+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2010 ProFUSION embedded systems
-
- 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 <sys/wait.h>
-#include <signal.h>
-#include <errno.h>
-#include <unistd.h>
-
-#include "util.h"
-#include "killall.h"
-#include "set.h"
-
-#define TIMEOUT_USEC (10 * USEC_PER_SEC)
-
-static bool ignore_proc(pid_t pid) {
- _cleanup_fclose_ FILE *f = NULL;
- char c;
- const char *p;
- size_t count;
- uid_t uid;
- int r;
-
- /* We are PID 1, let's not commit suicide */
- if (pid == 1)
- return true;
-
- r = get_process_uid(pid, &uid);
- if (r < 0)
- return true; /* not really, but better safe than sorry */
-
- /* Non-root processes otherwise are always subject to be killed */
- if (uid != 0)
- return false;
-
- p = procfs_file_alloca(pid, "cmdline");
- f = fopen(p, "re");
- if (!f)
- return true; /* not really, but has the desired effect */
-
- count = fread(&c, 1, 1, f);
-
- /* Kernel threads have an empty cmdline */
- if (count <= 0)
- return true;
-
- /* Processes with argv[0][0] = '@' we ignore from the killing
- * spree.
- *
- * http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons */
- if (count == 1 && c == '@')
- return true;
-
- return false;
-}
-
-static void wait_for_children(Set *pids, sigset_t *mask) {
- usec_t until;
-
- assert(mask);
-
- if (set_isempty(pids))
- return;
-
- until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC;
- for (;;) {
- struct timespec ts;
- int k;
- usec_t n;
- void *p;
- Iterator i;
-
- /* First, let the kernel inform us about killed
- * children. Most processes will probably be our
- * children, but some are not (might be our
- * grandchildren instead...). */
- for (;;) {
- pid_t pid;
-
- pid = waitpid(-1, NULL, WNOHANG);
- if (pid == 0)
- break;
- if (pid < 0) {
- if (errno == ECHILD)
- break;
-
- log_error_errno(errno, "waitpid() failed: %m");
- return;
- }
-
- set_remove(pids, ULONG_TO_PTR(pid));
- }
-
- /* Now explicitly check who might be remaining, who
- * might not be our child. */
- SET_FOREACH(p, pids, i) {
-
- /* We misuse getpgid as a check whether a
- * process still exists. */
- if (getpgid((pid_t) PTR_TO_ULONG(p)) >= 0)
- continue;
-
- if (errno != ESRCH)
- continue;
-
- set_remove(pids, p);
- }
-
- if (set_isempty(pids))
- return;
-
- n = now(CLOCK_MONOTONIC);
- if (n >= until)
- return;
-
- timespec_store(&ts, until - n);
- k = sigtimedwait(mask, NULL, &ts);
- if (k != SIGCHLD) {
-
- if (k < 0 && errno != EAGAIN) {
- log_error_errno(errno, "sigtimedwait() failed: %m");
- return;
- }
-
- if (k >= 0)
- log_warning("sigtimedwait() returned unexpected signal.");
- }
- }
-}
-
-static int killall(int sig, Set *pids, bool send_sighup) {
- _cleanup_closedir_ DIR *dir = NULL;
- struct dirent *d;
-
- dir = opendir("/proc");
- if (!dir)
- return -errno;
-
- while ((d = readdir(dir))) {
- pid_t pid;
-
- if (d->d_type != DT_DIR &&
- d->d_type != DT_UNKNOWN)
- continue;
-
- if (parse_pid(d->d_name, &pid) < 0)
- continue;
-
- if (ignore_proc(pid))
- continue;
-
- if (sig == SIGKILL) {
- _cleanup_free_ char *s = NULL;
-
- get_process_comm(pid, &s);
- log_notice("Sending SIGKILL to PID "PID_FMT" (%s).", pid, strna(s));
- }
-
- if (kill(pid, sig) >= 0) {
- if (pids)
- set_put(pids, ULONG_TO_PTR(pid));
- } else if (errno != ENOENT)
- log_warning_errno(errno, "Could not kill %d: %m", pid);
-
- if (send_sighup) {
- /* Optionally, also send a SIGHUP signal, but
- only if the process has a controlling
- tty. This is useful to allow handling of
- shells which ignore SIGTERM but react to
- SIGHUP. We do not send this to processes that
- have no controlling TTY since we don't want to
- trigger reloads of daemon processes. Also we
- make sure to only send this after SIGTERM so
- that SIGTERM is always first in the queue. */
-
-
- if (get_ctty_devnr(pid, NULL) >= 0)
- kill(pid, SIGHUP);
- }
- }
-
- return set_size(pids);
-}
-
-void broadcast_signal(int sig, bool wait_for_exit, bool send_sighup) {
- sigset_t mask, oldmask;
- _cleanup_set_free_ Set *pids = NULL;
-
- if (wait_for_exit)
- pids = set_new(NULL);
-
- assert_se(sigemptyset(&mask) == 0);
- assert_se(sigaddset(&mask, SIGCHLD) == 0);
- assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0);
-
- if (kill(-1, SIGSTOP) < 0 && errno != ESRCH)
- log_warning_errno(errno, "kill(-1, SIGSTOP) failed: %m");
-
- killall(sig, pids, send_sighup);
-
- if (kill(-1, SIGCONT) < 0 && errno != ESRCH)
- log_warning_errno(errno, "kill(-1, SIGCONT) failed: %m");
-
- if (wait_for_exit)
- wait_for_children(pids, &mask);
-
- assert_se(sigprocmask(SIG_SETMASK, &oldmask, NULL) == 0);
-}
~ianmdlvl / elogind.git / blobdiff