Allow usage of the new Condition Variable code with Critical Sections

Vista and later provide the SleepConditionVariableCS() function for this.

Since SDL_syscond_srw.c doesn't require SRW locks anymore, rename it to
SDL_syscond_cv.c which better reflects the implementation of condition
variables rather than the implementation of mutexes.

Fixes #4051.
This commit is contained in:
Cameron Gutman 2021-08-23 21:16:58 -04:00 committed by Ryan C. Gordon
parent 44ab04fc63
commit 5dccffd7e4
7 changed files with 77 additions and 63 deletions

View file

@ -1596,7 +1596,7 @@ elseif(WINDOWS)
set(SDL_THREAD_WINDOWS 1)
set(SOURCE_FILES ${SOURCE_FILES}
${SDL2_SOURCE_DIR}/src/thread/generic/SDL_syscond.c
${SDL2_SOURCE_DIR}/src/thread/windows/SDL_syscond_srw.c
${SDL2_SOURCE_DIR}/src/thread/windows/SDL_syscond_cv.c
${SDL2_SOURCE_DIR}/src/thread/windows/SDL_sysmutex.c
${SDL2_SOURCE_DIR}/src/thread/windows/SDL_syssem.c
${SDL2_SOURCE_DIR}/src/thread/windows/SDL_systhread.c

View file

@ -559,7 +559,7 @@
<ClCompile Include="..\..\src\stdlib\SDL_strtokr.c" />
<ClCompile Include="..\..\src\thread\generic\SDL_syscond.c" />
<ClCompile Include="..\..\src\thread\SDL_thread.c" />
<ClCompile Include="..\..\src\thread\windows\SDL_syscond_srw.c" />
<ClCompile Include="..\..\src\thread\windows\SDL_syscond_cv.c" />
<ClCompile Include="..\..\src\thread\windows\SDL_sysmutex.c" />
<ClCompile Include="..\..\src\thread\windows\SDL_syssem.c" />
<ClCompile Include="..\..\src\thread\windows\SDL_systhread.c" />

View file

@ -1201,7 +1201,7 @@
<ClCompile Include="..\..\src\thread\SDL_thread.c">
<Filter>thread</Filter>
</ClCompile>
<ClCompile Include="..\..\src\thread\windows\SDL_syscond_srw.c">
<ClCompile Include="..\..\src\thread\windows\SDL_syscond_cv.c" />
<Filter>thread\windows</Filter>
</ClCompile>
<ClCompile Include="..\..\src\thread\windows\SDL_sysmutex.c">

View file

@ -1547,9 +1547,6 @@ extern "C" {
* They offer better performance, allocate no kernel ressources and
* use less memory. SDL will fall back to Critical Sections on older
* OS versions or if forced to by this hint.
* This also affects Condition Variables. When SRW mutexes are used,
* SDL will use Windows Condition Variables as well. Else, a generic
* SDL_cond implementation will be used that works with all mutexes.
*
* This variable can be set to the following values:
* "0" - Use SRW Locks when available. If not, fall back to Critical Sections. (default)

