQL_TRACE_STAGE(mysql, WAIT_FOR_FIELD_DEF);

  if (!(mysql->fields=cli_read_metadata(mysql, field_count, protocol_41(mysql) ? 7:5)))
    DBUG_RETURN(1);
  mysql->status= MYSQL_STATUS_GET_RESULT;
  mysql->field_count= (uint) field_count;

  MYSQL_TRACE_STAGE(mysql, WAIT_FOR_ROW);

  DBUG_PRINT("exit",("ok"));
  DBUG_RETURN(0);
}


/*
  Send the query and return so we can do something else.
  Needs to be followed by mysql_read_query_result() when we want to
  finish processing it.
*/

int STDCALL
mysql_send_query(MYSQL* mysql, const char* query, ulong length)
{
  STATE_INFO *info;

  DBUG_ENTER("mysql_send_query");

  if ((info= STATE_DATA(mysql)))
    free_state_change_info(mysql->extension);

  DBUG_RETURN(simple_command(mysql, COM_QUERY, (uchar*) query, length, 1));
}


int STDCALL
mysql_real_query(MYSQL *mysql, const char *query, ulong length)
{
  int retval;
  DBUG_ENTER("mysql_real_query");
  DBUG_PRINT("enter",("handle: %p", mysql));
  DBUG_PRINT("query",("Query = '%-.*s'", (int) length, query));

  if (mysql_send_query(mysql,query,length))
    DBUG_RETURN(1);
  retval= (int) (*mysql->methods->read_query_result)(mysql);
  DBUG_RETURN(retval);
}


/**************************************************************************
  Alloc result struct for buffered results. All rows are read to buffer.
  mysql_data_seek may be used.
**************************************************************************/

MYSQL_RES * STDCALL mysql_store_result(MYSQL *mysql)
{
  MYSQL_RES *result;
  DBUG_ENTER("mysql_store_result");

  if (!mysql->fields)
    DBUG_RETURN(0);
  if (mysql->status != MYSQL_STATUS_GET_RESULT)
  {
    set_mysql_error(mysql, CR_COMMANDS_OUT_OF_SYNC, unknown_sqlstate);
    DBUG_RETURN(0);
  }
  mysql->status=MYSQL_STATUS_READY;		/* server is ready */
  if (!(result=(MYSQL_RES*) my_malloc(key_memory_MYSQL_RES,
                                      (uint) (sizeof(MYSQL_RES)+
					      sizeof(ulong) *
					      mysql->field_count),
				      MYF(MY_WME | MY_ZEROFILL))))
  {
    set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
    DBUG_RETURN(0);
  }
  result->methods= mysql->methods;
  result->eof=1;				/* Marker for buffered */
  result->lengths=(ulong*) (result+1);
  if (!(result->data=
	(*mysql->methods->read_rows)(mysql,mysql->fields,mysql->field_count)))
  {
    my_free(result);
    DBUG_RETURN(0);
  }
  mysql->affected_rows= result->row_count= result->data->rows;
  result->data_cursor=	result->data->data;
  result->fields=	mysql->fields;
  result->field_alloc= mysql->field_alloc;
  result->field_count=	mysql->field_count;
  /* The rest of result members is zerofilled in my_malloc */
  mysql->fields=0;				/* fields is now in result */
  clear_alloc_root(&mysql->field_alloc);
  /* just in case this was mistakenly called after mysql_stmt_execute() */
  mysql->unbuffered_fetch_owner= 0;
  DBUG_RETURN(result);				/* Data fetched */
}


/**************************************************************************
  Alloc struct for use with unbuffered reads. Data is fetched by domand
  when calling to mysql_fetch_row.
  mysql_data_seek is a noop.

  No other queries may be specified with the same MYSQL handle.
  There shouldn't be much processing per row because mysql server shouldn't
  have to wait for the client (and will not wait more than 30 sec/packet).
**************************************************************************/

static MYSQL_RES * cli_use_result(MYSQL *mysql)
{
  MYSQL_RES *result;
  DBUG_ENTER("cli_use_result");

