diff options
Diffstat (limited to 'Godeps/_workspace/src/github.com/obscuren/qml/bridge.go')
| -rw-r--r-- | Godeps/_workspace/src/github.com/obscuren/qml/bridge.go | 681 |
1 files changed, 0 insertions, 681 deletions
diff --git a/Godeps/_workspace/src/github.com/obscuren/qml/bridge.go b/Godeps/_workspace/src/github.com/obscuren/qml/bridge.go deleted file mode 100644 index 77b36a566..000000000 --- a/Godeps/_workspace/src/github.com/obscuren/qml/bridge.go +++ /dev/null @@ -1,681 +0,0 @@ -package qml - -// #cgo CPPFLAGS: -I./cpp -// #cgo CXXFLAGS: -std=c++0x -pedantic-errors -Wall -fno-strict-aliasing -// #cgo LDFLAGS: -lstdc++ -// #cgo pkg-config: Qt5Core Qt5Widgets Qt5Quick -// -// #include <stdlib.h> -// -// #include "cpp/capi.h" -// -import "C" - -import ( - "fmt" - "os" - "reflect" - "runtime" - "sync/atomic" - "unsafe" - - "gopkg.in/qml.v1/cdata" -) - -var ( - guiFunc = make(chan func()) - guiDone = make(chan struct{}) - guiLock = 0 - guiMainRef uintptr - guiPaintRef uintptr - guiIdleRun int32 - - initialized int32 -) - -func init() { - runtime.LockOSThread() - guiMainRef = cdata.Ref() -} - -// Run runs the main QML event loop, runs f, and then terminates the -// event loop once f returns. -// -// Most functions from the qml package block until Run is called. -// -// The Run function must necessarily be called from the same goroutine as -// the main function or the application may fail when running on Mac OS. -func Run(f func() error) error { - if cdata.Ref() != guiMainRef { - panic("Run must be called on the initial goroutine so apps are portable to Mac OS") - } - if !atomic.CompareAndSwapInt32(&initialized, 0, 1) { - panic("qml.Run called more than once") - } - C.newGuiApplication() - C.idleTimerInit((*C.int32_t)(&guiIdleRun)) - done := make(chan error, 1) - go func() { - RunMain(func() {}) // Block until the event loop is running. - done <- f() - C.applicationExit() - }() - C.applicationExec() - return <-done -} - -// RunMain runs f in the main QML thread and waits for f to return. -// -// This is meant to be used by extensions that integrate directly with the -// underlying QML logic. -func RunMain(f func()) { - ref := cdata.Ref() - if ref == guiMainRef || ref == atomic.LoadUintptr(&guiPaintRef) { - // Already within the GUI or render threads. Attempting to wait would deadlock. - f() - return - } - - // Tell Qt we're waiting for the idle hook to be called. - if atomic.AddInt32(&guiIdleRun, 1) == 1 { - C.idleTimerStart() - } - - // Send f to be executed by the idle hook in the main GUI thread. - guiFunc <- f - - // Wait until f is done executing. - <-guiDone -} - -// Lock freezes all QML activity by blocking the main event loop. -// Locking is necessary before updating shared data structures -// without race conditions. -// -// It's safe to use qml functionality while holding a lock, as -// long as the requests made do not depend on follow up QML -// events to be processed before returning. If that happens, the -// problem will be observed as the application freezing. -// -// The Lock function is reentrant. That means it may be called -// multiple times, and QML activities will only be resumed after -// Unlock is called a matching number of times. -func Lock() { - // TODO Better testing for this. - RunMain(func() { - guiLock++ - }) -} - -// Unlock releases the QML event loop. See Lock for details. -func Unlock() { - RunMain(func() { - if guiLock == 0 { - panic("qml.Unlock called without lock being held") - } - guiLock-- - }) -} - -// Flush synchronously flushes all pending QML activities. -func Flush() { - // TODO Better testing for this. - RunMain(func() { - C.applicationFlushAll() - }) -} - -// Changed notifies all QML bindings that the given field value has changed. -// -// For example: -// -// qml.Changed(&value, &value.Field) -// -func Changed(value, fieldAddr interface{}) { - valuev := reflect.ValueOf(value) - fieldv := reflect.ValueOf(fieldAddr) - for valuev.Kind() == reflect.Ptr { - valuev = valuev.Elem() - } - if fieldv.Kind() != reflect.Ptr { - panic("qml.Changed received non-address value as fieldAddr") - } - fieldv = fieldv.Elem() - if fieldv.Type().Size() == 0 { - panic("cannot report changes on zero-sized fields") - } - offset := fieldv.UnsafeAddr() - valuev.UnsafeAddr() - if !