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            /* ==> Set to 1 to catch SIGCHLD, set to 0 to use waitpid(2).  */
00215             sq->reaper = 1;
00216 /*@-bounds@*/
00217             sq->pipes[0] = sq->pipes[1] = -1;
00218 /*@=bounds@*/
00219 
00220             sq->id = ME();
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             sq->id = NULL;
00243 /*@-bounds@*/
00244             if (sq->pipes[1] > 0)       ret = close(sq->pipes[1]);
00245             if (sq->pipes[0] > 0)       ret = close(sq->pipes[0]);
00246             sq->pipes[0] = sq->pipes[1] = -1;
00247 /*@=bounds@*/
00248 #ifdef  NOTYET  /* rpmpsmWait debugging message needs */
00249             sq->status = 0;
00250             sq->reaped = 0;
00251             sq->child = 0;
00252 #endif
00253             ret = sigrelse(SIGCHLD);
00254         }
00255     }
00256     return ret;
00257 }
00258 
00259 /*@unchecked@*/
00260 sigset_t rpmsqCaught;
00261 
00262 /*@unchecked@*/
00263 /*@-fullinitblock@*/
00264 static struct rpmsig_s {
00265     int signum;
00266     void (*handler) (int signum, void * info, void * context);
00267     int active;
00268     struct sigaction oact;
00269 } rpmsigTbl[] = {
00270     { SIGINT,   rpmsqAction },
00271 #define rpmsigTbl_sigint        (&rpmsigTbl[0])
00272     { SIGQUIT,  rpmsqAction },
00273 #define rpmsigTbl_sigquit       (&rpmsigTbl[1])
00274     { SIGCHLD,  rpmsqAction },
00275 #define rpmsigTbl_sigchld       (&rpmsigTbl[2])
00276     { SIGHUP,   rpmsqAction },
00277 #define rpmsigTbl_sighup        (&rpmsigTbl[3])
00278     { SIGTERM,  rpmsqAction },
00279 #define rpmsigTbl_sigterm       (&rpmsigTbl[4])
00280     { SIGPIPE,  rpmsqAction },
00281 #define rpmsigTbl_sigpipe       (&rpmsigTbl[5])
00282     { -1,       NULL },
00283 };
00284 /*@=fullinitblock@*/
00285 
00286 void rpmsqAction(int signum,
00287                 /*@unused@*/ void * info, /*@unused@*/ void * context)
00288 {
00289     int save = errno;
00290     rpmsig tbl;
00291 
00292     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00293         if (tbl->signum != signum)
00294             continue;
00295 
00296         (void) sigaddset(&rpmsqCaught, signum);
00297 
00298         switch (signum) {
00299         case SIGCHLD:
00300             while (1) {
00301                 rpmsq sq;
00302                 int status = 0;
00303                 pid_t reaped = waitpid(0, &status, WNOHANG);
00304 
00305                 /* XXX errno set to ECHILD/EINVAL/EINTR. */
00306                 if (reaped <= 0)
00307                     /*@innerbreak@*/ break;
00308 
00309                 /* XXX insque(3)/remque(3) are dequeue, not ring. */
00310                 for (sq = rpmsqQueue->q_forw;
00311                      sq != NULL && sq != rpmsqQueue;
00312                      sq = sq->q_forw)
00313                 {
00314                     int ret;
00315 
00316                     if (sq->child != reaped)
00317                         /*@innercontinue@*/ continue;
00318                     sq->reaped = reaped;
00319                     sq->status = status;
00320 
00321                     ret = close(sq->pipes[1]);  sq->pipes[1] = -1;
00322 
00323                     /*@innerbreak@*/ break;
00324                 }
00325             }
00326             /*@switchbreak@*/ break;
00327         default:
00328             /*@switchbreak@*/ break;
00329         }
00330         break;
00331     }
00332     errno = save;
00333 }
00334 
00335 int rpmsqEnable(int signum, /*@null@*/ rpmsqAction_t handler)
00336         /*@globals rpmsigTbl @*/
00337         /*@modifies rpmsigTbl @*/
00338 {
00339     int tblsignum = (signum >= 0 ? signum : -signum);
