diff options
Diffstat (limited to 'lib/isc/win32/app.c')
| -rw-r--r-- | lib/isc/win32/app.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/lib/isc/win32/app.c b/lib/isc/win32/app.c new file mode 100644 index 0000000..b0db90d --- /dev/null +++ b/lib/isc/win32/app.c @@ -0,0 +1,260 @@ +/* + * Copyright (C) 2004, 2007 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 1999-2001 Internet Software Consortium. + * + * Permission to use, copy, modify, and/or 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 1.7 2007/06/19 23:47:19 tbox Exp $ */ + +#include <config.h> + +#include <sys/types.h> + +#include <stddef.h> +#include <stdlib.h> +#include <errno.h> +#include <unistd.h> +#include <process.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/string.h> +#include <isc/task.h> +#include <isc/time.h> +#include <isc/util.h> +#include <isc/thread.h> + +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; + +static isc_thread_t blockedthread; + +/* Events to wait for */ + +#define NUM_EVENTS 2 + +enum { + RELOAD_EVENT, + SHUTDOWN_EVENT +}; + +static HANDLE hEvents[NUM_EVENTS]; +DWORD dwWaitResult; + +/* + * We need to remember which thread is the main thread... + */ +static isc_thread_t main_thread; + +isc_result_t +isc_app_start(void) { + isc_result_t result; + + /* + * Start an ISC library application. + */ + + main_thread = GetCurrentThread(); + + result = isc_mutex_init(&lock); + if (result != ISC_R_SUCCESS) + return (result); + + /* Create the reload event in a non-signaled state */ + hEvents[RELOAD_EVENT] = CreateEvent(NULL, FALSE, FALSE, NULL); + + /* Create the shutdown event in a non-signaled state */ + hEvents[SHUTDOWN_EVENT] = CreateEvent(NULL, FALSE, FALSE, NULL); + + 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); +} + +isc_result_t +isc_app_run(void) { + isc_event_t *event, *next_event; + isc_task_t *task; + HANDLE *pHandles = NULL; + + REQUIRE(main_thread == GetCurrentThread()); + 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); + + /* + * There is no danger if isc_app_shutdown() is called before we wait + * for events. + */ + + while (!want_shutdown) { + dwWaitResult = WaitForMultipleObjects(NUM_EVENTS, hEvents, + FALSE, INFINITE); + + /* See why we returned */ + + if (WaitSucceeded(dwWaitResult, NUM_EVENTS)) { + /* + * The return was due to one of the events + * being signaled + */ + switch (WaitSucceededIndex(dwWaitResult)) { + case RELOAD_EVENT: + want_reload = ISC_TRUE; + break; + + case SHUTDOWN_EVENT: + want_shutdown = ISC_TRUE; + break; + } + } + if (want_reload) { + want_reload = ISC_FALSE; + return (ISC_R_RELOAD); + } + + if (want_shutdown && blocked) + exit(-1); + } + + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_app_shutdown(void) { + isc_boolean_t want_kill = ISC_TRUE; + + LOCK(&lock); + REQUIRE(running); + + if (shutdown_requested) + want_kill = ISC_FALSE; /* We're only signaling once */ + else + shutdown_requested = ISC_TRUE; + + UNLOCK(&lock); + if (want_kill) + SetEvent(hEvents[SHUTDOWN_EVENT]); + + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_app_reload(void) { + isc_boolean_t want_reload = ISC_TRUE; + + LOCK(&lock); + REQUIRE(running); + + /* + * Don't send the reload signal if we're shutting down. + */ + if (shutdown_requested) + want_reload = ISC_FALSE; + + UNLOCK(&lock); + if (want_reload) + SetEvent(hEvents[RELOAD_EVENT]); + + return (ISC_R_SUCCESS); +} + +void +isc_app_finish(void) { + DESTROYLOCK(&lock); +} + +void +isc_app_block(void) { + REQUIRE(running); + REQUIRE(!blocked); + + blocked = ISC_TRUE; + blockedthread = GetCurrentThread(); +} + +void +isc_app_unblock(void) { + REQUIRE(running); + REQUIRE(blocked); + blocked = ISC_FALSE; + REQUIRE(blockedthread == GetCurrentThread()); +} |