stream: check fopen() mode ahead of time

And change the signature of php_stream_parse_fopen_modes() to not require an out param as the failure can simply be communicated via -1 which is not a valid open flag mode.

Author: Girgias

UPGRADING.INTERNALS

@@ -136,6 +136,12 @@ PHP 8.6 INTERNALS UPGRADE NOTES
   . Added zend_compile_ast().
   . Added zend_check_type_ex().
   . Added zend_create_partial_closure().
+  . The php_stream_parse_fopen_modes() function was changed from the following
+    PHPAPI int php_stream_parse_fopen_modes(const char *mode, int *open_flags);
+    to
+    PHPAPI int php_stream_parse_fopen_modes(const char *mode);
+    Instead of returning SUCCESS or FAILURE it now returns the open flags or -1
+    on failure.
 
 ========================
 2. Build system changes

ext/bz2/tests/002.phpt

@@ -27,18 +27,18 @@ var_dump(bzopen($fp, "r"));
 $fp = fopen("bz_open_002.txt", "wb");
 var_dump(bzopen($fp, "w"));
 
-$fp = fopen("bz_open_002.txt", "br");
 try {
+	$fp = fopen("bz_open_002.txt", "br");
     var_dump(bzopen($fp, "r"));
-} catch (\TypeError $e) {
-    echo $e->getMessage() . \PHP_EOL;
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
 }
 
-$fp = fopen("bz_open_002.txt", "br");
 try {
+	$fp = fopen("bz_open_002.txt", "br");
     var_dump(bzopen($fp, "w"));
-} catch (\TypeError $e) {
-    echo $e->getMessage() . \PHP_EOL;
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
 }
 
 $fp = fopen("bz_open_002.txt", "r");
@@ -89,12 +89,8 @@ Warning: bzopen(): Cannot read from a stream opened in write only mode in %s on
 bool(false)
 resource(%d) of type (stream)
 resource(%d) of type (stream)
-
-Warning: fopen(bz_open_002.txt): Failed to open stream: `br' is not a valid mode for fopen in %s on line %d
-bzopen(): Argument #1 ($file) must be of type string or file-resource, false given
-
-Warning: fopen(bz_open_002.txt): Failed to open stream: `br' is not a valid mode for fopen in %s on line %d
-bzopen(): Argument #1 ($file) must be of type string or file-resource, false given
+ValueError: fopen(): Argument #2 ($mode) must be a valid mode
+ValueError: fopen(): Argument #2 ($mode) must be a valid mode
 
 Warning: bzopen(): cannot write to a stream opened in read only mode in %s on line %d
 bool(false)

ext/standard/file.c

@@ -747,6 +747,12 @@ PHP_FUNCTION(fopen)
 		Z_PARAM_RESOURCE_OR_NULL(zcontext)
 	ZEND_PARSE_PARAMETERS_END();
 
+	int open_flags = php_stream_parse_fopen_modes(mode);
+	if (UNEXPECTED(open_flags == -1)) {
+		zend_argument_value_error(2, "must be a valid mode");
+		RETURN_THROWS();
+	}
+
 	php_stream_error_operation_begin();
 	context = php_stream_context_from_zval(zcontext, 0);
 

ext/standard/tests/file/bug76735.phpt

@@ -2,7 +2,11 @@
 Bug #76735 (Incorrect message in fopen on invalid mode)
 --FILE--
 <?php
-fopen(__FILE__, 'Q');
+try {
+	fopen(__FILE__, 'Q');
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
 ?>
---EXPECTF--
-Warning: fopen(%s): Failed to open stream: `Q' is not a valid mode for fopen in %s on line %d
+--EXPECT--
+ValueError: fopen(): Argument #2 ($mode) must be a valid mode

main/streams/php_stream_plain_wrapper.h

@@ -49,6 +49,6 @@ PHPAPI FILE * _php_stream_open_wrapper_as_file(char * path, char * mode, int opt
 #define php_stream_open_wrapper_as_file(path, mode, options, opened_path) _php_stream_open_wrapper_as_file((path), (mode), (options), (opened_path) STREAMS_CC)
 
 /* parse standard "fopen" modes into open() flags */
-PHPAPI int php_stream_parse_fopen_modes(const char *mode, int *open_flags);
+PHPAPI int php_stream_parse_fopen_modes(const char *mode);
 