  if (!mysql->fields)
    DBUG_RETURN(0);
  if (mysql->status != MYSQL_STATUS_GET_RESULT)
  {
    set_mysql_error(mysql, CR_COMMANDS_OUT_OF_SYNC, unknown_sqlstate);
    DBUG_RETURN(0);
  }
  if (!(result=(MYSQL_RES*) my_malloc(key_memory_MYSQL_RES,
                                      sizeof(*result)+
				      sizeof(ulong)*mysql->field_count,
				      MYF(MY_WME | MY_ZEROFILL))))
    DBUG_RETURN(0);
  result->lengths=(ulong*) (result+1);
  result->methods= mysql->methods;
  if (!(result->row=(MYSQL_ROW)
	my_malloc(key_memory_MYSQL_ROW,
                  sizeof(result->row[0])*(mysql->field_count+1), MYF(MY_WME))))
  {					/* Ptrs: to one row */
    my_free(result);
    DBUG_RETURN(0);
  }
  result->fields=	mysql->fields;
  result->field_alloc= mysql->field_alloc;
  result->field_count=	mysql->field_count;
  result->current_field=0;
  result->handle=	mysql;
  result->current_row=	0;
  mysql->fields=0;			/* fields is now in result */
  clear_alloc_root(&mysql->field_alloc);
  mysql->status=MYSQL_STATUS_USE_RESULT;
  mysql->unbuffered_fetch_owner= &result->unbuffered_fetch_cancelled;
  DBUG_RETURN(result);			/* Data is read to be fetched */
}


/**************************************************************************
  Return next row of the query results
**************************************************************************/

MYSQL_ROW STDCALL
mysql_fetch_row(MYSQL_RES *res)
{
  DBUG_ENTER("mysql_fetch_row");
  if (!res->data)
  {						/* Unbufferred fetch */
    if (!res->eof)
    {
      MYSQL *mysql= res->handle;
      if (mysql->status != MYSQL_STATUS_USE_RESULT)
      {
        set_mysql_error(mysql,
                        res->unbuffered_fetch_cancelled ? 
                        CR_FETCH_CANCELED : CR_COMMANDS_OUT_OF_SYNC,
                        unknown_sqlstate);
      }
      else if (!(read_one_row(mysql, res->field_count, res->row, res->lengths)))
      {
	res->row_count++;
	DBUG_RETURN(res->current_row=res->row);
      }
      DBUG_PRINT("info",("end of data"));
      res->eof=1;
      mysql->status=MYSQL_STATUS_READY;
      /*
        Reset only if owner points to us: there is a chance that somebody
        started new query after mysql_stmt_close():
      */
      if (mysql->unbuffered_fetch_owner == &res->unbuffered_fetch_cancelled)
        mysql->unbuffered_fetch_owner= 0;
      /* Don't clear handle in mysql_free_result */
      res->handle=0;
    }
    DBUG_RETURN((MYSQL_ROW) NULL);
  }
  {
    MYSQL_ROW tmp;
    if (!res->data_cursor)
    {
      DBUG_PRINT("info",("end of data"));
      DBUG_RETURN(res->current_row=(MYSQL_ROW) NULL);
    }
    tmp = res->data_cursor->data;
    res->data_cursor = res->data_cursor->next;
    DBUG_RETURN(res->current_row=tmp);
  }
}


/**************************************************************************
  Get column lengths of the current row
  If one uses mysql_use_result, res->lengths contains the length information,
  else the lengths are calculated from the offset between pointers.
**************************************************************************/

ulong * STDCALL
mysql_fetch_lengths(MYSQL_RES *res)
{
  MYSQL_ROW column;

  if (!(column=res->current_row))
    return 0;					/* Something is wrong */
  if (res->data)
    (*res->methods->fetch_lengths)(res->lengths, column, res->field_count);
  return res->lengths;
}

