Qt: Reload Lua expert infos

Support reloading Lua plugins with expert infos.
Use the same delayed deregister logic as for fields.

Change-Id: I36efa0820050b3a7afed4de7a8b0fa16805e8dfa
Reviewed-on: https://code.wireshark.org/review/12498
Petri-Dish: Stig Bjørlykke <stig@bjorlykke.org>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>
(cherry picked from commit ea1789f925f49027e6b2864e6cc846b7016dc13b)
Reviewed-on: https://code.wireshark.org/review/12526
Reviewed-by: Stig Bjørlykke <stig@bjorlykke.org>

5 files changed, 55 insertions, 5 deletions

diff --git a/epan/expert.c b/epan/expert.c
index 4a3d692f06..6802997d32 100644
--- a/epan/expert.c
+++ b/epan/expert.c
@@ -68,6 +68,9 @@ static gpa_expertinfo_t gpa_expertinfo;
 /* Hash table of abbreviations and IDs */
 static GHashTable *gpa_name_map = NULL;
 
+/* Deregistered expert infos */
+static GPtrArray *deregistered_expertinfos = NULL;
+
 const value_string expert_group_vals[] = {
 	{ PI_CHECKSUM,          "Checksum" },
 	{ PI_SEQUENCE,          "Sequence" },
@@ -187,6 +190,7 @@ static void uat_expert_post_update_cb(void)
 	if((guint)eiindex >= gpa_expertinfo.len && getenv("WIRESHARK_ABORT_ON_DISSECTOR_BUG"))   \
 		g_error("Unregistered expert info! index=%d", eiindex);                          \
 	DISSECTOR_ASSERT_HINT((guint)eiindex < gpa_expertinfo.len, "Unregistered expert info!"); \
+	DISSECTOR_ASSERT_HINT(gpa_expertinfo.ei[eiindex] != NULL, "Unregistered expert info!");	\
 	expinfo = gpa_expertinfo.ei[eiindex];
 
 void
@@ -265,6 +269,7 @@ expert_init(void)
 	gpa_expertinfo.ei            = NULL;
 	gpa_name_map                 = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, NULL);
 	uat_saved_fields             = g_array_new(FALSE, FALSE, sizeof(expert_field_info*));
+	deregistered_expertinfos     = g_ptr_array_new();
 }
 
 void
@@ -293,6 +298,11 @@ expert_cleanup(void)
 		g_array_free(uat_saved_fields, TRUE);
 		uat_saved_fields = NULL;
 	}
+
+	if (deregistered_expertinfos) {
+		g_ptr_array_free(deregistered_expertinfos, FALSE);
+		deregistered_expertinfos = NULL;
+	}
 }
 
 
@@ -323,9 +333,35 @@ expert_module_t *expert_register_protocol(int id)
 	return module;
 }
 
-void expert_deregister_protocol (expert_module_t *module)
+void
+expert_deregister_expertinfo (const char *abbrev)
+{
+	expert_field_info *expinfo = (expert_field_info*)g_hash_table_lookup(gpa_name_map, abbrev);
+	if (expinfo) {
+		g_ptr_array_add(deregistered_expertinfos, gpa_expertinfo.ei[expinfo->id]);
+		g_hash_table_steal(gpa_name_map, abbrev);
+	}
+}
+
+void
+expert_deregister_protocol (expert_module_t *module)
+{
+	wmem_free(wmem_epan_scope(), module);
+}
+
+static void
+free_deregistered_expertinfo (gpointer data, gpointer user_data _U_)
+{
+	expert_field_info *expinfo = (expert_field_info *) data;
+	gpa_expertinfo.ei[expinfo->id] = NULL; /* Invalidate this id */
+}
+
+void
+expert_free_deregistered_expertinfos (void)
 {
-    wmem_free(wmem_epan_scope(), module);
+	g_ptr_array_foreach(deregistered_expertinfos, free_deregistered_expertinfo, NULL);
+	g_ptr_array_free(deregistered_expertinfos, TRUE);
+	deregistered_expertinfos = g_ptr_array_new();
 }
 
 static int
diff --git a/epan/expert.h b/epan/expert.h
index fabe2f67d3..bf5fcdb1ee 100644
--- a/epan/expert.h
+++ b/epan/expert.h
@@ -172,11 +172,21 @@ proto_tree_add_expert_format(proto_tree *tree, packet_info *pinfo, expert_field
 WS_DLL_PUBLIC expert_module_t *expert_register_protocol(int id);
 
