winmain: Don't use SDL_malloc (or SDL_stack_alloc, which might be mal…

…loc). Otherwise, we are using the allocator before the app can set up its own hooks. Now we use VirtualAlloc, and WideCharToMultiByte (because SDL_iconv uses SDL_malloc, too!) to get ready to call into SDL_main. This also makes console_wmain() call into the same routines as everything else, so we don't have to deal with those allocations, too. Hopefully we end up with the same results from GetCommandLine() as we do in wargv. Fixes Bugzilla #4340.
libsdl-org · Oct 30, 2018 · f434a98 · f434a98
1 parent b43f427
commit f434a98
Showing 1 changed file with 41 additions and 40 deletions.
diff --git a/src/main/windows/SDL_windows_main.c b/src/main/windows/SDL_windows_main.c
@@ -116,50 +116,65 @@ OutOfMemory(void)
 # endif
 #endif
 
-/* WinMain, main, and wmain eventually call into here. */
-static int
-main_utf8(int argc, char *argv[])
-{
-    SDL_SetMainReady();
-
-    /* Run the application main() code */
-    return SDL_main(argc, argv);
-}
-
 /* Gets the arguments with GetCommandLine, converts them to argc and argv
-   and calls main_utf8 */
+   and calls SDL_main */
 static int
 main_getcmdline()
 {
     char **argv;
     int argc;
-    char *cmdline;
+    char *cmdline = NULL;
     int retval = 0;
+    int cmdalloc = 0;
+    const TCHAR *text = GetCommandLine();
+    const TCHAR *ptr;
+    int argc_guess = 2;  /* space for NULL and initial argument. */
+    int rc;
+
+    /* make a rough guess of command line arguments. Overestimates if there
+       are quoted things. */
+    for (ptr = text; *ptr; ptr++) {
+        if ((*ptr == ' ') || (*ptr == '\t')) {
+            argc_guess++;
+        }
+    }
 
-    /* Grab the command line */
-    TCHAR *text = GetCommandLine();
 #if UNICODE
-    cmdline = WIN_StringToUTF8(text);
+    rc = WideCharToMultiByte(CP_UTF8, 0, text, -1, NULL, 0, NULL, NULL);
+    if (rc > 0) {
+        cmdalloc = rc + (sizeof (char *) * argc_guess);
+        argv = (char **) VirtualAlloc(NULL, cmdalloc, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
+        if (argv) {
+            cmdline = (char *) (argv + argc_guess);
+            const int rc2 = WideCharToMultiByte(CP_UTF8, 0, text, -1, cmdline, rc, NULL, NULL);
+            SDL_assert(rc2 == rc);
+        }
+    }
 #else
     /* !!! FIXME: are these in the system codepage? We need to convert to UTF-8. */
-    cmdline = SDL_strdup(text);
+    rc = ((int) SDL_strlen(text)) + 1;
+    cmdalloc = rc + (sizeof (char *) * argc_guess);
+    argv = (char **) VirtualAlloc(NULL, cmdalloc, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
+    if (argv) {
+        cmdline = (char *) (argv + argc_guess);
+        SDL_strcpy(cmdline, text);
+    }
 #endif
     if (cmdline == NULL) {
         return OutOfMemory();
     }
 
     /* Parse it into argv and argc */
-    argc = ParseCommandLine(cmdline, NULL);
-    argv = SDL_stack_alloc(char *, argc + 1);
-    if (argv == NULL) {
-        return OutOfMemory();
-    }
-    ParseCommandLine(cmdline, argv);
+    SDL_assert(ParseCommandLine(cmdline, NULL) <= argc_guess);
+    argc = ParseCommandLine(cmdline, argv);
 
-    retval = main_utf8(argc, argv);
+    SDL_SetMainReady();
 
-    SDL_stack_free(argv);
-    SDL_free(cmdline);
+    /* Run the application main() code */
+    retval = SDL_main(argc, argv);
+
+    VirtualFree(argv, cmdalloc, MEM_DECOMMIT);
+    VirtualFree(argv, 0, MEM_RELEASE);
 
     return retval;
 }
@@ -177,21 +192,7 @@ console_ansi_main(int argc, char *argv[])
 int
 console_wmain(int argc, wchar_t *wargv[], wchar_t *wenvp)
 {
-    int retval = 0;
-    char **argv = SDL_stack_alloc(char*, argc + 1);
-    int i;
-
-    for (i = 0; i < argc; ++i) {
-        argv[i] = WIN_StringToUTF8(wargv[i]);
-    }
-    argv[argc] = NULL;
-
-    retval = main_utf8(argc, argv);
-
-    /* !!! FIXME: we are leaking all the elements of argv we allocated. */
-    SDL_stack_free(argv);
-
-    return retval;
+    return main_getcmdline();
 }
 #endif