lua: support bufferlist concatenation

Signed-off-by: Noah Watkins <noahwatkins@gmail.com>

3 files changed, 63 insertions, 0 deletions

diff --git a/src/liblua/src/lua_bufferlist.cc b/src/liblua/src/lua_bufferlist.cc
index a5e4e56dbd0..1ff29b8fad2 100644
--- a/src/liblua/src/lua_bufferlist.cc
+++ b/src/liblua/src/lua_bufferlist.cc
@@ -121,6 +121,19 @@ static int bl_le(lua_State *L)
 }
 
 /*
+ * Bufferlist concatentation
+ */
+static int bl_concat(lua_State *L)
+{
+  bufferlist *bl1 = clslua_checkbufferlist(L, 1);
+  bufferlist *bl2 = clslua_checkbufferlist(L, 2);
+  bufferlist *ret = clslua_pushbufferlist(L, NULL);
+  ret->append(bl1->c_str(), bl1->length());
+  ret->append(bl2->c_str(), bl2->length());
+  return 1;
+}
+
+/*
  * Garbage collect bufferlist
  */
 static int bl_gc(lua_State *L)
@@ -136,6 +149,7 @@ static int bl_gc(lua_State *L)
 static const struct luaL_Reg bufferlist_methods[] = {
   {"str", bl_str},
   {"append", bl_append},
+  {"__concat", bl_concat},
   {"__len", bl_len},
   {"__lt", bl_lt},
   {"__le", bl_le},
diff --git a/src/test/cls_lua/test_cls_lua.cc b/src/test/cls_lua/test_cls_lua.cc
index 004f56ccc61..f802cd85645 100644
--- a/src/test/cls_lua/test_cls_lua.cc
+++ b/src/test/cls_lua/test_cls_lua.cc
@@ -383,3 +383,9 @@ TEST_F(ClsLua, BufferlistCompare) {
   ASSERT_EQ(0, clslua_exec(test_script, NULL, "bl_lt"));
   ASSERT_EQ(0, clslua_exec(test_script, NULL, "bl_le"));
 }
+
+TEST_F(ClsLua, BufferlistConcat) {
+  ASSERT_EQ(0, clslua_exec(test_script, NULL, "bl_concat_eq"));
+  ASSERT_EQ(0, clslua_exec(test_script, NULL, "bl_concat_ne"));
+  ASSERT_EQ(0, clslua_exec(test_script, NULL, "bl_concat_immut"));
+}
diff --git a/src/test/cls_lua/test_script.lua b/src/test/cls_lua/test_script.lua
index b406481673e..e3663acc46a 100644
--- a/src/test/cls_lua/test_script.lua
+++ b/src/test/cls_lua/test_script.lua
@@ -230,6 +230,49 @@ cls.register(bl_lt)
 cls.register(bl_le)
 
 --
+-- Bufferlist concat
+--
+function bl_concat_eq()
+  local a = bufferlist.new()
+  local b = bufferlist.new()
+  local ab = bufferlist.new()
+  a:append('A')
+  b:append('B')
+  ab:append('AB')
+  assert(a .. b == ab)
+end
+
+function bl_concat_ne()
+  local a = bufferlist.new()
+  local b = bufferlist.new()
+  local ab = bufferlist.new()
+  a:append('A')
+  b:append('B')
+  ab:append('AB')
+  assert(b .. a ~= ab)
+end
+
+function bl_concat_immut()
+  local a = bufferlist.new()
+  local b = bufferlist.new()
+  local ab = bufferlist.new()
+  a:append('A')
+  b:append('B')
+  ab:append('AB')
+  x = a .. b
+  assert(x == ab)
+  b:append('C')
+  assert(x == ab)
+  local bc = bufferlist.new()
+  bc:append('BC')
+  assert(b == bc)
+end
+
+cls.register(bl_concat_eq)
+cls.register(bl_concat_ne)
+cls.register(bl_concat_immut)
+
+--
 -- RunError
 --
 function runerr_a()