Add embedded VNC server with JWT auth, DXGI capture, and dashboard integration

client/vnc/server/capture_x11_shm_linux.go

@@ -0,0 +1,78 @@
+//go:build linux && !android
+
+package server
+
+import (
+	"fmt"
+	"image"
+
+	"github.com/jezek/xgb/shm"
+	"github.com/jezek/xgb/xproto"
+	"golang.org/x/sys/unix"
+)
+
+func (c *X11Capturer) initSHM() error {
+	if err := shm.Init(c.conn); err != nil {
+		return fmt.Errorf("init SHM extension: %w", err)
+	}
+
+	size := c.w * c.h * 4
+	id, err := unix.SysvShmGet(unix.IPC_PRIVATE, size, unix.IPC_CREAT|0600)
+	if err != nil {
+		return fmt.Errorf("shmget: %w", err)
+	}
+
+	addr, err := unix.SysvShmAttach(id, 0, 0)
+	if err != nil {
+		unix.SysvShmCtl(id, unix.IPC_RMID, nil)
+		return fmt.Errorf("shmat: %w", err)
+	}
+
+	unix.SysvShmCtl(id, unix.IPC_RMID, nil)
+
+	seg, err := shm.NewSegId(c.conn)
+	if err != nil {
+		unix.SysvShmDetach(addr)
+		return fmt.Errorf("new SHM seg: %w", err)
+	}
+
+	if err := shm.AttachChecked(c.conn, seg, uint32(id), false).Check(); err != nil {
+		unix.SysvShmDetach(addr)
+		return fmt.Errorf("SHM attach to X: %w", err)
+	}
+
+	c.shmID = id
+	c.shmAddr = addr
+	c.shmSeg = uint32(seg)
+	c.useSHM = true
+	return nil
+}
+
+func (c *X11Capturer) captureSHM() (*image.RGBA, error) {
+	cookie := shm.GetImage(c.conn, xproto.Drawable(c.screen.Root),
+		0, 0, uint16(c.w), uint16(c.h), 0xFFFFFFFF,
+		xproto.ImageFormatZPixmap, shm.Seg(c.shmSeg), 0)
+
+	_, err := cookie.Reply()
+	if err != nil {
+		return nil, fmt.Errorf("SHM GetImage: %w", err)
+	}
+
+	img := image.NewRGBA(image.Rect(0, 0, c.w, c.h))
+	n := c.w * c.h * 4
+
+	for i := 0; i < n; i += 4 {
+		img.Pix[i+0] = c.shmAddr[i+2] // R
+		img.Pix[i+1] = c.shmAddr[i+1] // G
+		img.Pix[i+2] = c.shmAddr[i+0] // B
+		img.Pix[i+3] = 0xff
+	}
+	return img, nil
+}
+
+func (c *X11Capturer) closeSHM() {
+	if c.useSHM {
+		shm.Detach(c.conn, shm.Seg(c.shmSeg))
+		unix.SysvShmDetach(c.shmAddr)
+	}
+}