From 80ed90f6737c96de6e9392026d3a94f385192eed Mon Sep 17 00:00:00 2001 From: Sasha Koshka Date: Tue, 6 Jun 2023 13:41:30 -0400 Subject: [PATCH] Initial commit --- LICENSE | 674 +++++++++++++++++++++++++++++++++++++++++++++++++++ README.md | 3 + claim.go | 169 +++++++++++++ data.go | 78 ++++++ doc.go | 3 + go.mod | 8 + go.sum | 6 + selection.go | 282 +++++++++++++++++++++ 8 files changed, 1223 insertions(+) create mode 100644 LICENSE create mode 100644 README.md create mode 100644 claim.go create mode 100644 data.go create mode 100644 doc.go create mode 100644 go.mod create mode 100644 go.sum create mode 100644 selection.go diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..f288702 --- /dev/null +++ b/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/README.md b/README.md new file mode 100644 index 0000000..981589c --- /dev/null +++ b/README.md @@ -0,0 +1,3 @@ +# xgbsel + +Easy clipboard/selection manipulation and access with xgb and xgbutil. diff --git a/claim.go b/claim.go new file mode 100644 index 0000000..0b82124 --- /dev/null +++ b/claim.go @@ -0,0 +1,169 @@ +package xgbsel + +import "io" +import "github.com/jezek/xgb" +import "github.com/jezek/xgbutil" +import "github.com/jezek/xgb/xproto" +import "github.com/jezek/xgbutil/xprop" +import "github.com/jezek/xgbutil/xevent" +import "github.com/jezek/xgbutil/xwindow" + +// Claim represents a claim that a window has on a particular selection. +type Claim struct { + window *xwindow.Window + data Data + selection xproto.Atom +} + +// NewClaim claims ownership of a specified selection, and allows using data +// passed to it to fulfill requests for the selection's contents. +func NewClaim (window *xwindow.Window, selection xproto.Atom, data Data) *Claim { + // Follow: + // https://tronche.com/gui/x/icccm/sec-2.html#s-2.1 + + // A client wishing to acquire ownership of a particular selection + // should call SetSelectionOwner. The client should set the specified + // selection to the atom that represents the selection, set the + // specified owner to some window that the client created, and set the + // specified time to some time between the current last-change time of + // the selection concerned and the current server time. This time value + // usually will be obtained from the timestamp of the event that + // triggers the acquisition of the selection. Clients should not set the + // time value to CurrentTime, because if they do so, they have no way of + // finding when they gained ownership of the selection. Clients must use + // a window they created so that requestors can route events to the + // owner of the selection. + err := xproto.SetSelectionOwnerChecked ( + window.X.Conn(), + window.Id, selection, 0).Check() // FIXME: should not be zero + if err != nil { return nil } + + ownerReply, err := xproto.GetSelectionOwner ( + window.X.Conn(), selection).Reply() + if err != nil { return nil } + if ownerReply.Owner != window.Id { return nil } + + return &Claim { + window: window, + data: data, + selection: selection, + } +} + +func (claim *Claim) refuseSelectionRequest (request xevent.SelectionRequestEvent) { + // ... refuse the SelectionRequest by sending the requestor window a + // SelectionNotify event with the property set to None (by means of a + // SendEvent request with an empty event mask). + event := xproto.SelectionNotifyEvent { + Requestor: request.Requestor, + Selection: request.Selection, + Target: request.Target, + Property: 0, + }.Bytes() + xproto.SendEvent ( + claim.window.X.Conn(), + false, request.Requestor, 0, string(event)) +} + +func (claim *Claim) fulfillSelectionRequest ( + data []byte, + format byte, + ty xproto.Atom, + request xevent.SelectionRequestEvent, +) { + die := func () { claim.refuseSelectionRequest(request) } + + // If the specified property is not None, the owner should place the + // data resulting from converting the selection into the specified + // property on the requestor window and should set the property's type + // to some appropriate value, which need not be the same as the + // specified target. + err := xproto.ChangePropertyChecked ( + claim.window.X.Conn(), + xproto.PropModeReplace, request.Requestor, + request.Property, + ty, format, + uint32(len(data) / (int(format) / 8)), data).Check() + if err != nil { die() } + + // If the property is successfully stored, the owner should acknowledge + // the successful conversion by sending the requestor