Pointer as bool (libsdl-org#7214)

VisualC-GDK/tests/testgdk/src/testgdk.cpp

@@ -385,7 +385,7 @@ main(int argc, char *argv[])
 
     /* Initialize test framework */
     state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO | SDL_INIT_AUDIO);
-    if (state == NULL) {
+    if (!state) {
         return 1;
     }
 
@@ -448,7 +448,7 @@ main(int argc, char *argv[])
     /* Create the windows, initialize the renderers, and load the textures */
     sprites =
         (SDL_Texture **) SDL_malloc(state->num_windows * sizeof(*sprites));
-    if (sprites == NULL) {
+    if (!sprites) {
         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Out of memory!\n");
         quit(2);
     }
@@ -463,7 +463,7 @@ main(int argc, char *argv[])
 
     soundname = GetResourceFilename(argc > 1 ? argv[1] : NULL, "sample.wav");
 
-    if (soundname == NULL) {
+    if (!soundname) {
         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "%s\n", SDL_GetError());
         quit(1);
     }

cmake/test/main_gui.c

@@ -10,7 +10,7 @@ int main(int argc, char *argv[])
         return 1;
     }
     window = SDL_CreateWindow("Hello SDL", 640, 480, 0);
-    if (window == NULL) {
+    if (!window) {
         SDL_Log("could not create window: %s\n", SDL_GetError());
         return 1;
     }

src/SDL.c

@@ -557,7 +557,7 @@ int SDL_GetVersion(SDL_version *ver)
     static SDL_bool check_hint = SDL_TRUE;
     static SDL_bool legacy_version = SDL_FALSE;
 
-    if (ver == NULL) {
+    if (!ver) {
         return SDL_InvalidParamError("ver");
     }
 

src/SDL_assert.c

@@ -106,11 +106,11 @@ static void SDL_GenerateAssertionReport(void)
     const SDL_AssertData *item = triggered_assertions;
 
     /* only do this if the app hasn't assigned an assertion handler. */
-    if ((item != NULL) && (assertion_handler != SDL_PromptAssertion)) {
+    if ((item) && (assertion_handler != SDL_PromptAssertion)) {
         debug_print("\n\nSDL assertion report.\n");
         debug_print("All SDL assertions between last init/quit:\n\n");
 
-        while (item != NULL) {
+        while (item) {
             debug_print(
                 "'%s'\n"
                 "    * %s (%s:%d)\n"
@@ -198,7 +198,7 @@ static SDL_AssertState SDLCALL SDL_PromptAssertion(const SDL_AssertData *data, v
 
     /* let env. variable override, so unit tests won't block in a GUI. */
     envr = SDL_getenv("SDL_ASSERT");
-    if (envr != NULL) {
+    if (envr) {
         if (message != stack_buf) {
             SDL_free(message);
         }
@@ -334,9 +334,9 @@ SDL_AssertState SDL_ReportAssertion(SDL_AssertData *data, const char *func, cons
 #ifndef SDL_THREADS_DISABLED
     static SDL_SpinLock spinlock = 0;
     SDL_AtomicLock(&spinlock);
-    if (assertion_mutex == NULL) { /* never called SDL_Init()? */
+    if (!assertion_mutex) { /* never called SDL_Init()? */
         assertion_mutex = SDL_CreateMutex();
-        if (assertion_mutex == NULL) {
+        if (!assertion_mutex) {
             SDL_AtomicUnlock(&spinlock);
             return SDL_ASSERTION_IGNORE; /* oh well, I guess. */
         }
@@ -401,7 +401,7 @@ void SDL_AssertionsQuit(void)
 #if SDL_ASSERT_LEVEL > 0
     SDL_GenerateAssertionReport();
 #ifndef SDL_THREADS_DISABLED
-    if (assertion_mutex != NULL) {
+    if (assertion_mutex) {
         SDL_DestroyMutex(assertion_mutex);
         assertion_mutex = NULL;
     }
@@ -429,7 +429,7 @@ void SDL_ResetAssertionReport(void)
 {
     SDL_AssertData *next = NULL;
     SDL_AssertData *item;
-    for (item = triggered_assertions; item != NULL; item = next) {
+    for (item = triggered_assertions; item; item = next) {
         next = (SDL_AssertData *)item->next;
         item->always_ignore = SDL_FALSE;
         item->trigger_count = 0;
@@ -446,7 +446,7 @@ SDL_AssertionHandler SDL_GetDefaultAssertionHandler(void)
 
 SDL_AssertionHandler SDL_GetAssertionHandler(void **userdata)
 {
-    if (userdata != NULL) {
+    if (userdata) {
         *userdata = assertion_userdata;
     }
     return assertion_handler;

src/SDL_error.c

@@ -27,7 +27,7 @@
 int SDL_SetError(SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
 {
     /* Ignore call if invalid format pointer was passed */
-    if (fmt != NULL) {
+    if (fmt) {
         va_list ap;
         int result;
         SDL_error *error = SDL_GetErrBuf();

src/SDL_guid.c

@@ -26,7 +26,7 @@ int SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int cbGUID)
     static const char k_rgchHexToASCII[] = "0123456789abcdef";
     int i;
 
-    if (pszGUID == NULL) {
+    if (!pszGUID) {
         return SDL_InvalidParamError("pszGUID");
     }
     if (cbGUID <= 0) {

src/SDL_hashtable.c

@@ -53,13 +53,13 @@ SDL_HashTable *SDL_CreateHashTable(void *data, const Uint32 num_buckets, const S
     }
 
     table = (SDL_HashTable *) SDL_calloc(1, sizeof (SDL_HashTable));
-    if (table == NULL) {
+    if (!table) {
         SDL_OutOfMemory();
         return NULL;
     }
 
     table->table = (SDL_HashItem **) SDL_calloc(num_buckets, sizeof (SDL_HashItem *));
-    if (table->table == NULL) {
+    if (!table->table) {
         SDL_free(table);
         SDL_OutOfMemory();
         return NULL;
@@ -91,7 +91,7 @@ SDL_bool SDL_InsertIntoHashTable(SDL_HashTable *table, const void *key, const vo
 
     // !!! FIXME: grow and rehash table if it gets too saturated.
     item = (SDL_HashItem *) SDL_malloc(sizeof (SDL_HashItem));
-    if (item == NULL) {
+    if (!item) {
         SDL_OutOfMemory();
         return SDL_FALSE;
     }
@@ -110,9 +110,9 @@ SDL_bool SDL_FindInHashTable(const SDL_HashTable *table, const void *key, const
     void *data = table->data;
     SDL_HashItem *i;
 
-    for (i = table->table[hash]; i != NULL; i = i->next) {
+    for (i = table->table[hash]; i; i = i->next) {
         if (table->keymatch(key, i->key, data)) {
-            if (_value != NULL) {
+            if (_value) {
                 *_value = i->value;
             }
             return SDL_TRUE;
@@ -129,9 +129,9 @@ SDL_bool SDL_RemoveFromHashTable(SDL_HashTable *table, const void *key)
     SDL_HashItem *prev = NULL;
     void *data = table->data;
 
-    for (item = table->table[hash]; item != NULL; item = item->next) {
+    for (item = table->table[hash]; item; item = item->next) {
         if (table->keymatch(key, item->key, data)) {
-            if (prev != NULL) {
+            if (prev) {
                 prev->next = item->next;
             } else {
                 table->table[hash] = item->next;
@@ -152,7 +152,7 @@ SDL_bool SDL_IterateHashTableKey(const SDL_HashTable *table, const void *key, co
 {
     SDL_HashItem *item = *iter ? ((SDL_HashItem *) *iter)->next : table->table[calc_hash(table, key)];
 
-    while (item != NULL) {
+    while (item) {
         if (table->keymatch(key, item->key, table->data)) {
             *_value = item->value;
             *iter = item;
@@ -172,10 +172,10 @@ SDL_bool SDL_IterateHashTable(const SDL_HashTable *table, const void **_key, con
     SDL_HashItem *item = (SDL_HashItem *) *iter;
     Uint32 idx = 0;
 
-    if (item != NULL) {
+    if (item) {
         const SDL_HashItem *orig = item;
         item = item->next;
-        if (item == NULL) {
+        if (!item) {
             idx = calc_hash(table, orig->key) + 1;  // !!! FIXME: we probably shouldn't rehash each time.
         }
     }
@@ -184,7 +184,7 @@ SDL_bool SDL_IterateHashTable(const SDL_HashTable *table, const void **_key, con
         item = table->table[idx++];  // skip empty buckets...
     }
 
-    if (item == NULL) {  // no more matches?
+    if (!item) {  // no more matches?
         *_key = NULL;
         *iter = NULL;
         return SDL_FALSE;
@@ -199,12 +199,12 @@ SDL_bool SDL_IterateHashTable(const SDL_HashTable *table, const void **_key, con
 
 SDL_bool SDL_HashTableEmpty(SDL_HashTable *table)
 {
-    if (table != NULL) {
+    if (table) {
         Uint32 i;
 
         for (i = 0; i < table->table_len; i++) {
             SDL_HashItem *item = table->table[i];
-            if (item != NULL) {
+            if (item) {
                 return SDL_FALSE;
             }
         }
@@ -214,13 +214,13 @@ SDL_bool SDL_HashTableEmpty(SDL_HashTable *table)
 
 void SDL_DestroyHashTable(SDL_HashTable *table)
 {
-    if (table != NULL) {
+    if (table) {
         void *data = table->data;
         Uint32 i;
 
         for (i = 0; i < table->table_len; i++) {
             SDL_HashItem *item = table->table[i];
-            while (item != NULL) {
+            while (item) {
                 SDL_HashItem *next = item->next;
                 table->nuke(item->key, item->value, data);
                 SDL_free(item);

src/SDL_hints.c

@@ -49,7 +49,7 @@ SDL_bool SDL_SetHintWithPriority(const char *name, const char *value, SDL_HintPr
     SDL_Hint *hint;
     SDL_HintWatch *entry;
 
-    if (name == NULL) {
+    if (!name) {
         return SDL_FALSE;
     }
 
@@ -64,7 +64,7 @@ SDL_bool SDL_SetHintWithPriority(const char *name, const char *value, SDL_HintPr
                 return SDL_FALSE;
             }
             if (hint->value != value &&
-                (value == NULL || !hint->value || SDL_strcmp(hint->value, value) != 0)) {
+                (!value || !hint->value || SDL_strcmp(hint->value, value) != 0)) {
                 char *old_value = hint->value;
 
                 hint->value = value ? SDL_strdup(value) : NULL;
@@ -85,7 +85,7 @@ SDL_bool SDL_SetHintWithPriority(const char *name, const char *value, SDL_HintPr
 
     /* Couldn't find the hint, add a new one */
     hint = (SDL_Hint *)SDL_malloc(sizeof(*hint));
-    if (hint == NULL) {
+    if (!hint) {
         return SDL_FALSE;
     }
     hint->name = SDL_strdup(name);
@@ -103,16 +103,16 @@ SDL_bool SDL_ResetHint(const char *name)
     SDL_Hint *hint;
     SDL_HintWatch *entry;
 
-    if (name == NULL) {
+    if (!name) {
         return SDL_FALSE;
     }
 
     env = SDL_getenv(name);
     for (hint = SDL_hints; hint; hint = hint->next) {
         if (SDL_strcmp(name, hint->name) == 0) {
-            if ((env == NULL && hint->value != NULL) ||
-                (env != NULL && hint->value == NULL) ||
-                (env != NULL && SDL_strcmp(env, hint->value) != 0)) {
+            if ((!env && hint->value) ||
+                (env && !hint->value) ||
+                (env && SDL_strcmp(env, hint->value) != 0)) {
                 for (entry = hint->callbacks; entry;) {
                     /* Save the next entry in case this one is deleted */
                     SDL_HintWatch *next = entry->next;
@@ -137,9 +137,9 @@ void SDL_ResetHints(void)
 
     for (hint = SDL_hints; hint; hint = hint->next) {
         env = SDL_getenv(hint->name);
-        if ((env == NULL && hint->value != NULL) ||
-            (env != NULL && hint->value == NULL) ||
-            (env != NULL && SDL_strcmp(env, hint->value) != 0)) {
+        if ((!env && hint->value) ||
+            (env && !hint->value) ||
+            (env && SDL_strcmp(env, hint->value) != 0)) {
             for (entry = hint->callbacks; entry;) {
                 /* Save the next entry in case this one is deleted */
                 SDL_HintWatch *next = entry->next;
@@ -166,7 +166,7 @@ const char *SDL_GetHint(const char *name)
     env = SDL_getenv(name);
     for (hint = SDL_hints; hint; hint = hint->next) {
         if (SDL_strcmp(name, hint->name) == 0) {
-            if (env == NULL || hint->priority == SDL_HINT_OVERRIDE) {
+            if (!env || hint->priority == SDL_HINT_OVERRIDE) {
                 return hint->value;
             }
             break;
@@ -177,7 +177,7 @@ const char *SDL_GetHint(const char *name)
 
 int SDL_GetStringInteger(const char *value, int default_value)
 {
-    if (value == NULL || !*value) {
+    if (!value || !*value) {
         return default_value;
     }
     if (*value == '0' || SDL_strcasecmp(value, "false") == 0) {
@@ -194,7 +194,7 @@ int SDL_GetStringInteger(const char *value, int default_value)
 
 SDL_bool SDL_GetStringBoolean(const char *value, SDL_bool default_value)
 {
-    if (value == NULL || !*value) {
+    if (!value || !*value) {
         return default_value;
     }
     if (*value == '0' || SDL_strcasecmp(value, "false") == 0) {
@@ -215,7 +215,7 @@ int SDL_AddHintCallback(const char *name, SDL_HintCallback callback, void *userd
     SDL_HintWatch *entry;
     const char *value;
 
-    if (name == NULL || !*name) {
+    if (!name || !*name) {
         return SDL_InvalidParamError("name");
     }
     if (!callback) {
@@ -225,7 +225,7 @@ int SDL_AddHintCallback(const char *name, SDL_HintCallback callback, void *userd
     SDL_DelHintCallback(name, callback, userdata);
 
     entry = (SDL_HintWatch *)SDL_malloc(sizeof(*entry));
-    if (entry == NULL) {
+    if (!entry) {
         return SDL_OutOfMemory();
     }
     entry->callback = callback;
@@ -236,10 +236,10 @@ int SDL_AddHintCallback(const char *name, SDL_HintCallback callback, void *userd
             break;
         }
     }
-    if (hint == NULL) {
+    if (!hint) {
         /* Need to add a hint entry for this watcher */
         hint = (SDL_Hint *)SDL_malloc(sizeof(*hint));
-        if (hint == NULL) {
+        if (!hint) {
             SDL_free(entry);
             return SDL_OutOfMemory();
         }

src/SDL_list.c

@@ -27,7 +27,7 @@ int SDL_ListAdd(SDL_ListNode **head, void *ent)
 {
     SDL_ListNode *node = SDL_malloc(sizeof(*node));
 
-    if (node == NULL) {
+    if (!node) {
         return SDL_OutOfMemory();
     }
 
@@ -43,7 +43,7 @@ void SDL_ListPop(SDL_ListNode **head, void **ent)
     SDL_ListNode **ptr = head;
 
     /* Invalid or empty */
-    if (head == NULL || *head == NULL) {
+    if (!head || !*head) {
         return;
     }
 

src/SDL_log.c

@@ -112,7 +112,7 @@ static int SDL_android_priority[SDL_NUM_LOG_PRIORITIES] = {
 
 void SDL_InitLog(void)
 {
-    if (log_function_mutex == NULL) {
+    if (!log_function_mutex) {
         /* if this fails we'll try to continue without it. */
         log_function_mutex = SDL_CreateMutex();
     }
@@ -305,7 +305,7 @@ void SDL_LogMessageV(int category, SDL_LogPriority priority, const char *fmt, va
         return;
     }
 
-    if (log_function_mutex == NULL) {
+    if (!log_function_mutex) {
         /* this mutex creation can race if you log from two threads at startup. You should have called SDL_Init first! */
         log_function_mutex = SDL_CreateMutex();
     }
@@ -323,7 +323,7 @@ void SDL_LogMessageV(int category, SDL_LogPriority priority, const char *fmt, va
     if (len >= sizeof(stack_buf) && SDL_size_add_overflow(len, 1, &len_plus_term) == 0) {
         /* Allocate exactly what we need, including the zero-terminator */
         message = (char *)SDL_malloc(len_plus_term);
-        if (message == NULL) {
+        if (!message) {
             return;
         }
         va_copy(aq, ap);
@@ -459,7 +459,7 @@ static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority
     {
         FILE *pFile;
         pFile = fopen("SDL_Log.txt", "a");
-        if (pFile != NULL) {
+        if (pFile) {
             (void)fprintf(pFile, "%s: %s\n", SDL_priority_prefixes[priority], message);
             (void)fclose(pFile);
         }
@@ -468,7 +468,7 @@ static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority
     {
         FILE *pFile;
         pFile = fopen("ux0:/data/SDL_Log.txt", "a");
-        if (pFile != NULL) {
+        if (pFile) {
             (void)fprintf(pFile, "%s: %s\n", SDL_priority_prefixes[priority], message);
             (void)fclose(pFile);
         }
@@ -477,7 +477,7 @@ static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority
     {
         FILE *pFile;
         pFile = fopen("sdmc:/3ds/SDL_Log.txt", "a");
-        if (pFile != NULL) {
+        if (pFile) {
             (void)fprintf(pFile, "%s: %s\n", SDL_priority_prefixes[priority], message);
             (void)fclose(pFile);
         }

src/atomic/SDL_spinlock.c

@@ -63,7 +63,7 @@ SDL_bool SDL_AtomicTryLock(SDL_SpinLock *lock)
     /* Terrible terrible damage */
     static SDL_Mutex *_spinlock_mutex;
 
-    if (_spinlock_mutex == NULL) {
+    if (!_spinlock_mutex) {
         /* Race condition on first lock... */
         _spinlock_mutex = SDL_CreateMutex();
     }

src/audio/SDL_audio.c

@@ -139,7 +139,7 @@ static int GetDefaultSampleFramesFromFreq(const int freq)
 
 void OnAudioStreamCreated(SDL_AudioStream *stream)
 {
-    SDL_assert(stream != NULL);
+    SDL_assert(stream);
 
     // NOTE that you can create an audio stream without initializing the audio subsystem,
     //  but it will not be automatically destroyed during a later call to SDL_Quit!
@@ -159,7 +159,7 @@ void OnAudioStreamCreated(SDL_AudioStream *stream)
 
 void OnAudioStreamDestroy(SDL_AudioStream *stream)
 {
-    SDL_assert(stream != NULL);
+    SDL_assert(stream);
 
     // NOTE that you can create an audio stream without initializing the audio subsystem,
     //  but it will not be automatically destroyed during a later call to SDL_Quit!
@@ -207,8 +207,8 @@ static void UpdateAudioStreamFormatsPhysical(SDL_AudioDevice *device)
             spec.format = SDL_AUDIO_F32;  // mixing and postbuf operates in float32 format.
         }
 
-        for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev != NULL; logdev = logdev->next) {
-            for (SDL_AudioStream *stream = logdev->bound_streams; stream != NULL; stream = stream->next_binding) {
+        for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev; logdev = logdev->next) {
+            for (SDL_AudioStream *stream = logdev->bound_streams; stream; stream = stream->next_binding) {
                 // set the proper end of the stream to the device's format.
                 // SDL_SetAudioStreamFormat does a ton of validation just to memcpy an audiospec.
                 SDL_LockMutex(stream->lock);
@@ -441,7 +441,7 @@ static void DestroyLogicalAudioDevice(SDL_LogicalAudioDevice *logdev)
 
     // unbind any still-bound streams...
     SDL_AudioStream *next;
-    for (SDL_AudioStream *stream = logdev->bound_streams; stream != NULL; stream = next) {
+    for (SDL_AudioStream *stream = logdev->bound_streams; stream; stream = next) {
         SDL_LockMutex(stream->lock);
         next = stream->next_binding;
         stream->next_binding = NULL;
@@ -463,7 +463,7 @@ static void DestroyPhysicalAudioDevice(SDL_AudioDevice *device)
 
     // Destroy any logical devices that still exist...
     SDL_LockMutex(device->lock);  // don't use ObtainPhysicalAudioDeviceObj because we don't want to change refcounts while destroying.
-    while (device->logical_devices != NULL) {
+    while (device->logical_devices) {
         DestroyLogicalAudioDevice(device->logical_devices);
     }
     SDL_UnlockMutex(device->lock);  // don't use ReleaseAudioDevice because we don't want to change refcounts while destroying.
@@ -500,7 +500,7 @@ void RefPhysicalAudioDevice(SDL_AudioDevice *device)
 
 static SDL_AudioDevice *CreatePhysicalAudioDevice(const char *name, SDL_bool iscapture, const SDL_AudioSpec *spec, void *handle, SDL_AtomicInt *device_count)
 {
-    SDL_assert(name != NULL);
+    SDL_assert(name);
 
