qwikndutty xcursor support for moving and resizing windows

bspwm-xcursor.diff

diff '--color=always' -ruN a/Makefile b/Makefile
--- a/Makefile	2023-08-14 18:21:17.209838188 -0400
+++ b/Makefile	2023-08-14 18:21:34.750469059 -0400
@@ -4,7 +4,7 @@
 CPPFLAGS += -D_POSIX_C_SOURCE=200809L -DVERSION=\"$(VERSION)\"
 CFLAGS   += -std=c99 -pedantic -Wall -Wextra -DJSMN_STRICT
 LDFLAGS  ?=
-LDLIBS    = $(LDFLAGS) -lm -lxcb -lxcb-util -lxcb-keysyms -lxcb-icccm -lxcb-ewmh -lxcb-randr -lxcb-xinerama -lxcb-shape
+LDLIBS    = $(LDFLAGS) -lm -lxcb -lxcb-util -lxcb-keysyms -lxcb-icccm -lxcb-ewmh -lxcb-randr -lxcb-xinerama -lxcb-shape -lxcb-cursor
 
 PREFIX    ?= /usr/local
 BINPREFIX ?= $(PREFIX)/bin
diff '--color=always' -ruN a/src/bspwm.c b/src/bspwm.c
--- a/src/bspwm.c	2023-08-14 18:21:17.209838188 -0400
+++ b/src/bspwm.c	2023-08-14 18:21:34.550462579 -0400
@@ -37,6 +37,7 @@
 #include <string.h>
 #include <xcb/xinerama.h>
 #include <xcb/xcb_aux.h>
+#include <xcb/xcb_cursor.h>
 #include "types.h"
 #include "desktop.h"
 #include "monitor.h"
@@ -453,6 +454,7 @@
 		clear_input_focus();
 	}
 	free(ifo);
+    xcursor_load_cursors();
 }
 
 void register_events(void)
@@ -486,6 +488,7 @@
 	}
 
 	empty_history();
+    xcb_cursor_context_free(cursor_context);
 }
 
 bool check_connection (xcb_connection_t *dpy)
diff '--color=always' -ruN a/src/bspwm.h b/src/bspwm.h
--- a/src/bspwm.h	2023-08-14 18:21:17.209838188 -0400
+++ b/src/bspwm.h	2023-08-14 18:21:34.560462903 -0400
@@ -26,6 +26,7 @@
 #define BSPWM_BSPWM_H
 
 #include "types.h"
+#include "xcb/xcb_cursor.h"
 
 #define WM_NAME                  "bspwm"
 #define CONFIG_NAME              WM_NAME "rc"
diff '--color=always' -ruN a/src/pointer.c b/src/pointer.c
--- a/src/pointer.c	2023-08-14 18:21:17.209838188 -0400
+++ b/src/pointer.c	2023-08-14 18:21:34.607131082 -0400
@@ -35,6 +35,7 @@
 #include "events.h"
 #include "window.h"
 #include "pointer.h"
+#include <assert.h>
 
 uint16_t num_lock;
 uint16_t caps_lock;
@@ -43,6 +44,9 @@
 bool grabbing;
 node_t *grabbed_node;
 
+xcb_cursor_context_t *cursor_context;
+xcb_cursor_t cursors[CURSOR_MAX];
+
 void pointer_init(void)
 {
 	num_lock = modfield_from_keysym(XK_Num_Lock);
@@ -237,7 +241,45 @@
 		return true;
 	}
 