00340     struct sigaction sa;
00341     rpmsig tbl;
00342     int ret = -1;
00343 
00344     (void) DO_LOCK ();
00345     if (rpmsqQueue->id == NULL)
00346         rpmsqQueue->id = ME();
00347     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00348         if (tblsignum != tbl->signum)
00349             continue;
00350 
00351         if (signum >= 0) {                      /* Enable. */
00352             if (ADD_REF(tbl) <= 0) {
00353                 (void) sigdelset(&rpmsqCaught, tbl->signum);
00354 
00355                 /* XXX Don't set a signal handler if already SIG_IGN */
00356                 (void) sigaction(tbl->signum, NULL, &tbl->oact);
00357                 if (tbl->oact.sa_handler == SIG_IGN)
00358                     continue;
00359 
00360                 (void) sigemptyset (&sa.sa_mask);
00361                 sa.sa_flags = SA_SIGINFO;
00362 #if defined(__LCLINT__) /* XXX glibc has union to track handler prototype. */
00363                 sa.sa_handler = (handler != NULL ? handler : tbl->handler);
00364 #else
00365                 sa.sa_sigaction = (handler != NULL ? handler : tbl->handler);
00366 #endif
00367                 if (sigaction(tbl->signum, &sa, &tbl->oact) < 0) {
00368                     SUB_REF(tbl);
00369                     break;
00370                 }
00371                 tbl->active = 1;                /* XXX just in case */
00372                 if (handler != NULL)
00373                     tbl->handler = handler;
00374             }
00375         } else {                                /* Disable. */
00376             if (SUB_REF(tbl) <= 0) {
00377                 if (sigaction(tbl->signum, &tbl->oact, NULL) < 0)
00378                     break;
00379                 tbl->active = 0;                /* XXX just in case */
00380                 tbl->handler = (handler != NULL ? handler : rpmsqAction);
00381             }
00382         }
00383         ret = tbl->active;
00384         break;
00385     }
00386     (void) DO_UNLOCK ();
00387     return ret;
00388 }
00389 
00390 pid_t rpmsqFork(rpmsq sq)
00391 {
00392     pid_t pid;
00393     int xx;
00394 
00395     if (sq->reaper) {
00396         xx = rpmsqInsert(sq, NULL);
00397 #ifdef _RPMSQ_DEBUG
00398 if (_rpmsq_debug)
00399 fprintf(stderr, "    Enable(%p): %p\n", ME(), sq);
00400 #endif
00401         xx = rpmsqEnable(SIGCHLD, NULL);
00402     }
00403 
00404     xx = pipe(sq->pipes);
00405 
00406     xx = sighold(SIGCHLD);
00407 
00408     pid = fork();
00409     if (pid < (pid_t) 0) {              /* fork failed.  */
00410 /*@-bounds@*/
00411         xx = close(sq->pipes[0]);
00412         xx = close(sq->pipes[1]);
00413         sq->pipes[0] = sq->pipes[1] = -1;
00414 /*@=bounds@*/
00415         goto out;
00416     } else if (pid == (pid_t) 0) {      /* Child. */
00417         int yy;
00418 
00419         /* Block to permit parent time to wait. */
00420 /*@-bounds@*/
00421         xx = close(sq->pipes[1]);
00422         if (sq->reaper)
00423             xx = read(sq->pipes[0], &yy, sizeof(yy));
00424         xx = close(sq->pipes[0]);
00425         sq->pipes[0] = sq->pipes[1] = -1;
00426 /*@=bounds@*/
00427 
00428 #ifdef _RPMSQ_DEBUG
00429 if (_rpmsq_debug)
00430 fprintf(stderr, "     Child(%p): %p child %d\n", ME(), sq, getpid());
00431 #endif
00432 
00433     } else {                            /* Parent. */
00434 
00435         sq->child = pid;
00436 
00437 #ifdef _RPMSQ_DEBUG
00438 if (_rpmsq_debug)
00439 fprintf(stderr, "    Parent(%p): %p child %d\n", ME(), sq, sq->child);
00440 #endif
00441 
00442     }
00443 
00444 out:
00445     xx = sigrelse(SIGCHLD);
00446     return sq->child;
00447 }
00448 
00455 static int rpmsqWaitUnregister(rpmsq sq)
