main: Ensure SDL_RunApp() calls mainFunction() with a non-null argv

castholm · castholm · commit aa81cba65ea9 · 2025-03-29T21:20:25.000+01:00
If the specified argv is NULL, `SDL_RunApp()` will now use a dummy argv
instead, on all platforms.
diff --git a/VisualC-GDK/SDL/SDL.vcxproj b/VisualC-GDK/SDL/SDL.vcxproj
@@ -478,6 +478,7 @@
     <ClInclude Include="..\..\src\libm\math_private.h" />
     <ClInclude Include="..\..\src\locale\SDL_syslocale.h" />
     <ClInclude Include="..\..\src\main\SDL_main_callbacks.h" />
+    <ClInclude Include="..\..\src\main\SDL_runapp.h" />
     <ClInclude Include="..\..\src\misc\SDL_sysurl.h" />
     <ClInclude Include="..\..\src\power\SDL_syspower.h" />
     <ClInclude Include="..\..\src\render\direct3d11\SDL_shaders_d3d11.h" />
diff --git a/VisualC-GDK/SDL/SDL.vcxproj.filters b/VisualC-GDK/SDL/SDL.vcxproj.filters
@@ -370,6 +370,7 @@
     <ClInclude Include="..\..\src\libm\math_private.h" />
     <ClInclude Include="..\..\src\locale\SDL_syslocale.h" />
     <ClInclude Include="..\..\src\main\SDL_main_callbacks.h" />
+    <ClInclude Include="..\..\src\main\SDL_runapp.h" />
     <ClInclude Include="..\..\src\misc\SDL_sysurl.h" />
     <ClInclude Include="..\..\src\power\SDL_syspower.h" />
     <ClInclude Include="..\..\src\render\direct3d11\SDL_shaders_d3d11.h" />
diff --git a/VisualC/SDL/SDL.vcxproj b/VisualC/SDL/SDL.vcxproj
@@ -391,6 +391,7 @@
     <ClInclude Include="..\..\src\libm\math_private.h" />
     <ClInclude Include="..\..\src\locale\SDL_syslocale.h" />
     <ClInclude Include="..\..\src\main\SDL_main_callbacks.h" />
+    <ClInclude Include="..\..\src\main\SDL_runapp.h" />
     <ClInclude Include="..\..\src\misc\SDL_sysurl.h" />
     <ClInclude Include="..\..\src\power\SDL_syspower.h" />
     <ClInclude Include="..\..\src\render\direct3d11\SDL_shaders_d3d11.h" />
diff --git a/VisualC/SDL/SDL.vcxproj.filters b/VisualC/SDL/SDL.vcxproj.filters
@@ -459,6 +459,9 @@
     <ClInclude Include="..\..\src\main\SDL_main_callbacks.h">
       <Filter>main</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\main\SDL_runapp.h">
+      <Filter>main</Filter>
+    </ClInclude>
     <ClInclude Include="..\..\src\SDL_error_c.h" />
     <ClInclude Include="..\..\src\SDL_hashtable.h" />
     <ClInclude Include="..\..\src\SDL_list.h" />
diff --git a/src/main/SDL_runapp.c b/src/main/SDL_runapp.c
@@ -19,6 +19,7 @@
   3. This notice may not be removed or altered from any source distribution.
 */
 #include "SDL_internal.h"
+#include "SDL_runapp.h"
 
 /* Most platforms that use/need SDL_main have their own SDL_RunApp() implementation.
  * If not, you can special case it here by appending || defined(__YOUR_PLATFORM__) */
@@ -28,16 +29,20 @@ int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserv
 {
     (void)reserved;
 
-    if(!argv)
-    {
-        // make sure argv isn't NULL, in case some user code doesn't like that
-        static char dummyargv0[] = { 'S', 'D', 'L', '_', 'a', 'p', 'p', '\0' };
-        static char* argvdummy[2] = { dummyargv0, NULL };
+    return SDL_CallMain(argc, argv, mainFunction);
+}
+
+#endif
+
+int SDL_CallMain(int argc, char* argv[], SDL_main_func mainFunction)
+{
+    char dummyargv0[] = { 'S', 'D', 'L', '_', 'a', 'p', 'p', '\0' };
+    char *dummyargv[2] = { dummyargv0, NULL };
+
+    if (!argv || argc < 0) {
         argc = 1;
-        argv = argvdummy;
+        argv = dummyargv;
     }
 
     return mainFunction(argc, argv);
 }
-
-#endif
diff --git a/src/main/SDL_runapp.h b/src/main/SDL_runapp.h
@@ -0,0 +1,27 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef SDL_runapp_h_
+#define SDL_runapp_h_
+
+int SDL_CallMain(int argc, char* argv[], SDL_main_func mainFunction);
+
+#endif // SDL_runapp_h_
diff --git a/src/main/emscripten/SDL_sysmain_runapp.c b/src/main/emscripten/SDL_sysmain_runapp.c
@@ -24,6 +24,8 @@
 