-	xcb_grab_pointer_reply_t *reply = xcb_grab_pointer_reply(dpy, xcb_grab_pointer(dpy, 0, root, XCB_EVENT_MASK_BUTTON_RELEASE|XCB_EVENT_MASK_BUTTON_MOTION, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC, XCB_NONE, XCB_NONE, XCB_CURRENT_TIME), NULL);
+    resize_handle_t rh = get_handle(loc.node, pos, pac);
+
+    int cursor = 0;
+    if (pac == ACTION_MOVE) {
+        cursor = CURSOR_MOVE;
+    } else if (pac == ACTION_RESIZE_SIDE || pac == ACTION_RESIZE_CORNER) {
+        cursor = CURSOR_X;
+        if (loc.node->client->state == STATE_TILED) {
+            if (rh & HANDLE_LEFT) {
+                if (find_fence(loc.node, DIR_WEST) == NULL)
+                    rh ^= HANDLE_LEFT;
+            } else if (rh & HANDLE_RIGHT) {
+                if (find_fence(loc.node, DIR_EAST) == NULL)
+                    rh ^= HANDLE_RIGHT;
+            }
+            if (rh & HANDLE_TOP) {
+                if (find_fence(loc.node, DIR_NORTH) == NULL)
+                    rh ^= HANDLE_TOP;
+            } else if (rh & HANDLE_BOTTOM) {
+                if (find_fence(loc.node, DIR_SOUTH) == NULL)
+                    rh ^= HANDLE_BOTTOM;
+            }
+        }
+        if (rh == HANDLE_TOP_LEFT || rh == HANDLE_BOTTOM_RIGHT) {
+            cursor = CURSOR_RESIZE_TL;
+        } else if (rh == HANDLE_TOP_RIGHT || rh == HANDLE_BOTTOM_LEFT) {
+            cursor = CURSOR_RESIZE_TR;
+        } else {
+            if (rh & (HANDLE_TOP | HANDLE_BOTTOM)) {
+                cursor = CURSOR_RESIZE_V;
+            } else if (rh & (HANDLE_LEFT | HANDLE_RIGHT)) {
+                cursor = CURSOR_RESIZE_H;
+            }
+        }
+    }
+    xcb_cursor_t xcursor = cursor ? xcursor_get_cursor(cursor) : XCB_NONE;
+
+    xcb_grab_pointer_cookie_t cookie = xcb_grab_pointer(dpy, 0, root, XCB_EVENT_MASK_BUTTON_RELEASE|XCB_EVENT_MASK_BUTTON_MOTION, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC, XCB_NONE, xcursor, XCB_CURRENT_TIME);
+	xcb_grab_pointer_reply_t *reply = xcb_grab_pointer_reply(dpy, cookie, NULL);
 
 	if (reply == NULL || reply->status != XCB_GRAB_STATUS_SUCCESS) {
 		free(reply);
@@ -253,15 +295,14 @@
 		put_status(SBSC_MASK_POINTER_ACTION, "pointer_action 0x%08X 0x%08X 0x%08X resize_side begin\n", loc.monitor->id, loc.desktop->id, loc.node->id);
 	}
 
-	track_pointer(loc, pac, pos);
+	track_pointer(loc, pac, pos, rh);
 
 	return true;
 }
 
-void track_pointer(coordinates_t loc, pointer_action_t pac, xcb_point_t pos)
+void track_pointer(coordinates_t loc, pointer_action_t pac, xcb_point_t pos, resize_handle_t rh)
 {
 	node_t *n = loc.node;
-	resize_handle_t rh = get_handle(loc.node, pos, pac);
 
 	uint16_t last_motion_x = pos.x, last_motion_y = pos.y;
 	xcb_timestamp_t last_motion_time = 0;
@@ -312,7 +353,7 @@
 	if (grabbed_node == NULL) {
 		grabbing = false;
 		return;
-	}
+    }
 
 	if (pac == ACTION_MOVE) {
 		put_status(SBSC_MASK_POINTER_ACTION, "pointer_action 0x%08X 0x%08X 0x%08X move end\n", loc.monitor->id, loc.desktop->id, n->id);
@@ -338,3 +379,29 @@
 		}
 	}
 }
+
+void xcursor_load_cursors(void) {
+    if (xcb_cursor_context_new(dpy, screen, &cursor_context) < 0) {
+        warn("Couldn't create the cursor context.\n");
+    }
+#define LOAD_CURSOR(constant, name)                            \
+    do {                                                       \
+        cursors[constant] = xcb_cursor_load_cursor(cursor_context, name); \
+    } while (0)
+    LOAD_CURSOR(CURSOR_POINTER, "left_ptr");
+    LOAD_CURSOR(CURSOR_RESIZE_H, "sb_h_double_arrow");
+    LOAD_CURSOR(CURSOR_RESIZE_V, "sb_v_double_arrow");
+    LOAD_CURSOR(CURSOR_MOVE, "fleur");
+    LOAD_CURSOR(CURSOR_RESIZE_TL, "top_left_corner");
+    LOAD_CURSOR(CURSOR_RESIZE_TR, "top_right_corner");
+    LOAD_CURSOR(CURSOR_RESIZE_BL, "bottom_left_corner");
+    LOAD_CURSOR(CURSOR_RESIZE_BR, "bottom_right_corner");
+    LOAD_CURSOR(CURSOR_X, "X_cursor");
+#undef LOAD_CURSOR
+}
+
+
+xcb_cursor_t xcursor_get_cursor(enum xcursor_cursor_t c) {
+    assert(c < CURSOR_MAX);
+    return cursors[c];
+}
diff '--color=always' -ruN a/src/pointer.h b/src/pointer.h
--- a/src/pointer.h	2023-08-14 18:21:17.209838188 -0400
+++ b/src/pointer.h	2023-08-14 18:21:34.607131082 -0400
@@ -21,6 +21,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
+#include <xcb/xcb_cursor.h>
 
