diff options
Diffstat (limited to 'nexgb/shm')
| -rw-r--r-- | nexgb/shm/shm.go | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/nexgb/shm/shm.go b/nexgb/shm/shm.go index 3e086c4..e5841ca 100644 --- a/nexgb/shm/shm.go +++ b/nexgb/shm/shm.go @@ -276,6 +276,70 @@ func attachRequest(c *xgb.Conn, Shmseg Seg, Shmid uint32, ReadOnly bool) []byte return buf } +// AttachFdCookie is a cookie used only for AttachFd requests. +type AttachFdCookie struct { + *xgb.Cookie +} + +// AttachFd sends an unchecked request. +// If an error occurs, it can only be retrieved using xgb.WaitForEvent or xgb.PollForEvent. +func AttachFd(c *xgb.Conn, Shmseg Seg, ReadOnly bool) AttachFdCookie { + if _, ok := c.Extensions["MIT-SHM"]; !ok { + panic("Cannot issue request 'AttachFd' using the uninitialized extension 'MIT-SHM'. shm.Init(connObj) must be called first.") + } + cookie := c.NewCookie(false, false) + c.NewRequest(attachFdRequest(c, Shmseg, ReadOnly), cookie) + return AttachFdCookie{cookie} +} + +// AttachFdChecked sends a checked request. +// If an error occurs, it can be retrieved using AttachFdCookie.Check() +func AttachFdChecked(c *xgb.Conn, Shmseg Seg, ReadOnly bool) AttachFdCookie { + if _, ok := c.Extensions["MIT-SHM"]; !ok { + panic("Cannot issue request 'AttachFd' using the uninitialized extension 'MIT-SHM'. shm.Init(connObj) must be called first.") + } + cookie := c.NewCookie(true, false) + c.NewRequest(attachFdRequest(c, Shmseg, ReadOnly), cookie) + return AttachFdCookie{cookie} +} + +// Check returns an error if one occurred for checked requests that are not expecting a reply. +// This cannot be called for requests expecting a reply, nor for unchecked requests. +func (cook AttachFdCookie) Check() error { + return cook.Cookie.Check() +} + +// Write request to wire for AttachFd +// attachFdRequest writes a AttachFd request to a byte slice. +func attachFdRequest(c *xgb.Conn, Shmseg Seg, ReadOnly bool) []byte { + size := 12 + b := 0 + buf := make([]byte, size) + + buf[b] = c.Extensions["MIT-SHM"] + b += 1 + + buf[b] = 6 // request opcode + b += 1 + + xgb.Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units + b += 2 + + xgb.Put32(buf[b:], uint32(Shmseg)) + b += 4 + + if ReadOnly { + buf[b] = 1 + } else { + buf[b] = 0 + } + b += 1 + + b += 3 // padding + + return buf +} + // CreatePixmapCookie is a cookie used only for CreatePixmap requests. type CreatePixmapCookie struct { *xgb.Cookie @@ -351,6 +415,106 @@ func createPixmapRequest(c *xgb.Conn, Pid xproto.Pixmap, Drawable xproto.Drawabl return buf } +// CreateSegmentCookie is a cookie used only for CreateSegment requests. +type CreateSegmentCookie struct { + *xgb.Cookie +} + +// CreateSegment sends a checked request. +// If an error occurs, it will be returned with the reply by calling CreateSegmentCookie.Reply() +func CreateSegment(c *xgb.Conn, Shmseg Seg, Size uint32, ReadOnly bool) CreateSegmentCookie { + if _, ok := c.Extensions["MIT-SHM"]; !ok { + panic("Cannot issue request 'CreateSegment' using the uninitialized extension 'MIT-SHM'. shm.Init(connObj) must be called first.") + } + cookie := c.NewCookie(true, true) + c.NewRequest(createSegmentRequest(c, Shmseg, Size, ReadOnly), cookie) + return CreateSegmentCookie{cookie} +} + +// CreateSegmentUnchecked sends an unchecked request. +// If an error occurs, it can only be retrieved using xgb.WaitForEvent or xgb.PollForEvent. +func CreateSegmentUnchecked(c *xgb.Conn, Shmseg Seg, Size uint32, ReadOnly bool) CreateSegmentCookie { + if _, ok := c.Extensions["MIT-SHM"]; !ok { + panic("Cannot issue request 'CreateSegment' using the uninitialized extension 'MIT-SHM'. shm.Init(connObj) must be called first.") + } + cookie := c.NewCookie(false, true) + c.NewRequest(createSegmentRequest(c, Shmseg, Size, ReadOnly), cookie) + return CreateSegmentCookie{cookie} +} + +// CreateSegmentReply represents the data returned from a CreateSegment request. +type CreateSegmentReply struct { + Sequence uint16 // sequence number of the request for this reply + Length uint32 // number of bytes in this reply + Nfd byte + // padding: 24 bytes +} + +// Reply blocks and returns the reply data for a CreateSegment request. +func (cook CreateSegmentCookie) Reply() (*CreateSegmentReply, error) { + buf, err := cook.Cookie.Reply() + if err != nil { + return nil, err + } + if buf == nil { + return nil, nil + } + return createSegmentReply(buf), nil +} + +// createSegmentReply reads a byte slice into a CreateSegmentReply value. +func createSegmentReply(buf []byte) *CreateSegmentReply { + v := new(CreateSegmentReply) + b := 1 // skip reply determinant + + v.Nfd = buf[b] + b += 1 + + v.Sequence = xgb.Get16(buf[b:]) + b += 2 + + v.Length = xgb.Get32(buf[b:]) // 4-byte units + b += 4 + + b += 24 // padding + + return v +} + +// Write request to wire for CreateSegment +// createSegmentRequest writes a CreateSegment request to a byte slice. +func createSegmentRequest(c *xgb.Conn, Shmseg Seg, Size uint32, ReadOnly bool) []byte { + size := 16 + b := 0 + buf := make([]byte, size) + + buf[b] = c.Extensions["MIT-SHM"] + b += 1 + + buf[b] = 7 // request opcode + b += 1 + + xgb.Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units + b += 2 + + xgb.Put32(buf[b:], uint32(Shmseg)) + b += 4 + + xgb.Put32(buf[b:], Size) + b += 4 + + if ReadOnly { + buf[b] = 1 + } else { + buf[b] = 0 + } + b += 1 + + b += 3 // padding + + return buf +} + // DetachCookie is a cookie used only for Detach requests. type DetachCookie struct { *xgb.Cookie |