From 69dfeea15942d588fe0e4b18b51cf54cfde5b272 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Wed, 8 Sep 2010 20:52:13 +0000
Subject: [PATCH] skip junk in mp3_helix, refactor find_sync_word

git-svn-id: file:///home/notaz/opt/svn/PicoDrive/platform@889 be3aeb3a-fb24-0410-a615-afba39da0efa
---
 common/mp3.c       | 29 +++++++++++++++++++
 common/mp3.h       |  4 ++-
 common/mp3_helix.c | 70 ++++++++++++++++++++++------------------------
 gp2x/940ctl.c      |  3 +-
 gp2x/Makefile      |  2 +-
 linux/io.c         |  4 +--
 pandora/Makefile   |  2 +-
 pandora/plat.c     |  2 +-
 psp/mp3.c          |  8 +++---
 win32/plat.c       |  4 +--
 10 files changed, 78 insertions(+), 50 deletions(-)
 create mode 100644 common/mp3.c

diff --git a/common/mp3.c b/common/mp3.c
new file mode 100644
index 0000000..b00a5fb
--- /dev/null
+++ b/common/mp3.c
@@ -0,0 +1,29 @@
+#include "mp3.h"
+
+int mp3_find_sync_word(const unsigned char *buf, int size)
+{
+	const unsigned char *p, *pe;
+
+	/* find byte-aligned syncword - need 12 (MPEG 1,2) or 11 (MPEG 2.5) matching bits */
+	for (p = buf, pe = buf + size - 3; p <= pe; p++)
+	{
+		int pn;
+		if (p[0] != 0xff)
+			continue;
+		pn = p[1];
+		if ((pn & 0xf8) != 0xf8 || // currently must be MPEG1
+		    (pn & 6) == 0) {       // invalid layer
+			p++; continue;
+		}
+		pn = p[2];
+		if ((pn & 0xf0) < 0x20 || (pn & 0xf0) == 0xf0 || // bitrates
+		    (pn & 0x0c) != 0) { // not 44kHz
+			continue;
+		}
+
+		return p - buf;
+	}
+
+	return -1;
+}
+
diff --git a/common/mp3.h b/common/mp3.h
index 31b8d6f..da0987a 100644
--- a/common/mp3.h
+++ b/common/mp3.h
@@ -1,6 +1,8 @@
 
+int mp3_find_sync_word(const unsigned char *buf, int size);
+
 #ifdef __GP2X__
 void mp3_update_local(int *buffer, int length, int stereo);
-void mp3_start_play_local(FILE *f, int pos);
+void mp3_start_play_local(void *f, int pos);
 #endif
 
diff --git a/common/mp3_helix.c b/common/mp3_helix.c
index 4a4931f..75a4e75 100644
--- a/common/mp3_helix.c
+++ b/common/mp3_helix.c
@@ -23,39 +23,13 @@ static unsigned char mp3_input_buffer[2*1024];
 #define mp3_start_play mp3_start_play_local
 #endif
 
-static int find_sync_word(unsigned char *buf, int nBytes)
-{
-	unsigned char *p, *pe;
-
-	/* find byte-aligned syncword - need 12 (MPEG 1,2) or 11 (MPEG 2.5) matching bits */
-	for (p = buf, pe = buf + nBytes - 4; p < pe; p++)
-	{
-		int pn;
-		if (p[0] != 0xff) continue;
-		pn = p[1];
-		if ((pn & 0xf8) != 0xf8 || // currently must be MPEG1
-		    (pn & 6) == 0) {       // invalid layer
-			p++; continue;
-		}
-		pn = p[2];
-		if ((pn & 0xf0) < 0x20 || (pn & 0xf0) == 0xf0 || // bitrates
-		    (pn & 0x0c) != 0) { // not 44kHz
-			continue;
-		}
-
-		return p - buf;
-	}
-
-	return -1;
-}
-
 static int try_get_header(unsigned char *buff, MP3FrameInfo *fi)
 {
 	int ret, offs1, offs = 0;
 
 	while (1)
 	{
-		offs1 = find_sync_word(buff + offs, 2048 - offs);
+		offs1 = mp3_find_sync_word(buff + offs, 2048 - offs);
 		if (offs1 < 0) return -2;
 		offs += offs1;
 		if (2048 - offs < 4) return -3;
@@ -70,21 +44,24 @@ static int try_get_header(unsigned char *buff, MP3FrameInfo *fi)
 	return ret;
 }
 
