Fix duplicate Display Filter Macro check

Since commit 4a1bd75b60171d781dc9f2d3ffd6d498acc74b1a
(https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=7471), the data
pointer does not match anything from the macros array.

This patch fixes a false warning by checking for duplicates before the
name is committed.

Bug: 10957
Change-Id: Id61110bf63de1de80b85524705a2df6a5e7be33a
Reviewed-on: https://code.wireshark.org/review/7119
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Reviewed-by: Michael Mann <mmann78@netscape.net>

1 files changed, 20 insertions, 15 deletions

diff --git a/epan/dfilter/dfilter-macro.c b/epan/dfilter/dfilter-macro.c
index 7f805859ad..234e2cea00 100644
--- a/epan/dfilter/dfilter-macro.c
+++ b/epan/dfilter/dfilter-macro.c
@@ -403,7 +403,7 @@ const gchar* dfilter_macro_apply(const gchar* text, gchar** error) {
 	return dfilter_macro_apply_recurse(text, 0, error);
 }
 
-static void macro_update(void* mp, gchar** error) {
+static void macro_update(void* mp, gchar** error _U_) {
 	dfilter_macro_t* m = (dfilter_macro_t*)mp;
 	GPtrArray* parts;
 	GArray* args_pos;
@@ -411,22 +411,9 @@ static void macro_update(void* mp, gchar** error) {
 	gchar* w;
 	gchar* part;
 	int argc = 0;
-	guint i;
 
 	DUMP_MACRO(m);
 
-	*error = NULL;
-
-	for (i = 0; i < num_macros; i++) {
-		if (m == &(macros[i])) continue;
-
-		if ( g_str_equal(m->name,macros[i].name) ) {
-			*error = g_strdup_printf("macro '%s' exists already", m->name);
-			m->usable = FALSE;
-			return;
-		}
-	}
-
 	/* Invalidate the display filter in case it's in use */
 	if (dfilter_macro_uat && dfilter_macro_uat->post_update_cb)
 	  dfilter_macro_uat->post_update_cb();
@@ -591,7 +578,9 @@ static void* macro_copy(void* dest, const void* orig, size_t len _U_) {
 	return d;
 }
 
-static gboolean macro_name_chk(void* r _U_, const char* in_name, guint name_len, const void* u1 _U_, const void* u2 _U_, char** error) {
+static gboolean macro_name_chk(void *mp, const char *in_name, guint name_len,
+		const void *u1 _U_, const void *u2 _U_, char **error) {
+	dfilter_macro_t* m = (dfilter_macro_t*)mp;
 	guint i;
 
 	if (name_len == 0) {
@@ -606,6 +595,22 @@ static gboolean macro_name_chk(void* r _U_, const char* in_name, guint name_len,
 		}
 	}
 
+	/* When loading (!m->name) or when adding/changing the an item with a
+	 * different name, check for uniqueness. NOTE: if a duplicate already
+	 * exists (because the user manually edited the file), then this will
+	 * not trigger a warning. */
+	if (!m->name || !g_str_equal(m->name, in_name)) {
+		for (i = 0; i < num_macros; i++) {
+			/* This a string field which is always NUL-terminated,
+			 * so no need to check name_len. */
+			if (g_str_equal(in_name, macros[i].name)) {
+				*error = g_strdup_printf("macro '%s' already exists",
+							 in_name);
+				return FALSE;
+			}
+		}
+	}
+
 	return TRUE;
 }