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/**
	 * Parses the request to find the correct WordPress query.
	 *
	 * Sets up the query variables based on the request. There are also many
	 * filters and actions that can be used to further manipulate the result.
	 *
	 * @since 2.0.0
	 * @since 6.0.0 A return value was added.
	 *
	 * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
	 *
	 * @param array|string $extra_query_vars Set the extra query variables.
	 * @return bool Whether the request was parsed.
	 */
	public function parse_request( $extra_query_vars = '' ) {
		global $wp_rewrite;

		/**
		 * Filters whether to parse the request.
		 *
		 * @since 3.5.0
		 *
		 * @param bool         $bool             Whether or not to parse the request. Default true.
		 * @param WP           $wp               Current WordPress environment instance.
		 * @param array|string $extra_query_vars Extra passed query variables.
		 */
		if ( ! apply_filters( 'do_parse_request', true, $this, $extra_query_vars ) ) {
			return false;
		}

		$this->query_vars     = array();
		$post_type_query_vars = array();

		if ( is_array( $extra_query_vars ) ) {
			$this->extra_query_vars = & $extra_query_vars;
		} elseif ( ! empty( $extra_query_vars ) ) {
			parse_str( $extra_query_vars, $this->extra_query_vars );
		}
		// Process PATH_INFO, REQUEST_URI, and 404 for permalinks.

		// Fetch the rewrite rules.
		$rewrite = $wp_rewrite->wp_rewrite_rules();

		if ( ! empty( $rewrite ) ) {
			// If we match a rewrite rule, this will be cleared.
			$error               = '404';
			$this->did_permalink = true;

			$pathinfo         = isset( $_SERVER['PATH_INFO'] ) ? $_SERVER['PATH_INFO'] : '';
			list( $pathinfo ) = explode( '?', $pathinfo );
			$pathinfo         = str_replace( '%', '%25', $pathinfo );

			list( $req_uri ) = explode( '?', $_SERVER['REQUEST_URI'] );
			$self            = $_SERVER['PHP_SELF'];

			$home_path       = parse_url( home_url(), PHP_URL_PATH );
			$home_path_regex = '';
			if ( is_string( $home_path ) && '' !== $home_path ) {
				$home_path       = trim( $home_path, '/' );
				$home_path_regex = sprintf( '|^%s|i', preg_quote( $home_path, '|' ) );
			}

			/*
			 * Trim path info from the end and the leading home path from the front.
			 * For path info requests, this leaves us with the requesting filename, if any.
			 * For 404 requests, this leaves us with the requested permalink.
			 */
			$req_uri  = str_replace( $pathinfo, '', $req_uri );
			$req_uri  = trim( $req_uri, '/' );
			$pathinfo = trim( $pathinfo, '/' );
			$self     = trim( $self, '/' );

			if ( ! empty( $home_path_regex ) ) {
				$req_uri  = preg_replace( $home_path_regex, '', $req_uri );
				$req_uri  = trim( $req_uri, '/' );
				$pathinfo = preg_replace( $home_path_regex, '', $pathinfo );
				$pathinfo = trim( $pathinfo, '/' );
				$self     = preg_replace( $home_path_regex, '', $self );
				$self     = trim( $self, '/' );
			}

			// The requested permalink is in $pathinfo for path info requests and $req_uri for other requests.
			if ( ! empty( $pathinfo ) && ! preg_match( '|^.*' . $wp_rewrite->index . '$|', $pathinfo ) ) {
				$requested_path = $pathinfo;
			} else {
				// If the request uri is the index, blank it out so that we don't try to match it against a rule.
				if ( $req_uri === $wp_rewrite->index ) {
					$req_uri = '';
				}

				$requested_path = $req_uri;
			}

			$requested_file = $req_uri;

			$this->request = $requested_path;