(0 <= offset && offset < valuev.Type().Size()) { - panic("provided field is not a member of the given value") - } - - RunMain(func() { - tinfo := typeInfo(value) - for _, engine := range engines { - fold := engine.values[value] - for fold != nil { - C.goValueActivate(fold.cvalue, tinfo, C.int(offset)) - fold = fold.next - } - // TODO typeNew might also be a linked list keyed by the gvalue. - // This would prevent the iteration and the deferrals. - for fold, _ = range typeNew { - if fold.gvalue == value { - // Activate these later so they don't get recursively moved - // out of typeNew while the iteration is still happening. - defer C.goValueActivate(fold.cvalue, tinfo, C.int(offset)) - } - } - } - }) -} - -// hookIdleTimer is run once per iteration of the Qt event loop, -// within the main GUI thread, but only if at least one goroutine -// has atomically incremented guiIdleRun. -// -//export hookIdleTimer -func hookIdleTimer() { - var f func() - for { - select { - case f = <-guiFunc: - default: - if guiLock > 0 { - f = <-guiFunc - } else { - return - } - } - f() - guiDone <- struct{}{} - atomic.AddInt32(&guiIdleRun, -1) - } -} - -type valueFold struct { - engine *Engine - gvalue interface{} - cvalue unsafe.Pointer - init reflect.Value - prev *valueFold - next *valueFold - owner valueOwner -} - -type valueOwner uint8 - -const ( - cppOwner = 1 << iota - jsOwner -) - -// wrapGoValue creates a new GoValue object in C++ land wrapping -// the Go value contained in the given interface. -// -// This must be run from the main GUI thread. -func wrapGoValue(engine *Engine, gvalue interface{}, owner valueOwner) (cvalue unsafe.Pointer) { - gvaluev := reflect.ValueOf(gvalue) - gvaluek := gvaluev.Kind() - if gvaluek == reflect.Struct && !hashable(gvalue) { - name := gvaluev.Type().Name() - if name != "" { - name = " (" + name + ")" - } - panic("cannot hand an unhashable struct value" + name + " to QML logic; use its address instead") - } - if gvaluek == reflect.Ptr && gvaluev.Elem().Kind() == reflect.Ptr { - panic("cannot hand pointer of pointer to QML logic; use a simple pointer instead") - } - - painting := cdata.Ref() == atomic.LoadUintptr(&guiPaintRef) - - // Cannot reuse a jsOwner because the QML runtime may choose to destroy - // the value _after_ we hand it a new reference to the same value. - // See issue #68 for details. - prev, ok := engine.values[gvalue] - if ok && (prev.owner == cppOwner || painting) { - return prev.cvalue - } - - if painting { - panic("cannot allocate new objects while painting") - } - - parent := nilPtr - if owner == cppOwner { - parent = engine.addr - } - fold := &valueFold{ - engine: engine, - gvalue: gvalue, - owner: owner, - } - fold.cvalue = C.newGoValue(unsafe.Pointer(fold), typeInfo(gvalue), parent) - if prev != nil { - // Put new fold first so the single cppOwner, if any, is always the first entry. - fold.next = prev - prev.prev = fold - } - engine.values[gvalue] = fold - - //fmt.Printf("[DEBUG] value alive (wrapped): cvalue=%x gvalue=%x/%#v\n", fold.cvalue, addrOf(fold.gvalue), fold.gvalue) - stats.valuesAlive(+1) - C.engineSetContextForObject(engine.addr, fold.cvalue) - switch owner { - case cppOwner: - C.engineSetOwnershipCPP(engine.addr, fold.cvalue) - case jsOwner: - C.engineSetOwnershipJS(engine.addr, fold.cvalue) - } - return fold.cvalue -} - -func addrOf(gvalue interface{}) uintptr { - return reflect.ValueOf(gvalue).Pointer() -} - -// typeNew holds fold values that are created by registered types. -// These values are special in two senses: first, they don't have a -// reference to an engine before they are used in a context that can -// set the reference; second, these values always hold a new cvalue, -// because they are created as a side-effect of the registered type -// being instantiated (it's too late to reuse an existent cvalue). -// -// For these reasons, typeNew holds the fold for these values until -// their engine is known, and once it's known they may have to be -// added to the linked list, since mulitple references for the same -// gvalue may occur. -var typeNew = make(map[*valueFold]bool) - -//export hookGoValueTypeNew -func hookGoValueTypeNew(cvalue unsafe.Pointer, specp unsafe.Pointer) (foldp unsafe.Pointer) { - // Initialization is postponed until the engine is available, so that - // we can hand Init the qml.Object that represents the object. - init := reflect.ValueOf((*TypeSpec)(specp).Init) - fold := &valueFold{ - init: init, - gvalue: reflect.New(init.Type().In(0).Elem()).Interface(), - cvalue: cvalue, - owner: jsOwner, - } - typeNew[fold] = true - //fmt.Printf("[DEBUG] value alive (type-created): cvalue=%x gvalue=%x/%#v\n", fold.cvalue, addrOf(fold.gvalue), fold.gvalue) - stats.valuesAlive(+1) - return unsafe.Pointer(fold) -} - -//export hookGoValueDestroyed -func hookGoValueDestroyed(enginep unsafe.Pointer, foldp unsafe.Pointer) { - fold := (*valueFold)(foldp) - engine := fold.engine - if engine == nil { - before := len(typeNew) - delete(typeNew, fold) - if len(typeNew) == before { - panic("destroying value without an associated engine; who created the value?") - } - } else if engines[engine.addr] == nil { - // Must never do that. The engine holds memory references that C++ depends on. - panic(fmt.Sprintf("engine %p was released from global list while its values were still alive", engine.addr)) - } else { - switch { - case fold.prev != nil: - fold.prev.next = fold.next - if fold.next != nil { - fold.next.prev = fold.prev - } - case fold.next != nil: - fold.next.prev = fold.prev - if fold.prev != nil { - fold.prev.next = fold.next - } else { - fold.engine.values[fold.gvalue] = fold.next - } - default: - before := len(engine.values) - delete(engine.values, fold.gvalue) - if len(engine.values) == before { - panic("destroying value that knows about the engine, but the engine doesn't know about the value; who cleared the engine?") - } - if engine.destroyed && len(engine.values) == 0 { - delete(engines, engine.addr) - } - } - } - //fmt.Printf("[DEBUG] value destroyed: cvalue=%x gvalue=%x/%#v\n", fold.cvalue, addrOf(fold.gvalue), fold.gvalue) - stats.valuesAlive(-1) -} - -func deref(value reflect.Value) reflect.Value { - for { - switch value.Kind() { - case reflect.Ptr, reflect.Interface: - value = value.Elem() - continue - } - return value - } - panic("cannot happen") -} - -//export hookGoValueReadField -func hookGoValueReadField(enginep, foldp unsafe.Pointer, reflectIndex, getIndex, setIndex C.int, resultdv *C.DataValue) { - fold := ensureEngine(enginep, foldp) - - var field reflect.Value - if getIndex >= 0 { - field = reflect.ValueOf(fold.gvalue).Method(int(getIndex)).Call(nil)[0] - } else { - field = deref(reflect.ValueOf(fold.gvalue)).Field(int(reflectIndex)) - } - field = deref(field) - - // Cannot compare Type directly as field may be invalid (nil). - if field.Kind() == reflect.Slice && field.Type() == typeObjSlice { - // TODO Handle getters that return []qml.Object. - // TODO Handle other GoValue slices (!= []qml.Object). - resultdv.dataType = C.DTListProperty - *(*unsafe.Pointer)(unsafe.Pointer(&resultdv.data)) = C.newListProperty(foldp, C.intptr_t(reflectIndex), C.intptr_t(setIndex)) - return - } - - fieldk := field.Kind() - if fieldk == reflect.Slice || fieldk == reflect.Struct && field.Type() != typeRGBA { - if field.CanAddr() { - field = field.Addr() - } else if !hashable(field.Interface()) { - t := reflect.ValueOf(fold.gvalue).Type() - for t.Kind() == reflect.Ptr { - t = t.Elem() - } - panic(fmt.Sprintf("cannot access unaddressable and unhashable struct value on interface field %s.%s; value: %#v", t.Name(), t.Field(int(reflectIndex)).Name, field.Interface())) - } - } - var gvalue interface{} - if field.IsValid() { - gvalue = field.Interface() - } - - // TODO Strings are being passed in an unsafe manner here. There is a - // small chance that the field is changed and the garbage collector is run - // before C++ has a chance to look at the data. We can solve this problem - // by queuing up values in a stack, and cleaning the stack when the - // idle timer fires next. - packDataValue(gvalue, resultdv, fold.engine, jsOwner) -} - -//export hookGoValueWriteField -func hookGoValueWriteField(enginep, foldp unsafe.Pointer, reflectIndex, setIndex