int STDCALL
mysql_options(MYSQL *mysql,enum mysql_option option, const void *arg)
{
  DBUG_ENTER("mysql_option");
  DBUG_PRINT("enter",("option: %d",(int) option));
  switch (option) {
  case MYSQL_OPT_CONNECT_TIMEOUT:
    mysql->options.connect_timeout= *(uint*) arg;
    break;
  case MYSQL_OPT_READ_TIMEOUT:
    mysql->options.read_timeout= *(uint*) arg;
    break;
  case MYSQL_OPT_WRITE_TIMEOUT:
    mysql->options.write_timeout= *(uint*) arg;
    break;
  case MYSQL_OPT_COMPRESS:
    mysql->options.compress= 1;			/* Remember for connect */
    mysql->options.client_flag|= CLIENT_COMPRESS;
    break;
  case MYSQL_OPT_NAMED_PIPE:			/* This option is depricated */
    mysql->options.protocol=MYSQL_PROTOCOL_PIPE; /* Force named pipe */
    break;
  case MYSQL_OPT_LOCAL_INFILE:			/* Allow LOAD DATA LOCAL ?*/
    if (!arg || MY_TEST(*(uint*) arg))
      mysql->options.client_flag|= CLIENT_LOCAL_FILES;
    else
      mysql->options.client_flag&= ~CLIENT_LOCAL_FILES;
    break;
  case MYSQL_INIT_COMMAND:
    add_init_command(&mysql->options,arg);
    break;
  case MYSQL_READ_DEFAULT_FILE:
    my_free(mysql->options.my_cnf_file);
    mysql->options.my_cnf_file=my_strdup(key_memory_mysql_options,
                                         arg,MYF(MY_WME));
    break;
  case MYSQL_READ_DEFAULT_GROUP:
    my_free(mysql->options.my_cnf_group);
    mysql->options.my_cnf_group=my_strdup(key_memory_mysql_options,
                                          arg,MYF(MY_WME));
    break;
  case MYSQL_SET_CHARSET_DIR:
    my_free(mysql->options.charset_dir);
    mysql->options.charset_dir=my_strdup(key_memory_mysql_options,
                                         arg,MYF(MY_WME));
    break;
  case MYSQL_SET_CHARSET_NAME:
    my_free(mysql->options.charset_name);
    mysql->options.charset_name=my_strdup(key_memory_mysql_options,
                                          arg,MYF(MY_WME));
    break;
  case MYSQL_OPT_PROTOCOL:
    mysql->options.protocol= *(uint*) arg;
    break;
  case MYSQL_SHARED_MEMORY_BASE_NAME:
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
    if (mysql->options.shared_memory_base_name != def_shared_memory_base_name)
      my_free(mysql->options.shared_memory_base_name);
    mysql->options.shared_memory_base_name=my_strdup(key_memory_mysql_options,
                                                     arg,MYF(MY_WME));
#endif
    break;
  case MYSQL_OPT_USE_REMOTE_CONNECTION:
  case MYSQL_OPT_USE_EMBEDDED_CONNECTION:
  case MYSQL_OPT_GUESS_CONNECTION:
    mysql->options.methods_to_use= option;
    break;
  case MYSQL_SET_CLIENT_IP:
    my_free(mysql->options.ci.client_ip);
    mysql->options.ci.client_ip= my_strdup(key_memory_mysql_options,
                                           arg, MYF(MY_WME));
    break;
  case MYSQL_SECURE_AUTH:
    if (!*(my_bool *) arg)
      DBUG_RETURN(1);
    break;
  case MYSQL_REPORT_DATA_TRUNCATION:
    mysql->options.report_data_truncation= MY_TEST(*(my_bool *) arg);
    break;
  case MYSQL_OPT_RECONNECT:
    mysql->reconnect= *(my_bool *) arg;
    break;
  case MYSQL_OPT_BIND:
    my_free(mysql->options.ci.bind_address);
    mysql->options.ci.bind_address= my_strdup(key_memory_mysql_options,
                                              arg, MYF(MY_WME));
    break;
  case MYSQL_OPT_SSL_VERIFY_SERVER_CERT:
    if (*(my_bool*) arg)
      mysql->options.client_flag|= CLIENT_SSL_VERIFY_SERVER_CERT;
    else
      mysql->options.client_flag&= ~CLIENT_SSL_VERIFY_SERVER_CERT;
    break;
  case MYSQL_PLUGIN_DIR:
    EXTENSION_SET_STRING(&mysql->options, plugin_dir, arg);
    break;
  case MYSQL_DEFAULT_AUTH:
    EXTENSION_SET_STRING(&mysql->options, default_auth, arg);
    break;
  case MYSQL_OPT_SSL_KEY:      SET_SSL_OPTION(ssl_key, arg);     break;
  case MYSQL_OPT_SSL_CERT:     SET_SSL_OPTION(ssl_cert, arg);    break;
  case MYSQL_OPT_SSL_CA:       SET_SSL_OPTION(ssl_ca, arg);      break;
  case MYSQL_OPT_SSL_CAPATH:   SET_SSL_OPTION(ssl_capath, arg);  break;
  case MYSQL_OPT_SSL_CIPHER:   SET_SSL_OPTION(ssl_cipher, arg);  break;
  case MYSQL_OPT_SSL_CRL:      EXTENSION_SET_SSL_STRING(&mysql->options,
                                                        ssl_crl, arg);
                               break;
  case MYSQL_OPT_SSL_CRLPATH:  EXTENSION_SET_SSL_STRING(&mysql->options,
                                                        ssl_crlpath, arg);
                               break;
  case MYSQL_OPT_SSL_ENFORCE:  ENSURE_EXTENSIONS_PRESENT(&mysql->options);
	                       mysql->options.extension->ssl_enforce=
				 (*(my_bool *) arg) ? TRUE : FALSE;
                               mysql->options.use_ssl= TRUE;
                               break;
  case MYSQL_SERVER_PUBLIC_KEY:
    EXTENSION_SET_STRING(&mysql->options, server_public_key_path, arg);
    break;

