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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 #if !defined(__QNX__)
00122 #include <sys/signal.h>
00123 #endif
00124 #include <sys/wait.h>
00125 #include <search.h>
00126 
00127 /* portability fallback for sighold(3) */
00128 #if !defined(HAVE_SIGHOLD) && defined(HAVE_SIGPROCMASK) && defined(HAVE_SIGADDSET)
00129 static int __RPM_sighold(int sig)
00130 {
00131     sigset_t set;
00132     if (sigprocmask(SIG_SETMASK, NULL, &set) < 0)
00133         return -1;
00134     if (sigaddset(&set, sig) < 0)
00135         return -1;
00136     return sigprocmask(SIG_SETMASK, &set, NULL);
00137 }
00138 #define sighold(sig) __RPM_sighold(sig)
00139 #endif
00140 
00141 /* portability fallback for sigrelse(3) */
00142 #if !defined(HAVE_SIGRELSE) && defined(HAVE_SIGPROCMASK) && defined(HAVE_SIGDELSET)
00143 static int __RPM_sigrelse(int sig)
00144 {
00145     sigset_t set;
00146     if (sigprocmask(SIG_SETMASK, NULL, &set) < 0)
00147         return -1;
00148     if (sigdelset(&set, sig) < 0)
00149         return -1;
00150     return sigprocmask(SIG_SETMASK, &set, NULL);
00151 }
00152 #define sigrelse(sig) __RPM_sigrelse(sig)
00153 #endif
00154 
00155 /* portability fallback for sigpause(3) */
00156 #if !defined(HAVE_SIGPAUSE) && defined(HAVE_SIGEMPTYSET) && defined(HAVE_SIGADDSET) && defined(HAVE_SIGSUSPEND)
00157 static int __RPM_sigpause(int sig)
00158 {
00159     sigset_t set;
00160     if (sigemptyset(&set) < 0)
00161         return -1;
00162     if (sigaddset(&set, sig) < 0)
00163         return -1;
00164     return sigsuspend(&set);
00165 }
00166 #define sigpause(sig) __RPM_sigpause(sig)
00167 #endif
00168 
00169 /* portability fallback for insque(3)/remque(3) */
00170 #if defined(__CYGWIN__) || defined(__MINGW32__) || defined(__QNX__)
00171 struct qelem {
00172   struct qelem *q_forw;
00173   struct qelem *q_back;
00174 };
00175 
00176 static void __insque(struct qelem * elem, struct qelem * pred)
00177 {
00178   elem -> q_forw = pred -> q_forw;
00179   pred -> q_forw -> q_back = elem;
00180   elem -> q_back = pred;
00181   pred -> q_forw = elem;
00182 }
00183 #define insque(_e, _p)  __insque((_e), (_p))
00184 
00185 static  void __remque(struct qelem * elem)
00186 {
00187   elem -> q_forw -> q_back = elem -> q_back;
00188   elem -> q_back -> q_forw = elem -> q_forw;
00189 }
00190 #define remque(_e)      __remque(_e)
00191 #endif
00192 
00193 #if defined(HAVE_PTHREAD_H)
00194 
00195 # if !defined(__QNX__)
00196 /* XXX suggested in bugzilla #159024 */
00197 #if PTHREAD_MUTEX_DEFAULT != PTHREAD_MUTEX_NORMAL
00198   #error RPM expects PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_NORMAL
00199 #endif
00200 # endif
00201 
00202 #ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
00203 /*@unchecked@*/
00204 static pthread_mutex_t rpmsigTbl_lock = PTHREAD_MUTEX_INITIALIZER;
00205 #else
00206 /*@unchecked@*/
00207 /*@-type@*/
00208 static pthread_mutex_t rpmsigTbl_lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
00209 /*@=type@*/
00210 #endif
00211 
00212 #define DO_LOCK()       pthread_mutex_lock(&rpmsigTbl_lock);
00213 #define DO_UNLOCK()     pthread_mutex_unlock(&rpmsigTbl_lock);
00214 #define INIT_LOCK()     \
00215     {   pthread_mutexattr_t attr; \
