Added better period_time setup to the ALSA output code.

Added end-of-file checking to the libac3.

ac3dec/libac3/bitstream.c

@@ -41,10 +41,11 @@ uint_32 current_word;
 
 ssize_t (*bitstream_fill_buffer)(uint_8**,uint_8**);
 
-uint_8 bitstream_get_byte(void)
+int bitstream_get_byte(void)
 {
 	if(chunk_start == chunk_end)
-		bitstream_fill_buffer(&chunk_start,&chunk_end);
+		if (bitstream_fill_buffer(&chunk_start,&chunk_end) <= 0)
+			return EOF;
 
 	return (*chunk_start++);
 }
@@ -54,7 +55,7 @@ uint_8 *bitstream_get_buffer_start(void)
 	return buffer_start;
 }
 
-void
+int
 bitstream_buffer_frame(uint_32 frame_size)
 {
   uint_32 bytes_read;
@@ -67,7 +68,8 @@ bitstream_buffer_frame(uint_32 frame_size)
     if(chunk_start > chunk_end)
 			printf("argh!\n");
     if(chunk_start == chunk_end)
-      bitstream_fill_buffer(&chunk_start,&chunk_end);
+      if (bitstream_fill_buffer(&chunk_start,&chunk_end) <= 0)
+      	return EOF;
 
     num_bytes = chunk_end - chunk_start;
 
@@ -84,7 +86,8 @@ bitstream_buffer_frame(uint_32 frame_size)
   buffer_start = buffer;
   buffer_end   = buffer + frame_size;
 
-	bits_left = 0;
+  bits_left = 0;
+  return 0;
 }
 
 

ac3dec/libac3/bitstream.h

@@ -52,10 +52,10 @@ extern uint_32 current_word;
 
 void bitstream_init(ssize_t(*fill_function)(uint_8**,uint_8**));
 
-uint_8 bitstream_get_byte(void);
+int bitstream_get_byte(void);
 
 uint_8 *bitstream_get_buffer_start(void);
-void bitstream_buffer_frame(uint_32 frame_size);
+int bitstream_buffer_frame(uint_32 frame_size);
 
 uint_32 bitstream_get_bh(uint_32 num_bits);
 

ac3dec/libac3/decode.c

@@ -82,7 +82,8 @@ ac3_decode_frame(void)
 	uint_32 i;
 
 	//find a syncframe and parse
-	parse_syncinfo(&syncinfo);
+	if (parse_syncinfo(&syncinfo) < 0)
+		return NULL;
 	if(error_flag)
 		goto error;
 

ac3dec/libac3/parse.c

@@ -24,6 +24,7 @@
 
 #include <stdlib.h>
 #include <stdio.h>
+#include <errno.h>
 #include "ac3.h"
 #include "ac3_internal.h"
 
@@ -114,9 +115,10 @@ parse_syncinfo_data(syncinfo_t *syncinfo, uint_8 *data)
 }
 
 /* Parse a syncinfo structure, minus the sync word */
-void
+int
 parse_syncinfo(syncinfo_t *syncinfo)
 {
+	int byte, idx;
 	uint_8 data[3];
 	uint_16 sync_word = 0;
 	uint_32 time_out = 1<<16;
@@ -128,7 +130,10 @@ parse_syncinfo(syncinfo_t *syncinfo)
 	// 
 	while(time_out--)
 	{
-		sync_word = (sync_word << 8) + bitstream_get_byte();
+		byte = bitstream_get_byte();
+		if (byte < 0)
+			return -ENOENT;
+		sync_word = (sync_word << 8) + byte;
 
 		if(sync_word == 0x0b77)
 			break;
@@ -138,14 +143,18 @@ parse_syncinfo(syncinfo_t *syncinfo)
 	// We need to read in the entire syncinfo struct (0x0b77 + 24 bits)
 	// in order to determine how big the frame is
 	//
-	data[0] = bitstream_get_byte();
-	data[1] = bitstream_get_byte();
-	data[2] = bitstream_get_byte();
+	for (idx = 0; idx < 3; idx++) {
+		byte = bitstream_get_byte();
+		if (byte < 0)
+			return -ENOENT;
+		data[idx] = byte;
+	}
 
 	parse_syncinfo_data(syncinfo, data);
 
 	// Buffer the entire syncframe 
-	bitstream_buffer_frame(syncinfo->frame_size * 2 - 5);
+	if (bitstream_buffer_frame(syncinfo->frame_size * 2 - 5) < 0)
+		return -ENOENT;
 
 	// Check the crc over the entire frame 
 	crc_init();
@@ -159,11 +168,12 @@ parse_syncinfo(syncinfo_t *syncinfo)
 	{
 		error_flag = 1;
 		fprintf(stderr,"** CRC failed - skipping frame **\n");
-		return;
+		return 0;
 	}
 
 	if (!(ac3_config.flags & AC3_QUIET))
 		stats_print_syncinfo(syncinfo);
+	return 0;
 }
 
 /*

ac3dec/libac3/parse.h

@@ -22,7 +22,7 @@
  */
 
 void parse_syncinfo_data(syncinfo_t *syncinfo, uint_8 *data);
-void parse_syncinfo(syncinfo_t *syncinfo);
+int parse_syncinfo(syncinfo_t *syncinfo);
 void parse_audblk(bsi_t *bsi,audblk_t *audblk);
 void parse_bsi(bsi_t *bsi);
 void parse_auxdata(syncinfo_t *syncinfo);