includes/GitInfo.php

   1 <?php
   2 /**
   3  * A class to help return information about a git repo MediaWiki may be inside
   4  * This is used by Special:Version and is also useful for the LocalSettings.php
   5  * of anyone working on large branches in git to setup config that show up only
   6  * when specific branches are currently checked out.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  21  * http://www.gnu.org/copyleft/gpl.html
  22  *
  23  * @file
  24  */
  25
  26 class GitInfo {
  27
  28         /**
  29          * Singleton for the repo at $IP
  30          */
  31         protected static $repo = null;
  32
  33         /**
  34          * Location of the .git directory
  35          */
  36         protected $basedir;
  37
  38         /**
  39          * Map of repo URLs to viewer URLs. Access via static method getViewers().
  40          */
  41         private static $viewers = false;
  42
  43         /**
  44          * @param string $dir The root directory of the repo where the .git dir can be found
  45          */
  46         public function __construct( $dir ) {
  47                 $this->basedir = "{$dir}/.git";
  48                 if ( is_readable( $this->basedir ) && !is_dir( $this->basedir ) ) {
  49                         $GITfile = file_get_contents( $this->basedir );
  50                         if ( strlen( $GITfile ) > 8 && substr( $GITfile, 0, 8 ) === 'gitdir: ' ) {
  51                                 $path = rtrim( substr( $GITfile, 8 ), "\r\n" );
  52                                 $isAbsolute = $path[0] === '/' || substr( $path, 1, 1 ) === ':';
  53                                 $this->basedir = $isAbsolute ? $path : "{$dir}/{$path}";
  54                         }
  55                 }
  56         }
  57
  58         /**
  59          * Return a singleton for the repo at $IP
  60          * @return GitInfo
  61          */
  62         public static function repo() {
  63                 global $IP;
  64                 if ( is_null( self::$repo ) ) {
  65                         self::$repo = new self( $IP );
  66                 }
  67                 return self::$repo;
  68         }
  69
  70         /**
  71          * Check if a string looks like a hex encoded SHA1 hash
  72          *
  73          * @param string $str The string to check
  74          * @return bool Whether or not the string looks like a SHA1
  75          */
  76         public static function isSHA1( $str ) {
  77                 return !!preg_match( '/^[0-9A-F]{40}$/i', $str );
  78         }
  79
  80         /**
  81          * Return the HEAD of the repo (without any opening "ref: ")
  82          * @return string The HEAD
  83          */
  84         public function getHead() {
  85                 $HEADfile = "{$this->basedir}/HEAD";
  86
  87                 if ( !is_readable( $HEADfile ) ) {
  88                         return false;
  89                 }
  90
  91                 $HEAD = file_get_contents( $HEADfile );
  92
  93                 if ( preg_match( "/ref: (.*)/", $HEAD, $m ) ) {
  94                         return rtrim( $m[1] );
  95                 } else {
  96                         return rtrim( $HEAD );
  97                 }
  98         }
  99
 100         /**
 101          * Return the SHA1 for the current HEAD of the repo
 102          * @return string A SHA1 or false
 103          */
 104         public function getHeadSHA1() {
 105                 $HEAD = $this->getHead();
 106
 107                 // If detached HEAD may be a SHA1
 108                 if ( self::isSHA1( $HEAD ) ) {
 109                         return $HEAD;
 110                 }
 111
 112                 // If not a SHA1 it may be a ref:
 113                 $REFfile = "{$this->basedir}/{$HEAD}";
 114                 if ( !is_readable( $REFfile ) ) {
 115                         return false;
 116                 }
 117
 118                 $sha1 = rtrim( file_get_contents( $REFfile ) );
 119
 120                 return $sha1;
 121         }
 122
 123         /**
 124          * Return the name of the current branch, or HEAD if not found
 125          * @return string The branch name, HEAD, or false
 126          */
 127         public function getCurrentBranch() {
 128                 $HEAD = $this->getHead();
 129                 if ( $HEAD && preg_match( "#^refs/heads/(.*)$#", $HEAD, $m ) ) {
 130                         return $m[1];
 131                 } else {
 132                         return $HEAD;
 133                 }
 134         }
 135
 136         /**
 137          * Get an URL to a web viewer link to the HEAD revision.
 138          *
 139          * @return string|bool string if an URL is available or false otherwise.
 140          */
 141         public function getHeadViewUrl() {
 142                 $config = "{$this->basedir}/config";
 143                 if ( !is_readable( $config ) ) {
 144                         return false;
 145                 }
 146
 147                 $configArray = parse_ini_file( $config, true );
 148                 $remote = false;
 149
 150                 // Use the "origin" remote repo if available or any other repo if not.
 151                 if ( isset( $configArray['remote origin'] ) ) {
 152                         $remote = $configArray['remote origin'];
 153                 } else {
 154                         foreach( $configArray as $sectionName => $sectionConf ) {
 155                                 if ( substr( $sectionName, 0, 6 ) == 'remote' ) {
 156                                         $remote = $sectionConf;
 157                                 }
 158                         }
 159                 }
 160
 161                 if ( $remote === false || !isset( $remote['url'] ) ) {
 162                         return false;
 163                 }
 164
 165                 $url = $remote['url'];
 166                 if ( substr( $url, -4 ) !== '.git' ) {
 167                         $url .= '.git';
 168                 }
 169                 foreach( self::getViewers() as $repo => $viewer ) {
 170                         $pattern = '#^' . $repo . '$#';
 171                         if ( preg_match( $pattern, $url ) ) {
 172                                 $viewerUrl = preg_replace( $pattern, $viewer, $url );
 173                                 $headSHA1 = $this->getHeadSHA1();
 174                                 $replacements = array(
 175                                         '%h' => substr( $headSHA1, 0, 7 ),
 176                                         '%H' => $headSHA1
 177                                 );
 178                                 return strtr( $viewerUrl, $replacements );
 179                         }
 180                 }
 181                 return false;
 182         }
 183
 184         /**
 185          * @see self::getHeadSHA1
 186          * @return string
 187          */
 188         public static function headSHA1() {
 189                 return self::repo()->getHeadSHA1();
 190         }
 191
 192         /**
 193          * @see self::getCurrentBranch
 194          * @return string
 195          */
 196         public static function currentBranch() {
 197                 return self::repo()->getCurrentBranch();
 198         }
 199
 200         /**
 201          * @see self::getHeadViewUrl()
 202          * @return bool|string
 203          */
 204         public static function headViewUrl() {
 205                 return self::repo()->getHeadViewUrl();
 206         }
 207
 208         /**
 209          * Gets the list of repository viewers
 210          * @return array
 211          */
 212         protected static function getViewers() {
 213                 global $wgGitRepositoryViewers;
 214
 215                 if( self::$viewers === false ) {
 216                         self::$viewers = $wgGitRepositoryViewers;
 217                         wfRunHooks( 'GitViewers', array( &self::$viewers ) );
 218                 }
 219
 220                 return self::$viewers;
 221         }
 222 }