* DissectorTable.add does not allow to add lua protocols that don't have a dissector.

* ProtoFiled.uint checks the base to be a valid value to avoid an assertion in proto.c while registering the field array
* save one lua table lookup by using a reference to the dissectors table instead of looking for it by name
* set data_hanlde's value to avoid a crash while invoking it.
* make the TvbRange of Tree:add_item really optional. 


svn path=/trunk/; revision=17220

5 files changed, 66 insertions, 43 deletions

diff --git a/plugins/lua/lua_proto.c b/plugins/lua/lua_proto.c
index dd288cb192..31da270b10 100644
--- a/plugins/lua/lua_proto.c
+++ b/plugins/lua/lua_proto.c
@@ -427,21 +427,28 @@ static int ProtoField_integer(lua_State* L, enum ftenum type) {
     ProtoField f = g_malloc(sizeof(eth_field_t));
     const gchar* abbr = luaL_checkstring(L,1); 
     const gchar* name = luaL_optstring(L,2,abbr);
-    const gchar* base = luaL_optstring(L, 3, "BASE_DEC");
+    const gchar* base_str = luaL_optstring(L, 3, "BASE_DEC");
     value_string* vs = (lua_gettop(L) > 3) ? value_string_from_table(L,4) : NULL;
     int mask = luaL_optint(L, 5, 0x0);
     const gchar* blob = luaL_optstring(L,6,"");
+    base_display_e base = string_to_base(base_str);
 
+    if (base < BASE_DEC || base > BASE_HEX_DEC) {
+        luaL_argerror(L,3,"Base must be either BASE_DEC, BASE_HEX, BASE_OCT,"
+                      " BASE_DEC_HEX, BASE_DEC_HEX or BASE_HEX_DEC");
+        return 0;
+    }
 
     f->hfid = -2;
     f->name = g_strdup(name);
     f->abbr = g_strdup(abbr);
     f->type = type;
     f->vs = vs;
-    f->base = string_to_base(base);
+    f->base = base;
     f->mask = mask;
     f->blob = g_strdup(blob);
     
+    
     pushProtoField(L,f);
     
     return 1;
@@ -844,9 +851,7 @@ static int Proto_set_dissector(lua_State* L) {
     if (lua_isfunction(L,3)) {
         /* insert the dissector into the dissectors table */
        
-        lua_pushstring(L, LUA_DISSECTORS_TABLE);
-        lua_gettable(L, LUA_REGISTRYINDEX);
-
+        lua_rawgeti(L, LUA_REGISTRYINDEX, lua_dissectors_table_ref);
         lua_replace(L, 1);
         lua_pushstring(L,proto->name);
         lua_replace(L, 2);
@@ -1129,6 +1134,12 @@ static int DissectorTable_add (lua_State *L) {
         Proto p;
         p = toProto(L,3);
         handle = p->handle;
+        
+        if (! handle) {
+            luaL_error(L,"Protocol %s cannot be added to a table as it does not have a dissector",p->name);
+            return 0;
+        }
+        
     } else if ( isDissector(L,3) ) {
         handle = toDissector(L,3);
     } else {
@@ -1144,6 +1155,8 @@ static int DissectorTable_add (lua_State *L) {
     } else if ( type == FT_UINT32 || type == FT_UINT16 || type ==  FT_UINT8 || type ==  FT_UINT24 ) {
         int port = luaL_checkint(L, 2);
         dissector_add(dt->name, port, handle);
+    } else {
+        luaL_error(L,"Strange type %d for a DissectorTable",type);
     }
     
     return 0;
diff --git a/plugins/lua/lua_tree.c b/plugins/lua/lua_tree.c
index 2b9c79dbe8..3841dc5edd 100644
--- a/plugins/lua/lua_tree.c
+++ b/plugins/lua/lua_tree.c
@@ -141,7 +141,14 @@ static int ProtoTree_add_item_any(lua_State *L, gboolean little_endian) {
 
     tvbr = shiftTvbRange(L,1);
 
-    if (hfid > 0 && tvbr ) {
+    if (!tvbr) {
+        tvbr = ep_alloc(sizeof(struct _eth_tvbrange));
+        tvbr->tvb = lua_tvb;
+        tvbr->offset = 0;
+        tvbr->len = 0;
+    }
+    
+    if (hfid > 0 ) {
         if (lua_gettop(L)) {
             switch(type) {
                 case FT_PROTOCOL:
diff --git a/plugins/lua/lua_tvb.c b/plugins/lua/lua_tvb.c
index 5b86af79e2..91d46317fd 100644
--- a/plugins/lua/lua_tvb.c
+++ b/plugins/lua/lua_tvb.c
@@ -26,6 +26,22 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  */
 
