* These functions can be replaced via plugins. If plugins do not redefine these
* functions, then these will be used instead.
if ( ! function_exists( 'wp_set_current_user' ) ) :
* Changes the current user by ID or name.
* Set $id to null and specify a name if you do not know a user's ID.
* Some WordPress functionality is based on the current user and not based on
* the signed in user. Therefore, it opens the ability to edit and perform
* actions on users who aren't signed in.
* @global WP_User $current_user The current user object which holds the user data.
* @param string $name User's username
* @return WP_User Current user User object
function wp_set_current_user( $id, $name = '' ) {
// If `$id` matches the current user, there is nothing to do.
if ( isset( $current_user )
&& ( $current_user instanceof WP_User )
&& ( $id == $current_user->ID )
$current_user = new WP_User( $id, $name );
setup_userdata( $current_user->ID );
* Fires after the current user is set.
do_action( 'set_current_user' );
if ( ! function_exists( 'wp_get_current_user' ) ) :
* Retrieve the current user object.
* Will set the current user, if the current user is not set. The current user
* will be set to the logged-in person. If no user is logged-in, then it will
* set the current user to 0, which is invalid and won't have any permissions.
* @see _wp_get_current_user()
* @global WP_User $current_user Checks if the current user is set.
* @return WP_User Current WP_User instance.
function wp_get_current_user() {
return _wp_get_current_user();
if ( ! function_exists( 'get_userdata' ) ) :
* Retrieve user info by user ID.
* @param int $user_id User ID
* @return WP_User|false WP_User object on success, false on failure.
function get_userdata( $user_id ) {
return get_user_by( 'id', $user_id );
if ( ! function_exists( 'get_user_by' ) ) :
* Retrieve user info by a given field
* @since 4.4.0 Added 'ID' as an alias of 'id' for the `$field` parameter.
* @param string $field The field to retrieve the user with. id | ID | slug | email | login.
* @param int|string $value A value for $field. A user ID, slug, email address, or login name.
* @return WP_User|false WP_User object on success, false on failure.
function get_user_by( $field, $value ) {
$userdata = WP_User::get_data_by( $field, $value );
$user->init( $userdata );
if ( ! function_exists( 'cache_users' ) ) :
* Retrieve info for user lists to prevent multiple queries by get_userdata()
* @global wpdb $wpdb WordPress database abstraction object.
* @param array $user_ids User ID numbers list
function cache_users( $user_ids ) {
$clean = _get_non_cached_ids( $user_ids, 'users' );
$list = implode( ',', $clean );
$users = $wpdb->get_results( "SELECT * FROM $wpdb->users WHERE ID IN ($list)" );
foreach ( $users as $user ) {
update_user_caches( $user );
update_meta_cache( 'user', $ids );
if ( ! function_exists( 'wp_mail' ) ) :
* Sends an email, similar to PHP's mail function.
* A true return value does not automatically mean that the user received the
* email successfully. It just only means that the method used was able to
* process the request without any errors.
* The default content type is `text/plain` which does not allow using HTML.
* However, you can set the content type of the email by using the
* {@see 'wp_mail_content_type'} filter.
* The default charset is based on the charset used on the blog. The charset can
* be set using the {@see 'wp_mail_charset'} filter.
* @global PHPMailer\PHPMailer\PHPMailer $phpmailer
* @param string|string[] $to Array or comma-separated list of email addresses to send message.
* @param string $subject Email subject.
* @param string $message Message contents.
* @param string|string[] $headers Optional. Additional headers.
* @param string|string[] $attachments Optional. Paths to files to attach.
* @return bool Whether the email was sent successfully.
function wp_mail( $to, $subject, $message, $headers = '', $attachments = array() ) {
// Compact the input, apply the filters, and extract them back out.
* Filters the wp_mail() arguments.
* Array of the `wp_mail()` arguments.
* @type string|string[] $to Array or comma-separated list of email addresses to send message.
* @type string $subject Email subject.
* @type string $message Message contents.
* @type string|string[] $headers Additional headers.
* @type string|string[] $attachments Paths to files to attach.
