Changeset 38015 for trunk/src/wp-includes/functions.php

Timestamp:

07/08/2016 02:36:37 PM (9 years ago)

Author:

ocean90

Message:

Bootstrap: Enhance core's memory limit handling.

• Don't lower memory limit if the current limit is greater than WP_MAX_MEMORY_LIMIT.
• Set WP_MEMORY_LIMIT and WP_MAX_MEMORY_LIMIT to current limit if the memory_limit setting can't be changed at runtime.
• Use wp_convert_hr_to_bytes() when parsing the value of the memory_limit setting because it can be a shorthand or an integer value.
• Introduce wp_raise_memory_limit( $context ) to raise the PHP memory limit for memory intensive processes. This DRYs up some logic and includes the existing admin_memory_limit and image_memory_limit filters. The function can also be used for custom contexts, the {$context}_memory_limit filter allows to customize the limit.
• Introduce wp_is_ini_value_changeable( $setting ) to determine whether a PHP ini value is changeable at runtime.
• Remove a function_exists( 'memory_get_usage' ) check. Since PHP 5.2.1 support for memory limit is always enabled.

Related commits: [38011-38013]

Props jrf, A5hleyRich, swissspidy, ocean90.
Fixes #32075.

File:

• trunk/src/wp-includes/functions.php (modified) (1 diff)

trunk/src/wp-includes/functions.php

@@ -5380 +5380 @@
     return false;
 }
+
+/**
+ * Attempts to raise the PHP memory limit for memory intensive processes.
+ *
+ * Only allows raising the existing limit and prevents lowering it.
+ *
+ * @since 4.6.0
+ *
+ * @param string $context  Context in which the function is called.
+ *                         Either 'admin', 'image' or an arbitrary other context.
+ *                         Defaults to 'admin'.
+ *                         If an arbitrary context is passed, the similarly arbitrary
+ *                         "{$context}_memory_limit" filter will be invoked.
+ * @return bool|int|string The limit that was set or false on failure.
+ */
+function wp_raise_memory_limit( $context = 'admin' ) {
+    // Exit early if the limit cannot be changed.
+    if ( false === wp_is_ini_value_changeable( 'memory_limit' ) ) {
+        return false;
+    }
+
+    $current_limit     = @ini_get( 'memory_limit' );
+    $current_limit_int = wp_convert_hr_to_bytes( $current_limit );
+
+    if ( -1 === $current_limit_int ) {
+        return false;
+    }
+
+    $wp_max_limit     = WP_MAX_MEMORY_LIMIT;
+    $wp_max_limit_int = wp_convert_hr_to_bytes( $wp_max_limit );
+    $filtered_limit   = $wp_max_limit;
+
+    switch ( $context ) {
+        case 'admin':
+            /**
+             * Filters the maximum memory limit available for administration screens.
+             *
+             * This only applies to administrators, who may require more memory for tasks like updates.
+             * Memory limits when processing images (uploaded or edited by users of any role) are
+             * handled separately.
+             *
+             * The WP_MAX_MEMORY_LIMIT constant specifically defines the maximum memory limit available
+             * when in the administration back end. The default is 256M (256 megabytes
+             * of memory) or the original `memory_limit` php.ini value if this is higher.
+             *
+             * @since 3.0.0
+             * @since 4.6.0 The default takes the original `memory_limit` into account.
+             *
+             * @param int|string $filtered_limit The maximum WordPress memory limit.
+             *                                   Accepts an integer (bytes), or a shorthand string
+             *                                   notation, such as '256M'.
+             */
+            $filtered_limit = apply_filters( 'admin_memory_limit', $filtered_limit );
+            break;
+
+        case 'image':
+            /**
+             * Filters the memory limit allocated for image manipulation.
+             *
+             * @since 3.5.0
+             * @since 4.6.0 The default takes the original `memory_limit` into account.
+             *
+             * @param int|string $filtered_limit Maximum memory limit to allocate for images.
+             *                                   Default WP_MAX_MEMORY_LIMIT or the original
+             *                                   php.ini memory_limit, whichever is higher.
+             *                                   Accepts an integer (bytes), or a shorthand string
+             *                                   notation, such as '256M'.
+             */
+            $filtered_limit = apply_filters( 'image_memory_limit', $filtered_limit );
+            break;
+
+        default:
+            /**
+             * Filters the memory limit allocated for arbitrary contexts.
+             *
+             * The dynamic portion of the hook name, `$context`, refers to an arbitrary
+             * context passed on calling the function. This allows for plugins to define
+             * their own contexts for raising the memory limit.
+             *
+             * @since 4.6.0
+             *
+             * @param int|string $filtered_limit Maximum memory limit to allocate for images.
+             *                                   Default 256M or the original php.ini memory_limit,
+             *                                   whichever is higher.
+             *                                   Accepts an integer (bytes), or a shorthand string
+             *                                   notation, such as '256M'.
+             */
+            $filtered_limit = apply_filters( "{$context}_memory_limit", $filtered_limit );
+            break;
+    }
+
+    $filtered_limit_int = wp_convert_hr_to_bytes( $filtered_limit );
+
+    if ( -1 === $filtered_limit_int || ( $filtered_limit_int > $wp_max_limit_int && $filtered_limit_int > $current_limit_int ) ) {
+        if ( false !== @ini_set( 'memory_limit', $filtered_limit ) ) {
+            return $filtered_limit;
+        } else {
+            return false;
+        }
+    } elseif ( -1 === $wp_max_limit_int || $wp_max_limit_int > $current_limit_int ) {
+        if ( false !== @ini_set( 'memory_limit', $wp_max_limit ) ) {
+            return $wp_max_limit;
+        } else {
+            return false;
+        }
+    }
+
+    return false;
+}