     SDL_LockRWLockForReading(current_audio.device_hash_lock);
     const int shutting_down = SDL_AtomicGet(&current_audio.shutting_down);
@@ -593,8 +593,8 @@ SDL_AudioDevice *SDL_AddAudioDevice(const SDL_bool iscapture, const char *name,
             p->devid = device->instance_id;
             p->next = NULL;
             SDL_LockRWLockForWriting(current_audio.device_hash_lock);
-            SDL_assert(current_audio.pending_events_tail != NULL);
-            SDL_assert(current_audio.pending_events_tail->next == NULL);
+            SDL_assert(current_audio.pending_events_tail);
+            SDL_assert(!current_audio.pending_events_tail->next);
             current_audio.pending_events_tail->next = p;
             current_audio.pending_events_tail = p;
             SDL_UnlockRWLock(current_audio.device_hash_lock);
@@ -642,7 +642,7 @@ void SDL_AudioDeviceDisconnected(SDL_AudioDevice *device)
         // on default devices, dump any logical devices that explicitly opened this device. Things that opened the system default can stay.
         // on non-default devices, dump everything.
         // (by "dump" we mean send a REMOVED event; the zombie will keep consuming audio data for these logical devices until explicitly closed.)
-        for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev != NULL; logdev = logdev->next) {
+        for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev; logdev = logdev->next) {
             if (!is_default_device || !logdev->opened_as_default) {  // if opened as a default, leave it on the zombie device for later migration.
                 SDL_PendingAudioDeviceEvent *p = (SDL_PendingAudioDeviceEvent *) SDL_malloc(sizeof (SDL_PendingAudioDeviceEvent));
                 if (p) {  // if this failed, no event for you, but you have deeper problems anyhow.
@@ -670,8 +670,8 @@ void SDL_AudioDeviceDisconnected(SDL_AudioDevice *device)
     if (first_disconnect) {
         if (pending.next) {  // NULL if event is disabled or disaster struck.
             SDL_LockRWLockForWriting(current_audio.device_hash_lock);
-            SDL_assert(current_audio.pending_events_tail != NULL);
-            SDL_assert(current_audio.pending_events_tail->next == NULL);
+            SDL_assert(current_audio.pending_events_tail);
+            SDL_assert(!current_audio.pending_events_tail->next);
             current_audio.pending_events_tail->next = pending.next;
             current_audio.pending_events_tail = pending_tail;
             SDL_UnlockRWLock(current_audio.device_hash_lock);
@@ -817,26 +817,26 @@ int SDL_InitAudio(const char *driver_name)
     }
 
     // Select the proper audio driver
-    if (driver_name == NULL) {
+    if (!driver_name) {
         driver_name = SDL_GetHint(SDL_HINT_AUDIO_DRIVER);
     }
 
     SDL_bool initialized = SDL_FALSE;
     SDL_bool tried_to_init = SDL_FALSE;
 
-    if (driver_name != NULL && *driver_name != 0) {
+    if (driver_name && *driver_name != 0) {
         char *driver_name_copy = SDL_strdup(driver_name);
         const char *driver_attempt = driver_name_copy;
 
-        if (driver_name_copy == NULL) {
+        if (!driver_name_copy) {
             SDL_DestroyRWLock(device_hash_lock);
             SDL_DestroyHashTable(device_hash);
             return SDL_OutOfMemory();
         }
 
-        while (driver_attempt != NULL && *driver_attempt != 0 && !initialized) {
+        while (driver_attempt && *driver_attempt != 0 && !initialized) {
             char *driver_attempt_end = SDL_strchr(driver_attempt, ',');
-            if (driver_attempt_end != NULL) {
+            if (driver_attempt_end) {
                 *driver_attempt_end = '\0';
             }
 
@@ -863,7 +863,7 @@ int SDL_InitAudio(const char *driver_name)
                 }
             }
 
-            driver_attempt = (driver_attempt_end != NULL) ? (driver_attempt_end + 1) : NULL;
+            driver_attempt = (driver_attempt_end) ? (driver_attempt_end + 1) : NULL;
         }
 
         SDL_free(driver_name_copy);
@@ -940,7 +940,7 @@ void SDL_QuitAudio(void)
     current_audio.impl.DeinitializeStart();
 
     // Destroy any audio streams that still exist...
-    while (current_audio.existing_streams != NULL) {
+    while (current_audio.existing_streams) {
         SDL_DestroyAudioStream(current_audio.existing_streams);
     }
 
@@ -955,7 +955,7 @@ void SDL_QuitAudio(void)
     SDL_UnlockRWLock(current_audio.device_hash_lock);
 
     SDL_PendingAudioDeviceEvent *pending_next = NULL;
-    for (SDL_PendingAudioDeviceEvent *i = pending_events; i != NULL; i = pending_next) {
+    for (SDL_PendingAudioDeviceEvent *i = pending_events; i; i = pending_next) {
         pending_next = i->next;
         SDL_free(i);
     }
@@ -1053,7 +1053,7 @@ SDL_bool SDL_OutputAudioThreadIterate(SDL_AudioDevice *device)
 
             SDL_memset(final_mix_buffer, '\0', work_buffer_size);  // start with silence.
 
-            for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev != NULL; logdev = logdev->next) {
+            for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev; logdev = logdev->next) {
                 if (SDL_AtomicGet(&logdev->paused)) {
                     continue;  // paused? Skip this logical device.
                 }
@@ -1065,7 +1065,7 @@ SDL_bool SDL_OutputAudioThreadIterate(SDL_AudioDevice *device)
                     SDL_memset(mix_buffer, '\0', work_buffer_size);  // start with silence.
                 }
 
-                for (SDL_AudioStream *stream = logdev->bound_streams; stream != NULL; stream = stream->next_binding) {
+                for (SDL_AudioStream *stream = logdev->bound_streams; stream; stream = stream->next_binding) {
                     // We should have updated this elsewhere if the format changed!
                     SDL_assert(AUDIO_SPECS_EQUAL(stream->dst_spec, outspec));
 
@@ -1127,7 +1127,7 @@ void SDL_OutputAudioThreadShutdown(SDL_AudioDevice *device)
 static int SDLCALL OutputAudioThread(void *devicep)  // thread entry point
 {
     SDL_AudioDevice *device = (SDL_AudioDevice *)devicep;
-    SDL_assert(device != NULL);
+    SDL_assert(device);
     SDL_assert(!device->iscapture);
     SDL_OutputAudioThreadSetup(device);
 
@@ -1164,7 +1164,7 @@ SDL_bool SDL_CaptureAudioThreadIterate(SDL_AudioDevice *device)
 
     SDL_bool failed = SDL_FALSE;
 
-    if (device->logical_devices == NULL) {
+    if (!device->logical_devices) {
         device->FlushCapture(device); // nothing wants data, dump anything pending.
     } else {
         // this SHOULD NOT BLOCK, as we are holding a lock right now. Block in WaitCaptureDevice!
@@ -1172,7 +1172,7 @@ SDL_bool SDL_CaptureAudioThreadIterate(SDL_AudioDevice *device)
         if (br < 0) {  // uhoh, device failed for some reason!
             failed = SDL_TRUE;
         } else if (br > 0) {  // queue the new data to each bound stream.
-            for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev != NULL; logdev = logdev->next) {
+            for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev; logdev = logdev->next) {
                 if (SDL_AtomicGet(&logdev->paused)) {
                     continue;  // paused? Skip this logical device.
                 }
@@ -1193,7 +1193,7 @@ SDL_bool SDL_CaptureAudioThreadIterate(SDL_AudioDevice *device)
                     logdev->postmix(logdev->postmix_userdata, &outspec, device->postmix_buffer, br);
                 }
 
-                for (SDL_AudioStream *stream = logdev->bound_streams; stream != NULL; stream = stream->next_binding) {
+                for (SDL_AudioStream *stream = logdev->bound_streams; stream; stream = stream->next_binding) {
                     // We should have updated this elsewhere if the format changed!
                     SDL_assert(stream->src_spec.format == (logdev->postmix ? SDL_AUDIO_F32 : device->spec.format));
                     SDL_assert(stream->src_spec.channels == device->spec.channels);
@@ -1233,7 +1233,7 @@ void SDL_CaptureAudioThreadShutdown(SDL_AudioDevice *device)
 static int SDLCALL CaptureAudioThread(void *devicep)  // thread entry point
 {
     SDL_AudioDevice *device = (SDL_AudioDevice *)devicep;
-    SDL_assert(device != NULL);
+    SDL_assert(device);
     SDL_assert(device->iscapture);
     SDL_CaptureAudioThreadSetup(device);
 
@@ -1261,7 +1261,7 @@ static SDL_AudioDeviceID *GetAudioDevices(int *reqcount, SDL_bool iscapture)
     int num_devices = SDL_AtomicGet(iscapture ? &current_audio.capture_device_count : &current_audio.output_device_count);
     if (num_devices > 0) {
         retval = (SDL_AudioDeviceID *) SDL_malloc((num_devices + 1) * sizeof (SDL_AudioDeviceID));
-        if (retval == NULL) {
+        if (!retval) {
             num_devices = 0;
             SDL_OutOfMemory();
         } else {
@@ -1287,7 +1287,7 @@ static SDL_AudioDeviceID *GetAudioDevices(int *reqcount, SDL_bool iscapture)
     }
     SDL_UnlockRWLock(current_audio.device_hash_lock);
 
-    if (reqcount != NULL) {
+    if (reqcount) {
         *reqcount = num_devices;
     }
 
@@ -1384,7 +1384,7 @@ int SDL_GetAudioDeviceFormat(SDL_AudioDeviceID devid, SDL_AudioSpec *spec, int *
 static void ClosePhysicalAudioDevice(SDL_AudioDevice *device)
 {
     SDL_AtomicSet(&device->shutdown, 1);
-    if (device->thread != NULL) {
+    if (device->thread) {
         SDL_WaitThread(device->thread, NULL);
         device->thread = NULL;
     }
@@ -1417,7 +1417,7 @@ void SDL_CloseAudioDevice(SDL_AudioDeviceID devid)
     SDL_LogicalAudioDevice *logdev = ObtainLogicalAudioDevice(devid, &device);
     if (logdev) {
         DestroyLogicalAudioDevice(logdev);
-        close_physical = (device->logical_devices == NULL); // no more logical devices? Close the physical device, too.
+        close_physical = (!device->logical_devices); // no more logical devices? Close the physical device, too.
     }
 
     // !!! FIXME: we _need_ to release this lock, but doing so can cause a race condition if someone opens a device while we're closing it.
@@ -1458,7 +1458,7 @@ static void PrepareAudioFormat(SDL_bool iscapture, SDL_AudioSpec *spec)
         spec->freq = iscapture ? DEFAULT_AUDIO_CAPTURE_FREQUENCY : DEFAULT_AUDIO_OUTPUT_FREQUENCY;
 
         const char *env = SDL_getenv("SDL_AUDIO_FREQUENCY");  // !!! FIXME: should be a hint?
-        if (env != NULL) {
+        if (env) {
             const int val = SDL_atoi(env);
             if (val > 0) {
                 spec->freq = val;
@@ -1469,7 +1469,7 @@ static void PrepareAudioFormat(SDL_bool iscapture, SDL_AudioSpec *spec)
     if (spec->channels == 0) {
         spec->channels = iscapture ? DEFAULT_AUDIO_CAPTURE_CHANNELS : DEFAULT_AUDIO_OUTPUT_CHANNELS;;
         const char *env = SDL_getenv("SDL_AUDIO_CHANNELS");
-        if (env != NULL) {
+        if (env) {
             const int val = SDL_atoi(env);
             if (val > 0) {
                 spec->channels = val;
@@ -1502,7 +1502,7 @@ char *SDL_GetAudioThreadName(SDL_AudioDevice *device, char *buf, size_t buflen)
 static int OpenPhysicalAudioDevice(SDL_AudioDevice *device, const SDL_AudioSpec *inspec)
 {
     SDL_assert(!device->currently_opened);
-    SDL_assert(device->logical_devices == NULL);
+    SDL_assert(!device->logical_devices);
 
     // Just pretend to open a zombie device. It can still collect logical devices on a default device under the assumption they will all migrate when the default device is officially changed.
     if (SDL_AtomicGet(&device->zombie)) {
@@ -1541,14 +1541,14 @@ static int OpenPhysicalAudioDevice(SDL_AudioDevice *device, const SDL_AudioSpec
 
     // Allocate a scratch audio buffer
     device->work_buffer = (Uint8 *)SDL_aligned_alloc(SDL_SIMDGetAlignment(), device->work_buffer_size);
-    if (device->work_buffer == NULL) {
+    if (!device->work_buffer) {
         ClosePhysicalAudioDevice(device);
         return SDL_OutOfMemory();
     }
 
     if (device->spec.format != SDL_AUDIO_F32) {
         device->mix_buffer = (Uint8 *)SDL_aligned_alloc(SDL_SIMDGetAlignment(), device->work_buffer_size);
-        if (device->mix_buffer == NULL) {
+        if (!device->mix_buffer) {
             ClosePhysicalAudioDevice(device);
             return SDL_OutOfMemory();
         }
@@ -1561,7 +1561,7 @@ static int OpenPhysicalAudioDevice(SDL_AudioDevice *device, const SDL_AudioSpec
         SDL_GetAudioThreadName(device, threadname, sizeof (threadname));
         device->thread = SDL_CreateThreadInternal(device->iscapture ? CaptureAudioThread : OutputAudioThread, threadname, stacksize, device);
 
-        if (device->thread == NULL) {
+        if (!device->thread) {
             ClosePhysicalAudioDevice(device);
             return SDL_SetError("Couldn't create audio thread");
         }
@@ -1672,7 +1672,7 @@ int SDL_SetAudioPostmixCallback(SDL_AudioDeviceID devid, SDL_AudioPostmixCallbac
     if (logdev) {
         if (callback && !device->postmix_buffer) {
             device->postmix_buffer = (float *)SDL_aligned_alloc(SDL_SIMDGetAlignment(), device->work_buffer_size);
-            if (device->postmix_buffer == NULL) {
+            if (!device->postmix_buffer) {
                 retval = SDL_OutOfMemory();
             }
         }
@@ -1682,7 +1682,7 @@ int SDL_SetAudioPostmixCallback(SDL_AudioDeviceID devid, SDL_AudioPostmixCallbac
             logdev->postmix_userdata = userdata;
 
             if (device->iscapture) {
-                for (SDL_AudioStream *stream = logdev->bound_streams; stream != NULL; stream = stream->next_binding) {
+                for (SDL_AudioStream *stream = logdev->bound_streams; stream; stream = stream->next_binding) {
                     // set the proper end of the stream to the device's format.
                     // SDL_SetAudioStreamFormat does a ton of validation just to memcpy an audiospec.
                     SDL_LockMutex(stream->lock);
@@ -1709,7 +1709,7 @@ int SDL_BindAudioStreams(SDL_AudioDeviceID devid, SDL_AudioStream **streams, int
         return 0;  // nothing to do
     } else if (num_streams < 0) {
         return SDL_InvalidParamError("num_streams");
-    } else if (streams == NULL) {
+    } else if (!streams) {
         return SDL_InvalidParamError("streams");
     } else if (!islogical) {
         return SDL_SetError("Audio streams are bound to device ids from SDL_OpenAudioDevice, not raw physical devices");
@@ -1726,16 +1726,16 @@ int SDL_BindAudioStreams(SDL_AudioDeviceID devid, SDL_AudioStream **streams, int
         // !!! FIXME: Actually, why do we allow there to be an invalid format, again?
 
         // make sure start of list is sane.
-        SDL_assert(!logdev->bound_streams || (logdev->bound_streams->prev_binding == NULL));
+        SDL_assert(!logdev->bound_streams || (!logdev->bound_streams->prev_binding));
 
         // lock all the streams upfront, so we can verify they aren't bound elsewhere and add them all in one block, as this is intended to add everything or nothing.
         for (int i = 0; i < num_streams; i++) {
             SDL_AudioStream *stream = streams[i];
-            if (stream == NULL) {
+            if (!stream) {
                 retval = SDL_SetError("Stream #%d is NULL", i);
             } else {
                 SDL_LockMutex(stream->lock);
-                SDL_assert((stream->bound_device == NULL) == ((stream->prev_binding == NULL) || (stream->next_binding == NULL)));
+                SDL_assert((!stream->bound_device) == ((!stream->prev_binding) || (!stream->next_binding)));
                 if (stream->bound_device) {
                     retval = SDL_SetError("Stream #%d is already bound to a device", i);
                 } else if (stream->simplified) {  // You can get here if you closed the device instead of destroying the stream.
@@ -1830,7 +1830,7 @@ void SDL_UnbindAudioStreams(SDL_AudioStream **streams, int num_streams)
         // don't allow unbinding from "simplified" devices (opened with SDL_OpenAudioDeviceStream). Just ignore them.
         if (stream && stream->bound_device && !stream->bound_device->simplified) {
             if (stream->bound_device->bound_streams == stream) {
-                SDL_assert(stream->prev_binding == NULL);
+                SDL_assert(!stream->prev_binding);
                 stream->bound_device->bound_streams = stream->next_binding;
             }
             if (stream->prev_binding) {
@@ -1887,12 +1887,12 @@ SDL_AudioStream *SDL_OpenAudioDeviceStream(SDL_AudioDeviceID devid, const SDL_Au
     SDL_AudioStream *stream = NULL;
     SDL_AudioDevice *device = NULL;
     SDL_LogicalAudioDevice *logdev = ObtainLogicalAudioDevice(logdevid, &device);
-    if (logdev == NULL) { // this shouldn't happen, but just in case.
+    if (!logdev) { // this shouldn't happen, but just in case.
         failed = SDL_TRUE;
     } else {
         SDL_AtomicSet(&logdev->paused, 1);   // start the device paused, to match SDL2.
 
-        SDL_assert(device != NULL);
+        SDL_assert(device);
         const SDL_bool iscapture = device->iscapture;
 
         if (iscapture) {
@@ -1960,7 +1960,7 @@ int SDL_GetSilenceValueForFormat(SDL_AudioFormat format)
 // called internally by backends when the system default device changes.
 void SDL_DefaultAudioDeviceChanged(SDL_AudioDevice *new_default_device)
 {
-    if (new_default_device == NULL) {  // !!! FIXME: what should we do in this case? Maybe all devices are lost, so there _isn't_ a default?
+    if (!new_default_device) {  // !!! FIXME: what should we do in this case? Maybe all devices are lost, so there _isn't_ a default?
         return;  // uhoh.
     }
 
@@ -2007,10 +2007,10 @@ void SDL_DefaultAudioDeviceChanged(SDL_AudioDevice *new_default_device)
         SDL_bool needs_migration = SDL_FALSE;
         SDL_zero(spec);
 
-        for (SDL_LogicalAudioDevice *logdev = current_default_device->logical_devices; logdev != NULL; logdev = logdev->next) {
+        for (SDL_LogicalAudioDevice *logdev = current_default_device->logical_devices; logdev; logdev = logdev->next) {
             if (logdev->opened_as_default) {
                 needs_migration = SDL_TRUE;
-                for (SDL_AudioStream *stream = logdev->bound_streams; stream != NULL; stream = stream->next_binding) {
+                for (SDL_AudioStream *stream = logdev->bound_streams; stream; stream = stream->next_binding) {
                     const SDL_AudioSpec *streamspec = iscapture ? &stream->dst_spec : &stream->src_spec;
                     if (SDL_AUDIO_BITSIZE(streamspec->format) > SDL_AUDIO_BITSIZE(spec.format)) {
                         spec.format = streamspec->format;
@@ -2036,7 +2036,7 @@ void SDL_DefaultAudioDeviceChanged(SDL_AudioDevice *new_default_device)
         if (needs_migration) {
             const SDL_bool spec_changed = !AUDIO_SPECS_EQUAL(current_default_device->spec, new_default_device->spec);
             SDL_LogicalAudioDevice *next = NULL;
-            for (SDL_LogicalAudioDevice *logdev = current_default_device->logical_devices; logdev != NULL; logdev = next) {
+            for (SDL_LogicalAudioDevice *logdev = current_default_device->logical_devices; logdev; logdev = next) {
                 next = logdev->next;
 
                 if (!logdev->opened_as_default) {
@@ -2083,7 +2083,7 @@ void SDL_DefaultAudioDeviceChanged(SDL_AudioDevice *new_default_device)
             UpdateAudioStreamFormatsPhysical(current_default_device);
             UpdateAudioStreamFormatsPhysical(new_default_device);
 
-            if (current_default_device->logical_devices == NULL) {   // nothing left on the current physical device, close it.
+            if (!current_default_device->logical_devices) {   // nothing left on the current physical device, close it.
                 // !!! FIXME: we _need_ to release this lock, but doing so can cause a race condition if someone opens a device while we're closing it.
                 RefPhysicalAudioDevice(current_default_device);  // hold a temp ref for a moment while we release...
                 ReleaseAudioDevice(current_default_device);  // can't hold the lock or the audio thread will deadlock while we WaitThread it.
@@ -2105,8 +2105,8 @@ void SDL_DefaultAudioDeviceChanged(SDL_AudioDevice *new_default_device)
 
     if (pending.next) {
         SDL_LockRWLockForWriting(current_audio.device_hash_lock);
-        SDL_assert(current_audio.pending_events_tail != NULL);
-        SDL_assert(current_audio.pending_events_tail->next == NULL);
+        SDL_assert(current_audio.pending_events_tail);
+        SDL_assert(!current_audio.pending_events_tail->next);
         current_audio.pending_events_tail->next = pending.next;
         current_audio.pending_events_tail = pending_tail;
         SDL_UnlockRWLock(current_audio.device_hash_lock);
@@ -2173,7 +2173,7 @@ int SDL_AudioDeviceFormatChangedAlreadyLocked(SDL_AudioDevice *device, const SDL
             pending_tail = p;
         }
 