00216         (void) pthread_mutexattr_init(&attr); \
00217         (void) pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); \
00218         (void) pthread_mutex_init (&rpmsigTbl_lock, &attr); \
00219         (void) pthread_mutexattr_destroy(&attr); \
00220         rpmsigTbl_sigchld->active = 0; \
00221     }
00222 #define ADD_REF(__tbl)  (__tbl)->active++
00223 #define SUB_REF(__tbl)  --(__tbl)->active
00224 #define CLEANUP_HANDLER(__handler, __arg, __oldtypeptr) \
00225     (void) pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, (__oldtypeptr));\
00226         pthread_cleanup_push((__handler), (__arg));
00227 #define CLEANUP_RESET(__execute, __oldtype) \
00228     pthread_cleanup_pop(__execute); \
00229     (void) pthread_setcanceltype ((__oldtype), &(__oldtype));
00230 
00231 #define SAME_THREAD(_a, _b)     pthread_equal(((pthread_t)_a), ((pthread_t)_b))
00232 
00233 #define ME() __tid2vp(pthread_self())
00234 /*@shared@*/
00235 static void *__tid2vp(pthread_t tid)
00236         /*@*/
00237 {
00238     union { pthread_t tid; /*@shared@*/ void *vp; } u;
00239     u.tid = tid;
00240     return u.vp;
00241 }
00242 
00243 #else
00244 
00245 #define DO_LOCK() (0)
00246 #define DO_UNLOCK() (0)
00247 #define INIT_LOCK() ((void)0)
00248 #define ADD_REF(__tbl)  /*@-noeffect@*/ (0) /*@=noeffect@*/
00249 #define SUB_REF(__tbl)  /*@-noeffect@*/ (0) /*@=noeffect@*/
00250 #define CLEANUP_HANDLER(__handler, __arg, __oldtypeptr) ((void)0)
00251 #define CLEANUP_RESET(__execute, __oldtype) ((void)0)
00252 
00253 #define SAME_THREAD(_a, _b)     (42)
00254 
00255 #define ME() __pid2vp(getpid())
00256 /*@shared@*/
00257 static void *__pid2vp(pid_t pid)
00258         /*@*/
00259 {
00260     union { pid_t pid; /*@shared@*/ void *vp; } u;
00261     u.pid = pid;
00262     return u.vp;
00263 }
00264 
00265 #endif  /* HAVE_PTHREAD_H */
00266 
00267 #define _RPMSQ_INTERNAL
00268 #include <rpmsq.h>
00269 
00270 #include "debug.h"
00271 
00272 #define _RPMSQ_DEBUG    0
00273 /*@unchecked@*/
00274 int _rpmsq_debug = _RPMSQ_DEBUG;
00275 
00276 /*@unchecked@*/
00277 static struct rpmsqElem rpmsqRock;
00278 
00279 /*@-compmempass@*/
00280 /*@unchecked@*/
00281 rpmsq rpmsqQueue = &rpmsqRock;
00282 /*@=compmempass@*/
00283 
00284 int rpmsqInsert(void * elem, void * prev)
00285 {
00286     rpmsq sq = (rpmsq) elem;
00287     int ret = -1;
00288 
00289     if (sq != NULL) {
00290 #ifdef _RPMSQ_DEBUG
00291 if (_rpmsq_debug)
00292 fprintf(stderr, "    Insert(%p): %p\n", ME(), sq);
00293 #endif
00294         ret = sighold(SIGCHLD);
00295         if (ret == 0) {
00296             sq->child = 0;
00297             sq->reaped = 0;
00298             sq->status = 0;
00299            /* ==> Set to 1 to catch SIGCHLD, set to 0 to use waitpid(2).  */
00300             sq->reaper = 1;
00301             sq->pipes[0] = sq->pipes[1] = -1;
00302 
00303             sq->id = ME();
00304 /*@-noeffect@*/
00305             insque(elem, (prev != NULL ? prev : rpmsqQueue));
00306 /*@=noeffect@*/
00307             ret = sigrelse(SIGCHLD);
00308         }
00309     }
00310     return ret;
00311 }
00312 
00313 int rpmsqRemove(void * elem)
00314 {
00315     rpmsq sq = (rpmsq) elem;
00316     int ret = -1;
00317 
00318     if (elem != NULL) {
00319 
00320 #ifdef _RPMSQ_DEBUG
00321 if (_rpmsq_debug)
