rpmio/rpmsq.c

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00001 
00005 #include "system.h"
00006 
00007 #if defined(__LCLINT__)
00008 #define _BITS_SIGTHREAD_H       /* XXX avoid __sigset_t heartburn. */
00009 
00010 /*@-incondefs -protoparammatch@*/
00011 /*@-exportheader@*/
00012 /*@constant int SA_SIGINFO@*/
00013 extern int sighold(int sig)
00014         /*@globals errno, systemState @*/;
00015 extern int sigignore(int sig)
00016         /*@globals errno, systemState @*/;
00017 extern int sigpause(int sig)
00018         /*@globals errno, systemState @*/;
00019 extern int sigrelse(int sig)
00020         /*@globals errno, systemState @*/;
00021 extern void (*sigset(int sig, void (*disp)(int)))(int)
00022         /*@globals errno, systemState @*/;
00023 
00024 struct qelem;
00025 extern  void insque(struct qelem * __elem, struct qelem * __prev)
00026         /*@modifies  __elem, __prev @*/;
00027 extern  void remque(struct qelem * __elem)
00028         /*@modifies  __elem @*/;
00029 
00030 extern pthread_t pthread_self(void)
00031         /*@*/;
00032 extern int pthread_equal(pthread_t t1, pthread_t t2)
00033         /*@*/;
00034 
00035 extern int pthread_create(/*@out@*/ pthread_t *restrict thread,
00036                 const pthread_attr_t *restrict attr,
00037                 void *(*start_routine)(void*), void *restrict arg)
00038         /*@modifies *thread @*/;
00039 extern int pthread_join(pthread_t thread, /*@out@*/ void **value_ptr)
00040         /*@modifies *value_ptr @*/;
00041 
00042 extern int pthread_setcancelstate(int state, /*@out@*/ int *oldstate)
00043         /*@globals internalState @*/
00044         /*@modifies *oldstate, internalState @*/;
00045 extern int pthread_setcanceltype(int type, /*@out@*/ int *oldtype)
00046         /*@globals internalState @*/
00047         /*@modifies *oldtype, internalState @*/;
00048 extern void pthread_testcancel(void)
00049         /*@globals internalState @*/
00050         /*@modifies internalState @*/;
00051 extern void pthread_cleanup_pop(int execute)
00052         /*@globals internalState @*/
00053         /*@modifies internalState @*/;
00054 extern void pthread_cleanup_push(void (*routine)(void*), void *arg)
00055         /*@globals internalState @*/
00056         /*@modifies internalState @*/;
00057 extern void _pthread_cleanup_pop(/*@out@*/ struct _pthread_cleanup_buffer *__buffer, int execute)
00058         /*@globals internalState @*/
00059         /*@modifies internalState @*/;
00060 extern void _pthread_cleanup_push(/*@out@*/ struct _pthread_cleanup_buffer *__buffer, void (*routine)(void*), /*@out@*/ void *arg)
00061         /*@globals internalState @*/
00062         /*@modifies internalState @*/;
00063 
00064 extern int pthread_mutexattr_destroy(pthread_mutexattr_t *attr)
00065         /*@globals errno, internalState @*/
00066         /*@modifies *attr, errno, internalState @*/;
00067 extern int pthread_mutexattr_init(/*@out@*/ pthread_mutexattr_t *attr)
00068         /*@globals errno, internalState @*/
00069         /*@modifies *attr, errno, internalState @*/;
00070 
00071 int pthread_mutexattr_gettype(const pthread_mutexattr_t *restrict attr,
00072                 /*@out@*/ int *restrict type)
00073         /*@modifies *type @*/;
00074 int pthread_mutexattr_settype(pthread_mutexattr_t *attr, int type)
00075         /*@globals errno, internalState @*/
00076         /*@modifies *attr, errno, internalState @*/;
00077 
00078 extern int pthread_mutex_destroy(pthread_mutex_t *mutex)
00079         /*@modifies *mutex @*/;
00080 extern int pthread_mutex_init(/*@out@*/ pthread_mutex_t *restrict mutex,
00081                 /*@null@*/ const pthread_mutexattr_t *restrict attr)
00082         /*@globals errno, internalState @*/
00083         /*@modifies *mutex, errno, internalState @*/;
