util: rework cunescape(), improve error handling

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index 973f1070b8a1178ee4796a03ecdca2872f3cf5af..a8e485cc9c805f9647417fc23bbcf692cfc60c8a 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -1487,12 +1487,13 @@ static int cunescape_one(const char *p, size_t length, char *ret) {
         return r;
 }
 
         return r;
 }
 

-char *cunescape_length_with_prefix(const char *s, size_t length, const char *prefix) {
+int cunescape_length_with_prefix(const char *s, size_t length, const char *prefix, UnescapeFlags flags, char **ret) {

         char *r, *t;
         const char *f;
         size_t pl;
 
         assert(s);
         char *r, *t;
         const char *f;
         size_t pl;
 
         assert(s);

+        assert(ret);

 
         /* Undoes C style string escaping, and optionally prefixes it. */
 
 
         /* Undoes C style string escaping, and optionally prefixes it. */
 


@@ -1500,7 +1501,7 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
 
         r = new(char, pl+length+1);
         if (!r)
 
         r = new(char, pl+length+1);
         if (!r)

-                return NULL;
+                return -ENOMEM;

 
         if (prefix)
                 memcpy(r, prefix, pl);
 
         if (prefix)
                 memcpy(r, prefix, pl);


@@ -1512,17 +1513,31 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
                 remaining = s + length - f;
                 assert(remaining > 0);
 
                 remaining = s + length - f;
                 assert(remaining > 0);
 

-                if (*f != '\\' || remaining == 1) {
-                        /* a literal literal, or a trailing backslash, copy verbatim */
+                if (*f != '\\') {
+                        /* A literal literal, copy verbatim */

                         *(t++) = *f;
                         continue;
                 }
 
                         *(t++) = *f;
                         continue;
                 }
 

+                if (remaining == 1) {
+                        if (flags & UNESCAPE_RELAX) {
+                                /* A trailing backslash, copy verbatim */
+                                *(t++) = *f;
+                                continue;
+                        }
+
+                        return -EINVAL;
+                }
+

                 k = cunescape_one(f + 1, remaining - 1, t);
                 if (k < 0) {
                 k = cunescape_one(f + 1, remaining - 1, t);
                 if (k < 0) {

-                        /* Invalid escape code, let's take it literal then */
-                        *(t++) = '\\';
-                        continue;
+                        if (flags & UNESCAPE_RELAX) {
+                                /* Invalid escape code, let's take it literal then */
+                                *(t++) = '\\';
+                                continue;
+                        }
+
+                        return k;

                 }
 
                 f += k;
                 }
 
                 f += k;


@@ -1530,17 +1545,17 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
         }
 
         *t = 0;
         }
 
         *t = 0;

-        return r;
-}

 
 

-char *cunescape_length(const char *s, size_t length) {
-        return cunescape_length_with_prefix(s, length, NULL);
+        *ret = r;
+        return t - r;

 }
 
 }
 

-char *cunescape(const char *s) {
-        assert(s);
+int cunescape_length(const char *s, size_t length, UnescapeFlags flags, char **ret) {
+        return cunescape_length_with_prefix(s, length, NULL, flags, ret);
+}

 
 

-        return cunescape_length(s, strlen(s));
+int cunescape(const char *s, UnescapeFlags flags, char **ret) {
+        return cunescape_length(s, strlen(s), flags, ret);

 }
 
 char *xescape(const char *s, const char *bad) {
 }
 
 char *xescape(const char *s, const char *bad) {


@@ -6752,9 +6767,9 @@ int umount_recursive(const char *prefix, int flags) {
                                 continue;
                         }
 
                                 continue;
                         }
 

-                        p = cunescape(path);
-                        if (!p)
-                                return -ENOMEM;
+                        r = cunescape(path, UNESCAPE_RELAX, &p);
+                        if (r < 0)
+                                return r;

 
                         if (!path_startswith(p, prefix))
                                 continue;
 
                         if (!path_startswith(p, prefix))
                                 continue;


@@ -6854,9 +6869,9 @@ int bind_remount_recursive(const char *prefix, bool ro) {
                                 continue;
                         }
 
                                 continue;
                         }
 

-                        p = cunescape(path);
-                        if (!p)
-                                return -ENOMEM;
+                        r = cunescape(path, UNESCAPE_RELAX, &p);
+                        if (r < 0)
+                                return r;

 
                         /* Let's ignore autofs mounts.  If they aren't
                          * triggered yet, we want to avoid triggering
 
                         /* Let's ignore autofs mounts.  If they aren't
                          * triggered yet, we want to avoid triggering