00322 fprintf(stderr, "    Remove(%p): %p\n", ME(), sq);
00323 #endif
00324         ret = sighold (SIGCHLD);
00325         if (ret == 0) {
00326 /*@-noeffect@*/
00327             remque(elem);
00328 /*@=noeffect@*/
00329             sq->id = NULL;
00330             if (sq->pipes[1] > 0)       ret = close(sq->pipes[1]);
00331             if (sq->pipes[0] > 0)       ret = close(sq->pipes[0]);
00332             sq->pipes[0] = sq->pipes[1] = -1;
00333 #ifdef  NOTYET  /* rpmpsmWait debugging message needs */
00334             sq->status = 0;
00335             sq->reaped = 0;
00336             sq->child = 0;
00337 #endif
00338             ret = sigrelse(SIGCHLD);
00339         }
00340     }
00341     return ret;
00342 }
00343 
00344 /*@unchecked@*/
00345 sigset_t rpmsqCaught;
00346 
00347 /*@unchecked@*/
00348 /*@-fullinitblock@*/
00349 static struct rpmsig_s {
00350     int signum;
00351     void (*handler) (int signum, void * info, void * context);
00352     int active;
00353     struct sigaction oact;
00354 } rpmsigTbl[] = {
00355     { SIGINT,   rpmsqAction },
00356 #define rpmsigTbl_sigint        (&rpmsigTbl[0])
00357     { SIGQUIT,  rpmsqAction },
00358 #define rpmsigTbl_sigquit       (&rpmsigTbl[1])
00359     { SIGCHLD,  rpmsqAction },
00360 #define rpmsigTbl_sigchld       (&rpmsigTbl[2])
00361     { SIGHUP,   rpmsqAction },
00362 #define rpmsigTbl_sighup        (&rpmsigTbl[3])
00363     { SIGTERM,  rpmsqAction },
00364 #define rpmsigTbl_sigterm       (&rpmsigTbl[4])
00365     { SIGPIPE,  rpmsqAction },
00366 #define rpmsigTbl_sigpipe       (&rpmsigTbl[5])
00367     { -1,       NULL },
00368 };
00369 /*@=fullinitblock@*/
00370 
00371 void rpmsqAction(int signum,
00372                 /*@unused@*/ void * info, /*@unused@*/ void * context)
00373 {
00374     int save = errno;
00375     rpmsig tbl;
00376 
00377     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00378         if (tbl->signum != signum)
00379             continue;
00380 
00381         (void) sigaddset(&rpmsqCaught, signum);
00382 
00383         switch (signum) {
00384         case SIGCHLD:
00385             while (1) {
00386                 rpmsq sq;
00387                 int status = 0;
00388                 pid_t reaped = waitpid(0, &status, WNOHANG);
00389 
00390                 /* XXX errno set to ECHILD/EINVAL/EINTR. */
00391                 if (reaped <= 0)
00392                     /*@innerbreak@*/ break;
00393 
00394                 /* XXX insque(3)/remque(3) are dequeue, not ring. */
00395                 for (sq = rpmsqQueue->q_forw;
00396                      sq != NULL && sq != rpmsqQueue;
00397                      sq = sq->q_forw)
00398                 {
00399                     int ret;
00400 
00401                     if (sq->child != reaped)
00402                         /*@innercontinue@*/ continue;
00403                     sq->reaped = reaped;
00404                     sq->status = status;
00405 
00406                     ret = close(sq->pipes[1]);  sq->pipes[1] = -1;
00407 
00408                     /*@innerbreak@*/ break;
00409                 }
00410             }
00411             /*@switchbreak@*/ break;
00412         default:
00413             /*@switchbreak@*/ break;
00414         }
00415         break;
00416     }
00417     errno = save;
00418 }
00419 
