To: sdl@libsdl.org

From: Christian Walther <cwalther@gmx.ch>
Date: Wed, 28 Dec 2005 12:13:20 +0100
Subject: [SDL] Fix for opening documents on Mac OS X < 10.4

The current code in SDLMain.m that transforms documents opened from the
Finder into command-line arguments (introduced in revision 1.14,
2005-08-11) uses the methods -[NSString lengthOfBytesUsingEncoding:] and
-[NSString getCString:maxLength:encoding:], which are only available in
Mac OS X 10.4.

Compiling this code on 10.3 produces warnings, and running it (i.e.
starting an SDL application by opening a document) leads to weird
behavior which I didn't investigate in detail ("*** -[NSCFString
lengthOfBytesUsingEncoding:]: selector not recognized" is printed to the
console log, and the SDL window never opens).

The attached patch removes the offending calls and uses -[NSString
UTF8String] instead, which is available everywhere. Tested on 10.3.9,
and I see no reason why it shouldn't also work on 10.2 and 10.4.

Two further comments:

* The comment above the -[SDLMain application: openFile:] implementation
says "You need to have a CFBundleDocumentsType section in your
Info.plist to get this message, apparently." This is not the case in my
experience - it worked just fine with a hand-built bare-bones
application consisting only of Test.app/Contents/MacOS/test, without any
Info.plist (although you have to press the option and command keys for
such an application to accept a dragged file).

* I took the liberty of cleaning up another area of SDLMain.m: I changed
"CustomApplicationMain (argc, argv)" to "CustomApplicationMain (int
argc, char **argv)". This avoids the "type of `argv' defaults to `int'"
warnings, and I'm not sure if leaving out the types could cause problems
on platforms where an int and a char** aren't of the same size.

  -Christian

src/main/macosx/SDLMain.m

@@ -190,7 +190,7 @@ static void setupWindowMenu(void)
 }
 
 /* Replacement for NSApplicationMain */
-static void CustomApplicationMain (argc, argv)
+static void CustomApplicationMain (int argc, char **argv)
 {
     NSAutoreleasePool	*pool = [[NSAutoreleasePool alloc] init];
     SDLMain				*sdlMain;
@@ -251,8 +251,8 @@ static void CustomApplicationMain (argc, argv)
     if (gCalledAppMainline)  /* app has started, ignore this document. */
         return FALSE;
 
-    unsigned buflen = [filename lengthOfBytesUsingEncoding:NSUTF8StringEncoding] + 1;
-    char *arg = (char *) malloc(buflen);
+    const char *temparg = [filename UTF8String];
+    char *arg = (char *) malloc(strlen(temparg) + 1);
     if (arg == NULL)
         return FALSE;
 
@@ -264,15 +264,10 @@ static void CustomApplicationMain (argc, argv)
     }
     gArgv = newargv;
 
-    BOOL rc = [filename getCString:arg maxLength:buflen encoding:NSUTF8StringEncoding];
-    if (!rc)
-        free(arg);
-    else
-    {
-        gArgv[gArgc++] = arg;
-        gArgv[gArgc] = NULL;
-    }
-    return rc;
+    strcpy(arg, temparg);
+    gArgv[gArgc++] = arg;
+    gArgv[gArgc] = NULL;
+    return TRUE;
 }