[Feature] Lua_text: Implement flattening of the input tables

diff --git a/src/lua/lua_text.c b/src/lua/lua_text.c
index 3f024d236d66840277b2877fbfd61ac38aca4a88..f24416d29e015b1c9b47331c9ea9177cd3b30a21 100644 (file)
--- a/src/lua/lua_text.c
+++ b/src/lua/lua_text.c
@@ -196,31 +196,24 @@ lua_text_fromstring (lua_State *L)
        return 1;
 }
 
-static gint
-lua_text_fromtable (lua_State *L)
+#define MAX_REC 10
+
+static void
+lua_text_tbl_length (lua_State *L, gsize dlen, gsize *dest, guint rec)
 {
-       LUA_TRACE_POINT;
-       const gchar *delim = "", *st;
-       struct rspamd_lua_text *t, *elt;
-       gsize textlen = 0, dlen, stlen, tblen;
-       gchar *dest;
+       gsize tblen, stlen;
+       struct rspamd_lua_text *elt;
 
-       if (!lua_istable (L, 1)) {
-               return luaL_error (L, "invalid arguments");
-       }
+       if (rec > MAX_REC) {
+               luaL_error (L, "lua_text_tbl_length: recursion limit exceeded");
 
-       if (lua_type (L, 2) == LUA_TSTRING) {
-               delim = lua_tolstring (L, 2, &dlen);
-       }
-       else {
-               dlen = 0;
+               return;
        }
 
-       /* Calculate length needed */
-       tblen = rspamd_lua_table_size (L, 1);
+       tblen = rspamd_lua_table_size (L, -1);
 
-       for (guint i = 0; i < tblen; i ++) {
-               lua_rawgeti (L, 1, i + 1);
+       for (gsize i = 0; i < tblen; i ++) {
+               lua_rawgeti (L, -1, i + 1);
 
                if (lua_type (L, -1) == LUA_TSTRING) {
 #if LUA_VERSION_NUM >= 502
@@ -228,55 +221,114 @@ lua_text_fromtable (lua_State *L)
 #else
                        stlen = lua_objlen (L, -1);
 #endif
-                       textlen += stlen;
+                       (*dest) += stlen;
                }
-               else {
-                       elt = lua_check_text (L, -1);
+               else if (lua_type (L, -1) == LUA_TUSERDATA){
+                       elt = (struct rspamd_lua_text *)lua_touserdata (L, -1);
 
                        if (elt) {
-                               textlen += elt->len;
+                               (*dest) += elt->len;
                        }
                }
+               else if (lua_type (L, -1) == LUA_TTABLE) {
+                       lua_text_tbl_length (L, dlen, dest, rec + 1);
+               }
 
                if (i != tblen - 1) {
-                       textlen += dlen;
+                       (*dest) += dlen;
                }
 
                lua_pop (L, 1);
        }
+}
 
-       /* Allocate new text */
-       t = lua_newuserdata (L, sizeof (*t));
-       dest = g_malloc (textlen);
-       t->start = dest;
-       t->len = textlen;
-       t->flags = RSPAMD_TEXT_FLAG_OWN;
-       rspamd_lua_setclass (L, "rspamd{text}", -1);
+static void
+lua_text_tbl_append (lua_State *L,
+                                        const gchar *delim,
+                                        gsize dlen,
+                                        gchar **dest,
+                                        guint rec)
+{
+       const gchar *st;
+       gsize tblen, stlen;
+       struct rspamd_lua_text *elt;
+
+       if (rec > MAX_REC) {
+               luaL_error (L, "lua_text_tbl_length: recursion limit exceeded");
+
+               return;
+       }
+
+       tblen = rspamd_lua_table_size (L, -1);
 
        for (guint i = 0; i < tblen; i ++) {
-               lua_rawgeti (L, 1, i + 1);
+               lua_rawgeti (L, -1, i + 1);
 
                if (lua_type (L, -1) == LUA_TSTRING) {
                        st = lua_tolstring (L, -1, &stlen);
-                       memcpy (dest, st, stlen);
-                       dest += stlen;
+                       memcpy ((*dest), st, stlen);
+                       (*dest) += stlen;
                }
-               else {
-                       elt = lua_check_text (L, -1);
+               else if (lua_type (L, -1) == LUA_TUSERDATA){
+                       elt = (struct rspamd_lua_text *)lua_touserdata (L, -1);
 
                        if (elt) {
-                               memcpy (dest, elt->start, elt->len);
-                               dest += elt->len;
+                               memcpy ((*dest), elt->start, elt->len);
+                               (*dest) += elt->len;
                        }
                }
+               else if (lua_type (L, -1) == LUA_TTABLE) {
+                       lua_text_tbl_append (L, delim, dlen, dest, rec + 1);
+               }
 
                if (dlen && i != tblen - 1) {
-                       memcpy (dest, delim, dlen);
-                       dest += dlen;
+                       memcpy ((*dest), delim, dlen);
+                       (*dest) += dlen;
                }
 
                lua_pop (L, 1);
        }
+}
+
+static gint
+lua_text_fromtable (lua_State *L)
+{
+       LUA_TRACE_POINT;
+       const gchar *delim = "";
+       struct rspamd_lua_text *t;
+       gsize textlen = 0, dlen, oldtop = lua_gettop (L);
+       gchar *dest;
+
+       if (!lua_istable (L, 1)) {
+               return luaL_error (L, "invalid arguments");
+       }
+
+       if (lua_type (L, 2) == LUA_TSTRING) {
+               delim = lua_tolstring (L, 2, &dlen);
+       }
+       else {
+               dlen = 0;
+       }
+
+       /* Calculate length needed */
+       lua_pushvalue (L, 1);
+       lua_text_tbl_length (L, dlen, &textlen, 0);
+       lua_pop (L, 1);
+
+       /* Allocate new text */
+       t = lua_newuserdata (L, sizeof (*t));
+       dest = g_malloc (textlen);
+       t->start = dest;
+       t->len = textlen;
+       t->flags = RSPAMD_TEXT_FLAG_OWN;
+       rspamd_lua_setclass (L, "rspamd{text}", -1);
+
+       lua_pushvalue (L, 1);
+       lua_text_tbl_append (L, delim, dlen, &dest, 0);
+       lua_pop (L, 1); /* Table arg */
+
+       gint newtop = lua_gettop (L);
+       g_assert ( newtop== oldtop + 1);
 
        return 1;
 }