00420 int rpmsqEnable(int signum, /*@null@*/ rpmsqAction_t handler)
00421         /*@globals rpmsigTbl @*/
00422         /*@modifies rpmsigTbl @*/
00423 {
00424     int tblsignum = (signum >= 0 ? signum : -signum);
00425     struct sigaction sa;
00426     rpmsig tbl;
00427     int ret = -1;
00428 
00429     (void) DO_LOCK ();
00430     if (rpmsqQueue->id == NULL)
00431         rpmsqQueue->id = ME();
00432     for (tbl = rpmsigTbl; tbl->signum >= 0; tbl++) {
00433         if (tblsignum != tbl->signum)
00434             continue;
00435 
00436         if (signum >= 0) {                      /* Enable. */
00437             if (ADD_REF(tbl) <= 0) {
00438                 (void) sigdelset(&rpmsqCaught, tbl->signum);
00439 
00440                 /* XXX Don't set a signal handler if already SIG_IGN */
00441                 (void) sigaction(tbl->signum, NULL, &tbl->oact);
00442                 if (tbl->oact.sa_handler == SIG_IGN)
00443                     continue;
00444 
00445                 (void) sigemptyset (&sa.sa_mask);
00446                 sa.sa_flags = SA_SIGINFO;
00447 #if defined(__LCLINT__) /* XXX glibc has union to track handler prototype. */
00448                 sa.sa_handler = (handler != NULL ? handler : tbl->handler);
00449 #else
00450                 sa.sa_sigaction = (void *) (handler != NULL ? handler : tbl->handler);
00451 #endif
00452                 if (sigaction(tbl->signum, &sa, &tbl->oact) < 0) {
00453                     (void)SUB_REF(tbl);
00454                     break;
00455                 }
00456                 tbl->active = 1;                /* XXX just in case */
00457                 if (handler != NULL)
00458                     tbl->handler = handler;
00459             }
00460         } else {                                /* Disable. */
00461             if (SUB_REF(tbl) <= 0) {
00462                 if (sigaction(tbl->signum, &tbl->oact, NULL) < 0)
00463                     break;
00464                 tbl->active = 0;                /* XXX just in case */
00465                 tbl->handler = (handler != NULL ? handler : rpmsqAction);
00466             }
00467         }
00468         ret = tbl->active;
00469         break;
00470     }
00471     (void) DO_UNLOCK ();
00472     return ret;
00473 }
00474 
00475 pid_t rpmsqFork(rpmsq sq)
00476 {
00477     pid_t pid;
00478     int xx;
00479 
00480     if (sq->reaper) {
00481         xx = rpmsqInsert(sq, NULL);
00482 #ifdef _RPMSQ_DEBUG
00483 if (_rpmsq_debug)
00484 fprintf(stderr, "    Enable(%p): %p\n", ME(), sq);
00485 #endif
00486         xx = rpmsqEnable(SIGCHLD, NULL);
00487     }
00488 
00489     xx = pipe(sq->pipes);
00490 
00491     xx = sighold(SIGCHLD);
00492 
00493     pid = fork();
00494     if (pid < (pid_t) 0) {              /* fork failed.  */
00495         sq->child = (pid_t)-1;
00496         xx = close(sq->pipes[0]);
00497         xx = close(sq->pipes[1]);
00498         sq->pipes[0] = sq->pipes[1] = -1;
00499         goto out;
00500     } else if (pid == (pid_t) 0) {      /* Child. */
00501         int yy;
00502 
00503         /* Block to permit parent time to wait. */
00504         xx = close(sq->pipes[1]);
00505         if (sq->reaper)
00506             xx = (int)read(sq->pipes[0], &yy, sizeof(yy));
00507         xx = close(sq->pipes[0]);
