Golang C.malloc函數代碼示例

// MakeOIDBytes makes an OID encapsulating a byte slice. Note that it does not
// duplicate the data, but rather it points to it directly.
func (lib *Lib) MakeOIDBytes(data []byte) (*OID, error) {
	oid := lib.NewOID()

	s := C.malloc(C.gss_OID_size) // s for struct
	if s == nil {
		return nil, ErrMallocFailed
	}
	C.memset(s, 0, C.gss_OID_size)

	l := C.size_t(len(data))
	e := C.malloc(l) // c for contents
	if e == nil {
		return nil, ErrMallocFailed
	}
	C.memmove(e, (unsafe.Pointer)(&data[0]), l)

	oid.C_gss_OID = C.gss_OID(s)
	oid.alloc = allocMalloc

	// because of the alignment issues I can't access o.oid's fields from go,
	// so invoking a C function to do the same as:
	// oid.C_gss_OID.length = l
	// oid.C_gss_OID.elements = c
	C.helper_gss_OID_desc_set_elements(oid.C_gss_OID, C.OM_uint32(l), e)

	return oid, nil
}

func NewTrailDBConstructor(path string, ofields ...string) (*TrailDBConstructor, error) {
	cons := C.tdb_cons_init()
	cpath := C.CString(path)
	defer C.free(unsafe.Pointer(cpath))

	var ofield_p *C.char
	ptrSize := unsafe.Sizeof(ofield_p)

	// Allocate the char** list.
	ptr := C.malloc(C.size_t(len(ofields)) * C.size_t(ptrSize))
	defer C.free(ptr)

	// Assign each byte slice to its appropriate offset.
	for i := 0; i < len(ofields); i++ {
		element := (**C.char)(unsafe.Pointer(uintptr(ptr) + uintptr(i)*ptrSize))
		cofield := C.CString(ofields[i])
		defer C.free(unsafe.Pointer(cofield))
		*element = cofield
	}

	if err := C.tdb_cons_open(cons, cpath, (**C.char)(ptr), C.uint64_t(len(ofields))); err != 0 {
		return nil, errors.New(errToString(err))
	}
	return &TrailDBConstructor{
		cons:         cons,
		path:         path,
		ofields:      ofields,
		valueLengths: make([]C.uint64_t, len(ofields)),
		valuePtr:     C.malloc(C.size_t(len(ofields)) * C.size_t(ptrSize)),
	}, nil
}

func New(seedHash []byte, block pow.Block) (*Ethash, error) {
	params := new(C.ethash_params)
	n, err := blockNum(block)
	if err != nil {
		return &Ethash{}, err
	}
	C.ethash_params_init(params, C.uint32_t(n))
	log.Println("Params", params)

	var mem unsafe.Pointer
	mem = C.malloc(C.size_t(params.full_size))

	cache := new(C.ethash_cache)
	C.ethash_cache_init(cache, mem)

	log.Println("making full data")
	start := time.Now()
	C.ethash_compute_full_data(mem, params, cache)
	log.Println("took:", time.Since(start))

	var hash *C.uint8_t
	hash = (*C.uint8_t)(C.malloc(32))

	return &Ethash{
		turbo:  false,
		params: params,
		cache:  cache,
		mem:    mem,
		hash:   hash,
	}, nil
}

// The C side of things will still need to allocate memory, due to the slices.
// Assumes Configuration is valid.
func (config *Configuration) _CGO() *C.CGO_Configuration {
	INFO.Println("Converting Config: ", config)
	size := C.size_t(unsafe.Sizeof(C.CGO_Configuration{}))
	c := (*C.CGO_Configuration)(C.malloc(size))

	// Need to convert each IceServer struct individually.
	total := len(config.IceServers)
	if total > 0 {
		sizeof := unsafe.Sizeof(C.CGO_IceServer{})
		cServers := unsafe.Pointer(C.malloc(C.size_t(sizeof * uintptr(total))))
		ptr := uintptr(cServers)
		for _, server := range config.IceServers {
			*(*C.CGO_IceServer)(unsafe.Pointer(ptr)) = server._CGO()
			ptr += sizeof
		}
		c.iceServers = (*C.CGO_IceServer)(cServers)
	}
	c.numIceServers = C.int(total)