-        for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev != NULL; logdev = logdev->next) {
+        for (SDL_LogicalAudioDevice *logdev = device->logical_devices; logdev; logdev = logdev->next) {
             p = (SDL_PendingAudioDeviceEvent *)SDL_malloc(sizeof(SDL_PendingAudioDeviceEvent));
             if (p) { // if this failed, no event for you, but you have deeper problems anyhow.
                 p->type = SDL_EVENT_AUDIO_DEVICE_FORMAT_CHANGED;
@@ -2186,8 +2186,8 @@ int SDL_AudioDeviceFormatChangedAlreadyLocked(SDL_AudioDevice *device, const SDL
 
         if (pending.next) {
             SDL_LockRWLockForWriting(current_audio.device_hash_lock);
-            SDL_assert(current_audio.pending_events_tail != NULL);
-            SDL_assert(current_audio.pending_events_tail->next == NULL);
+            SDL_assert(current_audio.pending_events_tail);
+            SDL_assert(!current_audio.pending_events_tail->next);
             current_audio.pending_events_tail->next = pending.next;
             current_audio.pending_events_tail = pending_tail;
             SDL_UnlockRWLock(current_audio.device_hash_lock);
@@ -2225,7 +2225,7 @@ void SDL_UpdateAudio(void)
     SDL_UnlockRWLock(current_audio.device_hash_lock);
 
     SDL_PendingAudioDeviceEvent *pending_next = NULL;
-    for (SDL_PendingAudioDeviceEvent *i = pending_events; i != NULL; i = pending_next) {
+    for (SDL_PendingAudioDeviceEvent *i = pending_events; i; i = pending_next) {
         pending_next = i->next;
         if (SDL_EventEnabled(i->type)) {
             SDL_Event event;

src/audio/SDL_audiocvt.c

@@ -221,8 +221,8 @@ static SDL_bool SDL_IsSupportedChannelCount(const int channels)
 void ConvertAudio(int num_frames, const void *src, SDL_AudioFormat src_format, int src_channels,
                   void *dst, SDL_AudioFormat dst_format, int dst_channels, void* scratch)
 {
-    SDL_assert(src != NULL);
-    SDL_assert(dst != NULL);
+    SDL_assert(src);
+    SDL_assert(dst);
     SDL_assert(SDL_IsSupportedAudioFormat(src_format));
     SDL_assert(SDL_IsSupportedAudioFormat(dst_format));
     SDL_assert(SDL_IsSupportedChannelCount(src_channels));
@@ -278,7 +278,7 @@ void ConvertAudio(int num_frames, const void *src, SDL_AudioFormat src_format, i
         }
     }
 
-    if (scratch == NULL) {
+    if (!scratch) {
         scratch = dst;
     }
 
@@ -313,7 +313,7 @@ void ConvertAudio(int num_frames, const void *src, SDL_AudioFormat src_format, i
         SDL_assert(dst_channels <= SDL_arraysize(channel_converters[0]));
 
         channel_converter = channel_converters[src_channels - 1][dst_channels - 1];
-        SDL_assert(channel_converter != NULL);
+        SDL_assert(channel_converter);
 
         // swap in some SIMD versions for a few of these.
         if (channel_converter == SDL_ConvertStereoToMono) {
@@ -408,7 +408,7 @@ SDL_AudioStream *SDL_CreateAudioStream(const SDL_AudioSpec *src_spec, const SDL_
     SDL_SetupAudioResampler();
 
     SDL_AudioStream *retval = (SDL_AudioStream *)SDL_calloc(1, sizeof(SDL_AudioStream));
-    if (retval == NULL) {
+    if (!retval) {
         SDL_OutOfMemory();
         return NULL;
     }
@@ -416,13 +416,13 @@ SDL_AudioStream *SDL_CreateAudioStream(const SDL_AudioSpec *src_spec, const SDL_
     retval->freq_ratio = 1.0f;
     retval->queue = SDL_CreateAudioQueue(4096);
 
-    if (retval->queue == NULL) {
+    if (!retval->queue) {
         SDL_free(retval);
         return NULL;
     }
 
     retval->lock = SDL_CreateMutex();
-    if (retval->lock == NULL) {
+    if (!retval->lock) {
         SDL_free(retval->queue);
         SDL_free(retval);
         return NULL;
@@ -632,9 +632,9 @@ int SDL_PutAudioStreamData(SDL_AudioStream *stream, const void *buf, int len)
     SDL_Log("AUDIOSTREAM: wants to put %d bytes", len);
 #endif
 
-    if (stream == NULL) {
+    if (!stream) {
         return SDL_InvalidParamError("stream");
-    } else if (buf == NULL) {
+    } else if (!buf) {
         return SDL_InvalidParamError("buf");
     } else if (len < 0) {
         return SDL_InvalidParamError("len");
@@ -669,7 +669,7 @@ int SDL_PutAudioStreamData(SDL_AudioStream *stream, const void *buf, int len)
         size_t chunk_size = SDL_GetAudioQueueChunkSize(stream->queue);
         track = SDL_CreateChunkedAudioTrack(&src_spec, buf, len, chunk_size);
 
-        if (track == NULL) {
+        if (!track) {
             return -1;
         }
 
@@ -680,7 +680,7 @@ int SDL_PutAudioStreamData(SDL_AudioStream *stream, const void *buf, int len)
 
     int retval = 0;
 
-    if (track != NULL) {
+    if (track) {
         SDL_AddTrackToAudioQueue(stream->queue, track);
     } else {
         retval = SDL_WriteToAudioQueue(stream->queue, &stream->src_spec, buf, len);
@@ -701,7 +701,7 @@ int SDL_PutAudioStreamData(SDL_AudioStream *stream, const void *buf, int len)
 
 int SDL_FlushAudioStream(SDL_AudioStream *stream)
 {
-    if (stream == NULL) {
+    if (!stream) {
         return SDL_InvalidParamError("stream");
     }
 
@@ -721,7 +721,7 @@ static Uint8 *EnsureAudioStreamWorkBufferSize(SDL_AudioStream *stream, size_t ne
     }
 
     Uint8 *ptr = (Uint8 *) SDL_aligned_alloc(SDL_SIMDGetAlignment(), newlen);
-    if (ptr == NULL) {
+    if (!ptr) {
         SDL_OutOfMemory();
         return NULL;  // previous work buffer is still valid!
     }
@@ -741,7 +741,7 @@ static void UpdateAudioStreamHistoryBuffer(SDL_AudioStream* stream,
     Uint8 *history_buffer = stream->history_buffer;
     int history_bytes = history_buffer_frames * SDL_AUDIO_FRAMESIZE(stream->input_spec);
 
-    if (left_padding != NULL) {
+    if (left_padding) {
         // Fill in the left padding using the history buffer
         SDL_assert(padding_bytes <= history_bytes);
         SDL_memcpy(left_padding, history_buffer + history_bytes - padding_bytes, padding_bytes);
@@ -835,7 +835,7 @@ static Sint64 GetAudioStreamHead(SDL_AudioStream* stream, SDL_AudioSpec* out_spe
 {
     void* iter = SDL_BeginAudioQueueIter(stream->queue);
 
-    if (iter == NULL) {
+    if (!iter) {
         SDL_zerop(out_spec);
         *out_flushed = SDL_FALSE;
         return 0;
@@ -1025,9 +1025,9 @@ int SDL_GetAudioStreamData(SDL_AudioStream *stream, void *voidbuf, int len)
     SDL_Log("AUDIOSTREAM: want to get %d converted bytes", len);
 #endif
 
-    if (stream == NULL) {
+    if (!stream) {
         return SDL_InvalidParamError("stream");
-    } else if (buf == NULL) {
+    } else if (!buf) {
         return SDL_InvalidParamError("buf");
     } else if (len < 0) {
         return SDL_InvalidParamError("len");
@@ -1160,7 +1160,7 @@ int SDL_GetAudioStreamQueued(SDL_AudioStream *stream)
 
 int SDL_ClearAudioStream(SDL_AudioStream *stream)
 {
-    if (stream == NULL) {
+    if (!stream) {
         return SDL_InvalidParamError("stream");
     }
 
@@ -1177,7 +1177,7 @@ int SDL_ClearAudioStream(SDL_AudioStream *stream)
 
 void SDL_DestroyAudioStream(SDL_AudioStream *stream)
 {
-    if (stream == NULL) {
+    if (!stream) {
         return;
     }
 
@@ -1214,13 +1214,13 @@ int SDL_ConvertAudioSamples(const SDL_AudioSpec *src_spec, const Uint8 *src_data
         *dst_len = 0;
     }
 
-    if (src_data == NULL) {
+    if (!src_data) {
         return SDL_InvalidParamError("src_data");
     } else if (src_len < 0) {
         return SDL_InvalidParamError("src_len");
-    } else if (dst_data == NULL) {
+    } else if (!dst_data) {
         return SDL_InvalidParamError("dst_data");
-    } else if (dst_len == NULL) {
+    } else if (!dst_len) {
         return SDL_InvalidParamError("dst_len");
     }
 
@@ -1229,7 +1229,7 @@ int SDL_ConvertAudioSamples(const SDL_AudioSpec *src_spec, const Uint8 *src_data
     int dstlen = 0;
 
     SDL_AudioStream *stream = SDL_CreateAudioStream(src_spec, dst_spec);
-    if (stream != NULL) {
+    if (stream) {
         if ((SDL_PutAudioStreamData(stream, src_data, src_len) == 0) && (SDL_FlushAudioStream(stream) == 0)) {
             dstlen = SDL_GetAudioStreamAvailable(stream);
             if (dstlen >= 0) {

src/audio/SDL_audiodev.c

@@ -80,16 +80,16 @@ static void SDL_EnumUnixAudioDevices_Internal(const SDL_bool iscapture, const SD
     const char *audiodev;
     char audiopath[1024];
 
-    if (test == NULL) {
+    if (!test) {
         test = test_stub;
     }
 
     // Figure out what our audio device is
     audiodev = SDL_getenv("SDL_PATH_DSP");
-    if (audiodev == NULL) {
+    if (!audiodev) {
         audiodev = SDL_getenv("AUDIODEV");
     }
-    if (audiodev == NULL) {
+    if (!audiodev) {
         if (classic) {
             audiodev = SDL_PATH_DEV_AUDIO;
         } else {

src/audio/SDL_audioqueue.c

@@ -92,7 +92,7 @@ static SDL_AudioChunk *CreateAudioChunk(size_t chunk_size)
 {
     SDL_AudioChunk *chunk = (SDL_AudioChunk *)SDL_malloc(sizeof(*chunk) + chunk_size);
 
-    if (chunk == NULL) {
+    if (!chunk) {
         return NULL;
     }
 
@@ -146,14 +146,14 @@ static int WriteToChunkedAudioTrack(void *ctx, const Uint8 *data, size_t len)
     SDL_AudioChunk *chunk = track->tail;
 
     // Handle the first chunk
-    if (chunk == NULL) {
+    if (!chunk) {
         chunk = CreateAudioTrackChunk(track);
 
-        if (chunk == NULL) {
+        if (!chunk) {
             return SDL_OutOfMemory();
         }
 
-        SDL_assert((track->head == NULL) && (track->tail == NULL) && (track->queued_bytes == 0));
+        SDL_assert((!track->head) && (!track->tail) && (track->queued_bytes == 0));
         track->head = chunk;
         track->tail = chunk;
     }
@@ -180,7 +180,7 @@ static int WriteToChunkedAudioTrack(void *ctx, const Uint8 *data, size_t len)
     }
 
     // Roll back the changes if we couldn't write all the data
-    if (chunk == NULL) {
+    if (!chunk) {
         chunk = track->tail;
 
         SDL_AudioChunk *next = chunk->next;
@@ -255,7 +255,7 @@ static SDL_AudioTrack *CreateChunkedAudioTrack(const SDL_AudioSpec *spec, size_t
 {
     SDL_ChunkedAudioTrack *track = (SDL_ChunkedAudioTrack *)SDL_calloc(1, sizeof(*track));
 
-    if (track == NULL) {
+    if (!track) {
         SDL_OutOfMemory();
         return NULL;
     }
@@ -275,7 +275,7 @@ SDL_AudioQueue *SDL_CreateAudioQueue(size_t chunk_size)
 {
     SDL_AudioQueue *queue = (SDL_AudioQueue *)SDL_calloc(1, sizeof(*queue));
 
-    if (queue == NULL) {
+    if (!queue) {
         SDL_OutOfMemory();
         return NULL;
     }
@@ -338,7 +338,7 @@ void SDL_PopAudioQueueHead(SDL_AudioQueue *queue)
 
     queue->head = track;
 
-    if (track == NULL) {
+    if (!track) {
         queue->tail = NULL;
     }
 }
@@ -352,7 +352,7 @@ SDL_AudioTrack *SDL_CreateChunkedAudioTrack(const SDL_AudioSpec *spec, const Uin
 {
     SDL_AudioTrack *track = CreateChunkedAudioTrack(spec, chunk_size);
 
-    if (track == NULL) {
+    if (!track) {
         return NULL;
     }
 
@@ -390,14 +390,14 @@ int SDL_WriteToAudioQueue(SDL_AudioQueue *queue, const SDL_AudioSpec *spec, cons
 
     SDL_AudioTrack *track = queue->tail;
 
-    if ((track != NULL) && !AUDIO_SPECS_EQUAL(track->spec, *spec)) {
+    if ((track) && !AUDIO_SPECS_EQUAL(track->spec, *spec)) {
         SDL_FlushAudioTrack(track);
     }
 
-    if ((track == NULL) || (track->write == NULL)) {
+    if ((!track) || (!track->write)) {
         SDL_AudioTrack *new_track = CreateChunkedAudioTrack(spec, queue->chunk_size);
 
-        if (new_track == NULL) {
+        if (!new_track) {
             return SDL_OutOfMemory();
         }
 
@@ -423,7 +423,7 @@ void *SDL_BeginAudioQueueIter(SDL_AudioQueue *queue)
 size_t SDL_NextAudioQueueIter(SDL_AudioQueue *queue, void **inout_iter, SDL_AudioSpec *out_spec, SDL_bool *out_flushed)
 {
     SDL_AudioTrack *iter = *inout_iter;
-    SDL_assert(iter != NULL);
+    SDL_assert(iter);
 
     SDL_copyp(out_spec, &iter->spec);
 
@@ -462,7 +462,7 @@ int SDL_ReadFromAudioQueue(SDL_AudioQueue *queue, Uint8 *data, size_t len)
     SDL_AudioTrack *track = queue->head;
 
     for (;;) {
-        if (track == NULL) {
+        if (!track) {
             return SDL_SetError("Reading past end of queue");
         }
 
@@ -478,7 +478,7 @@ int SDL_ReadFromAudioQueue(SDL_AudioQueue *queue, Uint8 *data, size_t len)
 
         SDL_AudioTrack *next = track->next;
 
-        if (next == NULL) {
+        if (!next) {
             return SDL_SetError("Reading past end of incomplete track");
         }
 
@@ -495,7 +495,7 @@ int SDL_PeekIntoAudioQueue(SDL_AudioQueue *queue, Uint8 *data, size_t len)
     SDL_AudioTrack *track = queue->head;
 
     for (;;) {
-        if (track == NULL) {
+        if (!track) {
             return SDL_SetError("Peeking past end of queue");
         }
 

src/audio/SDL_wave.c

@@ -262,7 +262,7 @@ static void WaveDebugDumpFormat(WaveFile *file, Uint32 rifflen, Uint32 fmtlen, U
     int res;
 
     dumpstr = SDL_malloc(bufsize);
-    if (dumpstr == NULL) {
+    if (!dumpstr) {
         return;
     }
     dumpstr[0] = 0;
@@ -439,7 +439,7 @@ static int MS_ADPCM_Init(WaveFile *file, size_t datalength)
 
     coeffdata = (MS_ADPCM_CoeffData *)SDL_malloc(sizeof(MS_ADPCM_CoeffData) + coeffcount * 4);
     file->decoderdata = coeffdata; /* Freed in cleanup. */
-    if (coeffdata == NULL) {
+    if (!coeffdata) {
         return SDL_OutOfMemory();
     }
     coeffdata->coeff = &coeffdata->aligndummy;
@@ -682,7 +682,7 @@ static int MS_ADPCM_Decode(WaveFile *file, Uint8 **audio_buf, Uint32 *audio_len)
     state.output.pos = 0;
     state.output.size = outputsize / sizeof(Sint16);
     state.output.data = (Sint16 *)SDL_calloc(1, outputsize);
-    if (state.output.data == NULL) {
+    if (!state.output.data) {
         return SDL_OutOfMemory();
     }
 
@@ -1073,12 +1073,12 @@ static int IMA_ADPCM_Decode(WaveFile *file, Uint8 **audio_buf, Uint32 *audio_len
     state.output.pos = 0;
     state.output.size = outputsize / sizeof(Sint16);
     state.output.data = (Sint16 *)SDL_malloc(outputsize);
-    if (state.output.data == NULL) {
+    if (!state.output.data) {
         return SDL_OutOfMemory();
     }
 
     cstate = (Sint8 *)SDL_calloc(state.channels, sizeof(Sint8));
-    if (cstate == NULL) {
+    if (!cstate) {
         SDL_free(state.output.data);
         return SDL_OutOfMemory();
     }
@@ -1233,7 +1233,7 @@ static int LAW_Decode(WaveFile *file, Uint8 **audio_buf, Uint32 *audio_len)
 
     /* 1 to avoid allocating zero bytes, to keep static analysis happy. */
     src = (Uint8 *)SDL_realloc(chunk->data, expanded_len ? expanded_len : 1);
-    if (src == NULL) {
+    if (!src) {
         return SDL_OutOfMemory();
     }
     chunk->data = NULL;
@@ -1364,7 +1364,7 @@ static int PCM_ConvertSint24ToSint32(WaveFile *file, Uint8 **audio_buf, Uint32 *
 
     /* 1 to avoid allocating zero bytes, to keep static analysis happy. */
     ptr = (Uint8 *)SDL_realloc(chunk->data, expanded_len ? expanded_len : 1);
-    if (ptr == NULL) {
+    if (!ptr) {
         return SDL_OutOfMemory();
     }
 
@@ -1440,7 +1440,7 @@ static WaveRiffSizeHint WaveGetRiffSizeHint(void)
 {
     const char *hint = SDL_GetHint(SDL_HINT_WAVE_RIFF_CHUNK_SIZE);
 
-    if (hint != NULL) {
+    if (hint) {
         if (SDL_strcmp(hint, "force") == 0) {
             return RiffSizeForce;
         } else if (SDL_strcmp(hint, "ignore") == 0) {
@@ -1459,7 +1459,7 @@ static WaveTruncationHint WaveGetTruncationHint(void)
 {
     const char *hint = SDL_GetHint(SDL_HINT_WAVE_TRUNCATION);
 
-    if (hint != NULL) {
+    if (hint) {
         if (SDL_strcmp(hint, "verystrict") == 0) {
             return TruncVeryStrict;
         } else if (SDL_strcmp(hint, "strict") == 0) {
@@ -1478,7 +1478,7 @@ static WaveFactChunkHint WaveGetFactChunkHint(void)
 {
     const char *hint = SDL_GetHint(SDL_HINT_WAVE_FACT_CHUNK);
 
-    if (hint != NULL) {
+    if (hint) {
         if (SDL_strcmp(hint, "truncate") == 0) {
             return FactTruncate;
         } else if (SDL_strcmp(hint, "strict") == 0) {
@@ -1495,7 +1495,7 @@ static WaveFactChunkHint WaveGetFactChunkHint(void)
 
 static void WaveFreeChunkData(WaveChunk *chunk)
 {
-    if (chunk->data != NULL) {
+    if (chunk->data) {
         SDL_free(chunk->data);
         chunk->data = NULL;
     }
@@ -1544,7 +1544,7 @@ static int WaveReadPartialChunkData(SDL_RWops *src, WaveChunk *chunk, size_t len
 
     if (length > 0) {
         chunk->data = (Uint8 *)SDL_malloc(length);
-        if (chunk->data == NULL) {
+        if (!chunk->data) {
             return SDL_OutOfMemory();
         }
 
@@ -1610,7 +1610,7 @@ static int WaveReadFormat(WaveFile *file)
         return SDL_SetError("Data of WAVE fmt chunk too big");
     }
     fmtsrc = SDL_RWFromConstMem(chunk->data, (int)chunk->size);
-    if (fmtsrc == NULL) {
+    if (!fmtsrc) {
         return SDL_OutOfMemory();
     }
 