C.int, assigndv *C.DataValue) { - fold := ensureEngine(enginep, foldp) - v := reflect.ValueOf(fold.gvalue) - ve := v - for ve.Type().Kind() == reflect.Ptr { - ve = ve.Elem() - } - var field, setMethod reflect.Value - if reflectIndex >= 0 { - // It's a real field rather than a getter. - field = ve.Field(int(reflectIndex)) - } - if setIndex >= 0 { - // It has a setter. - setMethod = v.Method(int(setIndex)) - } - - assign := unpackDataValue(assigndv, fold.engine) - - // TODO Return false to the call site if it fails. That's how Qt seems to handle it internally. - err := convertAndSet(field, reflect.ValueOf(assign), setMethod) - if err != nil { - panic(err.Error()) - } -} - -func convertAndSet(to, from reflect.Value, setMethod reflect.Value) (err error) { - var toType reflect.Type - if setMethod.IsValid() { - toType = setMethod.Type().In(0) - } else { - toType = to.Type() - } - fromType := from.Type() - defer func() { - // TODO This is catching more than it should. There are calls - // to custom code below that should be isolated. - if v := recover(); v != nil { - err = fmt.Errorf("cannot use %s as a %s", fromType, toType) - } - }() - if fromType == typeList && toType.Kind() == reflect.Slice { - list := from.Interface().(*List) - from = reflect.MakeSlice(toType, len(list.data), len(list.data)) - elemType := toType.Elem() - for i, elem := range list.data { - from.Index(i).Set(reflect.ValueOf(elem).Convert(elemType)) - } - } else if fromType == typeMap && toType.Kind() == reflect.Map { - qmap := from.Interface().(*Map) - from = reflect.MakeMap(toType) - elemType := toType.Elem() - for i := 0; i < len(qmap.data); i += 2 { - key := reflect.ValueOf(qmap.data[i]) - val := reflect.ValueOf(qmap.data[i+1]) - if val.Type() != elemType { - val = val.Convert(elemType) - } - from.SetMapIndex(key, val) - } - } else if toType != fromType { - from = from.Convert(toType) - } - if setMethod.IsValid() { - setMethod.Call([]reflect.Value{from}) - } else { - to.Set(from) - } - return nil -} - -var ( - dataValueSize = uintptr(unsafe.Sizeof(C.DataValue{})) - dataValueArray [C.MaxParams]C.DataValue -) - -//export hookGoValueCallMethod -func hookGoValueCallMethod(enginep, foldp unsafe.Pointer, reflectIndex C.int, args *C.DataValue) { - fold := ensureEngine(enginep, foldp) - v := reflect.ValueOf(fold.gvalue) - - // TODO Must assert that v is necessarily a pointer here, but we shouldn't have to manipulate - // gvalue here for that. This should happen in a sensible place in the wrapping functions - // that can still error out to the user in due time. - - method := v.Method(int(reflectIndex)) - methodt := method.Type() - methodName := v.Type().Method(int(reflectIndex)).Name - - // TODO Ensure methods with more parameters than this are not registered. - var params [C.MaxParams]reflect.Value - var err error - - numIn := methodt.NumIn() - for i := 0; i < numIn; i++ { - paramdv := (*C.DataValue)(unsafe.Pointer(uintptr(unsafe.Pointer(args)) + (uintptr(i)+1)*dataValueSize)) - param := reflect.ValueOf(unpackDataValue(paramdv, fold.engine)) - if argt := methodt.In(i); param.Type() != argt { - param, err = convertParam(methodName, i, param, argt) - if err != nil { - panic(err.Error()) - } - } - params[i] = param - } - - result := method.Call(params[:numIn]) - - if len(result) == 1 { - packDataValue(result[0].Interface(), args, fold.engine, jsOwner) - } else if len(result) > 1 { - if len(result) > len(dataValueArray) { - panic("function has too many results") - } - for i, v := range result { - packDataValue(v.Interface(), &dataValueArray[i], fold.engine, jsOwner) - } - args.dataType = C.DTVariantList - *(*unsafe.Pointer)(unsafe.Pointer(&args.data)) = C.newVariantList(&dataValueArray[0], C.int(len(result))) - } -} - -func convertParam(methodName string, index int, param reflect.Value, argt reflect.Type) (reflect.Value, error) { - out := reflect.New(argt).Elem() - err := convertAndSet(out, param, reflect.Value{}) - if err != nil { - err = fmt.Errorf("cannot convert parameter %d of method %s from %s to %s; provided value: %#v", - index, methodName, param.Type(), argt, param.Interface()) - return reflect.Value{}, err - } - return out, nil -} - -func