gojs

Documentation

Index

• Variables
• func GetLastEventArgs(ctx context.Context) []interface{}
• func LoadValue(ctx context.Context, ref goos.Ref) interface{}
• func WriteArgsAndEnviron(mod api.Module) (argc, argv uint32, err error)
• type Errno
  • func ToErrno(err error) *Errno
  • func (e *Errno) Error() string
• type State
  • func NewState(config *config.Config) *State
  • func (s *State) Get(propertyKey string) interface{}
• type StateKey

Variables

var (
	// ErrnoAcces Permission denied.
	ErrnoAcces = &Errno{"EACCES"}
	// ErrnoAgain Resource unavailable, or operation would block.
	ErrnoAgain = &Errno{"EAGAIN"}
	// ErrnoBadf Bad file descriptor.
	ErrnoBadf = &Errno{"EBADF"}
	// ErrnoExist File exists.
	ErrnoExist = &Errno{"EEXIST"}
	// ErrnoFault Bad address.
	ErrnoFault = &Errno{"EFAULT"}
	// ErrnoIntr Interrupted function.
	ErrnoIntr = &Errno{"EINTR"}
	// ErrnoInval Invalid argument.
	ErrnoInval = &Errno{"EINVAL"}
	// ErrnoIo I/O error.
	ErrnoIo = &Errno{"EIO"}
	// ErrnoIsdir Is a directory.
	ErrnoIsdir = &Errno{"EISDIR"}
	// ErrnoLoop Too many levels of symbolic links.
	ErrnoLoop = &Errno{"ELOOP"}
	// ErrnoNametoolong Filename too long.
	ErrnoNametoolong = &Errno{"ENAMETOOLONG"}
	// ErrnoNoent No such file or directory.
	ErrnoNoent = &Errno{"ENOENT"}
	// ErrnoNosys function not supported.
	ErrnoNosys = &Errno{"ENOSYS"}
	// ErrnoNotdir Not a directory or a symbolic link to a directory.
	ErrnoNotdir = &Errno{"ENOTDIR"}
	// ErrnoNotempty Directory not empty.
	ErrnoNotempty = &Errno{"ENOTEMPTY"}
	// ErrnoNotsup Not supported, or operation not supported on socket.
	ErrnoNotsup = &Errno{"ENOTSUP"}
	// ErrnoPerm Operation not permitted.
	ErrnoPerm = &Errno{"EPERM"}
	// ErrnoRofs read-only file system.
	ErrnoRofs = &Errno{"EROFS"}
)

This order match constants from wasi_snapshot_preview1.ErrnoSuccess for easier maintenance.

var ClearTimeoutEvent = goarch.NewFunc(custom.NameRuntimeClearTimeoutEvent, clearTimeoutEvent)

ClearTimeoutEvent implements runtime.clearTimeoutEvent which supports runtime.notetsleepg used by runtime.signal_recv.

See https://github.com/golang/go/blob/go1.20/src/runtime/sys_wasm.s#L129

var CopyBytesToGo = goos.NewFunc(custom.NameSyscallCopyBytesToGo, copyBytesToGo)

CopyBytesToGo copies a JavaScript managed byte array to linear memory. For example, this is used to read an HTTP response body.

Results

• n is the count of bytes written.
• ok is false if the src was not a uint8Array.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L569 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L437-L449

var CopyBytesToJS = goos.NewFunc(custom.NameSyscallCopyBytesToJS, copyBytesToJS)

CopyBytesToJS copies linear memory to a JavaScript managed byte array. For example, this is used to read an HTTP request body.

Results

• n is the count of bytes written.
• ok is false if the dst was not a uint8Array.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L583 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L438-L448

var Debug = goarch.StubFunction(custom.NameDebug)

Debug has unknown use, so stubbed.

See https://github.com/golang/go/blob/go1.20/src/cmd/link/internal/wasm/asm.go#L131-L136

var FinalizeRef = goos.NewFunc(custom.NameSyscallFinalizeRef, finalizeRef)

FinalizeRef implements js.finalizeRef, which is used as a runtime.SetFinalizer on the given reference.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L61

var GetRandomData = goarch.NewFunc(custom.NameRuntimeGetRandomData, getRandomData)

GetRandomData implements runtime.getRandomData, which initializes the seed for runtime.fastrand.

See https://github.com/golang/go/blob/go1.20/src/runtime/sys_wasm.s#L133

var NaN = math.NaN()

var Nanotime1 = goarch.NewFunc(custom.NameRuntimeNanotime1, nanotime1)

Nanotime1 implements runtime.nanotime which supports time.Since.

See https://github.com/golang/go/blob/go1.20/src/runtime/sys_wasm.s#L117

var ResetMemoryDataView = goarch.NewFunc(custom.NameRuntimeResetMemoryDataView, resetMemoryDataView)

ResetMemoryDataView signals wasm.OpcodeMemoryGrow happened, indicating any cached view of memory should be reset.

See https://github.com/golang/go/blob/go1.20/src/runtime/mem_js.go#L82

var ScheduleTimeoutEvent = goarch.NewFunc(custom.NameRuntimeScheduleTimeoutEvent, scheduleTimeoutEvent)

ScheduleTimeoutEvent implements runtime.scheduleTimeoutEvent which supports runtime.notetsleepg used by runtime.signal_recv.

Unlike other most functions prefixed by "runtime.", this both launches a goroutine and invokes code compiled into wasm "resume".

