Implement __idna_to_unicode_lzlz. Split __idna_to_ascii_lz in two parts so that loading can be shared with the new function.

libidn/idn-stub.c

@@ -33,6 +33,77 @@
 static void *h;
 
 
+static int (*to_ascii_lz) (const char *input, char **output, int flags);
+static int (*to_unicode_lzlz) (const char *input, char **output, int flags);
+
+
+static void
+load_dso (void)
+{
+  /* Lock protecting the DSO loading.  */
+  __libc_lock_define_initialized (static, lock);
+
+  __libc_lock_lock (lock);
+
+  /* Retest in case some other thread arrived here at the same time.  */
+  if (h == NULL)
+    {
+      h = __libc_dlopen (LIBCIDN_SO);
+
+      if (h == NULL)
+	h = (void *) 1l;
+      else
+	{
+	  /* Get the function we are interested in.  */
+	  to_ascii_lz = __libc_dlsym (h, "idna_to_ascii_lz");
+	  to_unicode_lzlz = __libc_dlsym (h, "idna_to_unicode_lzlz");
+	  if (to_ascii_lz == NULL || to_unicode_lzlz == NULL)
+	    {
+	      __libc_dlclose (h);
+	      h = (void *) 1l;
+	    }
+	}
+    }
+
+  __libc_lock_unlock (lock);
+}
+
+
+/* Stub to dlopen libcidn.so and invoke the real idna_to_ascii_lz, or
+   return IDNA_DLOPEN_ERROR on failure.  */
+int
+__idna_to_unicode_lzlz (const char *input, char **output, int flags)
+{
+  /* If the input string contains no "xn--" prefix for a component of
+     the name we can pass it up right away.  */
+  const char *cp = input;
+  while (*cp != '\0')
+    {
+      if (strncmp (cp, IDNA_ACE_PREFIX, strlen (IDNA_ACE_PREFIX)) == 0)
+	break;
+
+      /* On to the next part of the name.  */
+      cp = strchrnul (cp, '.');
+      if (*cp == '.')
+	++cp;
+    }
+
+  if (*cp == '\0')
+    {
+      *output = (char *) input;
+      return IDNA_SUCCESS;
+    }
+
+  if (h == NULL)
+    load_dso ();
+
+  if (h == (void *) 1l)
+    return IDNA_DLOPEN_ERROR;
+
+  return to_unicode_lzlz (input, output, flags);
+}
+
+
 /* Stub to dlopen libcidn.so and invoke the real idna_to_ascii_lz, or
    return IDNA_DLOPEN_ERROR on failure.  */
 int
@@ -47,39 +118,12 @@ __idna_to_ascii_lz (const char *input, char **output, int flags)
 
   if (*cp == '\0')
     {
-      *output = strdup (input);
+      *output = (char *) input;
-      return *output == NULL ? IDNA_MALLOC_ERROR : IDNA_SUCCESS;
+      return IDNA_SUCCESS;
     }
 
-  static int (*to_ascii_lz) (const char *input, char **output, int flags);
-
   if (h == NULL)
-    {
+    load_dso ();
-      __libc_lock_define_initialized (static, lock);
-
-      __libc_lock_lock (lock);
-
-      /* Retest in case some other thread arrived here at the same time.  */
-      if (h == NULL)
-	{
-	  h = __libc_dlopen (LIBCIDN_SO);
-
-	  if (h == NULL)
-	    h = (void *) 1l;
-	  else
-	    {
-	      /* Get the function we are interested in.  */
-	      to_ascii_lz = __libc_dlsym (h, "idna_to_ascii_lz");
-	      if (to_ascii_lz == NULL)
-		{
-		  __libc_dlclose (h);
-		  h = (void *) 1l;
-		}
-	    }
-	}
-
-      __libc_lock_unlock (lock);
-    }
 
   if (h == (void *) 1l)
     return IDNA_DLOPEN_ERROR;