// }}}
-
/**
* Command statistics
*
* Retrieves the value associated with the key from the memcache server
*
* @param $key array|string key to retrieve
+ * @param $casToken[optional] Float
*
* @return Mixed
*/
- public function get( $key ) {
+ public function get( $key, &$casToken = null ) {
wfProfileIn( __METHOD__ );
if ( $this->_debug ) {
$this->stats['get'] = 1;
}
- $cmd = "get $key\r\n";
+ $cmd = "gets $key\r\n";
if ( !$this->_fwrite( $sock, $cmd ) ) {
wfProfileOut( __METHOD__ );
return false;
}
$val = array();
- $this->_load_items( $sock, $val );
+ $this->_load_items( $sock, $val, $casToken );
if ( $this->_debug ) {
foreach ( $val as $k => $v ) {
$gather = array();
// Send out the requests
foreach ( $socks as $sock ) {
- $cmd = 'get';
+ $cmd = 'gets';
foreach ( $sock_keys[ intval( $sock ) ] as $key ) {
$cmd .= ' ' . $key;
}
// Parse responses
$val = array();
foreach ( $gather as $sock ) {
- $this->_load_items( $sock, $val );
+ $this->_load_items( $sock, $val, $casToken );
}
if ( $this->_debug ) {
return $this->_set( 'set', $key, $value, $exp );
}
+ // }}}
+ // {{{ cas()
+
+ /**
+ * Sets a key to a given value in the memcache if the current value still corresponds
+ * to a known, given value. Returns true if set successfully.
+ *
+ * @param $casToken Float: current known value
+ * @param $key String: key to set value as
+ * @param $value Mixed: value to set
+ * @param $exp Integer: (optional) Expiration time. This can be a number of seconds
+ * to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or
+ * longer must be the timestamp of the time at which the mapping should expire. It
+ * is safe to use timestamps in all cases, regardless of exipration
+ * eg: strtotime("+3 hour")
+ *
+ * @return Boolean: TRUE on success
+ */
+ public function cas( $casToken, $key, $value, $exp = 0 ) {
+ return $this->_set( 'cas', $key, $value, $exp, $casToken );
+ }
+
// }}}
// {{{ set_compress_threshold()
*
* @param $sock Resource: socket to read from
* @param $ret Array: returned values
+ * @param $casToken[optional] Float
* @return boolean True for success, false for failure
*
* @access private
*/
- function _load_items( $sock, &$ret ) {
+ function _load_items( $sock, &$ret, &$casToken = null ) {
+ $results = array();
+
while ( 1 ) {
$decl = $this->_fgets( $sock );
+
if( $decl === false ) {
+ /*
+ * If nothing can be read, something is wrong because we know exactly when
+ * to stop reading (right after "END") and we return right after that.
+ */
return false;
+ } elseif ( preg_match( '/^VALUE (\S+) (\d+) (\d+) (\d+)$/', $decl, $match ) ) {
+ /*
+ * Read all data returned. This can be either one or multiple values.
+ * Save all that data (in an array) to be processed later: we'll first
+ * want to continue reading until "END" before doing anything else,
+ * to make sure that we don't leave our client in a state where it's
+ * output is not yet fully read.
+ */
+ $results[] = array(
+ $match[1], // rkey
+ $match[2], // flags
+ $match[3], // len
+ $match[4], // casToken
+ $this->_fread( $sock, $match[3] + 2 ), // data
+ );
} elseif ( $decl == "END" ) {
- return true;
- } elseif ( preg_match( '/^VALUE (\S+) (\d+) (\d+)$/', $decl, $match ) ) {
- list( $rkey, $flags, $len ) = array( $match[1], $match[2], $match[3] );
- $data = $this->_fread( $sock, $len + 2 );
- if ( $data === false ) {
- return false;
- }
- if ( substr( $data, -2 ) !== "\r\n" ) {
- $this->_handle_error( $sock,
- 'line ending missing from data block from $1' );
+ if ( count( $results ) == 0 ) {
return false;
}
- $data = substr( $data, 0, -2 );
- $ret[$rkey] = $data;
- if ( $this->_have_zlib && $flags & self::COMPRESSED ) {
- $ret[$rkey] = gzuncompress( $ret[$rkey] );
- }
+ /**
+ * All data has been read, time to process the data and build
+ * meaningful return values.
+ */
+ foreach ( $results as $vars ) {
+ list( $rkey, $flags, $len, $casToken, $data ) = $vars;
+
+ if ( $data === false || substr( $data, -2 ) !== "\r\n" ) {
+ $this->_handle_error( $sock,
+ 'line ending missing from data block from $1' );
+ return false;
+ }
+ $data = substr( $data, 0, -2 );
+ $ret[$rkey] = $data;
+
+ if ( $this->_have_zlib && $flags & self::COMPRESSED ) {
+ $ret[$rkey] = gzuncompress( $ret[$rkey] );
+ }
- if ( $flags & self::SERIALIZED ) {
- $ret[$rkey] = unserialize( $ret[$rkey] );
+ /*
+ * This unserialize is the exact reason that we only want to
+ * process data after having read until "END" (instead of doing
+ * this right away): "unserialize" can trigger outside code:
+ * in the event that $ret[$rkey] is a serialized object,
+ * unserializing it will trigger __wakeup() if present. If that
+ * function attempted to read from memcached (while we did not
+ * yet read "END"), these 2 calls would collide.
+ */
+ if ( $flags & self::SERIALIZED ) {
+ $ret[$rkey] = unserialize( $ret[$rkey] );
+ }
}
+ return true;
} else {
$this->_handle_error( $sock, 'Error parsing response from $1' );
return false;
* longer must be the timestamp of the time at which the mapping should expire. It
* is safe to use timestamps in all cases, regardless of exipration
* eg: strtotime("+3 hour")
+ * @param $casToken[optional] Float
*
* @return Boolean
* @access private
*/
- function _set( $cmd, $key, $val, $exp ) {
+ function _set( $cmd, $key, $val, $exp, $casToken = null ) {
if ( !$this->_active ) {
return false;
}
$len = strlen( $val );
if ( $this->_have_zlib && $this->_compress_enable &&
- $this->_compress_threshold && $len >= $this->_compress_threshold )
+ $this->_compress_threshold && $len >= $this->_compress_threshold )
{
$c_val = gzcompress( $val, 9 );
$c_len = strlen( $c_val );
$flags |= self::COMPRESSED;
}
}
- if ( !$this->_fwrite( $sock, "$cmd $key $flags $exp $len\r\n$val\r\n" ) ) {
+
+ $command = "$cmd $key $flags $exp $len";
+ if ( $casToken ) {
+ $command .= " $casToken";
+ }
+
+ if ( !$this->_fwrite( $sock, "$command\r\n$val\r\n" ) ) {
return false;
}
* @param $text string
*/
function _debugprint( $text ) {
- global $wgDebugLogGroups;
- if( !isset( $wgDebugLogGroups['memcached'] ) ) {
- # Prefix message since it will end up in main debug log file
- $text = "memcached: $text";
- }
wfDebugLog( 'memcached', $text );
}
// }}}
}
-
// }}}
class MemCachedClientforWiki extends MWMemcached {
dépôts / lhc / web / wiklou.git / blobdiff