@@ -1788,7 +1788,7 @@ static int WaveLoad(SDL_RWops *src, WaveFile *file, SDL_AudioSpec *spec, Uint8 *
     SDL_zero(datachunk);
 
     envchunkcountlimit = SDL_getenv("SDL_WAVE_CHUNK_LIMIT");
-    if (envchunkcountlimit != NULL) {
+    if (envchunkcountlimit) {
         unsigned int count;
         if (SDL_sscanf(envchunkcountlimit, "%u", &count) == 1) {
             chunkcountlimit = count <= SDL_MAX_UINT32 ? count : SDL_MAX_UINT32;
@@ -2081,15 +2081,15 @@ int SDL_LoadWAV_RW(SDL_RWops *src, SDL_bool freesrc, SDL_AudioSpec *spec, Uint8
     WaveFile file;
 
     /* Make sure we are passed a valid data source */
-    if (src == NULL) {
+    if (!src) {
         goto done;  /* Error may come from RWops. */
-    } else if (spec == NULL) {
+    } else if (!spec) {
         SDL_InvalidParamError("spec");
         goto done;
-    } else if (audio_buf == NULL) {
+    } else if (!audio_buf) {
         SDL_InvalidParamError("audio_buf");
         goto done;
-    } else if (audio_len == NULL) {
+    } else if (!audio_len) {
         SDL_InvalidParamError("audio_len");
         goto done;
     }

src/audio/aaudio/SDL_aaudio.c

@@ -282,7 +282,7 @@ static int BuildAAudioStream(SDL_AudioDevice *device)
     if (res != AAUDIO_OK) {
         LOGI("SDL Failed AAudio_createStreamBuilder %d", res);
         return SDL_SetError("SDL Failed AAudio_createStreamBuilder %d", res);
-    } else if (builder == NULL) {
+    } else if (!builder) {
         LOGI("SDL Failed AAudio_createStreamBuilder - builder NULL");
         return SDL_SetError("SDL Failed AAudio_createStreamBuilder - builder NULL");
     }
@@ -354,7 +354,7 @@ static int BuildAAudioStream(SDL_AudioDevice *device)
     hidden->num_buffers = 2;
     hidden->mixbuf_bytes = (hidden->num_buffers * device->buffer_size);
     hidden->mixbuf = (Uint8 *)SDL_aligned_alloc(SDL_SIMDGetAlignment(), hidden->mixbuf_bytes);
-    if (hidden->mixbuf == NULL) {
+    if (!hidden->mixbuf) {
         return SDL_OutOfMemory();
     }
     hidden->processed_bytes = 0;
@@ -384,7 +384,7 @@ static int BuildAAudioStream(SDL_AudioDevice *device)
 static int AAUDIO_OpenDevice(SDL_AudioDevice *device)
 {
 #if ALLOW_MULTIPLE_ANDROID_AUDIO_DEVICES
-    SDL_assert(device->handle != NULL);  // AAUDIO_UNSPECIFIED is zero, so legit devices should all be non-zero.
+    SDL_assert(device->handle);  // AAUDIO_UNSPECIFIED is zero, so legit devices should all be non-zero.
 #endif
 
     LOGI(__func__);
@@ -397,7 +397,7 @@ static int AAUDIO_OpenDevice(SDL_AudioDevice *device)
     }
 
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -407,7 +407,7 @@ static int AAUDIO_OpenDevice(SDL_AudioDevice *device)
 static SDL_bool PauseOneDevice(SDL_AudioDevice *device, void *userdata)
 {
     struct SDL_PrivateAudioData *hidden = (struct SDL_PrivateAudioData *)device->hidden;
-    if (hidden != NULL) {
+    if (hidden) {
         if (hidden->stream) {
             aaudio_result_t res;
 
@@ -433,7 +433,7 @@ static SDL_bool PauseOneDevice(SDL_AudioDevice *device, void *userdata)
 // Pause (block) all non already paused audio devices by taking their mixer lock
 void AAUDIO_PauseDevices(void)
 {
-    if (ctx.handle != NULL) {  // AAUDIO driver is used?
+    if (ctx.handle) {  // AAUDIO driver is used?
         (void) SDL_FindPhysicalAudioDeviceByCallback(PauseOneDevice, NULL);
     }
 }
@@ -442,7 +442,7 @@ void AAUDIO_PauseDevices(void)
 static SDL_bool ResumeOneDevice(SDL_AudioDevice *device, void *userdata)
 {
     struct SDL_PrivateAudioData *hidden = device->hidden;
-    if (hidden != NULL) {
+    if (hidden) {
         if (hidden->resume) {
             hidden->resume = SDL_FALSE;
             SDL_UnlockMutex(device->lock);
@@ -461,7 +461,7 @@ static SDL_bool ResumeOneDevice(SDL_AudioDevice *device, void *userdata)
 
 void AAUDIO_ResumeDevices(void)
 {
-    if (ctx.handle != NULL) {  // AAUDIO driver is used?
+    if (ctx.handle) {  // AAUDIO driver is used?
         (void) SDL_FindPhysicalAudioDeviceByCallback(ResumeOneDevice, NULL);
     }
 }
@@ -495,7 +495,7 @@ static SDL_bool AAUDIO_Init(SDL_AudioDriverImpl *impl)
     SDL_zero(ctx);
 
     ctx.handle = SDL_LoadObject(LIB_AAUDIO_SO);
-    if (ctx.handle == NULL) {
+    if (!ctx.handle) {
         LOGI("SDL couldn't find " LIB_AAUDIO_SO);
         return SDL_FALSE;
     }

src/audio/alsa/SDL_alsa_audio.c

@@ -96,7 +96,7 @@ static void *alsa_handle = NULL;
 static int load_alsa_sym(const char *fn, void **addr)
 {
     *addr = SDL_LoadFunction(alsa_handle, fn);
-    if (*addr == NULL) {
+    if (!*addr) {
         // Don't call SDL_SetError(): SDL_LoadFunction already did.
         return 0;
     }
@@ -165,7 +165,7 @@ static int load_alsa_syms(void)
 
 static void UnloadALSALibrary(void)
 {
-    if (alsa_handle != NULL) {
+    if (alsa_handle) {
         SDL_UnloadObject(alsa_handle);
         alsa_handle = NULL;
     }
@@ -174,9 +174,9 @@ static void UnloadALSALibrary(void)
 static int LoadALSALibrary(void)
 {
     int retval = 0;
-    if (alsa_handle == NULL) {
+    if (!alsa_handle) {
         alsa_handle = SDL_LoadObject(alsa_library);
-        if (alsa_handle == NULL) {
+        if (!alsa_handle) {
             retval = -1;
             // Don't call SDL_SetError(): SDL_LoadObject already did.
         } else {
@@ -224,12 +224,12 @@ static const ALSA_Device default_capture_handle = {
 
 static const char *get_audio_device(void *handle, const int channels)
 {
-    SDL_assert(handle != NULL);  // SDL2 used NULL to mean "default" but that's not true in SDL3.
+    SDL_assert(handle);  // SDL2 used NULL to mean "default" but that's not true in SDL3.
 
     ALSA_Device *dev = (ALSA_Device *)handle;
     if (SDL_strcmp(dev->name, "default") == 0) {
         const char *device = SDL_getenv("AUDIODEV"); // Is there a standard variable name?
-        if (device != NULL) {
+        if (device) {
             return device;
         } else if (channels == 6) {
             return "plug:surround51";
@@ -536,7 +536,7 @@ static int ALSA_OpenDevice(SDL_AudioDevice *device)
 
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -682,7 +682,7 @@ static int ALSA_OpenDevice(SDL_AudioDevice *device)
     // Allocate mixing buffer
     if (!iscapture) {
         device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-        if (device->hidden->mixbuf == NULL) {
+        if (!device->hidden->mixbuf) {
             return SDL_OutOfMemory();
         }
         SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);
@@ -705,7 +705,7 @@ static void add_device(const SDL_bool iscapture, const char *name, void *hint, A
     char *desc;
     char *ptr;
 
-    if (dev == NULL) {
+    if (!dev) {
         return;
     }
 
@@ -715,7 +715,7 @@ static void add_device(const SDL_bool iscapture, const char *name, void *hint, A
     //  Make sure not to free the storage associated with desc in this case
     if (hint) {
         desc = ALSA_snd_device_name_get_hint(hint, "DESC");
-        if (desc == NULL) {
+        if (!desc) {
             SDL_free(dev);
             return;
         }
@@ -723,13 +723,13 @@ static void add_device(const SDL_bool iscapture, const char *name, void *hint, A
         desc = (char *)name;
     }
 
-    SDL_assert(name != NULL);
+    SDL_assert(name);
 
     // some strings have newlines, like "HDA NVidia, HDMI 0\nHDMI Audio Output".
     //  just chop the extra lines off, this seems to get a reasonable device
     //  name without extra details.
     ptr = SDL_strchr(desc, '\n');
-    if (ptr != NULL) {
+    if (ptr) {
         *ptr = '\0';
     }
 
@@ -784,7 +784,7 @@ static void ALSA_HotplugIteration(SDL_bool *has_default_output, SDL_bool *has_de
         //  if we can find a preferred prefix for the system.
         for (int i = 0; hints[i]; i++) {
             char *name = ALSA_snd_device_name_get_hint(hints[i], "NAME");
-            if (name == NULL) {
+            if (!name) {
                 continue;
             }
 
@@ -813,16 +813,16 @@ static void ALSA_HotplugIteration(SDL_bool *has_default_output, SDL_bool *has_de
         if (match || (has_default >= 0)) {  // did we find a device name prefix we like at all...?
             for (int i = 0; hints[i]; i++) {
                 char *name = ALSA_snd_device_name_get_hint(hints[i], "NAME");
-                if (name == NULL) {
+                if (!name) {
                     continue;
                 }
 
                 // only want physical hardware interfaces
                 const SDL_bool is_default = (has_default == i);
-                if (is_default || (match != NULL && SDL_strncmp(name, match, match_len) == 0)) {
+                if (is_default || (match && SDL_strncmp(name, match, match_len) == 0)) {
                     char *ioid = ALSA_snd_device_name_get_hint(hints[i], "IOID");
-                    const SDL_bool isoutput = (ioid == NULL) || (SDL_strcmp(ioid, "Output") == 0);
-                    const SDL_bool isinput = (ioid == NULL) || (SDL_strcmp(ioid, "Input") == 0);
+                    const SDL_bool isoutput = (!ioid) || (SDL_strcmp(ioid, "Output") == 0);
+                    const SDL_bool isinput = (!ioid) || (SDL_strcmp(ioid, "Input") == 0);
                     SDL_bool have_output = SDL_FALSE;
                     SDL_bool have_input = SDL_FALSE;
 
@@ -942,7 +942,7 @@ static void ALSA_DeinitializeStart(void)
     ALSA_Device *next;
 
 #if SDL_ALSA_HOTPLUG_THREAD
-    if (ALSA_hotplug_thread != NULL) {
+    if (ALSA_hotplug_thread) {
         SDL_AtomicSet(&ALSA_hotplug_shutdown, 1);
         SDL_WaitThread(ALSA_hotplug_thread, NULL);
         ALSA_hotplug_thread = NULL;

src/audio/android/SDL_androidaudio.c

@@ -42,7 +42,7 @@ static SDL_AudioDevice *captureDevice = NULL;
 static int ANDROIDAUDIO_OpenDevice(SDL_AudioDevice *device)
 {
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -131,13 +131,13 @@ void ANDROIDAUDIO_PauseDevices(void)
 {
     // TODO: Handle multiple devices?
     struct SDL_PrivateAudioData *hidden;
-    if (audioDevice != NULL && audioDevice->hidden != NULL) {
+    if (audioDevice && audioDevice->hidden) {
         hidden = (struct SDL_PrivateAudioData *)audioDevice->hidden;
         SDL_LockMutex(audioDevice->lock);
         hidden->resume = SDL_TRUE;
     }
 
-    if (captureDevice != NULL && captureDevice->hidden != NULL) {
+    if (captureDevice && captureDevice->hidden) {
         hidden = (struct SDL_PrivateAudioData *)captureDevice->hidden;
         SDL_LockMutex(captureDevice->lock);
         hidden->resume = SDL_TRUE;
@@ -149,7 +149,7 @@ void ANDROIDAUDIO_ResumeDevices(void)
 {
     // TODO: Handle multiple devices?
     struct SDL_PrivateAudioData *hidden;
-    if (audioDevice != NULL && audioDevice->hidden != NULL) {
+    if (audioDevice && audioDevice->hidden) {
         hidden = (struct SDL_PrivateAudioData *)audioDevice->hidden;
         if (hidden->resume) {
             hidden->resume = SDL_FALSE;
@@ -157,7 +157,7 @@ void ANDROIDAUDIO_ResumeDevices(void)
         }
     }
 
-    if (captureDevice != NULL && captureDevice->hidden != NULL) {
+    if (captureDevice && captureDevice->hidden) {
         hidden = (struct SDL_PrivateAudioData *)captureDevice->hidden;
         if (hidden->resume) {
             hidden->resume = SDL_FALSE;

src/audio/directsound/SDL_directsound.c

@@ -62,7 +62,7 @@ static void DSOUND_Unload(void)
     pDirectSoundCaptureEnumerateW = NULL;
     pGetDeviceID = NULL;
 
-    if (DSoundDLL != NULL) {
+    if (DSoundDLL) {
         SDL_UnloadObject(DSoundDLL);
         DSoundDLL = NULL;
     }
@@ -75,7 +75,7 @@ static int DSOUND_Load(void)
     DSOUND_Unload();
 
     DSoundDLL = SDL_LoadObject("DSOUND.DLL");
-    if (DSoundDLL == NULL) {
+    if (!DSoundDLL) {
         SDL_SetError("DirectSound: failed to load DSOUND.DLL");
     } else {
 // Now make sure we have DirectX 8 or better...
@@ -176,7 +176,7 @@ static BOOL CALLBACK FindAllDevs(LPGUID guid, LPCWSTR desc, LPCWSTR module, LPVO
     FindAllDevsData *data = (FindAllDevsData *) userdata;
     if (guid != NULL) { // skip default device
         char *str = WIN_LookupAudioDeviceName(desc, guid);
-        if (str != NULL) {
+        if (str) {
             LPGUID cpyguid = (LPGUID)SDL_malloc(sizeof(GUID));
             if (cpyguid) {
                 SDL_copyp(cpyguid, guid);
@@ -358,7 +358,7 @@ static int DSOUND_CaptureFromDevice(SDL_AudioDevice *device, void *buffer, int b
     }
 
     SDL_assert(ptr1len == (DWORD)buflen);
-    SDL_assert(ptr2 == NULL);
+    SDL_assert(!ptr2);
     SDL_assert(ptr2len == 0);
 
     SDL_memcpy(buffer, ptr1, ptr1len);
@@ -384,18 +384,18 @@ static void DSOUND_FlushCapture(SDL_AudioDevice *device)
 static void DSOUND_CloseDevice(SDL_AudioDevice *device)
 {
     if (device->hidden) {
-        if (device->hidden->mixbuf != NULL) {
+        if (device->hidden->mixbuf) {
             IDirectSoundBuffer_Stop(device->hidden->mixbuf);
             IDirectSoundBuffer_Release(device->hidden->mixbuf);
         }
-        if (device->hidden->sound != NULL) {
+        if (device->hidden->sound) {
             IDirectSound_Release(device->hidden->sound);
         }
-        if (device->hidden->capturebuf != NULL) {
+        if (device->hidden->capturebuf) {
             IDirectSoundCaptureBuffer_Stop(device->hidden->capturebuf);
             IDirectSoundCaptureBuffer_Release(device->hidden->capturebuf);
         }
-        if (device->hidden->capture != NULL) {
+        if (device->hidden->capture) {
             IDirectSoundCapture_Release(device->hidden->capture);
         }
         SDL_free(device->hidden);
@@ -491,7 +491,7 @@ static int DSOUND_OpenDevice(SDL_AudioDevice *device)
 {
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 

src/audio/disk/SDL_diskaudio.c

@@ -87,7 +87,7 @@ static void DISKAUDIO_FlushCapture(SDL_AudioDevice *device)
 static void DISKAUDIO_CloseDevice(SDL_AudioDevice *device)
 {
     if (device->hidden) {
-        if (device->hidden->io != NULL) {
+        if (device->hidden->io) {
             SDL_RWclose(device->hidden->io);
         }
         SDL_free(device->hidden->mixbuf);
@@ -99,7 +99,7 @@ static void DISKAUDIO_CloseDevice(SDL_AudioDevice *device)
 static const char *get_filename(const SDL_bool iscapture)
 {
     const char *devname = SDL_getenv(iscapture ? DISKENVR_INFILE : DISKENVR_OUTFILE);
-    if (devname == NULL) {
+    if (!devname) {
         devname = iscapture ? DISKDEFAULT_INFILE : DISKDEFAULT_OUTFILE;
     }
     return devname;
@@ -112,11 +112,11 @@ static int DISKAUDIO_OpenDevice(SDL_AudioDevice *device)
     const char *envr = SDL_getenv(DISKENVR_IODELAY);
 
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
-    if (envr != NULL) {
+    if (envr) {
         device->hidden->io_delay = SDL_atoi(envr);
     } else {
         device->hidden->io_delay = ((device->sample_frames * 1000) / device->spec.freq);
@@ -124,14 +124,14 @@ static int DISKAUDIO_OpenDevice(SDL_AudioDevice *device)
 
     // Open the "audio device"
     device->hidden->io = SDL_RWFromFile(fname, iscapture ? "rb" : "wb");
-    if (device->hidden->io == NULL) {
+    if (!device->hidden->io) {
         return -1;
     }
 
     // Allocate mixing buffer
     if (!iscapture) {
         device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-        if (device->hidden->mixbuf == NULL) {
+        if (!device->hidden->mixbuf) {
             return SDL_OutOfMemory();
         }
         SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);

src/audio/dsp/SDL_dspaudio.c

@@ -70,7 +70,7 @@ static int DSP_OpenDevice(SDL_AudioDevice *device)
 
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -191,7 +191,7 @@ static int DSP_OpenDevice(SDL_AudioDevice *device)
     // Allocate mixing buffer
     if (!device->iscapture) {
         device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-        if (device->hidden->mixbuf == NULL) {
+        if (!device->hidden->mixbuf) {
             return SDL_OutOfMemory();
         }
         SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);

src/audio/emscripten/SDL_emscriptenaudio.c

@@ -177,7 +177,7 @@ static int EMSCRIPTENAUDIO_OpenDevice(SDL_AudioDevice *device)
 
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -188,7 +188,7 @@ static int EMSCRIPTENAUDIO_OpenDevice(SDL_AudioDevice *device)
 
     if (!device->iscapture) {
         device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-        if (device->hidden->mixbuf == NULL) {
+        if (!device->hidden->mixbuf) {
             return SDL_OutOfMemory();
         }
         SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);

src/audio/haiku/SDL_haikuaudio.cc

@@ -39,7 +39,7 @@ extern "C"
 
 static Uint8 *HAIKUAUDIO_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
 {
-    SDL_assert(device->hidden->current_buffer != NULL);
+    SDL_assert(device->hidden->current_buffer);
     SDL_assert(device->hidden->current_buffer_len > 0);
     *buffer_size = device->hidden->current_buffer_len;
     return device->hidden->current_buffer;
@@ -48,7 +48,7 @@ static Uint8 *HAIKUAUDIO_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
 static int HAIKUAUDIO_PlayDevice(SDL_AudioDevice *device, const Uint8 *buffer, int buffer_size)
 {
     // We already wrote our output right into the BSoundPlayer's callback's stream. Just clean up our stuff.
-    SDL_assert(device->hidden->current_buffer != NULL);
+    SDL_assert(device->hidden->current_buffer);
     SDL_assert(device->hidden->current_buffer_len > 0);
     device->hidden->current_buffer = NULL;
     device->hidden->current_buffer_len = 0;
@@ -59,7 +59,7 @@ static int HAIKUAUDIO_PlayDevice(SDL_AudioDevice *device, const Uint8 *buffer, i
 static void FillSound(void *data, void *stream, size_t len, const media_raw_audio_format & format)
 {
     SDL_AudioDevice *device = (SDL_AudioDevice *)data;
-    SDL_assert(device->hidden->current_buffer == NULL);
+    SDL_assert(!device->hidden->current_buffer);
     SDL_assert(device->hidden->current_buffer_len == 0);
     device->hidden->current_buffer = (Uint8 *) stream;
     device->hidden->current_buffer_len = (int) len;

src/audio/jack/SDL_jackaudio.c

@@ -57,7 +57,7 @@ static void *jack_handle = NULL;
 static int load_jack_sym(const char *fn, void **addr)
 {
     *addr = SDL_LoadFunction(jack_handle, fn);
-    if (*addr == NULL) {
+    if (!*addr) {
         // Don't call SDL_SetError(): SDL_LoadFunction already did.
         return 0;
     }
@@ -72,7 +72,7 @@ static int load_jack_sym(const char *fn, void **addr)
 
 static void UnloadJackLibrary(void)
 {
-    if (jack_handle != NULL) {
+    if (jack_handle) {
         SDL_UnloadObject(jack_handle);
         jack_handle = NULL;
     }
@@ -81,9 +81,9 @@ static void UnloadJackLibrary(void)
 static int LoadJackLibrary(void)
 {
     int retval = 0;
-    if (jack_handle == NULL) {
+    if (!jack_handle) {
         jack_handle = SDL_LoadObject(jack_library);
-        if (jack_handle == NULL) {
+        if (!jack_handle) {
             retval = -1;
             // Don't call SDL_SetError(): SDL_LoadObject already did.
         } else {
@@ -296,18 +296,18 @@ static int JACK_OpenDevice(SDL_AudioDevice *device)
 