 #ifndef BSPWM_POINTER_H
 #define BSPWM_POINTER_H
@@ -29,6 +30,20 @@
 #define XK_Caps_Lock    0xffe5
 #define XK_Scroll_Lock  0xff14
 
+extern enum xcursor_cursor_t {
+    CURSOR_POINTER = 0,
+    CURSOR_RESIZE_H,
+    CURSOR_RESIZE_V,
+    CURSOR_RESIZE_TL,
+    CURSOR_RESIZE_TR,
+    CURSOR_RESIZE_BL,
+    CURSOR_RESIZE_BR,
+    CURSOR_MOVE,
+    CURSOR_X,
+    CURSOR_MAX
+};
+
+
 extern uint16_t num_lock;
 extern uint16_t caps_lock;
 extern uint16_t scroll_lock;
@@ -36,6 +51,8 @@
 extern bool grabbing;
 extern node_t *grabbed_node;
 
+extern xcb_cursor_context_t *cursor_context;
+
 void pointer_init(void);
 void window_grab_buttons(xcb_window_t win);
 void window_grab_button(xcb_window_t win, uint8_t button, uint16_t modifier);
@@ -44,6 +61,8 @@
 int16_t modfield_from_keysym(xcb_keysym_t keysym);
 resize_handle_t get_handle(node_t *n, xcb_point_t pos, pointer_action_t pac);
 bool grab_pointer(pointer_action_t pac);
-void track_pointer(coordinates_t loc, pointer_action_t pac, xcb_point_t pos);
+void track_pointer(coordinates_t loc, pointer_action_t pac, xcb_point_t pos, resize_handle_t rh);
+void xcursor_load_cursors(void);
+xcb_cursor_t xcursor_get_cursor(enum xcursor_cursor_t c);
 
 #endif
diff '--color=always' -ruN a/src/window.c b/src/window.c
--- a/src/window.c	2023-08-14 18:21:17.209838188 -0400
+++ b/src/window.c	2023-08-14 18:21:34.653799260 -0400
@@ -27,6 +27,7 @@
 #include <stdbool.h>
 #include <string.h>
 #include <xcb/shape.h>
+#include <xcb/xcb_cursor.h>
 #include "bspwm.h"
 #include "ewmh.h"
 #include "monitor.h"
@@ -917,6 +918,13 @@
 	window_set_visibility(win, true);
 }
 
+void window_set_cursor(xcb_window_t win, char *name)
+{
+    xcb_cursor_t cursor = xcb_cursor_load_cursor(cursor_context, name);
+    uint32_t values[] = {cursor};
+    xcb_change_window_attributes(dpy, win, XCB_CW_CURSOR, values);
+}
+
 void update_input_focus(void)
 {
 	set_input_focus(mon->desk->focus);
diff '--color=always' -ruN a/src/window.h b/src/window.h
--- a/src/window.h	2023-08-14 18:21:17.209838188 -0400
+++ b/src/window.h	2023-08-14 18:21:34.657132703 -0400
@@ -68,6 +68,7 @@
 void window_set_visibility(xcb_window_t win, bool visible);
 void window_hide(xcb_window_t win);
 void window_show(xcb_window_t win);
+void window_set_cursor(xcb_window_t, char *);
 void update_input_focus(void);
 void set_input_focus(node_t *n);
 void clear_input_focus(void);