<?php
/**
* IMPORTANT: Do not call any libphutil functions in this class, including
* functions like @{function:id}, @{function:idx} and @{function:pht}. They
* may not have loaded yet.
*/
final class PhutilBootloader {
private static $instance;
private $registeredLibraries = array();
private $libraryMaps = array();
private $extensionMaps = array();
private $extendedMaps = array();
private $currentLibrary = null;
private $classTree = array();
private $inMemoryMaps = array();
public static function newLibrary($name, $path) {
self::getInstance()->registerLibrary($name, $path);
}
public static function getInstance() {
if (!self::$instance) {
self::$instance = new PhutilBootloader();
}
return self::$instance;
}
private function __construct() {
// This method intentionally left blank.
}
public function getClassTree() {
return $this->classTree;
}
public function registerInMemoryLibrary($name, $map) {
$this->registeredLibraries[$name] = "memory:$name";
$this->inMemoryMaps[$name] = $map;
$this->getLibraryMap($name);
}
public function registerLibrary($name, $path) {
// Detect attempts to load the same library multiple times from different
// locations. This might mean you're doing something silly like trying to
// include two different versions of something, or it might mean you're
// doing something subtle like running a different version of 'arc' on a
// working copy of Arcanist.
if (isset($this->registeredLibraries[$name])) {
$old_path = $this->registeredLibraries[$name];
if ($old_path != $path) {
throw new PhutilLibraryConflictException($name, $old_path, $path);
}
}
$this->registeredLibraries[$name] = $path;
// If we're loading libphutil itself, load the utility functions first so
// we can safely call functions like "id()" when handling errors. In
// particular, this improves error behavior when "utils.php" itself can
// not load.
if ($name === 'arcanist') {
$root = $this->getLibraryRoot('arcanist');
$this->executeInclude($root.'/utils/utils.php');
}
// For libphutil v2 libraries, load all functions when we load the library.
if (!class_exists('PhutilSymbolLoader', false)) {
$root = $this->getLibraryRoot('arcanist');
$this->executeInclude($root.'/symbols/PhutilSymbolLoader.php');
}
$loader = new PhutilSymbolLoader();
$loader
->setLibrary($name)
->setType('function');
try {
$loader->selectAndLoadSymbols();
} catch (PhutilBootloaderException $ex) {
// Ignore this, it happens if a global function's file is removed or
// similar. Worst case is that we fatal when calling the function, which
// is no worse than fataling here.
} catch (PhutilMissingSymbolException $ex) {
// Ignore this, it happens if a global function is removed. Everything
// else loaded so proceed forward: worst case is a fatal when we
// hit a function call to a function which no longer exists, which is
// no worse than fataling here.
}
if (empty($_SERVER['PHUTIL_DISABLE_RUNTIME_EXTENSIONS'])) {
$extdir = $path.DIRECTORY_SEPARATOR.'extensions';
if (Filesystem::pathExists($extdir)) {
$extensions = id(new FileFinder($extdir))
->withSuffix('php')
->withType('f')
->withFollowSymlinks(true)
->setForceMode('php')
->find();
foreach ($extensions as $extension) {
$this->loadExtension(
$name,
$path,
$extdir.DIRECTORY_SEPARATOR.$extension);
}
}
}
return $this;
}
public function registerLibraryMap(array $map) {
$this->libraryMaps[$this->currentLibrary] = $map;
return $this;
}
public function getLibraryMap($name) {
if (isset($this->extendedMaps[$name])) {
return $this->extendedMaps[$name];
}
if (empty($this->libraryMaps[$name])) {
$root = $this->getLibraryRoot($name);
$this->currentLibrary = $name;
if (isset($this->inMemoryMaps[$name])) {
$this->libraryMaps[$name] = $this->inMemoryMaps[$name];
} else {
$okay = include $root.'/__phutil_library_map__.php';
if (!$okay) {
throw new PhutilBootloaderException(
"Include of '{$root}/__phutil_library_map__.php' failed!");
}
}
$map = $this->libraryMaps[$name];
$version = isset($map['__library_version__'])
? $map['__library_version__']
: 1;
switch ($version) {
case 1:
throw new Exception(
'libphutil v1 libraries are no longer supported.');
case 2:
// NOTE: In version 2 of the library format, all parents (both
// classes and interfaces) are stored in the 'xmap'. The value is
// either a string for a single parent (the common case) or an array
// for multiple parents.
foreach ($map['xmap'] as $child => $parents) {
foreach ((array)$parents as $parent) {
$this->classTree[$parent][] = $child;
}
}
break;
default:
throw new Exception("Unsupported library version '{$version}'!");
}
}
$map = $this->libraryMaps[$name];
// If there's an extension map for this library, merge the maps.
if (isset($this->extensionMaps[$name])) {
$emap = $this->extensionMaps[$name];
foreach (array('function', 'class', 'xmap') as $dict_key) {
if (!isset($emap[$dict_key])) {
continue;
}
$map[$dict_key] += $emap[$dict_key];
}
}
$this->extendedMaps[$name] = $map;
return $map;
}
public function getLibraryMapWithoutExtensions($name) {
// This just does all the checks to make sure the library is valid, then
// we throw away the result.