			// Look for matches.
			$request_match = $requested_path;
			if ( empty( $request_match ) ) {
				// An empty request could only match against ^$ regex.
				if ( isset( $rewrite['$'] ) ) {
					$this->matched_rule = '$';
					$query              = $rewrite['$'];
					$matches            = array( '' );
				}
			} else {
				foreach ( (array) $rewrite as $match => $query ) {
					// If the requested file is the anchor of the match, prepend it to the path info.
					if ( ! empty( $requested_file )
						&& str_starts_with( $match, $requested_file )
						&& $requested_file !== $requested_path
					) {
						$request_match = $requested_file . '/' . $requested_path;
					}

					if ( preg_match( "#^$match#", $request_match, $matches )
						|| preg_match( "#^$match#", urldecode( $request_match ), $matches )
					) {

						if ( $wp_rewrite->use_verbose_page_rules
							&& preg_match( '/pagename=\$matches\[([0-9]+)\]/', $query, $varmatch )
						) {
							// This is a verbose page match, let's check to be sure about it.
							$page = get_page_by_path( $matches[ $varmatch[1] ] );

							if ( ! $page ) {
								continue;
							}

							$post_status_obj = get_post_status_object( $page->post_status );

							if ( ! $post_status_obj->public && ! $post_status_obj->protected
								&& ! $post_status_obj->private && $post_status_obj->exclude_from_search
							) {
								continue;
							}
						}

						// Got a match.
						$this->matched_rule = $match;
						break;
					}
				}
			}

			if ( ! empty( $this->matched_rule ) ) {
				// Trim the query of everything up to the '?'.
				$query = preg_replace( '!^.+\?!', '', $query );

				// Substitute the substring matches into the query.
				$query = addslashes( WP_MatchesMapRegex::apply( $query, $matches ) );

				$this->matched_query = $query;

				// Parse the query.
				parse_str( $query, $perma_query_vars );

				// If we're processing a 404 request, clear the error var since we found something.
				if ( '404' === $error ) {
					unset( $error, $_GET['error'] );
				}
			}

			// If req_uri is empty or if it is a request for ourself, unset error.
			if ( empty( $requested_path ) || $requested_file === $self
				|| str_contains( $_SERVER['PHP_SELF'], 'wp-admin/' )
			) {
				unset( $error, $_GET['error'] );

				if ( isset( $perma_query_vars ) && str_contains( $_SERVER['PHP_SELF'], 'wp-admin/' ) ) {
					unset( $perma_query_vars );
				}

				$this->did_permalink = false;
			}
		}

		/**
		 * Filters the query variables allowed before processing.
		 *
		 * Allows (publicly allowed) query vars to be added, removed, or changed prior
		 * to executing the query. Needed to allow custom rewrite rules using your own arguments
		 * to work, or any other custom query variables you want to be publicly available.
		 *
		 * @since 1.5.0
		 *
		 * @param string[] $public_query_vars The array of allowed query variable names.
		 */
		$this->public_query_vars = apply_filters( 'query_vars', $this->public_query_vars );

		foreach ( get_post_types( array(), 'objects' ) as $post_type => $t ) {
			if ( is_post_type_viewable( $t ) && $t->query_var ) {
				$post_type_query_vars[ $t->query_var ] = $post_type;
			}
		}

		foreach ( $this->public_query_vars as $wpvar ) {
			if ( isset( $this->extra_query_vars[ $wpvar ] ) ) {
				$this->query_vars[ $wpvar ] = $this->extra_query_vars[ $wpvar ];
			} elseif ( isset( $_GET[ $wpvar ] ) && isset( $_POST[ $wpvar ] )
				&& $_GET[ $wpvar ] !== $_POST[ $wpvar ]
			) {
				wp_die(
					__( 'A variable mismatch has been detected.' ),
					__( 'Sorry, you are not allowed to view this item.' ),
					400
				);
			} elseif ( isset( $_POST[ $wpvar ] ) ) {
				$this->query_vars[ $wpvar ] = $_POST[ $wpvar ];
			} elseif ( isset( $_GET[ $wpvar ] ) ) {
				$this->query_vars[ $wpvar ] = $_GET[ $wpvar ];
			} elseif ( isset( $perma_query_vars[ $wpvar ] ) ) {
				$this->query_vars[ $wpvar ] = $perma_query_vars[ $wpvar ];
			}

