【转载】Wordpress源代码分析之settings.php之三

http://hi.baidu.com/wordpressing/blog/item/64b8f538163069f53a87cec7.html

/**
* timer_start() - PHP 4 standard microtime start capture
*
* @access private
* @since 0.71
* @global int $timestart Seconds and Microseconds added together from when function is called
* @return bool Always returns true
*/
function timer_start() {
    global $timestart;
    $mtime = explode(' ', microtime() );
    $mtime = $mtime[1] + $mtime[0];
    $timestart = $mtime;
    return true;
}

microtime -- 返回当前 Unix 时间戳和微秒数。

如果调用时不带可选参数，本函数以 "msec sec" 的格式返回一个字符串，其中 sec 是自 Unix 纪元（0:00:00 January 1, 1970 GMT）起到现在的秒数，msec 是微秒部分。字符串的两部分都是以秒为单位返回的。


/**
* timer_stop() - Return and/or display the time from the page start to when function is called.
*
* You can get the results and print them by doing:
* <code>
* $nTimePageTookToExecute = timer_stop();
* echo $nTimePageTookToExecute;
* </code>
*
* Or instead, you can do:
* <code>
* timer_stop(1);
* </code>
* which will do what the above does. If you need the result, you can assign it to a variable, but
* most cases, you only need to echo it.
*
* @since 0.71
* @global int $timestart Seconds and Microseconds added together from when timer_start() is called
* @global int $timeend   Seconds and Microseconds added together from when function is called
*
* @param int $display Use '0' or null to not echo anything and 1 to echo the total time
* @param int $precision The amount of digits from the right of the decimal to display. Default is 3.
* @return float The "second.microsecond" finished time calculation
*/
function timer_stop($display = 0, $precision = 3) { //if called like timer_stop(1), will echo $timetotal
    global $timestart, $timeend;
    $mtime = microtime();
    $mtime = explode(' ',$mtime);
    $mtime = $mtime[1] + $mtime[0];
    $timeend = $mtime;
    $timetotal = $timeend-$timestart;
    $r = ( function_exists('number_format_i18n') ) ? number_format_i18n($timetotal, $precision) : number_format($timetotal, $precision);
    if ( $display )
        echo $r;
    return $r;
}
timer_start();

时间函数，开始记录时间，结束时间是timer_stop


// Add define('WP_DEBUG',true); to wp-config.php to enable display of notices during development.
/*在 WordPress 2.3.1 版本中，又增加了新的参数，调试参数（WP_DEBUG）。这是一个逻辑参数，也就是只有是（true）和否（false）两个选项。如果设置为是，则 WordPress 发生错误是，会将错误报告给用户。如果你没有在 wp-config.php 中设置此参数，默认参数为否，即不发送错误报告。*/
if (defined('WP_DEBUG') and WP_DEBUG == true) {
     error_reporting(E_ALL);
} else {
     error_reporting(E_ALL ^ E_NOTICE ^ E_USER_NOTICE);
}

// For an advanced caching plugin to use, static because you would only want one
if ( defined('WP_CACHE') )
     @include ABSPATH . 'wp-content/advanced-cache.php';

/**
* Stores the location of the WordPress directory of functions, classes, and core content.
*
* @since 1.0.0
*/
define('WPINC', 'wp-includes');

if ( !defined('LANGDIR') ) {
    /**
      * Stores the location of the language directory. First looks for language folder in wp-content
      * and uses that folder if it exists. Or it uses the "languages" folder in WPINC.
      *
      * @since 2.1.0
      */
    if ( file_exists(ABSPATH . 'wp-content/languages') && @is_dir(ABSPATH . 'wp-content/languages') )
        define('LANGDIR', 'wp-content/languages'); // no leading slash, no trailing slash
    else
         define('LANGDIR', WPINC . '/languages'); // no leading slash, no trailing slash
}

