From ba387e0c47007d6ab7e577ce890b6d7b48b4714f Mon Sep 17 00:00:00 2001
From: Piotr KUCHARSKI <bif.github@42.pl>
Date: Wed, 26 Nov 2014 22:43:51 +0100
Subject: [PATCH] if rss script is in read-only directory, skip file generation
 and diff calculations.

---
 rss.php | 96 ++++++++++++++++++++++++++++++---------------------------
 1 file changed, 51 insertions(+), 45 deletions(-)

diff --git a/rss.php b/rss.php
index 2fa71d8..a3083cc 100644
--- a/rss.php
+++ b/rss.php
@@ -92,61 +92,67 @@ function print_array($array_to_display)
 /*===================*/
 require("config-default.php");
 include("config.php");
-#$content = "";
-$old_files_list = "db_old_files"; //list of files in ./photos
-$db_feed_source = "db_feed_source";
-$db_rss_timestamp = "db_rss_timestamp";
-$Folder = 'photos';
-$content = ListFiles($gallery_link, $content, $Folder, $SkipExts, $SkipObjects);
-$to_store = "";
-// Init files
-if (!file_exists($old_files_list)) {
-    file_put_contents($old_files_list, "");
-}
-if (!file_exists($db_feed_source)) {
-    file_put_contents($db_feed_source, "");
-}
-if (!file_exists($db_rss_timestamp)) {
-    file_put_contents($db_rss_timestamp, "");
-}
 
-/*===================*/
-/* Computing         */
-/*===================*/
-#Todo : ajouter une condition : dois-je regénérer le flux ou utiliser les anciens fichiers ?
-$temp = file_get_contents($db_feed_source);
-$last_rss_gen = file_get_contents($db_rss_timestamp);
-$current_time = time();
-// If the RSS generation is already launched, don't do a second generation at the same time
-if (($current_time - $last_rss_gen) > $rss_refresh_interval && file_exists("rss.locker") == false) {
-    file_put_contents("rss.locker", "");
-    file_put_contents($db_rss_timestamp, time());
-    // Load the list from files.
-    $old_files_list_content = explode("\n", file_get_contents($old_files_list));
-    $new_files_list_content = explode("\n", $content); #debug 
-    // Generate and stock new elements
-    $differences = diff($old_files_list_content, $new_files_list_content);
-    for ($i=0; $i < count($differences); $i++) {
-        if (is_array($differences[$i])) {
-            for ($j=0; $j < count($differences[$i]["i"]); $j++) {
-                if (strlen($differences[$i]["i"][$j]) > 2) {
-                    $to_store .= $differences[$i]["i"][$j] . "\n";
+$content = "";
+$folder = "photos";
+$content = listFiles($gallery_link, $content, $folder, $SkipExts, $SkipObjects);
+
+if (is_writeable(".")) {
+    $to_store = "";
+    $old_files_list  = "db_old_files"; //list of files in ./photos
+    $db_feed_source = "db_feed_source";
+    $db_rss_timestamp = "db_rss_timestamp";
+
+    // Init files
+    if (!file_exists($old_files_list)) {
+        file_put_contents($old_files_list, "");
+    }
+    if (!file_exists($db_feed_source)) {
+        file_put_contents($db_feed_source, "");
+    }
+    if (!file_exists($db_rss_timestamp)) {
+        file_put_contents($db_rss_timestamp, "");
+    }
+
+    /*===================*/
+    /* Computing         */
+    /*===================*/
+    #Todo : ajouter une condition : dois-je regénérer le flux ou utiliser les anciens fichiers ?
+    $temp = file_get_contents($db_feed_source);
+    $last_rss_gen = file_get_contents($db_rss_timestamp);
+    $current_time = time();
+    // If the RSS generation is already launched, don't do a second generation at the same time
+    if (($current_time - $last_rss_gen) > $rss_refresh_interval && file_exists("rss.locker") == false) {
+        file_put_contents("rss.locker", "");
+        file_put_contents($db_rss_timestamp, time());
+        // Load the list from files.
+        $old_files_list_content = explode("\n", file_get_contents($old_files_list));
+        $new_files_list_content = explode("\n", $content); #debug
+        // Generate and stock new elements
+        $differences = diff($old_files_list_content, $new_files_list_content);
+        for ($i=0; $i < count($differences); $i++) {
+            if (is_array($differences[$i])) {
+                for ($j=0; $j < count($differences[$i]["i"]); $j++) {
+                    if (strlen($differences[$i]["i"][$j]) > 2) {
+                        $to_store .= $differences[$i]["i"][$j] . "\n";
+                    }
                 }
             }
         }
+        // Add new elements at the top of the feed's source
+        $temp = $to_store . $temp;
+        file_put_contents($db_feed_source, $temp);
+        // Store the current file list for the next generation
+        file_put_contents($old_files_list, $content);
+        unlink("rss.locker");
     }
-    // Add new elements at the top of the feed's source
-    $temp = $to_store . $temp;
-    file_put_contents($db_feed_source, $temp);
-    // Store the current file list for the next generation
-    file_put_contents($old_files_list, $content);
-    unlink("rss.locker");
+    $content = $temp;
 }
 
 /*===================*/
 /* XML Gen           */
 /*===================*/
-$temp = explode("\n", $temp);
+$temp = explode("\n", $content);
 echo "<rss version='2.0'>\n<channel>";
 echo "<title>$title</title>";
 echo "<link>$gallery_link</link>";