See https://github.com/golang/go/blob/go1.20/src/runtime/sys_wasm.s#L125

var StringVal = goos.NewFunc(custom.NameSyscallStringVal, stringVal)

StringVal implements js.stringVal, which is used to load the string for `js.ValueOf(x)`. For example, this is used when setting HTTP headers.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L212 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L305-L308

var ValueCall = goos.NewFunc(custom.NameSyscallValueCall, valueCall)

ValueCall implements js.valueCall, which is used to call a js.Value function by name, e.g. `document.Call("createElement", "div")`.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L394 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L343-L358

var ValueDelete = goarch.StubFunction(custom.NameSyscallValueDelete)

ValueDelete is stubbed as it isn't used in Go's main source tree.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L321

var ValueGet = goos.NewFunc(custom.NameSyscallValueGet, valueGet)

ValueGet implements js.valueGet, which is used to load a js.Value property by name, e.g. `v.Get("address")`. Notably, this is used by js.handleEvent to get the pending event.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L295 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L311-L316

var ValueIndex = goos.NewFunc(custom.NameSyscallValueIndex, valueIndex)

ValueIndex implements js.valueIndex, which is used to load a js.Value property by index, e.g. `v.Index(0)`. Notably, this is used by js.handleEvent to read event arguments

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L334 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L331-L334

var ValueInstanceOf = goarch.StubFunction(custom.NameSyscallValueInstanceOf)

ValueInstanceOf is stubbed as it isn't used in Go's main source tree.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L543

var ValueInvoke = goarch.StubFunction(custom.NameSyscallValueInvoke)

ValueInvoke is stubbed as it isn't used in Go's main source tree.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L413

var ValueLength = goos.NewFunc(custom.NameSyscallValueLength, valueLength)

ValueLength implements js.valueLength, which is used to load the length property of a value, e.g. `array.length`.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L372 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L395-L398

var ValueLoadString = goos.NewFunc(custom.NameSyscallValueLoadString, valueLoadString)

ValueLoadString implements js.valueLoadString, which is used copy a string value for `o.String()`.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L533 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L409-L413

var ValueNew = goos.NewFunc(custom.NameSyscallValueNew, valueNew)

ValueNew implements js.valueNew, which is used to call a js.Value, e.g. `array.New(2)`.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L432 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L378-L392

var ValuePrepareString = goos.NewFunc(custom.NameSyscallValuePrepareString, valuePrepareString)

ValuePrepareString implements js.valuePrepareString, which is used to load the string for `o.String()` (via js.jsString) for string, boolean and number types. Notably, http.Transport uses this in RoundTrip to coerce the URL to a string.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L531 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L401-L406

var ValueSet = goos.NewFunc(custom.NameSyscallValueSet, valueSet)

ValueSet implements js.valueSet, which is used to store a js.Value property by name, e.g. `v.Set("address", a)`. Notably, this is used by js.handleEvent set the event result.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L309 and https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L318-L322

var ValueSetIndex = goarch.StubFunction(custom.NameSyscallValueSetIndex)

ValueSetIndex is stubbed as it is only used for js.ValueOf when the input is []interface{}, which doesn't appear to occur in Go's source tree.

See https://github.com/golang/go/blob/go1.20/src/syscall/js/js.go#L348

var Walltime = goarch.NewFunc(custom.NameRuntimeWalltime, walltime)

Walltime implements runtime.walltime which supports time.Now.

See https://github.com/golang/go/blob/go1.20/src/runtime/sys_wasm.s#L121

var WasmExit = goarch.NewFunc(custom.NameRuntimeWasmExit, wasmExit)

WasmExit implements runtime.wasmExit which supports runtime.exit.

See https://github.com/golang/go/blob/go1.20/src/runtime/sys_wasm.go#L24

var WasmWrite = goarch.NewFunc(custom.NameRuntimeWasmWrite, wasmWrite)

WasmWrite implements runtime.wasmWrite which supports runtime.write and runtime.writeErr. This implements `println`.

See https://github.com/golang/go/blob/go1.20/src/runtime/os_js.go#L30

Functions

func GetLastEventArgs

func GetLastEventArgs(ctx context.Context) []interface{}

GetLastEventArgs implements goos.GetLastEventArgs

func LoadValue

func LoadValue(ctx context.Context, ref goos.Ref) interface{}

LoadValue reads up to 8 bytes at the memory offset `addr` to return the value written by storeValue.

See https://github.com/golang/go/blob/go1.20/misc/wasm/wasm_exec.js#L122-L133

func WriteArgsAndEnviron

func WriteArgsAndEnviron(mod api.Module) (argc, argv uint32, err error)

WriteArgsAndEnviron writes arguments and environment variables to memory, so they can be read by main, Go compiles as the function export "run".

Types

type Errno

type Errno struct {
	// contains filtered or unexported fields
}

Errno is a (GOARCH=wasm) error, which must match a key in mapJSError.

See https://github.com/golang/go/blob/go1.20/src/syscall/tables_js.go#L371-L494

func ToErrno

func ToErrno(err error) *Errno

ToErrno maps I/O errors as the message must be the code, ex. "EINVAL", not the message, e.g. "invalid argument".

func (*Errno) Error

func (e *Errno) Error() string

Error implements error.

type State

type State struct {
	// contains filtered or unexported fields
}

State holds state used by the "go" imports used by gojs. Note: This is module-scoped.

func NewState

func NewState(config *config.Config) *State

func (*State) Get

func (s *State) Get(propertyKey string) interface{}

Get implements the same method as documented on goos.GetFunction

type StateKey

type StateKey struct{}

StateKey is a context.Context Value key. The value must be a state pointer.