rfkill.c revision 6bedfcbb2970e06a4d3280c8fb62083d252ede73
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <linux/rfkill.h>
#include <poll.h>
#include "libudev.h"
#include "sd-daemon.h"
#include "escape.h"
#include "fd-util.h"
#include "fileio.h"
#include "io-util.h"
#include "mkdir.h"
#include "parse-util.h"
#include "string-util.h"
#include "udev-util.h"
#include "util.h"
#define EXIT_USEC (5 * USEC_PER_SEC)
static const char* const rfkill_type_table[NUM_RFKILL_TYPES] = {
[RFKILL_TYPE_ALL] = "all",
[RFKILL_TYPE_WLAN] = "wlan",
[RFKILL_TYPE_BLUETOOTH] = "bluetooth",
[RFKILL_TYPE_UWB] = "uwb",
[RFKILL_TYPE_WIMAX] = "wimax",
[RFKILL_TYPE_WWAN] = "wwan",
[RFKILL_TYPE_GPS] = "gps",
[RFKILL_TYPE_FM] = "fm",
[RFKILL_TYPE_NFC] = "nfc",
};
DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(rfkill_type, int);
static int find_device(
struct udev *udev,
const struct rfkill_event *event,
struct udev_device **ret) {
_cleanup_free_ char *sysname = NULL;
struct udev_device *device;
const char *name;
assert(udev);
assert(event);
assert(ret);
if (asprintf(&sysname, "rfkill%i", event->idx) < 0)
return log_oom();
device = udev_device_new_from_subsystem_sysname(udev, "rfkill", sysname);
if (!device)
return log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_ERR, errno, "Failed to open device: %m");
name = udev_device_get_sysattr_value(device, "name");
if (!name) {
log_debug("Device has no name, ignoring.");
udev_device_unref(device);
return -ENOENT;
}
log_debug("Operating on rfkill device '%s'.", name);
*ret = device;
return 0;
}
static int wait_for_initialized(
struct udev *udev,
struct udev_device *device,
struct udev_device **ret) {
_cleanup_udev_monitor_unref_ struct udev_monitor *monitor = NULL;
struct udev_device *d;
const char *sysname;
int watch_fd, r;
assert(udev);
assert(device);
assert(ret);
if (udev_device_get_is_initialized(device) != 0) {
*ret = udev_device_ref(device);
return 0;
}
assert_se(sysname = udev_device_get_sysname(device));
/* Wait until the device is initialized, so that we can get
* access to the ID_PATH property */
monitor = udev_monitor_new_from_netlink(udev, "udev");
if (!monitor)
return log_error_errno(errno, "Failed to acquire monitor: %m");
r = udev_monitor_filter_add_match_subsystem_devtype(monitor, "rfkill", NULL);
if (r < 0)
return log_error_errno(r, "Failed to add rfkill udev match to monitor: %m");
r = udev_monitor_enable_receiving(monitor);
if (r < 0)
return log_error_errno(r, "Failed to enable udev receiving: %m");
watch_fd = udev_monitor_get_fd(monitor);
if (watch_fd < 0)
return log_error_errno(watch_fd, "Failed to get watch fd: %m");
/* Check again, maybe things changed */
d = udev_device_new_from_subsystem_sysname(udev, "rfkill", sysname);
if (!d)
return log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_ERR, errno, "Failed to open device: %m");
if (udev_device_get_is_initialized(d) != 0) {
*ret = d;
return 0;
}
for (;;) {
_cleanup_udev_device_unref_ struct udev_device *t = NULL;
r = fd_wait_for_event(watch_fd, POLLIN, USEC_INFINITY);
if (r == -EINTR)
continue;
if (r < 0)
return log_error_errno(r, "Failed to watch udev monitor: %m");
t = udev_monitor_receive_device(monitor);
if (!t)
continue;
if (streq_ptr(udev_device_get_sysname(device), sysname)) {
*ret = udev_device_ref(t);
return 0;
}
}
}
static int determine_state_file(
struct udev *udev,
const struct rfkill_event *event,
struct udev_device *d,
char **ret) {
_cleanup_udev_device_unref_ struct udev_device *device = NULL;
const char *path_id, *type;
char *state_file;
int r;
assert(event);
assert(d);
assert(ret);
r = wait_for_initialized(udev, d, &device);
if (r < 0)
return r;
assert_se(type = rfkill_type_to_string(event->type));
path_id = udev_device_get_property_value(device, "ID_PATH");
if (path_id) {
_cleanup_free_ char *escaped_path_id = NULL;
escaped_path_id = cescape(path_id);
if (!escaped_path_id)
return log_oom();
state_file = strjoin("/var/lib/systemd/rfkill/", escaped_path_id, ":", type, NULL);
} else
state_file = strjoin("/var/lib/systemd/rfkill/", type, NULL);
if (!state_file)
return log_oom();
*ret = state_file;
return 0;
}
static int load_state(
int rfkill_fd,
struct udev *udev,
const struct rfkill_event *event) {
_cleanup_udev_device_unref_ struct udev_device *device = NULL;
_cleanup_free_ char *state_file = NULL, *value = NULL;
struct rfkill_event we;
ssize_t l;
int b, r;
assert(rfkill_fd >= 0);
assert(udev);
assert(event);
if (!shall_restore_state())
return 0;
r = find_device(udev, event, &device);
if (r < 0)
return r;
