5 files changed, 64 insertions, 2 deletions

diff --git a/archival/Config.in b/archival/Config.in
index 8d31ec771..160c54d64 100644
--- a/archival/Config.in
+++ b/archival/Config.in
@@ -237,7 +237,15 @@ config FEATURE_TAR_LONG_OPTIONS
         default n
         depends on TAR && GETOPT_LONG
         help
-                Enable use of long options, increases size by about 400 Bytes
+          Enable use of long options, increases size by about 400 Bytes
+
+config FEATURE_TAR_UNAME_GNAME
+        bool "Enable use of user and group names"
+        default n
+        help
+          Enables use of user and group names in tar. This affects contents
+          listings (-t) and preserving permissions when unpacking (-p).
+          +200 bytes.
 
 config UNCOMPRESS
         bool "uncompress"
diff --git a/archival/libunarchive/data_extract_all.c b/archival/libunarchive/data_extract_all.c
index 76e7edf24..4df9c09a7 100644
--- a/archival/libunarchive/data_extract_all.c
+++ b/archival/libunarchive/data_extract_all.c
@@ -112,7 +112,22 @@ void data_extract_all(archive_handle_t *archive_handle)
         }
 
         if (!(archive_handle->flags & ARCHIVE_NOPRESERVE_OWN)) {
+#if ENABLE_FEATURE_TAR_UNAME_GNAME
+                uid_t uid = file_header->uid;
+                gid_t gid = file_header->gid;
+
+                if (file_header->uname) {
+                        struct passwd *pwd = getpwnam(file_header->uname);
+                        if (pwd) uid = pwd->pw_uid;
+                }
+                if (file_header->gname) {
+                        struct group *grp = getgrnam(file_header->gname);
+                        if (grp) gid = grp->gr_gid;
+                }
+                lchown(file_header->name, uid, gid);
+#else
                 lchown(file_header->name, file_header->uid, file_header->gid);
+#endif
         }
         if ((file_header->mode & S_IFMT) != S_IFLNK) {
                 /* uclibc has no lchmod, glibc is even stranger -
diff --git a/archival/libunarchive/get_header_tar.c b/archival/libunarchive/get_header_tar.c
index 5a1f5948f..893cd5b79 100644
--- a/archival/libunarchive/get_header_tar.c
+++ b/archival/libunarchive/get_header_tar.c
@@ -187,6 +187,10 @@ char get_header_tar(archive_handle_t *archive_handle)
                 /* FIXME: what if we have non-link object with link_target? */
                 /* Will link_target be free()ed? */
         }
+#if ENABLE_FEATURE_TAR_UNAME_GNAME
+        file_header->uname = tar.uname[0] ? xstrndup(tar.uname, sizeof(tar.uname)) : NULL;
+        file_header->gname = tar.gname[0] ? xstrndup(tar.gname, sizeof(tar.gname)) : NULL;
+#endif
         file_header->mtime = GET_OCTAL(tar.mtime);
         file_header->size = GET_OCTAL(tar.size);
         file_header->gid = GET_OCTAL(tar.gid);
@@ -317,6 +321,9 @@ char get_header_tar(archive_handle_t *archive_handle)
 
         free(file_header->link_target);
         /* Do not free(file_header->name)! */
-
+#if ENABLE_FEATURE_TAR_UNAME_GNAME
+        free(file_header->uname);
+        free(file_header->gname);
+#endif
         return EXIT_SUCCESS;
 }
diff --git a/archival/libunarchive/header_verbose_list.c b/archival/libunarchive/header_verbose_list.c
index b9ac3c499..ea623ed85 100644
--- a/archival/libunarchive/header_verbose_list.c
+++ b/archival/libunarchive/header_verbose_list.c
@@ -10,6 +10,33 @@ void header_verbose_list(const file_header_t *file_header)
 {
         struct tm *mtime = localtime(&(file_header->mtime));
 
+#if ENABLE_FEATURE_TAR_UNAME_GNAME
+        char uid[8];
+        char gid[8];
+        char *user = file_header->uname;
+        char *group = file_header->gname;
+
+        if (user == NULL) {
+                snprintf(uid, sizeof(uid), "%u", (unsigned)file_header->uid);
+                user = uid;
+        }
+        if (group == NULL) {
+                snprintf(gid, sizeof(gid), "%u", (unsigned)file_header->gid);
+                group = gid;
+        }
+        printf("%s %s/%s %9u %4u-%02u-%02u %02u:%02u:%02u %s",
+                bb_mode_string(file_header->mode),
+                user,
+                group,
+                (unsigned int) file_header->size,
+                1900 + mtime->tm_year,
+                1 + mtime->tm_mon,
+                mtime->tm_mday,
+                mtime->tm_hour,
+                mtime->tm_min,
+                mtime->tm_sec,
+                file_header->name);
+#else /* !FEATURE_TAR_UNAME_GNAME */
         printf("%s %d/%d %9"OFF_FMT"u %4u-%02u-%02u %02u:%02u:%02u %s",
                 bb_mode_string(file_header->mode),
                 file_header->uid,
@@ -22,6 +49,7 @@ void header_verbose_list(const file_header_t *file_header)
                 mtime->tm_min,
                 mtime->tm_sec,
                 file_header->name);
+#endif /* FEATURE_TAR_UNAME_GNAME */
 
         if (file_header->link_target) {
                 printf(" -> %s", file_header->link_target);
diff --git a/include/unarchive.h b/include/unarchive.h
index e8beebbe1..4ed2ccd0c 100644
--- a/include/unarchive.h
+++ b/include/unarchive.h
@@ -13,6 +13,10 @@
 typedef struct file_header_t {
         char *name;
         char *link_target;
+#if ENABLE_FEATURE_TAR_UNAME_GNAME
+        char *uname; 
+        char *gname;
+#endif
         off_t size;
         uid_t uid;
         gid_t gid;