root/scripts/dev/check_parameters.php

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. error
  2. update_lineno
  3. get_vars
  4. check_param
  5. get_params
  6. check_function
  7. recurse

<?php
/*
  +----------------------------------------------------------------------+
  | PHP Version 5                                                        |
  +----------------------------------------------------------------------+
  | Copyright (c) 1997-2007 The PHP Group                                |
  +----------------------------------------------------------------------+
  | This source file is subject to version 3.01 of the PHP license,      |
  | that is bundled with this package in the file LICENSE, and is        |
  | available through the world-wide-web at the following url:           |
  | http://www.php.net/license/3_01.txt                                  |
  | If you did not receive a copy of the PHP license and are unable to   |
  | obtain it through the world-wide-web, please send a note to          |
  | license@php.net so we can mail you a copy immediately.               |
  +----------------------------------------------------------------------+
  | Author: Nuno Lopes <nlopess@php.net>                                 |
  +----------------------------------------------------------------------+
*/

/* $Id$ */


define('REPORT_LEVEL', 2); // 0 reports less false-positives. up to level 5.
define('VERSION', '5.2');  // minimum is 5.2
define('PHPDIR', realpath(dirname(__FILE__) . '/../..'));


// be sure you have enough memory and stack for PHP. pcre will push the limits!
ini_set('pcre.backtrack_limit', 10000000);


// ------------------------ end of config ----------------------------


$API_params = array(
        'a' => array('zval**'), // array as zval*
        'b' => array('zend_bool*'), // boolean
        'C' => array('zend_class_entry**'), // class
        'd' => array('double*'), // double
        'f' => array('zend_fcall_info*', 'zend_fcall_info_cache*'), // function
        'h' => array('HashTable**'), // array as an HashTable*
        'l' => array('long*'), // long
        'o' => array('zval**'), //object
        'O' => array('zval**', 'zend_class_entry*'), // object of given type
        'r' => array('zval**'), // resource
        's' => array('char**', 'int*'), // string
        'z' => array('zval**'), // zval*
        'Z' => array('zval***') // zval**
);

// specific to PHP >= 6
if (version_compare(VERSION, '6', 'ge')) {
        $API_params['S'] = $API_params['s']; // binary string
        $API_params['t'] = array('zstr*', 'int*', 'zend_uchar*'); // text
        $API_params['T'] = $API_params['t'];
        $API_params['u'] = array('UChar**', 'int*'); // unicode
        $API_params['U'] = $API_params['u'];
}


/** reports an error, according to its level */
function error($str, $level = 0)
{
        global $current_file, $current_function, $line;

        if ($level <= REPORT_LEVEL) {
                if (strpos($current_file,PHPDIR) === 0) {
                        $filename = substr($current_file, strlen(PHPDIR)+1); 
                } else {
                        $filename = $current_file;
                }
                echo $filename , " [$line] $current_function : $str\n";
        }
}


/** this updates the global var $line (for error reporting) */
function update_lineno($offset)
{
        global $lines_offset, $line;

        $left  = 0;
        $right = $count = count($lines_offset)-1;

        // a nice binary search :)
        do {
                $mid = intval(($left + $right)/2);
                $val = $lines_offset[$mid];

                if ($val < $offset) {
                        if (++$mid > $count || $lines_offset[$mid] > $offset) {
                                $line = $mid;
                                return;
                        } else {
                                $left = $mid;
                        }
                } else if ($val > $offset) {
                        if ($lines_offset[--$mid] < $offset) {
                                $line = $mid+1;
                                return;
                        } else {
                                $right = $mid;
                        }
                } else {
                        $line = $mid+1;
                        return;
                }
        } while (true);
}


/** parses the sources and fetches its vars name, type and if they are initialized or not */
function get_vars($txt)
{
        $ret =  array();
        preg_match_all('/((?:(?:unsigned|struct)\s+)?\w+)(?:\s*(\*+)\s+|\s+(\**))(\w+(?:\[\s*\w*\s*\])?)\s*(?:(=)[^,;]+)?((?:\s*,\s*\**\s*\w+(?:\[\s*\w*\s*\])?\s*(?:=[^,;]+)?)*)\s*;/S', $txt, $m, PREG_SET_ORDER);

        foreach ($m as $x) {
                // the first parameter is special
                if (!in_array($x[1], array('else', 'endif', 'return'))) // hack to skip reserved words
                        $ret[$x[4]] = array($x[1] . $x[2] . $x[3], $x[5]);