window a + // SelectionNotify event (by means of a SendEvent request with an empty + // mask). + event := xproto.SelectionNotifyEvent { + Requestor: request.Requestor, + Selection: request.Selection, + Target: request.Target, + Property: request.Property, + }.Bytes() + xproto.SendEvent ( + claim.window.X.Conn(), + false, request.Requestor, 0, string(event)) +} + +// While the selection claim is active, HandleSelectionRequest should be called +// when the owner window recieves a SelectionRequest event. +func (claim *Claim) HandleSelectionRequest ( + connection *xgbutil.XUtil, + event xevent.SelectionRequestEvent, +) { + // Follow: + // https://tronche.com/gui/x/icccm/sec-2.html#s-2.2 + + die := func () { claim.refuseSelectionRequest(event) } + + // When a requestor wants the value of a selection, the owner receives a + // SelectionRequest event. The specified owner and selection will be the + // values that were specified in the SetSelectionOwner request. The + // owner should compare the timestamp with the period it has owned the + // selection and, if the time is outside, refuse the SelectionRequest. + if event.Selection != claim.selection { die(); return } + + // If the specified property is None, the requestor is an obsolete + // client. Owners are encouraged to support these clients by using the + // specified target atom as the property name to be used for the reply. + if event.Property == 0 { + event.Property = event.Target + } + + // Otherwise, the owner should use the target to decide the form into + // which the selection should be converted. Some targets may be defined + // such that requestors can pass parameters along with the request. The + // owner will find these parameters in the property named in the + // selection request. The type, format, and contents of this property + // are dependent upon the definition of the target. If the target is not + // defined to have parameters, the owner should ignore the property if + // it is present. If the selection cannot be converted into a form based + // on the target (and parameters, if any), the owner should refuse the + // SelectionRequest as previously described. + targetName, err := xprop.AtomName(claim.window.X, event.Target) + if err != nil { die(); return } + + switch targetName { + case "TARGETS": + // generate a list of supported targets + targetNames := []Target { "TARGETS" } + targetNames = append(targetNames, claim.data.Supported()...) + data := make([]byte, len(targetNames) * 4) + for index, name := range targetNames { + atom, err := xprop.Atm(claim.window.X, string(name)) + if err != nil { die(); return } + xgb.Put32(data[(index) * 4:], uint32(atom)) + } + + // send that list to the requestor + atomAtom, err := xprop.Atm(claim.window.X, "ATOM") + if err != nil { die(); return } + claim.fulfillSelectionRequest(data, 32, atomAtom, event) + + default: + // respond with data + reader, ok := claim.data.Convert(Target(targetName)) + if !ok { die(); return } + reader.Seek(0, io.SeekStart) + data, err := io.ReadAll(reader) + reader.Close() + if err != nil { die() } + claim.fulfillSelectionRequest(data, 8, event.Target, event) + } +} diff --git a/data.go b/data.go new file mode 100644 index 0000000..f01993c --- /dev/null +++ b/data.go @@ -0,0 +1,78 @@ +package xgbsel + +import "io" +import "strings" + +// Data represents a polymorphic data structure +type Data interface { + Convert (Target) (reader io.ReadSeekCloser, ok bool) + Supported () []Target +} + +// Target represents an X selection target. It defines the type of data stored +// within an X selection. This data may be a mime type, or a more specific name +// that is unique to X. A list of these names can be found here: +// https://tronche.com/gui/x/icccm/sec-2.html#s-2.6.2 +type Target string + +type Confidence int; const ( + ConfidenceNone Confidence = iota + ConfidencePartial + ConfidenceFull +) + +// ToMime converts the specified target to a MIME type. Because a single MIME +// type may correspond to several targets, a confidence value is returned +// representing how good of a match it is. If data is represented by multiple +// targets, they can be checked one after the other and the one with the highest +// confidence value chosen. +func (target Target) ToMime () (string, Confidence) { + // TODO: add other stuff. reference this table: + // https://tronche.com/gui/x/icccm/sec-2.html#s-2.6.2 + // perhaps we should also have parameters