extcap: Allow loading of extcap files from personal directory

Allow the storage of extcap plugins in the personal directory and
enable loading from there. It will also take precedence of any
system-wide extcaps with an identical name

Change-Id: Ib88e09a26c4f99cf5e793327f2808c7445c6b1b5
Reviewed-on: https://code.wireshark.org/review/34988
Reviewed-by: Roland Knall <rknall@gmail.com>

3 files changed, 28 insertions, 14 deletions

diff --git a/docbook/release-notes.adoc b/docbook/release-notes.adoc
index cd8ac43164..b244bbfbd4 100644
--- a/docbook/release-notes.adoc
+++ b/docbook/release-notes.adoc
@@ -40,6 +40,7 @@ since version 3.1.0:
 * IOGraph automatically adds a graph for the selected display filter if no
   previous graph exists
 * Action buttons for the display filter bar may be aligned left via the context menu
+* Allow extcaps to be loaded from the personal configuration directory
 
 The following features are new (or have been significantly updated)
 since version 3.0.0:
diff --git a/extcap.c b/extcap.c
index fcf3ab8f78..8921915c7a 100644
--- a/extcap.c
+++ b/extcap.c
@@ -219,17 +219,13 @@ extcap_dump_all(void)
     extcap_get_descriptions(print_extcap_description, NULL);
 }
 
-/**
- * Obtains a list of extcap program paths. Use g_slist_free_full(paths, g_free)
- * to destroy the list.
- */
 static GSList *
-extcap_get_extcap_paths(void)
+extcap_get_extcap_paths_from_dir(GSList * list, const char * dirname)
 {
-    GDir *dir;
-    const char *dirname = get_extcap_dir();
-    const gchar *file;
-    GSList *paths = NULL;
+    GDir * dir;
+    const char * file;
+
+    GSList * paths = list;
 
     if ((dir = g_dir_open(dirname, 0, NULL)) != NULL) {
         while ((file = g_dir_read_name(dir)) != NULL) {
@@ -250,6 +246,21 @@ extcap_get_extcap_paths(void)
     return paths;
 }
 
+/**
+ * Obtains a list of extcap program paths. Use g_slist_free_full(paths, g_free)
+ * to destroy the list.
+ */
+static GSList *
+extcap_get_extcap_paths(void)
+{
+    GSList *paths = NULL;
+
+    paths = extcap_get_extcap_paths_from_dir(paths, get_persconffile_path("extcap", FALSE));
+    paths = extcap_get_extcap_paths_from_dir(paths, get_extcap_dir());
+
+    return paths;
+}
+
 static extcap_interface *
 extcap_find_interface_for_ifname(const gchar *ifname)
 {
@@ -1688,6 +1699,9 @@ extcap_ensure_interface(const gchar * toolname, gboolean create_if_nonexist)
         _loaded_interfaces = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, extcap_free_interface);
 
     element = (extcap_info *) g_hash_table_lookup(_loaded_interfaces, toolname );
+    if ( element )
+        return NULL;
+
     if ( ! element && create_if_nonexist )
     {
         g_hash_table_insert(_loaded_interfaces, g_strdup(toolname), g_new0(extcap_info, 1));
@@ -1753,7 +1767,8 @@ process_new_extcap(const char *extcap, char *output)
     element = extcap_ensure_interface(toolname, TRUE);
     if ( element == NULL )
     {
-        g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_ERROR, "Cannot store interface %s, maybe duplicate?", extcap );
+        g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_WARNING,
+            "Cannot store interface %s, already loaded as personal plugin", extcap );
         g_list_foreach(interfaces, remove_extcap_entry, NULL);
         g_list_free(interfaces);
         g_list_free(interface_keys);
diff --git a/ui/qt/about_dialog.cpp b/ui/qt/about_dialog.cpp
index 7cb00132e1..50c4482370 100644
--- a/ui/qt/about_dialog.cpp
+++ b/ui/qt/about_dialog.cpp
@@ -233,10 +233,8 @@ FolderListModel::FolderListModel(QObject * parent):
 #endif
 
     /* Extcap */
-    QStringList extPaths = QString(get_extcap_dir()).split(G_SEARCHPATH_SEPARATOR_S);
-
-    foreach(QString path, extPaths)
-        appendRow( QStringList() << tr("Extcap path") << path.trimmed() << tr("Extcap Plugins search path"));
+    appendRow( QStringList() << tr("Personal Extcap path") << QString(get_persconffile_path("extcap", FALSE)).trimmed() << tr("Extcap Plugins search path"));
+    appendRow( QStringList() << tr("Global Extcap path") << QString(get_extcap_dir()).trimmed() << tr("Extcap Plugins search path"));
 
 #ifdef HAVE_MAXMINDDB
     /* MaxMind DB */