			if ( ! empty( $this->query_vars[ $wpvar ] ) ) {
				if ( ! is_array( $this->query_vars[ $wpvar ] ) ) {
					$this->query_vars[ $wpvar ] = (string) $this->query_vars[ $wpvar ];
				} else {
					foreach ( $this->query_vars[ $wpvar ] as $vkey => $v ) {
						if ( is_scalar( $v ) ) {
							$this->query_vars[ $wpvar ][ $vkey ] = (string) $v;
						}
					}
				}

				if ( isset( $post_type_query_vars[ $wpvar ] ) ) {
					$this->query_vars['post_type'] = $post_type_query_vars[ $wpvar ];
					$this->query_vars['name']      = $this->query_vars[ $wpvar ];
				}
			}
		}

		// Convert urldecoded spaces back into '+'.
		foreach ( get_taxonomies( array(), 'objects' ) as $taxonomy => $t ) {
			if ( $t->query_var && isset( $this->query_vars[ $t->query_var ] ) ) {
				$this->query_vars[ $t->query_var ] = str_replace( ' ', '+', $this->query_vars[ $t->query_var ] );
			}
		}

		// Don't allow non-publicly queryable taxonomies to be queried from the front end.
		if ( ! is_admin() ) {
			foreach ( get_taxonomies( array( 'publicly_queryable' => false ), 'objects' ) as $taxonomy => $t ) {
				/*
				 * Disallow when set to the 'taxonomy' query var.
				 * Non-publicly queryable taxonomies cannot register custom query vars. See register_taxonomy().
				 */
				if ( isset( $this->query_vars['taxonomy'] ) && $taxonomy === $this->query_vars['taxonomy'] ) {
					unset( $this->query_vars['taxonomy'], $this->query_vars['term'] );
				}
			}
		}

		// Limit publicly queried post_types to those that are 'publicly_queryable'.
		if ( isset( $this->query_vars['post_type'] ) ) {
			$queryable_post_types = get_post_types( array( 'publicly_queryable' => true ) );

			if ( ! is_array( $this->query_vars['post_type'] ) ) {
				if ( ! in_array( $this->query_vars['post_type'], $queryable_post_types, true ) ) {
					unset( $this->query_vars['post_type'] );
				}
			} else {
				$this->query_vars['post_type'] = array_intersect( $this->query_vars['post_type'], $queryable_post_types );
			}
		}

		// Resolve conflicts between posts with numeric slugs and date archive queries.
		$this->query_vars = wp_resolve_numeric_slug_conflicts( $this->query_vars );

		foreach ( (array) $this->private_query_vars as $var ) {
			if ( isset( $this->extra_query_vars[ $var ] ) ) {
				$this->query_vars[ $var ] = $this->extra_query_vars[ $var ];
			}
		}

		if ( isset( $error ) ) {
			$this->query_vars['error'] = $error;
		}

		/**
		 * Filters the array of parsed query variables.
		 *
		 * @since 2.1.0
		 *
		 * @param array $query_vars The array of requested query variables.
		 */
		$this->query_vars = apply_filters( 'request', $this->query_vars );

		/**
		 * Fires once all query variables for the current request have been parsed.
		 *
		 * @since 2.1.0
		 *
		 * @param WP $wp Current WordPress environment instance (passed by reference).
		 */
		do_action_ref_array( 'parse_request', array( &$this ) );

		return true;
	}

---

上述代码是WordPress核心类WP中parse_request方法的详细实现。这个方法负责解析传入的URL或请求，以确定应执行哪个WordPress查询。以下是对此方法的作用和工作方式的解释，分解为其关键组件：