$atts = apply_filters( 'wp_mail', compact( 'to', 'subject', 'message', 'headers', 'attachments' ) );
* Filters whether to preempt sending an email.
* Returning a non-null value will short-circuit {@see wp_mail()}, returning
* that value instead. A boolean return value should be used to indicate whether
* the email was successfully sent.
* @param null|bool $return Short-circuit return value.
* Array of the `wp_mail()` arguments.
* @type string|string[] $to Array or comma-separated list of email addresses to send message.
* @type string $subject Email subject.
* @type string $message Message contents.
* @type string|string[] $headers Additional headers.
* @type string|string[] $attachments Paths to files to attach.
$pre_wp_mail = apply_filters( 'pre_wp_mail', null, $atts );
if ( null !== $pre_wp_mail ) {
if ( isset( $atts['to'] ) ) {
if ( ! is_array( $to ) ) {
$to = explode( ',', $to );
if ( isset( $atts['subject'] ) ) {
$subject = $atts['subject'];
if ( isset( $atts['message'] ) ) {
$message = $atts['message'];
if ( isset( $atts['headers'] ) ) {
$headers = $atts['headers'];
if ( isset( $atts['attachments'] ) ) {
$attachments = $atts['attachments'];
if ( ! is_array( $attachments ) ) {
$attachments = explode( "\n", str_replace( "\r\n", "\n", $attachments ) );
// (Re)create it, if it's gone missing.
if ( ! ( $phpmailer instanceof PHPMailer\PHPMailer\PHPMailer ) ) {
require_once ABSPATH . WPINC . '/PHPMailer/PHPMailer.php';
require_once ABSPATH . WPINC . '/PHPMailer/SMTP.php';
require_once ABSPATH . WPINC . '/PHPMailer/Exception.php';
$phpmailer = new PHPMailer\PHPMailer\PHPMailer( true );
$phpmailer::$validator = static function ( $email ) {
return (bool) is_email( $email );
if ( empty( $headers ) ) {
if ( ! is_array( $headers ) ) {
// Explode the headers out, so this function can take
// both string headers and an array of headers.
$tempheaders = explode( "\n", str_replace( "\r\n", "\n", $headers ) );
// If it's actually got contents.
if ( ! empty( $tempheaders ) ) {
// Iterate through the raw headers.
foreach ( (array) $tempheaders as $header ) {
if ( strpos( $header, ':' ) === false ) {
if ( false !== stripos( $header, 'boundary=' ) ) {
$parts = preg_split( '/boundary=/i', trim( $header ) );
$boundary = trim( str_replace( array( "'", '"' ), '', $parts[1] ) );
list( $name, $content ) = explode( ':', trim( $header ), 2 );
$content = trim( $content );
switch ( strtolower( $name ) ) {
// Mainly for legacy -- process a "From:" header if it's there.
$bracket_pos = strpos( $content, '<' );
if ( false !== $bracket_pos ) {
// Text before the bracketed email is the "From" name.
if ( $bracket_pos > 0 ) {
$from_name = substr( $content, 0, $bracket_pos - 1 );
$from_name = str_replace( '"', '', $from_name );
$from_name = trim( $from_name );
$from_email = substr( $content, $bracket_pos + 1 );
$from_email = str_replace( '>', '', $from_email );
$from_email = trim( $from_email );
// Avoid setting an empty $from_email.
} elseif ( '' !== trim( $content ) ) {
$from_email = trim( $content );
if ( strpos( $content, ';' ) !== false ) {
list( $type, $charset_content ) = explode( ';', $content );
$content_type = trim( $type );
if ( false !== stripos( $charset_content, 'charset=' ) ) {
$charset = trim( str_replace( array( 'charset=', '"' ), '', $charset_content ) );
} elseif ( false !== stripos( $charset_content, 'boundary=' ) ) {
$boundary = trim( str_replace( array( 'BOUNDARY=', 'boundary=', '"' ), '', $charset_content ) );
// Avoid setting an empty $content_type.
} elseif ( '' !== trim( $content ) ) {
$content_type = trim( $content );
$cc = array_merge( (array) $cc, explode( ',', $content ) );
$bcc = array_merge( (array) $bcc, explode( ',', $content ) );
$reply_to = array_merge( (array) $reply_to, explode( ',', $content ) );
// Add it to our grand headers array.
