/contrib/ntp/libntp/iosignal.c
https://bitbucket.org/freebsd/freebsd-head/ · C · 557 lines · 412 code · 70 blank · 75 comment · 111 complexity · 8c3815570d7d245b6475afa4c67e7145 MD5 · raw file
- /*
- * iosignal.c - input/output routines for ntpd. The socket-opening code
- * was shamelessly stolen from ntpd.
- */
- /*
- * [Bug 158]
- * Do the #includes differently, as under some versions of Linux
- * sys/param.h has a #undef CONFIG_PHONE line in it.
- *
- * As we have ~40 CONFIG_ variables, I don't feel like renaming them
- * every time somebody adds a new macro to some system header.
- */
- #ifdef HAVE_CONFIG_H
- # include <config.h>
- #endif
- #include <stdio.h>
- #include <signal.h>
- #ifdef HAVE_SYS_PARAM_H
- # include <sys/param.h>
- #endif /* HAVE_SYS_PARAM_H */
- #ifdef HAVE_SYS_IOCTL_H
- # include <sys/ioctl.h>
- #endif
- #include <arpa/inet.h>
- #if _BSDI_VERSION >= 199510
- # include <ifaddrs.h>
- #endif
- # ifdef __QNXNTO__
- # include <fcntl.h>
- # include <unix.h>
- # define FNDELAY O_NDELAY
- # endif
- #include "ntp_machine.h"
- #include "ntpd.h"
- #include "ntp_io.h"
- #include "ntp_if.h"
- #include "ntp_stdlib.h"
- #include "iosignal.h"
- #if defined(HAVE_SIGNALED_IO)
- static int sigio_block_count = 0;
- # if defined(HAVE_SIGACTION)
- /*
- * If sigaction() is used for signal handling and a signal is
- * pending then the kernel blocks the signal before it calls
- * the signal handler.
- *
- * The variable below is used to take care that the SIGIO signal
- * is not unintentionally unblocked inside the sigio_handler()
- * if the handler executes a piece of code that is normally
- * bracketed by BLOCKIO()/UNBLOCKIO() calls.
- */
- static int sigio_handler_active = 0;
- # endif
- extern void input_handler P((l_fp *));
- /*
- * SIGPOLL and SIGIO ROUTINES.
- */
- /*
- * Some systems (MOST) define SIGPOLL == SIGIO, others SIGIO == SIGPOLL, and
- * a few have separate SIGIO and SIGPOLL signals. This code checks for the
- * SIGIO == SIGPOLL case at compile time.
- * Do not define USE_SIGPOLL or USE_SIGIO.
- * these are interal only to iosignal.c!
- */
- # if defined(USE_SIGPOLL)
- # undef USE_SIGPOLL
- # endif
- # if defined(USE_SIGIO)
- # undef USE_SIGIO
- # endif
- # if defined(USE_TTY_SIGPOLL) || defined(USE_UDP_SIGPOLL)
- # define USE_SIGPOLL
- # endif
- # if !defined(USE_TTY_SIGPOLL) || !defined(USE_UDP_SIGPOLL)
- # define USE_SIGIO
- # endif
- # if defined(USE_SIGIO) && defined(USE_SIGPOLL)
- # if SIGIO == SIGPOLL
- # define USE_SIGIO
- # undef USE_SIGPOLL
- # endif /* SIGIO == SIGPOLL */
- # endif /* USE_SIGIO && USE_SIGIO */
- /*
- * TTY initialization routines.
- */
- int
- init_clock_sig(
- struct refclockio *rio
- )
- {
- # ifdef USE_TTY_SIGPOLL
- {
- /* DO NOT ATTEMPT TO MAKE CLOCK-FD A CTTY: not portable, unreliable */
- if (ioctl(rio->fd, I_SETSIG, S_INPUT) < 0)
- {
- msyslog(LOG_ERR,
- "init_clock_sig: ioctl(I_SETSIG, S_INPUT) failed: %m");
- return 1;
- }
- return 0;
- }
- # else
- /*
- * Special cases first!