  case MYSQL_OPT_CONNECT_ATTR_RESET:
    ENSURE_EXTENSIONS_PRESENT(&mysql->options);
    if (my_hash_inited(&mysql->options.extension->connection_attributes))
    {
      my_hash_free(&mysql->options.extension->connection_attributes);
      mysql->options.extension->connection_attributes_length= 0;
    }
    break;
  case MYSQL_OPT_CONNECT_ATTR_DELETE:
    ENSURE_EXTENSIONS_PRESENT(&mysql->options);
    if (my_hash_inited(&mysql->options.extension->connection_attributes))
    {
      size_t len;
      uchar *elt;

      len= arg ? strlen(arg) : 0;

      if (len)
      {
        elt= my_hash_search(&mysql->options.extension->connection_attributes,
                            arg, len);
        if (elt)
        {
          LEX_STRING *attr= (LEX_STRING *) elt;
          LEX_STRING *key= attr, *value= attr + 1;

          mysql->options.extension->connection_attributes_length-=
            get_length_store_length(key->length) + key->length +
            get_length_store_length(value->length) + value->length;

          my_hash_delete(&mysql->options.extension->connection_attributes,
                         elt);

        }
      }
    }
    break;
  case MYSQL_ENABLE_CLEARTEXT_PLUGIN:
    ENSURE_EXTENSIONS_PRESENT(&mysql->options);
    mysql->options.extension->enable_cleartext_plugin= 
      (*(my_bool*) arg) ? TRUE : FALSE;
    break;
  case MYSQL_OPT_CAN_HANDLE_EXPIRED_PASSWORDS:
    if (*(my_bool*) arg)
      mysql->options.client_flag|= CLIENT_CAN_HANDLE_EXPIRED_PASSWORDS;
    else
      mysql->options.client_flag&= ~CLIENT_CAN_HANDLE_EXPIRED_PASSWORDS;
    break;

  default:
    DBUG_RETURN(1);
  }
  DBUG_RETURN(0);
}


/**
  Return the current values for the options settable through mysql_options()

  Returns the current values for all of the connection options.
  Callers should not manipulate the returned data !
  Data are valid at the time of returning them until the next C API CALL
  arg should always be a pointer to a variable of the appropriate type.
  type of variable, based on the parameter:

  uint
    MYSQL_OPT_CONNECT_TIMEOUT, MYSQL_OPT_READ_TIMEOUT, MYSQL_OPT_WRITE_TIMEOUT,
    MYSQL_OPT_PROTOCOL

  my_bool
    MYSQL_OPT_COMPRESS, MYSQL_OPT_LOCAL_INFILE, MYSQL_OPT_USE_REMOTE_CONNECTION,
    MYSQL_OPT_USE_EMBEDDED_CONNECTION, MYSQL_OPT_GUESS_CONNECTION,
    MYSQL_SECURE_AUTH, MYSQL_REPORT_DATA_TRUNCATION, MYSQL_OPT_RECONNECT,
    MYSQL_OPT_SSL_VERIFY_SERVER_CERT, MYSQL_OPT_SSL_ENFORCE,
    MYSQL_ENABLE_CLEARTEXT_PLUGIN, MYSQL_OPT_CAN_HANDLE_EXPIRED_PASSWORDS

  const char *
    MYSQL_READ_DEFAULT_FILE, MYSQL_READ_DEFAULT_GROUP,
    MYSQL_SET_CHARSET_DIR, MYSQL_SET_CHARSET_NAME, MYSQL_SHARED_MEMORY_BASE_NAME,
    MYSQL_SET_CLIENT_IP, MYSQL_OPT_BIND, MYSQL_PLUGIN_DIR, MYSQL_DEFAULT_AUTH,
    MYSQL_OPT_SSL_KEY, MYSQL_OPT_SSL_CERT, MYSQL_OPT_SSL_CA, MYSQL_OPT_SSL_CAPATH,
    MYSQL_OPT_SSL_CIPHER, MYSQL_OPT_SSL_CRL, MYSQL_OPT_SSL_CRLPATH,
    MYSQL_SERVER_PUBLIC_KEY

  <none, error returned>
    MYSQL_OPT_NAMED_PIPE, MYSQL_OPT_CONNECT_ATTR_RESET,
    MYSQL_OPT_CONNECT_ATTR_DELETE, MYSQL_INIT_COMMAND

