/* Copyright (c) 2001, 2023, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   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, version 2.0, 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 */

#include <my_global.h>
#include <mysql.h>
#include <mysqld_error.h>
#include <my_thread.h>
#include <my_sys.h>
#include <mysys_err.h>
#include <m_string.h>
#include <m_ctype.h>
#include "errmsg.h"
#include <violite.h>
#include <sys/stat.h>
#include <signal.h>
#include <time.h>
#include <sql_common.h>
#include "embedded_priv.h"
#include "client_settings.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 INADDR_NONE
#define INADDR_NONE	-1
#endif

ulong net_buffer_length;
ulong max_allowed_packet;

#if defined(_WIN32)
#define ERRNO WSAGetLastError()
#define perror(A)
#else
#include <errno.h>
#define ERRNO errno
#define SOCKET_ERROR -1
#define closesocket(A) close(A)
#endif

#ifdef HAVE_GETPWUID
struct passwd *getpwuid(uid_t);
char* getlogin(void);
#endif

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


int mysql_init_character_set(MYSQL *mysql);

MYSQL * STDCALL
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 name_buff[USERNAME_LENGTH + 1];

  DBUG_ENTER("mysql_real_connect");
  DBUG_PRINT("enter",("host: %s  db: %s  user: %s (libmysqld)",
		      host ? host : "(Null)",
		      db ? db : "(Null)",
		      user ? user : "(Null)"));

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

  if (!host || !host[0])
    host= mysql->options.host;

  if (mysql->options.methods_to_use == MYSQL_OPT_USE_REMOTE_CONNECTION ||
      (mysql->options.methods_to_use == MYSQL_OPT_GUESS_CONNECTION &&
       host && *host && strcmp(host,LOCAL_HOST)))
    DBUG_RETURN(cli_mysql_real_connect(mysql, host, user, 
				       passwd, db, port, 
				       unix_socket, client_flag));

  mysql->methods= &embedded_methods;

  /* 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;
  }

  if (!db || !db[0])
    db=mysql->options.db;

  if (!user || !user[0])
    user=mysql->options.user;

#ifndef NO_EMBEDDED_ACCESS_CHECKS
  if (!passwd)
  {
    passwd=mysql->options.password;
    if (!passwd)
      passwd=getenv("MYSQL_PWD");		/* get it from environment */
  }
  mysql->passwd= passwd ? my_strdup(PSI_NOT_INSTRUMENTED,
                                    passwd,MYF(0)) : NULL;
#endif /*!NO_EMBEDDED_ACCESS_CHECKS*/
  if (!user || !user[0])
  {
    read_user_name(name_buff);
    if (name_buff[0])
      user= name_buff;
  }

  if (!user)
    user= "";
   /* 
      We need to alloc some space for mysql->info but don't want to
      put extra 'my_free's in mysql_close.
      So we alloc it with the 'user' string to be freed at once
   */
  mysql->user= my_strdup(PSI_NOT_INSTRUMENTED,
                         user, MYF(0));

  port=0;
  unix_socket=0;

  client_flag|=mysql->options.client_flag;
  /* Send client information for access check */
  client_flag|=CLIENT_CAPABILITIES;
  if (client_flag & CLIENT_MULTI_STATEMENTS)
    client_flag|= CLIENT_MULTI_RESULTS;
  /*
    no compression in embedded as we don't send any data,
    and no pluggable auth, as we cannot do a client-server dialog
  */
  client_flag&= ~(CLIENT_COMPRESS | CLIENT_PLUGIN_AUTH);
  if (db)
    client_flag|=CLIENT_CONNECT_WITH_DB;

  if (embedded_ssl_check(mysql))
    goto error;

  mysql->info_buffer= my_malloc(PSI_NOT_INSTRUMENTED,
                                MYSQL_ERRMSG_SIZE, MYF(0));
  mysql->thd= create_embedded_thd(client_flag);

  init_embedded_mysql(mysql, client_flag);

  if (mysql_init_character_set(mysql))
    goto error;

  if (check_embedded_connection(mysql, db))
    goto error;

  mysql->server_status= SERVER_STATUS_AUTOCOMMIT;

  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++)
    {
      MYSQL_RES *res;
      if (mysql_query(mysql,*ptr))
	goto error;
      if (mysql->fields)
      {
	if (!(res= (*mysql->methods->use_result)(mysql)))
	  goto error;
	mysql_free_result(res);
      }
    }
  }

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

error:
  DBUG_PRINT("error",("message: %u (%s)",
                      mysql->net.last_errno,
                      mysql->net.last_error));
  {
    /* Free alloced memory */
    my_bool free_me=mysql->free_me;
    free_old_query(mysql); 
    mysql->free_me=0;
    mysql_close(mysql);
    mysql->free_me=free_me;
  }
  DBUG_RETURN(0);
}