diff options
| -rw-r--r-- | lib/xz/xz_dec_bcj.c | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/lib/xz/xz_dec_bcj.c b/lib/xz/xz_dec_bcj.c index e51e2558ca9d..a768e6d28bbb 100644 --- a/lib/xz/xz_dec_bcj.c +++ b/lib/xz/xz_dec_bcj.c @@ -441,8 +441,12 @@ XZ_EXTERN enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s, * next filter in the chain. Apply the BCJ filter on the new data * in the output buffer. If everything cannot be filtered, copy it * to temp and rewind the output buffer position accordingly. + * + * This needs to be always run when temp.size == 0 to handle a special + * case where the output buffer is full and the next filter has no + * more output coming but hasn't returned XZ_STREAM_END yet. */ - if (s->temp.size < b->out_size - b->out_pos) { + if (s->temp.size < b->out_size - b->out_pos || s->temp.size == 0) { out_start = b->out_pos; memcpy(b->out + b->out_pos, s->temp.buf, s->temp.size); b->out_pos += s->temp.size; @@ -465,16 +469,25 @@ XZ_EXTERN enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s, s->temp.size = b->out_pos - out_start; b->out_pos -= s->temp.size; memcpy(s->temp.buf, b->out + b->out_pos, s->temp.size); + + /* + * If there wasn't enough input to the next filter to fill + * the output buffer with unfiltered data, there's no point + * to try decoding more data to temp. + */ + if (b->out_pos + s->temp.size < b->out_size) + return XZ_OK; } /* - * If we have unfiltered data in temp, try to fill by decoding more - * data from the next filter. Apply the BCJ filter on temp. Then we - * hopefully can fill the actual output buffer by copying filtered - * data from temp. A mix of filtered and unfiltered data may be left - * in temp; it will be taken care on the next call to this function. + * We have unfiltered data in temp. If the output buffer isn't full + * yet, try to fill the temp buffer by decoding more data from the + * next filter. Apply the BCJ filter on temp. Then we hopefully can + * fill the actual output buffer by copying filtered data from temp. + * A mix of filtered and unfiltered data may be left in temp; it will + * be taken care on the next call to this function. */ - if (s->temp.size > 0) { + if (b->out_pos < b->out_size) { /* Make b->out{,_pos,_size} temporarily point to s->temp. */ s->out = b->out; s->out_pos = b->out_pos; |