 #include <emscripten/emscripten.h>
 
+#include "../SDL_runapp.h"
+
 EM_JS_DEPS(sdlrunapp, "$dynCall,$stringToNewUTF8");
 
 int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserved)
@@ -50,7 +52,7 @@ int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserv
         }
     }, SDL_setenv_unsafe);
 
-    return mainFunction(argc, argv);
+    return SDL_CallMain(argc, argv, mainFunction);
 }
 
 #endif
diff --git a/src/main/gdk/SDL_sysmain_runapp.cpp b/src/main/gdk/SDL_sysmain_runapp.cpp
@@ -21,6 +21,7 @@
 #include "SDL_internal.h"
 
 extern "C" {
+#include "../SDL_runapp.h"
 #include "../../core/gdk/SDL_gdk.h"
 #include "../../core/windows/SDL_windows.h"
 #include "../../events/SDL_events_c.h"
@@ -40,7 +41,7 @@ static BOOL OutOfMemory(void)
 /* Gets the arguments with GetCommandLine, converts them to argc and argv
    and calls SDL_main */
 extern "C"
-int SDL_RunApp(int, char**, SDL_main_func mainFunction, void *reserved)
+int SDL_RunApp(int, char**, SDL_main_func mainFunction, void *)
 {
     LPWSTR *argvw;
     char **argv;
@@ -111,7 +112,7 @@ int SDL_RunApp(int, char**, SDL_main_func mainFunction, void *reserved)
         }
 
         // Run the application main() code
-        result = mainFunction(argc, argv);
+        result = SDL_CallMain(argc, argv, mainFunction);
 
         GDK_UnregisterChangeNotifications();
 
diff --git a/src/main/n3ds/SDL_sysmain_runapp.c b/src/main/n3ds/SDL_sysmain_runapp.c
@@ -25,24 +25,24 @@
 
 #include <3ds.h>
 
+#include "../SDL_runapp.h"
+
 int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserved)
 {
     int result;
+    (void)reserved;
+
     // init
     osSetSpeedupEnable(true);
     romfsInit();
 
     SDL_SetMainReady();
-    result = mainFunction(argc, argv);
+    result = SDL_CallMain(argc, argv, mainFunction);
 
     // quit
     romfsExit();
 
     return result;
 }
 
-#ifdef __cplusplus
-} // extern "C"
-#endif
-
 #endif
diff --git a/src/main/ps2/SDL_sysmain_runapp.c b/src/main/ps2/SDL_sysmain_runapp.c
@@ -36,6 +36,8 @@
 #include <sbv_patches.h>
 #include <ps2_filesystem_driver.h>
 
+#include "../SDL_runapp.h"
+
 __attribute__((weak)) void reset_IOP(void)
 {
     SifInitRpc(0);
@@ -74,7 +76,7 @@ int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserv
 
     SDL_SetMainReady();
 
-    res = mainFunction(argc, argv);
+    res = SDL_CallMain(argc, argv, mainFunction);
 
     deinit_drivers();
 
diff --git a/src/main/psp/SDL_sysmain_runapp.c b/src/main/psp/SDL_sysmain_runapp.c
@@ -27,6 +27,8 @@
 
 #include <pspkernel.h>
 #include <pspthreadman.h>
+
+#include "../SDL_runapp.h"
 #include "../../events/SDL_events_c.h"
 
 /* If application's main() is redefined as SDL_main, and libSDL_main is
@@ -76,7 +78,7 @@ int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserv
 
     SDL_SetMainReady();
 
-    return mainFunction(argc, argv);
+    return SDL_CallMain(argc, argv, mainFunction);
 }
 
 #endif // SDL_PLATFORM_PSP
diff --git a/src/main/windows/SDL_sysmain_runapp.c b/src/main/windows/SDL_sysmain_runapp.c
@@ -22,6 +22,7 @@
 
