Main Page | Modules | Data Structures | Directories | File List | Data Fields | Globals | Related Pages

rpmsq.c

Go to the documentation of this file.
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 /*@unchecked@*/
00130 /*@-type@*/
00131 static pthread_mutex_t rpmsigTbl_lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
00132 /*@=type@*/
00133 
00134 #define DO_LOCK()       pthread_mutex_lock(&rpmsigTbl_lock);
00135 #define DO_UNLOCK()     pthread_mutex_unlock(&rpmsigTbl_lock);
00136 #define INIT_LOCK()     \
00137     {   pthread_mutexattr_t attr; \
00138         (void) pthread_mutexattr_init(&attr); \
00139         (void) pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); \
00140         (void) pthread_mutex_init (&rpmsigTbl_lock, &attr); \
00141         (void) pthread_mutexattr_destroy(&attr); \
00142         rpmsigTbl_sigchld->active = 0; \
00143     }
00144 #define ADD_REF(__tbl)  (__tbl)->active++
00145 #define SUB_REF(__tbl)  --(__tbl)->active
00146 #define CLEANUP_HANDLER(__handler, __arg, __oldtypeptr) \
00147     (void) pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, (__oldtypeptr));\
00148         pthread_cleanup_push((__handler), (__arg));
00149 #define CLEANUP_RESET(__execute, __oldtype) \
00150     (void) pthread_cleanup_pop(__execute); \
00151     (void) pthread_setcanceltype ((__oldtype), &(__oldtype));
00152 
00153 #define SAME_THREAD(_a, _b)     pthread_equal(((pthread_t)_a), ((pthread_t)_b))
00154 
00155 #define ME()    ((void *)pthread_self())
00156 
00157 #else
00158 
00159 #define DO_LOCK()
00160 #define DO_UNLOCK()
00161 #define INIT_LOCK()
00162 #define ADD_REF(__tbl)  /*@-noeffect@*/ (0) /*@=noeffect@*/
00163 #define SUB_REF(__tbl)  /*@-noeffect@*/ (0) /*@=noeffect@*/
00164 #define CLEANUP_HANDLER(__handler, __arg, __oldtypeptr)
00165 #define CLEANUP_RESET(__execute, __oldtype)
00166 
00167 #define SAME_THREAD(_a, _b)     (42)
00168 
00169 #define ME()    (((void *)getpid()))
00170 
00171 #endif  /* HAVE_PTHREAD_H */
00172 
00173 #include <rpmsq.h>
00174 
00175 #include "debug.h"
00176 
00177 #define _RPMSQ_DEBUG    0
00178 /*@unchecked@*/
00179 int _rpmsq_debug = _RPMSQ_DEBUG;
00180 
00181 /*@unchecked@*/
00182 static struct rpmsqElem rpmsqRock;
00183 
00184 /*@-compmempass@*/
00185 /*@unchecked@*/
00186 rpmsq rpmsqQueue = &rpmsqRock;
00187 /*@=compmempass@*/
00188 
00189 int rpmsqInsert(void * elem, void * prev)
00190 {
00191     rpmsq sq = (rpmsq) elem;
00192     int ret = -1;
00193 
00194     if (sq != NULL) {
00195 #ifdef _RPMSQ_DEBUG
00196 if (_rpmsq_debug)
00197 fprintf(stderr, "    Insert(%p): %p\n", ME(), sq);
00198 #endif
00199         ret = sighold(SIGCHLD);
00200         if (ret == 0) {
00201             sq->child = 0;
00202             sq->reaped = 0;
00203             sq->status = 0;
00204             sq->reaper = 1;
00205 /*@-bounds@*/
00206             sq->pipes[0] = sq->pipes[1] = -1;
00207 /*@=bounds@*/
00208 
00209             sq->id = ME();
00210             ret = pthread_mutex_init(&sq->mutex, NULL);
00211             ret = pthread_cond_init(&sq->cond, NULL);
00212             insque(elem, (prev != NULL ? prev : rpmsqQueue));
00213             ret = sigrelse(SIGCHLD);
00214         }
00215     }
00216     return ret;
00217 }
00218 
00219 int rpmsqRemove(void * elem)
00220 {
00221     rpmsq sq = (rpmsq) elem;
00222     int ret = -1;
00223 
00224     if (elem != NULL) {
00225 
00226 #ifdef _RPMSQ_DEBUG
00227 if (_rpmsq_debug)
00228 fprintf(stderr, "    Remove(%p): %p\n", ME(), sq);
00229 #endif
00230         ret = sighold (SIGCHLD);
00231         if (ret == 0) {
