Changeset 423

Timestamp:

02/11/09 23:41:58 (16 years ago)

Author:

r2d

Message:

improves chapter parsing resilience to errors

File:

• libmpc/trunk/libmpcdec/mpc_demux.c (modified) (6 diffs)

libmpc/trunk/libmpcdec/mpc_demux.c

@@ -115 +115 @@
 
 /**
+ * checks if a block key is valid
+ * @param key the two caracters key to check
+ * @return MPC_STATUS_INVALIDSV if the key is invalid, MPC_STATUS_OK else
+ */
+static inline mpc_status mpc_check_key(char * key)
+{
+        if (key[0] < 65 || key[0] > 90 || key[1] < 65 || key[1] > 90)
+                return MPC_STATUS_INVALIDSV;
+        return MPC_STATUS_OK;
+}
+
+/**
  * seek to a bit position in the stream
  * @param d demuxer context
@@ -304 +316 @@
         int tag_size = 0, chap_size = 0, size, i = 0;
 
+        d->chap_nb = 0;
+
         if (d->si.stream_version < 8)
                 return;
@@ -312 +326 @@
                 size = mpc_bits_get_block(&d->bits_reader, &b);
                 while (memcmp(b.key, "SE", 2) != 0) {
+                        if (mpc_check_key(b.key) != MPC_STATUS_OK)
+                                return;
                         if (memcmp(b.key, "CT", 2) == 0) {
                                 if (d->chap_pos == 0) d->chap_pos = cur_pos;
@@ -324 +340 @@
         }
 
-        d->chap_nb = 0;
         mpc_demux_seek(d, d->chap_pos, 20);
         size = mpc_bits_get_block(&d->bits_reader, &b);
@@ -425 +440 @@
                 size = mpc_bits_get_block(&d->bits_reader, &b);
                 while( memcmp(b.key, "AP", 2) != 0 ){ // scan all blocks until audio
-                        if (b.key[0] < 65 || b.key[0] > 90 || b.key[1] < 65 || b.key[1] > 90)
+                        if (mpc_check_key(b.key) != MPC_STATUS_OK)
                                 return MPC_STATUS_INVALIDSV;
                         if (b.size > (mpc_uint64_t) DEMUX_BUFFER_SIZE - 11)
@@ -505 +520 @@
                         mpc_bits_get_block(&d->bits_reader, &b);
                         while( memcmp(b.key, "AP", 2) != 0 ) { // scan all blocks until audio
-                                if (b.key[0] < 65 || b.key[0] > 90 || b.key[1] < 65 || b.key[1] > 90)
+                                if (mpc_check_key(b.key) != MPC_STATUS_OK)
                                         goto error;
                                 if (memcmp(b.key, "SE", 2) == 0) { // end block