+/*
+ *  XXX: TODO
+ *
+ *  having Tvbs and TvbRanges have a lifetime of just the dissector callback
+ *  but being user able to save them in global variables for later use
+ *  every lua value created with these should be NULLified after the dissector's
+ *  callback, pushXxx() gives back a pointer to the pointer it saves that has to be pushed
+ *  to a queue and NULLified before returning from packet_lua.
+ *
+ *  in order to do that we need to verify that every function in this file yields an
+ *  error if the Xxx ptr it uses is NULL.  
+ *
+ * the same would applies to Pinfo, Item and Tree
+ * Item and Tree are protected in the sense that the callbacks to these  
+ */
+
 #include "packet-lua.h"
 
 LUA_CLASS_DEFINE(Tvb,TVB,if (! *p) luaL_error(L,"null tvb"))
@@ -35,7 +51,6 @@ LUA_CLASS_DEFINE(ByteArray,BYTE_ARRAY,if (! *p) luaL_argerror(L,index,"null byte
 static int ByteArray_new(lua_State* L) {
     GByteArray* ba = g_byte_array_new();
     const gchar* s;
-    /* XXX: slow! */
     int nibble[2];
     int i = 0;
     gchar c;
@@ -48,6 +63,7 @@ static int ByteArray_new(lua_State* L) {
             return 0;
         }
         
+        /* XXX: slow! */
         for (; (c = *s); s++) {
             switch(c) {
                 case '0': case '1': case '2': case '3': case '4': case '5' : case '6' : case '7': case '8' : case '9' :
@@ -120,8 +136,6 @@ static int ByteArray_set_index(lua_State* L) {
     int idx = luaL_checkint(L,2);
     int v = luaL_checkint(L,3);
     
-    g_warning(">%p %d",ba,idx);
-
     if (!ba) return 0;
 
     if (idx == 0 && ! g_str_equal(luaL_optstring(L,2,""),"0") ) {
@@ -149,8 +163,6 @@ static int ByteArray_get_index(lua_State* L) {
     ByteArray ba = checkByteArray(L,1);
     int idx = luaL_checkint(L,2);
     
-    g_warning(">%p %d",ba,idx);
-
     if (!ba) return 0;
     
     if (idx == 0 && ! g_str_equal(luaL_optstring(L,2,""),"0") ) {
@@ -162,7 +174,6 @@ static int ByteArray_get_index(lua_State* L) {
         luaL_argerror(L,2,"index out of range");
         return 0;
     }
-    g_warning(">%d",idx);
     lua_pushnumber(L,ba->data[idx]);
     
     return 1;
diff --git a/plugins/lua/packet-lua.c b/plugins/lua/packet-lua.c
index 863c0a70d5..7ff4bee583 100644
--- a/plugins/lua/packet-lua.c
+++ b/plugins/lua/packet-lua.c
@@ -39,6 +39,8 @@ packet_info* lua_pinfo;
 proto_tree* lua_tree;
 tvbuff_t* lua_tvb;
 int lua_malformed;
+int lua_dissectors_table_ref;
+
 dissector_handle_t lua_data_handle;
 
 
@@ -99,28 +101,13 @@ void dissect_lua(tvbuff_t* tvb, packet_info* pinfo, proto_tree* tree) {
     /*
      * almost equivalent to Lua:
      * dissectors[current_proto](tvb,pinfo,tree)
-     * but it wont give an error if dissectors[current_proto] doesn't exist
      */
     
     lua_settop(L,0);
 