00232             remque(elem);
00233             ret = pthread_cond_destroy(&sq->cond);
00234             ret = pthread_mutex_destroy(&sq->mutex);
00235             sq->id = NULL;
00236 /*@-bounds@*/
00237             if (sq->pipes[1])   ret = close(sq->pipes[1]);
00238             if (sq->pipes[0])   ret = close(sq->pipes[0]);
00239             sq->pipes[0] = sq->pipes[1] = -1;
00240 /*@=bounds@*/
00241 #ifdef  NOTYET  /* rpmpsmWait debugging message needs */
00242             sq->reaper = 1;
00243             sq->status = 0;
00244             sq->reaped = 0;
00245             sq->child = 0;
00246 #endif
00247             ret = sigrelse(SIGCHLD);
00248         }
00249     }
00250     return ret;
00251 }
00252 
00253 /*@unchecked@*/
00254 sigset_t rpmsqCaught;
00255 
00256 /*@unchecked@*/
00257 /*@-fullinitblock@*/
00258 static struct rpmsig_s {
00259     int signum;
00260     void (*handler) (int signum, void * info, void * context);
00261     int active;
00262     struct sigaction oact;
00263 } rpmsigTbl[] = {
00264     { SIGINT,   rpmsqAction },
00265 #define rpmsigTbl_sigint        (&rpmsigTbl[0])
00266     { SIGQUIT,  rpmsqAction },
00267 #define rpmsigTbl_sigquit       (&rpmsigTbl[1])
00268     { SIGCHLD,  rpmsqAction },
00269 #define rpmsigTbl_sigchld       (&rpmsigTbl[2])
00270     { SIGHUP,   rpmsqAction },
00271 #define rpmsigTbl_sighup        (&rpmsigTbl[3])
00272     { SIGTERM,  rpmsqAction },
00273 #define rpmsigTbl_sigterm       (&rpmsigTbl[4])
00274     { SIGPIPE,  rpmsqAction },
00275 #define rpmsigTbl_sigpipe       (&rpmsigTbl[5])
00276     { -1,       NULL },
00277 };
00278 /*@=fullinitblock@*/
00279 
00280 void rpmsqAction(int signum,
00281                 /*@unused@*/ void * info, /*@unused@*/ void * context)
00282 {
00283     int save = errno;
00284     rpmsig tbl;
00285 
00286     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00287         if (tbl->signum != signum)
00288             continue;
00289 
00290         (void) sigaddset(&rpmsqCaught, signum);
00291 
00292         switch (signum) {
00293         case SIGCHLD:
00294             while (1) {
00295                 rpmsq sq;
00296                 int status = 0;
00297                 pid_t reaped = waitpid(0, &status, WNOHANG);
00298 
00299                 /* XXX errno set to ECHILD/EINVAL/EINTR. */
00300                 if (reaped <= 0)
00301                     /*@innerbreak@*/ break;
00302 
00303                 /* XXX insque(3)/remque(3) are dequeue, not ring. */
00304                 for (sq = rpmsqQueue->q_forw;
00305                      sq != NULL && sq != rpmsqQueue;
00306                      sq = sq->q_forw)
00307                 {
00308                     if (sq->child != reaped)
00309                         /*@innercontinue@*/ continue;
00310                     sq->reaped = reaped;
00311                     sq->status = status;
00312                     (void) pthread_cond_signal(&sq->cond);
00313                     /*@innerbreak@*/ break;
00314                 }
00315             }
00316             /*@switchbreak@*/ break;
00317         default:
00318             /*@switchbreak@*/ break;
00319         }
00320         break;
00321     }
00322     errno = save;
00323 }
00324 
00325 int rpmsqEnable(int signum, /*@null@*/ rpmsqAction_t handler)
00326         /*@globals rpmsigTbl @*/
00327         /*@modifies rpmsigTbl @*/
00328 {
00329     int tblsignum = (signum >= 0 ? signum : -signum);
00330     struct sigaction sa;
00331     rpmsig tbl;
00332     int ret = -1;
00333 
00334     (void) DO_LOCK ();
00335     if (rpmsqQueue->id == NULL)