	// c.iceServers = (*C.CGO_IceServer)(unsafe.Pointer(&config.IceServers))
	c.iceTransportPolicy = C.int(config.IceTransportPolicy)
	c.bundlePolicy = C.int(config.BundlePolicy)
	// [ED] c.RtcpMuxPolicy = C.int(config.RtcpMuxPolicy)
	c.peerIdentity = C.CString(config.PeerIdentity)
	// [ED] c.Certificates = config.Certificates
	// [ED] c.IceCandidatePoolSize = C.int(config.IceCandidatePoolSize)
	return c
}

func LaunchKernel(f Function, gridDimX, gridDimY, gridDimZ int, blockDimX, blockDimY, blockDimZ int, sharedMemBytes int, stream Stream, kernelParams []unsafe.Pointer) {

	// Since Go 1.6, a cgo argument cannot have a Go pointer to Go pointer,
	// so we copy the argument values go C memory first.
	argv := C.malloc(C.size_t(len(kernelParams) * pointerSize))
	argp := C.malloc(C.size_t(len(kernelParams) * pointerSize))
	defer C.free(argv)
	defer C.free(argp)
	for i := range kernelParams {
		*((*unsafe.Pointer)(offset(argp, i))) = offset(argv, i)       // argp[i] = &argv[i]
		*((*uint64)(offset(argv, i))) = *((*uint64)(kernelParams[i])) // argv[i] = *kernelParams[i]
	}

	err := Result(C.cuLaunchKernel(
		C.CUfunction(unsafe.Pointer(uintptr(f))),
		C.uint(gridDimX),
		C.uint(gridDimY),
		C.uint(gridDimZ),
		C.uint(blockDimX),
		C.uint(blockDimY),
		C.uint(blockDimZ),
		C.uint(sharedMemBytes),
		C.CUstream(unsafe.Pointer(uintptr(stream))),
		(*unsafe.Pointer)(argp),
		(*unsafe.Pointer)(unsafe.Pointer(uintptr(0)))))
	if err != SUCCESS {
		panic(err)
	}
}

//////////////////////////
//      寫入接口        //
//////////////////////////
func Store(table *Table,
	primary_key string, // key after encode
	timestamp int64,
	index_list []Index,
	data_list []string) error {
	var c_request C.mdt_store_request_t
	var c_response C.mdt_store_response_t

	// convert request
	c_request.primary_key.data = C.CString(primary_key)
	c_request.primary_key.size = C.size_t(len(primary_key))
	c_request.timestamp = C.int64_t(timestamp)

	c_request.index_list = nil
	c_request.index_list_len = C.size_t(len(index_list))
	c_request.index_list = (*C.mdt_index_t)(C.malloc(32 * c_request.index_list_len))
	c_index_list := (*[1 << 30]C.mdt_index_t)(unsafe.Pointer(c_request.index_list))
	for i := C.size_t(0); i < c_request.index_list_len; i++ {
		c_index_list[i].index_name.data = C.CString(index_list[i].IndexName)
		c_index_list[i].index_name.size = C.size_t(len(index_list[i].IndexName))
		c_index_list[i].index_key.data = C.CString(index_list[i].IndexKey)
		c_index_list[i].index_key.size = C.size_t(len(index_list[i].IndexKey))
	}

	// new vector write interface
	c_request.data_list = nil
	c_request.data_list_len = C.size_t(data_list)
	c_request.data_list = (*C.mdt_slice_t)(C.malloc(16 * c_request.data_list_len))
	c_data_list := (*[1 << 30]C.mdt_slice_t)(unsafe.Pointer(c_request.data_list))
	for i := C.size_t(0); i < c_request.data_list_len; data_i++ {
		c_data_list[i].data = C.CString(data_list[i])
		c_data_list[i].size = C.size_t(len(data_list[i]))
	}
	// old write interface
	//c_request.data.data = C.CString(data)
	//c_request.data.size = C.size_t(len(data))

