Changeset 58763

Timestamp:

07/18/2024 06:02:17 PM (2 years ago)

Author:

jorbin

Message:

General: Provide _is_utf8_charset() in compat.php for early use

#61182 introduced is_utf8_charset() as a way of standardizing checks for charset slugs referring to UTF-8. This is called by _mb_strlen() inside of compat.php, but is_utf8_charset() is defined in functions.php, which isn't loaded early on. Code calling mb_strlen() early on before functions.php loads in hosts without the multibyte extension therefore may crash.

Props dmsnell, jonsurrell, joemcgill, jorbin.
Fixes #61681.

Location:

trunk/src/wp-includes

Files:

• compat.php (modified) (3 diffs)
• functions.php (modified) (2 diffs)

trunk/src/wp-includes/compat.php

@@ -39 +39 @@
 
         return $utf8_pcre;
+}
+
+/**
+ * Indicates if a given slug for a character set represents the UTF-8 text encoding.
+ *
+ * A charset is considered to represent UTF-8 if it is a case-insensitive match
+ * of "UTF-8" with or without the hyphen.
+ *
+ * Example:
+ *
+ *     true  === _is_utf8_charset( 'UTF-8' );
+ *     true  === _is_utf8_charset( 'utf8' );
+ *     false === _is_utf8_charset( 'latin1' );
+ *     false === _is_utf8_charset( 'UTF 8' );
+ *
+ *     // Only strings match.
+ *     false === _is_utf8_charset( [ 'charset' => 'utf-8' ] );
+ *
+ * `is_utf8_charset` should be used outside of this file.
+ *
+ * @ignore
+ * @since 6.6.1
+ *
+ * @param string $charset_slug Slug representing a text character encoding, or "charset".
+ *                             E.g. "UTF-8", "Windows-1252", "ISO-8859-1", "SJIS".
+ *
+ * @return bool Whether the slug represents the UTF-8 encoding.
+ */
+function _is_utf8_charset( $charset_slug ) {
+        if ( ! is_string( $charset_slug ) ) {
+                return false;
+        }
+
+        return (
+                0 === strcasecmp( 'UTF-8', $charset_slug ) ||
+                0 === strcasecmp( 'UTF8', $charset_slug )
+        );
 }
 
@@ -92 +129 @@
          * charset just use built-in substr().
          */
-        if ( ! is_utf8_charset( $encoding ) ) {
+        if ( ! _is_utf8_charset( $encoding ) ) {
                 return is_null( $length ) ? substr( $str, $start ) : substr( $str, $start, $length );
         }
@@ -177 +214 @@
          * just use built-in strlen().
          */
-        if ( ! is_utf8_charset( $encoding ) ) {
+        if ( ! _is_utf8_charset( $encoding ) ) {
                 return strlen( $str );
         }

trunk/src/wp-includes/functions.php

@@ -7497 +7497 @@
  *
  * @since 6.6.0
+ * @since 6.6.1 A wrapper for _is_utf8_charset
+ *
+ * @see _is_utf8_charset
  *
  * @param string|null $blog_charset Optional. Slug representing a text character encoding, or "charset".
@@ -7504 +7507 @@
  */
 function is_utf8_charset( $blog_charset = null ) {
-        $charset_to_examine = $blog_charset ?? get_option( 'blog_charset' );
-
-        /*
-         * Only valid string values count: the absence of a charset
-         * does not imply any charset, let alone UTF-8.
-         */
-        if ( ! is_string( $charset_to_examine ) ) {
-                return false;
-        }
-
-        return (
-                0 === strcasecmp( 'UTF-8', $charset_to_examine ) ||
-                0 === strcasecmp( 'UTF8', $charset_to_examine )
-        );
+        return _is_utf8_charset( $blog_charset ?? get_option( 'blog_charset' ) );
 }