Golang C.g_error_free函数代码示例

func goError(err *C.GError) error {
	if err != nil {
		defer C.g_error_free(err)
		return errors.New(C.GoString((*C.char)(err.message)))
	}
	return nil
}

// RunJavaScript runs script asynchronously in the context of the current page
// in the WebView. Upon completion, resultCallback will be called with the
// result of evaluating the script, or with an error encountered during
// execution. To get the stack trace and other error logs, use the
// ::console-message signal.
//
// See also: webkit_web_view_run_javascript at
// http://webkitgtk.org/reference/webkit2gtk/stable/WebKitWebView.html#webkit-web-view-run-javascript
func (v *WebView) RunJavaScript(script string, resultCallback func(result *gojs.Value, err error)) {
	var cCallback C.GAsyncReadyCallback
	var userData C.gpointer
	var err error
	if resultCallback != nil {
		callback := func(result *C.GAsyncResult) {
			var jserr *C.GError
			jsResult := C.webkit_web_view_run_javascript_finish(v.webView, result, &jserr)
			if jsResult == nil {
				defer C.g_error_free(jserr)
				msg := C.GoString((*C.char)(jserr.message))
				resultCallback(nil, errors.New(msg))
				return
			}
			ctxRaw := gojs.RawGlobalContext(unsafe.Pointer(C.webkit_javascript_result_get_global_context(jsResult)))
			jsValRaw := gojs.RawValue(unsafe.Pointer(C.webkit_javascript_result_get_value(jsResult)))
			ctx := (*gojs.Context)(gojs.NewGlobalContextFrom(ctxRaw))
			jsVal := ctx.NewValueFrom(jsValRaw)
			resultCallback(jsVal, nil)
		}
		cCallback, userData, err = newGAsyncReadyCallback(callback)
		if err != nil {
			panic(err)
		}
	}
	cScript := C.CString(script)
	defer C.free(unsafe.Pointer(cScript))
	C.webkit_web_view_run_javascript(v.webView, (*C.gchar)(cScript), nil, cCallback, userData)
}

// Close is a wrapper around gdk_pixbuf_loader_close().  An error is
// returned instead of a bool like the native C function to support the
// io.Closer interface.
func (v *PixbufLoader) Close() error {
	var err *C.GError

	if ok := gobool(C.gdk_pixbuf_loader_close(v.native(), &err)); !ok {
		defer C.g_error_free(err)
		return errors.New(C.GoString((*C.char)(err.message)))
	}
	return nil
}

// ParseWarning() is a wrapper around gst_message_parse_warning().
func (v *Message) ParseWarning() (err error, debug string) {
	var e *C.GError
	var d *C.gchar
	C.gst_message_parse_warning(v.native(), &e, &d)
	eMessage := C.GoString((*C.char)(e.message))
	defer C.g_error_free(e)
	debug = C.GoString((*C.char)(d))
	defer C.g_free((C.gpointer)(d))
	return errors.New(eMessage), debug
}

// SetIconFromFile is a wrapper around gtk_window_set_icon_from_file().
func (v *Window) SetIconFromFile(file string) error {
	cstr := C.CString(file)
	defer C.free(unsafe.Pointer(cstr))
	var err *C.GError = nil
	res := C.gtk_window_set_icon_from_file(v.native(), (*C.gchar)(cstr), &err)
	if res == 0 {
		defer C.g_error_free(err)
		return errors.New(C.GoString((*C.char)(err.message)))
	}
	return nil
}

func PixbufSaveToStreamFinish(async_result *C.GAsyncResult) (_go__return__ bool, _error_ error) {
	var _cgo_error_ *C.GError
	var _return_ C.gboolean
	_return_ = C._gdk_pixbuf_save_to_stream_finish(async_result, unsafe.Pointer(&_cgo_error_))
	if _cgo_error_ != nil {
		_error_ = &Error{C.GoString((*C.char)(unsafe.Pointer(_cgo_error_.message)))}
		defer C.g_error_free(_cgo_error_)
	}
	_go__return__ = _return_ == (C.gboolean)(C.TRUE)
	return
}

