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src/xwindow.c

@@ -0,0 +1,102 @@
+#include "xwindow.h"
+
+#include <xcb/xcb_aux.h>
+
+#include "utils.h"
+#include "wm.h"
+#include "xcursor.h"
+
+xcb_window_t xwindow_create_bar_window(area_t area, uint32_t background_argb,
+                                       cursor_t cursor) {
+  static xcb_colormap_t colormap = XCB_NONE;
+  visual_t *visual = xwindow_get_xcb_visual(true);
+  xcb_visualid_t visual_id = visual->visual->visual_id;
+  xcb_connection_t *conn = wm.xcb_conn;
+  if (colormap == XCB_NONE) {
+    colormap = xcb_generate_id(conn);
+    uint8_t alloc = XCB_COLORMAP_ALLOC_NONE;
+    xcb_create_colormap(conn, alloc, colormap, wm.screen->root, visual_id);
+  }
+
+  xcb_window_t window = xcb_generate_id(conn);
+  uint32_t value_mask = XCB_CW_OVERRIDE_REDIRECT | XCB_CW_BACK_PIXEL |
+                        XCB_CW_BORDER_PIXEL | XCB_CW_EVENT_MASK |
+                        XCB_CW_CURSOR | XCB_CW_COLORMAP;
+  const xcb_create_window_value_list_t value_list = {
+    .override_redirect = true,
+    .background_pixel = background_argb,
+    .border_pixel = 0,
+    .event_mask = XCB_EVENT_MASK_BUTTON_PRESS | XCB_EVENT_MASK_EXPOSURE,
+    .cursor = xcursor_get_xcb_cursor(cursor),
+    .colormap = colormap,
+  };
+  xcb_void_cookie_t cookie;
+  cookie = xcb_create_window_aux_checked(
+    conn, visual->depth, window, wm.screen->root, area.x, area.y, area.width,
+    area.height, 0, XCB_WINDOW_CLASS_INPUT_OUTPUT, visual_id, value_mask,
+    &value_list);
+  p_delete(&visual);
+  if (xcb_request_check(conn, cookie)) fatal("cannot create bar window");
+
+  cookie = xcb_map_window(conn, window);
+  if (xcb_request_check(conn, cookie)) fatal("cannot map bar window:");
+
+  xcb_aux_sync(conn);
+
+  return window;
+}
+
+static visual_t *find_alpha_visual() {
+  xcb_depth_iterator_t depth_iter;
+  depth_iter = xcb_screen_allowed_depths_iterator(wm.screen);
+  for (; depth_iter.rem; xcb_depth_next(&depth_iter)) {
+    if (depth_iter.data->depth != 32) continue;
+
+    xcb_visualtype_iterator_t visual_iter;
+    visual_iter = xcb_depth_visuals_iterator(depth_iter.data);
+    for (; visual_iter.rem; xcb_visualtype_next(&visual_iter)) {
+      if (visual_iter.data->_class == XCB_VISUAL_CLASS_TRUE_COLOR) {
+        visual_t *r = p_new(visual_t, 1);
+        r->visual = visual_iter.data;
+        r->depth = depth_iter.data->depth;
+        return r;
+      }
+    }
+  }
+
+  return NULL;
+}
+
+static visual_t *find_root_visual() {
+  xcb_depth_iterator_t depth_iter;
+  depth_iter = xcb_screen_allowed_depths_iterator(wm.screen);
+  xcb_visualid_t vid = wm.screen->root_visual;
+  for (; depth_iter.rem; xcb_depth_next(&depth_iter)) {
+    xcb_visualtype_iterator_t visual_iter;
+    visual_iter = xcb_depth_visuals_iterator(depth_iter.data);
+    for (; visual_iter.rem; xcb_visualtype_next(&visual_iter)) {
+      if (visual_iter.data->visual_id == vid) {
+        visual_t *r = p_new(visual_t, 1);
+        r->visual = visual_iter.data;
+        r->depth = depth_iter.data->depth;
+        return r;
+      }
+    }
+  }
+
+  return NULL;
+}
+
+/**
+ * @brief 获取 xcb 的 visual 及其对应的 depth
+ * @param prefer_alpha 支持 alpha 的 visual 优先
+ * @returns 返回的信息使用后记得使用 free 释放
+ */
+visual_t *xwindow_get_xcb_visual(bool prefer_alpha) {
+  if (!prefer_alpha) return find_root_visual();
+
+  visual_t *visual = find_alpha_visual();
+  if (visual == NULL) visual = find_root_visual();
+
+  return visual;
+}