release/src/router/ntfs-3g/libfuse-lite/fuse_signals.c

   1 /*
   2     FUSE: Filesystem in Userspace
   3     Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
   4
   5     This program can be distributed under the terms of the GNU LGPLv2.
   6     See the file COPYING.LIB
   7 */
   8
   9 #include "config.h"
  10 #include "fuse_lowlevel.h"
  11
  12 #include <stdio.h>
  13 #include <string.h>
  14 #include <signal.h>
  15
  16 static struct fuse_session *fuse_instance;
  17
  18 static void exit_handler(int sig)
  19 {
  20     (void) sig;
  21     if (fuse_instance)
  22         fuse_session_exit(fuse_instance);
  23 }
  24
  25 static int set_one_signal_handler(int sig, void (*handler)(int))
  26 {
  27     struct sigaction sa;
  28     struct sigaction old_sa;
  29
  30     memset(&sa, 0, sizeof(struct sigaction));
  31     sa.sa_handler = handler;
  32     sigemptyset(&(sa.sa_mask));
  33     sa.sa_flags = 0;
  34
  35     if (sigaction(sig, NULL, &old_sa) == -1) {
  36         perror("fuse: cannot get old signal handler");
  37         return -1;
  38     }
  39
  40     if (old_sa.sa_handler == SIG_DFL &&
  41         sigaction(sig, &sa, NULL) == -1) {
  42         perror("fuse: cannot set signal handler");
  43         return -1;
  44     }
  45     return 0;
  46 }
  47
  48 int fuse_set_signal_handlers(struct fuse_session *se)
  49 {
  50     if (set_one_signal_handler(SIGHUP, exit_handler) == -1 ||
  51         set_one_signal_handler(SIGINT, exit_handler) == -1 ||
  52         set_one_signal_handler(SIGTERM, exit_handler) == -1 ||
  53         set_one_signal_handler(SIGPIPE, SIG_IGN) == -1)
  54         return -1;
  55
  56     fuse_instance = se;
  57     return 0;
  58 }
  59
  60 void fuse_remove_signal_handlers(struct fuse_session *se)
  61 {
  62     if (fuse_instance != se)
  63         fprintf(stderr,
  64                 "fuse: fuse_remove_signal_handlers: unknown session\n");
  65     else
  66         fuse_instance = NULL;
  67
  68     set_one_signal_handler(SIGHUP, SIG_DFL);
  69     set_one_signal_handler(SIGINT, SIG_DFL);
  70     set_one_signal_handler(SIGTERM, SIG_DFL);
  71     set_one_signal_handler(SIGPIPE, SIG_DFL);
  72 }
  73