losetup: make -j <path> more robust

It's usually unnecessary as we compare devno and ino, but let's
use absolute paths for situations when it's necessary to compare
paths as strings.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/sys-utils/losetup.c b/sys-utils/losetup.c
index 1bd1f41a44008775912bf7be9e078a2469ce41ba..217cf9c18a87d6ed8cb9790001b56bc9387c43c0 100644 (file)
--- a/sys-utils/losetup.c
+++ b/sys-utils/losetup.c
@@ -160,6 +160,7 @@ static int show_all_loops(struct loopdev_cxt *lc, const char *file,
                          uint64_t offset, int flags)
 {
        struct stat sbuf, *st = &sbuf;
+       char *cn_file = NULL;
 
        if (loopcxt_init_iterator(lc, LOOPITER_FL_USED))
                return -1;
@@ -168,18 +169,23 @@ static int show_all_loops(struct loopdev_cxt *lc, const char *file,
                st = NULL;
 
        while (loopcxt_next(lc) == 0) {
-               if (file && !loopcxt_is_used(lc, st, file, offset, flags)) {
-                       char *canonized;
-                       int ret;
-                       canonized = canonicalize_path(file);
-                       ret = loopcxt_is_used(lc, st, canonized, offset, flags);
-                       free(canonized);
-                       if (!ret)
+               if (file) {
+                       int used;
+                       const char *bf = cn_file ? cn_file : file;
+
+                       used = loopcxt_is_used(lc, st, bf, offset, flags);
+                       if (!used && !cn_file) {
+                               bf = cn_file = canonicalize_path(file);
+                               used = loopcxt_is_used(lc, st, bf, offset, flags);
+                       }
+                       if (!used)
                                continue;
                }
                printf_loopdev(lc);
        }
        loopcxt_deinit_iterator(lc);
+       if (cn_file)
+               free(cn_file);
        return 0;
 }
 
@@ -298,6 +304,7 @@ static int make_table(struct loopdev_cxt *lc,
 {
        struct stat sbuf, *st = &sbuf;
        struct tt_line *ln;
+       char *cn_file = NULL;
        int i;
 
        if (!(tt = tt_new_table(tt_flags)))
@@ -325,9 +332,18 @@ static int make_table(struct loopdev_cxt *lc,
                st = NULL;
 
        while (loopcxt_next(lc) == 0) {
-               if (file && !loopcxt_is_used(lc, st, file, offset, flags))
-                       continue;
-
+               if (file) {
+                       int used;
+                       const char *bf = cn_file ? cn_file : file;
+
+                       used = loopcxt_is_used(lc, st, bf, offset, flags);
+                       if (!used && !cn_file) {
+                               bf = cn_file = canonicalize_path(file);
+                               used = loopcxt_is_used(lc, st, bf, offset, flags);
+                       }
+                       if (!used)
+                               continue;
+               }
 
                ln = tt_add_line(tt, NULL);
                if (set_tt_data(lc, ln))
@@ -335,6 +351,8 @@ static int make_table(struct loopdev_cxt *lc,
        }
 
        loopcxt_deinit_iterator(lc);
+       if (cn_file)
+               free(cn_file);
        return 0;
 }