  @param      mysql       The MYSQL connection to operate on
  @param      option      The option to return the value for
  @param  out arg         Must be non-null. Receives the current value.
  @return status
  @retval 0 SUCCESS
*/

int STDCALL
mysql_get_option(MYSQL *mysql, enum mysql_option option, const void *arg)
{
  DBUG_ENTER("mysql_option");
  DBUG_PRINT("enter", ("option: %d", (int)option));

  if (!arg)
    DBUG_RETURN(1);

  switch (option) {
  case MYSQL_OPT_CONNECT_TIMEOUT:
    *((uint *)arg) = mysql->options.connect_timeout;
    break;
  case MYSQL_OPT_READ_TIMEOUT:
    *((uint *)arg)= mysql->options.read_timeout;
    break;
  case MYSQL_OPT_WRITE_TIMEOUT:
    *((uint *)arg)= mysql->options.write_timeout;
    break;
  case MYSQL_OPT_COMPRESS:
    *((my_bool *)arg) = mysql->options.compress ? TRUE : FALSE;
    break;
  case MYSQL_OPT_LOCAL_INFILE:			/* Allow LOAD DATA LOCAL ?*/
    *((uint *)arg)= (mysql->options.client_flag & CLIENT_LOCAL_FILES) ?
                    TRUE : FALSE;
    break;
  case MYSQL_READ_DEFAULT_FILE:
    *((char **)arg)= mysql->options.my_cnf_file;
    break;
  case MYSQL_READ_DEFAULT_GROUP:
    *((char **)arg)= mysql->options.my_cnf_group;
    break;
  case MYSQL_SET_CHARSET_DIR:
    *((char **)arg)= mysql->options.charset_dir;
    break;
  case MYSQL_SET_CHARSET_NAME:
    *((char **)arg)= mysql->options.charset_name;
    break;
  case MYSQL_OPT_PROTOCOL:
    *((uint *)arg)= mysql->options.protocol;
    break;
  case MYSQL_SHARED_MEMORY_BASE_NAME:
#if defined (_WIN32) && !defined (EMBEDDED_LIBRARY)
    *((char **)arg)= mysql->options.shared_memory_base_name;
#else
    *((const char **)arg)= "";
#endif
    break;
  case MYSQL_OPT_USE_REMOTE_CONNECTION:
    *((my_bool *)arg)=
      (mysql->options.methods_to_use == MYSQL_OPT_USE_REMOTE_CONNECTION) ?
                                        TRUE : FALSE;
    break;
  case MYSQL_OPT_USE_EMBEDDED_CONNECTION:
    *((my_bool *)arg) =
      (mysql->options.methods_to_use == MYSQL_OPT_USE_EMBEDDED_CONNECTION) ?
    TRUE : FALSE;
    break;
  case MYSQL_OPT_GUESS_CONNECTION:
    *((my_bool *)arg) =
      (mysql->options.methods_to_use == MYSQL_OPT_GUESS_CONNECTION) ?
    TRUE : FALSE;
    break;
  case MYSQL_SET_CLIENT_IP:
    *((char **)arg) = mysql->options.ci.client_ip;
    break;
  case MYSQL_SECURE_AUTH:
    *((my_bool *)arg)= TRUE;
    break;
  case MYSQL_REPORT_DATA_TRUNCATION:
    *((my_bool *)arg)= mysql->options.report_data_truncation;
    break;
  case MYSQL_OPT_RECONNECT:
    *((my_bool *)arg)= mysql->reconnect;
    break;
  case MYSQL_OPT_BIND:
    *((char **)arg)= mysql->options.ci.bind_address;
    break;
  case MYSQL_OPT_SSL_VERIFY_SERVER_CERT:
    *((my_bool *)arg) = (mysql->options.client_flag &
                         CLIENT_SSL_VERIFY_SERVER_CERT) ? TRUE : FALSE;
    break;
  case MYSQL_PLUGIN_DIR:
    *((char **)arg)= mysql->options.extension ?
                     mysql->options.extension->plugin_dir : NULL;
    break;
  case MYSQL_DEFAULT_AUTH:
    *((char **)arg)= mysql->options.extension ?
                     mysql->options.extension->default_auth : NULL;
    break;
  case MYSQL_OPT_SSL_KEY:
    *((char **)arg)= mysql->options.ssl_key;
    break;
  case MYSQL_OPT_SSL_CERT:
    *((char **)arg)= mysql->options.ssl_cert;
    break;
  case MYSQL_OPT_SSL_CA:
    *((char **)arg)= mysql->options.ssl_ca;
    break;
  case MYSQL_OPT_SSL_CAPATH:
    *((char **)arg)= mysql->options.ssl_capath;
    break;
  case MYSQL_OPT_SSL_CIPHER:
    *((char **)arg)= mysql->options.ssl_cipher;
    break;
  case MYSQL_OPT_SSL_CRL:
    *((char **)arg)= mysql->options.extension ?
                     mysql->options.extension->ssl_crl : NULL;
    break;
  case MYSQL_OPT_SSL_CRLPATH:
    *((char **)arg)= mysql->options.extension ?
                     mysql->options.extension->ssl_crlpath : NULL;
    break;
  case MYSQL_OPT_SSL_ENFORCE:
    *((my_bool *)arg)= (mysql->options.extension &&
                        mysql->options.extension->ssl_enforce) ? TRUE : FALSE;
    break;
  case MYSQL_SERVER_PUBLIC_KEY:
    *((char **)arg)= mysql->options.extension ?
                     mysql->options.extension->server_public_key_path : NULL;
    break;
  case MYSQL_ENABLE_CLEARTEXT_PLUGIN:
    *((my_bool *)arg)= (mysql->options.extension &&
                        mysql->options.extension->enable_cleartext_plugin) ?
			TRUE : FALSE;
    break;
  case MYSQL_OPT_CAN_HANDLE_EXPIRED_PASSWORDS:
    *((my_bool*)arg)= (mysql->options.client_flag &
                       CLIENT_CAN_HANDLE_EXPIRED_PASSWORDS) ? TRUE : FALSE;
    break;