View file

@ -62,29 +62,32 @@ typedef struct CONDITION_VARIABLE {
#define pWakeConditionVariable WakeConditionVariable
#define pWakeAllConditionVariable WakeAllConditionVariable
#define pSleepConditionVariableSRW SleepConditionVariableSRW
#define pSleepConditionVariableCS SleepConditionVariableCS
#else
typedef VOID(WINAPI *pfnWakeConditionVariable)(PCONDITION_VARIABLE);
typedef VOID(WINAPI *pfnWakeAllConditionVariable)(PCONDITION_VARIABLE);
typedef BOOL(WINAPI *pfnSleepConditionVariableSRW)(PCONDITION_VARIABLE, PSRWLOCK, DWORD, ULONG);
typedef BOOL(WINAPI* pfnSleepConditionVariableCS)(PCONDITION_VARIABLE, PCRITICAL_SECTION, DWORD);
static pfnWakeConditionVariable pWakeConditionVariable = NULL;
static pfnWakeAllConditionVariable pWakeAllConditionVariable = NULL;
static pfnSleepConditionVariableSRW pSleepConditionVariableSRW = NULL;
static pfnSleepConditionVariableCS pSleepConditionVariableCS = NULL;
#endif
typedef struct SDL_cond_srw
typedef struct SDL_cond_cv
{
CONDITION_VARIABLE cond;
} SDL_cond_srw;
} SDL_cond_cv;
static SDL_cond *
SDL_CreateCond_srw(void)
SDL_CreateCond_cv(void)
{
SDL_cond_srw *cond;
SDL_cond_cv *cond;
/* Relies on CONDITION_VARIABLE_INIT == 0. */
cond = (SDL_cond_srw *) SDL_calloc(1, sizeof(*cond));
cond = (SDL_cond_cv *) SDL_calloc(1, sizeof(*cond));
if (!cond) {
SDL_OutOfMemory();
}
@ -93,7 +96,7 @@ SDL_CreateCond_srw(void)
}
static void
SDL_DestroyCond_srw(SDL_cond * cond)
SDL_DestroyCond_cv(SDL_cond * cond)
{
if (cond) {
/* There are no kernel allocated resources */
@ -102,9 +105,9 @@ SDL_DestroyCond_srw(SDL_cond * cond)
}
static int
SDL_CondSignal_srw(SDL_cond * _cond)
SDL_CondSignal_cv(SDL_cond * _cond)
{
SDL_cond_srw *cond = (SDL_cond_srw *)_cond;
SDL_cond_cv *cond = (SDL_cond_cv *)_cond;
if (!cond) {
return SDL_SetError("Passed a NULL condition variable");
}
@ -115,9 +118,9 @@ SDL_CondSignal_srw(SDL_cond * _cond)
}
static int
SDL_CondBroadcast_srw(SDL_cond * _cond)
SDL_CondBroadcast_cv(SDL_cond * _cond)
{
SDL_cond_srw *cond = (SDL_cond_srw *)_cond;
SDL_cond_cv *cond = (SDL_cond_cv *)_cond;
if (!cond) {
return SDL_SetError("Passed a NULL condition variable");
}
@ -128,30 +131,32 @@ SDL_CondBroadcast_srw(SDL_cond * _cond)
}
static int
SDL_CondWaitTimeout_srw(SDL_cond * _cond, SDL_mutex * _mutex, Uint32 ms)
SDL_CondWaitTimeout_cv(SDL_cond * _cond, SDL_mutex * _mutex, Uint32 ms)
{
SDL_cond_srw *cond = (SDL_cond_srw *)_cond;
SDL_mutex_srw *mutex = (SDL_mutex_srw *)_mutex;
SDL_cond_cv *cond = (SDL_cond_cv *)_cond;
DWORD timeout;
int ret;
if (!cond) {
return SDL_SetError("Passed a NULL condition variable");
}
if (!mutex) {
if (!_mutex) {
return SDL_SetError("Passed a NULL mutex");
}
if (mutex->count != 1 || mutex->owner != GetCurrentThreadId()) {
return SDL_SetError("Passed mutex is not locked or locked recursively");
}
if (ms == SDL_MUTEX_MAXWAIT) {
timeout = INFINITE;
} else {
timeout = (DWORD) ms;
}
if (SDL_mutex_impl_active.Type == SDL_MUTEX_SRW) {
SDL_mutex_srw *mutex = (SDL_mutex_srw *)_mutex;
if (mutex->count != 1 || mutex->owner != GetCurrentThreadId()) {
return SDL_SetError("Passed mutex is not locked or locked recursively");
}
/* The mutex must be updated to the released state */
