Move seamless .Z support into unpack_gz_stream

unpack_gz_stream                                     566     643     +77
unpack_gunzip                                        123      12    -111

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

3 files changed, 21 insertions, 25 deletions

diff --git a/archival/Config.src b/archival/Config.src
index 885cb5bcc..ae1afc594 100644
--- a/archival/Config.src
+++ b/archival/Config.src
@@ -32,10 +32,10 @@ config FEATURE_SEAMLESS_GZ
           Make tar, rpm, modprobe etc understand .gz data.
 
 config FEATURE_SEAMLESS_Z
-        bool "Make tar and gunzip understand .Z data"
+        bool "tar, rpm, modprobe etc understand .Z data"
         default n
         help
-          Make tar and gunzip understand .Z data.
+          Make tar, rpm, modprobe etc understand .Z data.
 
 config AR
         bool "ar"
diff --git a/archival/bbunzip.c b/archival/bbunzip.c
index 1bc04ed33..94d8a81c9 100644
--- a/archival/bbunzip.c
+++ b/archival/bbunzip.c
@@ -274,29 +274,7 @@ char* FAST_FUNC make_new_name_gunzip(char *filename, const char *expected_ext UN
 static
 IF_DESKTOP(long long) int FAST_FUNC unpack_gunzip(transformer_aux_data_t *aux)
 {
-        IF_DESKTOP(long long) int status = -1;
-        uint16_t magic2;
-
-//TODO: fold below into unpack_gz_stream? Then the whole level of indirection
-// unpack_FOO() -> unpack_FOO_stream can be collapsed in this module!
-
-        aux->check_signature = 0; /* we will check it here, not in unpack_*_stream */
-
-        if (full_read(STDIN_FILENO, &magic2, 2) != 2)
-                goto bad_magic;
-        if (ENABLE_FEATURE_SEAMLESS_Z && magic2 == COMPRESS_MAGIC) {
-                status = unpack_Z_stream(aux, STDIN_FILENO, STDOUT_FILENO);
-        } else if (magic2 == GZIP_MAGIC) {
-                status = unpack_gz_stream(aux, STDIN_FILENO, STDOUT_FILENO);
-        } else {
- bad_magic:
-                bb_error_msg("invalid magic");
-                /* status is still == -1 */
-        }
-        if (status < 0) {
-                bb_error_msg("error inflating");
-        }
-        return status;
+        return unpack_gz_stream(aux, STDIN_FILENO, STDOUT_FILENO);
 }
 /*
  * Linux kernel build uses gzip -d -n. We accept and ignore it.
diff --git a/archival/libarchive/decompress_gunzip.c b/archival/libarchive/decompress_gunzip.c
index f1c9a79e5..66152a853 100644
--- a/archival/libarchive/decompress_gunzip.c
+++ b/archival/libarchive/decompress_gunzip.c
@@ -1188,8 +1188,26 @@ unpack_gz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
         IF_DESKTOP(long long) int total, n;
         DECLARE_STATE;
 
+#if !ENABLE_FEATURE_SEAMLESS_Z
         if (check_signature16(aux, src_fd, GZIP_MAGIC))
                 return -1;
+#else
+        if (aux && aux->check_signature) {
+                uint16_t magic2;
+
+                if (full_read(STDIN_FILENO, &magic2, 2) != 2) {
+ bad_magic:
+                        bb_error_msg("invalid magic");
+                        return -1;
+                }
+                if (magic2 == COMPRESS_MAGIC) {
+                        aux->check_signature = 0;
+                        return unpack_Z_stream(aux, src_fd, dst_fd);
+                }
+                if (magic2 != GZIP_MAGIC)
+                        goto bad_magic;
+        }
+#endif
 
         total = 0;