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

[rsync/rsync.git] / util.c

diff --git a/util.c b/util.c
index 001694b..8c352b2 100644 (file)
--- a/util.c
+++ b/util.c
@@ -579,6 +579,75 @@ void clean_fname(char *name)
        }
 }
 
+/*
+ * Make path appear as if a chroot had occurred:
+ *    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>
+ */
+
+char *sanitize_path(char *p)
+{
+       char *copy, *copyp;
+
+       copy = (char *) malloc(strlen(p)+1);
+       copyp = copy;
+       while (*p == '/') {
+               /* remove leading slashes */
+               p++;
+       }
+       while (*p != '\0') {
+               /* 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'))) {
+                       /* skip ".." component followed by slash or end */
+                       p += 2;
+                       if (*p == '/')
+                               p++;
+                       if (copyp != copy) {
+                               /* back up the copy one level */
+                               --copyp; /* now pointing at slash */
+                               while ((copyp > copy) && (*(copyp - 1) != '/')) {
+                                       /* skip back up to slash */
+                                       copyp--;
+                               }
+                       }
+               } else {
+                       while (1) {
+                               /* copy one component through next slash */
+                               *copyp++ = *p++;
+                               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);
+}
+
 
 static char curr_dir[MAXPATHLEN];
 
@@ -716,52 +785,6 @@ int unsafe_symlink(char *dest, char *src)
        return (depth < 0);
 }
 
-/*
- * Make path appear as if a chroot had occurred:
- *    1. remove leading "/" (or replace with "." if at end)
- *    2. remove leading ".." components
- *    3. delete any other "<dir>/.." (recursively)
- * Return a malloc'ed copy.
- * Contributed by Dave Dykstra <dwd@bell-labs.com>
- */
-
-char *sanitize_path(char *p)
-{
-       char *copy, *copyp;
-
-       copy = (char *) malloc(strlen(p)+1);
-       copyp = copy;
-       while (*p != '\0') {
-               if ((*p == '/') && (copyp == copy)) {
-                       /* remove leading slash */
-                       p++;
-               }
-               else if ((*p == '.') && (*(p+1) == '.') &&
-                           ((*(p+2) == '/') || (*(p+2) == '\0'))) {
-                       /* remove .. followed by slash or end */
-                       p += 2;
-                       if (copyp != copy) {
-                               /* backup the copy one level */
-                               while ((--copyp != copy) && (*copyp == '/'))
-                                       /* skip trailing slashes */
-                                       ;
-                               while ((copyp != copy) && (*copyp != '/'))
-                                       /* skip back through slash */
-                                       copyp--;
-                       }
-               } else {
-                       /* copy one component */
-                       while (1) {
-                               *copyp++ = *p++;
-                               if ((*p == '\0') || (*(p-1) == '/'))
-                                       break;
-                       }
-               }
-       }
-       *copyp = '\0';
-       return(copy);
-}
-
 
 /****************************************************************************
   return the date and time as a string