dpkg: fix creation of .list files (were empty since b768aeb). Closes 5324

While at it, fix filename order and free the list of names.

function                                             old     new   delta
llist_rev                                              -      21     +21
get_header_tar                                      1733    1741      +8
unpack_package                                       587     585      -2
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/1 up/down: 29/-2)              Total: 27 bytes

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

3 files changed, 14 insertions, 6 deletions

diff --git a/archival/dpkg.c b/archival/dpkg.c
index bf9e9992c..dae8a9747 100644
--- a/archival/dpkg.c
+++ b/archival/dpkg.c
@@ -1665,20 +1665,25 @@ static void unpack_package(deb_file_t *deb_file)
         archive_handle = init_archive_deb_ar(deb_file->filename);
         init_archive_deb_data(archive_handle);
         archive_handle->dpkg__sub_archive->accept = conffile_list;
+        /* Why ARCHIVE_REMEMBER_NAMES?
+         * We want names collected in ->passed list even if conffile_list
+         * is NULL (otherwise get_header_tar may optimize name saving out):
+         */
+        archive_handle->dpkg__sub_archive->ah_flags |= ARCHIVE_REMEMBER_NAMES | ARCHIVE_UNLINK_OLD;
         archive_handle->dpkg__sub_archive->filter = filter_rename_config;
         archive_handle->dpkg__sub_archive->action_data = data_extract_all_prefix;
         archive_handle->dpkg__sub_archive->dpkg__buffer = (char*)"/"; /* huh? */
-        archive_handle->dpkg__sub_archive->ah_flags |= ARCHIVE_UNLINK_OLD;
         unpack_ar_archive(archive_handle);
 
         /* Create the list file */
         list_filename = xasprintf("/var/lib/dpkg/info/%s.%s", package_name, "list");
         out_stream = xfopen_for_write(list_filename);
+        archive_handle->dpkg__sub_archive->passed = llist_rev(archive_handle->dpkg__sub_archive->passed);
         while (archive_handle->dpkg__sub_archive->passed) {
+                char *filename = llist_pop(&archive_handle->dpkg__sub_archive->passed);
                 /* the leading . has been stripped by data_extract_all_prefix already */
-                fputs(archive_handle->dpkg__sub_archive->passed->data, out_stream);
-                fputc('\n', out_stream);
-                archive_handle->dpkg__sub_archive->passed = archive_handle->dpkg__sub_archive->passed->link;
+                fprintf(out_stream, "%s\n", filename);
+                free(filename);
         }
         fclose(out_stream);
 
diff --git a/archival/libarchive/get_header_tar.c b/archival/libarchive/get_header_tar.c
index b168653d8..bc09756ba 100644
--- a/archival/libarchive/get_header_tar.c
+++ b/archival/libarchive/get_header_tar.c
@@ -452,9 +452,11 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
                 if (cp)
                         *cp = '\0';
                 archive_handle->action_data(archive_handle);
-                if (archive_handle->accept || archive_handle->reject)
+                if (archive_handle->accept || archive_handle->reject
+                 || (archive_handle->ah_flags & ARCHIVE_REMEMBER_NAMES)
+                ) {
                         llist_add_to(&archive_handle->passed, file_header->name);
-                else /* Caller isn't interested in list of unpacked files */
+                } else /* Caller isn't interested in list of unpacked files */
                         free(file_header->name);
         } else {
                 data_skip(archive_handle);
diff --git a/include/bb_archive.h b/include/bb_archive.h
index 2043d8570..7bb5615da 100644
--- a/include/bb_archive.h
+++ b/include/bb_archive.h
@@ -121,6 +121,7 @@ typedef struct archive_handle_t {
 #define ARCHIVE_DONT_RESTORE_PERM   (1 << 6)
 #define ARCHIVE_NUMERIC_OWNER       (1 << 7)
 #define ARCHIVE_O_TRUNC             (1 << 8)
+#define ARCHIVE_REMEMBER_NAMES      (1 << 9)
 
 
 /* POSIX tar Header Block, from POSIX 1003.1-1990  */