Display error message when locking failed (#99)

[i3/i3lock] / xcb.c

diff --git a/xcb.c b/xcb.c
index f1a9a7680cbd7b2bcba89bbb9cc7ff6821ba5c17..e0b78111a06b3347371cd72ba88972bb462d64c4 100644 (file)
--- a/xcb.c
+++ b/xcb.c
@@ -10,6 +10,7 @@
 #include <xcb/xcb.h>
 #include <xcb/xcb_image.h>
 #include <xcb/xcb_atom.h>
+#include <xcb/xcb_aux.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdbool.h>
@@ -17,8 +18,12 @@
 #include <unistd.h>
 #include <assert.h>
 #include <err.h>
+#include <time.h>
 
 #include "cursors.h"
+#include "unlock_indicator.h"
+
+extern pam_state_t pam_state;
 
 xcb_connection_t *conn;
 xcb_screen_t *screen;
@@ -150,11 +155,14 @@ xcb_window_t open_fullscreen_window(xcb_connection_t *conn, xcb_screen_t *scr, c
     values[0] = XCB_STACK_MODE_ABOVE;
     xcb_configure_window(conn, win, XCB_CONFIG_WINDOW_STACK_MODE, values);
 
+    /* Ensure that the window is created and set up before returning */
+    xcb_aux_sync(conn);
+
     return win;
 }
 
 /*
- * Repeatedly tries to grab pointer and keyboard (up to 1000 times).
+ * Repeatedly tries to grab pointer and keyboard (up to 10000 times).
  *
  */
 void grab_pointer_and_keyboard(xcb_connection_t *conn, xcb_screen_t *screen, xcb_cursor_t cursor) {
@@ -166,6 +174,10 @@ void grab_pointer_and_keyboard(xcb_connection_t *conn, xcb_screen_t *screen, xcb
 
     int tries = 10000;
 
+    /* Using few variables to trigger a redraw_screen() if too many tries */
+    bool redrawn = false;
+    time_t start = clock();
+
     while (tries-- > 0) {
         pcookie = xcb_grab_pointer(
             conn,
@@ -186,6 +198,14 @@ void grab_pointer_and_keyboard(xcb_connection_t *conn, xcb_screen_t *screen, xcb
 
         /* Make this quite a bit slower */
         usleep(50);
+
+        /* Measure elapsed time and trigger a screen redraw if elapsed > 250000 */
+        if (!redrawn &&
+            (tries % 100) == 0 &&
+            (clock() - start) > 250000) {
+            redraw_screen();
+            redrawn = true;
+        }
     }
 
     while (tries-- > 0) {
@@ -205,10 +225,24 @@ void grab_pointer_and_keyboard(xcb_connection_t *conn, xcb_screen_t *screen, xcb
 
         /* Make this quite a bit slower */
         usleep(50);
+
+        /* Measure elapsed time and trigger a screen redraw if elapsed > 250000 */
+        if (!redrawn &&
+            (tries % 100) == 0 &&
+            (clock() - start) > 250000) {
+            redraw_screen();
+            redrawn = true;
+        }
     }
 
-    if (tries <= 0)
+    /* After trying for 10000 times, i3lock will display an error message
+     * for 2 sec prior to terminate. */
+    if (tries <= 0) {
+        pam_state = STATE_I3LOCK_LOCK_FAILED;
+        redraw_screen();
+        sleep(1);
         errx(EXIT_FAILURE, "Cannot grab pointer/keyboard");
+    }
 }
 
 xcb_cursor_t create_cursor(xcb_connection_t *conn, xcb_screen_t *screen, xcb_window_t win, int choice) {