关于语言的操作。如果存在wp-content/languages文件夹，就定义常量LANGDIR为wp-content/languages

否则就是wp-includes/languages

/**
* Allows for the plugins directory to be moved from the default location.
*
* This isn't used everywhere. Constant is not used in plugin_basename()
* which might cause conflicts with changing this.
*
* @since 2.1
*/
if ( !defined('PLUGINDIR') )
    define('PLUGINDIR', 'wp-content/plugins'); // no leading slash, no trailing slash

require (ABSPATH . WPINC . '/compat.php');
require (ABSPATH . WPINC . '/functions.php');
require (ABSPATH . WPINC . '/classes.php');

require_wp_db();

if ( !empty($wpdb->error) )
     dead_db();

$prefix = $wpdb->set_prefix($table_prefix);

if ( is_wp_error($prefix) )
     wp_die('<strong>ERROR</strong>: <code>$table_prefix</code> in <code>wp-config.php</code> can only contain numbers, letters, and underscores.');

if ( file_exists(ABSPATH . 'wp-content/object-cache.php') )
    require_once (ABSPATH . 'wp-content/object-cache.php');
else
     require_once (ABSPATH . WPINC . '/cache.php');

wp_cache_init();

require (ABSPATH . WPINC . '/plugin.php');
require (ABSPATH . WPINC . '/default-filters.php');
include_once(ABSPATH . WPINC . '/streams.php');
include_once(ABSPATH . WPINC . '/gettext.php');
require_once (ABSPATH . WPINC . '/l10n.php');

if ( !is_blog_installed() && (strpos($_SERVER['PHP_SELF'], 'install.php') === false && !defined('WP_INSTALLING')) ) {
    if ( defined('WP_SITEURL') )
        $link = WP_SITEURL . '/wp-admin/install.php';
    elseif (strpos($_SERVER['PHP_SELF'], 'wp-admin') !== false)
        $link = preg_replace('|/wp-admin/?.*?$|', '/', $_SERVER['PHP_SELF']) . 'wp-admin/install.php';
    else
        $link = preg_replace('|/[^/]+?$|', '/', $_SERVER['PHP_SELF']) . 'wp-admin/install.php';
    require_once(ABSPATH . WPINC . '/kses.php');
    require_once(ABSPATH . WPINC . '/pluggable.php');
     wp_redirect($link);
    die(); // have to die here ~ Mark
}

require (ABSPATH . WPINC . '/formatting.php');
require (ABSPATH . WPINC . '/capabilities.php');
require (ABSPATH . WPINC . '/query.php');
require (ABSPATH . WPINC . '/theme.php');
require (ABSPATH . WPINC . '/user.php');
require (ABSPATH . WPINC . '/general-template.php');
require (ABSPATH . WPINC . '/link-template.php');
require (ABSPATH . WPINC . '/author-template.php');
require (ABSPATH . WPINC . '/post.php');
require (ABSPATH . WPINC . '/post-template.php');
require (ABSPATH . WPINC . '/category.php');
require (ABSPATH . WPINC . '/category-template.php');
require (ABSPATH . WPINC . '/comment.php');
require (ABSPATH . WPINC . '/comment-template.php');
require (ABSPATH . WPINC . '/rewrite.php');
require (ABSPATH . WPINC . '/feed.php');
require (ABSPATH . WPINC . '/bookmark.php');
require (ABSPATH . WPINC . '/bookmark-template.php');
require (ABSPATH . WPINC . '/kses.php');
require (ABSPATH . WPINC . '/cron.php');
require (ABSPATH . WPINC . '/version.php');
require (ABSPATH . WPINC . '/deprecated.php');
require (ABSPATH . WPINC . '/script-loader.php');
require (ABSPATH . WPINC . '/taxonomy.php');
require (ABSPATH . WPINC . '/update.php');
require (ABSPATH . WPINC . '/canonical.php');
require (ABSPATH . WPINC . '/shortcodes.php');
require (ABSPATH . WPINC . '/media.php');

if (strpos($_SERVER['PHP_SELF'], 'install.php') === false) {
    // Used to guarantee unique hash cookies
    $cookiehash = md5(get_option('siteurl'));
    /**
      * Used to guarantee unique hash cookies
      * @since 1.5
      */
    define('COOKIEHASH', $cookiehash);
}