00084 
00085 extern int pthread_mutex_lock(pthread_mutex_t *mutex)
00086         /*@globals errno @*/
00087         /*@modifies *mutex, errno @*/;
00088 extern int pthread_mutex_trylock(pthread_mutex_t *mutex)
00089         /*@globals errno @*/
00090         /*@modifies *mutex, errno @*/;
00091 extern int pthread_mutex_unlock(pthread_mutex_t *mutex)
00092         /*@globals errno @*/
00093         /*@modifies *mutex, errno @*/;
00094 
00095 extern int pthread_cond_destroy(pthread_cond_t *cond)
00096         /*@modifies *cond @*/;
00097 extern int pthread_cond_init(/*@out@*/ pthread_cond_t *restrict cond,
00098                 const pthread_condattr_t *restrict attr)
00099         /*@globals errno, internalState @*/
00100         /*@modifies *cond, errno, internalState @*/;
00101 
00102 extern int pthread_cond_timedwait(pthread_cond_t *restrict cond,
00103                 pthread_mutex_t *restrict mutex,
00104                 const struct timespec *restrict abstime)
00105         /*@modifies *cond, *mutex @*/;
00106 extern int pthread_cond_wait(pthread_cond_t *restrict cond,
00107                 pthread_mutex_t *restrict mutex)
00108         /*@modifies *cond, *mutex @*/;
00109 extern int pthread_cond_broadcast(pthread_cond_t *cond)
00110         /*@globals errno, internalState @*/
00111         /*@modifies *cond, errno, internalState @*/;
00112 extern int pthread_cond_signal(pthread_cond_t *cond)
00113         /*@globals errno, internalState @*/
00114         /*@modifies *cond, errno, internalState @*/;
00115 
00116 /*@=exportheader@*/
00117 /*@=incondefs =protoparammatch@*/
00118 #endif
00119 
00120 #include <signal.h>
00121 #include <sys/signal.h>
00122 #include <sys/wait.h>
00123 #include <search.h>
00124 
00125 #if defined(HAVE_PTHREAD_H)
00126 
00127 #include <pthread.h>
00128 
00129 /* XXX suggested in bugzilla #159024 */
00130 #if PTHREAD_MUTEX_DEFAULT != PTHREAD_MUTEX_NORMAL
00131   #error RPM expects PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_NORMAL
00132 #endif
00133 
00134 #ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
00135 /*@unchecked@*/
00136 static pthread_mutex_t rpmsigTbl_lock = PTHREAD_MUTEX_INITIALIZER;
00137 #else
00138 /*@unchecked@*/
00139 /*@-type@*/
00140 static pthread_mutex_t rpmsigTbl_lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
00141 /*@=type@*/
00142 #endif
00143 
00144 #define DO_LOCK()       pthread_mutex_lock(&rpmsigTbl_lock);
00145 #define DO_UNLOCK()     pthread_mutex_unlock(&rpmsigTbl_lock);
00146 #define INIT_LOCK()     \
00147     {   pthread_mutexattr_t attr; \
00148         (void) pthread_mutexattr_init(&attr); \
00149         (void) pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); \
00150         (void) pthread_mutex_init (&rpmsigTbl_lock, &attr); \
00151         (void) pthread_mutexattr_destroy(&attr); \
00152         rpmsigTbl_sigchld->active = 0; \
00153     }
00154 #define ADD_REF(__tbl)  (__tbl)->active++
00155 #define SUB_REF(__tbl)  --(__tbl)->active
00156 #define CLEANUP_HANDLER(__handler, __arg, __oldtypeptr) \
00157     (void) pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, (__oldtypeptr));\
00158         pthread_cleanup_push((__handler), (__arg));
00159 #define CLEANUP_RESET(__execute, __oldtype) \
00160     pthread_cleanup_pop(__execute); \
00161     (void) pthread_setcanceltype ((__oldtype), &(__oldtype));
00162 
00163 #define SAME_THREAD(_a, _b)     pthread_equal(((pthread_t)_a), ((pthread_t)_b))
00164 
00165 #define ME()    ((void *)pthread_self())
00166 
00167 #else
00168 
00169 #define DO_LOCK()
00170 #define DO_UNLOCK()
00171 #define INIT_LOCK()
00172 #define ADD_REF(__tbl)  /*@-noeffect@*/ (0) /*@=noeffect@*/
00173 #define SUB_REF(__tbl)  /*@-noeffect@*/ (0) /*@=noeffect@*/
