libfuse: fix fuse_remove_signal_handlers()

to properly restore the default signal handler.

Reported by: Chris Johnson <johnsocg@gmail.com>

diff --git a/ChangeLog b/ChangeLog
index b8ccda9760ddb70304289be43efd7446973cc198..279249390f9a745af0b2813db2ada45a12ae1a16 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-26  Miklos Szeredi <miklos@szeredi.hu>
+
+       * libfuse: fix fuse_remove_signal_handlers() to properly restore
+       the default signal handler.  Reported by: Chris Johnson
+
 2014-07-21  Miklos Szeredi <miklos@szeredi.hu>
 
        * libfuse: highlevel API: fix directory file handle passed to

diff --git a/lib/fuse_signals.c b/lib/fuse_signals.c
index 88ac39e187e019b463f962533225721b089ddd19..353cb24bd28419392a8d134bb54cad2067856aed 100644 (file)
--- a/lib/fuse_signals.c
+++ b/lib/fuse_signals.c
@@ -21,13 +21,13 @@ static void exit_handler(int sig)
                fuse_session_exit(fuse_instance);
 }
 
-static int set_one_signal_handler(int sig, void (*handler)(int))
+static int set_one_signal_handler(int sig, void (*handler)(int), int remove)
 {
        struct sigaction sa;
        struct sigaction old_sa;
 
        memset(&sa, 0, sizeof(struct sigaction));
-       sa.sa_handler = handler;
+       sa.sa_handler = remove ? SIG_DFL : handler;
        sigemptyset(&(sa.sa_mask));
        sa.sa_flags = 0;
 
@@ -36,7 +36,7 @@ static int set_one_signal_handler(int sig, void (*handler)(int))
                return -1;
        }
 
-       if (old_sa.sa_handler == SIG_DFL &&
+       if (old_sa.sa_handler == (remove ? handler : SIG_DFL) &&
            sigaction(sig, &sa, NULL) == -1) {
                perror("fuse: cannot set signal handler");
                return -1;
@@ -46,10 +46,10 @@ static int set_one_signal_handler(int sig, void (*handler)(int))
 
 int fuse_set_signal_handlers(struct fuse_session *se)
 {
-       if (set_one_signal_handler(SIGHUP, exit_handler) == -1 ||
-           set_one_signal_handler(SIGINT, exit_handler) == -1 ||
-           set_one_signal_handler(SIGTERM, exit_handler) == -1 ||
-           set_one_signal_handler(SIGPIPE, SIG_IGN) == -1)
+       if (set_one_signal_handler(SIGHUP, exit_handler, 0) == -1 ||
+           set_one_signal_handler(SIGINT, exit_handler, 0) == -1 ||
+           set_one_signal_handler(SIGTERM, exit_handler, 0) == -1 ||
+           set_one_signal_handler(SIGPIPE, SIG_IGN, 0) == -1)
                return -1;
 
        fuse_instance = se;
@@ -64,9 +64,9 @@ void fuse_remove_signal_handlers(struct fuse_session *se)
        else
                fuse_instance = NULL;
 
-       set_one_signal_handler(SIGHUP, SIG_DFL);
-       set_one_signal_handler(SIGINT, SIG_DFL);
-       set_one_signal_handler(SIGTERM, SIG_DFL);
-       set_one_signal_handler(SIGPIPE, SIG_DFL);
+       set_one_signal_handler(SIGHUP, exit_handler, 1);
+       set_one_signal_handler(SIGINT, exit_handler, 1);
+       set_one_signal_handler(SIGTERM, exit_handler, 1);
+       set_one_signal_handler(SIGPIPE, SIG_IGN, 1);
 }