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
     client = JACK_jack_client_open(GetJackAppName(), JackNoStartServer, &status, NULL);
     device->hidden->client = client;
-    if (client == NULL) {
+    if (!client) {
         return SDL_SetError("Can't open JACK client");
     }
 
     devports = JACK_jack_get_ports(client, NULL, NULL, JackPortIsPhysical | sysportflags);
-    if (devports == NULL || !devports[0]) {
+    if (!devports || !devports[0]) {
         return SDL_SetError("No physical JACK ports available");
     }
 
@@ -349,7 +349,7 @@ static int JACK_OpenDevice(SDL_AudioDevice *device)
 
     // Build SDL's ports, which we will connect to the device ports.
     device->hidden->sdlports = (jack_port_t **)SDL_calloc(channels, sizeof(jack_port_t *));
-    if (device->hidden->sdlports == NULL) {
+    if (!device->hidden->sdlports) {
         SDL_free(audio_ports);
         return SDL_OutOfMemory();
     }
@@ -414,7 +414,7 @@ static SDL_bool JACK_Init(SDL_AudioDriverImpl *impl)
         // Make sure a JACK server is running and available.
         jack_status_t status;
         jack_client_t *client = JACK_jack_client_open("SDL", JackNoStartServer, &status, NULL);
-        if (client == NULL) {
+        if (!client) {
             UnloadJackLibrary();
             return SDL_FALSE;
         }

src/audio/n3ds/SDL_n3dsaudio.c

@@ -83,7 +83,7 @@ static int N3DSAUDIO_OpenDevice(SDL_AudioDevice *device)
     float mix[12];
 
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -134,14 +134,14 @@ static int N3DSAUDIO_OpenDevice(SDL_AudioDevice *device)
     }
 
     device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-    if (device->hidden->mixbuf == NULL) {
+    if (!device->hidden->mixbuf) {
         return SDL_OutOfMemory();
     }
 
     SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);
 
     data_vaddr = (Uint8 *)linearAlloc(device->buffer_size * NUM_BUFFERS);
-    if (data_vaddr == NULL) {
+    if (!data_vaddr) {
         return SDL_OutOfMemory();
     }
 

src/audio/netbsd/SDL_netbsdaudio.c

@@ -215,7 +215,7 @@ static int NETBSDAUDIO_OpenDevice(SDL_AudioDevice *device)
 
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -293,7 +293,7 @@ static int NETBSDAUDIO_OpenDevice(SDL_AudioDevice *device)
         // Allocate mixing buffer
         device->hidden->mixlen = device->buffer_size;
         device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->hidden->mixlen);
-        if (device->hidden->mixbuf == NULL) {
+        if (!device->hidden->mixbuf) {
             return SDL_OutOfMemory();
         }
         SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);

src/audio/openslES/SDL_openslES.c

@@ -327,7 +327,7 @@ static int OPENSLES_CreatePCMRecorder(SDL_AudioDevice *device)
 
     // Create the sound buffers
     audiodata->mixbuff = (Uint8 *)SDL_malloc(NUM_BUFFERS * device->buffer_size);
-    if (audiodata->mixbuff == NULL) {
+    if (!audiodata->mixbuff) {
         LOGE("mixbuffer allocate - out of memory");
         goto failed;
     }
@@ -574,7 +574,7 @@ static int OPENSLES_CreatePCMPlayer(SDL_AudioDevice *device)
 
     // Create the sound buffers
     audiodata->mixbuff = (Uint8 *)SDL_malloc(NUM_BUFFERS * device->buffer_size);
-    if (audiodata->mixbuff == NULL) {
+    if (!audiodata->mixbuff) {
         LOGE("mixbuffer allocate - out of memory");
         goto failed;
     }
@@ -599,7 +599,7 @@ failed:
 static int OPENSLES_OpenDevice(SDL_AudioDevice *device)
 {
     device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 

src/audio/pipewire/SDL_pipewire.c

@@ -126,7 +126,7 @@ static void *pipewire_handle = NULL;
 static int pipewire_dlsym(const char *fn, void **addr)
 {
     *addr = SDL_LoadFunction(pipewire_handle, fn);
-    if (*addr == NULL) {
+    if (!*addr) {
         // Don't call SDL_SetError(): SDL_LoadFunction already did.
         return 0;
     }
@@ -142,7 +142,7 @@ static int pipewire_dlsym(const char *fn, void **addr)
 static int load_pipewire_library(void)
 {
     pipewire_handle = SDL_LoadObject(pipewire_library);
-    return pipewire_handle != NULL ? 0 : -1;
+    return pipewire_handle ? 0 : -1;
 }
 
 static void unload_pipewire_library(void)
@@ -404,7 +404,7 @@ static void *node_object_new(Uint32 id, const char *type, Uint32 version, const
 
     // Create the proxy object
     proxy = pw_registry_bind(hotplug_registry, id, type, version, sizeof(struct node_object));
-    if (proxy == NULL) {
+    if (!proxy) {
         SDL_SetError("Pipewire: Failed to create proxy object (%i)", errno);
         return NULL;
     }
@@ -623,16 +623,16 @@ static int metadata_property(void *object, Uint32 subject, const char *key, cons
 {
     struct node_object *node = object;
 
-    if (subject == PW_ID_CORE && key != NULL && value != NULL) {
+    if (subject == PW_ID_CORE && key && value) {
         if (!SDL_strcmp(key, "default.audio.sink")) {
-            if (pipewire_default_sink_id != NULL) {
+            if (pipewire_default_sink_id) {
                 SDL_free(pipewire_default_sink_id);
             }
             pipewire_default_sink_id = get_name_from_json(value);
             node->persist = SDL_TRUE;
             change_default_device(pipewire_default_sink_id);
         } else if (!SDL_strcmp(key, "default.audio.source")) {
-            if (pipewire_default_source_id != NULL) {
+            if (pipewire_default_source_id) {
                 SDL_free(pipewire_default_source_id);
             }
             pipewire_default_source_id = get_name_from_json(value);
@@ -678,7 +678,7 @@ static void registry_event_global_callback(void *object, uint32_t id, uint32_t p
 
             if (node_desc && node_path) {
                 node = node_object_new(id, type, version, &interface_node_events, &interface_core_events);
-                if (node == NULL) {
+                if (!node) {
                     SDL_SetError("Pipewire: Failed to allocate interface node");
                     return;
                 }
@@ -687,7 +687,7 @@ static void registry_event_global_callback(void *object, uint32_t id, uint32_t p
                 desc_buffer_len = SDL_strlen(node_desc) + 1;
                 path_buffer_len = SDL_strlen(node_path) + 1;
                 node->userdata = io = SDL_calloc(1, sizeof(struct io_node) + desc_buffer_len + path_buffer_len);
-                if (io == NULL) {
+                if (!io) {
                     node_object_destroy(node);
                     SDL_OutOfMemory();
                     return;
@@ -708,7 +708,7 @@ static void registry_event_global_callback(void *object, uint32_t id, uint32_t p
         }
     } else if (!SDL_strcmp(type, PW_TYPE_INTERFACE_Metadata)) {
         node = node_object_new(id, type, version, &metadata_node_events, &metadata_core_events);
-        if (node == NULL) {
+        if (!node) {
             SDL_SetError("Pipewire: Failed to allocate metadata node");
             return;
         }
@@ -736,22 +736,22 @@ static int hotplug_loop_init(void)
     spa_list_init(&hotplug_io_list);
 
     hotplug_loop = PIPEWIRE_pw_thread_loop_new("SDLAudioHotplug", NULL);
-    if (hotplug_loop == NULL) {
+    if (!hotplug_loop) {
         return SDL_SetError("Pipewire: Failed to create hotplug detection loop (%i)", errno);
     }
 
     hotplug_context = PIPEWIRE_pw_context_new(PIPEWIRE_pw_thread_loop_get_loop(hotplug_loop), NULL, 0);
-    if (hotplug_context == NULL) {
+    if (!hotplug_context) {
         return SDL_SetError("Pipewire: Failed to create hotplug detection context (%i)", errno);
     }
 
     hotplug_core = PIPEWIRE_pw_context_connect(hotplug_context, NULL, 0);
-    if (hotplug_core == NULL) {
+    if (!hotplug_core) {
         return SDL_SetError("Pipewire: Failed to connect hotplug detection context (%i)", errno);
     }
 
     hotplug_registry = pw_core_get_registry(hotplug_core, PW_VERSION_REGISTRY, 0);
-    if (hotplug_registry == NULL) {
+    if (!hotplug_registry) {
         return SDL_SetError("Pipewire: Failed to acquire hotplug detection registry (%i)", errno);
     }
 
@@ -783,11 +783,11 @@ static void hotplug_loop_destroy(void)
     hotplug_init_complete = SDL_FALSE;
     hotplug_events_enabled = SDL_FALSE;
 
-    if (pipewire_default_sink_id != NULL) {
+    if (pipewire_default_sink_id) {
         SDL_free(pipewire_default_sink_id);
         pipewire_default_sink_id = NULL;
     }
-    if (pipewire_default_source_id != NULL) {
+    if (pipewire_default_source_id) {
         SDL_free(pipewire_default_source_id);
         pipewire_default_source_id = NULL;
     }
@@ -826,10 +826,10 @@ static void PIPEWIRE_DetectDevices(SDL_AudioDevice **default_output, SDL_AudioDe
 
     spa_list_for_each (io, &hotplug_io_list, link) {
         SDL_AudioDevice *device = SDL_AddAudioDevice(io->is_capture, io->name, &io->spec, PW_ID_TO_HANDLE(io->id));
-        if (pipewire_default_sink_id != NULL && SDL_strcmp(io->path, pipewire_default_sink_id) == 0) {
+        if (pipewire_default_sink_id && SDL_strcmp(io->path, pipewire_default_sink_id) == 0) {
             SDL_assert(!io->is_capture);
             *default_output = device;
-        } else if (pipewire_default_source_id != NULL && SDL_strcmp(io->path, pipewire_default_source_id) == 0) {
+        } else if (pipewire_default_source_id && SDL_strcmp(io->path, pipewire_default_source_id) == 0) {
             SDL_assert(io->is_capture);
             *default_capture = device;
         }
@@ -965,7 +965,7 @@ static void PIPEWIRE_FlushCapture(SDL_AudioDevice *device)
 {
     struct pw_stream *stream = device->hidden->stream;
     struct pw_buffer *pw_buf = PIPEWIRE_pw_stream_dequeue_buffer(stream);
-    if (pw_buf != NULL) {  // just requeue it without any further thought.
+    if (pw_buf) {  // just requeue it without any further thought.
         PIPEWIRE_pw_stream_queue_buffer(stream, pw_buf);
     }
 }
@@ -1062,7 +1062,7 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
     struct SDL_PrivateAudioData *priv;
     struct pw_properties *props;
     const char *app_name, *app_id, *stream_name, *stream_role, *error;
-    Uint32 node_id = device->handle == NULL ? PW_ID_ANY : PW_HANDLE_TO_ID(device->handle);
+    Uint32 node_id = !device->handle ? PW_ID_ANY : PW_HANDLE_TO_ID(device->handle);
     const SDL_bool iscapture = device->iscapture;
     int res;
 
@@ -1071,9 +1071,9 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
 
     // Get the hints for the application name, stream name and role
     app_name = SDL_GetHint(SDL_HINT_AUDIO_DEVICE_APP_NAME);
-    if (app_name == NULL || *app_name == '\0') {
+    if (!app_name || *app_name == '\0') {
         app_name = SDL_GetHint(SDL_HINT_APP_NAME);
-        if (app_name == NULL || *app_name == '\0') {
+        if (!app_name || *app_name == '\0') {
             app_name = "SDL Application";
         }
     }
@@ -1082,7 +1082,7 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
     app_id = SDL_GetHint(SDL_HINT_APP_ID);
 
     stream_name = SDL_GetHint(SDL_HINT_AUDIO_DEVICE_STREAM_NAME);
-    if (stream_name == NULL || *stream_name == '\0') {
+    if (!stream_name || *stream_name == '\0') {
         stream_name = "Audio Stream";
     }
 
@@ -1091,20 +1091,20 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
      * but 'Game' seems more appropriate for the majority of SDL applications.
      */
     stream_role = SDL_GetHint(SDL_HINT_AUDIO_DEVICE_STREAM_ROLE);
-    if (stream_role == NULL || *stream_role == '\0') {
+    if (!stream_role || *stream_role == '\0') {
         stream_role = "Game";
     }
 
     // Initialize the Pipewire stream info from the SDL audio spec
     initialize_spa_info(&device->spec, &spa_info);
     params = spa_format_audio_raw_build(&b, SPA_PARAM_EnumFormat, &spa_info);
-    if (params == NULL) {
+    if (!params) {
         return SDL_SetError("Pipewire: Failed to set audio format parameters");
     }
 
     priv = SDL_calloc(1, sizeof(struct SDL_PrivateAudioData));
     device->hidden = priv;
-    if (priv == NULL) {
+    if (!priv) {
         return SDL_OutOfMemory();
     }
 
@@ -1119,23 +1119,23 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
 
     SDL_GetAudioThreadName(device, thread_name, sizeof(thread_name));
     priv->loop = PIPEWIRE_pw_thread_loop_new(thread_name, NULL);
-    if (priv->loop == NULL) {
+    if (!priv->loop) {
         return SDL_SetError("Pipewire: Failed to create stream loop (%i)", errno);
     }
 
     // Load the realtime module so Pipewire can set the loop thread to the appropriate priority.
     props = PIPEWIRE_pw_properties_new(PW_KEY_CONFIG_NAME, "client-rt.conf", NULL);
-    if (props == NULL) {
+    if (!props) {
         return SDL_SetError("Pipewire: Failed to create stream context properties (%i)", errno);
     }
 
     priv->context = PIPEWIRE_pw_context_new(PIPEWIRE_pw_thread_loop_get_loop(priv->loop), props, 0);
-    if (priv->context == NULL) {
+    if (!priv->context) {
         return SDL_SetError("Pipewire: Failed to create stream context (%i)", errno);
     }
 
     props = PIPEWIRE_pw_properties_new(NULL, NULL);
-    if (props == NULL) {
+    if (!props) {
         return SDL_SetError("Pipewire: Failed to create stream properties (%i)", errno);
     }
 
@@ -1143,7 +1143,7 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
     PIPEWIRE_pw_properties_set(props, PW_KEY_MEDIA_CATEGORY, iscapture ? "Capture" : "Playback");
     PIPEWIRE_pw_properties_set(props, PW_KEY_MEDIA_ROLE, stream_role);
     PIPEWIRE_pw_properties_set(props, PW_KEY_APP_NAME, app_name);
-    if (app_id != NULL) {
+    if (app_id) {
         PIPEWIRE_pw_properties_set(props, PW_KEY_APP_ID, app_id);
     }
     PIPEWIRE_pw_properties_set(props, PW_KEY_NODE_NAME, stream_name);
@@ -1165,7 +1165,7 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
 
             PIPEWIRE_pw_thread_loop_lock(hotplug_loop);
             node = io_list_get_by_id(node_id);
-            if (node != NULL) {
+            if (node) {
                 PIPEWIRE_pw_properties_set(props, PW_KEY_TARGET_OBJECT, node->path);
             }
             PIPEWIRE_pw_thread_loop_unlock(hotplug_loop);
@@ -1177,7 +1177,7 @@ static int PIPEWIRE_OpenDevice(SDL_AudioDevice *device)
     // Create the new stream
     priv->stream = PIPEWIRE_pw_stream_new_simple(PIPEWIRE_pw_thread_loop_get_loop(priv->loop), stream_name, props,
                                                  iscapture ? &stream_input_events : &stream_output_events, device);
-    if (priv->stream == NULL) {
+    if (!priv->stream) {
         return SDL_SetError("Pipewire: Failed to create stream (%i)", errno);
     }
 

src/audio/ps2/SDL_ps2audio.c

@@ -30,7 +30,7 @@
 static int PS2AUDIO_OpenDevice(SDL_AudioDevice *device)
 {
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -73,7 +73,7 @@ static int PS2AUDIO_OpenDevice(SDL_AudioDevice *device)
        64, so spec->size should be a multiple of 64 as well. */
     const int mixlen = device->buffer_size * NUM_BUFFERS;
     device->hidden->rawbuf = (Uint8 *)SDL_aligned_alloc(64, mixlen);
-    if (device->hidden->rawbuf == NULL) {
+    if (!device->hidden->rawbuf) {
         return SDL_SetError("Couldn't allocate mixing buffer");
     }
 
@@ -112,7 +112,7 @@ static void PS2AUDIO_CloseDevice(SDL_AudioDevice *device)
             device->hidden->channel = -1;
         }
 
-        if (device->hidden->rawbuf != NULL) {
+        if (device->hidden->rawbuf) {
             SDL_aligned_free(device->hidden->rawbuf);
             device->hidden->rawbuf = NULL;
         }

src/audio/psp/SDL_pspaudio.c

@@ -41,7 +41,7 @@ static inline SDL_bool isBasicAudioConfig(const SDL_AudioSpec *spec)
 static int PSPAUDIO_OpenDevice(SDL_AudioDevice *device)
 {
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -93,7 +93,7 @@ static int PSPAUDIO_OpenDevice(SDL_AudioDevice *device)
        64, so spec->size should be a multiple of 64 as well. */
     const int mixlen = device->buffer_size * NUM_BUFFERS;
     device->hidden->rawbuf = (Uint8 *)SDL_aligned_alloc(64, mixlen);
-    if (device->hidden->rawbuf == NULL) {
+    if (!device->hidden->rawbuf) {
         return SDL_SetError("Couldn't allocate mixing buffer");
     }
 
@@ -141,7 +141,7 @@ static void PSPAUDIO_CloseDevice(SDL_AudioDevice *device)
             device->hidden->channel = -1;
         }
 
-        if (device->hidden->rawbuf != NULL) {
+        if (device->hidden->rawbuf) {
             SDL_aligned_free(device->hidden->rawbuf);
             device->hidden->rawbuf = NULL;
         }

src/audio/pulseaudio/SDL_pulseaudio.c

@@ -135,7 +135,7 @@ static void *pulseaudio_handle = NULL;
 static int load_pulseaudio_sym(const char *fn, void **addr)
 {
     *addr = SDL_LoadFunction(pulseaudio_handle, fn);
-    if (*addr == NULL) {
+    if (!*addr) {
         // Don't call SDL_SetError(): SDL_LoadFunction already did.
         return 0;
     }
@@ -150,7 +150,7 @@ static int load_pulseaudio_sym(const char *fn, void **addr)
 
 static void UnloadPulseAudioLibrary(void)
 {
-    if (pulseaudio_handle != NULL) {
+    if (pulseaudio_handle) {
         SDL_UnloadObject(pulseaudio_handle);
         pulseaudio_handle = NULL;
     }
@@ -159,9 +159,9 @@ static void UnloadPulseAudioLibrary(void)
 static int LoadPulseAudioLibrary(void)
 {
     int retval = 0;
-    if (pulseaudio_handle == NULL) {
+    if (!pulseaudio_handle) {
         pulseaudio_handle = SDL_LoadObject(pulseaudio_library);
-        if (pulseaudio_handle == NULL) {
+        if (!pulseaudio_handle) {
             retval = -1;
             // Don't call SDL_SetError(): SDL_LoadObject already did.
         } else {
@@ -275,7 +275,7 @@ static const char *getAppName(void)
     } else {
         const char *verstr = PULSEAUDIO_pa_get_library_version();
         retval = "SDL Application"; // the "oh well" default.
-        if (verstr != NULL) {
+        if (verstr) {
             int maj, min, patch;
             if (SDL_sscanf(verstr, "%d.%d.%d", &maj, &min, &patch) == 3) {
                 if (squashVersion(maj, min, patch) >= squashVersion(0, 9, 15)) {
@@ -297,13 +297,13 @@ static void OperationStateChangeCallback(pa_operation *o, void *userdata)
 static void WaitForPulseOperation(pa_operation *o)
 {
     // This checks for NO errors currently. Either fix that, check results elsewhere, or do things you don't care about.
-    SDL_assert(pulseaudio_threaded_mainloop != NULL);
+    SDL_assert(pulseaudio_threaded_mainloop);
     if (o) {
         // note that if PULSEAUDIO_pa_operation_set_state_callback == NULL, then `o` must have a callback that will signal pulseaudio_threaded_mainloop.
         // If not, on really old (earlier PulseAudio 4.0, from the year 2013!) installs, this call will block forever.
         // On more modern installs, we won't ever block forever, and maybe be more efficient, thanks to pa_operation_set_state_callback.
         // WARNING: at the time of this writing: the Steam Runtime is still on PulseAudio 1.1!
-        if (PULSEAUDIO_pa_operation_set_state_callback != NULL) {
+        if (PULSEAUDIO_pa_operation_set_state_callback) {
             PULSEAUDIO_pa_operation_set_state_callback(o, OperationStateChangeCallback, NULL);
         }
         while (PULSEAUDIO_pa_operation_get_state(o) == PA_OPERATION_RUNNING) {
@@ -315,7 +315,7 @@ static void WaitForPulseOperation(pa_operation *o)
 
 static void DisconnectFromPulseServer(void)
 {
-    if (pulseaudio_threaded_mainloop != NULL) {
+    if (pulseaudio_threaded_mainloop) {
         PULSEAUDIO_pa_threaded_mainloop_stop(pulseaudio_threaded_mainloop);
     }
     if (pulseaudio_context) {
@@ -323,7 +323,7 @@ static void DisconnectFromPulseServer(void)
         PULSEAUDIO_pa_context_unref(pulseaudio_context);
         pulseaudio_context = NULL;
     }
-    if (pulseaudio_threaded_mainloop != NULL) {
+    if (pulseaudio_threaded_mainloop) {
         PULSEAUDIO_pa_threaded_mainloop_free(pulseaudio_threaded_mainloop);
         pulseaudio_threaded_mainloop = NULL;
     }
@@ -339,8 +339,8 @@ static int ConnectToPulseServer(void)
     pa_mainloop_api *mainloop_api = NULL;
     int state = 0;
 
