engine: append log to the crash log on Android

android/app/src/main/java/su/xash/engine/MainActivity.kt

@@ -153,6 +153,7 @@ class MainActivity : AppCompatActivity() {
 		moveOrCopy(pending, File(entryDir, CrashReports.STACKTRACE_NAME))
 		moveOrCopy(CrashReports.pendingSysinfo(this), File(entryDir, CrashReports.SYSINFO_NAME))
 		moveOrCopy(CrashReports.pendingIntent(this), File(entryDir, CrashReports.INTENT_NAME))
+		moveOrCopy(CrashReports.pendingEngineLog(this), File(entryDir, CrashReports.ENGINELOG_NAME))
 
 		val entry = CrashReports.Entry(entryDir)
 		AlertDialog.Builder(this)
@@ -171,7 +172,7 @@ class MainActivity : AppCompatActivity() {
 		if (src.renameTo(dst))
 			return
 
-		dst.writeText(src.readText())
+		src.copyTo(dst, overwrite = true)
 		src.delete()
 	}
 

android/app/src/main/java/su/xash/engine/util/CrashReports.kt

@@ -24,6 +24,7 @@ object CrashReports {
 	const val STACKTRACE_NAME = "crash.log"
 	const val SYSINFO_NAME = "sysinfo.txt"
 	const val INTENT_NAME = "intent.txt"
+	const val ENGINELOG_NAME = "engine.log"
 
 	class Entry(val dir: File) {
 		val name: String get() = dir.name
@@ -31,8 +32,9 @@ object CrashReports {
 		val stacktrace: File get() = File(dir, STACKTRACE_NAME)
 		val sysinfo: File get() = File(dir, SYSINFO_NAME)
 		val intent: File get() = File(dir, INTENT_NAME)
+		val engineLog: File get() = File(dir, ENGINELOG_NAME)
 
-		fun attachments(): List<File> = listOf(stacktrace, sysinfo, intent).filter { it.exists() && it.length() > 0 }
+		fun attachments(): List<File> = listOf(stacktrace, sysinfo, intent, engineLog).filter { it.exists() && it.length() > 0 }
 
 		fun summary(): String = buildString {
 			if (stacktrace.exists())
@@ -52,6 +54,7 @@ object CrashReports {
 	fun pendingStacktrace(ctx: Context): File = File(pendingDir(ctx), STACKTRACE_NAME)
 	fun pendingSysinfo(ctx: Context): File = File(pendingDir(ctx), SYSINFO_NAME)
 	fun pendingIntent(ctx: Context): File = File(pendingDir(ctx), INTENT_NAME)
+	fun pendingEngineLog(ctx: Context): File = File(pendingDir(ctx), ENGINELOG_NAME)
 	fun historyDir(ctx: Context): File = File(ctx.filesDir, "crashes/history")
 
 	// wipe everything on app update; otherwise drop logs older than 30 days
@@ -65,6 +68,7 @@ object CrashReports {
 			pendingStacktrace(ctx).delete()
 			pendingSysinfo(ctx).delete()
 			pendingIntent(ctx).delete()
+			pendingEngineLog(ctx).delete()
 			prefs.edit().putInt(KEY_LAST_VERSION, currentVersion).apply()
 			return
 		}

engine/common/sys_con.c

@@ -95,8 +95,8 @@ void Sys_InitLog( void )
 
 	const char *mode;
 	if( host.change_game && host.type != HOST_DEDICATED )
-		mode = "a";
+		mode = "a+";
-	else mode = "w";
+	else mode = "w+";
 
 	if( Host_IsDedicated( ))
 		Q_strncpy( s_ld.title, XASH_DEDICATED_SERVER_NAME " " XASH_VERSION, sizeof( s_ld.title ));

engine/platform/posix/crash_posix.c

@@ -21,6 +21,7 @@ GNU General Public License for more details.
 #if XASH_ANDROID
 #include <sys/stat.h>
 #include <fcntl.h>
+#include <unistd.h>
 #include <android/log.h>
 #endif
 #include "library.h"
@@ -29,6 +30,7 @@ GNU General Public License for more details.
 
 #if XASH_ANDROID
 static char crashlog_path[MAX_OSPATH];
+static char enginelog_path[MAX_OSPATH];
 #endif
 
 static qboolean have_libbacktrace = false;
@@ -79,6 +81,26 @@ static void Sys_Crash( int signal, siginfo_t *si, void *context )
 		}
 	}
 
+	// make a copy of engine.log in staging directory
+	// TODO: dump log from console buffers, if -log not enabled
+	if( logfd >= 0 && enginelog_path[0] && lseek( logfd, 0, SEEK_SET ) == 0 )
+	{
+		int outfd = open( enginelog_path, O_WRONLY|O_CREAT|O_TRUNC, 0644 );
+		if( outfd >= 0 )
+		{
+			static char buf[8192];
+			while( 1 )
+			{
+				ssize_t n = read( logfd, buf, sizeof( buf ));
+				if( n <= 0 )
+					break;
+				if( write( outfd, buf, (size_t)n ) != n )
+					break;
+			}
+			close( outfd );
+		}
+	}
+
 	// JNI/SDL calls aren't safe from a signal handler on Android
 	_exit( 128 + signal );
 #else
@@ -115,7 +137,10 @@ void Sys_SetupCrashHandler( const char *argv0 )
 	const char *crashdir = getenv( "XASH3D_CRASH_DIR" );
 
 	if( !COM_StringEmptyOrNULL( crashdir ))
+	{
 		Q_snprintf( crashlog_path, sizeof( crashlog_path ), "%s/crash.log", crashdir );
+		Q_snprintf( enginelog_path, sizeof( enginelog_path ), "%s/engine.log", crashdir );
+	}
 
 	// unblock the engine/SDL_main thread just in case
 	sigset_t set;