- */
- /* Was: defined(SYS_HPUX) */
- # if defined(FIOSSAIOOWN) && defined(FIOSNBIO) && defined(FIOSSAIOSTAT)
- #define CLOCK_DONE
- {
- int pgrp, on = 1;
- /* DO NOT ATTEMPT TO MAKE CLOCK-FD A CTTY: not portable, unreliable */
- pgrp = getpid();
- if (ioctl(rio->fd, FIOSSAIOOWN, (char *)&pgrp) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOSSAIOOWN) fails for clock I/O: %m");
- exit(1);
- /*NOTREACHED*/
- }
- /*
- * set non-blocking, async I/O on the descriptor
- */
- if (ioctl(rio->fd, FIOSNBIO, (char *)&on) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOSNBIO) fails for clock I/O: %m");
- exit(1);
- /*NOTREACHED*/
- }
- if (ioctl(rio->fd, FIOSSAIOSTAT, (char *)&on) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOSSAIOSTAT) fails for clock I/O: %m");
- exit(1);
- /*NOTREACHED*/
- }
- return 0;
- }
- # endif /* SYS_HPUX: FIOSSAIOOWN && FIOSNBIO && FIOSSAIOSTAT */
- /* Was: defined(SYS_AIX) && !defined(_BSD) */
- # if !defined(_BSD) && defined(_AIX) && defined(FIOASYNC) && defined(FIOSETOWN)
- /*
- * SYSV compatibility mode under AIX.
- */
- #define CLOCK_DONE
- {
- int pgrp, on = 1;
- /* DO NOT ATTEMPT TO MAKE CLOCK-FD A CTTY: not portable, unreliable */
- if (ioctl(rio->fd, FIOASYNC, (char *)&on) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOASYNC) fails for clock I/O: %m");
- return 1;
- }
- pgrp = -getpid();
- if (ioctl(rio->fd, FIOSETOWN, (char*)&pgrp) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOSETOWN) fails for clock I/O: %m");
- return 1;
- }
- if (fcntl(rio->fd, F_SETFL, FNDELAY|FASYNC) < 0)
- {
- msyslog(LOG_ERR, "fcntl(FNDELAY|FASYNC) fails for clock I/O: %m");
- return 1;
- }
- return 0;
- }
- # endif /* AIX && !BSD: !_BSD && FIOASYNC && FIOSETOWN */
- # ifndef CLOCK_DONE
- {
- /* DO NOT ATTEMPT TO MAKE CLOCK-FD A CTTY: not portable, unreliable */
- # if defined(TIOCSCTTY) && defined(USE_FSETOWNCTTY)
- /*
- * there are, however, always exceptions to the rules
- * one is, that OSF accepts SETOWN on TTY fd's only, iff they are
- * CTTYs. SunOS and HPUX do not semm to have this restriction.
- * another question is: how can you do multiple SIGIO from several
- * ttys (as they all should be CTTYs), wondering...
- *
- * kd 95-07-16
- */
- if (ioctl(rio->fd, TIOCSCTTY, 0) == -1)
- {
- msyslog(LOG_ERR, "ioctl(TIOCSCTTY, 0) fails for clock I/O: %m");
- return 1;
- }
- # endif /* TIOCSCTTY && USE_FSETOWNCTTY */
- if (fcntl(rio->fd, F_SETOWN, getpid()) == -1)
- {
- msyslog(LOG_ERR, "fcntl(F_SETOWN) fails for clock I/O: %m");
- return 1;
- }
- if (fcntl(rio->fd, F_SETFL, FNDELAY|FASYNC) < 0)
- {
- msyslog(LOG_ERR,
- "fcntl(FNDELAY|FASYNC) fails for clock I/O: %m");
- return 1;
- }
- return 0;
- }
- # endif /* CLOCK_DONE */
- # endif /* !USE_TTY_SIGPOLL */
- }
- void
- init_socket_sig(
- int fd
- )
- {
- # ifdef USE_UDP_SIGPOLL
- {
- if (ioctl(fd, I_SETSIG, S_INPUT) < 0)
- {
- msyslog(LOG_ERR,
- "init_socket_sig: ioctl(I_SETSIG, S_INPUT) failed: %m");
- exit(1);
- }
- }
- # else /* USE_UDP_SIGPOLL */
- {
- int pgrp;
- # ifdef FIOASYNC
- int on = 1;
- # endif
- # if defined(FIOASYNC)
- if (ioctl(fd, FIOASYNC, (char *)&on) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOASYNC) fails: %m");
- exit(1);
- /*NOTREACHED*/
- }
- # elif defined(FASYNC)
- {
- int flags;
- if ((flags = fcntl(fd, F_GETFL, 0)) == -1)
- {
- msyslog(LOG_ERR, "fcntl(F_GETFL) fails: %m");
- exit(1);
- /*NOTREACHED*/
- }
- if (fcntl(fd, F_SETFL, flags|FASYNC) < 0)
- {
- msyslog(LOG_ERR, "fcntl(...|FASYNC) fails: %m");
- exit(1);
- /*NOTREACHED*/
- }
- }
- # else
- # include "Bletch: Need asynchronous I/O!"
