diff options
Diffstat (limited to 'threads.c')
| -rw-r--r-- | threads.c | 122 |
1 files changed, 78 insertions, 44 deletions
@@ -5,7 +5,7 @@ * * File begun on 2007-12-14 by RGerhards * - * Copyright 2007 Rainer Gerhards and Adiscon GmbH. + * Copyright 2007, 2009 Rainer Gerhards and Adiscon GmbH. * * This file is part of rsyslog. * @@ -29,6 +29,7 @@ #include <stdlib.h> #include <string.h> #include <signal.h> +#include <errno.h> #include <pthread.h> #include <assert.h> @@ -36,6 +37,7 @@ #include "dirty.h" #include "linkedlist.h" #include "threads.h" +#include "srUtils.h" /* linked list of currently-known threads */ static linkedList_t llThrds; @@ -44,23 +46,20 @@ static linkedList_t llThrds; /* Construct a new thread object */ -static rsRetVal thrdConstruct(thrdInfo_t **ppThis) +static rsRetVal +thrdConstruct(thrdInfo_t **ppThis) { DEFiRet; thrdInfo_t *pThis; assert(ppThis != NULL); - if((pThis = calloc(1, sizeof(thrdInfo_t))) == NULL) - return RS_RET_OUT_OF_MEMORY; - - /* OK, we got the element, now initialize members that should - * not be zero-filled. - */ - pThis->mutTermOK = (pthread_mutex_t *) malloc (sizeof (pthread_mutex_t)); - pthread_mutex_init (pThis->mutTermOK, NULL); - + CHKmalloc(pThis = calloc(1, sizeof(thrdInfo_t))); + pthread_mutex_init(&pThis->mutThrd, NULL); + pthread_cond_init(&pThis->condThrdTerm, NULL); *ppThis = pThis; + +finalize_it: RETiRet; } @@ -77,13 +76,54 @@ static rsRetVal thrdDestruct(thrdInfo_t *pThis) if(pThis->bIsActive == 1) { thrdTerminate(pThis); } - free(pThis->mutTermOK); + pthread_mutex_destroy(&pThis->mutThrd); + pthread_cond_destroy(&pThis->condThrdTerm); free(pThis); RETiRet; } +/* terminate a thread via the non-cancel interface + * This is a separate function as it involves a bit more of code. + * rgerhads, 2009-10-15 + */ +static inline rsRetVal +thrdTerminateNonCancel(thrdInfo_t *pThis) +{ + struct timespec tTimeout; + int ret; + DEFiRet; + assert(pThis != NULL); + + DBGPRINTF("request term via SIGTTIN for input thread 0x%x\n", (unsigned) pThis->thrdID); + pThis->bShallStop = TRUE; + do { + d_pthread_mutex_lock(&pThis->mutThrd); + pthread_kill(pThis->thrdID, SIGTTIN); + timeoutComp(&tTimeout, 10); /* a fixed 10ms timeout, do after lock (may take long!) */ + ret = d_pthread_cond_timedwait(&pThis->condThrdTerm, &pThis->mutThrd, &tTimeout); + d_pthread_mutex_unlock(&pThis->mutThrd); + if(Debug) { + if(ret == ETIMEDOUT) { + dbgprintf("input thread term: had a timeout waiting on thread termination\n"); + } else if(ret == 0) { + dbgprintf("input thread term: thread returned normally and is terminated\n"); + } else { + char errStr[1024]; + int err = errno; + rs_strerror_r(err, errStr, sizeof(errStr)); + dbgprintf("input thread term: cond_wait returned with error %d: %s\n", + err, errStr); + } + } + } while(pThis->bIsActive); + DBGPRINTF("non-cancel input thread termination succeeded for thread 0x%x\n", (unsigned) pThis->thrdID); + + RETiRet; +} + + /* terminate a thread gracefully. */ rsRetVal thrdTerminate(thrdInfo_t *pThis) @@ -91,9 +131,14 @@ rsRetVal thrdTerminate(thrdInfo_t *pThis) DEFiRet; assert(pThis != NULL); - pthread_cancel(pThis->thrdID); - pthread_join(pThis->thrdID, NULL); /* wait for cancel to complete */ - pThis->bIsActive = 0; + if(pThis->bNeedsCancel) { + DBGPRINTF("request term via canceling for input thread 0x%x\n", (unsigned) pThis->thrdID); + pthread_cancel(pThis->thrdID); + pThis->bIsActive = 0; + } else { + thrdTerminateNonCancel(pThis); + } + pthread_join(pThis->thrdID, NULL); /* wait for input thread to complete */ /* call cleanup function, if any */ if(pThis->pAfterRun != NULL) @@ -132,6 +177,11 @@ static void* thrdStarter(void *arg) sigfillset(&sigSet); pthread_sigmask(SIG_BLOCK, &sigSet, NULL); + /* but ignore SIGTTN, which we (ab)use to signal the thread to shutdown -- rgerhards, 2009-07-20 */ + sigemptyset(&sigSet); + sigaddset(&sigSet, SIGTTIN); + pthread_sigmask(SIG_UNBLOCK, &sigSet, NULL); + /* setup complete, we are now ready to execute the user code. We will not * regain control until the user code is finished, in which case we terminate * the thread. @@ -139,6 +189,16 @@ static void* thrdStarter(void *arg) iRet = pThis->pUsrThrdMain(pThis); dbgprintf("thrdStarter: usrThrdMain 0x%lx returned with iRet %d, exiting now.\n", (unsigned long) pThis->thrdID, iRet); + + /* signal master control that we exit (we do the mutex lock mostly to + * keep the thread debugger happer, it would not really be necessary with + * the logic we employ...) + */ + pThis->bIsActive = 0; + d_pthread_mutex_lock(&pThis->mutThrd); + pthread_cond_signal(&pThis->condThrdTerm); + d_pthread_mutex_unlock(&pThis->mutThrd); + ENDfunc pthread_exit(0); } @@ -147,7 +207,7 @@ static void* thrdStarter(void *arg) * executing threads. It is added at the end of the list. * rgerhards, 2007-12-14 */ -rsRetVal thrdCreate(rsRetVal (*thrdMain)(thrdInfo_t*), rsRetVal(*afterRun)(thrdInfo_t *)) +rsRetVal thrdCreate(rsRetVal (*thrdMain)(thrdInfo_t*), rsRetVal(*afterRun)(thrdInfo_t *), sbool bNeedsCancel) { DEFiRet; thrdInfo_t *pThis; @@ -158,6 +218,7 @@ rsRetVal thrdCreate(rsRetVal (*thrdMain)(thrdInfo_t*), rsRetVal(*afterRun)(thrdI pThis->bIsActive = 1; pThis->pUsrThrdMain = thrdMain; pThis->pAfterRun = afterRun; + pThis->bNeedsCancel = bNeedsCancel; pthread_create(&pThis->thrdID, NULL, thrdStarter, pThis); CHKiRet(llAppend(&llThrds, NULL, pThis)); @@ -183,37 +244,10 @@ rsRetVal thrdInit(void) rsRetVal thrdExit(void) { DEFiRet; - iRet = llDestroy(&llThrds); - - RETiRet; -} - - -/* thrdSleep() - a fairly portable way to put a thread to sleep. It - * will wake up when - * a) the wake-time is over - * b) the thread shall be terminated - * Returns RS_RET_OK if all went well, RS_RET_TERMINATE_NOW if the calling - * thread shall be terminated and any other state if an error happened. - * rgerhards, 2007-12-17 - */ -rsRetVal -thrdSleep(thrdInfo_t *pThis, int iSeconds, int iuSeconds) -{ - DEFiRet; - struct timeval tvSelectTimeout; - - assert(pThis != NULL); - tvSelectTimeout.tv_sec = iSeconds; - tvSelectTimeout.tv_usec = iuSeconds; /* micro seconds */ - select(1, NULL, NULL, NULL, &tvSelectTimeout); - if(pThis->bShallStop) - iRet = RS_RET_TERMINATE_NOW; RETiRet; } -/* - * vi:set ai: +/* vi:set ai: */ |