parse_request的目的

parse_request方法旨在根据传入请求设置查询变量。它确定请求应如何处理——无论是渲染文章、页面、类别列表还是处理404错误。

关键步骤和操作

1. 过滤提前退出：方法首先检查是否应继续解析请求，使用do_parse_request过滤器。插件可以使用此过滤器来跳过解析过程。
2. 初始化：

• 清除任何之前的查询变量。
• 初始化本地变量以处理URL的不同组件。

1. 处理额外的查询变量：如果提供了任何额外的查询变量，它们将被整合到查询处理中。
2. 应用重写规则：

• 从$wp_rewrite检索WordPress重写规则。
• 处理请求URI和路径信息，去除家庭URL路径，留下将与重写规则匹配的相对路径或查询字符串。

1. 与重写规则匹配：

• 迭代重写规则以找到与处理后的请求路径的匹配项。
• 如果找到匹配，相应的WordPress查询变量将根据重写规则设置。

1. 文章类型和分类法处理：

• 将与文章类型或分类法相关的任何查询变量映射到其相应的查询。
• 确保只能查询公开可查询的文章类型和分类法。

1. 安全和清洁：

• 处理GET和POST请求之间潜在的变量冲突。
• 过滤查询变量以确保最终查询中只包含允许的键。

1. 最终查询变量准备：

• 应用过滤器以修改或验证查询变量列表。
• 解决URL中的数字slug冲突。

1. 动作钩子：

• 执行操作，允许插件在解析查询变量后执行操作。

结论

parse_request函数是WordPress解释和响应URL的能力的核心部分。它使用重写规则将URL映射到查询变量，处理来自GET和POST请求的传入变量，并确保只执行允许的查询。这个方法对于确保WordPress可以为不同的URL提供正确的内容至关重要，无论这些URL指向文章、页面、存档还是自定义文章类型和分类法。

开发中的使用

开发人员可以使用提供的钩子（do_parse_request、query_vars、request和parse_request）来扩展或修改这种行为，以定制WordPress对不同请求的响应，这对于需要专门路由的自定义插件或主题特别有用。

function wp_validate_auth_cookie( $cookie = '', $scheme = '' ) {
		$cookie_elements = wp_parse_auth_cookie( $cookie, $scheme );
		if ( ! $cookie_elements ) {
			/**
			 * Fires if an authentication cookie is malformed.
			 *
			 * @since 2.7.0
			 *
			 * @param string $cookie Malformed auth cookie.
			 * @param string $scheme Authentication scheme. Values include 'auth', 'secure_auth',
			 *                       or 'logged_in'.
			 */
			do_action( 'auth_cookie_malformed', $cookie, $scheme );
			return false;
		}

		$scheme     = $cookie_elements['scheme'];
		$username   = $cookie_elements['username'];
		$hmac       = $cookie_elements['hmac'];
		$token      = $cookie_elements['token'];
		$expired    = $cookie_elements['expiration'];
		$expiration = $cookie_elements['expiration'];

		// Allow a grace period for POST and Ajax requests.
		if ( wp_doing_ajax() || 'POST' === $_SERVER['REQUEST_METHOD'] ) {
			$expired += HOUR_IN_SECONDS;
		}

		// Quick check to see if an honest cookie has expired.
		if ( $expired < time() ) {
			/**
			 * Fires once an authentication cookie has expired.
			 *
			 * @since 2.7.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_expired', $cookie_elements );
			return false;
		}

		$user = get_user_by( 'login', $username );
		if ( ! $user ) {
			/**
			 * Fires if a bad username is entered in the user authentication process.
			 *
			 * @since 2.7.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_bad_username', $cookie_elements );
			return false;
		}

		$pass_frag = substr( $user->user_pass, 8, 4 );

		$key = wp_hash( $username . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );

		// If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
		$algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
		$hash = hash_hmac( $algo, $username . '|' . $expiration . '|' . $token, $key );

		if ( ! hash_equals( $hash, $hmac ) ) {
			/**
			 * Fires if a bad authentication cookie hash is encountered.
			 *
			 * @since 2.7.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_bad_hash', $cookie_elements );
			return false;
		}

		$manager = WP_Session_Tokens::get_instance( $user->ID );
		if ( ! $manager->verify( $token ) ) {
			/**
			 * Fires if a bad session token is encountered.
			 *
			 * @since 4.0.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_bad_session_token', $cookie_elements );
			return false;
		}

