mariadb/libmysql/dll.c

/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
   
   This library 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
   Library General Public License for more details.
   
   You should have received a copy of the GNU Library General Public
   License along with this library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
   MA 02111-1307, USA */

/*
** Handling initialization of the dll library
*/

#include <my_global.h>
#include <my_sys.h>
#include <my_pthread.h>

static bool libmysql_inited=0;

void libmysql_init(void)
{
  if (libmysql_inited)
    return;
  libmysql_inited=1;
  my_init();
  {
    DBUG_ENTER("libmysql_init");
#ifdef LOG_ALL
    DBUG_PUSH("d:t:S:O,c::\\tmp\\libmysql.log");
#else
    if (getenv("LIBMYSQL_LOG") != NULL)
      DBUG_PUSH(getenv("LIBMYSQL_LOG"));
#endif
    DBUG_VOID_RETURN;
  }
}

#ifdef __WIN__

static int inited=0,threads=0;
HINSTANCE NEAR s_hModule;	/* Saved module handle */
DWORD main_thread;

BOOL APIENTRY LibMain(HANDLE hInst,DWORD ul_reason_being_called,
		      LPVOID lpReserved)
{
  switch (ul_reason_being_called) {
  case DLL_PROCESS_ATTACH:	/* case of libentry call in win 3.x */
    if (!inited++)
    {
      s_hModule=hInst;
      libmysql_init();
      main_thread=GetCurrentThreadId();
    }
    break;
  case DLL_THREAD_ATTACH:
    threads++;
    my_thread_init();
    break;
  case DLL_PROCESS_DETACH:	/* case of wep call in win 3.x */
     if (!--inited)		/* Safety */
     {
       /* my_thread_init() */	/* This may give extra safety */
       my_end(0);
     }
    break;
  case DLL_THREAD_DETACH:
    /* Main thread will free by my_end() */
    threads--;
    if (main_thread != GetCurrentThreadId())
      my_thread_end();
    break;
  default:
    break;
  } /* switch */

  return TRUE;

  UNREFERENCED_PARAMETER(lpReserved);
} /* LibMain */

int __stdcall DllMain(HANDLE hInst,DWORD ul_reason_being_called,LPVOID lpReserved)
{
  return LibMain(hInst,ul_reason_being_called,lpReserved);
}

#elif defined(WINDOWS)

/****************************************************************************
**	This routine is called by LIBSTART.ASM at module load time.  All it
**	does in this sample is remember the DLL module handle.	The module
**	handle is needed if you want to do things like load stuff from the
**	resource file (for instance string resources).
****************************************************************************/

int _export FAR PASCAL libmain(HANDLE hModule,short cbHeapSize,
			       UCHAR FAR *lszCmdLine)
{
  s_hModule = hModule;
  libmysql_init();
  return TRUE;
}

#endif

#ifdef OS2

//
// This function is called automatically by _DLL_InitTerm
// Every dll runtime enviroment is not tz enabled, so tzset()
// must be called to enable TZ handling
// Also timezone is fixed.
//
extern "C" unsigned long _System DllMain(unsigned long modhandle,
                                        unsigned long flag)
{
   if (flag == 0) {
      tzset();			// Set tzname
      time_t currentTime = time(NULL);
      struct tm *ts = localtime(&currentTime);
      if (ts->tm_isdst > 0)
         _timezone -= 3600;
   }
}

#endif