00174 #define CLEANUP_HANDLER(__handler, __arg, __oldtypeptr)
00175 #define CLEANUP_RESET(__execute, __oldtype)
00176 
00177 #define SAME_THREAD(_a, _b)     (42)
00178 
00179 #define ME()    (((void *)getpid()))
00180 
00181 #endif  /* HAVE_PTHREAD_H */
00182 
00183 #include <rpmsq.h>
00184 
00185 #include "debug.h"
00186 
00187 #define _RPMSQ_DEBUG    0
00188 /*@unchecked@*/
00189 int _rpmsq_debug = _RPMSQ_DEBUG;
00190 
00191 /*@unchecked@*/
00192 static struct rpmsqElem rpmsqRock;
00193 
00194 /*@-compmempass@*/
00195 /*@unchecked@*/
00196 rpmsq rpmsqQueue = &rpmsqRock;
00197 /*@=compmempass@*/
00198 
00199 int rpmsqInsert(void * elem, void * prev)
00200 {
00201     rpmsq sq = (rpmsq) elem;
00202     int ret = -1;
00203 
00204     if (sq != NULL) {
00205 #ifdef _RPMSQ_DEBUG
00206 if (_rpmsq_debug)
00207 fprintf(stderr, "    Insert(%p): %p\n", ME(), sq);
00208 #endif
00209         ret = sighold(SIGCHLD);
00210         if (ret == 0) {
00211             sq->child = 0;
00212             sq->reaped = 0;
00213             sq->status = 0;
00214             sq->reaper = 1;
00215 /*@-bounds@*/
00216             sq->pipes[0] = sq->pipes[1] = -1;
00217 /*@=bounds@*/
00218 
00219             sq->id = ME();
00220             ret = pthread_mutex_init(&sq->mutex, NULL);
00221             insque(elem, (prev != NULL ? prev : rpmsqQueue));
00222             ret = sigrelse(SIGCHLD);
00223         }
00224     }
00225     return ret;
00226 }
00227 
00228 int rpmsqRemove(void * elem)
00229 {
00230     rpmsq sq = (rpmsq) elem;
00231     int ret = -1;
00232 
00233     if (elem != NULL) {
00234 
00235 #ifdef _RPMSQ_DEBUG
00236 if (_rpmsq_debug)
00237 fprintf(stderr, "    Remove(%p): %p\n", ME(), sq);
00238 #endif
00239         ret = sighold (SIGCHLD);
00240         if (ret == 0) {
00241             remque(elem);
00242            
00243             /* Unlock the mutex and then destroy it */ 
00244             if((ret = pthread_mutex_unlock(&sq->mutex)) == 0)
00245                 ret = pthread_mutex_destroy(&sq->mutex);
00246 
00247             sq->id = NULL;
00248 /*@-bounds@*/
00249             if (sq->pipes[1])   ret = close(sq->pipes[1]);
00250             if (sq->pipes[0])   ret = close(sq->pipes[0]);
00251             sq->pipes[0] = sq->pipes[1] = -1;
00252 /*@=bounds@*/
00253 #ifdef  NOTYET  /* rpmpsmWait debugging message needs */
00254             sq->reaper = 1;
00255             sq->status = 0;
00256             sq->reaped = 0;
00257             sq->child = 0;
00258 #endif
00259             ret = sigrelse(SIGCHLD);
00260         }
00261     }
00262     return ret;
00263 }
00264 
00265 /*@unchecked@*/
00266 sigset_t rpmsqCaught;
00267 
00268 /*@unchecked@*/
00269 /*@-fullinitblock@*/
00270 static struct rpmsig_s {
00271     int signum;
00272     void (*handler) (int signum, void * info, void * context);
00273     int active;
00274     struct sigaction oact;
00275 } rpmsigTbl[] = {
00276     { SIGINT,   rpmsqAction },
00277 #define rpmsigTbl_sigint        (&rpmsigTbl[0])
00278     { SIGQUIT,  rpmsqAction },
00279 #define rpmsigTbl_sigquit       (&rpmsigTbl[1])
00280     { SIGCHLD,  rpmsqAction },
00281 #define rpmsigTbl_sigchld       (&rpmsigTbl[2])
00282     { SIGHUP,   rpmsqAction },
00283 #define rpmsigTbl_sighup        (&rpmsigTbl[3])
00284     { SIGTERM,  rpmsqAction },
00285 #define rpmsigTbl_sigterm       (&rpmsigTbl[4])
00286     { SIGPIPE,  rpmsqAction },
00287 #define rpmsigTbl_sigpipe       (&rpmsigTbl[5])
00288     { -1,       NULL },
00289 };
00290 /*@=fullinitblock@*/
00291 
00292 void rpmsqAction(int signum,
00293                 /*@unused@*/ void * info, /*@unused@*/ void * context)
00294 {
00295     int save = errno;
00296     rpmsig tbl;
00297 
00298     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00299         if (tbl->signum != signum)
