diff options
Diffstat (limited to 'contrib/bind9/lib/isc/unix/app.c')
| -rw-r--r-- | contrib/bind9/lib/isc/unix/app.c | 683 |
1 files changed, 0 insertions, 683 deletions
diff --git a/contrib/bind9/lib/isc/unix/app.c b/contrib/bind9/lib/isc/unix/app.c deleted file mode 100644 index 59b1f6c..0000000 --- a/contrib/bind9/lib/isc/unix/app.c +++ /dev/null @@ -1,683 +0,0 @@ -/* - * Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC") - * Copyright (C) 1999-2003 Internet Software Consortium. - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE - * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - -/* $Id: app.c,v 1.50.18.2 2005/04/29 00:17:06 marka Exp $ */ - -/*! \file */ - -#include <config.h> - -#include <sys/param.h> /* Openserver 5.0.6A and FD_SETSIZE */ -#include <sys/types.h> - -#include <stddef.h> -#include <stdlib.h> -#include <errno.h> -#include <unistd.h> -#include <signal.h> -#include <sys/time.h> - -#include <isc/app.h> -#include <isc/boolean.h> -#include <isc/condition.h> -#include <isc/msgs.h> -#include <isc/mutex.h> -#include <isc/event.h> -#include <isc/platform.h> -#include <isc/strerror.h> -#include <isc/string.h> -#include <isc/task.h> -#include <isc/time.h> -#include <isc/util.h> - -#ifdef ISC_PLATFORM_USETHREADS -#include <pthread.h> -#else /* ISC_PLATFORM_USETHREADS */ -#include "../timer_p.h" -#include "../task_p.h" -#include "socket_p.h" -#endif /* ISC_PLATFORM_USETHREADS */ - -static isc_eventlist_t on_run; -static isc_mutex_t lock; -static isc_boolean_t shutdown_requested = ISC_FALSE; -static isc_boolean_t running = ISC_FALSE; -/*! - * We assume that 'want_shutdown' can be read and written atomically. - */ -static isc_boolean_t want_shutdown = ISC_FALSE; -/* - * We assume that 'want_reload' can be read and written atomically. - */ -static isc_boolean_t want_reload = ISC_FALSE; - -static isc_boolean_t blocked = ISC_FALSE; -#ifdef ISC_PLATFORM_USETHREADS -static pthread_t blockedthread; -#endif /* ISC_PLATFORM_USETHREADS */ - -#ifdef HAVE_LINUXTHREADS -/*! - * Linux has sigwait(), but it appears to prevent signal handlers from - * running, even if they're not in the set being waited for. This makes - * it impossible to get the default actions for SIGILL, SIGSEGV, etc. - * Instead of messing with it, we just use sigsuspend() instead. - */ -#undef HAVE_SIGWAIT -/*! - * We need to remember which thread is the main thread... - */ -static pthread_t main_thread; -#endif - -#ifndef HAVE_SIGWAIT -static void -exit_action(int arg) { - UNUSED(arg); - want_shutdown = ISC_TRUE; -} - -static void -reload_action(int arg) { - UNUSED(arg); - want_reload = ISC_TRUE; -} -#endif - -static isc_result_t -handle_signal(int sig, void (*handler)(int)) { - struct sigaction sa; - char strbuf[ISC_STRERRORSIZE]; - - memset(&sa, 0, sizeof(sa)); - sa.sa_handler = handler; - - if (sigfillset(&sa.sa_mask) != 0 || - sigaction(sig, &sa, NULL) < 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - isc_msgcat_get(isc_msgcat, ISC_MSGSET_APP, - ISC_MSG_SIGNALSETUP, - "handle_signal() %d setup: %s"), - sig, strbuf); - return (ISC_R_UNEXPECTED); - } - - return (ISC_R_SUCCESS); -} - -isc_result_t -isc_app_start(void) { - isc_result_t