		// Ajax/POST grace period set above.
		if ( $expiration < time() ) {
			$GLOBALS['login_grace_period'] = 1;
		}

		/**
		 * Fires once an authentication cookie has been validated.
		 *
		 * @since 2.7.0
		 *
		 * @param string[] $cookie_elements {
		 *     Authentication cookie components.
		 *
		 *     @type string $username   User's username.
		 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
		 *     @type string $token      User's session token used.
		 *     @type string $hmac       The security hash for the cookie.
		 *     @type string $scheme     The cookie scheme to use.
		 * }
		 * @param WP_User  $user            User object.
		 */
		do_action( 'auth_cookie_valid', $cookie_elements, $user );

		return $user->ID;
	}

---

这个PHP函数 wp_validate_auth_cookie() 是WordPress的身份验证系统的一部分。它用于验证用户登录时每个请求发送的身份验证cookie。该函数有两个可选参数：$cookie 和 $scheme。

函数首先使用 wp_parse_auth_cookie() 函数解析身份验证cookie。如果cookie格式错误或不存在，函数会触发 auth_cookie_malformed 动作并返回 false。

接下来，它从解析的cookie中提取各种元素，包括方案、用户名、HMAC（用于数据完整性的一种加密哈希）、令牌和过期时间。

然后，函数检查请求是否为AJAX或POST请求。如果是，它会将cookie的过期时间延长一小时。这是一个宽限期，用于允许长时间运行的操作。

接着，函数检查cookie是否已过期。如果已过期，它会触发 auth_cookie_expired 动作并返回 false。

接下来，它检索与cookie中的用户名关联的用户。如果不存在这样的用户，它会触发 auth_cookie_bad_username 动作并返回 false。

然后，函数通过哈希cookie和用户密码的各种元素来生成一个密钥。它使用这个密钥来生成用户名、过期时间和令牌的哈希。如果生成的哈希与cookie中的HMAC不匹配，它会触发 auth_cookie_bad_hash 动作并返回 false。

接下来，它使用 WP_Session_Tokens::get_instance() 方法验证会话令牌。如果令牌无效，它会触发 auth_cookie_bad_session_token 动作并返回 false。

如果此时cookie的过期时间已过（只有在请求是AJAX或POST请求并且已应用宽限期的情况下才可能发生），它会将全局 login_grace_period 变量设置为 1。

最后，如果所有检查都通过，函数会触发 auth_cookie_valid 动作并返回用户的ID，表示身份验证cookie有效。

<?php
/**
 * Bootstrap file for setting the ABSPATH constant
 * and loading the wp-config.php file. The wp-config.php
 * file will then load the wp-settings.php file, which
 * will then set up the WordPress environment.
 *
 * If the wp-config.php file is not found then an error
 * will be displayed asking the visitor to set up the
 * wp-config.php file.
 *
 * Will also search for wp-config.php in WordPress' parent
 * directory to allow the WordPress directory to remain
 * untouched.
 *
 * @package WordPress
 */

/** Define ABSPATH as this file's directory */
if ( ! defined( 'ABSPATH' ) ) {
	define( 'ABSPATH', __DIR__ . '/' );
}

/*
 * The error_reporting() function can be disabled in php.ini. On systems where that is the case,
 * it's best to add a dummy function to the wp-config.php file, but as this call to the function
 * is run prior to wp-config.php loading, it is wrapped in a function_exists() check.
 */
if ( function_exists( 'error_reporting' ) ) {
	/*
	 * Initialize error reporting to a known set of levels.
	 *
	 * This will be adapted in wp_debug_mode() located in wp-includes/load.php based on WP_DEBUG.
	 * @see https://www.php.net/manual/en/errorfunc.constants.php List of known error levels.
	 */
	error_reporting( E_CORE_ERROR | E_CORE_WARNING | E_COMPILE_ERROR | E_ERROR | E_WARNING | E_PARSE | E_USER_ERROR | E_USER_WARNING | E_RECOVERABLE_ERROR );
}