00300             continue;
00301 
00302         (void) sigaddset(&rpmsqCaught, signum);
00303 
00304         switch (signum) {
00305         case SIGCHLD:
00306             while (1) {
00307                 rpmsq sq;
00308                 int status = 0;
00309                 pid_t reaped = waitpid(0, &status, WNOHANG);
00310 
00311                 /* XXX errno set to ECHILD/EINVAL/EINTR. */
00312                 if (reaped <= 0)
00313                     /*@innerbreak@*/ break;
00314 
00315                 /* XXX insque(3)/remque(3) are dequeue, not ring. */
00316                 for (sq = rpmsqQueue->q_forw;
00317                      sq != NULL && sq != rpmsqQueue;
00318                      sq = sq->q_forw)
00319                 {
00320                     int ret;
00321 
00322                     if (sq->child != reaped)
00323                         /*@innercontinue@*/ continue;
00324                     sq->reaped = reaped;
00325                     sq->status = status;
00326 
00327                     /* Unlock the mutex.  The waiter will then be able to 
00328                      * aquire the lock.  
00329                      *
00330                      * XXX: jbj, wtd, if this fails? 
00331                      */
00332                     ret = pthread_mutex_unlock(&sq->mutex); 
00333 
00334                     /*@innerbreak@*/ break;
00335                 }
00336             }
00337             /*@switchbreak@*/ break;
00338         default:
00339             /*@switchbreak@*/ break;
00340         }
00341         break;
00342     }
00343     errno = save;
00344 }
00345 
00346 int rpmsqEnable(int signum, /*@null@*/ rpmsqAction_t handler)
00347         /*@globals rpmsigTbl @*/
00348         /*@modifies rpmsigTbl @*/
00349 {
00350     int tblsignum = (signum >= 0 ? signum : -signum);
00351     struct sigaction sa;
00352     rpmsig tbl;
00353     int ret = -1;
00354 
00355     (void) DO_LOCK ();
00356     if (rpmsqQueue->id == NULL)
00357         rpmsqQueue->id = ME();
00358     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00359         if (tblsignum != tbl->signum)
00360             continue;
00361 
00362         if (signum >= 0) {                      /* Enable. */
00363             if (ADD_REF(tbl) <= 0) {
00364                 (void) sigdelset(&rpmsqCaught, tbl->signum);
00365 
00366                 /* XXX Don't set a signal handler if already SIG_IGN */
00367                 (void) sigaction(tbl->signum, NULL, &tbl->oact);
00368                 if (tbl->oact.sa_handler == SIG_IGN)
00369                     continue;
00370 
00371                 (void) sigemptyset (&sa.sa_mask);
00372                 sa.sa_flags = SA_SIGINFO;
00373 #if defined(__LCLINT__) /* XXX glibc has union to track handler prototype. */
00374                 sa.sa_handler = (handler != NULL ? handler : tbl->handler);
00375 #else
00376                 sa.sa_sigaction = (handler != NULL ? handler : tbl->handler);
00377 #endif
00378                 if (sigaction(tbl->signum, &sa, &tbl->oact) < 0) {
00379                     SUB_REF(tbl);
00380                     break;
00381                 }
00382                 tbl->active = 1;                /* XXX just in case */
00383                 if (handler != NULL)
00384                     tbl->handler = handler;
00385             }
00386         } else {                                /* Disable. */
00387             if (SUB_REF(tbl) <= 0) {
00388                 if (sigaction(tbl->signum, &tbl->oact, NULL) < 0)
00389                     break;
00390                 tbl->active = 0;                /* XXX just in case */
00391                 tbl->handler = (handler != NULL ? handler : rpmsqAction);
00392             }
00393         }
00394         ret = tbl->active;
00395         break;
00396     }
