From 7f000f86812f83c12e785a0f6092ee08337c663f Mon Sep 17 00:00:00 2001
From: Timo Tijhof <krinklemail@gmail.com>
Date: Mon, 24 Jul 2017 22:11:17 -0700
Subject: [PATCH] Re-introduce use of mime_content_type()

Follows-up eac059c7224. See also https://stackoverflow.com/a/39676272/319266.

This function was never deprecated. For a short time, the www.php.net
manual page for `mime_content_type` wrongly documented it as having been
deprecated in PHP 5.3, but this wasn't true, and it has been present in
every PHP version since PHP 4.3, including PHP 7 and HHVM 2.3+.

Between PHP 4.3.0-4.3.2 and PHP 5.0-5.3, the function would be absent
if the Mimemagic extension was not enabled at compile-time. However, while
mime_content_type was first introduced by the Mimemagic PHP ext, it is
backend by the Finfo extension since PHP 5.3.0.

Confirmed via https://3v4l.org/IQC1Q.

* CSSMin: Revert conditional use of finfo back to unconditional use
  of mime_content_type.

* MimeAnalyzer: Replace conditional use of finfo with unconditional use
  use of mime_content_type. Also remove the now-redundant 'else' branch.
  The 'else' branch existed because this code was written at a time where
  MediaWiki still supported PHP 4, of which some minor versions could
  sometimes be compiled without this function.

Change-Id: Iee4a0b6f616a469bb779c40e386045f9c3200446
---
 includes/DefaultSettings.php                   |  2 +-
 includes/libs/CSSMin.php                       | 12 +-----------
 includes/libs/filebackend/FileBackendStore.php | 10 ++--------
 includes/libs/mime/MimeAnalyzer.php            | 12 +-----------
 4 files changed, 5 insertions(+), 31 deletions(-)

diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index f35715e8be..74d5fa4471 100644
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -1304,7 +1304,7 @@ $wgMimeInfoFile = 'includes/mime.info';
  * Sets an external MIME detector program. The command must print only
  * the MIME type to standard output.
  * The name of the file to process will be appended to the command given here.
- * If not set or NULL, PHP's fileinfo extension will be used if available.
+ * If not set or NULL, PHP's mime_content_type function will be used.
  *
  * @par Example:
  * @code
diff --git a/includes/libs/CSSMin.php b/includes/libs/CSSMin.php
index 9e060cd54a..4c672f4644 100644
--- a/includes/libs/CSSMin.php
+++ b/includes/libs/CSSMin.php
@@ -188,17 +188,7 @@ class CSSMin {
 			return self::$mimeTypes[$ext];
 		}
 
-		$realpath = realpath( $file );
-		if (
-			$realpath
-			&& function_exists( 'finfo_file' )
-			&& function_exists( 'finfo_open' )
-			&& defined( 'FILEINFO_MIME_TYPE' )
-		) {
-			return finfo_file( finfo_open( FILEINFO_MIME_TYPE ), $realpath );
-		}
-
-		return false;
+		return mime_content_type( realpath( $file ) );
 	}
 
 	/**
diff --git a/includes/libs/filebackend/FileBackendStore.php b/includes/libs/filebackend/FileBackendStore.php
index 9bfdbe8cd6..77473d139c 100644
--- a/includes/libs/filebackend/FileBackendStore.php
+++ b/includes/libs/filebackend/FileBackendStore.php
@@ -1840,14 +1840,8 @@ abstract class FileBackendStore extends FileBackend {
 			return call_user_func_array( $this->mimeCallback, func_get_args() );
 		}
 
-		$mime = null;
-		if ( $fsPath !== null && function_exists( 'finfo_file' ) ) {
-			$finfo = finfo_open( FILEINFO_MIME_TYPE );
-			$mime = finfo_file( $finfo, $fsPath );
-			finfo_close( $finfo );
-		}
-
-		return is_string( $mime ) ? $mime : 'unknown/unknown';
+		$mime = ( $fsPath !== null ) ? mime_content_type( $fsPath ) : false;
+		return $mime ?: 'unknown/unknown';
 	}
 }
 
diff --git a/includes/libs/mime/MimeAnalyzer.php b/includes/libs/mime/MimeAnalyzer.php
index 631bb17ebf..4d860bb593 100644
--- a/includes/libs/mime/MimeAnalyzer.php
+++ b/includes/libs/mime/MimeAnalyzer.php
@@ -988,18 +988,8 @@ EOT;
 		$m = null;
 		if ( $callback ) {
 			$m = $callback( $file );
-		} elseif ( function_exists( "finfo_open" ) && function_exists( "finfo_file" ) ) {
-			$mime_magic_resource = finfo_open( FILEINFO_MIME );
-
-			if ( $mime_magic_resource ) {
-				$m = finfo_file( $mime_magic_resource, $file );
-				finfo_close( $mime_magic_resource );
-			} else {
-				$this->logger->info( __METHOD__ .
-					": finfo_open failed on " . FILEINFO_MIME . "!\n" );
-			}
 		} else {
-			$this->logger->info( __METHOD__ . ": no magic mime detector found!\n" );
+			$m = mime_content_type( $file );
 		}
 
 		if ( $m ) {
-- 
2.20.1