00336         rpmsqQueue->id = ME();
00337     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00338         if (tblsignum != tbl->signum)
00339             continue;
00340 
00341         if (signum >= 0) {                      /* Enable. */
00342             if (ADD_REF(tbl) <= 0) {
00343                 (void) sigdelset(&rpmsqCaught, tbl->signum);
00344 
00345                 /* XXX Don't set a signal handler if already SIG_IGN */
00346                 (void) sigaction(tbl->signum, NULL, &tbl->oact);
00347                 if (tbl->oact.sa_handler == SIG_IGN)
00348                     continue;
00349 
00350                 (void) sigemptyset (&sa.sa_mask);
00351                 sa.sa_flags = SA_SIGINFO;
00352 #if defined(__LCLINT__) /* XXX glibc has union to track handler prototype. */
00353                 sa.sa_handler = (handler != NULL ? handler : tbl->handler);
00354 #else
00355                 sa.sa_sigaction = (handler != NULL ? handler : tbl->handler);
00356 #endif
00357                 if (sigaction(tbl->signum, &sa, &tbl->oact) < 0) {
00358                     SUB_REF(tbl);
00359                     break;
00360                 }
00361                 tbl->active = 1;                /* XXX just in case */
00362                 if (handler != NULL)
00363                     tbl->handler = handler;
00364             }
00365         } else {                                /* Disable. */
00366             if (SUB_REF(tbl) <= 0) {
00367                 if (sigaction(tbl->signum, &tbl->oact, NULL) < 0)
00368                     break;
00369                 tbl->active = 0;                /* XXX just in case */
00370                 tbl->handler = (handler != NULL ? handler : rpmsqAction);
00371             }
00372         }
00373         ret = tbl->active;
00374         break;
00375     }
00376     (void) DO_UNLOCK ();
00377     return ret;
00378 }
00379 
00380 pid_t rpmsqFork(rpmsq sq)
00381 {
00382     pid_t pid;
00383     int xx;
00384 
00385     if (sq->reaper) {
00386         xx = rpmsqInsert(sq, NULL);
00387 #ifdef _RPMSQ_DEBUG
00388 if (_rpmsq_debug)
00389 fprintf(stderr, "    Enable(%p): %p\n", ME(), sq);
00390 #endif
00391         xx = rpmsqEnable(SIGCHLD, NULL);
00392     }
00393 
00394     xx = pipe(sq->pipes);
00395 
00396     xx = sighold(SIGCHLD);
00397 
00398     pid = fork();
00399     if (pid < (pid_t) 0) {              /* fork failed.  */
00400 /*@-bounds@*/
00401         xx = close(sq->pipes[0]);
00402         xx = close(sq->pipes[1]);
00403         sq->pipes[0] = sq->pipes[1] = -1;
00404 /*@=bounds@*/
00405         goto out;
00406     } else if (pid == (pid_t) 0) {      /* Child. */
00407         int yy;
00408 
00409         /* Block to permit parent time to wait. */
00410 /*@-bounds@*/
00411         xx = close(sq->pipes[1]);
00412         xx = read(sq->pipes[0], &yy, sizeof(yy));
00413         xx = close(sq->pipes[0]);
00414         sq->pipes[0] = sq->pipes[1] = -1;
00415 /*@=bounds@*/
00416 
00417 #ifdef _RPMSQ_DEBUG
00418 if (_rpmsq_debug)
00419 fprintf(stderr, "     Child(%p): %p child %d\n", ME(), sq, getpid());
00420 #endif
00421 
00422     } else {                            /* Parent. */
00423 
00424         sq->child = pid;
00425 
00426 #ifdef _RPMSQ_DEBUG
00427 if (_rpmsq_debug)
00428 fprintf(stderr, "    Parent(%p): %p child %d\n", ME(), sq, sq->child);
00429 #endif
00430 
00431     }
00432 
00433 out:
00434     xx = sigrelse(SIGCHLD);
00435     return sq->child;
00436 }
00437 
00444 static int rpmsqWaitUnregister(rpmsq sq)
00445         /*@globals fileSystem, internalState @*/