                // are there more vars?
                if ($x[6]) {
                        preg_match_all('/(\**)\s*(\w+(?:\[\s*\w*\s*\])?)\s*(=?)/S', $x[6], $y, PREG_SET_ORDER);
                        foreach ($y as $z) {
                                $ret[$z[2]] = array($x[1] . $z[1], $z[3]);
                        }
                }
        }

//      if ($GLOBALS['current_function'] == 'for_debugging') { print_r($m);print_r($ret); }
        return $ret;
}


/** run diagnostic checks against one var. */
function check_param($db, $idx, $exp, $optional)
{
        global $error_few_vars_given;

        if ($idx >= count($db)) {
                if (!$error_few_vars_given) {
                        error("too few variables passed to function");
                        $error_few_vars_given = true;
                }
                return;
        } elseif ($db[$idx][0] === '**dummy**') {
                return;
        }

        if ($db[$idx][1] != $exp) {
                error("{$db[$idx][0]}: expected '$exp' but got '{$db[$idx][1]}' [".($idx+1).']');
        }

        if ($optional && !$db[$idx][2]) {
                error("optional var not initialized: {$db[$idx][0]} [".($idx+1).']', 1);

        } elseif (!$optional && $db[$idx][2]) {
                error("not optional var is initialized: {$db[$idx][0]} [".($idx+1).']', 2);
        }
}


/** fetch params passed to zend_parse_params*() */
function get_params($vars, $str)
{
        $ret = array();
        preg_match_all('/(?:\([^)]+\))?(&?)([\w>.()-]+(?:\[\w+\])?)\s*,?((?:\)*\s*=)?)/S', $str, $m, PREG_SET_ORDER);

        foreach ($m as $x) {
                $name = $x[2];

                // little hack for last parameter
                if (strpos($name, '(') === false) {
                        $name = rtrim($name, ')');
                }

                if (empty($vars[$name][0])) {
                        error("variable not found: '$name'", 3);
                        $ret[][] = '**dummy**';

                } else {
                        $ret[] = array($name, $vars[$name][0] . ($x[1] ? '*' : ''), $vars[$name][1]);
                }

                // the end (yes, this is a little hack :P)
                if ($x[3]) {
                        break;
                }
        }

//      if ($GLOBALS['current_function'] == 'for_debugging') { var_dump($m); var_dump($ret); }
        return $ret;
}


/** run tests on a function. the code is passed in $txt */
function check_function($name, $txt, $offset)
{
        global $API_params;

        if (preg_match_all('/zend_parse_parameters(?:_ex\s*\([^,]+,[^,]+|\s*\([^,]+),\s*"([^"]*)"\s*,\s*([^{;]*)/S', $txt, $matches, PREG_SET_ORDER | PREG_OFFSET_CAPTURE)) {

                $GLOBALS['current_function'] = $name;

                foreach ($matches as $m) {
                        $GLOBALS['error_few_vars_given'] = false;
                        update_lineno($offset + $m[2][1]);

                        $vars = get_vars(substr($txt, 0, $m[0][1])); // limit var search to current location
                        $params = get_params($vars, $m[2][0]);
                        $optional = $varargs = false;
                        $last_last_char = $last_char = '';
                        $j = -1;
                        $len = strlen($m[1][0]);

                        for ($i = 0; $i < $len; ++$i) {
                                switch($char = $m[1][0][$i]) {
                                        // separator for optional parameters
                                        case '|':
                                                if ($optional) {
                                                        error("more than one optional separator at char #$i");
                                                } else {
                                                        $optional = true;
                                                        if ($i == $len-1) {
                                                                error("unnecessary optional separator");
                                                        }
                                                }
                                        break;

                                        // separate_zval_if_not_ref
                                        case '/':
                                                if (!in_array($last_char, array('r', 'z'))) {
                                                        error("the '/' specifier cannot be applied to '$last_char'");
                                                }
                                        break;

                                        // nullable arguments
                                        case '!':
                                                if (!in_array($last_char, array('a', 'C', 'f', 'h', 'o', 'O', 'r', 's', 't', 'z', 'Z'))) {
                                                        error("the '!' specifier cannot be applied to '$last_char'");
                                                }
                                        break;