  case MYSQL_OPT_NAMED_PIPE:			/* This option is depricated */
  case MYSQL_INIT_COMMAND:                      /* Cumulative */
  case MYSQL_OPT_CONNECT_ATTR_RESET:            /* Cumulative */
  case MYSQL_OPT_CONNECT_ATTR_DELETE:           /* Cumulative */
  default:
    DBUG_RETURN(1);
  }
  DBUG_RETURN(0);
}


/**
  A function to return the key from a connection attribute
*/
uchar *
get_attr_key(LEX_STRING *part, size_t *length,
             my_bool not_used __attribute__((unused)))
{
  *length= part[0].length;
  return (uchar *) part[0].str;
}

int STDCALL
mysql_options4(MYSQL *mysql,enum mysql_option option,
               const void *arg1, const void *arg2)
{
  DBUG_ENTER("mysql_option");
  DBUG_PRINT("enter",("option: %d",(int) option));

  switch (option)
  {
  case MYSQL_OPT_CONNECT_ATTR_ADD:
    {
      LEX_STRING *elt;
      char *key, *value;
      size_t key_len= arg1 ? strlen(arg1) : 0,
             value_len= arg2 ? strlen(arg2) : 0;
      size_t attr_storage_length= key_len + value_len;

      /* we can't have a zero length key */
      if (!key_len)
      {
        set_mysql_error(mysql, CR_INVALID_PARAMETER_NO, unknown_sqlstate);
        DBUG_RETURN(1);
      }

      /* calculate the total storage length of the attribute */
      attr_storage_length+= get_length_store_length(key_len);
      attr_storage_length+= get_length_store_length(value_len);

      ENSURE_EXTENSIONS_PRESENT(&mysql->options);

      /*
        Throw and error if the maximum combined length of the attribute value
        will be greater than the maximum that we can safely transmit.
      */
      if (attr_storage_length +
          mysql->options.extension->connection_attributes_length >
          MAX_CONNECTION_ATTR_STORAGE_LENGTH)
      {
        set_mysql_error(mysql, CR_INVALID_PARAMETER_NO, unknown_sqlstate);
        DBUG_RETURN(1);
      }

      if (!my_hash_inited(&mysql->options.extension->connection_attributes))
      {
        if (my_hash_init(&mysql->options.extension->connection_attributes,
                     &my_charset_bin, 0, 0, 0, (my_hash_get_key) get_attr_key,
                     my_free, HASH_UNIQUE))
        {
          set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
          DBUG_RETURN(1);
        }
      }
      if (!my_multi_malloc(key_memory_mysql_options,
                           MY_WME,
                           &elt, 2 * sizeof(LEX_STRING),
                           &key, key_len + 1,
                           &value, value_len + 1,
                           NULL))
      {
        set_mysql_error(mysql, CR_OUT_OF_MEMORY, unknown_sqlstate);
        DBUG_RETURN(1);
      }
      elt[0].str= key; elt[0].length= key_len;
      elt[1].str= value; elt[1].length= value_len;
      if (key_len)
        memcpy(key, arg1, key_len);
      key[key_len]= 0;
      if (value_len)
        memcpy(value, arg2, value_len);
      value[value_len]= 0;
      if (my_hash_insert(&mysql->options.extension->connection_attributes,
                     (uchar *) elt))
      {
        /* can't insert the value */
        my_free(elt);
        set_mysql_error(mysql, CR_DUPLICATE_CONNECTION_ATTR,
                        unknown_sqlstate);
        DBUG_RETURN(1);
      }

