rpm2cpio: handle LZMA compressed rpms. closes 10166

function                                             old     new   delta
rpm2cpio_main                                         78     120     +42
setup_lzma_on_fd                                       -      29     +29
fork_transformer_and_free                              -      28     +28
...
setup_unzip_on_fd                                     56      32     -24
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 3/5 up/down: 104/-67)            Total: 37 bytes

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

1 files changed, 13 insertions, 4 deletions

diff --git a/archival/rpm.c b/archival/rpm.c
index f46d88b92..cca17da33 100644
--- a/archival/rpm.c
+++ b/archival/rpm.c
@@ -56,6 +56,8 @@
 #define TAG_DIRINDEXES          1116
 #define TAG_BASENAMES           1117
 #define TAG_DIRNAMES            1118
+#define TAG_PAYLOADCOMPRESSOR   1125
+
 
 #define RPMFILE_CONFIG          (1 << 0)
 #define RPMFILE_DOC             (1 << 1)
@@ -510,6 +512,7 @@ int rpm_main(int argc, char **argv)
 int rpm2cpio_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int rpm2cpio_main(int argc UNUSED_PARAM, char **argv)
 {
+        const char *str;
         int rpm_fd;
 
         G.pagesize = getpagesize();
@@ -520,11 +523,17 @@ int rpm2cpio_main(int argc UNUSED_PARAM, char **argv)
         //      /* We need to know whether child (gzip/bzip/etc) exits abnormally */
         //      signal(SIGCHLD, check_errors_in_children);
 
-//TODO: look for rpm tag RPMTAG_PAYLOADCOMPRESSOR (dec 1125, hex 0x465),
-// if the value is "lzma", set up decompressor without detection
-// (lzma can't be detected).
+        if (ENABLE_FEATURE_SEAMLESS_LZMA
+         && (str = rpm_getstr0(TAG_PAYLOADCOMPRESSOR)) != NULL
+         && strcmp(str, "lzma") == 0
+        ) {
+                // lzma compression can't be detected
+                // set up decompressor without detection
+                setup_lzma_on_fd(rpm_fd);
+        } else {
+                setup_unzip_on_fd(rpm_fd, /*fail_if_not_compressed:*/ 1);
+        }
 
-        setup_unzip_on_fd(rpm_fd, /*fail_if_not_compressed:*/ 1);
         if (bb_copyfd_eof(rpm_fd, STDOUT_FILENO) < 0)
                 bb_error_msg_and_die("error unpacking");