thread.c

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/*
 * msvcrt.dll thread functions
 *
 * Copyright 2000 Jon Griffiths
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser 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
 */

#include <precomp.h>
#include <internal/wine/msvcrt.h>

#include <malloc.h>
#include <process.h>

#include <debug.h>

void _amsg_exit (int errnum);
/* Index to TLS */
DWORD MSVCRT_tls_index;

typedef void (*_beginthread_start_routine_t)(void *);
typedef unsigned int (__stdcall *_beginthreadex_start_routine_t)(void *);

/********************************************************************/

typedef struct {
  _beginthread_start_routine_t start_address;
  void *arglist;
} _beginthread_trampoline_t;

/*********************************************************************
 *		msvcrt_get_thread_data
 *
 * Return the thread local storage structure.
 */
MSVCRT_thread_data *msvcrt_get_thread_data(void)
{
    MSVCRT_thread_data *ptr;
    DWORD err = GetLastError();  /* need to preserve last error */

    if (!(ptr = TlsGetValue( MSVCRT_tls_index )))
    {
        if (!(ptr = HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*ptr) )))
		    _amsg_exit( _RT_THREAD );
        if (!TlsSetValue( MSVCRT_tls_index, ptr ))
			_amsg_exit( _RT_THREAD );
        if (!TlsSetValue( MSVCRT_tls_index, ptr ))
			_amsg_exit( _RT_THREAD );
    }
    SetLastError( err );
    return ptr;
}

/*********************************************************************
 *		_beginthread_trampoline
 */
static DWORD CALLBACK _beginthread_trampoline(LPVOID arg)
{
    _beginthread_trampoline_t local_trampoline;

    /* Maybe it's just being paranoid, but freeing arg right
     * away seems safer.
     */
    memcpy(&local_trampoline,arg,sizeof(local_trampoline));
	free(arg);

    local_trampoline.start_address(local_trampoline.arglist);
    return 0;
}

/*********************************************************************
 *		_beginthread (MSVCRT.@)
 */
unsigned long _beginthread(
  _beginthread_start_routine_t start_address, /* [in] Start address of routine that begins execution of new thread */
  unsigned int stack_size, /* [in] Stack size for new thread or 0 */
  void *arglist)           /* [in] Argument list to be passed to new thread or NULL */
{
  _beginthread_trampoline_t* trampoline;

  DPRINT("(%p, %d, %p)\n", start_address, stack_size, arglist);

  /* Allocate the trampoline here so that it is still valid when the thread
   * starts... typically after this function has returned.
   * _beginthread_trampoline is responsible for freeing the trampoline
   */
  trampoline=malloc(sizeof(*trampoline));
  trampoline->start_address = start_address;
  trampoline->arglist = arglist;

  /* FIXME */
  return (unsigned long)CreateThread(NULL, stack_size, _beginthread_trampoline,
				     trampoline, 0, NULL);
}