diff options
Diffstat (limited to 'jsre/jsre.go')
-rw-r--r-- | jsre/jsre.go | 235 |
1 files changed, 86 insertions, 149 deletions
diff --git a/jsre/jsre.go b/jsre/jsre.go index a6dd117a3..3d648f02c 100644 --- a/jsre/jsre.go +++ b/jsre/jsre.go @@ -19,9 +19,7 @@ It provides some helper functions to - bind native go objects */ type JSRE struct { - assetPath string - vm *otto.Otto - + assetPath string evalQueue chan *evalReq stopEventLoop chan bool loopWg sync.WaitGroup @@ -35,68 +33,37 @@ type jsTimer struct { call otto.FunctionCall } -// evalResult is a structure to store the result of any serialized vm execution -type evalResult struct { - result otto.Value - err error -} - -// evalReq is a serialized vm execution request put in evalQueue and processed by runEventLoop +// evalReq is a serialized vm execution request processed by runEventLoop. type evalReq struct { - fn func(res *evalResult) + fn func(vm *otto.Otto) done chan bool - res evalResult } // runtime must be stopped with Stop() after use and cannot be used after stopping func New(assetPath string) *JSRE { re := &JSRE{ - assetPath: assetPath, - vm: otto.New(), + assetPath: assetPath, + evalQueue: make(chan *evalReq), + stopEventLoop: make(chan bool), } - - // load prettyprint func definition - re.vm.Run(pp_js) - re.vm.Set("loadScript", re.loadScript) - - re.evalQueue = make(chan *evalReq) - re.stopEventLoop = make(chan bool) re.loopWg.Add(1) go re.runEventLoop() - + re.Compile("pp.js", pp_js) // load prettyprint func definition + re.Set("loadScript", re.loadScript) return re } -// this function runs a piece of JS code either in a serialized way (when useEQ is true) or instantly, circumventing the evalQueue -func (self *JSRE) run(src interface{}, useEQ bool) (value otto.Value, err error) { - if useEQ { - done := make(chan bool) - req := &evalReq{ - fn: func(res *evalResult) { - res.result, res.err = self.vm.Run(src) - }, - done: done, - } - self.evalQueue <- req - <-done - return req.res.result, req.res.err - } else { - return self.vm.Run(src) - } -} +// This function runs the main event loop from a goroutine that is started +// when JSRE is created. Use Stop() before exiting to properly stop it. +// The event loop processes vm access requests from the evalQueue in a +// serialized way and calls timer callback functions at the appropriate time. -/* -This function runs the main event loop from a goroutine that is started - when JSRE is created. Use Stop() before exiting to properly stop it. -The event loop processes vm access requests from the evalQueue in a - serialized way and calls timer callback functions at the appropriate time. - -Exported functions always access the vm through the event queue. You can - call the functions of the otto vm directly to circumvent the queue. These - functions should be used if and only if running a routine that was already - called from JS through an RPC call. -*/ +// Exported functions always access the vm through the event queue. You can +// call the functions of the otto vm directly to circumvent the queue. These +// functions should be used if and only if running a routine that was already +// called from JS through an RPC call. func (self *JSRE) runEventLoop() { + vm := otto.New() registry := map[*jsTimer]*jsTimer{} ready := make(chan *jsTimer) @@ -143,10 +110,10 @@ func (self *JSRE) runEventLoop() { } return otto.UndefinedValue() } - self.vm.Set("setTimeout", setTimeout) - self.vm.Set("setInterval", setInterval) - self.vm.Set("clearTimeout", clearTimeout) - self.vm.Set("clearInterval", clearTimeout) + vm.Set("setTimeout", setTimeout) + vm.Set("setInterval", setInterval) + vm.Set("clearTimeout", clearTimeout) + vm.Set("clearInterval", clearTimeout) var waitForCallbacks bool @@ -166,8 +133,7 @@ loop: arguments = make([]interface{}, 1) } arguments[0] = timer.call.ArgumentList[0] - _, err := self.vm.Call(`Function.call.call`, nil, arguments...) - + _, err := vm.Call(`Function.call.call`, nil, arguments...) if err != nil { fmt.Println("js error:", err, arguments) } @@ -179,10 +145,10 @@ loop: break loop } } - case evalReq := <-self.evalQueue: + case req := <-self.evalQueue: // run the code, send the result back - evalReq.fn(&evalReq.res) - close(evalReq.done) + req.fn(vm) + close(req.done) if waitForCallbacks && (len(registry) == 0) { break loop } @@ -201,6 +167,14 @@ loop: self.loopWg.Done() } +// do schedules the given function on the event loop. +func (self *JSRE) do(fn func(*otto.Otto)) { + done := make(chan bool) + req := &evalReq{fn, done} + self.evalQueue <- req + <-done +} + // stops the event loop before exit, optionally waits for all timers to expire func (self *JSRE) Stop(waitForCallbacks bool) { self.stopEventLoop <- waitForCallbacks @@ -210,119 +184,78 @@ func (self *JSRE) Stop(waitForCallbacks bool) { // Exec(file) loads and runs the contents of a file // if a relative path is given, the jsre's assetPath is used func (self *JSRE) Exec(file string) error { - return self.exec(common.AbsolutePath(self.assetPath, file), true) -} - -// circumvents the eval queue, see runEventLoop -func (self *JSRE) execWithoutEQ(file