00397     (void) DO_UNLOCK ();
00398     return ret;
00399 }
00400 
00401 pid_t rpmsqFork(rpmsq sq)
00402 {
00403     pid_t pid;
00404     int xx;
00405     int nothreads = 0;   /* XXX: Shouldn't this be a global? */
00406 
00407     if (sq->reaper) {
00408         xx = rpmsqInsert(sq, NULL);
00409 #ifdef _RPMSQ_DEBUG
00410 if (_rpmsq_debug)
00411 fprintf(stderr, "    Enable(%p): %p\n", ME(), sq);
00412 #endif
00413         xx = rpmsqEnable(SIGCHLD, NULL);
00414     }
00415 
00416     xx = pipe(sq->pipes);
00417 
00418     xx = sighold(SIGCHLD);
00419 
00420     /* 
00421      * Initialize the cond var mutex.   We have to aquire the lock we 
00422      * use for the condition before we fork.  Otherwise it is possible for
00423      * the child to exit, we get sigchild and the sig handler to send 
00424      * the condition signal before we are waiting on the condition.
00425      */
00426     if (!nothreads) {
00427         if(pthread_mutex_lock(&sq->mutex)) {
00428             /* Yack we did not get the lock, lets just give up */
00429 /*@-bounds@*/
00430             xx = close(sq->pipes[0]);
00431             xx = close(sq->pipes[1]);
00432             sq->pipes[0] = sq->pipes[1] = -1;
00433 /*@=bounds@*/
00434             goto out;
00435         }
00436     }
00437 
00438     pid = fork();
00439     if (pid < (pid_t) 0) {              /* fork failed.  */
00440         sq->child = (pid_t)-1;
00441 /*@-bounds@*/
00442         xx = close(sq->pipes[0]);
00443         xx = close(sq->pipes[1]);
00444         sq->pipes[0] = sq->pipes[1] = -1;
00445 /*@=bounds@*/
00446         goto out;
00447     } else if (pid == (pid_t) 0) {      /* Child. */
00448         int yy;
00449 
00450         /* Block to permit parent time to wait. */
00451 /*@-bounds@*/
00452         xx = close(sq->pipes[1]);
00453         xx = read(sq->pipes[0], &yy, sizeof(yy));
00454         xx = close(sq->pipes[0]);
00455         sq->pipes[0] = sq->pipes[1] = -1;
00456 /*@=bounds@*/
00457 
00458 #ifdef _RPMSQ_DEBUG
00459 if (_rpmsq_debug)
00460 fprintf(stderr, "     Child(%p): %p child %d\n", ME(), sq, getpid());
00461 #endif
00462 
00463     } else {                            /* Parent. */
00464 
00465         sq->child = pid;
00466 
00467 #ifdef _RPMSQ_DEBUG
00468 if (_rpmsq_debug)
00469 fprintf(stderr, "    Parent(%p): %p child %d\n", ME(), sq, sq->child);
00470 #endif
00471 
00472     }
00473 
00474 out:
00475     xx = sigrelse(SIGCHLD);
00476     return sq->child;
00477 }
00478 
00485 static int rpmsqWaitUnregister(rpmsq sq)
00486         /*@globals fileSystem, internalState @*/
00487         /*@modifies sq, fileSystem, internalState @*/
00488 {
00489     int nothreads = 0;
00490     int ret = 0;
00491     int xx;
00492 
00493     /* Protect sq->reaped from handler changes. */
00494     ret = sighold(SIGCHLD);
00495 
00496     /* Start the child, linux often runs child before parent. */
00497 /*@-bounds@*/
00498     if (sq->pipes[0] >= 0)
00499         xx = close(sq->pipes[0]);
00500     if (sq->pipes[1] >= 0)
00501         xx = close(sq->pipes[1]);
00502     sq->pipes[0] = sq->pipes[1] = -1;
00503 /*@=bounds@*/
00504 
00505     /* Put a stopwatch on the time spent waiting to measure performance gain. */
00506     (void) rpmswEnter(&sq->op, -1);
00507 
00508     /* Wait for handler to receive SIGCHLD. */
00509     /*@-infloops@*/
00510     while (ret == 0 && sq->reaped != sq->child) {
00511         if (nothreads)
00512             /* Note that sigpause re-enables SIGCHLD. */
00513             ret = sigpause(SIGCHLD);
00514         else {
00515             xx = sigrelse(SIGCHLD);
00516             
00517             /* 
00518              * We start before the fork with this mutex locked;
00519              * The only one that unlocks this the signal handler.