-    SDL_assert(pulseaudio_threaded_mainloop == NULL);
-    SDL_assert(pulseaudio_context == NULL);
+    SDL_assert(!pulseaudio_threaded_mainloop);
+    SDL_assert(!pulseaudio_context);
 
     // Set up a new main loop
     if (!(pulseaudio_threaded_mainloop = PULSEAUDIO_pa_threaded_mainloop_new())) {
@@ -363,7 +363,7 @@ static int ConnectToPulseServer(void)
     SDL_assert(mainloop_api); // this never fails, right?
 
     pulseaudio_context = PULSEAUDIO_pa_context_new(mainloop_api, getAppName());
-    if (pulseaudio_context == NULL) {
+    if (!pulseaudio_context) {
         SDL_SetError("pa_context_new() failed");
         goto failed;
     }
@@ -480,7 +480,7 @@ static int PULSEAUDIO_WaitCaptureDevice(SDL_AudioDevice *device)
 {
     struct SDL_PrivateAudioData *h = device->hidden;
 
-    if (h->capturebuf != NULL) {
+    if (h->capturebuf) {
         return 0;  // there's still data available to read.
     }
 
@@ -500,7 +500,7 @@ static int PULSEAUDIO_WaitCaptureDevice(SDL_AudioDevice *device)
             size_t nbytes = 0;
             PULSEAUDIO_pa_stream_peek(h->stream, &data, &nbytes);
             SDL_assert(nbytes > 0);
-            if (data == NULL) {  // If NULL, then the buffer had a hole, ignore that
+            if (!data) {  // If NULL, then the buffer had a hole, ignore that
                 PULSEAUDIO_pa_stream_drop(h->stream);  // drop this fragment.
             } else {
                 // store this fragment's data for use with CaptureFromDevice
@@ -521,7 +521,7 @@ static int PULSEAUDIO_CaptureFromDevice(SDL_AudioDevice *device, void *buffer, i
 {
     struct SDL_PrivateAudioData *h = device->hidden;
 
-    if (h->capturebuf != NULL) {
+    if (h->capturebuf) {
         const int cpy = SDL_min(buflen, h->capturelen);
         if (cpy > 0) {
             //SDL_Log("PULSEAUDIO: fed %d captured bytes", cpy);
@@ -549,7 +549,7 @@ static void PULSEAUDIO_FlushCapture(SDL_AudioDevice *device)
 
     PULSEAUDIO_pa_threaded_mainloop_lock(pulseaudio_threaded_mainloop);
 
-    if (h->capturebuf != NULL) {
+    if (h->capturebuf) {
         PULSEAUDIO_pa_stream_drop(h->stream);
         h->capturebuf = NULL;
         h->capturelen = 0;
@@ -578,7 +578,7 @@ static void PULSEAUDIO_CloseDevice(SDL_AudioDevice *device)
     PULSEAUDIO_pa_threaded_mainloop_lock(pulseaudio_threaded_mainloop);
 
     if (device->hidden->stream) {
-        if (device->hidden->capturebuf != NULL) {
+        if (device->hidden->capturebuf) {
             PULSEAUDIO_pa_stream_drop(device->hidden->stream);
         }
         PULSEAUDIO_pa_stream_disconnect(device->hidden->stream);
@@ -609,12 +609,12 @@ static int PULSEAUDIO_OpenDevice(SDL_AudioDevice *device)
     int format = PA_SAMPLE_INVALID;
     int retval = 0;
 
-    SDL_assert(pulseaudio_threaded_mainloop != NULL);
-    SDL_assert(pulseaudio_context != NULL);
+    SDL_assert(pulseaudio_threaded_mainloop);
+    SDL_assert(pulseaudio_context);
 
     // Initialize all variables that we clean on shutdown
     h = device->hidden = (struct SDL_PrivateAudioData *)SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -663,7 +663,7 @@ static int PULSEAUDIO_OpenDevice(SDL_AudioDevice *device)
     // Allocate mixing buffer
     if (!iscapture) {
         h->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-        if (h->mixbuf == NULL) {
+        if (!h->mixbuf) {
             return SDL_OutOfMemory();
         }
         SDL_memset(h->mixbuf, device->silence_value, device->buffer_size);
@@ -694,7 +694,7 @@ static int PULSEAUDIO_OpenDevice(SDL_AudioDevice *device)
         &pacmap                                  // channel map
     );
 
-    if (h->stream == NULL) {
+    if (!h->stream) {
         retval = SDL_SetError("Could not set up PulseAudio stream");
     } else {
         int rc;

src/audio/qnx/SDL_qsa_audio.c

@@ -176,7 +176,7 @@ static Uint8 *QSA_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
 static void QSA_CloseDevice(SDL_AudioDevice *device)
 {
     if (device->hidden) {
-        if (device->hidden->audio_handle != NULL) {
+        if (device->hidden->audio_handle) {
             #if _NTO_VERSION < 710
             // Finish playing available samples or cancel unread samples during capture
             snd_pcm_plugin_flush(device->hidden->audio_handle, device->iscapture ? SND_PCM_CHANNEL_CAPTURE : SND_PCM_CHANNEL_PLAYBACK);

src/audio/sndio/SDL_sndioaudio.c

@@ -71,7 +71,7 @@ static void *sndio_handle = NULL;
 static int load_sndio_sym(const char *fn, void **addr)
 {
     *addr = SDL_LoadFunction(sndio_handle, fn);
-    if (*addr == NULL) {
+    if (!*addr) {
         return 0;  // Don't call SDL_SetError(): SDL_LoadFunction already did.
     }
 
@@ -110,7 +110,7 @@ static int load_sndio_syms(void)
 
 static void UnloadSNDIOLibrary(void)
 {
-    if (sndio_handle != NULL) {
+    if (sndio_handle) {
         SDL_UnloadObject(sndio_handle);
         sndio_handle = NULL;
     }
@@ -119,9 +119,9 @@ static void UnloadSNDIOLibrary(void)
 static int LoadSNDIOLibrary(void)
 {
     int retval = 0;
-    if (sndio_handle == NULL) {
+    if (!sndio_handle) {
         sndio_handle = SDL_LoadObject(sndio_library);
-        if (sndio_handle == NULL) {
+        if (!sndio_handle) {
             retval = -1;  // Don't call SDL_SetError(): SDL_LoadObject already did.
         } else {
             retval = load_sndio_syms();
@@ -213,7 +213,7 @@ static Uint8 *SNDIO_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
 static void SNDIO_CloseDevice(SDL_AudioDevice *device)
 {
     if (device->hidden) {
-        if (device->hidden->dev != NULL) {
+        if (device->hidden->dev) {
             SNDIO_sio_stop(device->hidden->dev);
             SNDIO_sio_close(device->hidden->dev);
         }
@@ -227,7 +227,7 @@ static void SNDIO_CloseDevice(SDL_AudioDevice *device)
 static int SNDIO_OpenDevice(SDL_AudioDevice *device)
 {
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
 
@@ -235,14 +235,14 @@ static int SNDIO_OpenDevice(SDL_AudioDevice *device)
     const char *audiodev = SDL_getenv("AUDIODEV");
 
     // Capture devices must be non-blocking for SNDIO_FlushCapture
-    device->hidden->dev = SNDIO_sio_open(audiodev != NULL ? audiodev : SIO_DEVANY,
+    device->hidden->dev = SNDIO_sio_open(audiodev ? audiodev : SIO_DEVANY,
                                          device->iscapture ? SIO_REC : SIO_PLAY, device->iscapture);
-    if (device->hidden->dev == NULL) {
+    if (!device->hidden->dev) {
         return SDL_SetError("sio_open() failed");
     }
 
     device->hidden->pfd = SDL_malloc(sizeof(struct pollfd) * SNDIO_sio_nfds(device->hidden->dev));
-    if (device->hidden->pfd == NULL) {
+    if (!device->hidden->pfd) {
         return SDL_OutOfMemory();
     }
 
@@ -307,7 +307,7 @@ static int SNDIO_OpenDevice(SDL_AudioDevice *device)
 
     // Allocate mixing buffer
     device->hidden->mixbuf = (Uint8 *)SDL_malloc(device->buffer_size);
-    if (device->hidden->mixbuf == NULL) {
+    if (!device->hidden->mixbuf) {
         return SDL_OutOfMemory();
     }
     SDL_memset(device->hidden->mixbuf, device->silence_value, device->buffer_size);

src/audio/vita/SDL_vitaaudio.c

@@ -63,7 +63,7 @@ static int VITAAUD_OpenDevice(SDL_AudioDevice *device)
 
     device->hidden = (struct SDL_PrivateAudioData *)
         SDL_malloc(sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     }
     SDL_memset(device->hidden, 0, sizeof(*device->hidden));
@@ -95,7 +95,7 @@ static int VITAAUD_OpenDevice(SDL_AudioDevice *device)
        64, so spec->size should be a multiple of 64 as well. */
     mixlen = device->buffer_size * NUM_BUFFERS;
     device->hidden->rawbuf = (Uint8 *)SDL_aligned_alloc(64, mixlen);
-    if (device->hidden->rawbuf == NULL) {
+    if (!device->hidden->rawbuf) {
         return SDL_SetError("Couldn't allocate mixing buffer");
     }
 
@@ -163,7 +163,7 @@ static void VITAAUD_CloseDevice(SDL_AudioDevice *device)
             device->hidden->port = -1;
         }
 
-        if (!device->iscapture && device->hidden->rawbuf != NULL) {
+        if (!device->iscapture && device->hidden->rawbuf) {
             SDL_aligned_free(device->hidden->rawbuf); // this uses SDL_aligned_alloc(), not SDL_malloc()
             device->hidden->rawbuf = NULL;
         }

src/audio/wasapi/SDL_wasapi.c

@@ -93,7 +93,7 @@ static void ManagementThreadMainloop(void)
 int WASAPI_ProxyToManagementThread(ManagementThreadTask task, void *userdata, int *wait_on_result)
 {
     // We want to block for a result, but we are already running from the management thread! Just run the task now so we don't deadlock.
-    if ((wait_on_result != NULL) && (SDL_ThreadID() == SDL_GetThreadID(ManagementThread))) {
+    if ((wait_on_result) && (SDL_ThreadID() == SDL_GetThreadID(ManagementThread))) {
         *wait_on_result = task(userdata);
         return 0;  // completed!
     }
@@ -124,11 +124,11 @@ int WASAPI_ProxyToManagementThread(ManagementThreadTask task, void *userdata, in
 
     // add to end of task list.
     ManagementThreadPendingTask *prev = NULL;
-    for (ManagementThreadPendingTask *i = SDL_AtomicGetPtr((void **) &ManagementThreadPendingTasks); i != NULL; i = i->next) {
+    for (ManagementThreadPendingTask *i = SDL_AtomicGetPtr((void **) &ManagementThreadPendingTasks); i; i = i->next) {
         prev = i;
     }
 
-    if (prev != NULL) {
+    if (prev) {
         prev->next = pending;
     } else {
         SDL_AtomicSetPtr((void **) &ManagementThreadPendingTasks, pending);
@@ -413,7 +413,7 @@ static Uint8 *WASAPI_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
 
     if (device->hidden->render) {
         if (WasapiFailed(device, IAudioRenderClient_GetBuffer(device->hidden->render, device->sample_frames, &buffer))) {
-            SDL_assert(buffer == NULL);
+            SDL_assert(!buffer);
             if (device->hidden->device_lost) {  // just use an available buffer, we won't be playing it anyhow.
                 *buffer_size = 0;  // we'll recover during WaitDevice and try again.
             }
@@ -425,7 +425,7 @@ static Uint8 *WASAPI_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
 
 static int WASAPI_PlayDevice(SDL_AudioDevice *device, const Uint8 *buffer, int buflen)
 {
-    if (device->hidden->render != NULL) { // definitely activated?
+    if (device->hidden->render) { // definitely activated?
         // WasapiFailed() will mark the device for reacquisition or removal elsewhere.
         WasapiFailed(device, IAudioRenderClient_ReleaseBuffer(device->hidden->render, device->sample_frames, 0));
     }
@@ -542,7 +542,7 @@ static int mgmtthrtask_PrepDevice(void *userdata)
     const AUDCLNT_SHAREMODE sharemode = AUDCLNT_SHAREMODE_SHARED;
 
     IAudioClient *client = device->hidden->client;
-    SDL_assert(client != NULL);
+    SDL_assert(client);
 
 #if defined(__WINRT__) || defined(__GDK__) // CreateEventEx() arrived in Vista, so we need an #ifdef for XP.
     device->hidden->event = CreateEventEx(NULL, NULL, 0, EVENT_ALL_ACCESS);
@@ -550,7 +550,7 @@ static int mgmtthrtask_PrepDevice(void *userdata)
     device->hidden->event = CreateEventW(NULL, 0, 0, NULL);
 #endif
 
-    if (device->hidden->event == NULL) {
+    if (!device->hidden->event) {
         return WIN_SetError("WASAPI can't create an event handle");
     }
 
@@ -561,7 +561,7 @@ static int mgmtthrtask_PrepDevice(void *userdata)
     if (FAILED(ret)) {
         return WIN_SetErrorFromHRESULT("WASAPI can't determine mix format", ret);
     }
-    SDL_assert(waveformat != NULL);
+    SDL_assert(waveformat);
     device->hidden->waveformat = waveformat;
 
     SDL_AudioSpec newspec;
@@ -642,7 +642,7 @@ static int mgmtthrtask_PrepDevice(void *userdata)
             return WIN_SetErrorFromHRESULT("WASAPI can't get capture client service", ret);
         }
 
-        SDL_assert(capture != NULL);
+        SDL_assert(capture);
         device->hidden->capture = capture;
         ret = IAudioClient_Start(client);
         if (FAILED(ret)) {
@@ -657,7 +657,7 @@ static int mgmtthrtask_PrepDevice(void *userdata)
             return WIN_SetErrorFromHRESULT("WASAPI can't get render client service", ret);
         }
 
-        SDL_assert(render != NULL);
+        SDL_assert(render);
         device->hidden->render = render;
         ret = IAudioClient_Start(client);
         if (FAILED(ret)) {
@@ -679,7 +679,7 @@ static int WASAPI_OpenDevice(SDL_AudioDevice *device)
 {
     // Initialize all variables that we clean on shutdown
     device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
-    if (device->hidden == NULL) {
+    if (!device->hidden) {
         return SDL_OutOfMemory();
     } else if (ActivateWasapiDevice(device) < 0) {
         return -1; // already set error.

src/audio/wasapi/SDL_wasapi_win32.c

@@ -164,11 +164,11 @@ int WASAPI_ActivateDevice(SDL_AudioDevice *device)
     IMMDevice_Release(immdevice);
 
     if (FAILED(ret)) {
-        SDL_assert(device->hidden->client == NULL);
+        SDL_assert(!device->hidden->client);
         return WIN_SetErrorFromHRESULT("WASAPI can't activate audio endpoint", ret);
     }
 
-    SDL_assert(device->hidden->client != NULL);
+    SDL_assert(device->hidden->client);
     if (WASAPI_PrepDevice(device) == -1) { // not async, fire it right away.
         return -1;
     }

src/core/SDL_runapp.c

@@ -32,7 +32,7 @@ SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserved)
 
     (void)reserved;
 
-    if(argv == NULL)
+    if(!argv)
     {
         argc = 0;
         /* make sure argv isn't NULL, in case some user code doesn't like that */

src/core/android/SDL_android.c

@@ -434,12 +434,12 @@ JNIEnv *Android_JNI_GetEnv(void)
 {
     /* Get JNIEnv from the Thread local storage */
     JNIEnv *env = pthread_getspecific(mThreadKey);
-    if (env == NULL) {
+    if (!env) {
         /* If it fails, try to attach ! (e.g the thread isn't created with SDL_CreateThread() */
         int status;
 
         /* There should be a JVM */
-        if (mJavaVM == NULL) {
+        if (!mJavaVM) {
             __android_log_print(ANDROID_LOG_ERROR, "SDL", "Failed, there is no JavaVM");
             return NULL;
         }
@@ -468,7 +468,7 @@ int Android_JNI_SetupThread(void)
     int status;
 
     /* There should be a JVM */
-    if (mJavaVM == NULL) {
+    if (!mJavaVM) {
         __android_log_print(ANDROID_LOG_ERROR, "SDL", "Failed, there is no JavaVM");
         return 0;
     }
@@ -494,7 +494,7 @@ static void Android_JNI_ThreadDestroyed(void *value)
 {
     /* The thread is being destroyed, detach it from the Java VM and set the mThreadKey value to NULL as required */
     JNIEnv *env = (JNIEnv *)value;
-    if (env != NULL) {
+    if (env) {
         (*mJavaVM)->DetachCurrentThread(mJavaVM);
         Android_JNI_SetEnv(NULL);
     }
@@ -520,7 +520,7 @@ static void Android_JNI_CreateKey_once(void)
 static void register_methods(JNIEnv *env, const char *classname, JNINativeMethod *methods, int nb)
 {
     jclass clazz = (*env)->FindClass(env, classname);
-    if (clazz == NULL || (*env)->RegisterNatives(env, clazz, methods, nb) < 0) {
+    if (!clazz || (*env)->RegisterNatives(env, clazz, methods, nb) < 0) {
         __android_log_print(ANDROID_LOG_ERROR, "SDL", "Failed to register methods of %s", classname);
         return;
     }
@@ -582,28 +582,28 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
     /* Save JNIEnv of SDLActivity */
     Android_JNI_SetEnv(env);
 
-    if (mJavaVM == NULL) {
+    if (!mJavaVM) {
         __android_log_print(ANDROID_LOG_ERROR, "SDL", "failed to found a JavaVM");
     }
 
     /* Use a mutex to prevent concurrency issues between Java Activity and Native thread code, when using 'Android_Window'.
      * (Eg. Java sending Touch events, while native code is destroying the main SDL_Window. )
      */
-    if (Android_ActivityMutex == NULL) {
+    if (!Android_ActivityMutex) {
         Android_ActivityMutex = SDL_CreateMutex(); /* Could this be created twice if onCreate() is called a second time ? */
     }
 
-    if (Android_ActivityMutex == NULL) {
+    if (!Android_ActivityMutex) {
         __android_log_print(ANDROID_LOG_ERROR, "SDL", "failed to create Android_ActivityMutex mutex");
     }
 
     Android_PauseSem = SDL_CreateSemaphore(0);
-    if (Android_PauseSem == NULL) {
+    if (!Android_PauseSem) {
         __android_log_print(ANDROID_LOG_ERROR, "SDL", "failed to create Android_PauseSem semaphore");
     }
 
     Android_ResumeSem = SDL_CreateSemaphore(0);
-    if (Android_ResumeSem == NULL) {
+    if (!Android_ResumeSem) {
         __android_log_print(ANDROID_LOG_ERROR, "SDL", "failed to create Android_ResumeSem semaphore");
     }
 
@@ -1614,7 +1614,7 @@ int Android_JNI_OpenAudioDevice(SDL_AudioDevice *device)
         __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "SDL audio: opening device for output");
         result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midAudioOpen, spec->freq, audioformat, spec->channels, device->sample_frames, device_id);
     }
-    if (result == NULL) {
+    if (!result) {
         /* Error during audio initialization, error printed from Java */
         return SDL_SetError("Java-side initialization failed");
     }
@@ -1675,7 +1675,7 @@ int Android_JNI_OpenAudioDevice(SDL_AudioDevice *device)
         return SDL_SetError("Unexpected audio format from Java: %d\n", audioformat);
     }
 
-    if (jbufobj == NULL) {
+    if (!jbufobj) {
         __android_log_print(ANDROID_LOG_WARN, "SDL", "SDL audio: could not allocate an audio buffer");
         return SDL_OutOfMemory();
     }
@@ -1946,7 +1946,7 @@ static void Internal_Android_Create_AssetManager()
     javaAssetManagerRef = (*env)->NewGlobalRef(env, javaAssetManager);
     asset_manager = AAssetManager_fromJava(env, javaAssetManagerRef);
 
