// Executes an aggregation over the iterator.
func (e *ExecutionEngine) Aggregate() (interface{}, error) {
functionName := C.CString("sky_aggregate")
defer C.free(unsafe.Pointer(functionName))
C.lua_getfield(e.state, -10002, functionName)
C.lua_pushlightuserdata(e.state, unsafe.Pointer(e.cursor))
rc := C.lua_pcall(e.state, 1, 1, 0)
if rc != 0 {
luaErrString := C.GoString(C.lua_tolstring(e.state, -1, nil))
fmt.Println(e.FullAnnotatedSource())
return nil, fmt.Errorf("skyd.ExecutionEngine: Unable to aggregate: %s", luaErrString)
}
return e.decodeResult()
}
// Pcall calls a lua function. no panic
func (l *Lua) Pcall(fullname string, args ...interface{}) (returns []interface{}, err error) {
C.push_errfunc(l.State)
curTop := C.lua_gettop(l.State)
// get function
path := strings.Split(fullname, ".")
for i, name := range path {
if i == 0 {
C.lua_getfield(l.State, C.LUA_GLOBALSINDEX, cstr(name))
} else {
if C.lua_type(l.State, -1) != C.LUA_TTABLE {
return nil, fmt.Errorf("%s is not a function", fullname)
}
C.lua_pushstring(l.State, cstr(name))
C.lua_gettable(l.State, -2)
C.lua_remove(l.State, -2) // remove table
}
}
if C.lua_type(l.State, -1) != C.LUA_TFUNCTION {
return nil, fmt.Errorf("%s is not a function", fullname)
}
// args
for _, arg := range args {
l.pushGoValue(arg, "")
}
// call
l.err = nil
if ret := C.lua_pcall(l.State, C.int(len(args)), C.LUA_MULTRET, C.int(-(len(args))-2)); ret != 0 {
// error occured
return nil, fmt.Errorf("CALL ERROR: %s", C.GoString(C.lua_tolstring(l.State, -1, nil)))
} else if l.err != nil { // error raise by invokeGoFunc
return nil, l.err
} else {
// return values
nReturn := C.lua_gettop(l.State) - curTop
returns = make([]interface{}, int(nReturn))
for i := C.int(0); i < nReturn; i++ {
value, err := l.toGoValue(-1-i, interfaceType)
if err != nil {
return nil, err
}
returns[int(nReturn-1-i)] = value.Interface()
}
}
return
}
// Executes an merge over the iterator.
func (e *ExecutionEngine) Merge(results interface{}, data interface{}) (interface{}, error) {
functionName := C.CString("sky_merge")
defer C.free(unsafe.Pointer(functionName))
C.lua_getfield(e.state, -10002, functionName)
err := e.encodeArgument(results)
if err != nil {
return results, err
}
err = e.encodeArgument(data)
if err != nil {
return results, err
}
rc := C.lua_pcall(e.state, 2, 1, 0)
if rc != 0 {
luaErrString := C.GoString(C.lua_tolstring(e.state, -1, nil))
fmt.Println(e.FullAnnotatedSource())
return results, fmt.Errorf("skyd.ExecutionEngine: Unable to merge: %s", luaErrString)
}
return e.decodeResult()
}
// Initializes the cursor used by the script.
func (e *ExecutionEngine) initCursor() error {
// Create the cursor.
minPropertyId, maxPropertyId := e.propertyFile.NextIdentifiers()
e.cursor = C.sky_cursor_new((C.int32_t)(minPropertyId), (C.int32_t)(maxPropertyId))
e.cursor.context = unsafe.Pointer(e)
C.executionEngine_setNextObjectFunc(unsafe.Pointer(e.cursor))
// Initialize the cursor from within Lua.
functionName := C.CString("sky_init_cursor")
defer C.free(unsafe.Pointer(functionName))
C.lua_getfield(e.state, -10002, functionName)
C.lua_pushlightuserdata(e.state, unsafe.Pointer(e.cursor))
//fmt.Printf("%s\n\n", e.FullAnnotatedSource())
rc := C.lua_pcall(e.state, 1, 0, 0)
if rc != 0 {
luaErrString := C.GoString(C.lua_tolstring(e.state, -1, nil))
return fmt.Errorf("Unable to init cursor: %s", luaErrString)
}
return nil
}
// luaL_getmetatable
func (L *State) LGetMetaTable(tname string) {
Ctname := C.CString(tname)
defer C.free(unsafe.Pointer(Ctname))
C.lua_getfield(L.s, LUA_REGISTRYINDEX, Ctname)
}
// lua_getfield
func (L *State) GetField(index int, k string) {
Ck := C.CString(k)
defer C.free(unsafe.Pointer(Ck))
C.lua_getfield(L.s, C.int(index), Ck)
}
// Pushes onto the stack the value t[k], where t is the value at the
// given valid index.
func (this *State) Getfield(index int, k string) {
cs := C.CString(k)
defer C.free(unsafe.Pointer(cs))
C.lua_getfield(this.luastate, C.int(index), cs)
}
func (L *State) GetField(index int, k string) {
C.lua_getfield(L.s, C.int(index), C.CString(k))
}
func (l *Lua) getStackTraceback() string {
C.lua_getfield(l.State, C.LUA_GLOBALSINDEX, cstr("debug"))
C.lua_getfield(l.State, -1, cstr("traceback"))
C.lua_call(l.State, 0, 1)
return C.GoString(C.lua_tolstring(l.State, -1, nil))
}
//TODO: rename better... clashes with lua_getmetatable
func LGetMetaTable(L *State, tname string) {
//C.luaL_getmetatable(L.s,C.CString(tname));
C.lua_getfield(L.s, LUA_REGISTRYINDEX, C.CString(tname))
}