Override fprintf(stderr) in android_debug.h

project/java/MainActivity.java

@@ -1327,7 +1327,7 @@ public class MainActivity extends Activity
 	public CloudSave cloudSave = null;
 	public ProgressDialog loadingDialog = null;
 
-	private FrameLayout _videoLayout = null;
+	FrameLayout _videoLayout = null;
 	private EditText _screenKeyboard = null;
 	private String _screenKeyboardHintMessage = null;
 	static boolean keyboardWithoutTextInputShown = false;

project/jni/application/android_debug.h

@@ -1,7 +1,11 @@
 #ifndef __ANDROID_DEBUG_H__
 #define __ANDROID_DEBUG_H__
 
+// Redirect printf() to Android log
+// Put this file into CFLAGS: "-include ../android_debug.h"
+
 #include <stdio.h>
+#include <stdarg.h>
 #include <android/log.h>
 
 #ifdef __cplusplus
@@ -46,4 +50,20 @@ namespace std
 
 #define printf(...) __android_log_print(ANDROID_LOG_INFO, "SDL-app", __VA_ARGS__)
 
+// Override fprintf(stderr, ...) constructs
+static inline int __sdl_logged_fprintf(FILE *stream, const char *format, ...)
+{
+	int ret = 0;
+	va_list args;
+	va_start(args, format);
+	if( stream == stderr || stream == stdout )
+		ret = __android_log_vprint(ANDROID_LOG_INFO, "SDL-app", format, args);
+	else
+		ret = vfprintf(stream, format, args);
+	va_end(args);
+	return ret;
+}
+
+#define fprintf(...) __sdl_logged_fprintf(__VA_ARGS__)
+
 #endif

readme.txt

@@ -350,7 +350,7 @@ Quick guide to debug native code
 ================================
 
 You need compile your app with debug enabled to be able to debug native code:
-./build.sh debug
+	./build.sh debug
 To debug your application - launch it, go to "project" dir and launch command
 	ndk-gdb
 then you can run usual GDB commands, like:
@@ -364,6 +364,10 @@ You can also debug by adding extensive logs to your app:
 	__android_log_print(ANDROID_LOG_INFO, "My App", "We somehow reached execution point #224");
 and then watching "adb logcat" output.
 
+Android does not print app stdout/stderr streams to logcat, so printf() will not work,
+but you can redefine printf() and fprintf(stderr) in your app to write to Android log by adding this to AppCflags:
+	-include jni/application/android_debug.h
+
 If your application crashed, you should use following steps:
 
 1. Gather the crash report from "adb logcat" - it should contain stack trace, if it does not then you're unlucky,