Pointer as bool (libsdl-org#7214)

src/thread/generic/SDL_syscond.c

@@ -92,7 +92,7 @@ void SDL_DestroyCondition_generic(SDL_Condition *_cond)
 int SDL_SignalCondition_generic(SDL_Condition *_cond)
 {
     SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
-    if (cond == NULL) {
+    if (!cond) {
         return SDL_InvalidParamError("cond");
     }
 
@@ -116,7 +116,7 @@ int SDL_SignalCondition_generic(SDL_Condition *_cond)
 int SDL_BroadcastCondition_generic(SDL_Condition *_cond)
 {
     SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
-    if (cond == NULL) {
+    if (!cond) {
         return SDL_InvalidParamError("cond");
     }
 
@@ -172,7 +172,7 @@ int SDL_WaitConditionTimeoutNS_generic(SDL_Condition *_cond, SDL_Mutex *mutex, S
     SDL_cond_generic *cond = (SDL_cond_generic *)_cond;
     int retval;
 
-    if (cond == NULL) {
+    if (!cond) {
         return SDL_InvalidParamError("cond");
     }
 

src/thread/generic/SDL_sysmutex.c

@@ -87,7 +87,7 @@ int SDL_TryLockMutex(SDL_Mutex *mutex)
 {
     int retval = 0;
 #ifndef SDL_THREADS_DISABLED
-    if (mutex != NULL) {
+    if (mutex) {
         SDL_threadID this_thread = SDL_ThreadID();
         if (mutex->owner == this_thread) {
             ++mutex->recursive;

src/thread/generic/SDL_syssem.c

@@ -66,7 +66,7 @@ SDL_Semaphore *SDL_CreateSemaphore(Uint32 initial_value)
     SDL_Semaphore *sem;
 
     sem = (SDL_Semaphore *)SDL_malloc(sizeof(*sem));
-    if (sem == NULL) {
+    if (!sem) {
         SDL_OutOfMemory();
         return NULL;
     }
@@ -108,7 +108,7 @@ int SDL_WaitSemaphoreTimeoutNS(SDL_Semaphore *sem, Sint64 timeoutNS)
 {
     int retval;
 
-    if (sem == NULL) {
+    if (!sem) {
         return SDL_InvalidParamError("sem");
     }
 
@@ -156,7 +156,7 @@ Uint32 SDL_GetSemaphoreValue(SDL_Semaphore *sem)
 
 int SDL_PostSemaphore(SDL_Semaphore *sem)
 {
-    if (sem == NULL) {
+    if (!sem) {
         return SDL_InvalidParamError("sem");
     }