r = determine_state_file(udev, event, device, &state_file);
if (r < 0)
return r;
r = read_one_line_file(state_file, &value);
if (r == -ENOENT) {
/* No state file? Then save the current state */
r = write_string_file(state_file, one_zero(event->soft), WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
if (r < 0)
return log_error_errno(r, "Failed to write state file %s: %m", state_file);
log_debug("Saved state '%s' to %s.", one_zero(event->soft), state_file);
return 0;
}
if (r < 0)
return log_error_errno(r, "Failed to read state file %s: %m", state_file);
b = parse_boolean(value);
if (b < 0)
return log_error_errno(b, "Failed to parse state file %s: %m", state_file);
we = (struct rfkill_event) {
.op = RFKILL_OP_CHANGE,
.idx = event->idx,
.soft = b,
};
l = write(rfkill_fd, &we, sizeof(we));
if (l < 0)
return log_error_errno(errno, "Failed to restore rfkill state for %i: %m", event->idx);
if (l != sizeof(we)) {
log_error("Couldn't write rfkill event structure, too short.");
return -EIO;
}
log_debug("Loaded state '%s' from %s.", one_zero(b), state_file);
return 0;
}
static int save_state(
int rfkill_fd,
struct udev *udev,
const struct rfkill_event *event) {
_cleanup_udev_device_unref_ struct udev_device *device = NULL;
_cleanup_free_ char *state_file = NULL;
int r;
assert(rfkill_fd >= 0);
assert(udev);
assert(event);
r = find_device(udev, event, &device);
if (r < 0)
return r;
r = determine_state_file(udev, event, device, &state_file);
if (r < 0)
return r;
r = write_string_file(state_file, one_zero(event->soft), WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
if (r < 0)
return log_error_errno(r, "Failed to write state file %s: %m", state_file);
log_debug("Saved state '%s' to %s.", one_zero(event->soft), state_file);
return 0;
}
int main(int argc, char *argv[]) {
_cleanup_udev_unref_ struct udev *udev = NULL;
_cleanup_close_ int rfkill_fd = -1;
bool ready = false;
int r, n;
if (argc > 1) {
log_error("This program requires no arguments.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
udev = udev_new();
if (!udev) {
r = log_oom();
goto finish;
}
r = mkdir_p("/var/lib/systemd/rfkill", 0755);
if (r < 0) {
log_error_errno(r, "Failed to create rfkill directory: %m");
goto finish;
}
n = sd_listen_fds(false);
if (n < 0) {
r = log_error_errno(n, "Failed to determine whether we got any file descriptors passed: %m");
goto finish;
}
if (n > 1) {
log_error("Got too many file descriptors.");
r = -EINVAL;
goto finish;
}
if (n == 0) {
rfkill_fd = open("/dev/rfkill", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
if (rfkill_fd < 0) {
if (errno == ENOENT) {
log_debug_errno(errno, "Missing rfkill subsystem, or no device present, exiting.");
r = 0;
goto finish;
}
r = log_error_errno(errno, "Failed to open /dev/rfkill: %m");
goto finish;
}
} else {
rfkill_fd = SD_LISTEN_FDS_START;
r = fd_nonblock(rfkill_fd, 1);
if (r < 0) {
log_error_errno(r, "Failed to make /dev/rfkill socket non-blocking: %m");
goto finish;
}
}
for (;;) {
struct rfkill_event event;
const char *type;
ssize_t l;
l = read(rfkill_fd, &event, sizeof(event));
if (l < 0) {
if (errno == EAGAIN) {
if (!ready) {
/* Notify manager that we are
* now finished with
* processing whatever was
* queued */
(void) sd_notify(false, "READY=1");
ready = true;
}
/* Hang around for a bit, maybe there's more coming */
r = fd_wait_for_event(rfkill_fd, POLLIN, EXIT_USEC);
if (r == -EINTR)
continue;
if (r < 0) {
log_error_errno(r, "Failed to poll() on device: %m");
goto finish;
}
if (r > 0)
continue;
log_debug("All events read and idle, exiting.");
break;
}
log_error_errno(errno, "Failed to read from /dev/rfkill: %m");
}
if (l != RFKILL_EVENT_SIZE_V1) {
log_error("Read event structure of invalid size.");
r = -EIO;
goto finish;
}
type = rfkill_type_to_string(event.type);
if (!type) {
log_debug("An rfkill device of unknown type %i discovered, ignoring.", event.type);
continue;
}
switch (event.op) {
case RFKILL_OP_ADD:
log_debug("A new rfkill device has been added with index %i and type %s.", event.idx, type);
(void) load_state(rfkill_fd, udev, &event);
break;
case RFKILL_OP_DEL:
log_debug("An rfkill device has been removed with index %i and type %s", event.idx, type);
break;
case RFKILL_OP_CHANGE:
log_debug("An rfkill device has changed state with index %i and type %s", event.idx, type);
(void) save_state(rfkill_fd, udev, &event);
break;
default:
log_debug("Unknown event %i from /dev/rfkill for index %i and type %s, ignoring.", event.op, event.idx, type);
break;
}
}
r = 0;
finish:
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}