-int mp3_get_bitrate(FILE *f, int len)
+int mp3_get_bitrate(void *f_, int len)
 {
 	unsigned char buff[2048];
 	MP3FrameInfo fi;
+	FILE *f = f_;
 	int ret;
 
-	memset(buff, 0, 2048);
+	memset(buff, 0, sizeof(buff));
 
-	if (mp3dec) MP3FreeDecoder(mp3dec);
+	if (mp3dec)
+		MP3FreeDecoder(mp3dec);
 	mp3dec = MP3InitDecoder();
 
 	fseek(f, 0, SEEK_SET);
-	ret = fread(buff, 1, 2048, f);
+	ret = fread(buff, 1, sizeof(buff), f);
 	fseek(f, 0, SEEK_SET);
-	if (ret <= 0) return -1;
+	if (ret <= 0)
+		return -1;
 
 	ret = try_get_header(buff, &fi);
 	if (ret != 0 || fi.bitrate == 0) {
@@ -94,7 +71,8 @@ int mp3_get_bitrate(FILE *f, int len)
 		fseek(f, 0, SEEK_SET);
 		ret = try_get_header(buff, &fi);
 	}
-	if (ret != 0) return ret;
+	if (ret != 0)
+		return ret;
 
 	// printf("bitrate: %i\n", fi.bitrate / 1000);
 
@@ -117,7 +95,7 @@ static int mp3_decode(void)
 		fseek(mp3_current_file, mp3_file_pos, SEEK_SET);
 		bytesLeft = fread(mp3_input_buffer, 1, sizeof(mp3_input_buffer), mp3_current_file);
 
-		offset = find_sync_word(mp3_input_buffer, bytesLeft);
+		offset = mp3_find_sync_word(mp3_input_buffer, bytesLeft);
 		if (offset < 0) {
 			lprintf("find_sync_word (%i/%i) err %i\n", mp3_file_pos, mp3_file_len, offset);
 			mp3_file_pos = mp3_file_len;
@@ -159,8 +137,10 @@ static int mp3_decode(void)
 	return 0;
 }
 
-void mp3_start_play(FILE *f, int pos)
+void mp3_start_play(void *f_, int pos)
 {
+	FILE *f = f_;
+
 	mp3_file_len = mp3_file_pos = 0;
 	mp3_current_file = NULL;
 	mp3_buffer_offs = 0;
@@ -177,11 +157,27 @@ void mp3_start_play(FILE *f, int pos)
 	fseek(f, 0, SEEK_END);
 	mp3_file_len = ftell(f);
 
+	// search for first sync word, skipping stuff like ID3 tags
+	while (mp3_file_pos < 128*1024) {
+		int offs, bytes;
+
+		fseek(f, mp3_file_pos, SEEK_SET);
+		bytes = fread(mp3_input_buffer, 1, sizeof(mp3_input_buffer), f);
+		if (bytes < 4)
+			break;
+		offs = mp3_find_sync_word(mp3_input_buffer, bytes);
+		if (offs >= 0) {
+			mp3_file_pos += offs;
+			break;
+		}
+		mp3_file_pos += bytes - 2;
+	}
+
 	// seek..
 	if (pos) {
-		unsigned long long pos64 = mp3_file_len;
+		unsigned long long pos64 = mp3_file_len - mp3_file_pos;
 		pos64 *= pos;
-		mp3_file_pos = pos64 >> 10;
+		mp3_file_pos += pos64 >> 10;
 	}
 
 	mp3_decode();
diff --git a/gp2x/940ctl.c b/gp2x/940ctl.c
index afd653f..76986a5 100644
--- a/gp2x/940ctl.c
+++ b/gp2x/940ctl.c
@@ -475,9 +475,10 @@ void mp3_update(int *buffer, int length, int stereo)
 }
 
