wsutil: Initialize and store plugin personal dir

Obviate allocation on every call to get_plugins_pers_dir().

Change-Id: I089ae499f93739d490d4552f59b5db5996f7d26f
Reviewed-on: https://code.wireshark.org/review/23495
Petri-Dish: João Valverde <j@v6e.pt>
Reviewed-by: Michael Mann <mmann78@netscape.net>
Reviewed-by: João Valverde <j@v6e.pt>

3 files changed, 24 insertions, 18 deletions

diff --git a/wsutil/filesystem.c b/wsutil/filesystem.c
index 939e4d3f05..2a2c4bab5f 100644
--- a/wsutil/filesystem.c
+++ b/wsutil/filesystem.c
@@ -959,6 +959,7 @@ get_datafile_dir(void)
  *    configure script.
  */
 static char *plugin_dir = NULL;
+static char *plugin_pers_dir = NULL;
 
 static void
 init_plugin_dir(void)
@@ -1034,6 +1035,12 @@ init_plugin_dir(void)
 }
 #endif /* HAVE_PLUGINS || HAVE_LUA */
 
+static void
+init_plugin_pers_dir(void)
+{
+    plugin_pers_dir = get_persconffile_path(PLUGINS_DIR_NAME, FALSE);
+}
+
 /*
  * Get the directory in which the plugins are stored.
  */
@@ -1048,6 +1055,15 @@ get_plugin_dir(void)
 #endif
 }
 
+/* Get the personal plugin dir */
+const char *
+get_plugins_pers_dir(void)
+{
+    if (!plugin_pers_dir)
+        init_plugin_pers_dir();
+    return plugin_pers_dir;
+}
+
 #if defined(HAVE_EXTCAP)
 /*
  * Find the directory where the extcap hooks are stored.
@@ -1883,14 +1899,6 @@ get_datafile_path(const char *filename)
     }
 }
 
-/* Get the personal plugin dir */
-/* Return value is malloced so the caller should g_free() it. */
-char *
-get_plugins_pers_dir(void)
-{
-    return get_persconffile_path(PLUGINS_DIR_NAME, FALSE);
-}
-
 /*
  * Return an error message for UNIX-style errno indications on open or
  * create operations.
@@ -2227,6 +2235,8 @@ free_progdirs(void)
 #if defined(HAVE_PLUGINS) || defined(HAVE_LUA)
     g_free(plugin_dir);
     plugin_dir = NULL;
+    g_free(plugin_pers_dir);
+    plugin_pers_dir = NULL;
 #endif
 #ifdef HAVE_EXTCAP
     g_free(extcap_dir);
diff --git a/wsutil/filesystem.h b/wsutil/filesystem.h
index f6c0e0899e..4ccc159ed7 100644
--- a/wsutil/filesystem.h
+++ b/wsutil/filesystem.h
@@ -56,6 +56,11 @@ WS_DLL_PUBLIC const char *get_progfile_dir(void);
 WS_DLL_PUBLIC const char *get_plugin_dir(void);
 
 /*
+ * Get the personal plugin dir.
+ */
+WS_DLL_PUBLIC const char *get_plugins_pers_dir(void);
+
+/*
  * Get the directory in which extcap hooks are stored; this must not be called
  * before init_progfile_dir() is called, as they might be stored in a
  * subdirectory of the program file directory.
@@ -84,12 +89,6 @@ WS_DLL_PUBLIC const char *get_datafile_dir(void);
 WS_DLL_PUBLIC char *get_datafile_path(const char *filename);
 
 /*
- * Get the personal plugin dir.
- * Return value is malloced so the caller should g_free() it.
- */
-WS_DLL_PUBLIC char *get_plugins_pers_dir(void);
-
-/*
  * Get the directory in which files that, at least on UNIX, are
  * system files (such as "/etc/ethers") are stored; on Windows,
  * there's no "/etc" directory, so we get them from the Wireshark
diff --git a/wsutil/plugins.c b/wsutil/plugins.c
index 76bb59d770..047a6cb721 100644
--- a/wsutil/plugins.c
+++ b/wsutil/plugins.c
@@ -285,7 +285,6 @@ scan_plugins(plugin_load_failure_mode mode)
     const char *plugin_dir;
     const char *name;
     char *plugin_dir_path;
-    char *plugins_pers_dir;
     WS_DIR *dir;                /* scanned directory */
     WS_DIRENT *file;            /* current file */
 
@@ -353,9 +352,7 @@ scan_plugins(plugin_load_failure_mode mode)
          */
         if (!started_with_special_privs())
         {
-            plugins_pers_dir = get_plugins_pers_dir();
-            plugins_scan_dir(plugins_pers_dir, mode);
-            g_free(plugins_pers_dir);
+            plugins_scan_dir(get_plugins_pers_dir(), mode);
         }
     }
 }