(iOS) If the token HAVE_DEBUG_DIAGLOG is defined at build time all messages sent to stdout or stderr will appear in the Diagnostic Log.

ios/RetroArch/RALogView.m

@@ -20,6 +20,7 @@
 static NSMutableArray* g_messages;
 static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER;
 
+#ifndef HAVE_DEBUG_DIAGLOG
 void ios_add_log_message(const char* format, ...)
 {
    pthread_mutex_lock(&g_lock);
@@ -36,6 +37,54 @@ void ios_add_log_message(const char* format, ...)
    
    pthread_mutex_unlock(&g_lock);
 }
+#else
+static FILE* old_stdout;
+static FILE* old_stderr;
+static FILE* log_stream;
+
+static int stdout_write(void* mem_buffer, const char* data, int len)
+{
+   pthread_mutex_lock(&g_lock);
+   
+   g_messages = g_messages ? g_messages : [NSMutableArray array];
+
+   char buffer[len + 10];
+   strncpy(buffer, data, len);
+   buffer[len] = 0;
+   
+   [g_messages addObject:[NSString stringWithFormat:@"%s", buffer]];
+   
+   pthread_mutex_unlock(&g_lock);
+   
+   return len;
+}
+
+void ios_log_init()
+{
+   if (!log_stream)
+   {
+      old_stdout = stdout;
+      old_stderr = stderr;
+
+      log_stream = fwopen(0, stdout_write);
+      setvbuf(log_stream, 0, _IOLBF, 0);
+      
+      stdout = log_stream;
+      stderr = log_stream;
+   }
+}
+
+void ios_log_quit()
+{
+   if (log_stream)
+   {
+      stdout = old_stdout;
+      stderr = old_stderr;
+      fclose(log_stream);
+      log_stream = 0;
+   }
+}
+#endif
 
 @implementation RALogView
 

ios/RetroArch/main.m

@@ -231,6 +231,10 @@ static void event_reload_config(void* userdata)
 // UIApplicationDelegate
 - (void)applicationDidFinishLaunching:(UIApplication *)application
 {
+#ifdef HAVE_DEBUG_DIAGLOG
+   ios_log_init();
+#endif
+
    self.system_directory = [NSString stringWithFormat:@"%@/.RetroArch", kDOCSFOLDER];
    self.systemConfigPath = [NSString stringWithFormat:@"%@/.RetroArch/frontend.cfg", kDOCSFOLDER];
    mkdir([self.system_directory UTF8String], 0755);

ios/RetroArch/rarch_wrapper.h

@@ -30,6 +30,13 @@ void ios_set_game_view_sync(unsigned interval);
 void ios_get_game_view_size(unsigned *width, unsigned *height);
 void ios_bind_game_view_fbo();
 
-// Thread safe
+#ifndef HAVE_DEBUG_DIAGLOG
 void ios_add_log_message(const char* format, ...);
+#else
+void ios_log_init();
+void ios_log_quit();
+// Thread safe
+#define ios_add_log_message(...) do { printf(__VA_ARGS__); printf("\n"); } while(0)
+#endif
+
 #endif