for mime types so we can + // return an encoding here for things like STRING? + switch target { + case "ADOBE_PORTABLE_DOCUMENT_FORMAT": + return "application/pdf", ConfidenceFull + case "APPLE_PICT": + return "image/pict", ConfidenceFull + case + "POSTSCRIPT", + "ENCAPSULATED_POSTSCRIPT", + "ENCAPSULATED_POSTSCRIPT_INTERCHANGE": + return "application/postscript", ConfidenceFull + case "FILE_NAME": + return "text/uri-list", ConfidenceFull + case "UTF8_STRING": + return "text/plain", ConfidenceFull + case "TEXT": + return "text/plain", ConfidencePartial + case "STRING": + return "text/plain", ConfidencePartial + default: + if strings.Count(string(target), "/") == 1 { + return string(target), ConfidenceFull + } else { + return "", ConfidenceNone + } + } +} + +// MimeToTargets returns a list of targets that correspond to a specified MIME +// type. +func MimeToTargets (mime string) []Target { + targets := []Target { Target(mime) } + switch mime { + case "application/pdf": + targets = append(targets, "ADOBE_PORTABLE_DOCUMENT_FORMAT") + case "image/pict": + targets = append(targets, "APPLE_PICT") + case "application/postscript": + targets = append(targets, "POSTSCRIPT") + case "text/uri-list": + targets = append(targets, "FILE_NAME") + case "text/plain": + targets = append(targets, "UTF8_STRING", "TEXT", "STRING") + } + return targets +} diff --git a/doc.go b/doc.go new file mode 100644 index 0000000..bfa78e3 --- /dev/null +++ b/doc.go @@ -0,0 +1,3 @@ +// Package xgbsel provides easy clipboard/selection manipulation and access with +// xgb and xgbutil. +package xgbsel diff --git a/go.mod b/go.mod new file mode 100644 index 0000000..4551206 --- /dev/null +++ b/go.mod @@ -0,0 +1,8 @@ +module git.tebibyte.media/sashakoshka/xgbsel + +go 1.20 + +require ( + github.com/jezek/xgb v1.1.0 + github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 +) diff --git a/go.sum b/go.sum new file mode 100644 index 0000000..1ea7ee1 --- /dev/null +++ b/go.sum @@ -0,0 +1,6 @@ +github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298/go.mod h1:D+QujdIlUNfa0igpNMk6UIvlb6C252URs4yupRUV4lQ= +github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966/go.mod h1:Mid70uvE93zn9wgF92A/r5ixgnvX8Lh68fxp9KQBaI0= +github.com/jezek/xgb v1.1.0 h1:wnpxJzP1+rkbGclEkmwpVFQWpuE2PUGNUzP8SbfFobk= +github.com/jezek/xgb v1.1.0/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk= +github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 h1:Pf/0BAbppEOq4azPH6fnvUX2dycAwZdGkdxFn25j44c= +github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y= diff --git a/selection.go b/selection.go new file mode 100644 index 0000000..f51d863 --- /dev/null +++ b/selection.go @@ -0,0 +1,282 @@ +package xgbsel + +import "io" +import "bytes" +import "errors" +import "github.com/jezek/xgb" +import "github.com/jezek/xgbutil" +import "github.com/jezek/xgb/xproto" +import "github.com/jezek/xgbutil/xprop" +import "github.com/jezek/xgbutil/xevent" +import "github.com/jezek/xgbutil/xwindow" + +type selReqState int; const ( + selReqStateClosed selReqState = iota + selReqStateAwaitTargets + selReqStateAwaitValue + selReqStateAwaitChunk +) + +// Requestor provices details about the request such as the window that is +// requesting the selection data, and what targets it accepts. +type Requestor interface { + Window () *xwindow.Window + Choose (from []Target) (chosen Target, ok bool) + Success (Target, io.ReadCloser) + Failure (error) +} + +// Request represents an ongoing request for the selection contents. +type Request struct { + state selReqState + requestor Requestor + source xproto.Atom + destination xproto.Atom + incrBuffer []byte + incrTarget Target +} + +// NewRequest sends a new selection request. +func NewRequest (requestor Requestor, source, destination xproto.Atom) *Request { + request := &Request { + source: source, + destination: destination, + requestor: requestor, + } + + targets, err := xprop.Atm(requestor.Window().X, "TARGETS") + if err != nil { request.die(err); return nil } + request.convertSelection(targets, selReqStateAwaitTargets) + return request +} + +func (request *Request) convertSelection (target xproto.Atom, switchTo selReqState) { + // The requestor should set the property argument to the name of a + // property that the owner can use to report the value of the selection. + // Requestors should ensure that the named property does not exist on + // the window before issuing the