printPaintPanic() { - if v := recover(); v != nil { - buf := make([]byte, 8192) - runtime.Stack(buf, false) - fmt.Fprintf(os.Stderr, "panic while painting: %s\n\n%s", v, buf) - } -} - -//export hookGoValuePaint -func hookGoValuePaint(enginep, foldp unsafe.Pointer, reflectIndex C.intptr_t) { - // Besides a convenience this is a workaround for http://golang.org/issue/8588 - defer printPaintPanic() - defer atomic.StoreUintptr(&guiPaintRef, 0) - - // The main GUI thread is mutex-locked while paint methods are called, - // so no two paintings should be happening at the same time. - atomic.StoreUintptr(&guiPaintRef, cdata.Ref()) - - fold := ensureEngine(enginep, foldp) - if fold.init.IsValid() { - return - } - - painter := &Painter{engine: fold.engine, obj: &Common{fold.cvalue, fold.engine}} - v := reflect.ValueOf(fold.gvalue) - method := v.Method(int(reflectIndex)) - method.Call([]reflect.Value{reflect.ValueOf(painter)}) -} - -func ensureEngine(enginep, foldp unsafe.Pointer) *valueFold { - fold := (*valueFold)(foldp) - if fold.engine != nil { - if fold.init.IsValid() { - initGoType(fold) - } - return fold - } - - if enginep == nilPtr { - panic("accessing value without an engine pointer; who created the value?") - } - engine := engines[enginep] - if engine == nil { - panic("unknown engine pointer; who created the engine?") - } - fold.engine = engine - prev := engine.values[fold.gvalue] - if prev != nil { - for prev.next != nil { - prev = prev.next - } - prev.next = fold - fold.prev = prev - } else { - engine.values[fold.gvalue] = fold - } - before := len(typeNew) - delete(typeNew, fold) - if len(typeNew) == before { - panic("value had no engine, but was not created by a registered type; who created the value?") - } - initGoType(fold) - return fold -} - -func initGoType(fold *valueFold) { - if cdata.Ref() == atomic.LoadUintptr(&guiPaintRef) { - go RunMain(func() { _initGoType(fold, true) }) - } else { - _initGoType(fold, false) - } -} - -func _initGoType(fold *valueFold, schedulePaint bool) { - if !fold.init.IsValid() { - return - } - // TODO Would be good to preserve identity on the Go side. See unpackDataValue as well. - obj := &Common{engine: fold.engine, addr: fold.cvalue} - fold.init.Call([]reflect.Value{reflect.ValueOf(fold.gvalue), reflect.ValueOf(obj)}) - fold.init = reflect.Value{} - if schedulePaint { - obj.Call("update") - } -} - -//export hookPanic -func hookPanic(message *C.char) { - defer C.free(unsafe.Pointer(message)) - panic(C.GoString(message)) -} - -func listSlice(fold *valueFold, reflectIndex C.intptr_t) *[]Object { - field := deref(reflect.ValueOf(fold.gvalue)).Field(int(reflectIndex)) - return field.Addr().Interface().(*[]Object) -} - -//export hookListPropertyAt -func hookListPropertyAt(foldp unsafe.Pointer, reflectIndex, setIndex C.intptr_t, index C.int) (objp unsafe.Pointer) { - fold := (*valueFold)(foldp) - slice := listSlice(fold, reflectIndex) - return (*slice)[int(index)].Common().addr -} - -//export hookListPropertyCount -func hookListPropertyCount(foldp unsafe.Pointer, reflectIndex, setIndex C.intptr_t) C.int { - fold := (*valueFold)(foldp) - slice := listSlice(fold, reflectIndex) - return C.int(len(*slice)) -} - -//export hookListPropertyAppend -func hookListPropertyAppend(foldp unsafe.Pointer, reflectIndex, setIndex C.intptr_t, objp unsafe.Pointer) { - fold := (*valueFold)(foldp) - slice := listSlice(fold, reflectIndex) - var objdv C.DataValue - objdv.dataType = C.DTObject - *(*unsafe.Pointer)(unsafe.Pointer(&objdv.data)) = objp - newslice := append(*slice, unpackDataValue(&objdv, fold.engine).(Object)) - if setIndex >= 0 { - reflect.ValueOf(fold.gvalue).Method(int(setIndex)).Call([]reflect.Value{reflect.ValueOf(newslice)}) - } else { - *slice = newslice - } -} - -//export hookListPropertyClear -func hookListPropertyClear(foldp unsafe.Pointer, reflectIndex, setIndex C.intptr_t) { - fold := (*valueFold)(foldp) - slice := listSlice(fold, reflectIndex) - newslice := (*slice)[0:0] - if setIndex >= 0 { - reflect.ValueOf(fold.gvalue).Method(int(setIndex)).Call([]reflect.Value{reflect.ValueOf(newslice)}) - } else { - for i := range *slice { - (*slice)[i] = nil - } - *slice = newslice - } -} |