On Wed, Mar 18, 2015 at 02:21:31PM +0100, Maros Zatko wrote:
First it strips /sysroot and then finds common prefix aligned
on slashes. Next it produces ../ for each slash found in common
prefix and concatenates them with the rest of resolved link.
Fixes RHBZ#604041
---
src/fuse.c | 33 ++++++++++++++++++++++++++++++++-
1 file changed, 32 insertions(+), 1 deletion(-)
diff --git a/src/fuse.c b/src/fuse.c
index 3fdb1d4..6c7eee1 100644
--- a/src/fuse.c
+++ b/src/fuse.c
@@ -386,7 +386,38 @@ mount_local_readlink (const char *path, char *buf, size_t size)
if (len > size - 1)
len = size - 1;
- memcpy (buf, r, len);
+ buf[0] = '\0';
+ size_t offset = 0;
+ if (STRPREFIX (r, "/sysroot")) {
+ offset = strlen ("/sysroot") + 1;
+ size_t i;
+ for (i = 0; (i < strlen (r+offset)) && (path[i] == r[i+offset-1]); i++);
+ /* Now i contains index where paths starts to differ
+ * (n.b. needs to be aligned on last slash). */
+
+ for (; path[i] != '/'; --i);
+ /* i is now aligned */
+
+ /* Count slashes in original path, so we can generate
+ * right amount of ../ */
+ size_t j; int cnt = 0;
+ for (j = i+1; j < strlen (r+offset); j++) {
+ if (path[j] == '/') cnt++;
+ }
+
+ /* For each slash create ../ in path */
+ for (int z = 0; z < cnt; z++) {
+ strcat (buf, "../");
+ }
+
+ /* In addition to /sysroot ne need to remove common path
+ * aligned on slashes */
+ offset += i;
+ }
+
+ /* There might already be something in buf (such as ../)
+ * so let's concatenate the rest of path */
+ strncat (buf, r + offset, len - offset + 1);
buf[len] = '\0';
This makes my head hurt. Perhaps some diagrams or examples
of how this is supposed to work?
Rich.
--
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