                                        case '&':
                                                if (version_compare(VERSION, '6', 'ge')) {
                                                        if ($last_char == 's' || ($last_last_char == 's' && $last_char == '!')) {
                                                                check_param($params, ++$j, 'UConverter*', $optional);

                                                        } else {
                                                                error("the '&' specifier cannot be applied to '$last_char'");
                                                        }
                                                } else {
                                                        error("unknown char ('&') at column $i");
                                                }
                                        break;

                                        case '+':
                                        case '*':
                                                if (version_compare(VERSION, '6', 'ge')) {
                                                        if ($varargs) {
                                                                error("A varargs specifier can only be used once. repeated char at column $i");
                                                        } else {
                                                                check_param($params, ++$j, 'zval****', $optional);
                                                                check_param($params, ++$j, 'int*', $optional);
                                                                $varargs = true;
                                                        }
                                                } else {
                                                        error("unknown char ('$char') at column $i");
                                                }
                                        break;

                                        default:
                                                if (isset($API_params[$char])) {
                                                        foreach($API_params[$char] as $exp) {
                                                                check_param($params, ++$j, $exp, $optional);
                                                        }
                                                } else {
                                                        error("unknown char ('$char') at column $i");
                                                }
                                }

                                $last_last_char = $last_char;
                                $last_char = $char;
                        }
                }
        }
}


/** the main recursion function. splits files in functions and calls the other functions */
function recurse($path)
{
        foreach (scandir($path) as $file) {
                if ($file == '.' || $file == '..' || $file == 'CVS') continue;

                $file = "$path/$file";
                if (is_dir($file)) {
                        recurse($file);
                        continue;
                }

                // parse only .c and .cpp files
                if (substr_compare($file, '.c', -2) && substr_compare($file, '.cpp', -4)) continue;

                $txt = file_get_contents($file);
                // remove comments (but preserve the number of lines)
                $txt = preg_replace(array('@//.*@S', '@/\*.*\*/@SsUe'), array('', 'preg_replace("/[^\r\n]+/S", "", \'$0\')'), $txt);


                $split = preg_split('/PHP_(?:NAMED_)?(?:FUNCTION|METHOD)\s*\((\w+(?:,\s*\w+)?)\)/S', $txt, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_OFFSET_CAPTURE);

                if (count($split) < 2) continue; // no functions defined on this file
                array_shift($split); // the first part isn't relevant


                // generate the line offsets array
                $j = 0;
                $lines = preg_split("/(\r\n?|\n)/S", $txt, -1, PREG_SPLIT_DELIM_CAPTURE);
                $lines_offset = array();

                for ($i = 0; $i < count($lines); ++$i) {
                        $j += strlen($lines[$i]) + strlen(@$lines[++$i]);
                        $lines_offset[] = $j;
                }

                $GLOBALS['lines_offset'] = $lines_offset;
                $GLOBALS['current_file'] = $file;


                for ($i = 0; $i < count($split); $i+=2) {
                        // if the /* }}} */ comment is found use it to reduce false positives
                        // TODO: check the other indexes
                        list($f) = preg_split('@/\*\s*}}}\s*\*/@S', $split[$i+1][0]);
                        check_function(preg_replace('/\s*,\s*/S', '::', $split[$i][0]), $f, $split[$i][1]);
                }
        }
}

$dirs = array();

if (isset($argc) && $argc > 1) {
        if ($argv[1] == '-h' || $argv[1] == '-help' || $argv[1] == '--help') {
                echo <<<HELP
Synopsis:
    php check_parameters.php [directories]

HELP;
                exit(0);
        }
        for ($i = 1; $i < $argc; $i++) {
                $dirs[] = $argv[$i];
        }
} else { 
        $dirs[] = PHPDIR;
}

foreach($dirs as $dir) {
        if (is_dir($dir)) {
                if (!is_readable($dir)) {
                        echo "ERROR: directory '", $dir ,"' is not readable\n";
                        exit(1);
                }
        } else {
                echo "ERROR: bogus directory '", $dir ,"'\n";
                exit(1);
        }
}

foreach ($dirs as $dir) {
        recurse(realpath($dir));
}

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