-    if (asset_manager == NULL) {
+    if (!asset_manager) {
         (*env)->DeleteGlobalRef(env, javaAssetManagerRef);
         Android_JNI_ExceptionOccurred(SDL_TRUE);
     }
@@ -1970,16 +1970,16 @@ int Android_JNI_FileOpen(SDL_RWops *ctx,
     AAsset *asset = NULL;
     ctx->hidden.androidio.asset = NULL;
 
-    if (asset_manager == NULL) {
+    if (!asset_manager) {
         Internal_Android_Create_AssetManager();
     }
 
-    if (asset_manager == NULL) {
+    if (!asset_manager) {
         return SDL_SetError("Couldn't create asset manager");
     }
 
     asset = AAssetManager_open(asset_manager, fileName, AASSET_MODE_UNKNOWN);
-    if (asset == NULL) {
+    if (!asset) {
         return SDL_SetError("Couldn't open asset '%s'", fileName);
     }
 
@@ -2051,7 +2051,7 @@ char *Android_JNI_GetClipboardText(void)
         (*env)->DeleteLocalRef(env, string);
     }
 
-    return (text == NULL) ? SDL_strdup("") : text;
+    return (!text) ? SDL_strdup("") : text;
 }
 
 SDL_bool Android_JNI_HasClipboardText(void)
@@ -2371,7 +2371,7 @@ void *SDL_AndroidGetActivity(void)
     /* See SDL_system.h for caveats on using this function. */
 
     JNIEnv *env = Android_JNI_GetEnv();
-    if (env == NULL) {
+    if (!env) {
         return NULL;
     }
 
@@ -2425,7 +2425,7 @@ const char *SDL_AndroidGetInternalStoragePath(void)
 {
     static char *s_AndroidInternalFilesPath = NULL;
 
-    if (s_AndroidInternalFilesPath == NULL) {
+    if (!s_AndroidInternalFilesPath) {
         struct LocalReferenceHolder refs = LocalReferenceHolder_Setup(__FUNCTION__);
         jmethodID mid;
         jobject context;
@@ -2524,7 +2524,7 @@ const char *SDL_AndroidGetExternalStoragePath(void)
 {
     static char *s_AndroidExternalFilesPath = NULL;
 
-    if (s_AndroidExternalFilesPath == NULL) {
+    if (!s_AndroidExternalFilesPath) {
         struct LocalReferenceHolder refs = LocalReferenceHolder_Setup(__FUNCTION__);
         jmethodID mid;
         jobject context;
@@ -2680,16 +2680,16 @@ int Android_JNI_GetLocale(char *buf, size_t buflen)
     /* Need to re-create the asset manager if locale has changed (SDL_EVENT_LOCALE_CHANGED) */
     Internal_Android_Destroy_AssetManager();
 
-    if (asset_manager == NULL) {
+    if (!asset_manager) {
         Internal_Android_Create_AssetManager();
     }
 
-    if (asset_manager == NULL) {
+    if (!asset_manager) {
         return -1;
     }
 
     cfg = AConfiguration_new();
-    if (cfg == NULL) {
+    if (!cfg) {
         return -1;
     }
 

src/core/freebsd/SDL_evdev_kbd_freebsd.c

@@ -87,7 +87,7 @@ static void kbd_cleanup(void)
 {
     struct mouse_info mData;
     SDL_EVDEV_keyboard_state *kbd = kbd_cleanup_state;
-    if (kbd == NULL) {
+    if (!kbd) {
         return;
     }
     kbd_cleanup_state = NULL;
@@ -178,7 +178,7 @@ static void kbd_register_emerg_cleanup(SDL_EVDEV_keyboard_state *kbd)
 {
     int tabidx;
 
-    if (kbd_cleanup_state != NULL) {
+    if (kbd_cleanup_state) {
         return;
     }
     kbd_cleanup_state = kbd;
@@ -230,7 +230,7 @@ SDL_EVDEV_keyboard_state *SDL_EVDEV_kbd_init(void)
     SDL_zero(mData);
     mData.operation = MOUSE_HIDE;
     kbd = (SDL_EVDEV_keyboard_state *)SDL_calloc(1, sizeof(SDL_EVDEV_keyboard_state));
-    if (kbd == NULL) {
+    if (!kbd) {
         return NULL;
     }
 
@@ -296,7 +296,7 @@ void SDL_EVDEV_kbd_quit(SDL_EVDEV_keyboard_state *kbd)
 {
     struct mouse_info mData;
 
-    if (kbd == NULL) {
+    if (!kbd) {
         return;
     }
     SDL_zero(mData);
@@ -486,7 +486,7 @@ void SDL_EVDEV_kbd_keycode(SDL_EVDEV_keyboard_state *kbd, unsigned int keycode,
     unsigned int final_key_state;
     unsigned int map_from_key_sym;
 
-    if (kbd == NULL) {
+    if (!kbd) {
         return;
     }
 

src/core/haiku/SDL_BeApp.cc

@@ -108,13 +108,13 @@ static int StartBeLooper()
 {
     if (!be_app) {
         SDL_AppThread = SDL_CreateThreadInternal(StartBeApp, "SDLApplication", 0, NULL);
-        if (SDL_AppThread == NULL) {
+        if (!SDL_AppThread) {
             return SDL_SetError("Couldn't create BApplication thread");
         }
 
         do {
             SDL_Delay(10);
-        } while ((be_app == NULL) || be_app->IsLaunching());
+        } while ((!be_app) || be_app->IsLaunching());
     }
 
      /* Change working directory to that of executable */
@@ -167,7 +167,7 @@ void SDL_QuitBeApp(void)
         SDL_Looper->Lock();
         SDL_Looper->Quit();
         SDL_Looper = NULL;
-        if (SDL_AppThread != NULL) {
+        if (SDL_AppThread) {
             if (be_app != NULL) {       /* Not tested */
                 be_app->PostMessage(B_QUIT_REQUESTED);
             }

src/core/linux/SDL_dbus.c

@@ -96,7 +96,7 @@ static int LoadDBUSSyms(void)
 
 static void UnloadDBUSLibrary(void)
 {
-    if (dbus_handle != NULL) {
+    if (dbus_handle) {
         SDL_UnloadObject(dbus_handle);
         dbus_handle = NULL;
     }
@@ -105,9 +105,9 @@ static void UnloadDBUSLibrary(void)
 static int LoadDBUSLibrary(void)
 {
     int retval = 0;
-    if (dbus_handle == NULL) {
+    if (!dbus_handle) {
         dbus_handle = SDL_LoadObject(dbus_library);
-        if (dbus_handle == NULL) {
+        if (!dbus_handle) {
             retval = -1;
             /* Don't call SDL_SetError(): SDL_LoadObject already did. */
         } else {
@@ -199,7 +199,7 @@ void SDL_DBus_Quit(void)
 
 SDL_DBusContext *SDL_DBus_GetContext(void)
 {
-    if (dbus_handle == NULL || !dbus.session_conn) {
+    if (!dbus_handle || !dbus.session_conn) {
         SDL_DBus_Init();
     }
 
@@ -360,7 +360,7 @@ SDL_bool SDL_DBus_QueryProperty(const char *node, const char *path, const char *
 
 void SDL_DBus_ScreensaverTickle(void)
 {
-    if (screensaver_cookie == 0 && inhibit_handle == NULL) { /* no need to tickle if we're inhibiting. */
+    if (screensaver_cookie == 0 && !inhibit_handle) { /* no need to tickle if we're inhibiting. */
         /* org.gnome.ScreenSaver is the legacy interface, but it'll either do nothing or just be a second harmless tickle on newer systems, so we leave it for now. */
         SDL_DBus_CallVoidMethod("org.gnome.ScreenSaver", "/org/gnome/ScreenSaver", "org.gnome.ScreenSaver", "SimulateUserActivity", DBUS_TYPE_INVALID);
         SDL_DBus_CallVoidMethod("org.freedesktop.ScreenSaver", "/org/freedesktop/ScreenSaver", "org.freedesktop.ScreenSaver", "SimulateUserActivity", DBUS_TYPE_INVALID);
@@ -428,7 +428,7 @@ SDL_bool SDL_DBus_ScreensaverInhibit(SDL_bool inhibit)
 {
     const char *default_inhibit_reason = "Playing a game";
 
-    if ((inhibit && (screensaver_cookie != 0 || inhibit_handle != NULL)) || (!inhibit && (screensaver_cookie == 0 && inhibit_handle == NULL))) {
+    if ((inhibit && (screensaver_cookie != 0 || inhibit_handle)) || (!inhibit && (screensaver_cookie == 0 && !inhibit_handle))) {
         return SDL_TRUE;
     }
 
@@ -452,12 +452,12 @@ SDL_bool SDL_DBus_ScreensaverInhibit(SDL_bool inhibit)
             const char *key = "reason";
             const char *reply = NULL;
             const char *reason = SDL_GetHint(SDL_HINT_SCREENSAVER_INHIBIT_ACTIVITY_NAME);
-            if (reason == NULL || !reason[0]) {
+            if (!reason || !reason[0]) {
                 reason = default_inhibit_reason;
             }
 
             msg = dbus.message_new_method_call(bus_name, path, interface, "Inhibit");
-            if (msg == NULL) {
+            if (!msg) {
                 return SDL_FALSE;
             }
 
@@ -496,10 +496,10 @@ SDL_bool SDL_DBus_ScreensaverInhibit(SDL_bool inhibit)
         if (inhibit) {
             const char *app = SDL_GetHint(SDL_HINT_APP_NAME);
             const char *reason = SDL_GetHint(SDL_HINT_SCREENSAVER_INHIBIT_ACTIVITY_NAME);
-            if (app == NULL || !app[0]) {
+            if (!app || !app[0]) {
                 app = "My SDL application";
             }
-            if (reason == NULL || !reason[0]) {
+            if (!reason || !reason[0]) {
                 reason = default_inhibit_reason;
             }
 

src/core/linux/SDL_evdev.c

@@ -167,9 +167,9 @@ static void SDL_EVDEV_UpdateKeyboardMute(void)
 
 int SDL_EVDEV_Init(void)
 {
-    if (_this == NULL) {
+    if (!_this) {
         _this = (SDL_EVDEV_PrivateData *)SDL_calloc(1, sizeof(*_this));
-        if (_this == NULL) {
+        if (!_this) {
             return SDL_OutOfMemory();
         }
 
@@ -231,7 +231,7 @@ int SDL_EVDEV_Init(void)
 
 void SDL_EVDEV_Quit(void)
 {
-    if (_this == NULL) {
+    if (!_this) {
         return;
     }
 
@@ -244,14 +244,14 @@ void SDL_EVDEV_Quit(void)
 #endif /* SDL_USE_LIBUDEV */
 
         /* Remove existing devices */
-        while (_this->first != NULL) {
+        while (_this->first) {
             SDL_EVDEV_device_removed(_this->first->path);
         }
 
         SDL_EVDEV_kbd_quit(_this->kbd);
 
-        SDL_assert(_this->first == NULL);
-        SDL_assert(_this->last == NULL);
+        SDL_assert(!_this->first);
+        SDL_assert(!_this->last);
         SDL_assert(_this->num_devices == 0);
 
         SDL_free(_this);
@@ -263,7 +263,7 @@ void SDL_EVDEV_Quit(void)
 static void SDL_EVDEV_udev_callback(SDL_UDEV_deviceevent udev_event, int udev_class,
                                     const char *dev_path)
 {
-    if (dev_path == NULL) {
+    if (!dev_path) {
         return;
     }
 
@@ -301,7 +301,7 @@ int SDL_EVDEV_GetDeviceCount(int device_class)
     SDL_evdevlist_item *item;
     int count = 0;
 
-    for (item = _this->first; item != NULL; item = item->next) {
+    for (item = _this->first; item; item = item->next) {
         if ((item->udev_class & device_class) == device_class) {
             ++count;
         }
@@ -331,7 +331,7 @@ void SDL_EVDEV_Poll(void)
 
     mouse = SDL_GetMouse();
 
-    for (item = _this->first; item != NULL; item = item->next) {
+    for (item = _this->first; item; item = item->next) {
         while ((len = read(item->fd, events, sizeof(events))) > 0) {
             len /= sizeof(events[0]);
             for (i = 0; i < len; ++i) {
@@ -643,7 +643,7 @@ static int SDL_EVDEV_init_touchscreen(SDL_evdevlist_item *item, int udev_class)
     }
 
     item->touchscreen_data = SDL_calloc(1, sizeof(*item->touchscreen_data));
-    if (item->touchscreen_data == NULL) {
+    if (!item->touchscreen_data) {
         return SDL_OutOfMemory();
     }
 
@@ -654,7 +654,7 @@ static int SDL_EVDEV_init_touchscreen(SDL_evdevlist_item *item, int udev_class)
     }
 
     item->touchscreen_data->name = SDL_strdup(name);
-    if (item->touchscreen_data->name == NULL) {
+    if (!item->touchscreen_data->name) {
         SDL_free(item->touchscreen_data);
         return SDL_OutOfMemory();
     }
@@ -709,7 +709,7 @@ static int SDL_EVDEV_init_touchscreen(SDL_evdevlist_item *item, int udev_class)
     item->touchscreen_data->slots = SDL_calloc(
         item->touchscreen_data->max_slots,
         sizeof(*item->touchscreen_data->slots));
-    if (item->touchscreen_data->slots == NULL) {
+    if (!item->touchscreen_data->slots) {
         SDL_free(item->touchscreen_data->name);
         SDL_free(item->touchscreen_data);
         return SDL_OutOfMemory();
@@ -770,7 +770,7 @@ static void SDL_EVDEV_sync_device(SDL_evdevlist_item *item)
                   sizeof(*mt_req_values) * item->touchscreen_data->max_slots;
 
     mt_req_code = SDL_calloc(1, mt_req_size);
-    if (mt_req_code == NULL) {
+    if (!mt_req_code) {
         return;
     }
 
@@ -875,14 +875,14 @@ static int SDL_EVDEV_device_added(const char *dev_path, int udev_class)
     unsigned long relbit[NBITS(REL_MAX)] = { 0 };
 
     /* Check to make sure it's not already in list. */
-    for (item = _this->first; item != NULL; item = item->next) {
+    for (item = _this->first; item; item = item->next) {
         if (SDL_strcmp(dev_path, item->path) == 0) {
             return -1; /* already have this one */
         }
     }
 
     item = (SDL_evdevlist_item *)SDL_calloc(1, sizeof(SDL_evdevlist_item));
-    if (item == NULL) {
+    if (!item) {
         return SDL_OutOfMemory();
     }
 
@@ -893,7 +893,7 @@ static int SDL_EVDEV_device_added(const char *dev_path, int udev_class)
     }
 
     item->path = SDL_strdup(dev_path);
-    if (item->path == NULL) {
+    if (!item->path) {
         close(item->fd);
         SDL_free(item);
         return SDL_OutOfMemory();
@@ -928,7 +928,7 @@ static int SDL_EVDEV_device_added(const char *dev_path, int udev_class)
         }
     }
 
-    if (_this->last == NULL) {
+    if (!_this->last) {
         _this->first = _this->last = item;
     } else {
         _this->last->next = item;
@@ -947,10 +947,10 @@ static int SDL_EVDEV_device_removed(const char *dev_path)
     SDL_evdevlist_item *item;
     SDL_evdevlist_item *prev = NULL;
 
-    for (item = _this->first; item != NULL; item = item->next) {
+    for (item = _this->first; item; item = item->next) {
         /* found it, remove it. */
         if (SDL_strcmp(dev_path, item->path) == 0) {
-            if (prev != NULL) {
+            if (prev) {
                 prev->next = item->next;
             } else {
                 SDL_assert(_this->first == item);

src/core/linux/SDL_evdev_kbd.c

@@ -173,7 +173,7 @@ static int fatal_signals[] = {
 static void kbd_cleanup(void)
 {
     SDL_EVDEV_keyboard_state *kbd = kbd_cleanup_state;
-    if (kbd == NULL) {
+    if (!kbd) {
         return;
     }
     kbd_cleanup_state = NULL;
@@ -258,7 +258,7 @@ static void kbd_register_emerg_cleanup(SDL_EVDEV_keyboard_state *kbd)
 {
     int tabidx;
 
-    if (kbd_cleanup_state != NULL) {
+    if (kbd_cleanup_state) {
         return;
     }
     kbd_cleanup_state = kbd;
@@ -428,7 +428,7 @@ SDL_EVDEV_keyboard_state *SDL_EVDEV_kbd_init(void)
     char shift_state[sizeof(long)] = { TIOCL_GETSHIFTSTATE, 0 };
 
     kbd = (SDL_EVDEV_keyboard_state *)SDL_calloc(1, sizeof(*kbd));
-    if (kbd == NULL) {
+    if (!kbd) {
         return NULL;
     }
 
@@ -464,7 +464,7 @@ SDL_EVDEV_keyboard_state *SDL_EVDEV_kbd_init(void)
 
 void SDL_EVDEV_kbd_set_muted(SDL_EVDEV_keyboard_state *state, SDL_bool muted)
 {
-    if (state == NULL) {
+    if (!state) {
         return;
     }
 
@@ -892,7 +892,7 @@ void SDL_EVDEV_kbd_keycode(SDL_EVDEV_keyboard_state *state, unsigned int keycode
     unsigned short *key_map;
     unsigned short keysym;
 
-    if (state == NULL) {
+    if (!state) {
         return;
     }
 
@@ -900,7 +900,7 @@ void SDL_EVDEV_kbd_keycode(SDL_EVDEV_keyboard_state *state, unsigned int keycode
 
     shift_final = (state->shift_state | state->slockstate) ^ state->lockstate;
     key_map = state->key_maps[shift_final];
-    if (key_map == NULL) {
+    if (!key_map) {
         /* Unsupported shift state (e.g. ctrl = 4, alt = 8), just reset to the default state */
         state->shift_state = 0;
         state->slockstate = 0;

src/core/linux/SDL_fcitx.c

@@ -419,7 +419,7 @@ void SDL_Fcitx_UpdateTextRect(const SDL_Rect *rect)
     }
 
     focused_win = SDL_GetKeyboardFocus();
-    if (focused_win == NULL) {
+    if (!focused_win) {
         return;
     }
 

src/core/linux/SDL_ibus.c

@@ -112,7 +112,7 @@ static SDL_bool IBus_EnterVariant(DBusConnection *conn, DBusMessageIter *iter, S
     }
 
     dbus->message_iter_get_basic(inside, &struct_id);
-    if (struct_id == NULL || SDL_strncmp(struct_id, struct_id, id_size) != 0) {
+    if (!struct_id || SDL_strncmp(struct_id, struct_id, id_size) != 0) {
         return SDL_FALSE;
     }
     return SDL_TRUE;
@@ -291,7 +291,7 @@ static char *IBus_ReadAddressFromFile(const char *file_path)
     FILE *addr_file;
 
     addr_file = fopen(file_path, "r");
-    if (addr_file == NULL) {
+    if (!addr_file) {
         return NULL;
     }
 
@@ -336,7 +336,7 @@ static char *IBus_GetDBusAddressFilename(void)
     }
 
     dbus = SDL_DBus_GetContext();
-    if (dbus == NULL) {
+    if (!dbus) {
         return NULL;
     }
 
@@ -350,7 +350,7 @@ static char *IBus_GetDBusAddressFilename(void)
        and look up the address from a filepath using all those bits, eek. */
     disp_env = SDL_getenv("DISPLAY");
 
-    if (disp_env == NULL || !*disp_env) {
+    if (!disp_env || !*disp_env) {
         display = SDL_strdup(":0.0");
     } else {
         display = SDL_strdup(disp_env);
@@ -360,7 +360,7 @@ static char *IBus_GetDBusAddressFilename(void)
     disp_num = SDL_strrchr(display, ':');
     screen_num = SDL_strrchr(display, '.');
 
-    if (disp_num == NULL) {
+    if (!disp_num) {
         SDL_free(display);
         return NULL;
     }
@@ -374,7 +374,7 @@ static char *IBus_GetDBusAddressFilename(void)
 
     if (!*host) {
         const char *session = SDL_getenv("XDG_SESSION_TYPE");
-        if (session != NULL && SDL_strcmp(session, "wayland") == 0) {
+        if (session && SDL_strcmp(session, "wayland") == 0) {
             host = "unix-wayland";
         } else {
             host = "unix";
@@ -388,7 +388,7 @@ static char *IBus_GetDBusAddressFilename(void)
         SDL_strlcpy(config_dir, conf_env, sizeof(config_dir));
     } else {
         const char *home_env = SDL_getenv("HOME");
-        if (home_env == NULL || !*home_env) {
+        if (!home_env || !*home_env) {
             SDL_free(display);
             return NULL;
         }
@@ -397,7 +397,7 @@ static char *IBus_GetDBusAddressFilename(void)
 
     key = SDL_DBus_GetLocalMachineId();
 
-    if (key == NULL) {
+    if (!key) {
         SDL_free(display);
         return NULL;
     }
@@ -458,7 +458,7 @@ static SDL_bool IBus_SetupConnection(SDL_DBusContext *dbus, const char *addr)
         ibus_input_interface = IBUS_INPUT_INTERFACE;
         ibus_conn = dbus->connection_open_private(addr, NULL);
 
-        if (ibus_conn == NULL) {
+        if (!ibus_conn) {
             return SDL_FALSE; /* oh well. */
         }
 
