commit 5fd7d3a23316ec0d2320fece85201859b52c2aef
author Marco Nelissen <marcone@google.com> Wed Jun 13 08:51:00 2012 -0700
committer Marco Nelissen <marcone@google.com> Wed Jun 13 16:29:52 2012 -0700
tree eb812fe337a080a3f3709e2fbbd992813bc5583c
parent b4ea1ab821d652cb080910d4081f5f1318597a90

Better handle invalid duration in Xing/VBRI tags

b/6654637

Change-Id: Ie92eddd84ef5914b77dbadaacd80b4de6cd66e1c

media/libstagefright/XINGSeeker.cpp

diff --git a/media/libstagefright/XINGSeeker.cpp b/media/libstagefright/XINGSeeker.cpp
index 9c91134..81ed9c6 100644
--- a/media/libstagefright/XINGSeeker.cpp
+++ b/media/libstagefright/XINGSeeker.cpp
@@ -29,7 +29,8 @@
     : mDurationUs(-1),
       mSizeBytes(0),
       mEncoderDelay(0),
-      mEncoderPadding(0) {
+      mEncoderPadding(0),
+      mTOCValid(false) {
 }
 
 bool XINGSeeker::getDuration(int64_t *durationUs) {
@@ -81,10 +82,6 @@
 
     seeker->mFirstFramePos = first_frame_pos;
 
-    seeker->mSizeBytes = 0;
-    seeker->mTOCValid = false;
-    seeker->mDurationUs = 0;
-
     uint8_t buffer[4];
     int offset = first_frame_pos;
     if (source->readAt(offset, &buffer, 4) < 4) { // get header
@@ -140,7 +137,13 @@
              return NULL;
         }
         int32_t frames = U32_AT(buffer);
-        seeker->mDurationUs = (int64_t)frames * samples_per_frame * 1000000LL / sampling_rate;
+        // only update mDurationUs if the calculated duration is valid (non zero)
+        // otherwise, leave duration at -1 so that getDuration() and getOffsetForTime()
+        // return false when called, to indicate that this xing tag does not have the
+        // requested information
+        if (frames) {
+            seeker->mDurationUs = (int64_t)frames * samples_per_frame * 1000000LL / sampling_rate;
+        }
         offset += 4;
     }
     if (flags & 0x0002) {  // Bytes field is present