Use SDL_bool instead an int return code in the SDL API

Most SDL functions used to indicate success or failure using an int return code. These functions have been changed to return SDL_bool.

Here is a coccinelle patch to change code that previously compared the return value to 0 and changes it to a boolean test:
@ bool_return_type  @
identifier func =~ "^(SDL_AddEventWatch|SDL_AddHintCallback|SDL_AddSurfaceAlternateImage|SDL_AddVulkanRenderSemaphores|SDL_BindAudioStream|SDL_BindAudioStreams|SDL_BlitSurface|SDL_BlitSurface9Grid|SDL_BlitSurfaceScaled|SDL_BlitSurfaceTiled|SDL_BlitSurfaceTiledWithScale|SDL_BlitSurfaceUnchecked|SDL_BlitSurfaceUncheckedScaled|SDL_CaptureMouse|SDL_ClearAudioStream|SDL_ClearClipboardData|SDL_ClearComposition|SDL_ClearError|SDL_ClearProperty|SDL_ClearSurface|SDL_CloseIO|SDL_CloseStorage|SDL_ConvertAudioSamples|SDL_ConvertEventToRenderCoordinates|SDL_ConvertPixels|SDL_ConvertPixelsAndColorspace|SDL_CopyFile|SDL_CopyProperties|SDL_CopyStorageFile|SDL_CreateDirectory|SDL_CreateStorageDirectory|SDL_CreateWindowAndRenderer|SDL_DateTimeToTime|SDL_DestroyWindowSurface|SDL_DetachVirtualJoystick|SDL_DisableScreenSaver|SDL_EnableScreenSaver|SDL_EnumerateDirectory|SDL_EnumerateProperties|SDL_EnumerateStorageDirectory|SDL_FillSurfaceRect|SDL_FillSurfaceRects|SDL_FlashWindow|SDL_FlipSurface|SDL_FlushAudioStream|SDL_FlushRenderer|SDL_GL_DestroyContext|SDL_GL_GetAttribute|SDL_GL_GetSwapInterval|SDL_GL_LoadLibrary|SDL_GL_MakeCurrent|SDL_GL_SetAttribute|SDL_GL_SetSwapInterval|SDL_GL_SwapWindow|SDL_GetAudioDeviceFormat|SDL_GetAudioStreamFormat|SDL_GetCameraFormat|SDL_GetClosestFullscreenDisplayMode|SDL_GetCurrentRenderOutputSize|SDL_GetCurrentTime|SDL_GetDXGIOutputInfo|SDL_GetDateTimeLocalePreferences|SDL_GetDisplayBounds|SDL_GetDisplayUsableBounds|SDL_GetGDKDefaultUser|SDL_GetGDKTaskQueue|SDL_GetGamepadSensorData|SDL_GetGamepadTouchpadFinger|SDL_GetHapticEffectStatus|SDL_GetJoystickBall|SDL_GetMasksForPixelFormat|SDL_GetPathInfo|SDL_GetRectUnion|SDL_GetRectUnionFloat|SDL_GetRenderClipRect|SDL_GetRenderColorScale|SDL_GetRenderDrawBlendMode|SDL_GetRenderDrawColor|SDL_GetRenderDrawColorFloat|SDL_GetRenderLogicalPresentation|SDL_GetRenderLogicalPresentationRect|SDL_GetRenderOutputSize|SDL_GetRenderSafeArea|SDL_GetRenderScale|SDL_GetRenderVSync|SDL_GetRenderViewport|SDL_GetSensorData|SDL_GetStorageFileSize|SDL_GetStoragePathInfo|SDL_GetSurfaceAlphaMod|SDL_GetSurfaceBlendMode|SDL_GetSurfaceClipRect|SDL_GetSurfaceColorKey|SDL_GetSurfaceColorMod|SDL_GetTextInputArea|SDL_GetTextureAlphaMod|SDL_GetTextureAlphaModFloat|SDL_GetTextureBlendMode|SDL_GetTextureColorMod|SDL_GetTextureColorModFloat|SDL_GetTextureScaleMode|SDL_GetTextureSize|SDL_GetWindowAspectRatio|SDL_GetWindowBordersSize|SDL_GetWindowMaximumSize|SDL_GetWindowMinimumSize|SDL_GetWindowPosition|SDL_GetWindowRelativeMouseMode|SDL_GetWindowSafeArea|SDL_GetWindowSize|SDL_GetWindowSizeInPixels|SDL_GetWindowSurfaceVSync|SDL_HideCursor|SDL_HideWindow|SDL_Init|SDL_InitHapticRumble|SDL_InitSubSystem|SDL_LoadWAV|SDL_LoadWAV_IO|SDL_LockAudioStream|SDL_LockProperties|SDL_LockSurface|SDL_LockTexture|SDL_LockTextureToSurface|SDL_MaximizeWindow|SDL_MinimizeWindow|SDL_MixAudio|SDL_OpenURL|SDL_OutOfMemory|SDL_PauseAudioDevice|SDL_PauseAudioStreamDevice|SDL_PauseHaptic|SDL_PlayHapticRumble|SDL_PremultiplyAlpha|SDL_PremultiplySurfaceAlpha|SDL_PushEvent|SDL_PutAudioStreamData|SDL_RaiseWindow|SDL_ReadStorageFile|SDL_ReadSurfacePixel|SDL_ReadSurfacePixelFloat|SDL_RegisterApp|SDL_ReloadGamepadMappings|SDL_RemovePath|SDL_RemoveStoragePath|SDL_RemoveTimer|SDL_RenamePath|SDL_RenameStoragePath|SDL_RenderClear|SDL_RenderCoordinatesFromWindow|SDL_RenderCoordinatesToWindow|SDL_RenderFillRect|SDL_RenderFillRects|SDL_RenderGeometry|SDL_RenderGeometryRaw|SDL_RenderLine|SDL_RenderLines|SDL_RenderPoint|SDL_RenderPoints|SDL_RenderPresent|SDL_RenderRect|SDL_RenderRects|SDL_RenderTexture|SDL_RenderTexture9Grid|SDL_RenderTextureRotated|SDL_RenderTextureTiled|SDL_RequestAndroidPermission|SDL_RestoreWindow|SDL_ResumeAudioDevice|SDL_ResumeAudioStreamDevice|SDL_ResumeHaptic|SDL_RumbleGamepad|SDL_RumbleGamepadTriggers|SDL_RumbleJoystick|SDL_RumbleJoystickTriggers|SDL_RunHapticEffect|SDL_SaveBMP|SDL_SaveBMP_IO|SDL_SendAndroidMessage|SDL_SendGamepadEffect|SDL_SendJoystickEffect|SDL_SendJoystickVirtualSensorData|SDL_SetAppMetadata|SDL_SetAppMetadataProperty|SDL_SetAudioDeviceGain|SDL_SetAudioPostmixCallback|SDL_SetAudioStreamFormat|SDL_SetAudioStreamFrequencyRatio|SDL_SetAudioStreamGain|SDL_SetAudioStreamGetCallback|SDL_SetAudioStreamInputChannelMap|SDL_SetAudioStreamOutputChannelMap|SDL_SetAudioStreamPutCallback|SDL_SetBooleanProperty|SDL_SetClipboardData|SDL_SetClipboardText|SDL_SetCursor|SDL_SetFloatProperty|SDL_SetGamepadLED|SDL_SetGamepadMapping|SDL_SetGamepadPlayerIndex|SDL_SetGamepadSensorEnabled|SDL_SetHapticAutocenter|SDL_SetHapticGain|SDL_SetJoystickLED|SDL_SetJoystickPlayerIndex|SDL_SetJoystickVirtualAxis|SDL_SetJoystickVirtualBall|SDL_SetJoystickVirtualButton|SDL_SetJoystickVirtualHat|SDL_SetJoystickVirtualTouchpad|SDL_SetLinuxThreadPriority|SDL_SetLinuxThreadPriorityAndPolicy|SDL_SetLogPriorityPrefix|SDL_SetMemoryFunctions|SDL_SetNumberProperty|SDL_SetPaletteColors|SDL_SetPointerProperty|SDL_SetPointerPropertyWithCleanup|SDL_SetPrimarySelectionText|SDL_SetRenderClipRect|SDL_SetRenderColorScale|SDL_SetRenderDrawBlendMode|SDL_SetRenderDrawColor|SDL_SetRenderDrawColorFloat|SDL_SetRenderLogicalPresentation|SDL_SetRenderScale|SDL_SetRenderTarget|SDL_SetRenderVSync|SDL_SetRenderViewport|SDL_SetScancodeName|SDL_SetStringProperty|SDL_SetSurfaceAlphaMod|SDL_SetSurfaceBlendMode|SDL_SetSurfaceColorKey|SDL_SetSurfaceColorMod|SDL_SetSurfaceColorspace|SDL_SetSurfacePalette|SDL_SetSurfaceRLE|SDL_SetTLS|SDL_SetTextInputArea|SDL_SetTextureAlphaMod|SDL_SetTextureAlphaModFloat|SDL_SetTextureBlendMode|SDL_SetTextureColorMod|SDL_SetTextureColorModFloat|SDL_SetTextureScaleMode|SDL_SetThreadPriority|SDL_SetWindowAlwaysOnTop|SDL_SetWindowAspectRatio|SDL_SetWindowBordered|SDL_SetWindowFocusable|SDL_SetWindowFullscreen|SDL_SetWindowFullscreenMode|SDL_SetWindowHitTest|SDL_SetWindowIcon|SDL_SetWindowKeyboardGrab|SDL_SetWindowMaximumSize|SDL_SetWindowMinimumSize|SDL_SetWindowModalFor|SDL_SetWindowMouseGrab|SDL_SetWindowMouseRect|SDL_SetWindowOpacity|SDL_SetWindowPosition|SDL_SetWindowRelativeMouseMode|SDL_SetWindowResizable|SDL_SetWindowShape|SDL_SetWindowSize|SDL_SetWindowSurfaceVSync|SDL_SetWindowTitle|SDL_SetiOSAnimationCallback|SDL_ShowAndroidToast|SDL_ShowCursor|SDL_ShowMessageBox|SDL_ShowSimpleMessageBox|SDL_ShowWindow|SDL_ShowWindowSystemMenu|SDL_StartTextInput|SDL_StartTextInputWithProperties|SDL_StopHapticEffect|SDL_StopHapticEffects|SDL_StopHapticRumble|SDL_StopTextInput|SDL_SyncWindow|SDL_TimeToDateTime|SDL_TryLockMutex|SDL_TryLockRWLockForReading|SDL_TryLockRWLockForWriting|SDL_TryWaitSemaphore|SDL_UnlockAudioStream|SDL_UpdateHapticEffect|SDL_UpdateNVTexture|SDL_UpdateTexture|SDL_UpdateWindowSurface|SDL_UpdateWindowSurfaceRects|SDL_UpdateYUVTexture|SDL_Vulkan_CreateSurface|SDL_Vulkan_LoadLibrary|SDL_WaitConditionTimeout|SDL_WaitSemaphoreTimeout|SDL_WarpMouseGlobal|SDL_WriteStorageFile|SDL_WriteSurfacePixel|SDL_WriteSurfacePixelFloat)$";
@@
(
  func(
  ...
  )
- == 0
|
- func(
+ !func(
  ...
  )
- < 0
|
- func(
+ !func(
  ...
  )
- != 0
|
- func(
+ !func(
  ...
  )
- == -1
)