- # endif
- # ifdef UDP_BACKWARDS_SETOWN
- pgrp = -getpid();
- # else
- pgrp = getpid();
- # endif
- # if defined(SIOCSPGRP)
- if (ioctl(fd, SIOCSPGRP, (char *)&pgrp) == -1)
- {
- msyslog(LOG_ERR, "ioctl(SIOCSPGRP) fails: %m");
- exit(1);
- /*NOTREACHED*/
- }
- # elif defined(FIOSETOWN)
- if (ioctl(fd, FIOSETOWN, (char*)&pgrp) == -1)
- {
- msyslog(LOG_ERR, "ioctl(FIOSETOWN) fails: %m");
- exit(1);
- /*NOTREACHED*/
- }
- # elif defined(F_SETOWN)
- if (fcntl(fd, F_SETOWN, pgrp) == -1)
- {
- msyslog(LOG_ERR, "fcntl(F_SETOWN) fails: %m");
- exit(1);
- /*NOTREACHED*/
- }
- # else
- # include "Bletch: Need to set process(group) to receive SIG(IO|POLL)"
- # endif
- }
- # endif /* USE_UDP_SIGPOLL */
- }
- RETSIGTYPE
- sigio_handler(
- int sig
- )
- {
- int saved_errno = errno;
- l_fp ts;
- get_systime(&ts);
- # if defined(HAVE_SIGACTION)
- sigio_handler_active++;
- if (sigio_handler_active != 1) /* This should never happen! */
- msyslog(LOG_ERR, "sigio_handler: sigio_handler_active != 1");
- # endif
- (void)input_handler(&ts);
- # if defined(HAVE_SIGACTION)
- sigio_handler_active--;
- if (sigio_handler_active != 0) /* This should never happen! */
- msyslog(LOG_ERR, "sigio_handler: sigio_handler_active != 0");
- # endif
- errno = saved_errno;
- }
- /*
- * Signal support routines.
- */
- # ifdef HAVE_SIGACTION
- void
- set_signal(void)
- {
- # ifdef USE_SIGIO
- (void) signal_no_reset(SIGIO, sigio_handler);
- # endif
- # ifdef USE_SIGPOLL
- (void) signal_no_reset(SIGPOLL, sigio_handler);
- # endif
- }
- void
- block_io_and_alarm(void)
- {
- sigset_t set;
- if (sigemptyset(&set))
- msyslog(LOG_ERR, "block_io_and_alarm: sigemptyset() failed: %m");
- # if defined(USE_SIGIO)
- if (sigaddset(&set, SIGIO))
- msyslog(LOG_ERR, "block_io_and_alarm: sigaddset(SIGIO) failed: %m");
- # endif
- # if defined(USE_SIGPOLL)
- if (sigaddset(&set, SIGPOLL))
- msyslog(LOG_ERR, "block_io_and_alarm: sigaddset(SIGPOLL) failed: %m");
- # endif
- if (sigaddset(&set, SIGALRM))
- msyslog(LOG_ERR, "block_io_and_alarm: sigaddset(SIGALRM) failed: %m");
- if (sigprocmask(SIG_BLOCK, &set, NULL))
- msyslog(LOG_ERR, "block_io_and_alarm: sigprocmask() failed: %m");
- }
- void
- block_sigio(void)
- {
- if ( sigio_handler_active == 0 ) /* not called from within signal handler */
- {
- sigset_t set;
- ++sigio_block_count;
- if (sigio_block_count > 1)
- msyslog(LOG_INFO, "block_sigio: sigio_block_count > 1");
- if (sigio_block_count < 1)
- msyslog(LOG_INFO, "block_sigio: sigio_block_count < 1");
- if (sigemptyset(&set))
- msyslog(LOG_ERR, "block_sigio: sigemptyset() failed: %m");
- # if defined(USE_SIGIO)
- if (sigaddset(&set, SIGIO))
- msyslog(LOG_ERR, "block_sigio: sigaddset(SIGIO) failed: %m");
- # endif
- # if defined(USE_SIGPOLL)
- if (sigaddset(&set, SIGPOLL))
- msyslog(LOG_ERR, "block_sigio: sigaddset(SIGPOLL) failed: %m");
- # endif
- if (sigprocmask(SIG_BLOCK, &set, NULL))
- msyslog(LOG_ERR, "block_sigio: sigprocmask() failed: %m");
- }
- }
- void
- unblock_io_and_alarm(void)
- {
- sigset_t unset;
- if (sigemptyset(&unset))
- msyslog(LOG_ERR, "unblock_io_and_alarm: sigemptyset() failed: %m");
- # if defined(USE_SIGIO)
- if (sigaddset(&unset, SIGIO))
- msyslog(LOG_ERR, "unblock_io_and_alarm: sigaddset(SIGIO) failed: %m");
- # endif
- # if defined(USE_SIGPOLL)
- if (sigaddset(&unset, SIGPOLL))
