Rename path_prefix to path_namespace and disallow trailing '/'

Also disallow having both path and path_namespace in the same match rule
(it wouldn't make sense, path is more specific than path_namespace).

As per IRC discussion with davidz and wjt.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=34870

3 files changed, 64 insertions, 119 deletions

diff --git a/bus/signals.c b/bus/signals.c
index 59133344..d0e72bf6 100644
--- a/bus/signals.c
+++ b/bus/signals.c
@@ -41,7 +41,6 @@ struct BusMatchRule
   char *sender;
   char *destination;
   char *path;
-  char *path_prefix;
 
   unsigned int *arg_lens;
   char **args;
@@ -95,7 +94,6 @@ bus_match_rule_unref (BusMatchRule *rule)
       dbus_free (rule->sender);
       dbus_free (rule->destination);
       dbus_free (rule->path);
-      dbus_free (rule->path_prefix);
       dbus_free (rule->arg_lens);
 
       /* can't use dbus_free_string_array() since there
@@ -208,7 +206,7 @@ match_rule_to_string (BusMatchRule *rule)
         goto nomem;
     }
 
-  if (rule->flags & BUS_MATCH_PATH_PREFIX)
+  if (rule->flags & BUS_MATCH_PATH_NAMESPACE)
     {
       if (_dbus_string_get_length (&str) > 0)
         {
@@ -216,7 +214,7 @@ match_rule_to_string (BusMatchRule *rule)
             goto nomem;
         }
 
-      if (!_dbus_string_append_printf (&str, "path_prefix='%s'", rule->path_prefix))
+      if (!_dbus_string_append_printf (&str, "path_namespace='%s'", rule->path))
         goto nomem;
     }
 
@@ -385,7 +383,8 @@ bus_match_rule_set_destination (BusMatchRule *rule,
 
 dbus_bool_t
 bus_match_rule_set_path (BusMatchRule *rule,
-                         const char   *path)
+                         const char   *path,
+                         dbus_bool_t   is_namespace)
 {
   char *new;
 
@@ -395,28 +394,15 @@ bus_match_rule_set_path (BusMatchRule *rule,
   if (new == NULL)
     return FALSE;
 
-  rule->flags |= BUS_MATCH_PATH;
-  dbus_free (rule->path);
-  rule->path = new;
-
-  return TRUE;
-}
-
-dbus_bool_t
-bus_match_rule_set_path_prefix (BusMatchRule *rule,
-                                const char   *path_prefix)
-{
-  char *new;
-
-  _dbus_assert (path_prefix != NULL);
+  rule->flags &= ~(BUS_MATCH_PATH|BUS_MATCH_PATH_NAMESPACE);
 
-  new = _dbus_strdup (path_prefix);
-  if (new == NULL)
-    return FALSE;
+  if (is_namespace)
+    rule->flags |= BUS_MATCH_PATH_NAMESPACE;
+  else
+    rule->flags |= BUS_MATCH_PATH;
 
-  rule->flags |= BUS_MATCH_PATH_PREFIX;
-  dbus_free (rule->path_prefix);
-  rule->path_prefix = new;
+  dbus_free (rule->path);
+  rule->path = new;
 
   return TRUE;
 }
@@ -1029,12 +1015,15 @@ bus_match_rule_parse (DBusConnection   *matches_go_to,
               goto failed;
             }
         }
-      else if (strcmp (key, "path") == 0)
+      else if (strcmp (key, "path") == 0 ||
+          strcmp (key, "path_namespace") == 0)
         {
-          if (rule->flags & BUS_MATCH_PATH)
+          dbus_bool_t is_namespace = (strcmp (key, "path_namespace") == 0);
+
+          if (rule->flags & (BUS_MATCH_PATH | BUS_MATCH_PATH_NAMESPACE))
             {
               dbus_set_error (error, DBUS_ERROR_MATCH_RULE_INVALID,
-                              "Key %s specified twice in match rule\n", key);
+                              "path or path_namespace specified twice in match rule\n");
               goto failed;
             }
 
@@ -1045,35 +1034,7 @@ bus_match_rule_parse (DBusConnection   *matches_go_to,
               goto failed;
             }
 
