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author | The Android Open Source Project <initial-contribution@android.com> | 2009-03-03 19:29:22 -0800 |
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committer | The Android Open Source Project <initial-contribution@android.com> | 2009-03-03 19:29:22 -0800 |
commit | f7c5421560640d23fc10803b9d59a9ff1d83e467 (patch) | |
tree | d6ae69d0d3f4a4d760a3254ec326bca4a8afacfe /signals.c | |
parent | d97c47cad830d00c9da685cc4ea157d6185f6c97 (diff) | |
download | external_dhcpcd-f7c5421560640d23fc10803b9d59a9ff1d83e467.zip external_dhcpcd-f7c5421560640d23fc10803b9d59a9ff1d83e467.tar.gz external_dhcpcd-f7c5421560640d23fc10803b9d59a9ff1d83e467.tar.bz2 |
auto import from //depot/cupcake/@135843
Diffstat (limited to 'signals.c')
-rw-r--r-- | signals.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/signals.c b/signals.c new file mode 100644 index 0000000..58679d6 --- /dev/null +++ b/signals.c @@ -0,0 +1,125 @@ +/* + * dhcpcd - DHCP client daemon + * Copyright 2006-2008 Roy Marples <roy@marples.name> + * All rights reserved + + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/types.h> +#include <sys/socket.h> + +#include <errno.h> +#include <signal.h> +#include <string.h> +#include <unistd.h> + +#include "common.h" +#include "signals.h" + +static int signal_pipe[2]; + +static const int handle_sigs[] = { + SIGHUP, + SIGALRM, + SIGTERM, + SIGINT +}; + +static void +signal_handler(int sig) +{ + int serrno = errno; + + write(signal_pipe[1], &sig, sizeof(sig)); + /* Restore errno */ + errno = serrno; +} + +int +signal_fd(void) +{ + return (signal_pipe[0]); +} + +/* Read a signal from the signal pipe. Returns 0 if there is + * no signal, -1 on error (and sets errno appropriately), and + * your signal on success */ +int +signal_read(void) +{ + int sig = -1; + char buf[16]; + size_t bytes; + + memset(buf, 0, sizeof(buf)); + bytes = read(signal_pipe[0], buf, sizeof(buf)); + if (bytes >= sizeof(sig)) + memcpy(&sig, buf, sizeof(sig)); + return sig; +} + +/* Call this before doing anything else. Sets up the socket pair + * and installs the signal handler */ +int +signal_init(void) +{ + if (pipe(signal_pipe) == -1) + return -1; + /* Don't block on read */ + if (set_nonblock(signal_pipe[0]) == -1) + return -1; + /* Stop any scripts from inheriting us */ + if (set_cloexec(signal_pipe[0]) == -1) + return -1; + if (set_cloexec(signal_pipe[1]) == -1) + return -1; + return 0; +} + +static int +signal_handle(void (*func)(int)) +{ + unsigned int i; + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = func; + sigemptyset(&sa.sa_mask); + + for (i = 0; i < sizeof(handle_sigs) / sizeof(handle_sigs[0]); i++) + if (sigaction(handle_sigs[i], &sa, NULL) == -1) + return -1; + return 0; +} + +int +signal_setup(void) +{ + return signal_handle(signal_handler); +} + +int +signal_reset(void) +{ + return signal_handle(SIG_DFL); +} |