From 5a6aeddfa7262e41802c77f70c9ef88e9c2c2476 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sat, 26 May 2007 16:44:20 +0000 Subject: xpipe: introduce (saves ~170 bytes) udhcp/signalpipe.c: use pipe instead of socketpair. --- networking/udhcp/signalpipe.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'networking') diff --git a/networking/udhcp/signalpipe.c b/networking/udhcp/signalpipe.c index d52a931a9..9c7ead965 100644 --- a/networking/udhcp/signalpipe.c +++ b/networking/udhcp/signalpipe.c @@ -27,7 +27,8 @@ static int signal_pipe[2]; static void signal_handler(int sig) { - if (send(signal_pipe[1], &sig, sizeof(sig), MSG_DONTWAIT) < 0) + unsigned char ch = sig; /* use char, avoid dealing with partial writes */ + if (write(signal_pipe[1], &ch, 1) != 1) bb_perror_msg("cannot send signal"); } @@ -36,11 +37,11 @@ static void signal_handler(int sig) * and installs the signal handler */ void udhcp_sp_setup(void) { -// BTW, why socketpair and not just pipe? - if (socketpair(AF_UNIX, SOCK_STREAM, 0, signal_pipe)) - bb_perror_msg_and_die("socketpair"); + /* was socketpair, but it needs AF_UNIX in kernel */ + xpipe(signal_pipe); fcntl(signal_pipe[0], F_SETFD, FD_CLOEXEC); fcntl(signal_pipe[1], F_SETFD, FD_CLOEXEC); + fcntl(signal_pipe[1], F_SETFL, O_NONBLOCK); signal(SIGUSR1, signal_handler); signal(SIGUSR2, signal_handler); signal(SIGTERM, signal_handler); @@ -67,12 +68,12 @@ int udhcp_sp_fd_set(fd_set *rfds, int extra_fd) * your signal on success */ int udhcp_sp_read(fd_set *rfds) { - int sig; + unsigned char sig; if (!FD_ISSET(signal_pipe[0], rfds)) return 0; - if (read(signal_pipe[0], &sig, sizeof(sig)) < 0) + if (read(signal_pipe[0], &sig, 1) != 1) return -1; return sig; -- cgit v1.2.3