diff options
Diffstat (limited to 'src/udev/udevadm-settle.c')
| -rw-r--r-- | src/udev/udevadm-settle.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/src/udev/udevadm-settle.c b/src/udev/udevadm-settle.c new file mode 100644 index 0000000..2bd5853 --- /dev/null +++ b/src/udev/udevadm-settle.c @@ -0,0 +1,226 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright © 2009 Canonical Ltd. + * Copyright © 2009 Scott James Remnant <scott@netsplit.com> + */ + +#include <errno.h> +#include <getopt.h> +#include <poll.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include "sd-bus.h" +#include "sd-login.h" +#include "sd-messages.h" + +#include "bus-util.h" +#include "io-util.h" +#include "libudev-util.h" +#include "string-util.h" +#include "strv.h" +#include "time-util.h" +#include "udev-ctrl.h" +#include "udevadm.h" +#include "unit-def.h" +#include "util.h" +#include "virt.h" + +static usec_t arg_timeout = 120 * USEC_PER_SEC; +static const char *arg_exists = NULL; + +static int help(void) { + printf("%s settle [OPTIONS]\n\n" + "Wait for pending udev events.\n\n" + " -h --help Show this help\n" + " -V --version Show package version\n" + " -t --timeout=SEC Maximum time to wait for events\n" + " -E --exit-if-exists=FILE Stop waiting if file exists\n" + , program_invocation_short_name); + + return 0; +} + +static int parse_argv(int argc, char *argv[]) { + static const struct option options[] = { + { "timeout", required_argument, NULL, 't' }, + { "exit-if-exists", required_argument, NULL, 'E' }, + { "version", no_argument, NULL, 'V' }, + { "help", no_argument, NULL, 'h' }, + { "seq-start", required_argument, NULL, 's' }, /* removed */ + { "seq-end", required_argument, NULL, 'e' }, /* removed */ + { "quiet", no_argument, NULL, 'q' }, /* removed */ + {} + }; + + int c, r; + + while ((c = getopt_long(argc, argv, "t:E:Vhs:e:q", options, NULL)) >= 0) { + switch (c) { + case 't': + r = parse_sec(optarg, &arg_timeout); + if (r < 0) + return log_error_errno(r, "Failed to parse timeout value '%s': %m", optarg); + break; + case 'E': + arg_exists = optarg; + break; + case 'V': + return print_version(); + case 'h': + return help(); + case 's': + case 'e': + case 'q': + return log_info_errno(SYNTHETIC_ERRNO(EINVAL), + "Option -%c no longer supported.", + c); + case '?': + return -EINVAL; + default: + assert_not_reached("Unknown option."); + } + } + + return 1; +} + +static int emit_deprecation_warning(void) { + _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; + _cleanup_strv_free_ char **a = NULL; + _cleanup_free_ char *unit = NULL; + int r; + + r = sd_pid_get_unit(0, &unit); + if (r < 0) { + log_debug_errno(r, "Failed to determine unit we run in, ignoring: %m"); + return 0; + } + + if (!streq(unit, "systemd-udev-settle.service")) + return 0; + + r = bus_connect_system_systemd(&bus); + if (r < 0) + log_debug_errno(r, "Failed to open connection to systemd, skipping dependency queries: %m"); + else { + _cleanup_strv_free_ char **b = NULL; + _cleanup_free_ char *unit_path = NULL; + + unit_path = unit_dbus_path_from_name("systemd-udev-settle.service"); + if (!unit_path) + return -ENOMEM; + + (void) sd_bus_get_property_strv( + bus, + "org.freedesktop.systemd1", + unit_path, + "org.freedesktop.systemd1.Unit", + "WantedBy", + NULL, + &a); + + (void) sd_bus_get_property_strv( + bus, + "org.freedesktop.systemd1", + unit_path, + "org.freedesktop.systemd1.Unit", + "RequiredBy", + NULL, + &b); + + r = strv_extend_strv(&a, b, true); + if (r < 0) + return r; + } + + if (strv_isempty(a)) + /* Print a simple message if we cannot determine the dependencies */ + log_notice("systemd-udev-settle.service is deprecated."); + else { + /* Print a longer, structured message if we can acquire the dependencies (this should be the + * common case). This is hooked up with a catalog entry and everything. */ + _cleanup_free_ char *t = NULL; + + t = strv_join(a, ", "); + if (!t) + return -ENOMEM; + + log_struct(LOG_NOTICE, + "MESSAGE=systemd-udev-settle.service is deprecated. Please fix %s not to pull it in.", t, + "OFFENDING_UNITS=%s", t, + "MESSAGE_ID=" SD_MESSAGE_SYSTEMD_UDEV_SETTLE_DEPRECATED_STR); + } + + return 0; +} + +int settle_main(int argc, char *argv[], void *userdata) { + _cleanup_(udev_queue_unrefp) struct udev_queue *queue = NULL; + usec_t deadline; + int r, fd; + + r = parse_argv(argc, argv); + if (r <= 0) + return r; + + if (running_in_chroot() > 0) { + log_info("Running in chroot, ignoring request."); + return 0; + } + + deadline = now(CLOCK_MONOTONIC) + arg_timeout; + + /* guarantee that the udev daemon isn't pre-processing */ + if (getuid() == 0) { + _cleanup_(udev_ctrl_unrefp) struct udev_ctrl *uctrl = NULL; + + if (udev_ctrl_new(&uctrl) >= 0) { + r = udev_ctrl_send_ping(uctrl); + if (r < 0) { + log_debug_errno(r, "Failed to connect to udev daemon: %m"); + return 0; + } + + r = udev_ctrl_wait(uctrl, MAX(5 * USEC_PER_SEC, arg_timeout)); + if (r < 0) + return log_error_errno(r, "Failed to wait for daemon to reply: %m"); + } + } + + queue = udev_queue_new(NULL); + if (!queue) + return log_error_errno(errno, "Failed to get udev queue: %m"); + + fd = udev_queue_get_fd(queue); + if (fd < 0) { + log_debug_errno(fd, "Queue is empty, nothing to watch: %m"); + return 0; + } + + (void) emit_deprecation_warning(); + + for (;;) { + if (arg_exists && access(arg_exists, F_OK) >= 0) + return 0; + + /* exit if queue is empty */ + if (udev_queue_get_queue_is_empty(queue)) + return 0; + + if (now(CLOCK_MONOTONIC) >= deadline) + return -ETIMEDOUT; + + /* wake up when queue becomes empty */ + r = fd_wait_for_event(fd, POLLIN, MSEC_PER_SEC); + if (r < 0) + return r; + if (r & POLLIN) { + r = udev_queue_flush(queue); + if (r < 0) + return log_error_errno(r, "Failed to flush queue: %m"); + } + } +} |