Example patch to add a new field ("via") for links, an input field to set the "via" property from the "edit link" dialog, and display the "via" field in the link list display. Untested, use at your own risk

Thanks to @Knah-Tsaeb in https://github.com/sebsauvage/Shaarli/pull/158

From e0f363c18e8fe67990ed2bb1a08652e24e70bbcb Mon Sep 17 00:00:00 2001
From: Knah Tsaeb <knah-tsaeb@knah-tsaeb.org>
Date: Fri, 11 Oct 2013 15:18:37 +0200
Subject: [PATCH] Add a "via"/origin property for links, add new input in "edit link" dialog
Thanks to:
* https://github.com/Knah-Tsaeb/Shaarli/commit/040eb18ec8cdabd5ea855e108f81f97fbf0478c4
* https://github.com/Knah-Tsaeb/Shaarli/commit/4123658eae44d7564d1128ce52ddd5689efee813
* https://github.com/Knah-Tsaeb/Shaarli/commit/f1a8ca9cc8fe49b119d51b2d8382cc1a34542f96

---
 index.php         | 43 ++++++++++++++++++++++++++++++++-----------
 tpl/editlink.html |  1 +
 tpl/linklist.html |  1 +
 3 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/index.php b/index.php
index 6fae2f8..53f798e 100644
--- a/index.php
+++ b/index.php
@@ -436,6 +436,12 @@ if (isset($_POST['login']))
 // ------------------------------------------------------------------------------------------
 // Misc utility functions:
 
+// Try to get just domain for @via
+function getJustDomain($url){
+    $parts = parse_url($url);   
+    return trim($parts['host']);
+    }
+
 // Returns the server URL (including port and http/https), without path.
 // e.g. "http://myserver.com:8080"
 // You can append $_SERVER['SCRIPT_NAME'] to get the current script URL.
@@ -799,7 +805,8 @@ class linkdb implements Iterator, Countable, ArrayAccess
             $found=   (strpos(strtolower($l['title']),$s)!==false)
                    || (strpos(strtolower($l['description']),$s)!==false)
                    || (strpos(strtolower($l['url']),$s)!==false)
-                   || (strpos(strtolower($l['tags']),$s)!==false);
+                   || (strpos(strtolower($l['tags']),$s)!==false)
+                   || (!empty($l['via']) && (strpos(strtolower($l['via']),$s)!==false));
             if ($found) $filtered[$l['linkdate']] = $l;
         }
         krsort($filtered);
@@ -814,7 +821,7 @@ class linkdb implements Iterator, Countable, ArrayAccess
         $t = str_replace(',',' ',($casesensitive?$tags:strtolower($tags)));
         $searchtags=explode(' ',$t);
         $filtered=array();
-        foreach($this->links as $l)
+        foreach($this-> links as $l)
         {
             $linktags = explode(' ',($casesensitive?$l['tags']:strtolower($l['tags'])));
             if (count(array_intersect($linktags,$searchtags)) == count($searchtags))
@@ -905,7 +912,7 @@ function showRSS()
     else $linksToDisplay = $LINKSDB;
     $nblinksToDisplay = 50;  // Number of links to display.
     if (!empty($_GET['nb']))  // In URL, you can specificy the number of links. Example: nb=200 or nb=all for all links.
-    { 
+    {
         $nblinksToDisplay = $_GET['nb']=='all' ? count($linksToDisplay) : max($_GET['nb']+0,1) ;
     }
 
@@ -944,7 +951,12 @@ function showRSS()
         // If user wants permalinks first, put the final link in description
         if ($usepermalinks===true) $descriptionlink = '(<a href="'.$absurl.'">Link</a>)';
         if (strlen($link['description'])>0) $descriptionlink = '<br>'.$descriptionlink;
-        echo '<description><![CDATA['.nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))).$descriptionlink.']]></description>'."\n</item>\n";
+        if(!empty($link['via'])){
+          $via = '<br>Origine => <a href="'.htmlspecialchars($link['via']).'">'.htmlspecialchars(getJustDomain($link['via'])).'</a>';
+        } else {
+         $via = '';
+        }
+        echo '<description><![CDATA['.nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))).$via.$descriptionlink.']]></description>'."\n</item>\n";
         $i++;
     }
     echo '</channel></rss><!-- Cached version of '.htmlspecialchars(pageUrl()).' -->';
@@ -980,7 +992,7 @@ function showATOM()
     else $linksToDisplay = $LINKSDB;
     $nblinksToDisplay = 50;  // Number of links to display.
     if (!empty($_GET['nb']))  // In URL, you can specificy the number of links. Example: nb=200 or nb=all for all links.
-    { 
+    {
         $nblinksToDisplay = $_GET['nb']=='all' ? count($linksToDisplay) : max($_GET['nb']+0,1) ;
     }
 
@@ -1006,11 +1018,16 @@ function showATOM()
 
         // Add permalink in description
         $descriptionlink = htmlspecialchars('(<a href="'.$guid.'">Permalink</a>)');
+        if(isset($link['via']) && !empty($link['via'])){
+          $via = htmlspecialchars('</br> Origine => <a href="'.$link['via'].'">'.getJustDomain($link['via']).'</a>');
+        } else {
+          $via = '';
+        }
         // If user wants permalinks first, put the final link in description
         if ($usepermalinks===true) $descriptionlink = htmlspecialchars('(<a href="'.$absurl.'">Link</a>)');
         if (strlen($link['description'])>0) $descriptionlink = '&lt;br&gt;'.$descriptionlink;
 