      mysql->options.extension->connection_attributes_length+=
        attr_storage_length;

      break;
    }

  default:
    DBUG_RETURN(1);
  }
  DBUG_RETURN(0);
}


/****************************************************************************
  Functions to get information from the MySQL structure
  These are functions to make shared libraries more usable.
****************************************************************************/

/* MYSQL_RES */
my_ulonglong STDCALL mysql_num_rows(MYSQL_RES *res)
{
  return res->row_count;
}

unsigned int STDCALL mysql_num_fields(MYSQL_RES *res)
{
  return res->field_count;
}

uint STDCALL mysql_errno(MYSQL *mysql)
{
  return mysql ? mysql->net.last_errno : mysql_server_last_errno;
}


const char * STDCALL mysql_error(MYSQL *mysql)
{
  return mysql ? mysql->net.last_error : mysql_server_last_error;
}


/**
  Read data and its length from a LIST node.

  Assumes LIST which stores data blobs in LEX_STRING structures,
  where LEX_STRING::str is pointer to the data and LEX_STRING::length
  is the length of this data.

  If node is NULL then data and length are set to NULL and 0, respectively,
  and function returns 0, otherwise, if data has been read from the node,
  function returns 1.
*/

static int get_data_and_length(LIST *node, const char **data, size_t *length)
{
  DBUG_ASSERT(!node || node->data);
  if (data)
    *data= node ? ((LEX_STRING*)(node->data))->str : NULL;
  if (length)
    *length= node ? ((LEX_STRING*)(node->data))->length : 0;

  return node ? 0 : 1;
}


/**
  Get the first state change information received from the server.

  @param mysql  [IN]        mysql handle
  @param type   [IN]        state change type
  @param data   [OUT]       buffer to store the data
  @param length [OUT]       length of the data

  @return
    0 - Valid data stored
    1 - No data
*/

int STDCALL mysql_session_track_get_first(MYSQL *mysql,
                                          enum enum_session_state_type type,
                                          const char **data,
                                          size_t *length)
{
  STATE_INFO *info= STATE_DATA(mysql);

  if (!info || !IS_SESSION_STATE_TYPE(type)
            || !(info->info_list[type].head_node))
    return get_data_and_length(NULL, data, length);

  info->info_list[type].current_node= info->info_list[type].head_node;

  return mysql_session_track_get_next(mysql, type, data, length);
}


/**
  Get the subsequent state change information received from the server.

  @param mysql  [IN]        mysql handle
  @param type   [IN]        state change type
  @param data   [OUT]       buffer to store the data
  @param length [OUT]       length of the data

  @return
    0 - Valid data stored
    1 - No data
*/

int STDCALL mysql_session_track_get_next(MYSQL *mysql,
                                         enum enum_session_state_type type,
                                         const char **data,
                                         size_t *length)
{
  STATE_INFO *info= STATE_DATA(mysql);
  int ret;

  if (!info || !IS_SESSION_STATE_TYPE(type)
            || !(info->info_list[type].current_node))
    return get_data_and_length(NULL, data, length);

  ret= get_data_and_length(info->info_list[type].current_node,
                           data, length);

  info->info_list[type].current_node= list_rest(info->info_list[type].current_node);

  return ret;
}


/*
  Get version number for server in a form easy to test on

  SYNOPSIS
    mysql_get_server_version()
    mysql		Connection

  EXAMPLE
    4.1.0-alfa ->  40100
  
  NOTES
    We will ensure that a newer server always has a bigger number.

