diff options
| author | Denys Vlasenko <vda.linux@googlemail.com> | 2019-05-31 23:39:22 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2019-05-31 23:39:22 +0200 |
| commit | 65c34c52df3ed46f0b811d1858c271a373ab6af5 (patch) | |
| tree | 8c9a08f6ff1b442dbb642995d1870cb2efd87a0d /networking/udhcp/signalpipe.c | |
| parent | 91755cb16d496d1094f5d81051a1e1e6f27a21c1 (diff) | |
dhcp: get rid of static data signal_pipe
function old new delta
udhcp_sp_setup 65 110 +45
udhcp_sp_fd_set 60 59 -1
udhcpd_main 1442 1437 -5
udhcpc_main 2684 2679 -5
signal_pipe 8 - -8
packed_usage 33292 33284 -8
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/4 up/down: 45/-27) Total: 18 bytes
text data bss dec hex filename
952746 481 7296 960523 ea80b busybox_old
952768 481 7288 960537 ea819 busybox_unstripped
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'networking/udhcp/signalpipe.c')
| -rw-r--r-- | networking/udhcp/signalpipe.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/networking/udhcp/signalpipe.c b/networking/udhcp/signalpipe.c index 2ff78f0f2..81d1fc01a 100644 --- a/networking/udhcp/signalpipe.c +++ b/networking/udhcp/signalpipe.c @@ -20,14 +20,14 @@ */ #include "common.h" -/* Global variable: we access it from signal handler */ -static struct fd_pair signal_pipe; +#define READ_FD 3 +#define WRITE_FD 4 static void signal_handler(int sig) { int sv = errno; unsigned char ch = sig; /* use char, avoid dealing with partial writes */ - if (write(signal_pipe.wr, &ch, 1) != 1) + if (write(WRITE_FD, &ch, 1) != 1) bb_perror_msg("can't send signal"); errno = sv; } @@ -36,12 +36,25 @@ static void signal_handler(int sig) * and installs the signal handler */ void FAST_FUNC udhcp_sp_setup(void) { + struct fd_pair signal_pipe; + + /* All callers also want this, so... */ + bb_sanitize_stdio(); + /* was socketpair, but it needs AF_UNIX in kernel */ xpiped_pair(signal_pipe); - close_on_exec_on(signal_pipe.rd); - close_on_exec_on(signal_pipe.wr); - ndelay_on(signal_pipe.rd); - ndelay_on(signal_pipe.wr); + + /* usually we get fds 3 and 4, but if we get higher ones... */ + if (signal_pipe.rd != READ_FD) + xmove_fd(signal_pipe.rd, READ_FD); + if (signal_pipe.wr != WRITE_FD) + xmove_fd(signal_pipe.wr, WRITE_FD); + + close_on_exec_on(READ_FD); + close_on_exec_on(WRITE_FD); + ndelay_on(READ_FD); + ndelay_on(WRITE_FD); + bb_signals(0 + (1 << SIGUSR1) + (1 << SIGUSR2) @@ -54,7 +67,7 @@ void FAST_FUNC udhcp_sp_setup(void) */ void FAST_FUNC udhcp_sp_fd_set(struct pollfd pfds[2], int extra_fd) { - pfds[0].fd = signal_pipe.rd; + pfds[0].fd = READ_FD; pfds[0].events = POLLIN; pfds[1].fd = -1; if (extra_fd >= 0) { @@ -74,7 +87,7 @@ int FAST_FUNC udhcp_sp_read(void) unsigned char sig; /* Can't block here, fd is in nonblocking mode */ - if (safe_read(signal_pipe.rd, &sig, 1) != 1) + if (safe_read(READ_FD, &sig, 1) != 1) return 0; return sig; |