#20070 [Opn->]: PHPDoc unrestrained recursion seg. faults php

ID: 20070 Updated by: iliaa@php.net Reported By: mattb@columbia.edu -Status: Open +Status: Won\'t fix Bug Type: PEAR related Operating System: GNU/Linux 2.4.18-17.7.x (RedHat) PHP Version: 4.2.3 New Comment: Unrestrained resucrsion such as: function a() { a(); } a(); will always core until PHP implements it's own stack, which is unlikely to ever happen. Therefor, you should either, not use recursive functions or harcode some sort of a recurssion limit if you are not certain about the maximum possible number of recursions. Previous Comments: ------------------------------------------------------------------------ [2002-10-24 13:39:52] mattb@columbia.edu I've created a class whose comments seems to cause PHP to seg. fault when running PHPDoc. I've attached the file which causes the seg. fault as well as the output from "php -i". Here are the PEAR files I have installed: % pear list-installed Installed packages: =================== +---------+---------+--------+ | Package | Version | State | | PHPDoc | 0.1.0 | beta | | PHPUnit | 0.4 | stable | +---------+---------+--------+ Here is the command I use to run phpdoc: % ls -a ~/php . .. Base.php % rm -fr /tmp/phpdoc ; phpdoc -s ~/php -d /tmp/phpdoc \ -t $PHP_HOME/share/pear/PHPDoc zsh: segmentation fault phpdoc ... I don't have debugging symbols compiled into my version of PHP, but GDB shows would looks like unrestrained recursion happening: (no debugging symbols found)... Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 1024 (LWP 1114)] 0x080b06ef in ?? () (gdb) bt #0 0x080b06ef in ?? () #1 0x080af0cc in ?? () #2 0x080af9e1 in ?? () #3 0x080af0cc in ?? () #4 0x080af9e1 in ?? () #5 0x080af0cc in ?? () #6 0x080af9e1 in ?? () #7 0x080af0cc in ?? () #8 0x080af9e1 in ?? () #9 0x080af0cc in ?? () #10 0x080af9e1 in ?? () #11 0x080af0cc in ?? () #12 0x080af9e1 in ?? () ... #8513 0x080af0cc in ?? () #8514 0x080af9e1 in ?? () #8515 0x080af0cc in ?? () #8516 0x080af9e1 in ?? () #8517 0x080af0cc in ?? () #8518 0x080af008 in ?? () #8519 0x080af008 in ?? () #8520 0x080b1903 in ?? () #8521 0x080b1903 in ?? () #8522 0x080b1903 in ?? () #8523 0x080af0cc in ?? () #8524 0x080b1f74 in ?? () #8525 0x080a77a6 in ?? () #8526 0x080a7b6c in ?? () #8527 0x0815710b in ?? () #8528 0x081572df in ?? () #8529 0x081572df in ?? () #8530 0x081572df in ?? () #8531 0x081572df in ?? () #8532 0x0812ddee in ?? () #8533 0x08067fb2 in ?? () #8534 0x08065574 in ?? () #8535 0x404ae1c4 in __libc_start_main () from /lib/libc.so.6 I'll try and paste the file here, but feel free to e-mail me for the actual file (and the output from strace): <?php // Protected global constants //======================================================================== /** * the prefix of all vars which hold field values * @const _ARENA_DATA_BASE_FIELD_PREFIX */ define('_ARENA_DATA_BASE_FIELD_PREFIX', '__field_'); //======================================================================== /** * the string length of _ARENA_DATA_BASE_FIELD_PREFIX * @const _ARENA_DATA_BASE_FIELD_PREFIX_LEN */ define('_ARENA_DATA_BASE_FIELD_PREFIX_LEN', strlen(_ARENA_DATA_BASE_FIELD_PREFIX)); //======================================================================== /** * Base class to represent a row in a table. * * Copyright (c) 2002 <a href="http://arenaunlimited.com/">Arena * Unlimited, Inc.</a> All rights reserved. * * Reproduction, distribution, use, and/or modification of this software * is strictly prohibitted without express written consent from Arena * Unlimited, Inc. * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * @author Matthew Bogosian <matt@arenaunlimited.com> * @package arena::data * @version $Id: Arena_Base.php,v 1.1 2002/10/08 07:37:14 matt Exp $ */ class Arena_Data_Base { // Constructor //======================================================================== /** * Class constructor. * * @param PEAR_DB &$a_Connection the PEAR_DB connection object * @access public */ function Arena_Data_Base(&$a_Connection) { $__connection = &$a_Connection; } // Public methods //======================================================================== /** * Returns the PEAR_DB connection associated with this database object. * * @return object PEAR_DB the connection associated with this