gsr-overlay > gsr-ui

gsr-ui-daemon/main.c

@@ -0,0 +1,116 @@
+#include <stdio.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <X11/Xlib.h>
+#include <X11/keysym.h>
+
+bool exec_program(const char **args, pid_t *process_id) {
+    *process_id = -1;
+
+    /* 1 argument */
+    if(args[0] == NULL)
+        return false;
+
+    pid_t pid = vfork();
+    if(pid == -1) {
+        perror("Failed to vfork");
+        return false;
+    } else if(pid == 0) { /* child */
+        execvp(args[0], (char* const*)args);
+        perror("execvp");
+        _exit(127);
+    } else { /* parent */
+        *process_id = pid;
+    }
+
+    return true;
+}
+
+static int ignore_xerror(Display *display, XErrorEvent *ee) {
+    (void)display;
+    (void)ee;
+    return 0;
+}
+
+static void sigterm_handler(int dummy) {
+    (void)dummy;
+}
+
+static const KeySym toggle_overlay_key = XK_Z;
+static unsigned int toggle_overlay_modifiers = Mod1Mask;
+
+static void grab_keys(Display *display) {
+    unsigned int numlockmask = 0; 
+    KeyCode numlock_keycode = XKeysymToKeycode(display, XK_Num_Lock);
+    XModifierKeymap *modmap = XGetModifierMapping(display);
+    for(int i = 0; i < 8; ++i) {
+        for(int j = 0; j < modmap->max_keypermod; ++j) {
+            if(modmap->modifiermap[i * modmap->max_keypermod + j] == numlock_keycode)
+                numlockmask = (1 << i); 
+        }
+    }   
+    XFreeModifiermap(modmap);
+
+    XErrorHandler prev_error_handler = XSetErrorHandler(ignore_xerror);
+    
+    Window root_window = DefaultRootWindow(display);
+    unsigned int modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
+    for(int i = 0; i < 4; ++i) {
+        XGrabKey(display, XKeysymToKeycode(display, toggle_overlay_key), toggle_overlay_modifiers|modifiers[i], root_window, False, GrabModeAsync, GrabModeAsync);
+    }    
+    
+    XSync(display, False);
+    XSetErrorHandler(prev_error_handler);
+}
+
+int main(void) {
+    Display *display = XOpenDisplay(NULL);
+    if(!display) {
+        fprintf(stderr, "Error: XOpenDisplay failed\n");
+        return 1;
+    }
+
+    grab_keys(display);
+    const KeyCode overlay_keycode = XKeysymToKeycode(display, toggle_overlay_key);
+
+    XSetErrorHandler(ignore_xerror);
+    /* Killing gpu-screen-recorder with SIGTERM also gives us SIGTERM. We want to ignore that as that has no meaning here */
+    signal(SIGTERM, sigterm_handler);
+
+    pid_t overlay_pid = -1;
+
+    fprintf(stderr, "gsr overlay is now ready, waiting for inputs. Press alt+z to show/hide the overlay\n");
+
+    XEvent xev;
+    for(;;) {
+        XNextEvent(display, &xev);
+        if(xev.type == KeyPress && xev.xkey.keycode == overlay_keycode) {
+            if(overlay_pid != -1) {
+                int status;
+                if(waitpid(overlay_pid, &status, WNOHANG) == 0) {
+                    kill(overlay_pid, SIGINT);
+                    int status;
+                    if(waitpid(overlay_pid, &status, 0) == -1) {
+                        perror("waitpid failed");
+                        /* Ignore... */
+                    }
+                    overlay_pid = -1;
+                    continue;
+                } else {
+                    overlay_pid = -1;
+                }
+            }
+
+            if(overlay_pid == -1) {
+                fprintf(stderr, "launch overlay\n");
+                // TODO: window_with_input_focus
+                const char *args[] = { "gsr-overlay", NULL };
+                exec_program(args, &overlay_pid);
+            }
+        }
+    }
+    return 0;
+}

gsr-ui-daemon/project.conf

@@ -0,0 +1,11 @@
+[package]
+name = "gpu-screen-recorder-overlay-daemon"
+type = "executable"
+version = "0.1.0"
+platforms = ["posix"]
+
+[config]
+ignore_dirs = ["build"]
+
+[dependencies]
+x11 = ">=1"