result; - int presult; - sigset_t sset; - char strbuf[ISC_STRERRORSIZE]; - - /* - * Start an ISC library application. - */ - -#ifdef NEED_PTHREAD_INIT - /* - * BSDI 3.1 seg faults in pthread_sigmask() if we don't do this. - */ - presult = pthread_init(); - if (presult != 0) { - isc__strerror(presult, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_start() pthread_init: %s", strbuf); - return (ISC_R_UNEXPECTED); - } -#endif - -#ifdef HAVE_LINUXTHREADS - main_thread = pthread_self(); -#endif - - result = isc_mutex_init(&lock); - if (result != ISC_R_SUCCESS) - return (result); - -#ifndef HAVE_SIGWAIT - /* - * Install do-nothing handlers for SIGINT and SIGTERM. - * - * We install them now because BSDI 3.1 won't block - * the default actions, regardless of what we do with - * pthread_sigmask(). - */ - result = handle_signal(SIGINT, exit_action); - if (result != ISC_R_SUCCESS) - return (result); - result = handle_signal(SIGTERM, exit_action); - if (result != ISC_R_SUCCESS) - return (result); -#endif - - /* - * Always ignore SIGPIPE. - */ - result = handle_signal(SIGPIPE, SIG_IGN); - if (result != ISC_R_SUCCESS) - return (result); - - /* - * On Solaris 2, delivery of a signal whose action is SIG_IGN - * will not cause sigwait() to return. We may have inherited - * unexpected actions for SIGHUP, SIGINT, and SIGTERM from our parent - * process (e.g, Solaris cron). Set an action of SIG_DFL to make - * sure sigwait() works as expected. Only do this for SIGTERM and - * SIGINT if we don't have sigwait(), since a different handler is - * installed above. - */ - result = handle_signal(SIGHUP, SIG_DFL); - if (result != ISC_R_SUCCESS) - return (result); - -#ifdef HAVE_SIGWAIT - result = handle_signal(SIGTERM, SIG_DFL); - if (result != ISC_R_SUCCESS) - return (result); - result = handle_signal(SIGINT, SIG_DFL); - if (result != ISC_R_SUCCESS) - return (result); -#endif - -#ifdef ISC_PLATFORM_USETHREADS - /* - * Block SIGHUP, SIGINT, SIGTERM. - * - * If isc_app_start() is called from the main thread before any other - * threads have been created, then the pthread_sigmask() call below - * will result in all threads having SIGHUP, SIGINT and SIGTERM - * blocked by default, ensuring that only the thread that calls - * sigwait() for them will get those signals. - */ - if (sigemptyset(&sset) != 0 || - sigaddset(&sset, SIGHUP) != 0 || - sigaddset(&sset, SIGINT) != 0 || - sigaddset(&sset, SIGTERM) != 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_start() sigsetops: %s", strbuf); - return (ISC_R_UNEXPECTED); - } - presult = pthread_sigmask(SIG_BLOCK, &sset, NULL); - if (presult != 0) { - isc__strerror(presult, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_start() pthread_sigmask: %s", - strbuf); - return (ISC_R_UNEXPECTED); - } -#else /* ISC_PLATFORM_USETHREADS */ - /* - * Unblock SIGHUP, SIGINT, SIGTERM. - * - * If we're not using threads, we need to make sure that SIGHUP, - * SIGINT and SIGTERM are not inherited as blocked from the parent - * process. - */ - if (sigemptyset(&sset) != 0 || - sigaddset(&sset, SIGHUP) != 0 || - sigaddset(&sset, SIGINT) != 0 || - sigaddset(&sset, SIGTERM) != 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_start() sigsetops: %s", strbuf); - return (ISC_R_UNEXPECTED); - } - presult = sigprocmask(SIG_UNBLOCK, &sset, NULL); - if (presult != 0) { - isc__strerror(presult, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_start() sigprocmask: %s", strbuf); - return (ISC_R_UNEXPECTED); - } -#endif /* ISC_PLATFORM_USETHREADS */ - - ISC_LIST_INIT(on_run); - - return (ISC_R_SUCCESS); -} - -isc_result_t -isc_app_onrun(isc_mem_t *mctx, isc_task_t *task, isc_taskaction_t action, - void *arg) -{ - isc_event_t *event; - isc_task_t *cloned_task = NULL; - isc_result_t result; - - LOCK(&lock); - - if (running) { - result = ISC_R_ALREADYRUNNING; - goto unlock; - } - - /* - * Note that we store the task to which we're going to send the event - * in the event's "sender" field. - */ - isc_task_attach(task, &cloned_task); - event = isc_event_allocate(mctx, cloned_task, ISC_APPEVENT_SHUTDOWN, - action, arg, sizeof(*event)); - if (event == NULL) { - result = ISC_R_NOMEMORY; - goto unlock; - } - - ISC_LIST_APPEND(on_run, event, ev_link); - - result = ISC_R_SUCCESS; - - unlock: - UNLOCK(&lock); - - return (result); -} - -#ifndef ISC_PLATFORM_USETHREADS -/*! - * Event loop for nonthreaded programs. - */ -static isc_result_t -evloop() { - isc_result_t result; - while (!want_shutdown) { - int n; - isc_time_t when, now; - struct timeval tv, *tvp; - fd_set readfds, writefds; - int maxfd; - isc_boolean_t readytasks; - isc_boolean_t call_timer_dispatch = ISC_FALSE; - - readytasks = isc__taskmgr_ready(); - if (readytasks) { - tv.tv_sec = 0; - tv.tv_usec = 0; - tvp = &tv; - call_timer_dispatch = ISC_TRUE; - } else { - result = isc__timermgr_nextevent(&when); - if (result != ISC_R_SUCCESS) - tvp = NULL; - else { - isc_uint64_t us; - - TIME_NOW(&now); - us = isc_time_microdiff(&when, &now); - if (us == 0) - call_timer_dispatch = ISC_TRUE; - tv.tv_sec = us / 1000000; - tv.tv_usec = us % 1000000; - tvp = &tv; - } - } - - isc__socketmgr_getfdsets(&readfds, &writefds, &maxfd); - n = select(maxfd, &readfds, &writefds, NULL, tvp); - - if (n == 0 || call_timer_dispatch) { - /* - * We call isc__timermgr_dispatch() only when - * necessary, in order to reduce overhead. If the - * select() call indicates a timeout, we need the - * dispatch. Even if not, if we set the 0-timeout - * for the select() call, we need to check the timer - * events. In the 'readytasks' case, there may be no - * timeout event actually, but there is no other way - * to reduce the overhead. - * Note that we do not have to worry about the case - * where a new timer is inserted during the select() - * call, since this loop only runs in the non-thread - * mode. - */ - isc__timermgr_dispatch(); - } - if (n > 0) - (void)isc__socketmgr_dispatch(&readfds, &writefds, - maxfd); - (void)isc__taskmgr_dispatch(); - - if (want_reload) { - want_reload = ISC_FALSE; - return (ISC_R_RELOAD); - } - } - return (ISC_R_SUCCESS); -} - -/* - * This is a gross hack to support waiting for condition - * variables in nonthreaded programs in a limited way; - * see lib/isc/nothreads/include/isc/condition.h. - * We implement isc_condition_wait() by entering the - * event loop recursively until the want_shutdown flag - * is set by