database * object * @access public */ function &getConnection() { return $__connection; } // Protected hook methods //======================================================================== /** * Returns the names of the fields associated with this database object. * This hook function may be overridden by subclasses. However, there is * no need for subclasses to override this function if the subclass has a * declared var for each of its corresponding table fields named: * <code> * _ARENA_DATA_BASE_FIELD_PREFIX . [FIELD_NAME] * </code> * (Where [FIELD_NAME] is the name of the field.) Since vars are more * strict than variable declarations, this must be done by declaring vars * with fixed names in the subclass in the following manner: * <code> * var $__field_[FIELD_NAME]; * </code> * Note: in versions up to and including PHP4, the following will not * work: * <code> * // Not allowed by PHP * var ${_ARENA_DATA_BASE_FIELD_PREFIX . [FIELD_NAME]}; * </code> * Here's an example for three fields named, 'id', 'full_name' and * 'has_the_clap': * <code> * var $__field_id; * var $__field_full_name; * var $__field_has_the_clap; * </code> * Alternatively, if you're all right with losing some introspection * functionality on your subclasses, you can get rid of the var * declarations altogether and do something like the following in your * constructor: * <code> * $this->{_ARENA_DATA_BASE_FIELD_PREFIX . [FIELD_NAME]} = null; * </code> * This will allow you to use the constant notation without hard-coding * '__field_' everywhere. This function uses instance inspection to build * the list of field names so even a combination of both techniques is * acceptable. However, keep in mind that if it's not a var, and you unset * it, this function will lose visibility into it: * <code> * // This may have side effects; set it to null instead * unset($this->{_ARENA_DATA_BASE_FIELD_PREFIX . [FIELD_NAME]}); * </code> * The array that is returned from the function is an array of the * following format: * <code> * array * ( * [FIELD_NAME] => [FIELD_NAME], ... * ); * </code> * Note that the field name is both the key and the value. This is * intended to enable maximum flexibility by easing the complexity of * subclasses that wish to extend this method while retaining the ability * to use the resulting array in a foreach loop: * <code> * class SubClass extends Arena_Data_Base * { * ... * function &_getFieldNames() * { * $myFieldNames = array(...); * return array_merge(parent::_getFieldNames(), $myFieldNames); * } * } * ... * foreach ($mySubClass->_getFieldNames() as $fieldName) {...} * </code> * In order for this to work, all subclasses must also follow the * [FIELD_NAME] => [FIELD_NAME] convention. * * @return array the names of the fields associated with this database * object * @access protected */ function &_getFieldNames() { // Get the instance variables $varNames = array_keys((array)($this)); $fieldNames = array(); // Figure out which names match foreach ($varNames as $varName) { if (strncasecmp(_ARENA_DATA_BASE_FIELD_PREFIX, $varName, _ARENA_DATA_BASE_FIELD_PREFIX_LEN) == 0 && strlen($varName) > _ARENA_DATA_BASE_FIELD_PREFIX_LEN) { $fieldName = substr($varName, _ARENA_DATA_BASE_FIELD_PREFIX_LEN); $fieldNames[$fieldName] = $fieldName; } } return $fieldNames; } //======================================================================== /** * Returns the table name associated with this database object. * * @return string the table name associated with this database object * @access protected */ function &_getTableName() { return ''; } //======================================================================== /** * Returns the field names which make up the primary key of this database * object. The return from this function has the same format as * Arena_Data_Base::_getFieldNames(). * * @return array the field names which make up the primary key of this * database object * @access protected * @see Arena_Data_Base::_getFieldNames() */ function &_getPrimaryKey() { return _getFieldNames(); } // Private data members //======================================================================== /** * the database connection * * @var object PEAR_DB * @access private */ var $__connection; } ?> ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=20070&edit=1