	// invoke C API
	C.mdt_store(table.rep, &c_request, &c_response, nil, nil)

	// convert result
	err := int(c_response.error)

	// free request memory
	C.free(unsafe.Pointer(c_request.primary_key.data))

	for i := C.size_t(0); i < c_request.index_list_len; i++ {
		C.free(unsafe.Pointer(c_index_list[i].index_name.data))
		C.free(unsafe.Pointer(c_index_list[i].index_key.data))
	}
	C.free(unsafe.Pointer(c_request.index_list))

	for i := C.size_t(0); i < c_request.data_list_len; i++ {
		C.free(unsafe.Pointer(c_data_list[i].data))
	}
	C.free(unsafe.Pointer(c_request.data_list))
	//C.free(unsafe.Pointer(c_request.data.data))

	return GetError(err)
}

func generateCmac(key []byte, msg []byte) []byte {
	if len(key) != 16 {
		panic("Invalid length.")
	}

	cMac := (*C.uchar)(C.malloc(16))
	defer C.free(unsafe.Pointer(cMac))

	var msgStart *C.uchar
	if len(msg) > 0 {
		msgStart = (*C.uchar)(&msg[0])
	} else {
		// Avoid indexing into empty slice/C array.
		msgStart = (*C.uchar)(C.malloc(1))
		defer C.free(unsafe.Pointer(msgStart))
	}

	C.AES_CMAC(
		(*C.uchar)(&key[0]),
		msgStart,
		C.int(len(msg)),
		cMac)

	return C.GoBytes(unsafe.Pointer(cMac), 16)
}

// Append the map `pairs` to the omap `oid`
func (ioctx *IOContext) SetOmap(oid string, pairs map[string][]byte) error {
	c_oid := C.CString(oid)
	defer C.free(unsafe.Pointer(c_oid))

	var s C.size_t
	var c *C.char
	ptrSize := unsafe.Sizeof(c)

	c_keys := C.malloc(C.size_t(len(pairs)) * C.size_t(ptrSize))
	c_values := C.malloc(C.size_t(len(pairs)) * C.size_t(ptrSize))
	c_lengths := C.malloc(C.size_t(len(pairs)) * C.size_t(unsafe.Sizeof(s)))

	defer C.free(unsafe.Pointer(c_keys))
	defer C.free(unsafe.Pointer(c_values))
	defer C.free(unsafe.Pointer(c_lengths))

	i := 0
	for key, value := range pairs {
		// key
		c_key_ptr := (**C.char)(unsafe.Pointer(uintptr(c_keys) + uintptr(i)*ptrSize))
		*c_key_ptr = C.CString(key)
		defer C.free(unsafe.Pointer(*c_key_ptr))

		// value and its length
		c_value_ptr := (**C.char)(unsafe.Pointer(uintptr(c_values) + uintptr(i)*ptrSize))

		var c_length C.size_t
		if len(value) > 0 {
			*c_value_ptr = (*C.char)(unsafe.Pointer(&value[0]))
			c_length = C.size_t(len(value))
		} else {
			*c_value_ptr = nil
			c_length = C.size_t(0)
		}

		c_length_ptr := (*C.size_t)(unsafe.Pointer(uintptr(c_lengths) + uintptr(i)*ptrSize))
		*c_length_ptr = c_length

		i++
	}

	op := C.rados_create_write_op()
	C.rados_write_op_omap_set(
		op,
		(**C.char)(c_keys),
		(**C.char)(c_values),
		(*C.size_t)(c_lengths),
		C.size_t(len(pairs)))

	ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
	C.rados_release_write_op(op)

	if ret == 0 {
		return nil
	} else {
		return RadosError(int(ret))
	}
}

func GetNthAircraftModel(index int) (fileName, path string) {
	nameBuf := (*C.char)(C.malloc(256))
	defer C.free(unsafe.Pointer(nameBuf))
	pathBuf := (*C.char)(C.malloc(512))
	defer C.free(unsafe.Pointer(pathBuf))
	C.XPLMGetNthAircraftModel((C.int)(index), nameBuf, pathBuf)
	fileName = C.GoString(nameBuf)
	path = C.GoString(pathBuf)
	return
}

func Spawn(loop *Loop, options ProcessOptions) (err error) {
	if loop == nil {
		loop = DefaultLoop()
	}

	var opt C.uv_process_options_t
	defer func() {
		/*
			C.free(unsafe.Pointer(opt.file))
			if len(options.Args) > 0 {
				for n := 0; n < len(options.Args); n++ {
					C.free(unsafe.Pointer(((*[1<<24]*C.char)(unsafe.Pointer(&opt.args)))[n]))
				}
				C.free(unsafe.Pointer(opt.args))
			}
			if len(options.Env) > 0 {
				for n := 0; n < len(options.Env); n++ {
					C.free(unsafe.Pointer(((*[1<<24]*C.char)(unsafe.Pointer(&opt.env)))[n]))
				}
				C.free(unsafe.Pointer(opt.env))
			}
			C.free(unsafe.Pointer(opt.cwd))
		*/
	}()
	if len(options.File) > 0 {
		opt.file = C.CString(options.File)
	}
	if len(options.Args) > 0 {
		opt.args = (**C.char)(C.malloc(C.size_t(4 * (len(options.Args) + 1))))
		for n := 0; n < len(options.Args); n++ {
			((*[1 << 24]*C.char)(unsafe.Pointer(&opt.args)))[n] = C.CString(options.Args[n])
		}
		((*[1 << 24]*C.char)(unsafe.Pointer(&opt.args)))[len(options.Args)] = nil
	}
	if len(options.Env) > 0 {
		opt.env = (**C.char)(C.malloc(C.size_t(4 * (len(options.Env) + 1))))
		for n := 0; n < len(options.Args); n++ {
			((*[1 << 24]*C.char)(unsafe.Pointer(&opt.env)))[n] = C.CString(options.Args[n])
		}
		((*[1 << 24]*C.char)(unsafe.Pointer(&opt.env)))[len(options.Args)] = nil
	}
	if len(options.Cwd) > 0 {
		opt.cwd = C.CString(options.Cwd)
	}
	// TODO: uv_stdio_container_t

	var p C.uv_process_t
	p.data = unsafe.Pointer(&callback_info{exit_cb: options.Exit_cb})
	r := uv_spawn(loop.l, &p, opt)
	if r != 0 {
		return loop.LastError().Error()
	}
	return nil
}

func test6390(t *testing.T) {
	p1 := C.malloc(1024)
	if p1 == nil {
		t.Fatalf("C.malloc(1024) returned nil")
	}
	p2 := C.malloc(0)
	if p2 == nil {
		t.Fatalf("C.malloc(0) returned nil")
	}
	C.free(p1)
	C.free(p2)
}

// List clients that have locked the named object lock and information about the lock.
// The number of bytes required in each buffer is put in the corresponding size out parameter.
// If any of the provided buffers are too short, -ERANGE is returned after these sizes are filled in.
func (ioctx *IOContext) ListLockers(oid, name string) (*LockInfo, error) {
	c_oid := C.CString(oid)
	c_name := C.CString(name)

	c_tag := (*C.char)(C.malloc(C.size_t(1024)))
	c_clients := (*C.char)(C.malloc(C.size_t(1024)))
	c_cookies := (*C.char)(C.malloc(C.size_t(1024)))
	c_addrs := (*C.char)(C.malloc(C.size_t(1024)))

	var c_exclusive C.int
	c_tag_len := C.size_t(1024)
	c_clients_len := C.size_t(1024)
	c_cookies_len := C.size_t(1024)
	c_addrs_len := C.size_t(1024)

	defer C.free(unsafe.Pointer(c_oid))
	defer C.free(unsafe.Pointer(c_name))
	defer C.free(unsafe.Pointer(c_tag))
	defer C.free(unsafe.Pointer(c_clients))
	defer C.free(unsafe.Pointer(c_cookies))
	defer C.free(unsafe.Pointer(c_addrs))