-          if (!bus_match_rule_set_path (rule, value))
-            {
-              BUS_SET_OOM (error);
-              goto failed;
-            }
-        }
-      else if (strcmp (key, "path_prefix") == 0)
-        {
-          int path_prefix_len;
-
-          if (rule->flags & BUS_MATCH_PATH_PREFIX)
-            {
-              dbus_set_error (error, DBUS_ERROR_MATCH_RULE_INVALID,
-                              "Key %s specified twice in match rule\n", key);
-              goto failed;
-            }
-
-          path_prefix_len = len;
-          if (_dbus_string_ends_with_c_str (&tmp_str, "/"))
-            path_prefix_len--;
-
-          if (!_dbus_validate_path (&tmp_str, 0, path_prefix_len))
-            {
-              dbus_set_error (error, DBUS_ERROR_MATCH_RULE_INVALID,
-                              "Path prefix '%s' is invalid\n", value);
-              goto failed;
-            }
-
-          if (!bus_match_rule_set_path_prefix (rule, value))
+          if (!bus_match_rule_set_path (rule, value, is_namespace))
             {
               BUS_SET_OOM (error);
               goto failed;
@@ -1411,10 +1372,6 @@ match_rule_equal (BusMatchRule *a,
       strcmp (a->path, b->path) != 0)
     return FALSE;
 
-  if ((a->flags & BUS_MATCH_PATH_PREFIX) &&
-      strcmp (a->path_prefix, b->path_prefix) != 0)
-    return FALSE;
-  
   if ((a->flags & BUS_MATCH_INTERFACE) &&
       strcmp (a->interface, b->interface) != 0)
     return FALSE;
@@ -1798,29 +1755,28 @@ match_rule_matches (BusMatchRule    *rule,
         return FALSE;
     }
 
-  if (flags & BUS_MATCH_PATH_PREFIX)
+  if (flags & BUS_MATCH_PATH_NAMESPACE)
     {
       const char *path;
       int len;
 
-      _dbus_assert (rule->path_prefix != NULL);
+      _dbus_assert (rule->path != NULL);
 
       path = dbus_message_get_path (message);
       if (path == NULL)
         return FALSE;
 
-      if (!str_has_prefix (path, rule->path_prefix))
+      if (!str_has_prefix (path, rule->path))
         return FALSE;
 
-      len = strlen (rule->path_prefix);
+      len = strlen (rule->path);
 
       /* Check that the actual argument is within the expected
        * namespace, rather than just starting with that string,
-       * by checking that the matched prefix either ends in a '/',
-       * or is followed by a '/' or the end of the path.
+       * by checking that the matched prefix is followed by a '/'
+       * or the end of the path.
        */
-      if (rule->path_prefix[len - 1] != '/' &&
-          path[len] != '\0' && path[len] != '/')
+      if (path[len] != '\0' && path[len] != '/')
         return FALSE;
     }
 
@@ -2719,47 +2675,43 @@ test_path_matching (void)
 }
 
 static const char*
-path_prefix_should_match_message_1[] = {
-  "type='signal',path_prefix='/foo'",
-  "type='signal',path_prefix='/foo/'",
-  "type='signal',path_prefix='/foo/TheObjectManager'",
+path_namespace_should_match_message_1[] = {
+  "type='signal',path_namespace='/foo'",
+  "type='signal',path_namespace='/foo/TheObjectManager'",
   NULL
 };
 
 static const char*
-path_prefix_should_not_match_message_1[] = {
-  "type='signal',path_prefix='/bar'",
-  "type='signal',path_prefix='/bar/'",
-  "type='signal',path_prefix='/bar/TheObjectManager'",
+path_namespace_should_not_match_message_1[] = {
+  "type='signal',path_namespace='/bar'",
+  "type='signal',path_namespace='/bar/TheObjectManager'",
   NULL
 };
 
 static const char*
-path_prefix_should_match_message_2[] = {
-  "type='signal',path_prefix='/foo/TheObjectManager'",
-  "type='signal',path_prefix='/foo/TheObjectManager/'",
+path_namespace_should_match_message_2[] = {
+  "type='signal',path_namespace='/foo/TheObjectManager'",
   NULL
 };
 
 static const char*
-path_prefix_should_not_match_message_2[] = {
+path_namespace_should_not_match_message_2[] = {
   NULL
 };
 
 static const char*
-path_prefix_should_match_message_3[] = {
+path_namespace_should_match_message_3[] = {
   NULL
 };
 
 static const char*
-path_prefix_should_not_match_message_3[] = {
-  "type='signal',path_prefix='/foo/TheObjectManager'",
-  "type='signal',path_prefix='/foo/TheObjectManager/'",
+path_namespace_should_not_match_message_3[] = {
+  "type='signal',path_namespace='/foo/TheObjectManager'",
   NULL
 };
 
 static void
-test_matching_path_prefix (void)
+test_matching_path_namespace (void)
 {
   DBusMessage *message1;
   DBusMessage *message2;
@@ -2781,14 +2733,14 @@ test_matching_path_prefix (void)
     _dbus_assert_not_reached ("oom");
 