ConvertSelection. The exception to this + // rule is when the requestor intends to pass parameters with the + // request. Some targets may be defined such that requestors can pass + // parameters along with the request. If the requestor wishes to provide + // parameters to a request, they should be placed in the specified + // property on the requestor window before the requestor issues the + // ConvertSelection request, and this property should be named in the + // request. + err := xproto.DeletePropertyChecked ( + request.requestor.Window().X.Conn(), + request.requestor.Window().Id, + request.destination).Check() + if err != nil { request.die(err); return } + + // The selection argument specifies the particular selection involved, + // and the target argument specifies the required form of the + // information. For information about the choice of suitable atoms to + // use, see section 2.6. The requestor should set the requestor argument + // to a window that it created; the owner will place the reply property + // there. The requestor should set the time argument to the timestamp on + // the event that triggered the request for the selection value. Note + // that clients should not specify CurrentTime*. + err = xproto.ConvertSelectionChecked ( + request.requestor.Window().X.Conn(), + request.requestor.Window().Id, + request.source, + target, + request.destination, + // TODO: *possibly replace this zero with an actual timestamp + // received from the server. this is non-trivial as we cannot + // rely on the timestamp of the last received event, because + // there is a possibility that this method is invoked + // asynchronously from within tomo.Do(). + 0).Check() + if err != nil { request.die(err); return } + + request.state = switchTo +} + +func (request *Request) die (err error) { + request.requestor.Failure(err) + request.state = selReqStateClosed +} + +func (request *Request) finalize (target Target, reader io.ReadCloser) { + request.requestor.Success(target, reader) + request.state = selReqStateClosed +} + +func (request *Request) open () bool { + return request.state != selReqStateClosed +} + +// While the selection request is active, HandleSelectionNotify should be called +// when the requesting window recieves a SelectionNotify event. +func (request *Request) HandleSelectionNotify ( + connection *xgbutil.XUtil, + event xevent.SelectionNotifyEvent, +) { + // the only valid states that we can process a SelectionNotify event in + invalidState := + request.state != selReqStateAwaitValue && + request.state != selReqStateAwaitTargets + if invalidState { return } + + // Follow: + // https://tronche.com/gui/x/icccm/sec-2.html#s-2.4 + + // If the property argument is None, the conversion has been refused. + // This can mean either that there is no owner for the selection, that + // the owner does not support the conversion implied by the target, or + // that the server did not have sufficient space to accommodate the + // data. + if event.Property == 0 { request.die(nil); return } + + // When using GetProperty to retrieve the value of a selection, the + // property argument should be set to the corresponding value in the + // SelectionNotify event. Because the requestor has no way of knowing + // beforehand what type the selection owner will use, the type argument + // should be set to AnyPropertyType. Several GetProperty requests may be + // needed to retrieve all the data in the selection; each should set the + // long-offset argument to the amount of data received so far, and the + // size argument to some reasonable buffer size (see section 2.5). If + // the returned value of bytes-after is zero, the whole property has + // been transferred. + reply, err := xproto.GetProperty ( + connection.Conn(), false, request.requestor.Window().Id, + event.Property, xproto.GetPropertyTypeAny, + 0, (1 << 32) - 1).Reply() + if err != nil { request.die(err); return } + if reply.Format == 0 { + request.die(errors.New("x: missing selection property")) + return + } + + // https://tronche.com/gui/x/icccm/sec-2.html#s-2.7.2 + // Requestors may receive a property of type INCR9 in response to any + // target that results in selection data. This indicates that the owner + // will send the actual data incrementally. The contents of the INCR + // property will be an integer, which represents a lower bound on the + // number of bytes of data in the selection. The requestor and