00446         /*@modifies sq, fileSystem, internalState @*/
00447 {
00448     int nothreads = 0;
00449     int ret = 0;
00450     int xx;
00451 
00452     /* Protect sq->reaped from handler changes. */
00453     ret = sighold(SIGCHLD);
00454 
00455     /* Initialize the cond var mutex. */
00456     if (!nothreads)
00457         ret = pthread_mutex_lock(&sq->mutex);
00458 
00459     /* Start the child, linux often runs child before parent. */
00460 /*@-bounds@*/
00461     if (sq->pipes[0] >= 0)
00462         xx = close(sq->pipes[0]);
00463     if (sq->pipes[1] >= 0)
00464         xx = close(sq->pipes[1]);
00465     sq->pipes[0] = sq->pipes[1] = -1;
00466 /*@=bounds@*/
00467 
00468     /* Put a stopwatch on the time spent waiting to measure performance gain. */
00469     (void) rpmswEnter(&sq->op, -1);
00470 
00471     /* Wait for handler to receive SIGCHLD. */
00472     /*@-infloops@*/
00473     while (ret == 0 && sq->reaped != sq->child) {
00474         if (nothreads)
00475             /* Note that sigpause re-enables SIGCHLD. */
00476             ret = sigpause(SIGCHLD);
00477         else {
00478             xx = sigrelse(SIGCHLD);
00479             ret = pthread_cond_wait(&sq->cond, &sq->mutex);
00480             xx = sighold(SIGCHLD);
00481         }
00482     }
00483     /*@=infloops@*/
00484 
00485     /* Accumulate stopwatch time spent waiting, potential performance gain. */
00486     sq->ms_scriptlets += rpmswExit(&sq->op, -1)/1000;
00487 
00488     /* Tear down cond var mutex, our child has been reaped. */
00489     if (!nothreads)
00490         xx = pthread_mutex_unlock(&sq->mutex);
00491     xx = sigrelse(SIGCHLD);
00492 
00493 #ifdef _RPMSQ_DEBUG
00494 if (_rpmsq_debug)
00495 fprintf(stderr, "      Wake(%p): %p child %d reaper %d ret %d\n", ME(), sq, sq->child, sq->reaper, ret);
00496 #endif
00497 
00498     /* Remove processed SIGCHLD item from queue. */
00499     xx = rpmsqRemove(sq);
00500 
00501     /* Disable SIGCHLD handler on refcount == 0. */
00502     xx = rpmsqEnable(-SIGCHLD, NULL);
00503 #ifdef _RPMSQ_DEBUG
00504 if (_rpmsq_debug)
00505 fprintf(stderr, "   Disable(%p): %p\n", ME(), sq);
00506 #endif
00507 
00508     return ret;
00509 }
00510 
00511 pid_t rpmsqWait(rpmsq sq)
00512 {
00513 
00514 #ifdef _RPMSQ_DEBUG
00515 if (_rpmsq_debug)
00516 fprintf(stderr, "      Wait(%p): %p child %d reaper %d\n", ME(), sq, sq->child, sq->reaper);
00517 #endif
00518 
00519     if (sq->reaper) {
00520         (void) rpmsqWaitUnregister(sq);
00521     } else {
00522         pid_t reaped;
00523         int status;
00524         do {
00525             reaped = waitpid(sq->child, &status, 0);
00526         } while (reaped >= 0 && reaped != sq->child);
00527         sq->reaped = reaped;
00528         sq->status = status;
00529 #ifdef _RPMSQ_DEBUG
00530 if (_rpmsq_debug)
00531 fprintf(stderr, "   Waitpid(%p): %p child %d reaped %d\n", ME(), sq, sq->child, sq->reaped);
00532 #endif
00533     }
00534 
00535 #ifdef _RPMSQ_DEBUG
00536 if (_rpmsq_debug)
00537 fprintf(stderr, "      Fini(%p): %p child %d status 0x%x\n", ME(), sq, sq->child, sq->status);
00538 #endif
00539 
00540     return sq->reaped;
00541 }
00542 
00543 void * rpmsqThread(void * (*start) (void * arg), void * arg)
00544 {
00545     pthread_t pth;
00546     int ret;
00547 
00548     ret = pthread_create(&pth, NULL, start, arg);
00549     return (ret == 0 ? (void *)pth : NULL);
00550 }
00551 
00552 int rpmsqJoin(void * thread)
00553 {
00554     pthread_t pth = (pthread_t) thread;
00555     if (thread == NULL)
00556         return EINVAL;
00557     return pthread_join(pth, NULL);
00558 }