 #ifdef SDL_PLATFORM_WIN32
 
+#include "../SDL_runapp.h"
 #include "../../core/windows/SDL_windows.h"
 
 /* Win32-specific SDL_RunApp(), which does most of the SDL_main work,
@@ -85,7 +86,7 @@ int MINGW32_FORCEALIGN SDL_RunApp(int _argc, char* _argv[], SDL_main_func mainFu
     SDL_SetMainReady();
 
     // Run the application main() code
-    result = mainFunction(argc, argv);
+    result = SDL_CallMain(argc, argv, mainFunction);
 
     // Free argv, to avoid memory leak
     for (i = 0; i < argc; ++i) {
diff --git a/src/video/uikit/SDL_uikitappdelegate.m b/src/video/uikit/SDL_uikitappdelegate.m
@@ -29,6 +29,7 @@
 #import "SDL_uikitwindow.h"
 
 #include "../../events/SDL_events_c.h"
+#include "../../main/SDL_runapp.h"
 
 #ifdef main
 #undef main
@@ -42,31 +43,39 @@
 int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserved)
 {
     int i;
+    (void)reserved;
 
     // store arguments
     /* Note that we need to be careful about how we allocate/free memory here.
      * If the application calls SDL_SetMemoryFunctions(), we can't rely on
      * SDL_free() to use the same allocator after SDL_main() returns.
      */
     forward_main = mainFunction;
-    forward_argc = argc;
-    forward_argv = (char **)malloc((argc + 1) * sizeof(char *)); // This should NOT be SDL_malloc()
-    for (i = 0; i < argc; i++) {
-        forward_argv[i] = malloc((strlen(argv[i]) + 1) * sizeof(char)); // This should NOT be SDL_malloc()
-        strcpy(forward_argv[i], argv[i]);
+    if (argv) {
+        forward_argc = argc;
+        forward_argv = (char **)malloc((argc + 1) * sizeof(char *)); // This should NOT be SDL_malloc()
+        for (i = 0; i < argc; i++) {
+            forward_argv[i] = malloc((strlen(argv[i]) + 1) * sizeof(char)); // This should NOT be SDL_malloc()
+            strcpy(forward_argv[i], argv[i]);
+        }
+        forward_argv[i] = NULL;
+    } else {
+        forward_argc = 0;
+        forward_argv = NULL;
     }
-    forward_argv[i] = NULL;
 
     // Give over control to run loop, SDLUIKitDelegate will handle most things from here
     @autoreleasepool {
         UIApplicationMain(argc, argv, nil, [SDLUIKitDelegate getAppDelegateClassName]);
     }
 
-    // free the memory we used to hold copies of argc and argv
-    for (i = 0; i < forward_argc; i++) {
-        free(forward_argv[i]); // This should NOT be SDL_free()
+    if (forward_argv) {
+        // free the memory we used to hold copies of argc and argv
+        for (i = 0; i < forward_argc; i++) {
+            free(forward_argv[i]); // This should NOT be SDL_free()
+        }
+        free(forward_argv); // This should NOT be SDL_free()
     }
-    free(forward_argv); // This should NOT be SDL_free()
 
     return exit_status;
 }
@@ -395,7 +404,7 @@ - (void)postFinishLaunch
 
     // run the user's application, passing argc and argv
     SDL_SetiOSEventPump(true);
-    exit_status = forward_main(forward_argc, forward_argv);
+    exit_status = SDL_CallMain(forward_argc, forward_argv, forward_main);
     SDL_SetiOSEventPump(false);
 
     if (launchWindow) {

Original file line number	Diff line number	Diff line change
`@@ -24,6 +24,8 @@`
`24`	`24`
`25`	`25`	`#include <emscripten/emscripten.h>`
`26`	`26`
	`27`	`+#include "../SDL_runapp.h"`
	`28`	`+`
`27`	`29`	`EM_JS_DEPS(sdlrunapp, "$dynCall,$stringToNewUTF8");`
`28`	`30`
`29`	`31`	`int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserved)`
`@@ -50,7 +52,7 @@ int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserv`
`50`	`52`	`}`
`51`	`53`	`}, SDL_setenv_unsafe);`
`52`	`54`
`53`		`- return mainFunction(argc, argv);`
	`55`	`+ return SDL_CallMain(argc, argv, mainFunction);`
`54`	`56`	`}`
`55`	`57`
`56`	`58`	`#endif`