00456         /*@globals fileSystem, internalState @*/
00457         /*@modifies sq, fileSystem, internalState @*/
00458 {
00459     int nothreads = 0;
00460     int ret = 0;
00461     int xx;
00462 
00463 assert(sq->reaper);
00464     /* Protect sq->reaped from handler changes. */
00465     ret = sighold(SIGCHLD);
00466 
00467     /* Start the child, linux often runs child before parent. */
00468 /*@-bounds@*/
00469     if (sq->pipes[0] >= 0)
00470         xx = close(sq->pipes[0]);
00471     if (sq->pipes[1] >= 0)
00472         xx = close(sq->pipes[1]);
00473 /*@=bounds@*/
00474 
00475     /* Re-initialize the pipe to receive SIGCHLD receipt confirmation. */
00476     xx = pipe(sq->pipes);
00477 
00478     /* Put a stopwatch on the time spent waiting to measure performance gain. */
00479     (void) rpmswEnter(&sq->op, -1);
00480 
00481     /* Wait for handler to receive SIGCHLD. */
00482     /*@-infloops@*/
00483     while (ret == 0 && sq->reaped != sq->child) {
00484         if (nothreads)
00485             /* Note that sigpause re-enables SIGCHLD. */
00486             ret = sigpause(SIGCHLD);
00487         else {
00488             xx = sigrelse(SIGCHLD);
00489             
00490             /* Signal handler does close(sq->pipes[1]) triggering 0b EOF read */
00491             if (read(sq->pipes[0], &xx, sizeof(xx)) == 0) {
00492                 xx = close(sq->pipes[0]);       sq->pipes[0] = -1;
00493                 ret = 1;
00494             }
00495 
00496             xx = sighold(SIGCHLD);
00497         }
00498     }
00499     /*@=infloops@*/
00500 
00501     /* Accumulate stopwatch time spent waiting, potential performance gain. */
00502     sq->ms_scriptlets += rpmswExit(&sq->op, -1)/1000;
00503 
00504     xx = sigrelse(SIGCHLD);
00505 
00506 #ifdef _RPMSQ_DEBUG
00507 if (_rpmsq_debug)
00508 fprintf(stderr, "      Wake(%p): %p child %d reaper %d ret %d\n", ME(), sq, sq->child, sq->reaper, ret);
00509 #endif
00510 
00511     /* Remove processed SIGCHLD item from queue. */
00512     xx = rpmsqRemove(sq);
00513 
00514     /* Disable SIGCHLD handler on refcount == 0. */
00515     xx = rpmsqEnable(-SIGCHLD, NULL);
00516 #ifdef _RPMSQ_DEBUG
00517 if (_rpmsq_debug)
00518 fprintf(stderr, "   Disable(%p): %p\n", ME(), sq);
00519 #endif
00520 
00521     return ret;
00522 }
00523 
00524 pid_t rpmsqWait(rpmsq sq)
00525 {
00526 
00527 #ifdef _RPMSQ_DEBUG
00528 if (_rpmsq_debug)
00529 fprintf(stderr, "      Wait(%p): %p child %d reaper %d\n", ME(), sq, sq->child, sq->reaper);
00530 #endif
00531 
00532     if (sq->reaper) {
00533         (void) rpmsqWaitUnregister(sq);
00534     } else {
00535         pid_t reaped;
00536         int status;
00537         do {
00538             reaped = waitpid(sq->child, &status, 0);
00539         } while (reaped >= 0 && reaped != sq->child);
00540         sq->reaped = reaped;
00541         sq->status = status;
00542 #ifdef _RPMSQ_DEBUG
00543 if (_rpmsq_debug)
00544 fprintf(stderr, "   Waitpid(%p): %p child %d reaped %d\n", ME(), sq, sq->child, sq->reaped);
00545 #endif
00546     }
00547 
00548 #ifdef _RPMSQ_DEBUG
00549 if (_rpmsq_debug)
00550 fprintf(stderr, "      Fini(%p): %p child %d status 0x%x\n", ME(), sq, sq->child, sq->status);
00551 #endif
00552 
00553     return sq->reaped;
00554 }
00555 
00556 void * rpmsqThread(void * (*start) (void * arg), void * arg)
00557 {
00558     pthread_t pth;
00559     int ret;
00560 
00561     ret = pthread_create(&pth, NULL, start, arg);
00562     return (ret == 0 ? (void *)pth : NULL);
00563 }
00564 
00565 int rpmsqJoin(void * thread)
00566 {
00567     pthread_t pth = (pthread_t) thread;
00568     if (thread == NULL)
00569         return EINVAL;
00570     return pthread_join(pth, NULL);