00559 
00560 int rpmsqThreadEqual(void * thread)
00561 {
00562     pthread_t t1 = (pthread_t) thread;
00563     pthread_t t2 = pthread_self();
00564     return pthread_equal(t1, t2);
00565 }
00566 
00570 static void
00571 sigchld_cancel (void *arg)
00572         /*@globals rpmsigTbl, fileSystem, internalState @*/
00573         /*@modifies rpmsigTbl, fileSystem, internalState @*/
00574 {
00575     pid_t child = *(pid_t *) arg;
00576     pid_t result;
00577 
00578     (void) kill(child, SIGKILL);
00579 
00580     do {
00581         result = waitpid(child, NULL, 0);
00582     } while (result == (pid_t)-1 && errno == EINTR);
00583 
00584     (void) DO_LOCK ();
00585     if (SUB_REF (rpmsigTbl_sigchld) == 0) {
00586         (void) rpmsqEnable(-SIGQUIT, NULL);
00587         (void) rpmsqEnable(-SIGINT, NULL);
00588     }
00589     (void) DO_UNLOCK ();
00590 }
00591 
00595 int
00596 rpmsqExecve (const char ** argv)
00597         /*@globals rpmsigTbl @*/
00598         /*@modifies rpmsigTbl @*/
00599 {
00600     int oldtype;
00601     int status = -1;
00602     pid_t pid = 0;
00603     pid_t result;
00604     sigset_t newMask, oldMask;
00605     rpmsq sq = memset(alloca(sizeof(*sq)), 0, sizeof(*sq));
00606 
00607     (void) DO_LOCK ();
00608     if (ADD_REF (rpmsigTbl_sigchld) == 0) {
00609         if (rpmsqEnable(SIGINT, NULL) < 0) {
00610             SUB_REF (rpmsigTbl_sigchld);
00611             goto out;
00612         }
00613         if (rpmsqEnable(SIGQUIT, NULL) < 0) {
00614             SUB_REF (rpmsigTbl_sigchld);
00615             goto out_restore_sigint;
00616         }
00617     }
00618     (void) DO_UNLOCK ();
00619 
00620     (void) sigemptyset (&newMask);
00621     (void) sigaddset (&newMask, SIGCHLD);
00622     if (sigprocmask (SIG_BLOCK, &newMask, &oldMask) < 0) {
00623         (void) DO_LOCK ();
00624         if (SUB_REF (rpmsigTbl_sigchld) == 0)
00625             goto out_restore_sigquit_and_sigint;
00626         goto out;
00627     }
00628 
00629     CLEANUP_HANDLER(sigchld_cancel, &pid, &oldtype);
00630 
00631     pid = fork ();
00632     if (pid < (pid_t) 0) {              /* fork failed.  */
00633         goto out;
00634     } else if (pid == (pid_t) 0) {      /* Child. */
00635 
00636         /* Restore the signals.  */
00637         (void) sigaction (SIGINT, &rpmsigTbl_sigint->oact, NULL);
00638         (void) sigaction (SIGQUIT, &rpmsigTbl_sigquit->oact, NULL);
00639         (void) sigprocmask (SIG_SETMASK, &oldMask, NULL);
00640 
00641         /* Reset rpmsigTbl lock and refcnt. */
00642         INIT_LOCK ();
00643 
00644         (void) execve (argv[0], (char *const *) argv, environ);
00645         _exit (127);
00646     } else {                            /* Parent. */
00647         do {
00648             result = waitpid(pid, &status, 0);
00649         } while (result == (pid_t)-1 && errno == EINTR);
00650         if (result != pid)
00651             status = -1;
00652     }
00653 
00654     CLEANUP_RESET(0, oldtype);
00655 
00656     (void) DO_LOCK ();
00657     if ((SUB_REF (rpmsigTbl_sigchld) == 0 &&
00658         (rpmsqEnable(-SIGINT, NULL) < 0 || rpmsqEnable (-SIGQUIT, NULL) < 0))
00659       || sigprocmask (SIG_SETMASK, &oldMask, NULL) != 0)
00660     {
00661         status = -1;
00662     }
00663     goto out;
00664 
00665 out_restore_sigquit_and_sigint:
00666     (void) rpmsqEnable(-SIGQUIT, NULL);
00667 out_restore_sigint:
00668     (void) rpmsqEnable(-SIGINT, NULL);
00669 out:
00670     (void) DO_UNLOCK ();
00671     return status;
00672 }

Generated on Mon Nov 1 21:54:21 2004 for rpm by  doxygen 1.3.9.1