Fix seeking in large raw DV files

start_pos is of type off_t, and since we compile with D_FILE_OFFSET_BITS=64,
-off_t is a 64-bit long long int, so you'd think we'd be fine here -- but we
aren't, because start_time, this->duration and this->frame_size are all
32-bit ints, which means that the computed seek position gets truncated to
32 bits before it's assigned to start_pos. The simple solution is to cast
start_time to off_t, expanding the computation to 64 bits in time to avoid
truncation.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/demuxers/demux_rawdv.c b/src/demuxers/demux_rawdv.c
index 86f777ec6..d95fc9125 100644
--- a/src/demuxers/demux_rawdv.c
+++ b/src/demuxers/demux_rawdv.c
@@ -302,7 +302,8 @@ static int demux_raw_dv_seek (demux_plugin_t *this_gen,
   }
 
   if( !start_pos && start_time ) {
-    start_pos = (start_time * 90 / this->duration) * this->frame_size;
+    /* Upcast start_time in case sizeof(off_t) > sizeof(int) */
+    start_pos = ((off_t) start_time * 90 / this->duration) * this->frame_size;
   }
   
   start_pos = start_pos - (start_pos % this->frame_size);