mutex.c

 
#include <winpr/config.h>
 
#include <winpr/synch.h>
#include <winpr/debug.h>
#include <winpr/wlog.h>
#include <winpr/string.h>
 
#include "synch.h"
 
#ifndef _WIN32
 
#include <errno.h>
 
#include "../handle/handle.h"
 
#include "../log.h"
#define TAG WINPR_TAG("sync.mutex")
 
static BOOL MutexCloseHandle(HANDLE handle);
 
static BOOL MutexIsHandled(HANDLE handle)
{
  return WINPR_HANDLE_IS_HANDLED(handle, HANDLE_TYPE_MUTEX, FALSE);
}
 
static int MutexGetFd(HANDLE handle)
{
  WINPR_MUTEX* mux = (WINPR_MUTEX*)handle;
 
  if (!MutexIsHandled(handle))
    return -1;
 
  /* TODO: Mutex does not support file handles... */
  (void)mux;
  return -1;
}
 
BOOL MutexCloseHandle(HANDLE handle)
{
  WINPR_MUTEX* mutex = (WINPR_MUTEX*)handle;
  int rc = 0;
 
  if (!MutexIsHandled(handle))
    return FALSE;
 
  if ((rc = pthread_mutex_destroy(&mutex->mutex)))
  {
    char ebuffer[256] = WINPR_C_ARRAY_INIT;
    WLog_ERR(TAG, "pthread_mutex_destroy failed with %s [%d]",
             winpr_strerror(rc, ebuffer, sizeof(ebuffer)), rc);
#if defined(WITH_DEBUG_MUTEX)
    {
      size_t used = 0;
      void* stack = winpr_backtrace(20);
      char** msg = nullptr;
 
      if (stack)
        msg = winpr_backtrace_symbols(stack, &used);
 
      if (msg)
      {
        for (size_t i = 0; i < used; i++)
          WLog_ERR(TAG, "%2" PRIdz ": %s", i, msg[i]);
      }
 
      free(msg);
      winpr_backtrace_free(stack);
    }
#endif
  }
 
  free(mutex->name);
  free(handle);
  return TRUE;
}
 
static HANDLE_OPS ops = { MutexIsHandled, MutexCloseHandle, MutexGetFd, nullptr, /* CleanupHandle */
                        nullptr,        nullptr,          nullptr,    nullptr, nullptr, nullptr,
                        nullptr,        nullptr,          nullptr,    nullptr, nullptr, nullptr,
                        nullptr,        nullptr,          nullptr,    nullptr, nullptr };
 
HANDLE CreateMutexW(LPSECURITY_ATTRIBUTES lpMutexAttributes, BOOL bInitialOwner, LPCWSTR lpName)
{
  HANDLE handle = nullptr;
  char* name = nullptr;
 
  if (lpName)
  {
    name = ConvertWCharToUtf8Alloc(lpName, nullptr);
    if (!name)
      return nullptr;
  }
 
  handle = CreateMutexA(lpMutexAttributes, bInitialOwner, name);
  free(name);
  return handle;
}
 
HANDLE CreateMutexA(LPSECURITY_ATTRIBUTES lpMutexAttributes, BOOL bInitialOwner, LPCSTR lpName)
{
  HANDLE handle = nullptr;
  WINPR_MUTEX* mutex = nullptr;
  mutex = (WINPR_MUTEX*)calloc(1, sizeof(WINPR_MUTEX));
 
  if (lpMutexAttributes)
    WLog_WARN(TAG, "[%s] does not support lpMutexAttributes", lpName);
 
  if (mutex)
  {
    pthread_mutexattr_t attr;
    pthread_mutexattr_init(&attr);
    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
    pthread_mutex_init(&mutex->mutex, &attr);
    WINPR_HANDLE_SET_TYPE_AND_MODE(mutex, HANDLE_TYPE_MUTEX, WINPR_FD_READ);
    mutex->common.ops = &ops;
    handle = (HANDLE)mutex;
 
    if (bInitialOwner)
      pthread_mutex_lock(&mutex->mutex);
 
    if (lpName)
      mutex->name = strdup(lpName); /* Non runtime relevant information, skip nullptr check */
  }
 
  return handle;
}
 
HANDLE CreateMutexExA(LPSECURITY_ATTRIBUTES lpMutexAttributes, LPCSTR lpName, DWORD dwFlags,
                      DWORD dwDesiredAccess)
{
  BOOL initial = FALSE;
  /* TODO: support access modes */
 
  if (dwDesiredAccess != 0)
    WLog_WARN(TAG, "[%s] does not support dwDesiredAccess 0x%08" PRIx32, lpName,
              dwDesiredAccess);
 
  if (dwFlags & CREATE_MUTEX_INITIAL_OWNER)
    initial = TRUE;
 
  return CreateMutexA(lpMutexAttributes, initial, lpName);
}
 
HANDLE CreateMutexExW(LPSECURITY_ATTRIBUTES lpMutexAttributes, LPCWSTR lpName, DWORD dwFlags,
                      DWORD dwDesiredAccess)
{
  BOOL initial = FALSE;
 
  /* TODO: support access modes */
  if (dwDesiredAccess != 0)
  {
    char name[MAX_PATH] = WINPR_C_ARRAY_INIT;
    ConvertWCharToUtf8(lpName, name, sizeof(name) - 1);
    WLog_WARN(TAG, "[%s] does not support dwDesiredAccess 0x%08" PRIx32, name, dwDesiredAccess);
  }
 
  if (dwFlags & CREATE_MUTEX_INITIAL_OWNER)
    initial = TRUE;
 
  return CreateMutexW(lpMutexAttributes, initial, lpName);
}
 
HANDLE OpenMutexA(DWORD dwDesiredAccess, BOOL bInheritHandle, LPCSTR lpName)
{
  /* TODO: Implement */
  WINPR_UNUSED(dwDesiredAccess);
  WINPR_UNUSED(bInheritHandle);
  WINPR_UNUSED(lpName);
  WLog_ERR(TAG, "TODO: Implement");
  return nullptr;
}
 
HANDLE OpenMutexW(DWORD dwDesiredAccess, BOOL bInheritHandle, LPCWSTR lpName)
{
  /* TODO: Implement */
  WINPR_UNUSED(dwDesiredAccess);
  WINPR_UNUSED(bInheritHandle);
  WINPR_UNUSED(lpName);
  WLog_ERR(TAG, "TODO: Implement");
  return nullptr;
}
 
BOOL ReleaseMutex(HANDLE hMutex)
{
  ULONG Type = 0;
  WINPR_HANDLE* Object = nullptr;
 
  if (!winpr_Handle_GetInfo(hMutex, &Type, &Object))
    return FALSE;
 
  if (Type == HANDLE_TYPE_MUTEX)
  {
    WINPR_MUTEX* mutex = (WINPR_MUTEX*)Object;
    int rc = pthread_mutex_unlock(&mutex->mutex);
 
    if (rc)
    {
      char ebuffer[256] = WINPR_C_ARRAY_INIT;
      WLog_ERR(TAG, "pthread_mutex_unlock failed with %s [%d]",
               winpr_strerror(rc, ebuffer, sizeof(ebuffer)), rc);
      return FALSE;
    }
 
    return TRUE;
  }
 
  return FALSE;
}
 
#endif