00571 }
00572 
00573 int rpmsqThreadEqual(void * thread)
00574 {
00575     pthread_t t1 = (pthread_t) thread;
00576     pthread_t t2 = pthread_self();
00577     return pthread_equal(t1, t2);
00578 }
00579 
00583 static void
00584 sigchld_cancel (void *arg)
00585         /*@globals rpmsigTbl, fileSystem, internalState @*/
00586         /*@modifies rpmsigTbl, fileSystem, internalState @*/
00587 {
00588     pid_t child = *(pid_t *) arg;
00589     pid_t result;
00590 
00591     (void) kill(child, SIGKILL);
00592 
00593     do {
00594         result = waitpid(child, NULL, 0);
00595     } while (result == (pid_t)-1 && errno == EINTR);
00596 
00597     (void) DO_LOCK ();
00598     if (SUB_REF (rpmsigTbl_sigchld) == 0) {
00599         (void) rpmsqEnable(-SIGQUIT, NULL);
00600         (void) rpmsqEnable(-SIGINT, NULL);
00601     }
00602     (void) DO_UNLOCK ();
00603 }
00604 
00608 int
00609 rpmsqExecve (const char ** argv)
00610         /*@globals rpmsigTbl @*/
00611         /*@modifies rpmsigTbl @*/
00612 {
00613     int oldtype;
00614     int status = -1;
00615     pid_t pid = 0;
00616     pid_t result;
00617     sigset_t newMask, oldMask;
00618     rpmsq sq = memset(alloca(sizeof(*sq)), 0, sizeof(*sq));
00619 
00620 #ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
00621         INIT_LOCK ();
00622 #endif
00623 
00624     (void) DO_LOCK ();
00625     if (ADD_REF (rpmsigTbl_sigchld) == 0) {
00626         if (rpmsqEnable(SIGINT, NULL) < 0) {
00627             SUB_REF (rpmsigTbl_sigchld);
00628             goto out;
00629         }
00630         if (rpmsqEnable(SIGQUIT, NULL) < 0) {
00631             SUB_REF (rpmsigTbl_sigchld);
00632             goto out_restore_sigint;
00633         }
00634     }
00635     (void) DO_UNLOCK ();
00636 
00637     (void) sigemptyset (&newMask);
00638     (void) sigaddset (&newMask, SIGCHLD);
00639     if (sigprocmask (SIG_BLOCK, &newMask, &oldMask) < 0) {
00640         (void) DO_LOCK ();
00641         if (SUB_REF (rpmsigTbl_sigchld) == 0)
00642             goto out_restore_sigquit_and_sigint;
00643         goto out;
00644     }
00645 
00646     CLEANUP_HANDLER(sigchld_cancel, &pid, &oldtype);
00647 
00648     pid = fork ();
00649     if (pid < (pid_t) 0) {              /* fork failed.  */
00650         goto out;
00651     } else if (pid == (pid_t) 0) {      /* Child. */
00652 
00653         /* Restore the signals.  */
00654         (void) sigaction (SIGINT, &rpmsigTbl_sigint->oact, NULL);
00655         (void) sigaction (SIGQUIT, &rpmsigTbl_sigquit->oact, NULL);
00656         (void) sigprocmask (SIG_SETMASK, &oldMask, NULL);
00657 
00658         /* Reset rpmsigTbl lock and refcnt. */
00659         INIT_LOCK ();
00660 
00661         (void) execve (argv[0], (char *const *) argv, environ);
00662         _exit (127);
00663     } else {                            /* Parent. */
00664         do {
00665             result = waitpid(pid, &status, 0);
00666         } while (result == (pid_t)-1 && errno == EINTR);
00667         if (result != pid)
00668             status = -1;
00669     }
00670 
00671     CLEANUP_RESET(0, oldtype);
00672 
00673     (void) DO_LOCK ();
00674     if ((SUB_REF (rpmsigTbl_sigchld) == 0 &&
00675         (rpmsqEnable(-SIGINT, NULL) < 0 || rpmsqEnable (-SIGQUIT, NULL) < 0))
00676       || sigprocmask (SIG_SETMASK, &oldMask, NULL) != 0)
00677     {
00678         status = -1;
00679     }
00680     goto out;
00681 
00682 out_restore_sigquit_and_sigint:
00683     (void) rpmsqEnable(-SIGQUIT, NULL);
00684 out_restore_sigint:
00685     (void) rpmsqEnable(-SIGINT, NULL);
00686 out:
00687     (void) DO_UNLOCK ();
00688     return status;
00689 }

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