func PixbufNewFromStream(stream *C.GInputStream, cancellable *C.GCancellable) (_go__return__ Pixbuf, _error_ error) {
	var _cgo_error_ *C.GError
	var _return_ *C.GdkPixbuf
	_return_ = C._gdk_pixbuf_new_from_stream(stream, cancellable, unsafe.Pointer(&_cgo_error_))
	if _cgo_error_ != nil {
		_error_ = &Error{C.GoString((*C.char)(unsafe.Pointer(_cgo_error_.message)))}
		defer C.g_error_free(_cgo_error_)
	}
	_go__return__ = ToPixbuf(unsafe.Pointer(_return_))
	return
}

func (_self_ *PixbufLoader) Close() (_go__return__ bool, _error_ error) {
	var _cgo_error_ *C.GError
	var _return_ C.gboolean
	_return_ = C._gdk_pixbuf_loader_close((*C.GdkPixbufLoader)(_self_._value_), unsafe.Pointer(&_cgo_error_))
	if _cgo_error_ != nil {
		_error_ = &Error{C.GoString((*C.char)(unsafe.Pointer(_cgo_error_.message)))}
		defer C.g_error_free(_cgo_error_)
	}
	_go__return__ = _return_ == (C.gboolean)(C.TRUE)
	return
}

func PixbufNewFromStreamFinish(async_result *C.GAsyncResult) (_go__return__ Pixbuf, _error_ error) {
	var _cgo_error_ *C.GError
	var _return_ *C.GdkPixbuf
	_return_ = C._gdk_pixbuf_new_from_stream_finish(async_result, unsafe.Pointer(&_cgo_error_))
	if _cgo_error_ != nil {
		_error_ = &Error{C.GoString((*C.char)(unsafe.Pointer(_cgo_error_.message)))}
		defer C.g_error_free(_cgo_error_)
	}
	_go__return__ = ToPixbuf(unsafe.Pointer(_return_))
	return
}

func NewElementFromUri(t C.GstURIType, uri, name string) (*C.GstElement, error) {
	var err *C.GError
	element := C.gst_element_make_from_uri(t, toGStr(uri), toGStr(name), &err)
	if element == nil {
		defer C.g_error_free(err)
		return nil, errors.New(fmt.Sprintf("%s", err.message))
	}
	runtime.SetFinalizer(element, func(e *C.GstElement) {
		C.gst_object_unref(asGPtr(element))
	})
	return element, nil
}

// GetSnapshotCustom runs asynchronously, taking a snapshot of the WebView.
// Upon completion, resultCallback will be called with a copy of the underlying
// bitmap backing store for the frame, or with an error encountered during
// execution.
//
// See also: webkit_web_view_get_snapshot at
// http://webkitgtk.org/reference/webkit2gtk/stable/WebKitWebView.html#webkit-web-view-get-snapshot
func (v *WebView) GetSnapshotCustom(region SnapshotRegion, options SnapshotOptions, resultCallback func(result *image.RGBA, err error)) {
	var cCallback C.GAsyncReadyCallback
	var userData C.gpointer
	var err error
	if resultCallback != nil {
		callback := func(result *C.GAsyncResult) {
			var snapErr *C.GError
			snapResult := C.webkit_web_view_get_snapshot_finish(v.webView, result, &snapErr)
			if snapResult == nil {
				defer C.g_error_free(snapErr)
				msg := C.GoString((*C.char)(snapErr.message))
				resultCallback(nil, errors.New(msg))
				return
			}
			defer C.cairo_surface_destroy(snapResult)

			if C.cairo_surface_get_type(snapResult) != cairoSurfaceTypeImage ||
				C.cairo_image_surface_get_format(snapResult) != cairoImageSurfaceFormatARGB32 {
				panic("Snapshot in unexpected format")
			}

			w := int(C.cairo_image_surface_get_width(snapResult))
			h := int(C.cairo_image_surface_get_height(snapResult))
			stride := int(C.cairo_image_surface_get_stride(snapResult))
			C.cairo_surface_flush(snapResult)
			data := unsafe.Pointer(C.cairo_image_surface_get_data(snapResult))