src/core/linux/SDL_threadprio.c

@@ -249,13 +249,13 @@ static bool rtkit_setpriority_realtime(pid_t thread, int rt_priority)
 #endif // threads
 
 // this is a public symbol, so it has to exist even if threads are disabled.
-int SDL_SetLinuxThreadPriority(Sint64 threadID, int priority)
+SDL_bool SDL_SetLinuxThreadPriority(Sint64 threadID, int priority)
 {
 #ifdef SDL_THREADS_DISABLED
     return SDL_Unsupported();
 #else
     if (setpriority(PRIO_PROCESS, (id_t)threadID, priority) == 0) {
-        return 0;
+        return true;
     }
 
 #ifdef SDL_USE_LIBDBUS
@@ -272,7 +272,7 @@ int SDL_SetLinuxThreadPriority(Sint64 threadID, int priority)
        README and sample code at: http://git.0pointer.net/rtkit.git
     */
     if (rtkit_setpriority_nice((pid_t)threadID, priority)) {
-        return 0;
+        return true;
     }
 #endif
 
@@ -281,7 +281,7 @@ int SDL_SetLinuxThreadPriority(Sint64 threadID, int priority)
 }
 
 // this is a public symbol, so it has to exist even if threads are disabled.
-int SDL_SetLinuxThreadPriorityAndPolicy(Sint64 threadID, int sdlPriority, int schedPolicy)
+SDL_bool SDL_SetLinuxThreadPriorityAndPolicy(Sint64 threadID, int sdlPriority, int schedPolicy)
 {
 #ifdef SDL_THREADS_DISABLED
     return SDL_Unsupported();
@@ -310,7 +310,7 @@ int SDL_SetLinuxThreadPriorityAndPolicy(Sint64 threadID, int sdlPriority, int sc
         }
 
         if (setpriority(PRIO_PROCESS, (id_t)threadID, osPriority) == 0) {
-            return 0;
+            return true;
         }
     }
 
@@ -329,11 +329,11 @@ int SDL_SetLinuxThreadPriorityAndPolicy(Sint64 threadID, int sdlPriority, int sc
     */
     if (schedPolicy == SCHED_RR || schedPolicy == SCHED_FIFO) {
         if (rtkit_setpriority_realtime((pid_t)threadID, osPriority)) {
-            return 0;
+            return true;
         }
     } else {
         if (rtkit_setpriority_nice((pid_t)threadID, osPriority)) {
-            return 0;
+            return true;
         }
     }
 #endif