Change sanitize_path() to not use clean_fname() because it removes the

[rsync.git] / util.c

diff --git a/util.c b/util.c
index 59b3feb9ed273c9140dfb3969f38afe4c910573c..8c352b2b6c8ecafe223b300c29448b322ce6ff4a 100644 (file)
--- a/util.c
+++ b/util.c
@@ -581,10 +581,12 @@ void clean_fname(char *name)
 
 /*
  * Make path appear as if a chroot had occurred:
- *    0. call clean_fname on it.
  *    1. remove leading "/" (or replace with "." if at end)
  *    2. remove leading ".." components
  *    3. delete any other "<dir>/.." (recursively)
+ * While we're at it, remove double slashes and "." components like
+ *   clean_fname does(), but DON'T remove a trailing slash because that
+ *   is sometimes significant on command line arguments.
  * Return a malloc'ed copy.
  * Contributed by Dave Dykstra <dwd@bell-labs.com>
  */
@@ -593,37 +595,55 @@ char *sanitize_path(char *p)
 {
        char *copy, *copyp;
 
-       clean_fname(p);
-
        copy = (char *) malloc(strlen(p)+1);
        copyp = copy;
+       while (*p == '/') {
+               /* remove leading slashes */
+               p++;
+       }
        while (*p != '\0') {
-               if ((*p == '/') && (copyp == copy)) {
-                       /* remove leading slash */
-                       p++;
-               }
-               else if ((*p == '.') && (*(p+1) == '.') &&
+               /* this loop iterates once per filename component in p.
+                * both p (and copyp if the original had a slash) should
+                * always be left pointing after a slash
+                */
+               if ((*p == '.') && ((*(p+1) == '/') || (*(p+1) == '\0'))) {
+                       /* skip "." component */
+                       while (*++p == '/') {
+                               /* skip following slashes */
+                               ;
+                       }
+               } else if ((*p == '.') && (*(p+1) == '.') &&
                            ((*(p+2) == '/') || (*(p+2) == '\0'))) {
-                       /* remove .. followed by slash or end */
+                       /* skip ".." component followed by slash or end */
                        p += 2;
+                       if (*p == '/')
+                               p++;
                        if (copyp != copy) {
-                               /* backup the copy one level */
-                               while ((--copyp != copy) && (*copyp == '/'))
-                                       /* skip trailing slashes */
-                                       ;
-                               while ((copyp != copy) && (*copyp != '/'))
-                                       /* skip back through slash */
+                               /* back up the copy one level */
+                               --copyp; /* now pointing at slash */
+                               while ((copyp > copy) && (*(copyp - 1) != '/')) {
+                                       /* skip back up to slash */
                                        copyp--;
+                               }
                        }
                } else {
-                       /* copy one component */
                        while (1) {
+                               /* copy one component through next slash */
                                *copyp++ = *p++;
-                               if ((*p == '\0') || (*(p-1) == '/'))
+                               if ((*p == '\0') || (*(p-1) == '/')) {
+                                       while (*p == '/') {
+                                               /* skip multiple slashes */
+                                               p++;
+                                       }
                                        break;
+                               }
                        }
                }
        }
+       if (copyp == copy) {
+               /* ended up with nothing, so put in "." component */
+               *copyp++ = '.';
+       }
        *copyp = '\0';
        return(copy);
 }