update seamless uncompression code

This change makes "tar tf hello_world.txz" work without
adding special-casing for ".txz" extension. It also removes
ever-growing magic checking code in rpm2cpio and get_header_tar -
we reuse one which lives in setup_unzip_on_fd.

function                                             old     new   delta
unpack_gz_stream                                       7     566    +559
check_signature16                                      -      70     +70
setup_unzip_on_fd                                     99     142     +43
handle_SIGCHLD                                         -      41     +41
unpack_bz2_stream                                    342     376     +34
unzip_main                                          2352    2385     +33
bbunpack                                             503     533     +30
open_transformer                                      74     102     +28
unpack_Z_stream                                     1278    1304     +26
unpack_gunzip                                        101     123     +22
init_transformer_aux_data                              -      18     +18
unpack_xz_stream                                    2388    2402     +14
open_zipped                                          131     141     +10
rpm_main                                            1358    1363      +5
get_header_tar_lzma                                   52      57      +5
get_header_tar_bz2                                    52      57      +5
unpack_lzma_stream                                  2698    2702      +4
hash_find                                            234     233      -1
get_header_tar                                      1759    1733     -26
get_header_tar_gz                                     92      57     -35
unpack_uncompress                                     51      12     -39
rpm2cpio_main                                        201     147     -54
unpack_unxz                                           67      12     -55
unpack_bz2_stream_prime                               55       -     -55
get_header_tar_Z                                      86       -     -86
unpack_gz_stream_with_info                           539       -    -539
------------------------------------------------------------------------------
(add/remove: 3/3 grow/shrink: 14/6 up/down: 947/-890)          Total: 57 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 12 insertions, 15 deletions

diff --git a/archival/libarchive/decompress_gunzip.c b/archival/libarchive/decompress_gunzip.c
index 50873e3..f1c9a79 100644
--- a/archival/libarchive/decompress_gunzip.c
+++ b/archival/libarchive/decompress_gunzip.c
@@ -1034,22 +1034,22 @@ inflate_unzip_internal(STATE_PARAM int in, int out)
 /* For unzip */
 
 IF_DESKTOP(long long) int FAST_FUNC
-inflate_unzip(inflate_unzip_result *res, off_t compr_size, int in, int out)
+inflate_unzip(transformer_aux_data_t *aux, int in, int out)
 {
 	IF_DESKTOP(long long) int n;
 	DECLARE_STATE;
 
 	ALLOC_STATE;
 
-	to_read = compr_size;
+	to_read = aux->bytes_in;
 //	bytebuffer_max = 0x8000;
 	bytebuffer_offset = 4;
 	bytebuffer = xmalloc(bytebuffer_max);
 	n = inflate_unzip_internal(PASS_STATE in, out);
 	free(bytebuffer);
 
-	res->crc = gunzip_crc;
-	res->bytes_out = gunzip_bytes_out;
+	aux->crc32 = gunzip_crc;
+	aux->bytes_out = gunzip_bytes_out;
 	DEALLOC_STATE;
 	return n;
 }
@@ -1107,7 +1107,7 @@ static uint32_t buffer_read_le_u32(STATE_PARAM_ONLY)
 	return res;
 }
 
-static int check_header_gzip(STATE_PARAM unpack_info_t *info)
+static int check_header_gzip(STATE_PARAM transformer_aux_data_t *aux)
 {
 	union {
 		unsigned char raw[8];
@@ -1169,8 +1169,8 @@ static int check_header_gzip(STATE_PARAM unpack_info_t *info)
 		}
 	}
 
-	if (info)
-		info->mtime = SWAP_LE32(header.formatted.mtime);
+	if (aux)
+		aux->mtime = SWAP_LE32(header.formatted.mtime);
 
 	/* Read the header checksum */
 	if (header.formatted.flags & 0x02) {
@@ -1182,12 +1182,15 @@ static int check_header_gzip(STATE_PARAM unpack_info_t *info)
 }
 
 IF_DESKTOP(long long) int FAST_FUNC
-unpack_gz_stream_with_info(int src_fd, int dst_fd, unpack_info_t *info)
+unpack_gz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
 {
 	uint32_t v32;
 	IF_DESKTOP(long long) int total, n;
 	DECLARE_STATE;
 
+	if (check_signature16(aux, src_fd, GZIP_MAGIC))
+		return -1;
+
 	total = 0;
 
 	ALLOC_STATE;
@@ -1197,7 +1200,7 @@ unpack_gz_stream_with_info(int src_fd, int dst_fd, unpack_info_t *info)
 	gunzip_src_fd = src_fd;
 
  again:
-	if (!check_header_gzip(PASS_STATE info)) {
+	if (!check_header_gzip(PASS_STATE aux)) {
 		bb_error_msg("corrupted data");
 		total = -1;
 		goto ret;
@@ -1248,9 +1251,3 @@ unpack_gz_stream_with_info(int src_fd, int dst_fd, unpack_info_t *info)
 	DEALLOC_STATE;
 	return total;
 }
-
-IF_DESKTOP(long long) int FAST_FUNC
-unpack_gz_stream(int in, int out)
-{
-	return unpack_gz_stream_with_info(in, out, NULL);
-}