lib/core: Add ostree_validate_remote_name() for remote names

There are a few places in the code where ad-hoc validation was being
performed. Might as well formalise it a bit more.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

Closes: #948
Approved by: cgwalters

src/libostree/libostree-devel.sym

@@ -19,7 +19,9 @@
 
 /* Add new symbols here.  Release commits should copy this section into -released.sym. */
 LIBOSTREE_2017.8 {
-};
+global:
+  ostree_validate_remote_name;
+} LIBOSTREE_2017.7;
 
 /* Stub section for the stable release *after* this development one; don't
  * edit this other than to update the last number.  This is just a copy/paste

src/libostree/ostree-core.c

@@ -101,6 +101,7 @@ ostree_validate_checksum_string (const char *sha256,
 
 #define OSTREE_REF_FRAGMENT_REGEXP "[-._\\w\\d]+"
 #define OSTREE_REF_REGEXP "(?:" OSTREE_REF_FRAGMENT_REGEXP "/)*" OSTREE_REF_FRAGMENT_REGEXP
+#define OSTREE_REMOTE_NAME_REGEXP OSTREE_REF_FRAGMENT_REGEXP
 
 /**
  * ostree_parse_refspec:
@@ -125,7 +126,7 @@ ostree_parse_refspec (const char   *refspec,
   static gsize regex_initialized;
   if (g_once_init_enter (&regex_initialized))
     {
-      regex = g_regex_new ("^(" OSTREE_REF_FRAGMENT_REGEXP ":)?(" OSTREE_REF_REGEXP ")$", 0, 0, NULL);
+      regex = g_regex_new ("^(" OSTREE_REMOTE_NAME_REGEXP ":)?(" OSTREE_REF_REGEXP ")$", 0, 0, NULL);
       g_assert (regex);
       g_once_init_leave (&regex_initialized, 1);
     }
@@ -180,6 +181,35 @@ ostree_validate_rev (const char *rev,
   return TRUE;
 }
 
+/**
+ * ostree_validate_remote_name:
+ * @remote_name: A remote name
+ * @error: Error
+ *
+ * Returns: %TRUE if @remote_name is a valid remote name
+ * Since: 2017.7
+ */
+gboolean
+ostree_validate_remote_name (const char  *remote_name,
+                             GError     **error)
+{
+  g_autoptr(GMatchInfo) match = NULL;
+
+  static gsize regex_initialized;
+  static GRegex *regex;
+  if (g_once_init_enter (&regex_initialized))
+    {
+      regex = g_regex_new ("^" OSTREE_REMOTE_NAME_REGEXP "$", 0, 0, NULL);
+      g_assert (regex);
+      g_once_init_leave (&regex_initialized, 1);
+    }
+
+  if (!g_regex_match (regex, remote_name, 0, &match))
+    return glnx_throw (error, "Invalid remote name %s", remote_name);
+
+  return TRUE;
+}
+
 GVariant *
 _ostree_file_header_new (GFileInfo         *file_info,
                          GVariant          *xattrs)

src/libostree/ostree-core.h

@@ -242,6 +242,9 @@ int ostree_cmp_checksum_bytes (const guchar *a, const guchar *b);
 _OSTREE_PUBLIC
 gboolean ostree_validate_rev (const char *rev, GError **error);
 
+_OSTREE_PUBLIC
+gboolean ostree_validate_remote_name (const char *remote_name, GError **error);
+
 _OSTREE_PUBLIC
 gboolean ostree_parse_refspec (const char *refspec,
                                char      **out_remote,

src/libostree/ostree-repo.c

@@ -876,8 +876,8 @@ impl_repo_remote_add (OstreeRepo     *self,
   g_return_val_if_fail (url != NULL, FALSE);
   g_return_val_if_fail (options == NULL || g_variant_is_of_type (options, G_VARIANT_TYPE ("a{sv}")), FALSE);
 
-  if (strchr (name, '/') != NULL)
-    return glnx_throw (error, "Invalid character '/' in remote name: %s", name);
+  if (!ostree_validate_remote_name (name, error))
+    return FALSE;
 
   g_autoptr(OstreeRemote) remote = _ostree_repo_get_remote (self, name, NULL);
   if (remote != NULL && if_not_exists)
@@ -1005,8 +1005,8 @@ impl_repo_remote_delete (OstreeRepo     *self,
 {
   g_return_val_if_fail (name != NULL, FALSE);
 
-  if (strchr (name, '/') != NULL)
-    return glnx_throw (error, "Invalid character '/' in remote name: %s", name);
+  if (!ostree_validate_remote_name (name, error))
+    return FALSE;
 
   g_autoptr(OstreeRemote) remote = NULL;
   if (if_exists)