picom/src/x.h

// SPDX-License-Identifier: MPL-2.0
// Copyright (c) 2018 Yuxuan Shui <yshuiv7@gmail.com>
#pragma once
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <xcb/xcb.h>
#include <xcb/render.h>
#include <xcb/sync.h>
#include <xcb/xfixes.h>
#include <xcb/xcb_renderutil.h>

#include "compiler.h"
#include "region.h"

typedef struct session session_t;

/// Structure representing Window property value.
typedef struct winprop {
  union {
    void *ptr;
    int8_t *p8;
    int16_t *p16;
    int32_t *p32;
    uint32_t *c32; // 32bit cardinal
  };
  unsigned long nitems;
  xcb_atom_t type;
  int format;

  xcb_get_property_reply_t *r;
} winprop_t;

#define XCB_SYNCED_VOID(func, c, ...) xcb_request_check(c, func##_checked(c, __VA_ARGS__));
#define XCB_SYNCED(func, c, ...) ({ \
  xcb_generic_error_t *e = NULL; \
  __auto_type r = func##_reply(c, func(c, __VA_ARGS__), &e); \
  if (e) { \
    x_print_error(e->sequence, e->major_code, e->minor_code, e->error_code); \
    free(e); \
  } \
  r; \
})

/**
 * Send a request to X server and get the reply to make sure all previous
 * requests are processed, and their replies received
 *
 * xcb_get_input_focus is used here because it is the same request used by
 * libX11
 */
static inline void
x_sync(xcb_connection_t *c) {
  free(xcb_get_input_focus_reply(c, xcb_get_input_focus(c), NULL));
}

/**
 * Get a specific attribute of a window.
 *
 * Returns a blank structure if the returned type and format does not
 * match the requested type and format.
 *
 * @param ps current session
 * @param w window
 * @param atom atom of attribute to fetch
 * @param length length to read
 * @param rtype atom of the requested type
 * @param rformat requested format
 * @return a <code>winprop_t</code> structure containing the attribute
 *    and number of items. A blank one on failure.
 */
winprop_t
wid_get_prop_adv(const session_t *ps, xcb_window_t w, xcb_atom_t atom, long offset,
    long length, xcb_atom_t rtype, int rformat);

/**
 * Wrapper of wid_get_prop_adv().
 */
static inline winprop_t
wid_get_prop(const session_t *ps, xcb_window_t wid, xcb_atom_t atom, long length,
    xcb_atom_t rtype, int rformat) {
  return wid_get_prop_adv(ps, wid, atom, 0L, length, rtype, rformat);
}

/**
 * Get the value of a type-<code>xcb_window_t</code> property of a window.
 *
 * @return the value if successful, 0 otherwise
 */
xcb_window_t
wid_get_prop_window(session_t *ps, xcb_window_t wid, xcb_atom_t aprop);

/**
 * Get the value of a text property of a window.
 */
bool wid_get_text_prop(session_t *ps, xcb_window_t wid, xcb_atom_t prop,
    char ***pstrlst, int *pnstr);

xcb_render_pictforminfo_t *x_get_pictform_for_visual(session_t *, xcb_visualid_t);

xcb_render_picture_t x_create_picture_with_pictfmt_and_pixmap(
  session_t *ps, xcb_render_pictforminfo_t *pictfmt,
  xcb_pixmap_t pixmap, unsigned long valuemask,
  const xcb_render_create_picture_value_list_t *attr)
attr_nonnull(1, 2);

xcb_render_picture_t x_create_picture_with_visual_and_pixmap(
  session_t *ps, xcb_visualid_t visual,
  xcb_pixmap_t pixmap, unsigned long valuemask,
  const xcb_render_create_picture_value_list_t *attr)
attr_nonnull(1);

xcb_render_picture_t x_create_picture_with_standard_and_pixmap(
  session_t *ps, xcb_pict_standard_t standard,
  xcb_pixmap_t pixmap, unsigned long valuemask,
  const xcb_render_create_picture_value_list_t *attr)
attr_nonnull(1);

/**
 * Create an picture.
 */
xcb_render_picture_t
x_create_picture_with_pictfmt(session_t *ps, int wid, int hei,
  xcb_render_pictforminfo_t *pictfmt, unsigned long valuemask,
  const xcb_render_create_picture_value_list_t *attr);

xcb_render_picture_t
x_create_picture_with_visual(session_t *ps, int w, int h,
  xcb_visualid_t visual, unsigned long valuemask,
  const xcb_render_create_picture_value_list_t *attr);

/// Fetch a X region and store it in a pixman region
bool x_fetch_region(session_t *ps, xcb_xfixes_region_t r, region_t *res);

void x_set_picture_clip_region(session_t *ps, xcb_render_picture_t,
  int clip_x_origin, int clip_y_origin, const region_t *);

void x_clear_picture_clip_region(session_t *ps, xcb_render_picture_t pict);

/**
 * X11 error handler function.
 *
 * XXX consider making this error to string
 */
void
x_print_error(unsigned long serial, uint8_t major, uint8_t minor, uint8_t error_code);

xcb_pixmap_t
x_create_pixmap(session_t *ps, uint8_t depth, xcb_drawable_t drawable, uint16_t width, uint16_t height);

bool
x_validate_pixmap(session_t *ps, xcb_pixmap_t pxmap);

/**
 * Free a <code>winprop_t</code>.
 *
 * @param pprop pointer to the <code>winprop_t</code> to free.
 */
static inline void
free_winprop(winprop_t *pprop) {
  // Empty the whole structure to avoid possible issues
  if (pprop->r)
    free(pprop->r);
  pprop->ptr = NULL;
  pprop->r = NULL;
  pprop->nitems = 0;
}
/// Get the back pixmap of the root window
xcb_pixmap_t x_get_root_back_pixmap(session_t *ps);

/// Return true if the atom refers to a property name that is used for the
/// root window background pixmap
bool x_atom_is_background_prop(session_t *ps, xcb_atom_t atom);

bool x_fence_sync(session_t *, xcb_sync_fence_t);