Minor fixes to improve thread safety

Signed-off-by: Mahyar Koshkouei <deltabeard@users.noreply.github.com>

source/main.c

@@ -223,7 +223,10 @@ static int changeFile(const char* ep_file)
 	static Thread thread = NULL;
 	static char* file = NULL;
 
-	/* If music is playing, stop it */
+	/**
+	 * If music is playing, stop it. Only one playback thread should be playing
+	 * at any time.
+	 */
 	if(thread != NULL)
 	{
 		/* Tell the thread to stop playback before we join it */
@@ -246,7 +249,7 @@ static int changeFile(const char* ep_file)
 
 	svcGetThreadPriority(&prio, CUR_THREAD_HANDLE);
 	thread = threadCreate(playFile, file, 32 * 1024, prio - 1,
-			-2, true);
+			-2, false);
 
 	return 0;
 }

source/playback.c

@@ -9,8 +9,11 @@
 #include "playback.h"
 #include "wav.h"
 
-static bool stop = false;
+volatile bool stop = false;
 
+/**
+ * Should only be called from a new thread only.
+ */
 void playFile(void* fileIn)
 {
 	struct decoder_fn decoder;
@@ -44,6 +47,7 @@ void playFile(void* fileIn)
 			break;
 
 		default:
+			threadExit(0);
 			return;
 	}
 
@@ -95,23 +99,23 @@ void playFile(void* fileIn)
 
 	while(stop == false)
 	{
-		/* Number of bytes read from file.
-		 * Static only for the purposes of the printf debug at the bottom.
-		 */
-		static size_t read = 0;
-
 		gfxSwapBuffers();
 		gfxFlushBuffers();
 		gspWaitForVBlank();
 
 		svcSleepThread(100 * 1000);
 
+		/* When the last buffer has finished playing, break. */
+		if(lastbuf == true && waveBuf[0].status == NDSP_WBUF_DONE &&
+				waveBuf[1].status == NDSP_WBUF_DONE)
+			break;
+
 		if(ndspChnIsPaused(CHANNEL) == true || lastbuf == true)
 			continue;
 
 		if(waveBuf[0].status == NDSP_WBUF_DONE)
 		{
-			read = (*decoder.decode)(&buffer1[0]);
+			size_t read = (*decoder.decode)(&buffer1[0]);
 
 			if(read == 0)
 			{
@@ -126,7 +130,7 @@ void playFile(void* fileIn)
 
 		if(waveBuf[1].status == NDSP_WBUF_DONE)
 		{
-			read = (*decoder.decode)(&buffer2[0]);
+			size_t read = (*decoder.decode)(&buffer2[0]);
 
 			if(read == 0)
 			{