00520              * So if we get the lock the child has been reaped.
00521              */
00522             ret = pthread_mutex_lock(&sq->mutex);
00523             xx = sighold(SIGCHLD);
00524         }
00525     }
00526     /*@=infloops@*/
00527 
00528     /* Accumulate stopwatch time spent waiting, potential performance gain. */
00529     sq->ms_scriptlets += rpmswExit(&sq->op, -1)/1000;
00530 
00531     xx = sigrelse(SIGCHLD);
00532 
00533 #ifdef _RPMSQ_DEBUG
00534 if (_rpmsq_debug)
00535 fprintf(stderr, "      Wake(%p): %p child %d reaper %d ret %d\n", ME(), sq, sq->child, sq->reaper, ret);
00536 #endif
00537 
00538     /* Remove processed SIGCHLD item from queue. */
00539     xx = rpmsqRemove(sq);
00540 
00541     /* Disable SIGCHLD handler on refcount == 0. */
00542     xx = rpmsqEnable(-SIGCHLD, NULL);
00543 #ifdef _RPMSQ_DEBUG
00544 if (_rpmsq_debug)
00545 fprintf(stderr, "   Disable(%p): %p\n", ME(), sq);
00546 #endif
00547 
00548     return ret;
00549 }
00550 
00551 pid_t rpmsqWait(rpmsq sq)
00552 {
00553 
00554 #ifdef _RPMSQ_DEBUG
00555 if (_rpmsq_debug)
00556 fprintf(stderr, "      Wait(%p): %p child %d reaper %d\n", ME(), sq, sq->child, sq->reaper);
00557 #endif
00558 
00559     if (sq->reaper) {
00560         (void) rpmsqWaitUnregister(sq);
00561     } else {
00562         pid_t reaped;
00563         int status;
00564         do {
00565             reaped = waitpid(sq->child, &status, 0);
00566         } while (reaped >= 0 && reaped != sq->child);
00567         sq->reaped = reaped;
00568         sq->status = status;
00569 #ifdef _RPMSQ_DEBUG
00570 if (_rpmsq_debug)
00571 fprintf(stderr, "   Waitpid(%p): %p child %d reaped %d\n", ME(), sq, sq->child, sq->reaped);
00572 #endif
00573     }
00574 
00575 #ifdef _RPMSQ_DEBUG
00576 if (_rpmsq_debug)
00577 fprintf(stderr, "      Fini(%p): %p child %d status 0x%x\n", ME(), sq, sq->child, sq->status);
00578 #endif
00579 
00580     return sq->reaped;
00581 }
00582 
00583 void * rpmsqThread(void * (*start) (void * arg), void * arg)
00584 {
00585     pthread_t pth;
00586     int ret;
00587 
00588     ret = pthread_create(&pth, NULL, start, arg);
00589     return (ret == 0 ? (void *)pth : NULL);
00590 }
00591 
00592 int rpmsqJoin(void * thread)
00593 {
00594     pthread_t pth = (pthread_t) thread;
00595     if (thread == NULL)
00596         return EINVAL;
00597     return pthread_join(pth, NULL);
00598 }
00599 
00600 int rpmsqThreadEqual(void * thread)
00601 {
00602     pthread_t t1 = (pthread_t) thread;
00603     pthread_t t2 = pthread_self();
00604     return pthread_equal(t1, t2);
00605 }
00606 
00610 static void
00611 sigchld_cancel (void *arg)
00612         /*@globals rpmsigTbl, fileSystem, internalState @*/
00613         /*@modifies rpmsigTbl, fileSystem, internalState @*/
00614 {
00615     pid_t child = *(pid_t *) arg;
00616     pid_t result;
00617 
00618     (void) kill(child, SIGKILL);
00619 
00620     do {
00621         result = waitpid(child, NULL, 0);
00622     } while (result == (pid_t)-1 && errno == EINTR);
00623 
