Even if the utils_expand_path function was intended to allow to
use unexistent directory paths, it was in fact only working for
some kind of arguments. Paths like "foo", "bar/" or "bar/foo"
when the "bar" directory does not exist wasn't working. This
patch introduce a new way to expand paths in this function that
also works properly for these kind of arguments.

Signed-off-by: Raphaël Beamonte <[email protected]>
---
 src/common/utils.c |   72 +++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 51 insertions(+), 21 deletions(-)

diff --git a/src/common/utils.c b/src/common/utils.c
index 7b52760..b68f12e 100644
--- a/src/common/utils.c
+++ b/src/common/utils.c
@@ -92,7 +92,7 @@ int utils_resolve_relative(char *path)
 LTTNG_HIDDEN
 char *utils_expand_path(const char *path)
 {
-       const char *end_path = path;
+       const char *end_path = NULL;
        char *next, *cut_path = NULL, *expanded_path = NULL;
 
        /* Safety net */
@@ -100,35 +100,65 @@ char *utils_expand_path(const char *path)
                goto error;
        }
 
-       /* Find last token delimited by '/' */
-       while ((next = strpbrk(end_path + 1, "/"))) {
-               end_path = next;
-       }
-
-       /* Cut last token from original path */
-       cut_path = strndup(path, end_path - path);
-
+       /* Allocate memory for the expanded path */
        expanded_path = zmalloc(PATH_MAX);
        if (expanded_path == NULL) {
                PERROR("zmalloc expand path");
                goto error;
        }
 
-       expanded_path = realpath((char *)cut_path, expanded_path);
-       if (expanded_path == NULL) {
-               switch (errno) {
-               case ENOENT:
-                       ERR("%s: No such file or directory", cut_path);
-                       break;
-               default:
-                       PERROR("realpath utils expand path");
-                       break;
+       /* If given path is already absolute */
+       if (*path == '/') {
+               strncpy(expanded_path, path, PATH_MAX);
+       /* Else, we have some work to do */
+       } else {
+               /* Pointer to the last char of the path */
+               const char *last_char = path+strlen(path)-1;
+
+               end_path = path;
+               /* If the path is just a directory name */
+               if (strchr(path, '/') == NULL || strchr(path, '/') == 
last_char) {
+                       cut_path = strdup(".");
+               /* Else, we have to analyse the full path */
+               } else {
+                       /* Split part that will be resolved by realpath 
(relative path from
+                        * current directory using ./ or ../ only) and part 
that could not
+                        * (directory names)
+                        */
+                       while ((next = strpbrk(end_path, "/")) && (next != 
last_char)) {
+                               end_path = next + 1;
+                               if (strncmp(end_path, "./", 2) != 0 && 
strncmp(end_path, "../", 3) != 0) {
+                                       break;
+                               }
+                       }
+
+                       /* Cut last token from original path */
+                       cut_path = strndup(path, end_path - path);
                }
-               goto error;
+
+               /* Resolve the canonical path of the first part of the path */
+               expanded_path = realpath((char *)cut_path, expanded_path);
+               if (expanded_path == NULL) {
+                       switch (errno) {
+                       case ENOENT:
+                               ERR("%s: No such file or directory", cut_path);
+                               break;
+                       default:
+                               PERROR("realpath utils expand path");
+                               break;
+                       }
+                       goto error;
+               }
+
+               /* Add end part to expanded path */
+               strncat(expanded_path, "/", PATH_MAX - strlen(expanded_path) - 
1);
+               strncat(expanded_path, end_path, PATH_MAX - 
strlen(expanded_path) - 1);
        }
 
-       /* Add end part to expanded path */
-       strncat(expanded_path, end_path, PATH_MAX - strlen(expanded_path) - 1);
+       /* Resolve the internal './' and '../' strings */
+       if (utils_resolve_relative(expanded_path) != 0) {
+               goto error;
+       }
 
        free(cut_path);
        return expanded_path;
-- 
1.7.10.4


_______________________________________________
lttng-dev mailing list
[email protected]
http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev

Reply via email to