			//(miha) fix endianes depended byte order, and copy to go slice at the same time.
			data_fixed := make([]byte, stride*h)
			C.gowk2_cairo_endian_depended_ARGB32_to_RGBA((*C.uchar)(data), (*C.uchar)(&data_fixed[0]), C.uint(stride*h))
			rgba := &image.RGBA{data_fixed, stride, image.Rect(0, 0, w, h)}

			// slower but doesn't use Go pointers inside C. See https://github.com/golang/go/issues/8310 !!!!!!!
			//C.gowk2_cairo_endian_depended_ARGB32_to_RGBA((*C.uchar)(data), C.uint(stride*h))
			//rgba := &image.RGBA{C.GoBytes(data, C.int(stride*h)), stride, image.Rect(0, 0, w, h)}

			resultCallback(rgba, nil)
		}
		cCallback, userData, err = newGAsyncReadyCallback(callback)
		if err != nil {
			panic(err)
		}
	}

	C.webkit_web_view_get_snapshot(v.webView,
		(C.WebKitSnapshotRegion)(region),
		(C.WebKitSnapshotOptions)(options),
		nil,
		cCallback,
		userData)
}

// SavePNG is a wrapper around gdk_pixbuf_save().
// Compression is a number between 0...9
func (v *Pixbuf) SavePNG(path string, compression int) error {
	cpath := C.CString(path)
	ccompression := C.CString(strconv.Itoa(compression))
	defer C.free(unsafe.Pointer(cpath))
	defer C.free(unsafe.Pointer(ccompression))

	var err *C.GError
	c := C._gdk_pixbuf_save_png(v.native(), cpath, &err, ccompression)
	if !gobool(c) {
		defer C.g_error_free(err)
		return errors.New(C.GoString((*C.char)(err.message)))
	}
	return nil
}

// SaveJPEG is a wrapper around gdk_pixbuf_save().
// Quality is a number between 0...100
func (v *Pixbuf) SaveJPEG(path string, quality int) error {
	cpath := C.CString(path)
	cquality := C.CString(strconv.Itoa(quality))
	defer C.free(unsafe.Pointer(cpath))
	defer C.free(unsafe.Pointer(cquality))

	var err *C.GError
	c := C._gdk_pixbuf_save_jpeg(v.native(), cpath, &err, cquality)
	if !gobool(c) {
		defer C.g_error_free(err)
		return errors.New(C.GoString((*C.char)(err.message)))
	}
	return nil
}

// PixbufNewFromFileAtScale() is a wrapper around gdk_pixbuf_new_from_file_at_scale().
func PixbufNewFromFileAtScale(fileName string, width, height int, preserveAspectRatio bool) (*Pixbuf, error) {
	var cerr *C.GError
	cstr := C.CString(fileName)
	defer C.free(unsafe.Pointer(cstr))
	c := C.gdk_pixbuf_new_from_file_at_scale(cstr, C.int(width), C.int(height), gbool(preserveAspectRatio), &cerr)
	if c == nil {
		defer C.g_error_free(cerr)
		return nil, errors.New(C.GoString((*C.char)(C.error_get_message(cerr))))
	}
	obj := &glib.Object{glib.ToGObject(unsafe.Pointer(c))}
	p := wrapPixbuf(obj)
	runtime.SetFinalizer(obj, (*glib.Object).Unref)
	return p, nil
}

// PixbufNewFromFile() is a wrapper around gdk_pixbuf_new_from_file().
func PixbufNewFromFile(fileName string) (*Pixbuf, error) {
	var cerr *C.GError
	cstr := C.CString(fileName)
	defer C.free(unsafe.Pointer(cstr))
	c := C.gdk_pixbuf_new_from_file(cstr, &cerr)
	if c == nil {
		defer C.g_error_free(cerr)
		return nil, errors.New(C.GoString((*C.char)(C.error_get_message(cerr))))
	}
	obj := &glib.Object{glib.ToGObject(unsafe.Pointer(c))}
	p := wrapPixbuf(obj)
	runtime.SetFinalizer(obj, (*glib.Object).Unref)
	return p, nil
}