-    lua_pushstring(L, LUA_DISSECTORS_TABLE);
-    lua_gettable(L, LUA_REGISTRYINDEX);
-    
-    if (!lua_istable(L, -1)) {
-        proto_item* pi = proto_tree_add_text(tree,tvb,0,0,"Lua: either `" LUA_DISSECTORS_TABLE "' does not exist or it is not a table!");
-        expert_add_info_format(pinfo, pi, PI_DEBUG, PI_ERROR,"Lua Error");
-
-        lua_pinfo = NULL;
-        lua_tree = NULL;
-        lua_tvb = NULL;
-        
-        return;
-    }
-    
+    lua_rawgeti(L, LUA_REGISTRYINDEX, lua_dissectors_table_ref);    
     
     lua_pushstring(L, pinfo->current_proto);
-
     lua_gettable(L, -2);  
 
     lua_remove(L,1);
@@ -134,11 +121,15 @@ void dissect_lua(tvbuff_t* tvb, packet_info* pinfo, proto_tree* tree) {
         
         if  ( lua_pcall(L,3,0,0) ) {
             const gchar* error = lua_tostring(L,-1);
+
             proto_item* pi = proto_tree_add_text(tree,tvb,0,0,"Lua Error: %s",error);
             expert_add_info_format(pinfo, pi, PI_DEBUG, PI_ERROR ,"Lua Error");
         }
     } else {
-        /* XXX */   
+        proto_item* pi = proto_tree_add_text(tree,tvb,0,0,"Lua Error: did not find the %s dissector"
+                                             " in the dissectors table",pinfo->current_proto);
+        
+        expert_add_info_format(pinfo, pi, PI_DEBUG, PI_ERROR ,"Lua Error");
     }
     
     lua_pinfo = NULL;
@@ -229,6 +220,8 @@ void lua_load_script(const gchar* filename) {
         report_open_failure(filename,errno,FALSE);
         return;
     }
+
+    lua_settop(L,0);
     
     lua_pushcfunction(L,lua_main_error_handler);
     
@@ -236,25 +229,18 @@ void lua_load_script(const gchar* filename) {
         case 0:
             lua_pcall(L,0,0,1);
             fclose(file);
-            
-            lua_data_handle = NULL;
-            lua_pinfo = NULL;
-            lua_tree = NULL;
-            lua_tvb = NULL;
-            
-            lua_malformed = proto_get_id_by_filter_name("malformed");
-            
             return;
         case LUA_ERRSYNTAX: {
             report_failure("Lua: syntax error during precompilation of `%s':\n%s",filename,lua_tostring(L,-1));
+            fclose(file);
             return;
         }
         case LUA_ERRMEM:
             report_failure("Lua: memory allocation error during execution of %s",filename);
+            fclose(file);
             return;
     }
     
-    lua_settop(L,0);
 }
 
 void register_lua(void) {
@@ -342,9 +328,8 @@ void register_lua(void) {
     lua_newtable (L);
     lua_settable(L, LUA_GLOBALSINDEX);
     
-    lua_pushstring(L, LUA_DISSECTORS_TABLE);
     lua_newtable (L);
-    lua_settable(L, LUA_REGISTRYINDEX);
+    lua_dissectors_table_ref = luaL_ref(L, LUA_REGISTRYINDEX);
     
     for (i=0 ; i < filenames->len ; i++) {
         filename = g_ptr_array_index(filenames,i);
@@ -358,6 +343,13 @@ void register_lua(void) {
     lua_pushcfunction(L, lua_not_register_menu);
     lua_settable(L, LUA_GLOBALSINDEX);
     
+    lua_pinfo = NULL;
+    lua_tree = NULL;
+    lua_tvb = NULL;
+    
+    lua_data_handle = find_dissector("data");
+    lua_malformed = proto_get_id_by_filter_name("malformed");
+    
     return;
 }
 
diff --git a/plugins/lua/packet-lua.h b/plugins/lua/packet-lua.h
index d6e8b626f6..954ab41587 100644
--- a/plugins/lua/packet-lua.h
+++ b/plugins/lua/packet-lua.h
@@ -209,7 +209,7 @@ extern tvbuff_t* lua_tvb;
 extern int lua_malformed;
 extern dissector_handle_t lua_data_handle;
 extern gboolean lua_initialized;
-
+extern int lua_dissectors_table_ref;
 
 #define LUA_CLASS_DECLARE(C,CN) \
 extern C to##C(lua_State* L, int index); \
@@ -250,9 +250,9 @@ extern const gchar* lua_shiftstring(lua_State* L,int idx);
 extern int lua_register_menu(lua_State* L);
 extern int lua_new_dialog(lua_State* L);
 extern int lua_gui_enabled(lua_State* L);
-
+extern void proto_register_lua(void);
 extern GString* lua_register_all_taps(void);
 extern void lua_prime_all_fields(proto_tree* tree);
-void lua_register_subtrees(void);
+extern void lua_register_subtrees(void);
 
 #endif