93 lines
3.0 KiB
C
93 lines
3.0 KiB
C
/*
|
||
* vim:ts=4:sw=4:expandtab
|
||
*
|
||
* i3 - an improved dynamic tiling window manager
|
||
* © 2009 Michael Stapelberg and contributors (see also: LICENSE)
|
||
*
|
||
*/
|
||
#include "libi3.h"
|
||
|
||
#include <math.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
|
||
#include <xcb/xcb.h>
|
||
#include <xcb/xcb_aux.h>
|
||
|
||
/*
|
||
* Try to get the contents of the given atom (for example I3_SOCKET_PATH) from
|
||
* the X11 root window and return NULL if it doesn’t work.
|
||
*
|
||
* If the provided XCB connection is NULL, a new connection will be
|
||
* established.
|
||
*
|
||
* The memory for the contents is dynamically allocated and has to be
|
||
* free()d by the caller.
|
||
*
|
||
*/
|
||
char *root_atom_contents(const char *atomname, xcb_connection_t *provided_conn, int screen) {
|
||
xcb_intern_atom_cookie_t atom_cookie;
|
||
xcb_intern_atom_reply_t *atom_reply;
|
||
char *content = NULL;
|
||
size_t content_max_words = 256;
|
||
xcb_connection_t *conn = provided_conn;
|
||
|
||
if (provided_conn == NULL &&
|
||
((conn = xcb_connect(NULL, &screen)) == NULL ||
|
||
xcb_connection_has_error(conn))) {
|
||
return NULL;
|
||
}
|
||
|
||
atom_cookie = xcb_intern_atom(conn, 0, strlen(atomname), atomname);
|
||
|
||
xcb_screen_t *root_screen = xcb_aux_get_screen(conn, screen);
|
||
xcb_window_t root = root_screen->root;
|
||
|
||
atom_reply = xcb_intern_atom_reply(conn, atom_cookie, NULL);
|
||
if (atom_reply == NULL) {
|
||
goto out_conn;
|
||
}
|
||
|
||
xcb_get_property_cookie_t prop_cookie;
|
||
xcb_get_property_reply_t *prop_reply;
|
||
prop_cookie = xcb_get_property_unchecked(conn, false, root, atom_reply->atom,
|
||
XCB_GET_PROPERTY_TYPE_ANY, 0, content_max_words);
|
||
prop_reply = xcb_get_property_reply(conn, prop_cookie, NULL);
|
||
if (prop_reply == NULL) {
|
||
goto out_atom;
|
||
}
|
||
if (xcb_get_property_value_length(prop_reply) > 0 && prop_reply->bytes_after > 0) {
|
||
/* We received an incomplete value. Ask again but with a properly
|
||
* adjusted size. */
|
||
content_max_words += ceil(prop_reply->bytes_after / 4.0);
|
||
/* Repeat the request, with adjusted size */
|
||
free(prop_reply);
|
||
prop_cookie = xcb_get_property_unchecked(conn, false, root, atom_reply->atom,
|
||
XCB_GET_PROPERTY_TYPE_ANY, 0, content_max_words);
|
||
prop_reply = xcb_get_property_reply(conn, prop_cookie, NULL);
|
||
if (prop_reply == NULL) {
|
||
goto out_atom;
|
||
}
|
||
}
|
||
if (xcb_get_property_value_length(prop_reply) == 0) {
|
||
goto out;
|
||
}
|
||
if (prop_reply->type == XCB_ATOM_CARDINAL) {
|
||
/* We treat a CARDINAL as a >= 32-bit unsigned int. The only CARDINAL
|
||
* we query is I3_PID, which is 32-bit. */
|
||
sasprintf(&content, "%u", *((unsigned int *)xcb_get_property_value(prop_reply)));
|
||
} else {
|
||
sasprintf(&content, "%.*s", xcb_get_property_value_length(prop_reply),
|
||
(char *)xcb_get_property_value(prop_reply));
|
||
}
|
||
|
||
out:
|
||
free(prop_reply);
|
||
out_atom:
|
||
free(atom_reply);
|
||
out_conn:
|
||
if (provided_conn == NULL)
|
||
xcb_disconnect(conn);
|
||
return content;
|
||
}
|