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authorLasse Collin <lasse.collin@tukaani.org>2013-02-27 16:26:40 (GMT)
committer Denys Vlasenko <vda.linux@googlemail.com>2013-02-27 16:26:40 (GMT)
commit380c8a0763462692eef8d00df4872a561ff7aa7b (patch)
treee336c964ef716563e2115b1a5bfb11d4e75e883f
parent433757413f55986681f29ab1335e514e9f0c8423 (diff)
downloadbusybox-380c8a0763462692eef8d00df4872a561ff7aa7b.tar.gz
busybox-380c8a0763462692eef8d00df4872a561ff7aa7b.tar.bz2
xz: support concatenated .xz streams
function old new delta xz_dec_reset - 77 +77 unpack_xz_stream 2402 2397 -5 Signed-off-by: Lasse Collin <lasse.collin@tukaani.org> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--archival/libarchive/decompress_unxz.c43
1 files changed, 36 insertions, 7 deletions
diff --git a/archival/libarchive/decompress_unxz.c b/archival/libarchive/decompress_unxz.c
index 79b48a1..e9ddd37 100644
--- a/archival/libarchive/decompress_unxz.c
+++ b/archival/libarchive/decompress_unxz.c
@@ -40,6 +40,7 @@ static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc)
IF_DESKTOP(long long) int FAST_FUNC
unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
{
+ enum xz_ret xz_result;
struct xz_buf iobuf;
struct xz_dec *state;
unsigned char *membuf;
@@ -63,9 +64,8 @@ unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
/* Limit memory usage to about 64 MiB. */
state = xz_dec_init(XZ_DYNALLOC, 64*1024*1024);
+ xz_result = X_OK;
while (1) {
- enum xz_ret r;
-
if (iobuf.in_pos == iobuf.in_size) {
int rd = safe_read(src_fd, membuf, BUFSIZ);
if (rd < 0) {
@@ -73,28 +73,57 @@ unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
total = -1;
break;
}
+ if (rd == 0 && xz_result == XZ_STREAM_END)
+ break;
iobuf.in_size = rd;
iobuf.in_pos = 0;
}
+ if (xz_result == XZ_STREAM_END) {
+ /*
+ * Try to start decoding next concatenated stream.
+ * Stream padding must always be a multiple of four
+ * bytes to preserve four-byte alignment. To keep the
+ * code slightly smaller, we aren't as strict here as
+ * the .xz spec requires. We just skip all zero-bytes
+ * without checking the alignment and thus can accept
+ * files that aren't valid, e.g. the XZ utils test
+ * files bad-0pad-empty.xz and bad-0catpad-empty.xz.
+ */
+ do {
+ if (membuf[iobuf.in_pos] != 0) {
+ xz_dec_reset(state);
+ goto do_run;
+ }
+ iobuf.in_pos++;
+ } while (iobuf.in_pos < iobuf.in_size);
+ }
+ do_run:
// bb_error_msg(">in pos:%d size:%d out pos:%d size:%d",
// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size);
- r = xz_dec_run(state, &iobuf);
+ xz_result = xz_dec_run(state, &iobuf);
// bb_error_msg("<in pos:%d size:%d out pos:%d size:%d r:%d",
-// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, r);
+// iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, xz_result);
if (iobuf.out_pos) {
xwrite(dst_fd, iobuf.out, iobuf.out_pos);
IF_DESKTOP(total += iobuf.out_pos;)
iobuf.out_pos = 0;
}
- if (r == XZ_STREAM_END) {
- break;
+ if (xz_result == XZ_STREAM_END) {
+ /*
+ * Can just "break;" here, if not for concatenated
+ * .xz streams.
+ * Checking for padding may require buffer
+ * replenishment. Can't do it here.
+ */
+ continue;
}
- if (r != XZ_OK && r != XZ_UNSUPPORTED_CHECK) {
+ if (xz_result != XZ_OK && xz_result != XZ_UNSUPPORTED_CHECK) {
bb_error_msg("corrupted data");
total = -1;
break;
}
}
+
xz_dec_end(state);
free(membuf);