  RETURN
   Signed number > 323000
   Zero if there is no connection
*/

ulong STDCALL
mysql_get_server_version(MYSQL *mysql)
{
  ulong major= 0, minor= 0, version= 0;

  if (mysql->server_version)
  {
    char *pos= mysql->server_version, *end_pos;
    major=   strtoul(pos, &end_pos, 10);	pos=end_pos+1;
    minor=   strtoul(pos, &end_pos, 10);	pos=end_pos+1;
    version= strtoul(pos, &end_pos, 10);
  }
  else
  {
    set_mysql_error(mysql, CR_COMMANDS_OUT_OF_SYNC, unknown_sqlstate);
  }

  return major*10000 + minor*100 + version;
}


/* 
   mysql_set_character_set function sends SET NAMES cs_name to
   the server (which changes character_set_client, character_set_result
   and character_set_connection) and updates mysql->charset so other
   functions like mysql_real_escape will work correctly.
*/
int STDCALL mysql_set_character_set(MYSQL *mysql, const char *cs_name)
{
  struct charset_info_st *cs;
  const char *save_csdir= charsets_dir;

  if (mysql->options.charset_dir)
    charsets_dir= mysql->options.charset_dir;

  if (!mysql->net.vio)
  {
    /* Initialize with automatic OS character set detection. */
    mysql_options(mysql, MYSQL_SET_CHARSET_NAME, cs_name);
    mysql_init_character_set(mysql);
    /* 
      In case of automatic OS character set detection
      mysql_init_character_set changes mysql->options.charset_name
      from "auto" to the real character set name.
      Reset cs_name to the detected character set name, accordingly.
    */
    cs_name= mysql->options.charset_name;
  }

  if (strlen(cs_name) < MY_CS_NAME_SIZE &&
     (cs= get_charset_by_csname(cs_name, MY_CS_PRIMARY, MYF(0))))
  {
    char buff[MY_CS_NAME_SIZE + 10];
    charsets_dir= save_csdir;
    if (!mysql->net.vio)
    {
      /* If there is no connection yet we don't send "SET NAMES" query */
      mysql->charset= cs;
      return 0;
    }
    /* Skip execution of "SET NAMES" for pre-4.1 servers */
    if (mysql_get_server_version(mysql) < 40100)
      return 0;
    sprintf(buff, "SET NAMES %s", cs_name);
    if (!mysql_real_query(mysql, buff, (ulong) strlen(buff)))
    {
      mysql->charset= cs;
    }
  }
  else
  {
    char cs_dir_name[FN_REFLEN];
    get_charsets_dir(cs_dir_name);
    set_mysql_extended_error(mysql, CR_CANT_READ_CHARSET, unknown_sqlstate,
                             ER(CR_CANT_READ_CHARSET), cs_name, cs_dir_name);
  }
  charsets_dir= save_csdir;
  return mysql->net.last_errno;
}

/**
  client authentication plugin that does native MySQL authentication
  using a 20-byte (4.1+) scramble
*/
static int native_password_auth_client(MYSQL_PLUGIN_VIO *vio, MYSQL *mysql)
{
  int pkt_len;
  uchar *pkt;

  DBUG_ENTER("native_password_auth_client");


  if (((MCPVIO_EXT *)vio)->mysql_change_user)
  {
    /*
      in mysql_change_user() the client sends the first packet.
      we use the old scramble.
    */
    pkt= (uchar*)mysql->scramble;
    pkt_len= SCRAMBLE_LENGTH + 1;
  }
  else
  {
    /* read the scramble */
    if ((pkt_len= vio->read_packet(vio, &pkt)) < 0)
      DBUG_RETURN(CR_ERROR);

    if (pkt_len != SCRAMBLE_LENGTH + 1)
      DBUG_RETURN(CR_SERVER_HANDSHAKE_ERR);

    /* save it in MYSQL */
    memcpy(mysql->scramble, pkt, SCRAMBLE_LENGTH);
    mysql->scramble[SCRAMBLE_LENGTH] = 0;
  }

  if (mysql->passwd[0])
  {
    char scrambled[SCRAMBLE_LENGTH + 1];
    DBUG_PRINT("info", ("sending scramble"));
    scramble(scrambled, (char*)pkt, mysql->passwd);
    if (vio->write_packet(vio, (uchar*)scrambled, SCRAMBLE_LENGTH))
      DBUG_RETURN(CR_ERROR);
  }
  else
  {
    DBUG_PRINT("info", ("no password"));
    if (vio->write_packet(vio, 0, 0)) /* no password */
      DBUG_RETURN(CR_ERROR);
  }

  DBUG_RETURN(CR_OK);
}

/**
  The main function of the mysql_clear_password authentication plugin.
*/

static int clear_password_auth_client(MYSQL_PLUGIN_VIO *vio, MYSQL *mysql)
{
  int res;

  /* send password in clear text */
  res= vio->write_packet(vio, (const unsigned char *) mysql->passwd, 
						 (int)strlen(mysql->passwd) + 1);

  return res ? CR_ERROR : CR_OK;
}