	ret := C.rados_list_lockers(
		ioctx.ioctx,
		c_oid,
		c_name,
		&c_exclusive,
		c_tag,
		&c_tag_len,
		c_clients,
		&c_clients_len,
		c_cookies,
		&c_cookies_len,
		c_addrs,
		&c_addrs_len)

	splitCString := func(items *C.char, itemsLen C.size_t) []string {
		currLen := 0
		clients := []string{}
		for currLen < int(itemsLen) {
			client := C.GoString(C.nextChunk(&items))
			clients = append(clients, client)
			currLen += len(client) + 1
		}
		return clients
	}

	if ret < 0 {
		return nil, RadosError(int(ret))
	} else {
		return &LockInfo{int(ret), c_exclusive == 1, C.GoString(c_tag), splitCString(c_clients, c_clients_len), splitCString(c_cookies, c_cookies_len), splitCString(c_addrs, c_addrs_len)}, nil
	}
}

func generateSubkey(key []byte) (k1 []byte, k2 []byte) {
	if len(key) != 16 {
		panic("Invalid length.")
	}

	cK1 := (*C.uchar)(C.malloc(16))
	defer C.free(unsafe.Pointer(cK1))

	cK2 := (*C.uchar)(C.malloc(16))
	defer C.free(unsafe.Pointer(cK2))

	C.generate_subkey((*C.uchar)(&key[0]), cK1, cK2)

	return C.GoBytes(unsafe.Pointer(cK1), 16), C.GoBytes(unsafe.Pointer(cK2), 16)
}

func doFinish(call rpc.ClientCall, numResults int) (C.SwiftByteArrayArray, error) {
	// Have all the results be decoded into *vdl.Value.
	resultPtrs := make([]interface{}, numResults)
	for i := 0; i < numResults; i++ {
		value := new(vdl.Value)
		resultPtrs[i] = &value
	}
	if err := call.Finish(resultPtrs...); err != nil {
		// Invocation error.
		return EmptySwiftByteArrayArray(), err
	}

	// VOM-encode the results. Note in the future we'll want a pathway where we can get the original VOM results
	// from finish so we don't end up wasting CPU & memory here.

	// Prepare the byte array array that can be accessed from Swift via C.malloc
	vomResultsMemory := C.malloc(C.size_t(numResults * int(C.sizeofSwiftByteArray)))
	// Make that malloc'd memory available as a slice to Go.
	vomResultsPtrsHdr := reflect.SliceHeader{
		Data: uintptr(vomResultsMemory),
		Len:  numResults,
		Cap:  numResults,
	}
	vomResults := *(*[]C.SwiftByteArray)(unsafe.Pointer(&vomResultsPtrsHdr))
	// Create the C Struct to return that encapsulates our byte array array
	var cVomResults C.SwiftByteArrayArray
	cVomResults.length = C._GoUint64(numResults)
	cVomResults.data = (*C.SwiftByteArray)(vomResultsMemory)

	// For each result, VOM encode into a byte array that we stick into the returned struct
	for i, resultPtr := range resultPtrs {
		// Remove the pointer from the result.  Simply *resultPtr doesn't work
		// as resultPtr is of type interface{}.
		result := interface{}(sutil.DerefOrDie(resultPtr))
		var vomResult []byte
		var err error
		if vomResult, err = vom.Encode(result); err != nil {
			return EmptySwiftByteArrayArray(), err
		}
		cVomResultCopy := C.malloc(C.size_t(len(vomResult)))
		C.memcpy(cVomResultCopy, unsafe.Pointer(&vomResult[0]), C.size_t(len(vomResult)))
		var cVomResult C.SwiftByteArray
		cVomResult.length = C._GoUint64(len(vomResult))
		cVomResult.data = cVomResultCopy
		vomResults[i] = cVomResult
	}
	return cVomResults, nil
}

func GetShaderInfoLog(s Shader) string {
	infoLen := GetShaderi(s, INFO_LOG_LENGTH)
	buf := C.malloc(C.size_t(infoLen))
	defer C.free(buf)
	C.glGetShaderInfoLog(s.c(), C.GLsizei(infoLen), nil, (*C.GLchar)(buf))
	return C.GoString((*C.char)(buf))
}