isc_condition_signal(). - */ - -/*! - * \brief True if we are currently executing in the recursive - * event loop. - */ -static isc_boolean_t in_recursive_evloop = ISC_FALSE; - -/*! - * \brief True if we are exiting the event loop as the result of - * a call to isc_condition_signal() rather than a shutdown - * or reload. - */ -static isc_boolean_t signalled = ISC_FALSE; - -isc_result_t -isc__nothread_wait_hack(isc_condition_t *cp, isc_mutex_t *mp) { - isc_result_t result; - - UNUSED(cp); - UNUSED(mp); - - INSIST(!in_recursive_evloop); - in_recursive_evloop = ISC_TRUE; - - INSIST(*mp == 1); /* Mutex must be locked on entry. */ - --*mp; - - result = evloop(); - if (result == ISC_R_RELOAD) - want_reload = ISC_TRUE; - if (signalled) { - want_shutdown = ISC_FALSE; - signalled = ISC_FALSE; - } - - ++*mp; - in_recursive_evloop = ISC_FALSE; - return (ISC_R_SUCCESS); -} - -isc_result_t -isc__nothread_signal_hack(isc_condition_t *cp) { - - UNUSED(cp); - - INSIST(in_recursive_evloop); - - want_shutdown = ISC_TRUE; - signalled = ISC_TRUE; - return (ISC_R_SUCCESS); -} - -#endif /* ISC_PLATFORM_USETHREADS */ - -isc_result_t -isc_app_run(void) { - int result; - isc_event_t *event, *next_event; - isc_task_t *task; -#ifdef ISC_PLATFORM_USETHREADS - sigset_t sset; - char strbuf[ISC_STRERRORSIZE]; -#endif /* ISC_PLATFORM_USETHREADS */ -#ifdef HAVE_SIGWAIT - int sig; -#endif - -#ifdef HAVE_LINUXTHREADS - REQUIRE(main_thread == pthread_self()); -#endif - - LOCK(&lock); - - if (!running) { - running = ISC_TRUE; - - /* - * Post any on-run events (in FIFO order). - */ - for (event = ISC_LIST_HEAD(on_run); - event != NULL; - event = next_event) { - next_event = ISC_LIST_NEXT(event, ev_link); - ISC_LIST_UNLINK(on_run, event, ev_link); - task = event->ev_sender; - event->ev_sender = NULL; - isc_task_sendanddetach(&task, &event); - } - - } - - UNLOCK(&lock); - -#ifndef HAVE_SIGWAIT - /* - * Catch SIGHUP. - * - * We do this here to ensure that the signal handler is installed - * (i.e. that it wasn't a "one-shot" handler). - */ - result = handle_signal(SIGHUP, reload_action); - if (result != ISC_R_SUCCESS) - return (ISC_R_SUCCESS); -#endif - -#ifdef ISC_PLATFORM_USETHREADS - /* - * There is no danger if isc_app_shutdown() is called before we wait - * for signals. Signals are blocked, so any such signal will simply - * be made pending and we will get it when we call sigwait(). - */ - - while (!want_shutdown) { -#ifdef HAVE_SIGWAIT - /* - * Wait for SIGHUP, SIGINT, or SIGTERM. - */ - if (sigemptyset(&sset) != 0 || - sigaddset(&sset, SIGHUP) != 0 || - sigaddset(&sset, SIGINT) != 0 || - sigaddset(&sset, SIGTERM) != 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_run() sigsetops: %s", strbuf); - return (ISC_R_UNEXPECTED); - } - -#ifndef HAVE_UNIXWARE_SIGWAIT - result = sigwait(&sset, &sig); - if (result == 0) { - if (sig == SIGINT || - sig == SIGTERM) - want_shutdown = ISC_TRUE; - else if (sig == SIGHUP) - want_reload = ISC_TRUE; - } - -#else /* Using UnixWare sigwait semantics. */ - sig = sigwait(&sset); - if (sig >= 0) { - if (sig == SIGINT || - sig == SIGTERM) - want_shutdown = ISC_TRUE; - else if (sig == SIGHUP) - want_reload = ISC_TRUE; - } - -#endif /* HAVE_UNIXWARE_SIGWAIT */ -#else /* Don't have sigwait(). */ - /* - * Listen for all signals. - */ - if (sigemptyset(&sset) != 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_run() sigsetops: %s", strbuf); - return (ISC_R_UNEXPECTED); - } - result = sigsuspend(&sset); -#endif /* HAVE_SIGWAIT */ - - if (want_reload) { - want_reload = ISC_FALSE; - return (ISC_R_RELOAD); - } - - if (want_shutdown && blocked) - exit(1); - } - -#else /* ISC_PLATFORM_USETHREADS */ - - (void)isc__taskmgr_dispatch(); - - result = evloop(); - if (result != ISC_R_SUCCESS) - return (result); - -#endif /* ISC_PLATFORM_USETHREADS */ - - return (ISC_R_SUCCESS); -} - -isc_result_t -isc_app_shutdown(void) { - isc_boolean_t want_kill = ISC_TRUE; - char strbuf[ISC_STRERRORSIZE]; - - LOCK(&lock); - - REQUIRE(running); - - if (shutdown_requested) - want_kill = ISC_FALSE; - else - shutdown_requested = ISC_TRUE; - - UNLOCK(&lock); - - if (want_kill) { -#ifdef HAVE_LINUXTHREADS - int result; - - result = pthread_kill(main_thread, SIGTERM); - if (result != 0) { - isc__strerror(result, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_shutdown() pthread_kill: %s", - strbuf); - return (ISC_R_UNEXPECTED); - } -#else - if (kill(getpid(), SIGTERM) < 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_shutdown() kill: %s", strbuf); - return (ISC_R_UNEXPECTED); - } -#endif - } - - return (ISC_R_SUCCESS); -} - -isc_result_t -isc_app_reload(void) { - isc_boolean_t want_kill = ISC_TRUE; - char strbuf[ISC_STRERRORSIZE]; - - LOCK(&lock); - - REQUIRE(running); - - /* - * Don't send the reload signal if we're shutting down. - */ - if (shutdown_requested) - want_kill = ISC_FALSE; - - UNLOCK(&lock); - - if (want_kill) { -#ifdef HAVE_LINUXTHREADS - int result; - - result = pthread_kill(main_thread, SIGHUP); - if (result != 0) { - isc__strerror(result, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_reload() pthread_kill: %s", - strbuf); - return (ISC_R_UNEXPECTED); - } -#else - if (kill(getpid(), SIGHUP) < 0) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, - "isc_app_reload() kill: %s", strbuf); - return (ISC_R_UNEXPECTED); - } -#endif - } - - return (ISC_R_SUCCESS); -} - -void -isc_app_finish(void) { - DESTROYLOCK(&lock); -} - -void -isc_app_block(void) { -#ifdef ISC_PLATFORM_USETHREADS - sigset_t sset; -#endif /* ISC_PLATFORM_USETHREADS */ - REQUIRE(running); - REQUIRE(!blocked); - - blocked = ISC_TRUE; -#ifdef ISC_PLATFORM_USETHREADS - blockedthread = pthread_self(); - RUNTIME_CHECK(sigemptyset(&sset) == 0 && - sigaddset(&sset, SIGINT) == 0 && - sigaddset(&sset, SIGTERM) == 0); - RUNTIME_CHECK(pthread_sigmask(SIG_UNBLOCK, &sset, NULL) == 0); -#endif /* ISC_PLATFORM_USETHREADS */ -} - -void -isc_app_unblock(void) { -#ifdef ISC_PLATFORM_USETHREADS - sigset_t sset; -#endif /* ISC_PLATFORM_USETHREADS */ - - REQUIRE(running); - REQUIRE(blocked); - - blocked = ISC_FALSE; - -#ifdef ISC_PLATFORM_USETHREADS - REQUIRE(blockedthread == pthread_self()); - - RUNTIME_CHECK(sigemptyset(&sset) == 0 && - sigaddset(&sset, SIGINT) == 0 && - sigaddset(&sset, SIGTERM) == 0); - RUNTIME_CHECK(pthread_sigmask(SIG_BLOCK, &sset, NULL) == 0); -#endif /* ISC_PLATFORM_USETHREADS */ -} |