00508         sq->pipes[0] = sq->pipes[1] = -1;
00509 
00510 #ifdef _RPMSQ_DEBUG
00511 if (_rpmsq_debug)
00512 fprintf(stderr, "     Child(%p): %p child %d\n", ME(), sq, (int)getpid());
00513 #endif
00514 
00515     } else {                            /* Parent. */
00516 
00517         sq->child = pid;
00518 
00519 #ifdef _RPMSQ_DEBUG
00520 if (_rpmsq_debug)
00521 fprintf(stderr, "    Parent(%p): %p child %d\n", ME(), sq, (int)sq->child);
00522 #endif
00523 
00524     }
00525 
00526 out:
00527     xx = sigrelse(SIGCHLD);
00528     return sq->child;
00529 }
00530 
00537 static int rpmsqWaitUnregister(rpmsq sq)
00538         /*@globals fileSystem, internalState @*/
00539         /*@modifies sq, fileSystem, internalState @*/
00540 {
00541     int nothreads = 0;
00542     int ret = 0;
00543     int xx;
00544 
00545 assert(sq->reaper);
00546     /* Protect sq->reaped from handler changes. */
00547     ret = sighold(SIGCHLD);
00548 
00549     /* Start the child, linux often runs child before parent. */
00550     if (sq->pipes[0] >= 0)
00551         xx = close(sq->pipes[0]);
00552     if (sq->pipes[1] >= 0)
00553         xx = close(sq->pipes[1]);
00554 
00555     /* Re-initialize the pipe to receive SIGCHLD receipt confirmation. */
00556     xx = pipe(sq->pipes);
00557 
00558     /* Put a stopwatch on the time spent waiting to measure performance gain. */
00559     (void) rpmswEnter(&sq->op, -1);
00560 
00561     /* Wait for handler to receive SIGCHLD. */
00562     /*@-infloops@*/
00563     while (ret == 0 && sq->reaped != sq->child) {
00564         if (nothreads)
00565             /* Note that sigpause re-enables SIGCHLD. */
00566             ret = sigpause(SIGCHLD);
00567         else {
00568             xx = sigrelse(SIGCHLD);
00569             
00570             /* Signal handler does close(sq->pipes[1]) triggering 0b EOF read */
00571             if (read(sq->pipes[0], &xx, sizeof(xx)) == 0) {
00572                 xx = close(sq->pipes[0]);       sq->pipes[0] = -1;
00573                 ret = 1;
00574             }
00575 
00576             xx = sighold(SIGCHLD);
00577         }
00578     }
00579     /*@=infloops@*/
00580 
00581     /* Accumulate stopwatch time spent waiting, potential performance gain. */
00582     sq->ms_scriptlets += rpmswExit(&sq->op, -1)/1000;
00583 
00584     xx = sigrelse(SIGCHLD);
00585 
00586 #ifdef _RPMSQ_DEBUG
00587 if (_rpmsq_debug)
00588 fprintf(stderr, "      Wake(%p): %p child %d reaper %d ret %d\n", ME(), sq, (int)sq->child, sq->reaper, ret);
00589 #endif
00590 
00591     /* Remove processed SIGCHLD item from queue. */
00592     xx = rpmsqRemove(sq);
00593 
00594     /* Disable SIGCHLD handler on refcount == 0. */
00595     xx = rpmsqEnable(-SIGCHLD, NULL);
00596 #ifdef _RPMSQ_DEBUG
00597 if (_rpmsq_debug)
00598 fprintf(stderr, "   Disable(%p): %p\n", ME(), sq);
00599 #endif
00600 
00601     return ret;
00602 }
00603 
00604 pid_t rpmsqWait(rpmsq sq)
00605 {
00606 
00607 #ifdef _RPMSQ_DEBUG
00608 if (_rpmsq_debug)
00609 fprintf(stderr, "      Wait(%p): %p child %d reaper %d\n", ME(), sq, (int)sq->child, sq->reaper);
00610 #endif
00611 
00612     if (sq->reaper) {
00613         (void) rpmsqWaitUnregister(sq);
00614     } else {
00615         pid_t reaped;
00616         int status;
00617         do {
