Btrfs-progs: move path modification to filters

Commit 8e8e019e910f20947fea7eff5da40753639d8870 introduces -a option
which will list all subvolumes with distinguishing between relative and
absolute by prepending absolute patch with "<FS_TREE>".

This commit moves the path modification to a filter code rather than
doing so in path construction in resolve_root(). This gives us more
flexibility in formatting path output.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>

diff --git a/btrfs-list.c b/btrfs-list.c
index e09ee2d..1429dd9 100644 (file)
--- a/btrfs-list.c
+++ b/btrfs-list.c
@@ -628,16 +628,6 @@ static int resolve_root(struct root_lookup *rl, struct root_info *ri,
                }
 
                if (next == BTRFS_FS_TREE_OBJECTID) {
-                       char p[] = "<FS_TREE>";
-                       add_len = strlen(p);
-                       len = strlen(full_path);
-                       tmp = malloc(len + add_len + 2);
-                       memcpy(tmp + add_len + 1, full_path, len);
-                       tmp[len + add_len + 1] = '\0';
-                       tmp[add_len] = '/';
-                       memcpy(tmp, p, add_len);
-                       free(full_path);
-                       full_path = tmp;
                        ri->top_id = next;
                        break;
                }
@@ -1175,6 +1165,29 @@ static int filter_topid_equal(struct root_info *ri, u64 data)
        return ri->top_id == data;
 }
 
+static int filter_full_path(struct root_info *ri, u64 data)
+{
+       if (ri->full_path && ri->top_id != data) {
+               char *tmp;
+               char p[] = "<FS_TREE>";
+               int add_len = strlen(p);
+               int len = strlen(ri->full_path);
+
+               tmp = malloc(len + add_len + 2);
+               if (!tmp) {
+                       fprintf(stderr, "memory allocation failed\n");
+                       exit(1);
+               }
+               memcpy(tmp + add_len + 1, ri->full_path, len);
+               tmp[len + add_len + 1] = '\0';
+               tmp[add_len] = '/';
+               memcpy(tmp, p, add_len);
+               free(ri->full_path);
+               ri->full_path = tmp;
+       }
+       return 1;
+}
+
 static btrfs_list_filter_func all_filter_funcs[] = {
        [BTRFS_LIST_FILTER_ROOTID]              = filter_by_rootid,
        [BTRFS_LIST_FILTER_SNAPSHOT_ONLY]       = filter_snapshot,
@@ -1186,6 +1199,7 @@ static btrfs_list_filter_func all_filter_funcs[] = {
        [BTRFS_LIST_FILTER_CGEN_LESS]           = filter_cgen_less,
        [BTRFS_LIST_FILTER_CGEN_EQUAL]          = filter_cgen_equal,
        [BTRFS_LIST_FILTER_TOPID_EQUAL]         = filter_topid_equal,
+       [BTRFS_LIST_FILTER_FULL_PATH]           = filter_full_path,
 };
 
 struct btrfs_list_filter_set *btrfs_list_alloc_filter_set(void)

diff --git a/btrfs-list.h b/btrfs-list.h
index cde4b3c..f7fbea6 100644 (file)
--- a/btrfs-list.h
+++ b/btrfs-list.h
@@ -71,6 +71,7 @@ enum btrfs_list_filter_enum {
        BTRFS_LIST_FILTER_CGEN_LESS,
        BTRFS_LIST_FILTER_CGEN_MORE,
        BTRFS_LIST_FILTER_TOPID_EQUAL,
+       BTRFS_LIST_FILTER_FULL_PATH,
        BTRFS_LIST_FILTER_MAX,
 };
 

diff --git a/cmds-subvolume.c b/cmds-subvolume.c
index e3cdb1e..1f29ed3 100644 (file)
--- a/cmds-subvolume.c
+++ b/cmds-subvolume.c
@@ -278,7 +278,9 @@ static const char * const cmd_subvol_list_usage[] = {
        "List subvolumes (and snapshots)",
        "",
        "-p           print parent ID",
-       "-a           print all the subvolumes in the filesystem.",
+       "-a           print all the subvolumes in the filesystem and",
+       "             distinguish absolute and relative path with respect",
+       "             to the given <path>",
        "-u           print the uuid of subvolumes (and snapshots)",
        "-t           print the result as a table",
        "-s           list snapshots only in the filesystem",
@@ -401,7 +403,12 @@ static int cmd_subvol_list(int argc, char **argv)
        }
 
        top_id = btrfs_list_get_path_rootid(fd);
-       if (!is_list_all)
+
+       if (is_list_all)
+               btrfs_list_setup_filter(&filter_set,
+                                       BTRFS_LIST_FILTER_FULL_PATH,
+                                       top_id);
+       else
                btrfs_list_setup_filter(&filter_set,
                                        BTRFS_LIST_FILTER_TOPID_EQUAL,
                                        top_id);

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 054fce0..d856b82 100644 (file)
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -130,7 +130,8 @@ and top level. The parent's ID may be used at mount time via the
 
 \fB-t\fP print the result as a table.
 
-\fB-a\fP print all the subvolumes in the filesystem.
+\fB-a\fP print all the subvolumes in the filesystem and distinguish between
+absolute and relative path with respect to the given <path>.
 
 \fB-r\fP only readonly subvolumes in the filesystem wille be listed.