$headers[ trim( $name ) ] = trim( $content );
// Empty out the values that may be set.
$phpmailer->clearAllRecipients();
$phpmailer->clearAttachments();
$phpmailer->clearCustomHeaders();
$phpmailer->clearReplyTos();
$phpmailer->AltBody = '';
// Set "From" name and email.
// If we don't have a name from the input headers.
if ( ! isset( $from_name ) ) {
$from_name = 'WordPress';
* If we don't have an email from the input headers, default to wordpress@$sitename
* Some hosts will block outgoing mail from this address if it doesn't exist,
* but there's no easy alternative. Defaulting to admin_email might appear to be
* another option, but some hosts may refuse to relay mail from an unknown domain.
* See https://core.trac.wordpress.org/ticket/5007.
if ( ! isset( $from_email ) ) {
// Get the site domain and get rid of www.
$sitename = wp_parse_url( network_home_url(), PHP_URL_HOST );
if ( 'www.' === substr( $sitename, 0, 4 ) ) {
$sitename = substr( $sitename, 4 );
$from_email = 'wordpress@' . $sitename;
* Filters the email address to send from.
* @param string $from_email Email address to send from.
$from_email = apply_filters( 'wp_mail_from', $from_email );
* Filters the name to associate with the "from" email address.
* @param string $from_name Name associated with the "from" email address.
$from_name = apply_filters( 'wp_mail_from_name', $from_name );
$phpmailer->setFrom( $from_email, $from_name, false );
} catch ( PHPMailer\PHPMailer\Exception $e ) {
$mail_error_data = compact( 'to', 'subject', 'message', 'headers', 'attachments' );
$mail_error_data['phpmailer_exception_code'] = $e->getCode();
/** This filter is documented in wp-includes/pluggable.php */
do_action( 'wp_mail_failed', new WP_Error( 'wp_mail_failed', $e->getMessage(), $mail_error_data ) );
// Set mail's subject and body.
$phpmailer->Subject = $subject;
$phpmailer->Body = $message;
// Set destination addresses, using appropriate methods for handling addresses.
$address_headers = compact( 'to', 'cc', 'bcc', 'reply_to' );
foreach ( $address_headers as $address_header => $addresses ) {
if ( empty( $addresses ) ) {
foreach ( (array) $addresses as $address ) {
// Break $recipient into name and address parts if in the format "Foo <bar@baz.com>".
if ( preg_match( '/(.*)<(.+)>/', $address, $matches ) ) {
if ( count( $matches ) == 3 ) {
$recipient_name = $matches[1];
switch ( $address_header ) {
$phpmailer->addAddress( $address, $recipient_name );
$phpmailer->addCc( $address, $recipient_name );
$phpmailer->addBcc( $address, $recipient_name );
$phpmailer->addReplyTo( $address, $recipient_name );
} catch ( PHPMailer\PHPMailer\Exception $e ) {
// Set to use PHP's mail().
// Set Content-Type and charset.
// If we don't have a content-type from the input headers.
if ( ! isset( $content_type ) ) {
$content_type = 'text/plain';
* Filters the wp_mail() content type.
* @param string $content_type Default wp_mail() content type.
$content_type = apply_filters( 'wp_mail_content_type', $content_type );
$phpmailer->ContentType = $content_type;
// Set whether it's plaintext, depending on $content_type.
if ( 'text/html' === $content_type ) {
$phpmailer->isHTML( true );
// If we don't have a charset from the input headers.
if ( ! isset( $charset ) ) {
$charset = get_bloginfo( 'charset' );
* Filters the default wp_mail() charset.
* @param string $charset Default email charset.
$phpmailer->CharSet = apply_filters( 'wp_mail_charset', $charset );
if ( ! empty( $headers ) ) {
foreach ( (array) $headers as $name => $content ) {
// Only add custom headers not added automatically by PHPMailer.
if ( ! in_array( $name, array( 'MIME-Version', 'X-Mailer' ), true ) ) {
$phpmailer->addCustomHeader( sprintf( '%1$s: %2$s', $name, $content ) );