<?php /* Question2Answer (c) Gideon Greenspan http://www.question2answer.org/ File: qa-include/qa-app-blobs.php Version: See define()s at top of qa-include/qa-base.php Description: Application-level blob-management functions This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. More about this license: http://www.question2answer.org/license.php */ if (!defined('QA_VERSION')) { // don't allow this page to be requested directly from browser header('Location: ../'); exit; } function qa_get_blob_url($blobid, $absolute=false) /* Return the URL which will output $blobid from the database when requested, $absolute or relative */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } return qa_path('blob', array('qa_blobid' => $blobid), $absolute ? qa_opt('site_url') : null, QA_URL_FORMAT_PARAMS); } function qa_get_blob_directory($blobid) /* Return the full path to the on-disk directory for blob $blobid (subdirectories are named by the first 3 digits of $blobid) */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } return rtrim(QA_BLOBS_DIRECTORY, '/').'/'.substr(str_pad($blobid, 20, '0', STR_PAD_LEFT), 0, 3); } function qa_get_blob_filename($blobid, $format) /* Return the full page and filename of blob $blobid which is in $format ($format is used as the file name suffix e.g. .jpg) */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } return qa_get_blob_directory($blobid).'/'.$blobid.'.'.preg_replace('/[^A-Za-z0-9]/', '', $format); } function qa_create_blob($content, $format, $sourcefilename=null, $userid=null, $cookieid=null, $ip=null) /* Create a new blob (storing the content in the database or on disk as appropriate) with $content and $format, returning its blobid. Pass the original name of the file uploaded in $sourcefilename and the $userid, $cookieid and $ip of the user creating it */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } require_once QA_INCLUDE_DIR.'qa-db-blobs.php'; $blobid=qa_db_blob_create(defined('QA_BLOBS_DIRECTORY') ? null : $content, $format, $sourcefilename, $userid, $cookieid, $ip); if (isset($blobid) && defined('QA_BLOBS_DIRECTORY')) if (!qa_write_blob_file($blobid, $content, $format)) qa_db_blob_set_content($blobid, $content); // still write content to the database if writing to disk failed return $blobid; } function qa_write_blob_file($blobid, $content, $format) /* Write the on-disk file for blob $blobid with $content and $format. Returns true if the write succeeded, false otherwise. */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } $written=false; $directory=qa_get_blob_directory($blobid); if (is_dir($directory) || mkdir($directory, fileperms(rtrim(QA_BLOBS_DIRECTORY, '/')) & 0777)) { $filename=qa_get_blob_filename($blobid, $format); $file=fopen($filename, 'xb'); if (is_resource($file)) { if (fwrite($file, $content)>=strlen($content)) $written=true; fclose($file); if (!$written) unlink($filename); } } return $written; } function qa_read_blob($blobid) /* Retrieve blob $blobid from the database, reading the content from disk if appropriate */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } require_once QA_INCLUDE_DIR.'qa-db-blobs.php'; $blob=qa_db_blob_read($blobid); if (defined('QA_BLOBS_DIRECTORY') && !isset($blob['content'])) $blob['content']=qa_read_blob_file($blobid, $blob['format']); return $blob; } function qa_read_blob_file($blobid, $format) /* Read the content of blob $blobid in $format from disk. On failure, it will return false. */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } return file_get_contents(qa_get_blob_filename($blobid, $format)); } function qa_delete_blob($blobid) /* Delete blob $blobid from the database, and remove the on-disk file if appropriate */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } require_once QA_INCLUDE_DIR.'qa-db-blobs.php'; if (defined('QA_BLOBS_DIRECTORY')) { $blob=qa_db_blob_read($blobid); if (isset($blob) && !isset($blob['content'])) unlink(qa_get_blob_filename($blobid, $blob['format'])); } qa_db_blob_delete($blobid); } function qa_delete_blob_file($blobid, $format) /* Delete the on-disk file for blob $blobid in $format */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } unlink(qa_get_blob_filename($blobid, $format)); } function qa_blob_exists($blobid) /* Check if blob $blobid exists */ { if (qa_to_override(__FUNCTION__)) { $args=func_get_args(); return qa_call_override(__FUNCTION__, $args); } require_once QA_INCLUDE_DIR.'qa-db-blobs.php'; return qa_db_blob_exists($blobid); } /* Omit PHP closing tag to help avoid accidental output */