string) error { - return self.exec(common.AbsolutePath(self.assetPath, file), false) -} - -func (self *JSRE) exec(path string, useEQ bool) error { - code, err := ioutil.ReadFile(path) + code, err := ioutil.ReadFile(common.AbsolutePath(self.assetPath, file)) if err != nil { return err } - _, err = self.run(code, useEQ) + self.do(func(vm *otto.Otto) { _, err = vm.Run(code) }) return err } -// assigns value v to a variable in the JS environment -func (self *JSRE) Bind(name string, v interface{}) (err error) { - self.Set(name, v) - return +// Bind assigns value v to a variable in the JS environment +// This method is deprecated, use Set. +func (self *JSRE) Bind(name string, v interface{}) error { + return self.Set(name, v) } -// runs a piece of JS code -func (self *JSRE) Run(code string) (otto.Value, error) { - return self.run(code, true) +// Run runs a piece of JS code. +func (self *JSRE) Run(code string) (v otto.Value, err error) { + self.do(func(vm *otto.Otto) { v, err = vm.Run(code) }) + return v, err } -// returns the value of a variable in the JS environment -func (self *JSRE) Get(ns string) (otto.Value, error) { - done := make(chan bool) - req := &evalReq{ - fn: func(res *evalResult) { - res.result, res.err = self.vm.Get(ns) - }, - done: done, - } - self.evalQueue <- req - <-done - return req.res.result, req.res.err +// Get returns the value of a variable in the JS environment. +func (self *JSRE) Get(ns string) (v otto.Value, err error) { + self.do(func(vm *otto.Otto) { v, err = vm.Get(ns) }) + return v, err } -// assigns value v to a variable in the JS environment -func (self *JSRE) Set(ns string, v interface{}) error { - done := make(chan bool) - req := &evalReq{ - fn: func(res *evalResult) { - res.err = self.vm.Set(ns, v) - }, - done: done, - } - self.evalQueue <- req - <-done - return req.res.err +// Set assigns value v to a variable in the JS environment. +func (self *JSRE) Set(ns string, v interface{}) (err error) { + self.do(func(vm *otto.Otto) { err = vm.Set(ns, v) }) + return err } -/* -Executes a JS script from inside the currently executing JS code. -Should only be called from inside an RPC routine. -*/ +// loadScript executes a JS script from inside the currently executing JS code. func (self *JSRE) loadScript(call otto.FunctionCall) otto.Value { file, err := call.Argument(0).ToString() if err != nil { + // TODO: throw exception + return otto.FalseValue() + } + file = common.AbsolutePath(self.assetPath, file) + source, err := ioutil.ReadFile(file) + if err != nil { + // TODO: throw exception return otto.FalseValue() } - if err := self.execWithoutEQ(file); err != nil { // loadScript is only called from inside js + if _, err := compileAndRun(call.Otto, file, source); err != nil { + // TODO: throw exception fmt.Println("err:", err) return otto.FalseValue() } - + // TODO: return evaluation result return otto.TrueValue() } -// uses the "prettyPrint" JS function to format a value +// PrettyPrint writes v to standard output. func (self *JSRE) PrettyPrint(v interface{}) (val otto.Value, err error) { var method otto.Value - v, err = self.ToValue(v) - if err != nil { - return - } - method, err = self.vm.Get("prettyPrint") - if err != nil { - return - } - return method.Call(method, v) -} - -// creates an otto value from a go type (serialized version) -func (self *JSRE) ToValue(v interface{}) (otto.Value, error) { - done := make(chan bool) - req := &evalReq{ - fn: func(res *evalResult) { - res.result, res.err = self.vm.ToValue(v) - }, - done: done, - } - self.evalQueue <- req - <-done - return req.res.result, req.res.err -} - -// creates an otto value from a go type (non-serialized version) -func (self *JSRE) ToVal(v interface{}) otto.Value { - - result, err := self.vm.ToValue(v) - if err != nil { - fmt.Println("Value unknown:", err) - return otto.UndefinedValue() - } - return result + self.do(func(vm *otto.Otto) { + val, err = vm.ToValue(v) + if err != nil { + return + } + method, err = vm.Get("prettyPrint") + if err != nil { + return + } + val, err = method.Call(method, val) + }) + return val, err } -// evaluates JS function and returns result in a pretty printed string format +// Eval evaluates JS function and returns result in a pretty printed string format. func (self *JSRE) Eval(code string) (s string, err error) { var val otto.Value val, err = self.Run(code) @@ -336,12 +269,16 @@ func (self *JSRE) Eval(code string) (s string, err error) { return fmt.Sprintf("%v", val), nil } -// compiles and then runs a piece of JS code -func (self *JSRE) Compile(fn string, src interface{}) error { - script, err := self.vm.Compile(fn, src) +// Compile compiles and then runs a piece of JS code. +func (self *JSRE) Compile(filename string, src interface{}) (err error) { + self.do(func(vm *otto.Otto) { _, err = compileAndRun(vm, filename, src) }) + return err +} + +func compileAndRun(vm *otto.Otto, filename string, src interface{}) (otto.Value, error) { + script, err := vm.Compile(filename, src) if err != nil { - return err + return otto.Value{}, err } - self.run(script, true) - return nil + return vm.Run(script) } |