lua: support cls_cxx_write and bufferlist::length

Signed-off-by: Adam Manzanares <nmtadam@gmail.com>
Reviewed-by: Noah Watkins <noahwatkins@gmail.com>

4 files changed, 52 insertions, 0 deletions

diff --git a/src/cls/lua/cls_lua.cc b/src/cls/lua/cls_lua.cc
index bf4dc6a6e16..d846df3c226 100644
--- a/src/cls/lua/cls_lua.cc
+++ b/src/cls/lua/cls_lua.cc
@@ -301,6 +301,18 @@ static int clslua_read(lua_State *L)
 }
 
 /*
+ * cls_cxx_write
+ */
+static int clslua_write(lua_State *L){
+  cls_method_context_t hctx = clslua_get_hctx(L);
+  int offset = luaL_checkint(L, 1);
+  int length = luaL_checkint(L, 2);
+  bufferlist *bl = clslua_checkbufferlist(L, 3);
+  int ret = cls_cxx_write(hctx, offset, length, bl);
+  return clslua_opresult(L, (ret == 0), ret, 0);
+}
+
+/*
  * cls_cxx_map_get_val
  */
 static int clslua_map_get_val(lua_State *L)
@@ -334,6 +346,7 @@ static const luaL_Reg clslua_lib[] = {
   {"remove", clslua_remove},
   {"stat", clslua_stat},
   {"read", clslua_read},
+  {"write", clslua_write},
   {"map_get_val", clslua_map_get_val},
   {"map_set_val", clslua_map_set_val},
   {NULL, NULL}
diff --git a/src/liblua/src/lua_bufferlist.cc b/src/liblua/src/lua_bufferlist.cc
index bb2b6084633..09abb755d25 100644
--- a/src/liblua/src/lua_bufferlist.cc
+++ b/src/liblua/src/lua_bufferlist.cc
@@ -78,6 +78,16 @@ static int bl_append(lua_State *L)
 }
 
 /*
+ * Return the length in bytes of bufferlist
+ */
+static int bl_length(lua_State *L)
+{
+  bufferlist *bl = clslua_checkbufferlist(L);
+  lua_pushinteger(L, bl->length());
+  return 1;
+}
+
+/*
  * Perform byte-for-byte bufferlist equality test
  */
 static int bl_eq(lua_State *L)
@@ -104,6 +114,7 @@ static int bl_gc(lua_State *L)
 static const struct luaL_Reg bufferlist_methods[] = {
   {"str", bl_str},
   {"append", bl_append},
+  {"length", bl_length},
   {"__gc", bl_gc},
   {"__eq", bl_eq},
   {NULL, NULL}
diff --git a/src/test/cls_lua/test_cls_lua.cc b/src/test/cls_lua/test_cls_lua.cc
index e73577f6a8a..666ffa3c2b4 100644
--- a/src/test/cls_lua/test_cls_lua.cc
+++ b/src/test/cls_lua/test_cls_lua.cc
@@ -123,6 +123,25 @@ librados::IoCtx ClsLua::ioctx;
 string ClsLua::pool_name;
 string ClsLua::test_script;
 
+TEST_F(ClsLua, Write) {
+  /* write some data into object */
+  string written = "Hello World";
+  bufferlist inbl;
+  ::encode(written, inbl);
+  ASSERT_EQ(0, clslua_exec(test_script, &inbl, "write"));
+
+  /* have Lua read out of the object */
+  uint64_t size;
+  bufferlist outbl;
+  ASSERT_EQ(0, ioctx.stat(oid, &size, NULL));
+  ASSERT_EQ(size, (uint64_t)ioctx.read(oid, outbl, size, 0) );
+
+  /* compare what Lua read to what we wrote */
+  string read;
+  ::decode(read, outbl);
+  ASSERT_EQ(read, written);
+}
+
 TEST_F(ClsLua, SyntaxError) {
   ASSERT_EQ(-EIO, clslua_exec("-"));
 }
diff --git a/src/test/cls_lua/test_script.lua b/src/test/cls_lua/test_script.lua
index 73c602a9087..39f25974c3c 100644
--- a/src/test/cls_lua/test_script.lua
+++ b/src/test/cls_lua/test_script.lua
@@ -16,6 +16,15 @@ end
 cls.register(read)
 
 --
+-- Write
+--
+function write(input, output)
+  cls.write(0, input:length(), input)
+end
+
+cls.register(write)
+
+--
 -- MsgPack
 --
 function msgpack(input, output)