add sigint.[ch]

git-svn-id: file:///home/lennart/svn/public/avahi/trunk@881 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe

2 files changed, 176 insertions, 0 deletions

diff --git a/avahi-utils/sigint.c b/avahi-utils/sigint.c
new file mode 100644
index 0000000..eb97f38
--- /dev/null
+++ b/avahi-utils/sigint.c
@@ -0,0 +1,146 @@
+/* $Id$ */
+
+/***
+  This file is part of avahi.
+ 
+  avahi 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.
+ 
+  avahi 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 avahi; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <unistd.h>
+#include <assert.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <stdio.h>
+
+#include <avahi-common/gccmacro.h>
+#include "sigint.h"
+
+static AvahiSimplePoll *simple_poll = NULL;
+static struct sigaction old_sigint_sa, old_sigterm_sa;
+static int pipe_fds[2] = { -1, -1 };
+static AvahiWatch *watch = NULL;
+
+static int set_nonblock(int fd) {
+    int n;
+    
+    assert(fd >= 0);
+
+    if ((n = fcntl(fd, F_GETFL)) < 0)
+        return -1;
+
+    if (n & O_NONBLOCK)
+        return 0;
+
+    return fcntl(fd, F_SETFL, n|O_NONBLOCK);
+}
+
+static void handler(int s) {
+    write(pipe_fds[1], &s, sizeof(s));
+}
+
+static void close_pipe_fds(void) {
+    if (pipe_fds[0] >= 0)
+        close(pipe_fds[0]);
+    if (pipe_fds[1] >= 0)
+        close(pipe_fds[1]);
+
+    pipe_fds[0] = pipe_fds[1] = -1;
+}
+
+static void watch_callback(AvahiWatch *w, int fd, AvahiWatchEvent event, AVAHI_GCC_UNUSED void *userdata) {
+    int s;
+    ssize_t l;
+    
+    assert(w);
+    assert(fd == pipe_fds[0]);
+    assert(event == AVAHI_WATCH_IN);
+
+    l = read(fd, &s, sizeof(s));
+    assert(l == sizeof(s));
+
+    fprintf(stderr, "Got %s, quitting.\n", s == SIGINT ? "SIGINT" : "SIGTERM");
+    avahi_simple_poll_quit(simple_poll);
+}
+
+int sigint_install(AvahiSimplePoll *spoll) {
+    struct sigaction sa;
+    const AvahiPoll *p;
+        
+    assert(spoll);
+    assert(!simple_poll);
+    assert(pipe_fds[0] == -1 && pipe_fds[1] == -1);
+
+    if (pipe(pipe_fds) < 0) {
+        fprintf(stderr, "pipe() failed: %s\n", strerror(errno));
+        return -1;
+    }
+
+    set_nonblock(pipe_fds[0]);
+    set_nonblock(pipe_fds[1]);
+
+    memset(&sa, 0, sizeof(sa));
+    sa.sa_handler = handler;
+    sa.sa_flags = SA_RESTART;
+
+    if (sigaction(SIGINT, &sa, &old_sigint_sa) < 0) {
+        fprintf(stderr, "sigaction() failed: %s\n", strerror(errno));
+        close_pipe_fds();
+        return -1;
+    }
+    
+    if (sigaction(SIGTERM, &sa, &old_sigterm_sa) < 0) {
+        sigaction(SIGINT, &old_sigint_sa, NULL);
+        fprintf(stderr, "sigaction() failed: %s\n", strerror(errno));
+        close_pipe_fds();
+        return -1;
+    }
+
+    p = avahi_simple_poll_get(spoll);
+    watch = p->watch_new(p, pipe_fds[0], AVAHI_WATCH_IN, watch_callback, NULL);
+    assert(watch);
+              
+    simple_poll = spoll;
+    return 0;
+}
+
+void sigint_uninstall(void) {
+    
+    if (!simple_poll)
+        return;
+
+    sigaction(SIGTERM, &old_sigterm_sa, NULL);
+    sigaction(SIGINT, &old_sigint_sa, NULL);
+
+    close_pipe_fds();
+
+    if (watch) {
+        const AvahiPoll *p;
+
+        assert(simple_poll);
+        p = avahi_simple_poll_get(simple_poll);
+
+        p->watch_free(watch);
+        watch = NULL;
+    }
+
+    simple_poll = NULL;
+}
diff --git a/avahi-utils/sigint.h b/avahi-utils/sigint.h
new file mode 100644
index 0000000..0bc5c34
--- /dev/null
+++ b/avahi-utils/sigint.h
@@ -0,0 +1,30 @@
+#ifndef foosigchfoo
+#define foosigchfoo
+
+/* $Id$ */
+
+/***
+  This file is part of avahi.
+ 
+  avahi 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.
+ 
+  avahi 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 avahi; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#include <avahi-common/simple-watch.h>
+
+int sigint_install(AvahiSimplePoll *spoll);
+void sigint_uninstall(void);
+
+#endif