- msyslog(LOG_ERR, "unblock_io_and_alarm: sigaddset(SIGPOLL) failed: %m");
- # endif
- if (sigaddset(&unset, SIGALRM))
- msyslog(LOG_ERR, "unblock_io_and_alarm: sigaddset(SIGALRM) failed: %m");
- if (sigprocmask(SIG_UNBLOCK, &unset, NULL))
- msyslog(LOG_ERR, "unblock_io_and_alarm: sigprocmask() failed: %m");
- }
- void
- unblock_sigio(void)
- {
- if ( sigio_handler_active == 0 ) /* not called from within signal handler */
- {
- sigset_t unset;
- --sigio_block_count;
- if (sigio_block_count > 0)
- msyslog(LOG_INFO, "unblock_sigio: sigio_block_count > 0");
- if (sigio_block_count < 0)
- msyslog(LOG_INFO, "unblock_sigio: sigio_block_count < 0");
- if (sigemptyset(&unset))
- msyslog(LOG_ERR, "unblock_sigio: sigemptyset() failed: %m");
- # if defined(USE_SIGIO)
- if (sigaddset(&unset, SIGIO))
- msyslog(LOG_ERR, "unblock_sigio: sigaddset(SIGIO) failed: %m");
- # endif
- # if defined(USE_SIGPOLL)
- if (sigaddset(&unset, SIGPOLL))
- msyslog(LOG_ERR, "unblock_sigio: sigaddset(SIGPOLL) failed: %m");
- # endif
- if (sigprocmask(SIG_UNBLOCK, &unset, NULL))
- msyslog(LOG_ERR, "unblock_sigio: sigprocmask() failed: %m");
- }
- }
- void
- wait_for_signal(void)
- {
- sigset_t old;
- if (sigprocmask(SIG_UNBLOCK, NULL, &old))
- msyslog(LOG_ERR, "wait_for_signal: sigprocmask() failed: %m");
- # if defined(USE_SIGIO)
- if (sigdelset(&old, SIGIO))
- msyslog(LOG_ERR, "wait_for_signal: sigdelset(SIGIO) failed: %m");
- # endif
- # if defined(USE_SIGPOLL)
- if (sigdelset(&old, SIGPOLL))
- msyslog(LOG_ERR, "wait_for_signal: sigdelset(SIGPOLL) failed: %m");
- # endif
- if (sigdelset(&old, SIGALRM))
- msyslog(LOG_ERR, "wait_for_signal: sigdelset(SIGALRM) failed: %m");
- if (sigsuspend(&old) && (errno != EINTR))
- msyslog(LOG_ERR, "wait_for_signal: sigsuspend() failed: %m");
- }
- # else /* !HAVE_SIGACTION */
- /*
- * Must be an old bsd system.
- * We assume there is no SIGPOLL.
- */
- void
- block_io_and_alarm(void)
- {
- int mask;
- mask = sigmask(SIGIO) | sigmask(SIGALRM);
- if (sigblock(mask))
- msyslog(LOG_ERR, "block_io_and_alarm: sigblock() failed: %m");
- }
- void
- block_sigio(void)
- {
- int mask;
- ++sigio_block_count;
- if (sigio_block_count > 1)
- msyslog(LOG_INFO, "block_sigio: sigio_block_count > 1");
- if (sigio_block_count < 1)
- msyslog(LOG_INFO, "block_sigio: sigio_block_count < 1");
- mask = sigmask(SIGIO);
- if (sigblock(mask))
- msyslog(LOG_ERR, "block_sigio: sigblock() failed: %m");
- }
- void
- set_signal(void)
- {
- (void) signal_no_reset(SIGIO, sigio_handler);
- }
- void
- unblock_io_and_alarm(void)
- {
- int mask, omask;
- mask = sigmask(SIGIO) | sigmask(SIGALRM);
- omask = sigblock(0);
- omask &= ~mask;
- (void) sigsetmask(omask);
- }
- void
- unblock_sigio(void)
- {
- int mask, omask;
- --sigio_block_count;
- if (sigio_block_count > 0)
- msyslog(LOG_INFO, "unblock_sigio: sigio_block_count > 0");
- if (sigio_block_count < 0)
- msyslog(LOG_INFO, "unblock_sigio: sigio_block_count < 0");
- mask = sigmask(SIGIO);
- omask = sigblock(0);
- omask &= ~mask;
- (void) sigsetmask(omask);
- }
- void
- wait_for_signal(void)
- {
- int mask, omask;
- mask = sigmask(SIGIO) | sigmask(SIGALRM);
- omask = sigblock(0);
- omask &= ~mask;
- if (sigpause(omask) && (errno != EINTR))
- msyslog(LOG_ERR, "wait_for_signal: sigspause() failed: %m");
- }
- # endif /* HAVE_SIGACTION */
- #else
- int NotAnEmptyCompilationUnit;
- #endif