the + // selection owner transfer the data in the selection in the following + // manner. The selection requestor starts the transfer process by + // deleting the (type==INCR) property forming the reply to the + // selection. + incr, err := xprop.Atm(request.requestor.Window().X, "INCR") + if err != nil { request.die(err); return } + if reply.Type == incr { + // reply to the INCR selection + err = xproto.DeletePropertyChecked ( + request.requestor.Window().X.Conn(), + request.requestor.Window().Id, + request.destination).Check() + if err != nil { request.die(err); return } + + // await the first chunk + request.state = selReqStateAwaitChunk + return + } + + // Once all the data in the selection has been retrieved (which may + // require getting the values of several properties &emdash; see section + // 2.7), the requestor should delete the property in the SelectionNotify + // request by using a GetProperty request with the delete argument set + // to True. As previously discussed, the owner has no way of knowing + // when the data has been transferred to the requestor unless the + // property is removed. + err = xproto.DeletePropertyChecked ( + request.requestor.Window().X.Conn(), + request.requestor.Window().Id, + request.destination).Check() + if err != nil { request.die(err); return } + + // depending on which state the selection request is in, do something + // different with the property's value + switch request.state { + case selReqStateAwaitValue: + // get the type from the property and convert that to the mime + // value to pass to the application. + targetName, err := xprop.AtomName ( + request.requestor.Window().X, reply.Type) + if err != nil { request.die(err); return } + + // we now have the full selection data in the property, so we + // finalize the request and are done. + reader := io.NopCloser(bytes.NewReader(reply.Value)) + request.finalize(Target(targetName), reader) + + case selReqStateAwaitTargets: + // make a list of the targets we got + buffer := reply.Value + atoms := make([]xproto.Atom, len(buffer) / 4) + for index := range atoms { + atoms[index] = xproto.Atom(xgb.Get32(buffer[index * 4:])) + } + targets := make([]Target, len(atoms)) + for index, atom := range atoms { + targetName, err := xprop.AtomName ( + request.requestor.Window().X, atom) + if err != nil { request.die(err); return } + targets[index] = Target(targetName) + } + + // choose the best target + var chosenAtom xproto.Atom + chosenTarget, ok := request.requestor.Choose(targets) + if ok { + for index, target := range targets { + if target == chosenTarget { + chosenAtom = atoms[index] + } + } + } + + if chosenAtom == 0 { + request.die(nil) + return + } + + // await the selection value + request.convertSelection(chosenAtom, selReqStateAwaitValue) + } +} + +// While the selection request is active, HandlePropertyNotify should be called +// when the requesting window recieves a PropertyNotify event. +func (request *Request) HandlePropertyNotify ( + connection *xgbutil.XUtil, + event xevent.PropertyNotifyEvent, +) { + // the only valid state that we can process a PropertyNotify event in + if request.state != selReqStateAwaitChunk { return } + if event.State != xproto.PropertyNewValue { return } + + request.handleINCRProperty(event.Atom) +} + +func (request *Request) handleINCRProperty (property xproto.Atom) { + // Retrieving data using GetProperty with the delete argument True. + reply, err := xproto.GetProperty ( + request.requestor.Window().X.Conn(), true, + request.requestor.Window().Id, property, xproto.GetPropertyTypeAny, + 0, (1 << 32) - 1).Reply() + if err != nil { request.die(err); return } + + if len(reply.Value) == 0 { + // a zero length property means the transfer has finished. we + // finalize the request with the data we have, and don't wait + // for more. + reader := io.NopCloser(bytes.NewReader(request.incrBuffer)) + request.finalize(request.incrTarget, reader) + + // we want to be extra sure we aren't holding onto this memory + request.incrBuffer = nil + } else { + // a property with content means the transfer is still ongoing. + // we append the data we got and wait for more. + request.state = selReqStateAwaitChunk + request.incrBuffer = append(request.incrBuffer, reply.Value...) + + targetName, err := xprop.AtomName ( + request.requestor.Window().X, reply.Type) + if err != nil { request.die(err); return } + request.incrTarget = Target(targetName) + } +}