@@ -498,7 +498,7 @@ static SDL_bool IBus_SetupConnection(SDL_DBusContext *dbus, const char *addr)
 
 static SDL_bool IBus_CheckConnection(SDL_DBusContext *dbus)
 {
-    if (dbus == NULL) {
+    if (!dbus) {
         return SDL_FALSE;
     }
 
@@ -518,7 +518,7 @@ static SDL_bool IBus_CheckConnection(SDL_DBusContext *dbus)
                 struct inotify_event *event = (struct inotify_event *)p;
                 if (event->len > 0) {
                     char *addr_file_no_path = SDL_strrchr(ibus_addr_file, '/');
-                    if (addr_file_no_path == NULL) {
+                    if (!addr_file_no_path) {
                         return SDL_FALSE;
                     }
 
@@ -555,12 +555,12 @@ SDL_bool SDL_IBus_Init(void)
         char *addr;
         char *addr_file_dir;
 
-        if (addr_file == NULL) {
+        if (!addr_file) {
             return SDL_FALSE;
         }
 
         addr = IBus_ReadAddressFromFile(addr_file);
-        if (addr == NULL) {
+        if (!addr) {
             SDL_free(addr_file);
             return SDL_FALSE;
         }
@@ -646,7 +646,7 @@ static void IBus_SimpleMessage(const char *method)
 {
     SDL_DBusContext *dbus = SDL_DBus_GetContext();
 
-    if ((input_ctx_path != NULL) && (IBus_CheckConnection(dbus))) {
+    if ((input_ctx_path) && (IBus_CheckConnection(dbus))) {
         SDL_DBus_CallVoidMethodOnConnection(ibus_conn, ibus_service, input_ctx_path, ibus_input_interface, method, DBUS_TYPE_INVALID);
     }
 }
@@ -696,7 +696,7 @@ void SDL_IBus_UpdateTextRect(const SDL_Rect *rect)
     }
 
     focused_win = SDL_GetKeyboardFocus();
-    if (focused_win == NULL) {
+    if (!focused_win) {
         return;
     }
 

src/core/linux/SDL_ime.c

@@ -56,9 +56,9 @@ static void InitIME(void)
 
     /* See if fcitx IME support is being requested */
 #ifdef HAVE_FCITX
-    if (SDL_IME_Init_Real == NULL &&
+    if (!SDL_IME_Init_Real &&
         ((im_module && SDL_strcmp(im_module, "fcitx") == 0) ||
-         (im_module == NULL && xmodifiers && SDL_strstr(xmodifiers, "@im=fcitx") != NULL))) {
+         (!im_module && xmodifiers && SDL_strstr(xmodifiers, "@im=fcitx") != NULL))) {
         SDL_IME_Init_Real = SDL_Fcitx_Init;
         SDL_IME_Quit_Real = SDL_Fcitx_Quit;
         SDL_IME_SetFocus_Real = SDL_Fcitx_SetFocus;
@@ -71,7 +71,7 @@ static void InitIME(void)
 
     /* default to IBus */
 #ifdef HAVE_IBUS_IBUS_H
-    if (SDL_IME_Init_Real == NULL) {
+    if (!SDL_IME_Init_Real) {
         SDL_IME_Init_Real = SDL_IBus_Init;
         SDL_IME_Quit_Real = SDL_IBus_Quit;
         SDL_IME_SetFocus_Real = SDL_IBus_SetFocus;

src/core/linux/SDL_system_theme.c

@@ -115,12 +115,12 @@ SDL_bool SDL_SystemTheme_Init(void)
 
     system_theme_data.theme = SDL_SYSTEM_THEME_UNKNOWN;
     system_theme_data.dbus = dbus;
-    if (dbus == NULL) {
+    if (!dbus) {
         return SDL_FALSE;
     }
 
     msg = dbus->message_new_method_call(PORTAL_DESTINATION, PORTAL_PATH, PORTAL_INTERFACE, PORTAL_METHOD);
-    if (msg != NULL) {
+    if (msg) {
         if (dbus->message_append_args(msg, DBUS_TYPE_STRING, &namespace, DBUS_TYPE_STRING, &key, DBUS_TYPE_INVALID)) {
             DBusMessage *reply = dbus->connection_send_with_reply_and_block(dbus->session_conn, msg, 300, NULL);
             if (reply) {

src/core/linux/SDL_threadprio.c

@@ -111,19 +111,19 @@ static void rtkit_initialize(void)
     dbus_conn = get_rtkit_dbus_connection();
 
     /* Try getting minimum nice level: this is often greater than PRIO_MIN (-20). */
-    if (dbus_conn == NULL || !SDL_DBus_QueryPropertyOnConnection(dbus_conn, rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "MinNiceLevel",
+    if (!dbus_conn || !SDL_DBus_QueryPropertyOnConnection(dbus_conn, rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "MinNiceLevel",
                                                                  DBUS_TYPE_INT32, &rtkit_min_nice_level)) {
         rtkit_min_nice_level = -20;
     }
 
     /* Try getting maximum realtime priority: this can be less than the POSIX default (99). */
-    if (dbus_conn == NULL || !SDL_DBus_QueryPropertyOnConnection(dbus_conn, rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "MaxRealtimePriority",
+    if (!dbus_conn || !SDL_DBus_QueryPropertyOnConnection(dbus_conn, rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "MaxRealtimePriority",
                                                                  DBUS_TYPE_INT32, &rtkit_max_realtime_priority)) {
         rtkit_max_realtime_priority = 99;
     }
 
     /* Try getting maximum rttime allowed by rtkit: exceeding this value will result in SIGKILL */
-    if (dbus_conn == NULL || !SDL_DBus_QueryPropertyOnConnection(dbus_conn, rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "RTTimeUSecMax",
+    if (!dbus_conn || !SDL_DBus_QueryPropertyOnConnection(dbus_conn, rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "RTTimeUSecMax",
                                                                  DBUS_TYPE_INT64, &rtkit_max_rttime_usec)) {
         rtkit_max_rttime_usec = 200000;
     }
@@ -202,7 +202,7 @@ static SDL_bool rtkit_setpriority_nice(pid_t thread, int nice_level)
         nice = rtkit_min_nice_level;
     }
 
-    if (dbus_conn == NULL || !SDL_DBus_CallMethodOnConnection(dbus_conn,
+    if (!dbus_conn || !SDL_DBus_CallMethodOnConnection(dbus_conn,
                                                               rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "MakeThreadHighPriorityWithPID",
                                                               DBUS_TYPE_UINT64, &pid, DBUS_TYPE_UINT64, &tid, DBUS_TYPE_INT32, &nice, DBUS_TYPE_INVALID,
                                                               DBUS_TYPE_INVALID)) {
@@ -233,7 +233,7 @@ static SDL_bool rtkit_setpriority_realtime(pid_t thread, int rt_priority)
     // go through to determine whether it really needs to fail or not.
     rtkit_initialize_realtime_thread();
 
-    if (dbus_conn == NULL || !SDL_DBus_CallMethodOnConnection(dbus_conn,
+    if (!dbus_conn || !SDL_DBus_CallMethodOnConnection(dbus_conn,
                                                               rtkit_dbus_node, rtkit_dbus_path, rtkit_dbus_interface, "MakeThreadRealtimeWithPID",
                                                               DBUS_TYPE_UINT64, &pid, DBUS_TYPE_UINT64, &tid, DBUS_TYPE_UINT32, &priority, DBUS_TYPE_INVALID,
                                                               DBUS_TYPE_INVALID)) {

src/core/linux/SDL_udev.c

@@ -47,7 +47,7 @@ static void device_event(SDL_UDEV_deviceevent type, struct udev_device *dev);
 static SDL_bool SDL_UDEV_load_sym(const char *fn, void **addr)
 {
     *addr = SDL_LoadFunction(_this->udev_handle, fn);
-    if (*addr == NULL) {
+    if (!*addr) {
         /* Don't call SDL_SetError(): SDL_LoadFunction already did. */
         return SDL_FALSE;
     }
@@ -96,7 +96,7 @@ static int SDL_UDEV_load_syms(void)
 
 static SDL_bool SDL_UDEV_hotplug_update_available(void)
 {
-    if (_this->udev_mon != NULL) {
+    if (_this->udev_mon) {
         const int fd = _this->syms.udev_monitor_get_fd(_this->udev_mon);
         if (SDL_IOReady(fd, SDL_IOR_READ, 0)) {
             return SDL_TRUE;
@@ -109,9 +109,9 @@ int SDL_UDEV_Init(void)
 {
     int retval = 0;
 
-    if (_this == NULL) {
+    if (!_this) {
         _this = (SDL_UDEV_PrivateData *)SDL_calloc(1, sizeof(*_this));
-        if (_this == NULL) {
+        if (!_this) {
             return SDL_OutOfMemory();
         }
 
@@ -126,13 +126,13 @@ int SDL_UDEV_Init(void)
          */
 
         _this->udev = _this->syms.udev_new();
-        if (_this->udev == NULL) {
+        if (!_this->udev) {
             SDL_UDEV_Quit();
             return SDL_SetError("udev_new() failed");
         }
 
         _this->udev_mon = _this->syms.udev_monitor_new_from_netlink(_this->udev, "udev");
-        if (_this->udev_mon == NULL) {
+        if (!_this->udev_mon) {
             SDL_UDEV_Quit();
             return SDL_SetError("udev_monitor_new_from_netlink() failed");
         }
@@ -152,7 +152,7 @@ int SDL_UDEV_Init(void)
 
 void SDL_UDEV_Quit(void)
 {
-    if (_this == NULL) {
+    if (!_this) {
         return;
     }
 
@@ -160,17 +160,17 @@ void SDL_UDEV_Quit(void)
 
     if (_this->ref_count < 1) {
 
-        if (_this->udev_mon != NULL) {
+        if (_this->udev_mon) {
             _this->syms.udev_monitor_unref(_this->udev_mon);
             _this->udev_mon = NULL;
         }
-        if (_this->udev != NULL) {
+        if (_this->udev) {
             _this->syms.udev_unref(_this->udev);
             _this->udev = NULL;
         }
 
         /* Remove existing devices */
-        while (_this->first != NULL) {
+        while (_this->first) {
             SDL_UDEV_CallbackList *item = _this->first;
             _this->first = _this->first->next;
             SDL_free(item);
@@ -188,12 +188,12 @@ int SDL_UDEV_Scan(void)
     struct udev_list_entry *devs = NULL;
     struct udev_list_entry *item = NULL;
 
-    if (_this == NULL) {
+    if (!_this) {
         return 0;
     }
 
     enumerate = _this->syms.udev_enumerate_new(_this->udev);
-    if (enumerate == NULL) {
+    if (!enumerate) {
         SDL_UDEV_Quit();
         return SDL_SetError("udev_enumerate_new() failed");
     }
@@ -206,7 +206,7 @@ int SDL_UDEV_Scan(void)
     for (item = devs; item; item = _this->syms.udev_list_entry_get_next(item)) {
         const char *path = _this->syms.udev_list_entry_get_name(item);
         struct udev_device *dev = _this->syms.udev_device_new_from_syspath(_this->udev, path);
-        if (dev != NULL) {
+        if (dev) {
             device_event(SDL_UDEV_DEVICEADDED, dev);
             _this->syms.udev_device_unref(dev);
         }
@@ -223,12 +223,12 @@ SDL_bool SDL_UDEV_GetProductInfo(const char *device_path, Uint16 *vendor, Uint16
     struct udev_list_entry *item = NULL;
     SDL_bool found = SDL_FALSE;
 
-    if (_this == NULL) {
+    if (!_this) {
         return SDL_FALSE;
     }
 
     enumerate = _this->syms.udev_enumerate_new(_this->udev);
-    if (enumerate == NULL) {
+    if (!enumerate) {
         SDL_SetError("udev_enumerate_new() failed");
         return SDL_FALSE;
     }
@@ -238,7 +238,7 @@ SDL_bool SDL_UDEV_GetProductInfo(const char *device_path, Uint16 *vendor, Uint16
     for (item = devs; item && !found; item = _this->syms.udev_list_entry_get_next(item)) {
         const char *path = _this->syms.udev_list_entry_get_name(item);
         struct udev_device *dev = _this->syms.udev_device_new_from_syspath(_this->udev, path);
-        if (dev != NULL) {
+        if (dev) {
             const char *val = NULL;
             const char *existing_path;
 
@@ -247,17 +247,17 @@ SDL_bool SDL_UDEV_GetProductInfo(const char *device_path, Uint16 *vendor, Uint16
                 found = SDL_TRUE;
 
                 val = _this->syms.udev_device_get_property_value(dev, "ID_VENDOR_ID");
-                if (val != NULL) {
+                if (val) {
                     *vendor = (Uint16)SDL_strtol(val, NULL, 16);
                 }
 
                 val = _this->syms.udev_device_get_property_value(dev, "ID_MODEL_ID");
-                if (val != NULL) {
+                if (val) {
                     *product = (Uint16)SDL_strtol(val, NULL, 16);
                 }
 
                 val = _this->syms.udev_device_get_property_value(dev, "ID_REVISION");
-                if (val != NULL) {
+                if (val) {
                     *version = (Uint16)SDL_strtol(val, NULL, 16);
                 }
             }
@@ -271,11 +271,11 @@ SDL_bool SDL_UDEV_GetProductInfo(const char *device_path, Uint16 *vendor, Uint16
 
 void SDL_UDEV_UnloadLibrary(void)
 {
-    if (_this == NULL) {
+    if (!_this) {
         return;
     }
 
-    if (_this->udev_handle != NULL) {
+    if (_this->udev_handle) {
         SDL_UnloadObject(_this->udev_handle);
         _this->udev_handle = NULL;
     }
@@ -285,7 +285,7 @@ int SDL_UDEV_LoadLibrary(void)
 {
     int retval = 0, i;
 
-    if (_this == NULL) {
+    if (!_this) {
         return SDL_SetError("UDEV not initialized");
     }
 
@@ -296,9 +296,9 @@ int SDL_UDEV_LoadLibrary(void)
 
 #ifdef SDL_UDEV_DYNAMIC
     /* Check for the build environment's libudev first */
-    if (_this->udev_handle == NULL) {
+    if (!_this->udev_handle) {
         _this->udev_handle = SDL_LoadObject(SDL_UDEV_DYNAMIC);
-        if (_this->udev_handle != NULL) {
+        if (_this->udev_handle) {
             retval = SDL_UDEV_load_syms();
             if (retval < 0) {
                 SDL_UDEV_UnloadLibrary();
@@ -307,10 +307,10 @@ int SDL_UDEV_LoadLibrary(void)
     }
 #endif
 
-    if (_this->udev_handle == NULL) {
+    if (!_this->udev_handle) {
         for (i = 0; i < SDL_arraysize(SDL_UDEV_LIBS); i++) {
             _this->udev_handle = SDL_LoadObject(SDL_UDEV_LIBS[i]);
-            if (_this->udev_handle != NULL) {
+            if (_this->udev_handle) {
                 retval = SDL_UDEV_load_syms();
                 if (retval < 0) {
                     SDL_UDEV_UnloadLibrary();
@@ -320,7 +320,7 @@ int SDL_UDEV_LoadLibrary(void)
             }
         }
 
-        if (_this->udev_handle == NULL) {
+        if (!_this->udev_handle) {
             retval = -1;
             /* Don't call SDL_SetError(): SDL_LoadObject already did. */
         }
@@ -339,7 +339,7 @@ static void get_caps(struct udev_device *dev, struct udev_device *pdev, const ch
 
     SDL_memset(bitmask, 0, bitmask_len * sizeof(*bitmask));
     value = _this->syms.udev_device_get_sysattr_value(pdev, attr);
-    if (value == NULL) {
+    if (!value) {
         return;
     }
 
@@ -374,7 +374,7 @@ static int guess_device_class(struct udev_device *dev)
     while (pdev && !_this->syms.udev_device_get_sysattr_value(pdev, "capabilities/ev")) {
         pdev = _this->syms.udev_device_get_parent_with_subsystem_devtype(pdev, "input", NULL);
     }
-    if (pdev == NULL) {
+    if (!pdev) {
         return 0;
     }
 
@@ -400,7 +400,7 @@ static void device_event(SDL_UDEV_deviceevent type, struct udev_device *dev)
     SDL_UDEV_CallbackList *item;
 
     path = _this->syms.udev_device_get_devnode(dev);
-    if (path == NULL) {
+    if (!path) {
         return;
     }
 
@@ -411,23 +411,23 @@ static void device_event(SDL_UDEV_deviceevent type, struct udev_device *dev)
         /* udev rules reference: http://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-input_id.c */
 
         val = _this->syms.udev_device_get_property_value(dev, "ID_INPUT_JOYSTICK");
-        if (val != NULL && SDL_strcmp(val, "1") == 0) {
+        if (val && SDL_strcmp(val, "1") == 0) {
             devclass |= SDL_UDEV_DEVICE_JOYSTICK;
         }
 
         val = _this->syms.udev_device_get_property_value(dev, "ID_INPUT_ACCELEROMETER");
         if (SDL_GetHintBoolean(SDL_HINT_ACCELEROMETER_AS_JOYSTICK, SDL_TRUE) &&
-            val != NULL && SDL_strcmp(val, "1") == 0) {
+            val && SDL_strcmp(val, "1") == 0) {
             devclass |= SDL_UDEV_DEVICE_JOYSTICK;
         }
 
         val = _this->syms.udev_device_get_property_value(dev, "ID_INPUT_MOUSE");
-        if (val != NULL && SDL_strcmp(val, "1") == 0) {
+        if (val && SDL_strcmp(val, "1") == 0) {
             devclass |= SDL_UDEV_DEVICE_MOUSE;
         }
 
         val = _this->syms.udev_device_get_property_value(dev, "ID_INPUT_TOUCHSCREEN");
-        if (val != NULL && SDL_strcmp(val, "1") == 0) {
+        if (val && SDL_strcmp(val, "1") == 0) {
             devclass |= SDL_UDEV_DEVICE_TOUCHSCREEN;
         }
 
@@ -438,19 +438,19 @@ static void device_event(SDL_UDEV_deviceevent type, struct udev_device *dev)
            Ref: http://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-input_id.c#n183
         */
         val = _this->syms.udev_device_get_property_value(dev, "ID_INPUT_KEY");
-        if (val != NULL && SDL_strcmp(val, "1") == 0) {
+        if (val && SDL_strcmp(val, "1") == 0) {
             devclass |= SDL_UDEV_DEVICE_HAS_KEYS;
         }
 
         val = _this->syms.udev_device_get_property_value(dev, "ID_INPUT_KEYBOARD");
-        if (val != NULL && SDL_strcmp(val, "1") == 0) {
+        if (val && SDL_strcmp(val, "1") == 0) {
             devclass |= SDL_UDEV_DEVICE_KEYBOARD;
         }
 
         if (devclass == 0) {
             /* Fall back to old style input classes */
             val = _this->syms.udev_device_get_property_value(dev, "ID_CLASS");
-            if (val != NULL) {
+            if (val) {
                 if (SDL_strcmp(val, "joystick") == 0) {
                     devclass = SDL_UDEV_DEVICE_JOYSTICK;
                 } else if (SDL_strcmp(val, "mouse") == 0) {
@@ -470,7 +470,7 @@ static void device_event(SDL_UDEV_deviceevent type, struct udev_device *dev)
     }
 
     /* Process callbacks */
-    for (item = _this->first; item != NULL; item = item->next) {
+    for (item = _this->first; item; item = item->next) {
         item->callback(type, devclass, path);
     }
 }
@@ -480,13 +480,13 @@ void SDL_UDEV_Poll(void)
     struct udev_device *dev = NULL;
     const char *action = NULL;
 
-    if (_this == NULL) {
+    if (!_this) {
         return;
     }
 
     while (SDL_UDEV_hotplug_update_available()) {
         dev = _this->syms.udev_monitor_receive_device(_this->udev_mon);
-        if (dev == NULL) {
+        if (!dev) {
             break;
         }
         action = _this->syms.udev_device_get_action(dev);
@@ -507,13 +507,13 @@ int SDL_UDEV_AddCallback(SDL_UDEV_Callback cb)
 {
     SDL_UDEV_CallbackList *item;
     item = (SDL_UDEV_CallbackList *)SDL_calloc(1, sizeof(SDL_UDEV_CallbackList));
-    if (item == NULL) {
+    if (!item) {
         return SDL_OutOfMemory();
     }
 
     item->callback = cb;
 
-    if (_this->last == NULL) {
+    if (!_this->last) {
         _this->first = _this->last = item;
     } else {
         _this->last->next = item;
@@ -528,14 +528,14 @@ void SDL_UDEV_DelCallback(SDL_UDEV_Callback cb)
     SDL_UDEV_CallbackList *item;
     SDL_UDEV_CallbackList *prev = NULL;
 
-    if (_this == NULL) {
+    if (!_this) {
         return;
     }
 
-    for (item = _this->first; item != NULL; item = item->next) {
+    for (item = _this->first; item; item = item->next) {
         /* found it, remove it. */
         if (item->callback == cb) {
-            if (prev != NULL) {
+            if (prev) {
                 prev->next = item->next;
             } else {
                 SDL_assert(_this->first == item);