00624     (void) DO_LOCK ();
00625     if (SUB_REF (rpmsigTbl_sigchld) == 0) {
00626         (void) rpmsqEnable(-SIGQUIT, NULL);
00627         (void) rpmsqEnable(-SIGINT, NULL);
00628     }
00629     (void) DO_UNLOCK ();
00630 }
00631 
00635 int
00636 rpmsqExecve (const char ** argv)
00637         /*@globals rpmsigTbl @*/
00638         /*@modifies rpmsigTbl @*/
00639 {
00640     int oldtype;
00641     int status = -1;
00642     pid_t pid = 0;
00643     pid_t result;
00644     sigset_t newMask, oldMask;
00645     rpmsq sq = memset(alloca(sizeof(*sq)), 0, sizeof(*sq));
00646 
00647 #ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
00648         INIT_LOCK ();
00649 #endif
00650 
00651     (void) DO_LOCK ();
00652     if (ADD_REF (rpmsigTbl_sigchld) == 0) {
00653         if (rpmsqEnable(SIGINT, NULL) < 0) {
00654             SUB_REF (rpmsigTbl_sigchld);
00655             goto out;
00656         }
00657         if (rpmsqEnable(SIGQUIT, NULL) < 0) {
00658             SUB_REF (rpmsigTbl_sigchld);
00659             goto out_restore_sigint;
00660         }
00661     }
00662     (void) DO_UNLOCK ();
00663 
00664     (void) sigemptyset (&newMask);
00665     (void) sigaddset (&newMask, SIGCHLD);
00666     if (sigprocmask (SIG_BLOCK, &newMask, &oldMask) < 0) {
00667         (void) DO_LOCK ();
00668         if (SUB_REF (rpmsigTbl_sigchld) == 0)
00669             goto out_restore_sigquit_and_sigint;
00670         goto out;
00671     }
00672 
00673     CLEANUP_HANDLER(sigchld_cancel, &pid, &oldtype);
00674 
00675     pid = fork ();
00676     if (pid < (pid_t) 0) {              /* fork failed.  */
00677         goto out;
00678     } else if (pid == (pid_t) 0) {      /* Child. */
00679 
00680         /* Restore the signals.  */
00681         (void) sigaction (SIGINT, &rpmsigTbl_sigint->oact, NULL);
00682         (void) sigaction (SIGQUIT, &rpmsigTbl_sigquit->oact, NULL);
00683         (void) sigprocmask (SIG_SETMASK, &oldMask, NULL);
00684 
00685         /* Reset rpmsigTbl lock and refcnt. */
00686         INIT_LOCK ();
00687 
00688         (void) execve (argv[0], (char *const *) argv, environ);
00689         _exit (127);
00690     } else {                            /* Parent. */
00691         do {
00692             result = waitpid(pid, &status, 0);
00693         } while (result == (pid_t)-1 && errno == EINTR);
00694         if (result != pid)
00695             status = -1;
00696     }
00697 
00698     CLEANUP_RESET(0, oldtype);
00699 
00700     (void) DO_LOCK ();
00701     if ((SUB_REF (rpmsigTbl_sigchld) == 0 &&
00702         (rpmsqEnable(-SIGINT, NULL) < 0 || rpmsqEnable (-SIGQUIT, NULL) < 0))
00703       || sigprocmask (SIG_SETMASK, &oldMask, NULL) != 0)
00704     {
00705         status = -1;
00706     }
00707     goto out;
00708 
00709 out_restore_sigquit_and_sigint:
00710     (void) rpmsqEnable(-SIGQUIT, NULL);
00711 out_restore_sigint:
00712     (void) rpmsqEnable(-SIGINT, NULL);
00713 out:
00714     (void) DO_UNLOCK ();
00715     return status;
00716 }

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