 /**
+ * Deregister a expert info.
+ */
+void expert_deregister_expertinfo (const char *abbrev);
+
+/**
  * Deregister expert info from a protocol.
  */
 WS_DLL_PUBLIC void expert_deregister_protocol (expert_module_t *module);
 
 /**
+ * Free deregistered expert infos.
+ */
+void expert_free_deregistered_expertinfos (void);
+
+/**
  * Get summary text of an expert_info field.
  * This is intended for use in expert_add_info_format or proto_tree_add_expert_format
  * to get the "base" string to then append additional information
diff --git a/epan/proto.c b/epan/proto.c
index a87e14fe90..e75a8e6252 100644
--- a/epan/proto.c
+++ b/epan/proto.c
@@ -5349,6 +5349,7 @@ proto_deregister_protocol(const char *short_name)
     for (i = 0; i < protocol->fields->len; i++) {
         hfinfo = (header_field_info *)g_ptr_array_index(protocol->fields, i);
         hfinfo_remove_from_gpa_name_map(hfinfo);
+        expert_deregister_expertinfo(hfinfo->abbrev);
         g_ptr_array_add(deregistered_fields, gpa_hfinfo.hfi[hfinfo->id]);
     }
     g_ptr_array_free(protocol->fields, TRUE);
@@ -5865,6 +5866,8 @@ free_deregistered_data (gpointer data, gpointer user_data _U_)
 void
 proto_free_deregistered_fields (void)
 {
+    expert_free_deregistered_expertinfos();
+
     g_ptr_array_foreach(deregistered_fields, free_deregistered_field, NULL);
     g_ptr_array_free(deregistered_fields, TRUE);
     deregistered_fields = g_ptr_array_new();
diff --git a/epan/wslua/wslua_proto.c b/epan/wslua/wslua_proto.c
index 8721b451c7..8039f70372 100644
--- a/epan/wslua/wslua_proto.c
+++ b/epan/wslua/wslua_proto.c
@@ -715,6 +715,9 @@ int Proto_commit(lua_State* L) {
             eiri.eiinfo.severity = e->severity;
             eiri.eiinfo.summary  = e->text;
 
+            /* Copy this because it will be free'd when deregistering fields */
+            eiri.eiinfo.hf_info.hfinfo.name = g_strdup(eiri.eiinfo.hf_info.hfinfo.name);
+
             if (e->ids.ei != EI_INIT_EI || e->ids.hf != EI_INIT_HF) {
                 return luaL_error(L,"expert fields can be registered only once");
             }
diff --git a/epan/wslua/wslua_proto_expert.c b/epan/wslua/wslua_proto_expert.c
index 8a8079152c..e2d0452bce 100644
--- a/epan/wslua/wslua_proto_expert.c
+++ b/epan/wslua/wslua_proto_expert.c
@@ -70,7 +70,7 @@ WSLUA_CONSTRUCTOR ProtoExpert_new(lua_State* L) {
 
     pe->ids.ei   = EI_INIT_EI;
     pe->ids.hf   = EI_INIT_HF;
-    pe->abbrev     = g_strdup(abbr);
+    pe->abbrev   = g_strdup(abbr);
     pe->text     = g_strdup(text);
     pe->group    = group;
     pe->severity = severity;
@@ -101,8 +101,6 @@ static int ProtoExpert__gc(lua_State* L) {
 
     if (pe->ids.hf == -2) {
         /* Only free unregistered and deregistered ProtoExpert */
-        g_free((gchar *)pe->abbrev);
-        g_free((gchar *)pe->text);
         g_free(pe);
     }