$this->getLibraryMap($name);
return $this->libraryMaps[$name];
}
public function getLibraryRoot($name) {
if (empty($this->registeredLibraries[$name])) {
throw new PhutilBootloaderException(
"The phutil library '{$name}' has not been loaded!");
}
return $this->registeredLibraries[$name];
}
public function getAllLibraries() {
return array_keys($this->registeredLibraries);
}
public function loadLibrarySource($library, $source) {
$path = $this->getLibraryRoot($library).'/'.$source;
$this->executeInclude($path);
}
public function loadLibrary($path) {
$this->executeInclude($path.'/__phutil_library_init__.php');
}
private function executeInclude($path) {
// Include the source using `include_once`, but convert any warnings or
// recoverable errors into exceptions.
// Some messages, including "Declaration of X should be compatible with Y",
// do not cause `include_once` to return an error code. Use
// error_get_last() to make sure we're catching everything in every PHP
// version.
// (Also, the severity of some messages changed between versions of PHP.)
// Note that we may enter this method after some earlier, unrelated error.
// In this case, error_get_last() will return information for that error.
// In PHP7 and later we could use error_clear_last() to clear that error,
// but the function does not exist in earlier versions of PHP. Instead,
// check if the value has changed.
// Some parser-like errors, including "class must implement all abstract
// methods", cause PHP to fatal immediately with an E_ERROR. In these
// cases, include_once() does not throw and never returns. We leave
// reporting enabled for these errors since we don't have a way to do
// anything more graceful.
// Likewise, some errors, including "cannot redeclare Class::method()"
// cause PHP to fatal immediately with E_COMPILE_ERROR. Treat these like
// the similar errors which raise E_ERROR.
// See also T12190.
$old_last = error_get_last();
try {
$old = error_reporting(E_ERROR | E_COMPILE_ERROR);
$okay = include_once $path;
error_reporting($old);
} catch (Exception $ex) {
throw $ex;
} catch (ParseError $throwable) {
// NOTE: As of PHP7, syntax errors may raise a ParseError (which is a
// Throwable, not an Exception) with a useless message (like "syntax
// error, unexpected ':'") and a trace which ends a level above this.
// Treating this object normally results in an unusable message which
// does not identify where the syntax error occurred. Converting it to
// a string and taking the first line gives us something reasonable,
// however.
$message = (string)$throwable;
$message = preg_split("/\n/", $message);
$message = reset($message);
throw new Exception($message);
}
if (!$okay) {
throw new Exception("Source file \"{$path}\" failed to load.");
}
$new_last = error_get_last();
if ($new_last !== null) {
if ($new_last !== $old_last) {
$message = $new_last['message'];
throw new Exception(
"Error while loading file \"{$path}\": {$message}");
}
}
}
private function loadExtension($library, $root, $path) {
$old_functions = get_defined_functions();
$old_functions = array_fill_keys($old_functions['user'], true);
$old_classes = array_fill_keys(get_declared_classes(), true);
$old_interfaces = array_fill_keys(get_declared_interfaces(), true);
$this->executeInclude($path);
$new_functions = get_defined_functions();
$new_functions = array_fill_keys($new_functions['user'], true);
$new_classes = array_fill_keys(get_declared_classes(), true);
$new_interfaces = array_fill_keys(get_declared_interfaces(), true);
$add_functions = array_diff_key($new_functions, $old_functions);
$add_classes = array_diff_key($new_classes, $old_classes);
$add_interfaces = array_diff_key($new_interfaces, $old_interfaces);
// NOTE: We can't trust the path we loaded to be the location of these
// symbols, because it might have loaded other paths.
foreach ($add_functions as $func => $ignored) {
$rfunc = new ReflectionFunction($func);
$fpath = Filesystem::resolvePath($rfunc->getFileName(), $root);
$this->extensionMaps[$library]['function'][$func] = $fpath;
}
foreach ($add_classes + $add_interfaces as $class => $ignored) {
$rclass = new ReflectionClass($class);
$cpath = Filesystem::resolvePath($rclass->getFileName(), $root);
$this->extensionMaps[$library]['class'][$class] = $cpath;
$xmap = $rclass->getInterfaceNames();
$parent = $rclass->getParentClass();
if ($parent) {
$xmap[] = $parent->getName();
}
if ($xmap) {
foreach ($xmap as $parent_class) {
$this->classTree[$parent_class][] = $class;
}
if (count($xmap) == 1) {
$xmap = head($xmap);
}
$this->extensionMaps[$library]['xmap'][$class] = $xmap;
}
}
// Clear the extended library cache (should one exist) so we know that
// we need to rebuild it.
unset($this->extendedMaps[$library]);
}
}