mutex->count = 0;
mutex->owner = 0;
@ -170,23 +175,38 @@ SDL_CondWaitTimeout_srw(SDL_cond * _cond, SDL_mutex * _mutex, Uint32 ms)
SDL_assert(mutex->count == 0 && mutex->owner == 0);
mutex->count = 1;
mutex->owner = GetCurrentThreadId();
} else {
SDL_mutex_cs *mutex = (SDL_mutex_cs *)_mutex;
SDL_assert(SDL_mutex_impl_active.Type == SDL_MUTEX_CS);
if (pSleepConditionVariableCS(&cond->cond, &mutex->cs, timeout) == FALSE) {
if (GetLastError() == ERROR_TIMEOUT) {
ret = SDL_MUTEX_TIMEDOUT;
} else {
ret = SDL_SetError("SleepConditionVariableCS() failed");
}
} else {
ret = 0;
}
}
return ret;
}
static int
SDL_CondWait_srw(SDL_cond * cond, SDL_mutex * mutex) {
return SDL_CondWaitTimeout_srw(cond, mutex, SDL_MUTEX_MAXWAIT);
SDL_CondWait_cv(SDL_cond * cond, SDL_mutex * mutex) {
return SDL_CondWaitTimeout_cv(cond, mutex, SDL_MUTEX_MAXWAIT);
}
static const SDL_cond_impl_t SDL_cond_impl_srw =
static const SDL_cond_impl_t SDL_cond_impl_cv =
{
&SDL_CreateCond_srw,
&SDL_DestroyCond_srw,
&SDL_CondSignal_srw,
&SDL_CondBroadcast_srw,
&SDL_CondWait_srw,
&SDL_CondWaitTimeout_srw,
&SDL_CreateCond_cv,
&SDL_DestroyCond_cv,
&SDL_CondSignal_cv,
&SDL_CondBroadcast_cv,
&SDL_CondWait_cv,
&SDL_CondWaitTimeout_cv,
};
/**
@ -222,27 +242,24 @@ SDL_CreateCond(void)
SDL_assert(SDL_mutex_impl_active.Type != SDL_MUTEX_INVALID);
}
/* It is required SRW Locks are used */
if (SDL_mutex_impl_active.Type == SDL_MUTEX_SRW) {
#if __WINRT__
/* Link statically on this platform */
impl = &SDL_cond_impl_srw;
impl = &SDL_cond_impl_cv;
#else
{
HMODULE kernel32 = GetModuleHandle(TEXT("kernel32.dll"));
if (kernel32) {
pWakeConditionVariable = (pfnWakeConditionVariable) GetProcAddress(kernel32, "WakeConditionVariable");
pWakeAllConditionVariable = (pfnWakeAllConditionVariable) GetProcAddress(kernel32, "WakeAllConditionVariable");
pSleepConditionVariableSRW = (pfnSleepConditionVariableSRW) GetProcAddress(kernel32, "SleepConditionVariableSRW");
if (pWakeConditionVariable && pWakeAllConditionVariable && pSleepConditionVariableSRW) {
pSleepConditionVariableCS = (pfnSleepConditionVariableCS) GetProcAddress(kernel32, "SleepConditionVariableCS");
if (pWakeConditionVariable && pWakeAllConditionVariable && pSleepConditionVariableSRW && pSleepConditionVariableCS) {
/* Use the Windows provided API */
impl = &SDL_cond_impl_srw;
impl = &SDL_cond_impl_cv;
}
}
if (!(kernel32 && pWakeConditionVariable && pWakeAllConditionVariable && pSleepConditionVariableSRW)) {
SDL_LogWarn(SDL_LOG_CATEGORY_SYSTEM, "Could not load required imports for SRW Condition Variables although SRW Locks are used!");
}
#endif
}
SDL_memcpy(&SDL_cond_impl_active, impl, sizeof(SDL_cond_impl_active));
}

View file

@ -169,11 +169,6 @@ static const SDL_mutex_impl_t SDL_mutex_impl_srw =
* Fallback Mutex implementation using Critical Sections (before Win 7)
*/
typedef struct SDL_mutex_cs
{
CRITICAL_SECTION cs;
} SDL_mutex_cs;
/* Create a mutex */
static SDL_mutex *
SDL_CreateMutex_cs(void)

View file

@ -66,4 +66,9 @@ typedef struct SDL_mutex_srw
DWORD owner;
} SDL_mutex_srw;
typedef struct SDL_mutex_cs
{
CRITICAL_SECTION cs;
} SDL_mutex_cs;
/* vi: set ts=4 sw=4 expandtab: */