 END_EXTERN_C()

main/streams/plain_wrapper.c

@@ -69,8 +69,8 @@ extern int php_get_gid_by_name(const char *name, gid_t *gid);
 # endif
 #endif
 
-/* parse standard "fopen" modes into open() flags */
-PHPAPI int php_stream_parse_fopen_modes(const char *mode, int *open_flags)
+/* parse standard "fopen" modes into open() flags. Returns -1 on failure, open flags on success. */
+PHPAPI int php_stream_parse_fopen_modes(const char *mode)
 {
 	int flags;
 
@@ -92,7 +92,7 @@ PHPAPI int php_stream_parse_fopen_modes(const char *mode, int *open_flags)
 			break;
 		default:
 			/* unknown mode */
-			return FAILURE;
+			return -1;
 	}
 
 	if (strchr(mode, '+')) {
@@ -123,8 +123,7 @@ PHPAPI int php_stream_parse_fopen_modes(const char *mode, int *open_flags)
 	}
 #endif
 
-	*open_flags = flags;
-	return SUCCESS;
+	return flags;
 }
 
 
@@ -1166,15 +1165,15 @@ static php_stream *php_plain_files_dir_opener(php_stream_wrapper *wrapper, const
 PHPAPI php_stream *_php_stream_fopen(const char *filename, const char *mode, zend_string **opened_path, int options STREAMS_DC)
 {
 	char realpath[MAXPATHLEN];
-	int open_flags;
 	int fd;
 	php_stream *ret;
 	int persistent = options & STREAM_OPEN_PERSISTENT;
 	char *persistent_id = NULL;
 
-	if (FAILURE == php_stream_parse_fopen_modes(mode, &open_flags)) {
+	int open_flags = php_stream_parse_fopen_modes(mode);
+	if (UNEXPECTED(open_flags == -1)) {
 		php_stream_wrapper_log_warn(&php_plain_files_wrapper, NULL, options,
-				InvalidMode, "`%s' is not a valid mode for fopen", mode);
+				InvalidMode, "\"%s\" is not a valid mode for fopen", mode);
 		return NULL;
 	}
 

main/streams/streams.c

@@ -1611,13 +1611,15 @@ PHPAPI zend_result _php_stream_copy_to_stream_ex(php_stream *src, php_stream *de
 			src->writepos == src->readpos) {
 		/* both php_stream instances are backed by a file descriptor, are not filtered and the
 		 * read buffer is empty: we can use copy_file_range() */
-		int src_fd, dest_fd, dest_open_flags = 0;
+		int src_fd, dest_fd = 0;
+
+		/* get dest open flags to check if the stream is open in append mode */
+		int dest_open_flags = php_stream_parse_fopen_modes(dest->mode);
+		ZEND_ASSERT(dest_open_flags > -1 && "Must be able to parse stream open flag mode if we have a valid stream");
 
 		/* copy_file_range does not work with O_APPEND */
 		if (php_stream_cast(src, PHP_STREAM_AS_FD, (void*)&src_fd, 0) == SUCCESS &&
 				php_stream_cast(dest, PHP_STREAM_AS_FD, (void*)&dest_fd, 0) == SUCCESS &&
-				/* get dest open flags to check if the stream is open in append mode */
-				php_stream_parse_fopen_modes(dest->mode, &dest_open_flags) == SUCCESS &&
 				!(dest_open_flags & O_APPEND)) {
 
 			/* clamp to INT_MAX to avoid EOVERFLOW */

win32/ioutil.c

@@ -691,7 +691,7 @@ PW32IO FILE *php_win32_ioutil_fopen_w(const wchar_t *path, const wchar_t *mode)
 {/*{{{*/
 	FILE *ret;
 	char modea[16] = {0};
-	int err = 0, fd, flags, i = 0;
+	int err = 0, fd, i = 0;
 
 	PHP_WIN32_IOUTIL_CHECK_PATH_W(path, NULL, 0)
 
@@ -700,7 +700,9 @@ PW32IO FILE *php_win32_ioutil_fopen_w(const wchar_t *path, const wchar_t *mode)
 		modea[i] = (char)mode[i];
 		i++;
 	}
-	if (SUCCESS != php_stream_parse_fopen_modes(modea, &flags)) {
+
+	int flags = php_stream_parse_fopen_modes(modea);
+	if (UNEXPECTED(flags == -1)) {
 		SET_ERRNO_FROM_WIN32_CODE(ERROR_INVALID_PARAMETER);
 		return NULL;
 	}