commit 0342874: [Feature] Lua_trie: Allow to report start of the match

[Vsevolod Stakhov]

Author: Vsevolod Stakhov
Date: 2020-10-26 18:04:31 +0000
URL: https://github.com/rspamd/rspamd/commit/03428744014f6b5991ab7a838a5d8b2f49922d14 (HEAD -> master)

[Feature] Lua_trie: Allow to report start of the match

---
 src/lua/lua_trie.c | 69 ++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 51 insertions(+), 18 deletions(-)

diff --git a/src/lua/lua_trie.c b/src/lua/lua_trie.c
index 7c63fc687..33e5832a8 100644
--- a/src/lua/lua_trie.c
+++ b/src/lua/lua_trie.c
@@ -160,23 +160,39 @@ lua_trie_create (lua_State *L)
 	return 1;
 }
 
+#define PUSH_TRIE_MATCH(L, start, end, report_start) do { \
+	if (report_start) { \
+		lua_createtable (L, 2, 0); \
+		lua_pushinteger (L, (start)); \
+		lua_rawseti (L, -2, 1); \
+		lua_pushinteger (L, (end)); \
+		lua_rawseti (L, -2, 2); \
+	} \
+	else { \
+		lua_pushinteger (L, (end)); \
+	} \
+} while(0)
+
 /* Normal callback type */
 static gint
-lua_trie_callback (struct rspamd_multipattern *mp,
-		guint strnum,
-		gint match_start,
-		gint textpos,
-		const gchar *text,
-		gsize len,
-		void *context)
+lua_trie_lua_cb_callback (struct rspamd_multipattern *mp,
+						  guint strnum,
+						  gint match_start,
+						  gint textpos,
+						  const gchar *text,
+						  gsize len,
+						  void *context)
 {
 	lua_State *L = context;
 	gint ret;
 
+	gboolean report_start = lua_toboolean (L, -1);
+
 	/* Function */
 	lua_pushvalue (L, 3);
 	lua_pushinteger (L, strnum + 1);
-	lua_pushinteger (L, textpos);
+
+	PUSH_TRIE_MATCH (L, match_start, textpos, report_start);
 
 	if (lua_pcall (L, 2, 1, 0) != 0) {
 		msg_info ("call to trie callback has failed: %s",
@@ -204,13 +220,14 @@ lua_trie_table_callback (struct rspamd_multipattern *mp,
 {
 	lua_State *L = context;
 
+	gint report_start = lua_toboolean (L, -2);
 	/* Set table, indexed by pattern number */
 	lua_rawgeti (L, -1, strnum + 1);
 
 	if (lua_istable (L, -1)) {
 		/* Already have table, add offset */
 		gsize last = rspamd_lua_table_size (L, -1);
-		lua_pushinteger (L, textpos);
+		PUSH_TRIE_MATCH (L, match_start, textpos, report_start);
 		lua_rawseti (L, -2, last + 1);
 		/* Remove table from the stack */
 		lua_pop (L, 1);
@@ -220,7 +237,7 @@ lua_trie_table_callback (struct rspamd_multipattern *mp,
 		lua_pop (L, 1);
 		/* New table */
 		lua_newtable (L);
-		lua_pushinteger (L, textpos);
+		PUSH_TRIE_MATCH (L, match_start, textpos, report_start);
 		lua_rawseti (L, -2, 1);
 		lua_rawseti (L, -2, strnum + 1);
 	}
@@ -247,10 +264,11 @@ lua_trie_search_str (lua_State *L, struct rspamd_multipattern *trie,
 }
 
 /***
- * @method trie:match(input, [cb])
+ * @method trie:match(input, [cb][, report_start])
  * Search for patterns in `input` invoking `cb` optionally ignoring case
  * @param {table or string} input one or several (if `input` is an array) strings of input text
  * @param {function} cb callback called on each pattern match in form `function (idx, pos)` where `idx` is a numeric index of pattern (starting from 1) and `pos` is a numeric offset where the pattern ends
+ * @param {boolean} report_start report both start and end offset when matching patterns
  * @return {boolean} `true` if any pattern has been found (`cb` might be called multiple times however). If `cb` is not defined then it returns a table of match positions indexed by pattern number
  */
 static gint
@@ -260,16 +278,29 @@ lua_trie_match (lua_State *L)
 	struct rspamd_multipattern *trie = lua_check_trie (L, 1);
 	const gchar *text;
 	gsize len;
-	gboolean found = FALSE;
+	gboolean found = FALSE, report_start = FALSE;
 	struct rspamd_lua_text *t;
-	rspamd_multipattern_cb_t cb = lua_trie_callback;
+	rspamd_multipattern_cb_t cb = lua_trie_lua_cb_callback;
+
+	gint old_top = lua_gettop (L);
 
 	if (trie) {
 		if (lua_type (L, 3) != LUA_TFUNCTION) {
+			if (lua_isboolean (L, 3)) {
+				report_start = lua_toboolean (L, 3);
+			}
+
+			lua_pushboolean (L, report_start);
 			/* Table like match */
 			lua_newtable (L);
 			cb = lua_trie_table_callback;
 		}
+		else {
+			if (lua_isboolean (L, 4)) {
+				report_start = lua_toboolean (L, 4);
+			}
+			lua_pushboolean (L, report_start);
+		}
 
 		if (lua_type (L, 2) == LUA_TTABLE) {
 			lua_pushvalue (L, 2);
@@ -294,8 +325,6 @@ lua_trie_match (lua_State *L)
 				}
 				lua_pop (L, 1);
 			}
-
-			lua_pop (L, 1); /* table */
 		}
 		else if (lua_type (L, 2) == LUA_TSTRING) {
 			text = lua_tolstring (L, 2, &len);
@@ -314,8 +343,12 @@ lua_trie_match (lua_State *L)
 	}
 
 	if (lua_type (L, 3) == LUA_TFUNCTION) {
+		lua_settop (L, old_top);
 		lua_pushboolean (L, found);
 	}
+	else {
+		lua_remove (L, -2);
+	}
 
 	return 1;
 }
@@ -338,7 +371,7 @@ lua_trie_search_mime (lua_State *L)
 	const gchar *text;
 	gsize len, i;
 	gboolean found = FALSE;
-	rspamd_multipattern_cb_t cb = lua_trie_callback;
+	rspamd_multipattern_cb_t cb = lua_trie_lua_cb_callback;
 
 	if (trie && task) {
 		PTR_ARRAY_FOREACH (MESSAGE_FIELD (task, text_parts), i, part) {
@@ -379,7 +412,7 @@ lua_trie_search_rawmsg (lua_State *L)
 		text = task->msg.begin;
 		len = task->msg.len;
 
-		if (lua_trie_search_str (L, trie, text, len, lua_trie_callback) != 0) {
+		if (lua_trie_search_str (L, trie, text, len, lua_trie_lua_cb_callback) != 0) {
 			found = TRUE;
 		}
 	}
@@ -417,7 +450,7 @@ lua_trie_search_rawbody (lua_State *L)
 			len = task->msg.len;
 		}
 
-		if (lua_trie_search_str (L, trie, text, len, lua_trie_callback) != 0) {
+		if (lua_trie_search_str (L, trie, text, len, lua_trie_lua_cb_callback) != 0) {
 			found = TRUE;
 		}
 	}