Fix #53251: bindtextdomain with null dir doesn't return old value

Apparently, users expect `bindtextdomain` and `bind_textdomain_codeset`
with `null` as second argument to work like their C counterparts,
namely to return the previously set value.  Thus, we support that.

Closes GH-6631.

Author: cmb69

NEWS

@@ -2,6 +2,10 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? 2021, PHP 8.0.3
 
+- Gettext:
+  . Fixed bug #53251 (bindtextdomain with null dir doesn't return old value).
+    (cmb)
+
 - Opcache:
   . Fixed bug #80634 (write_property handler of internal classes is skipped on
     preloaded JITted code). (Dmitry)

ext/gettext/gettext.c

@@ -163,11 +163,11 @@ PHP_FUNCTION(dcgettext)
 /* {{{ Bind to the text domain domain_name, looking for translations in dir. Returns the current domain */
 PHP_FUNCTION(bindtextdomain)
 {
-	char *domain, *dir;
+	char *domain, *dir = NULL;
 	size_t domain_len, dir_len;
 	char *retval, dir_name[MAXPATHLEN];
 
-	if (zend_parse_parameters(ZEND_NUM_ARGS(), "ss", &domain, &domain_len, &dir, &dir_len) == FAILURE) {
+	if (zend_parse_parameters(ZEND_NUM_ARGS(), "ss!", &domain, &domain_len, &dir, &dir_len) == FAILURE) {
 		RETURN_THROWS();
 	}
 
@@ -178,6 +178,10 @@ PHP_FUNCTION(bindtextdomain)
 		RETURN_THROWS();
 	}
 
+	if (dir == NULL) {
+		RETURN_STRING(bindtextdomain(domain, NULL));
+	}
+
 	if (dir[0] != '\0' && strcmp(dir, "0")) {
 		if (!VCWD_REALPATH(dir, dir_name)) {
 			RETURN_FALSE;
@@ -272,10 +276,10 @@ PHP_FUNCTION(dcngettext)
 /* {{{ Specify the character encoding in which the messages from the DOMAIN message catalog will be returned. */
 PHP_FUNCTION(bind_textdomain_codeset)
 {
-	char *domain, *codeset, *retval = NULL;
+	char *domain, *codeset = NULL, *retval = NULL;
 	size_t domain_len, codeset_len;
 
-	if (zend_parse_parameters(ZEND_NUM_ARGS(), "ss", &domain, &domain_len, &codeset, &codeset_len) == FAILURE) {
+	if (zend_parse_parameters(ZEND_NUM_ARGS(), "ss!", &domain, &domain_len, &codeset, &codeset_len) == FAILURE) {
 		RETURN_THROWS();
 	}
 

ext/gettext/gettext.stub.php

@@ -13,7 +13,7 @@ function dgettext(string $domain, string $message): string {}
 
 function dcgettext(string $domain, string $message, int $category): string {}
 
-function bindtextdomain(string $domain, string $directory): string|false {}
+function bindtextdomain(string $domain, ?string $directory): string|false {}
 
 #ifdef HAVE_NGETTEXT
 function ngettext(string $singular, string $plural, int $count): string {}
@@ -28,5 +28,5 @@ function dcngettext(string $domain, string $singular, string $plural, int $count
 #endif
 
 #ifdef HAVE_BIND_TEXTDOMAIN_CODESET
-function bind_textdomain_codeset(string $domain, string $codeset): string|false {}
+function bind_textdomain_codeset(string $domain, ?string $codeset): string|false {}
 #endif

ext/gettext/gettext_arginfo.h

@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 7d0fe93cb15576756edc5aad71deadae67046690 */
+ * Stub hash: 3fbd90b87dfcbc5a1a0a2aea8d0cc45516e221ce */
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_textdomain, 0, 1, IS_STRING, 0)
 	ZEND_ARG_TYPE_INFO(0, domain, IS_STRING, 1)
@@ -24,7 +24,7 @@ ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_MASK_EX(arginfo_bindtextdomain, 0, 2, MAY_BE_STRING|MAY_BE_FALSE)
 	ZEND_ARG_TYPE_INFO(0, domain, IS_STRING, 0)
-	ZEND_ARG_TYPE_INFO(0, directory, IS_STRING, 0)
+	ZEND_ARG_TYPE_INFO(0, directory, IS_STRING, 1)
 ZEND_END_ARG_INFO()
 
 #if defined(HAVE_NGETTEXT)
@@ -57,7 +57,7 @@ ZEND_END_ARG_INFO()
 #if defined(HAVE_BIND_TEXTDOMAIN_CODESET)
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_MASK_EX(arginfo_bind_textdomain_codeset, 0, 2, MAY_BE_STRING|MAY_BE_FALSE)
 	ZEND_ARG_TYPE_INFO(0, domain, IS_STRING, 0)
-	ZEND_ARG_TYPE_INFO(0, codeset, IS_STRING, 0)
+	ZEND_ARG_TYPE_INFO(0, codeset, IS_STRING, 1)
 ZEND_END_ARG_INFO()
 #endif
 

ext/gettext/tests/bug53251.phpt

@@ -0,0 +1,23 @@
+--TEST--
+Bug #53251 (bindtextdomain with null dir doesn't return old value)
+--SKIPIF--
+<?php
+if (!extension_loaded('gettext')) die('skip gettext extension not available');
+?>
+--FILE--
+<?php
+var_dump(is_string(bindtextdomain('foo', null)));
+$dir = bindtextdomain('foo', '.');
+var_dump(bindtextdomain('foo', null) === $dir);
+
+var_dump(bind_textdomain_codeset('foo', null));
+var_dump(bind_textdomain_codeset('foo', 'UTF-8'));
+var_dump(bind_textdomain_codeset('foo', null));
+
+?>
+--EXPECT--
+bool(true)
+bool(true)
+bool(false)
+string(5) "UTF-8"
+string(5) "UTF-8"