 
-void mp3_start_play(FILE *f, int pos) // pos is 0-1023
+void mp3_start_play(void *f_, int pos) // pos is 0-1023
 {
 	int byte_offs = 0;
+	FILE *f = f_;
 
 	if (!(PicoOpt & POPT_EN_MCD_CDDA) || f == NULL)
 		return;
diff --git a/gp2x/Makefile b/gp2x/Makefile
index 431a357..2e5a104 100644
--- a/gp2x/Makefile
+++ b/gp2x/Makefile
@@ -57,7 +57,7 @@ OBJS += pico/sound/mix_arm.o
 # common
 OBJS += platform/common/emu.o platform/common/menu.o platform/common/fonts.o platform/common/config.o \
 	platform/common/arm_utils.o platform/common/arm_linux.o platform/common/readpng.o \
-	platform/common/mp3_helix.o platform/common/input.o platform/common/main.o \
+	platform/common/mp3_helix.o platform/common/input.o platform/common/main.o platform/common/mp3.o \
 	platform/linux/sndout_oss.o platform/linux/plat.o platform/linux/in_evdev.o
 
 # unzip
diff --git a/linux/io.c b/linux/io.c
index 7fff211..3fc5cc2 100644
--- a/linux/io.c
+++ b/linux/io.c
@@ -348,12 +348,12 @@ void plat_finish(void)
 }
 
 /* misc */
-int mp3_get_bitrate(FILE *f, int size)
+int mp3_get_bitrate(void *f, int size)
 {
 	return 128;
 }
 
-void mp3_start_play(FILE *f, int pos)
+void mp3_start_play(void *f, int pos)
 {
 }
 
diff --git a/pandora/Makefile b/pandora/Makefile
index 20d1b23..db3413b 100644
--- a/pandora/Makefile
+++ b/pandora/Makefile
@@ -48,7 +48,7 @@ OBJS += plat.o asm_utils.o
 # common
 OBJS += platform/common/emu.o platform/common/menu.o platform/common/fonts.o platform/common/config.o \
 	platform/common/arm_utils.o platform/common/mp3_helix.o platform/common/arm_linux.o \
-	platform/common/readpng.o platform/common/input.o platform/common/main.o \
+	platform/common/readpng.o platform/common/input.o platform/common/main.o platform/common/mp3.o \
 	platform/linux/fbdev.o platform/linux/in_evdev.o platform/linux/sndout_oss.o \
 	platform/linux/plat.o platform/linux/oshide.o
 
diff --git a/pandora/plat.c b/pandora/plat.c
index db0690c..e857bcc 100644
--- a/pandora/plat.c
+++ b/pandora/plat.c
@@ -155,7 +155,7 @@ void plat_video_wait_vsync(void)
 
 void plat_status_msg_clear(void)
 {
-	vout_fbdev_clear_lines(layer_fb, g_screen_height - 8, 8);
+	vout_fbdev_clear_lines(layer_fb, g_osd_y, 8);
 }
 
 void plat_status_msg_busy_next(const char *msg)
diff --git a/psp/mp3.c b/psp/mp3.c
index c1e6089..049b9a5 100644
--- a/psp/mp3.c
+++ b/psp/mp3.c
@@ -300,11 +300,11 @@ static int decode_thread(SceSize args, void *argp)
 
 
 // might be called before initialization
-int mp3_get_bitrate(FILE *f, int size)
+int mp3_get_bitrate(void *f, int size)
 {
 	int ret, retval = -1, sample_rate, bitrate;
 	// filenames are stored instead handles in PSP, due to stupid max open file limit
-	char *fname = (char *)f;
+	char *fname = f;
 
 	/* make sure thread is not busy.. */
 	if (thread_busy_sem >= 0)
@@ -351,9 +351,9 @@ end:
 
 static int mp3_job_started = 0, mp3_samples_ready = 0, mp3_buffer_offs = 0, mp3_play_bufsel = 0;
 
-void mp3_start_play(FILE *f, int pos)
+void mp3_start_play(void *f, int pos)
 {
-	char *fname = (char *)f;
+	char *fname = f;
 
 	if (!initialized) return;
 
diff --git a/win32/plat.c b/win32/plat.c
index 91ef0e0..15aff22 100644
--- a/win32/plat.c
+++ b/win32/plat.c
@@ -219,12 +219,12 @@ void plat_debug_cat(char *str)
 }
 
 // required by pico
-int mp3_get_bitrate(FILE *f, int size)
+int mp3_get_bitrate(void *f, int size)
 {
 	return 128;
 }
 
-void mp3_start_play(FILE *f, int pos)
+void mp3_start_play(void *f, int pos)
 {
 }
 
-- 
2.39.2