/*
 * If wp-config.php exists in the WordPress root, or if it exists in the root and wp-settings.php
 * doesn't, load wp-config.php. The secondary check for wp-settings.php has the added benefit
 * of avoiding cases where the current directory is a nested installation, e.g. / is WordPress(a)
 * and /blog/ is WordPress(b).
 *
 * If neither set of conditions is true, initiate loading the setup process.
 */
if ( file_exists( ABSPATH . 'wp-config.php' ) ) {

	/** The config file resides in ABSPATH */
	require_once ABSPATH . 'wp-config.php';

} elseif ( @file_exists( dirname( ABSPATH ) . '/wp-config.php' ) && ! @file_exists( dirname( ABSPATH ) . '/wp-settings.php' ) ) {

	/** The config file resides one level above ABSPATH but is not part of another installation */
	require_once dirname( ABSPATH ) . '/wp-config.php';

} else {

	// A config file doesn't exist.

	define( 'WPINC', 'wp-includes' );
	require_once ABSPATH . WPINC . '/version.php';
	require_once ABSPATH . WPINC . '/compat.php';
	require_once ABSPATH . WPINC . '/load.php';

	// Check for the required PHP version and for the MySQL extension or a database drop-in.
	wp_check_php_mysql_versions();

	// Standardize $_SERVER variables across setups.
	wp_fix_server_vars();

	define( 'WP_CONTENT_DIR', ABSPATH . 'wp-content' );
	require_once ABSPATH . WPINC . '/functions.php';

	$path = wp_guess_url() . '/wp-admin/setup-config.php';

	// Redirect to setup-config.php.
	if ( ! str_contains( $_SERVER['REQUEST_URI'], 'setup-config' ) ) {
		header( 'Location: ' . $path );
		exit;
	}

	wp_load_translations_early();

	// Die with an error message.
	$die = '<p>' . sprintf(
		/* translators: %s: wp-config.php */
		__( "There doesn't seem to be a %s file. It is needed before the installation can continue." ),
		'<code>wp-config.php</code>'
	) . '</p>';
	$die .= '<p>' . sprintf(
		/* translators: 1: Documentation URL, 2: wp-config.php */
		__( 'Need more help? <a href="%1$s">Read the support article on %2$s</a>.' ),
		__( 'https://wordpress.org/documentation/article/editing-wp-config-php/' ),
		'<code>wp-config.php</code>'
	) . '</p>';
	$die .= '<p>' . sprintf(
		/* translators: %s: wp-config.php */
		__( "You can create a %s file through a web interface, but this doesn't work for all server setups. The safest way is to manually create the file." ),
		'<code>wp-config.php</code>'
	) . '</p>';
	$die .= '<p><a href="' . $path . '" class="button button-large">' . __( 'Create a Configuration File' ) . '</a></p>';

	wp_die( $die, __( 'WordPress &rsaquo; Error' ) );
}

---

这段PHP脚本是WordPress应用的一部分，它的主要目的是加载一些必要的文件，并进行一些基本的环境检查。

首先，它加载了一些核心的WordPress文件，包括版本信息(version.php)、兼容性函数(compat.php)和加载函数(load.php)。

然后，它调用wp_check_php_mysql_versions()函数来检查当前环境的PHP版本以及是否安装了MySQL扩展或者数据库插件。

接着，它调用wp_fix_server_vars()函数来标准化$_SERVER变量，以确保在不同的环境下这些变量的行为是一致的。

然后，它定义了WP_CONTENT_DIR常量，这个常量指向WordPress的内容目录，然后加载了一些基本的WordPress函数(functions.php)。

接下来，它构造了一个指向setup-config.php的URL，并检查当前的请求URL是否包含setup-config，如果不包含，那么就会重定向到setup-config.php。

然后，它调用wp_load_translations_early()函数来加载早期的翻译。

最后，如果wp-config.php文件不存在，它会显示一个错误信息，告诉用户需要wp-config.php文件才能继续安装，并提供了一个链接到编辑wp-config.php文件的支持文章，以及一个创建配置文件的按钮。如果用户点击这个按钮，就会被重定向到setup-config.php。

如果所有的检查都通过，那么WordPress的安装过程就可以开始了。