From f0bd8e6531756b151c051f8ce5099d59408e71db Mon Sep 17 00:00:00 2001
From: Andrew Dolgov <fox@madoka.volgo-balt.ru>
Date: Tue, 19 Mar 2013 09:25:36 +0400
Subject: [PATCH] rework image caching to work without permanent article
 content rewriting (refs #582)

---
 image.php             | 35 ++++++++++++++++++++++++++++-------
 include/functions.php | 15 +++++++++++----
 include/rssfuncs.php  |  2 +-
 3 files changed, 40 insertions(+), 12 deletions(-)

diff --git a/image.php b/image.php
index 91490ea2..cccda64b 100644
--- a/image.php
+++ b/image.php
@@ -4,14 +4,35 @@
 
 	require_once "config.php";
 
-	$url = base64_decode($_GET['url']);
+	// backwards compatible wrapper for old-style image caching
+	/* if (isset($_GET['url'])) {
+		$url = base64_decode($_GET['url']);
 
-	$filename = CACHE_DIR . '/images/' . sha1($url) . '.png';
+		$filename = CACHE_DIR . '/images/' . sha1($url) . '.png';
 
-	if (file_exists($filename)) {
-		header("Content-type: image/png");
-		echo file_get_contents($filename);
-	} else {
-		header("Location: $url");
+		if (file_exists($filename)) {
+			header("Content-type: image/png");
+			echo file_get_contents($filename);
+		} else {
+			header("Location: $url");
+		}
+
+		return;
+	} */
+
+	@$hash = basename($_GET['hash']);
+
+	if ($hash) {
+
+		$filename = CACHE_DIR . '/images/' . $hash . '.png';
+
+		if (file_exists($filename)) {
+			header("Content-type: image/png");
+			echo file_get_contents($filename);
+		} else {
+			header($_SERVER["SERVER_PROTOCOL"]." 404 Not Found");
+			echo "File not found.";
+		}
 	}
+
 ?>
diff --git a/include/functions.php b/include/functions.php
index 43a9270e..a7ac07b5 100644
--- a/include/functions.php
+++ b/include/functions.php
@@ -2590,10 +2590,17 @@
 					$entry->setAttribute('href',
 						rewrite_relative_url($site_url, $entry->getAttribute('href')));
 
-				if ($entry->hasAttribute('src'))
-					if (preg_match('/^image.php\?i=[a-z0-9]+$/', $entry->getAttribute('src')) == 0)
-						$entry->setAttribute('src',
-							rewrite_relative_url($site_url, $entry->getAttribute('src')));
+				if ($entry->hasAttribute('src')) {
+					$src = rewrite_relative_url($site_url, $entry->getAttribute('src'));
+
+					$cached_filename = CACHE_DIR . '/images/' . sha1($src) . '.png';
+
+					if (file_exists($cached_filename)) {
+						$src = SELF_URL_PATH . '/image.php?hash=' . sha1($src);
+					}
+
+					$entry->setAttribute('src', $src);
+				}
 			}
 
 			if (strtolower($entry->nodeName) == "a") {
diff --git a/include/rssfuncs.php b/include/rssfuncs.php
index 1180b0ad..df1d1698 100644
--- a/include/rssfuncs.php
+++ b/include/rssfuncs.php
@@ -581,7 +581,7 @@
 				}
 
 				if ($cache_images && is_writable(CACHE_DIR . '/images'))
-					$entry_content = cache_images($entry_content, $site_url, $debug_enabled);
+					cache_images($entry_content, $site_url, $debug_enabled);
 
 				$entry_content = db_escape_string($entry_content, false);
 
-- 
2.39.5