-        $entries.='<content type="html">'.htmlspecialchars(nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))))).$descriptionlink."</content>\n";
+        $entries.='<content type="html">'.htmlspecialchars(nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))))).$descriptionlink.$via."</content>\n";
         if ($link['tags']!='') // Adding tags to each ATOM entry (as mentioned in ATOM specification)
         {
             foreach(explode(' ',$link['tags']) as $tag)
@@ -1478,7 +1495,7 @@ function renderPage()
         if (!startsWith($url,'http:') && !startsWith($url,'https:') && !startsWith($url,'ftp:') && !startsWith($url,'magnet:') && !startsWith($url,'?'))
             $url = 'http://'.$url;
         $link = array('title'=>trim($_POST['lf_title']),'url'=>$url,'description'=>trim($_POST['lf_description']),'private'=>(isset($_POST['lf_private']) ? 1 : 0),
-                      'linkdate'=>$linkdate,'tags'=>str_replace(',',' ',$tags));
+                      'linkdate'=>$linkdate,'tags'=>str_replace(',',' ',$tags), 'via'=>trim($_POST['lf_via']));
         if ($link['title']=='') $link['title']=$link['url']; // If title is empty, use the URL as title.
         $LINKSDB[$linkdate] = $link;
         $LINKSDB->savedb(); // Save to disk.
@@ -1556,7 +1573,8 @@ function renderPage()
             $title = (empty($_GET['title']) ? '' : $_GET['title'] ); // Get title if it was provided in URL (by the bookmarklet).
             $description = (empty($_GET['description']) ? '' : $_GET['description']); // Get description if it was provided in URL (by the bookmarklet). [Bronco added that]
             $tags = (empty($_GET['tags']) ? '' : $_GET['tags'] ); // Get tags if it was provided in URL
-            $private = (!empty($_GET['private']) && $_GET['private'] === "1" ? 1 : 0); // Get private if it was provided in URL 
+            $via = (empty($_GET['via']) ? '' : $_GET['via'] );
+            $private = (!empty($_GET['private']) && $_GET['private'] === "1" ? 1 : 0); // Get private if it was provided in URL
             if (($url!='') && parse_url($url,PHP_URL_SCHEME)=='') $url = 'http://'.$url;
             // If this is an HTTP link, we try go get the page to extract the title (otherwise we will to straight to the edit form.)
             if (empty($title) && parse_url($url,PHP_URL_SCHEME)=='http')
@@ -1567,7 +1585,7 @@ function renderPage()
                     {
                         // Look for charset in html header.
                        preg_match('#<meta .*charset=.*>#Usi', $data, $meta);
- 
+
                        // If found, extract encoding.
                        if (!empty($meta[0]))
                        {
@@ -1577,7 +1595,7 @@ function renderPage()
                            $html_charset = (!empty($enc[1])) ? strtolower($enc[1]) : 'utf-8';
                        }
                        else { $html_charset = 'utf-8'; }
- 
+
                        // Extract title
                        $title = html_extract_title($data);
                        if (!empty($title))
@@ -1592,7 +1610,7 @@ function renderPage()
                 $url='?'.smallHash($linkdate);
                 $title='Note: ';
             }
-            $link = array('linkdate'=>$linkdate,'title'=>$title,'url'=>$url,'description'=>$description,'tags'=>$tags,'private'=>$private);
+            $link = array('linkdate'=>$linkdate,'title'=>$title,'url'=>$url,'description'=>$description,'tags'=>$tags,'via' => $via,'private'=>$private);
         }
 
         $PAGE = new pageBuilder;
@@ -1842,6 +1860,9 @@ function buildLinkList($PAGE,$LINKSDB)
         $taglist = explode(' ',$link['tags']);
         uasort($taglist, 'strcasecmp');
         $link['taglist']=$taglist;
+        if(!empty($link['via'])){
+          $link['via']=htmlspecialchars($link['via']);
+        }
         $linkDisp[$keys[$i]] = $link;
         $i++;
     }
diff --git a/tpl/editlink.html b/tpl/editlink.html
index 4a2c30c..14d4f9c 100644
--- a/tpl/editlink.html
+++ b/tpl/editlink.html
@@ -16,6 +16,7 @@
            <i>Title</i><br><input type="text" name="lf_title" value="{$link.title|htmlspecialchars}" style="width:100%"><br>
            <i>Description</i><br><textarea name="lf_description" rows="4" cols="25" style="width:100%">{$link.description|htmlspecialchars}</textarea><br>
            <i>Tags</i><br><input type="text" id="lf_tags" name="lf_tags" value="{$link.tags|htmlspecialchars}" style="width:100%"><br>
+           <i>Origine</i><br><input type="text" name="lf_via" value="{$link.via|htmlspecialchars}" style="width:100%"><br>
            {if condition="($link_is_new && $GLOBALS['privateLinkByDefault']==true) || $link.private == true"}
             <input type="checkbox" checked="checked" name="lf_private" id="lf_private">
             &nbsp;<label for="lf_private"><i>Private</i></label><br>
diff --git a/tpl/linklist.html b/tpl/linklist.html
index ddc38cb..0a8475f 100644
--- a/tpl/linklist.html
+++ b/tpl/linklist.html
@@ -43,6 +43,7 @@
                 <span class="linktitle"><a href="{$redirector}{$value.url|htmlspecialchars}">{$value.title|htmlspecialchars}</a></span>
                 <br>
                 {if="$value.description"}<div class="linkdescription"{if condition="$search_type=='permalink'"} style="max-height:none !important;"{/if}>{$value.description}</div>{/if}
+                {if condition="isset($value.via) && !empty($value.via)"}<div><a href="{$value.via}">Origine => {$value.via|getJustDomain}</a></div>{/if}
                 {if="!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()"}
                     <span class="linkdate" title="Permalink"><a href="?{$value.linkdate|smallHash}">{$value.localdate|htmlspecialchars} - permalink</a> - </span>
                 {else}
-- 
2.1.1