   check_matching (message1, 1,
-                  path_prefix_should_match_message_1,
-                  path_prefix_should_not_match_message_1);
+                  path_namespace_should_match_message_1,
+                  path_namespace_should_not_match_message_1);
   check_matching (message2, 2,
-                  path_prefix_should_match_message_2,
-                  path_prefix_should_not_match_message_2);
+                  path_namespace_should_match_message_2,
+                  path_namespace_should_not_match_message_2);
   check_matching (message3, 3,
-                  path_prefix_should_match_message_3,
-                  path_prefix_should_not_match_message_3);
+                  path_namespace_should_match_message_3,
+                  path_namespace_should_not_match_message_3);
 
   dbus_message_unref (message3);
   dbus_message_unref (message2);
@@ -2811,7 +2763,7 @@ bus_signals_test (const DBusString *test_data_dir)
   test_equality ();
   test_matching ();
   test_path_matching ();
-  test_matching_path_prefix ();
+  test_matching_path_namespace ();
 
   return TRUE;
 }
diff --git a/bus/signals.h b/bus/signals.h
index 0053bd5d..5b086f04 100644
--- a/bus/signals.h
+++ b/bus/signals.h
@@ -31,14 +31,14 @@
 
 typedef enum
 {
-  BUS_MATCH_MESSAGE_TYPE = 1 << 0,
-  BUS_MATCH_INTERFACE    = 1 << 1,
-  BUS_MATCH_MEMBER       = 1 << 2,
-  BUS_MATCH_SENDER       = 1 << 3,
-  BUS_MATCH_DESTINATION  = 1 << 4,
-  BUS_MATCH_PATH         = 1 << 5,
-  BUS_MATCH_ARGS         = 1 << 6,
-  BUS_MATCH_PATH_PREFIX  = 1 << 7
+  BUS_MATCH_MESSAGE_TYPE   = 1 << 0,
+  BUS_MATCH_INTERFACE      = 1 << 1,
+  BUS_MATCH_MEMBER         = 1 << 2,
+  BUS_MATCH_SENDER         = 1 << 3,
+  BUS_MATCH_DESTINATION    = 1 << 4,
+  BUS_MATCH_PATH           = 1 << 5,
+  BUS_MATCH_ARGS           = 1 << 6,
+  BUS_MATCH_PATH_NAMESPACE = 1 << 7
 } BusMatchFlags;
 
 BusMatchRule* bus_match_rule_new   (DBusConnection *matches_go_to);
@@ -56,9 +56,8 @@ dbus_bool_t bus_match_rule_set_sender       (BusMatchRule     *rule,
 dbus_bool_t bus_match_rule_set_destination  (BusMatchRule     *rule,
                                              const char       *destination);
 dbus_bool_t bus_match_rule_set_path         (BusMatchRule     *rule,
-                                             const char       *path);
-dbus_bool_t bus_match_rule_set_path_prefix  (BusMatchRule     *rule,
-                                             const char       *path_prefix);
+                                             const char       *path,
+                                             dbus_bool_t       is_namespace);
 dbus_bool_t bus_match_rule_set_arg          (BusMatchRule     *rule,
                                              int               arg,
                                              const DBusString *value,
diff --git a/doc/dbus-specification.xml b/doc/dbus-specification.xml
index 6b446dd1..bef98871 100644
--- a/doc/dbus-specification.xml
+++ b/doc/dbus-specification.xml
@@ -3722,22 +3722,19 @@
                   path match is path='/org/freedesktop/Hal/Manager'</entry>
                 </row>
                 <row>
-                  <entry><literal>path_prefix</literal></entry>
-                  <entry>An object path optionally ending in a slash</entry>
+                  <entry><literal>path_namespace</literal></entry>
+                  <entry>An object path</entry>
                   <entry>
                     <para>
                       Matches messages which are sent from or to an
-                      object for which the object path is a descendant of
-                      the given value. If the prefix ends with a slash, it
-                      matches all paths starting with that string;
-                      if it does not end with a slash, it matches either
-                      that exact path, or that path followed by one or
+                      object for which the object path is either the
+                      given value, or that value followed by one or
                       more path components.
                     </para>
 
                     <para>
                       For example,
-                      <literal>path_prefix='/com/example/foo'</literal>
+                      <literal>path_namespace='/com/example/foo'</literal>
                       would match signals sent by
                       <literal>/com/example/foo</literal>
                       or by
@@ -3747,14 +3744,11 @@
                     </para>
 
                     <para>
-                      However,
-                      <literal>path_prefix='/com/example/foo/'</literal>
-                      would still match signals sent by
-                      <literal>/com/example/foo/bar</literal>,
-                      but would not match signals sent by
-                      <literal>/com/example/foo</literal> or
-                      <literal>/com/example/foobar</literal>.
+                      Using both <literal>path</literal> and
+                      <literal>path_namespace</literal> in the same match
+                      rule is not allowed.
                     </para>
+
                     <para>
                       <emphasis>
                         This match key was added in version 0.16 of the