00618             reaped = waitpid(sq->child, &status, 0);
00619         } while (reaped >= 0 && reaped != sq->child);
00620         sq->reaped = reaped;
00621         sq->status = status;
00622 #ifdef _RPMSQ_DEBUG
00623 if (_rpmsq_debug)
00624 fprintf(stderr, "   Waitpid(%p): %p child %d reaped %d\n", ME(), sq, (int)sq->child, (int)sq->reaped);
00625 #endif
00626     }
00627 
00628 #ifdef _RPMSQ_DEBUG
00629 if (_rpmsq_debug)
00630 fprintf(stderr, "      Fini(%p): %p child %d status 0x%x\n", ME(), sq, (int)sq->child, sq->status);
00631 #endif
00632 
00633     return sq->reaped;
00634 }
00635 
00636 void * rpmsqThread(void * (*start) (void * arg), void * arg)
00637 {
00638 #if defined(HAVE_PTHREAD_H)
00639     pthread_t pth;
00640     int ret;
00641 
00642     ret = pthread_create(&pth, NULL, start, arg);
00643     return (ret == 0 ? (void *)pth : NULL);
00644 #else
00645     return NULL;
00646 #endif
00647 }
00648 
00649 int rpmsqJoin(void * thread)
00650 {
00651 #if defined(HAVE_PTHREAD_H)
00652     pthread_t pth = (pthread_t) thread;
00653     if (thread == NULL)
00654         return EINVAL;
00655     return pthread_join(pth, NULL);
00656 #else
00657     return EINVAL;
00658 #endif
00659 }
00660 
00661 int rpmsqThreadEqual(void * thread)
00662 {
00663 #if defined(HAVE_PTHREAD_H)
00664     pthread_t t1 = (pthread_t) thread;
00665     pthread_t t2 = pthread_self();
00666     return pthread_equal(t1, t2);
00667 #else
00668     return 0;
00669 #endif
00670 }
00671 
00675 #if defined(HAVE_PTHREAD_H)
00676 static void
00677 sigchld_cancel (void *arg)
00678         /*@globals rpmsigTbl, fileSystem, internalState @*/
00679         /*@modifies rpmsigTbl, fileSystem, internalState @*/
00680 {
00681     pid_t child = *(pid_t *) arg;
00682     pid_t result;
00683 
00684     (void) kill(child, SIGKILL);
00685 
00686     do {
00687         result = waitpid(child, NULL, 0);
00688     } while (result == (pid_t)-1 && errno == EINTR);
00689 
00690     (void) DO_LOCK ();
00691     if (SUB_REF (rpmsigTbl_sigchld) == 0) {
00692         (void) rpmsqEnable(-SIGQUIT, NULL);
00693         (void) rpmsqEnable(-SIGINT, NULL);
00694     }
00695     (void) DO_UNLOCK ();
00696 }
00697 #endif
00698 
00702 int
00703 rpmsqExecve (const char ** argv)
00704         /*@globals rpmsigTbl @*/
00705         /*@modifies rpmsigTbl @*/
00706 {
00707 #if defined(HAVE_PTHREAD_H)
00708     int oldtype;
00709 #endif
00710     int status = -1;
00711     pid_t pid = 0;
00712     pid_t result;
00713     sigset_t newMask, oldMask;
00714     rpmsq sq = memset(alloca(sizeof(*sq)), 0, sizeof(*sq));
00715 
00716 #ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
00717         INIT_LOCK ();
00718 #endif
00719 
00720     (void) DO_LOCK ();
00721     if (ADD_REF (rpmsigTbl_sigchld) == 0) {
00722         if (rpmsqEnable(SIGINT, NULL) < 0) {
00723             (void) SUB_REF (rpmsigTbl_sigchld);
00724             goto out;
00725         }
00726         if (rpmsqEnable(SIGQUIT, NULL) < 0) {
00727             (void) SUB_REF (rpmsigTbl_sigchld);
00728             goto out_restore_sigint;
00729         }
00730     }
00731     (void) DO_UNLOCK ();
00732 
00733     (void) sigemptyset (&newMask);
00734     (void) sigaddset (&newMask, SIGCHLD);
00735     if (sigprocmask (SIG_BLOCK, &newMask, &oldMask) < 0) {
00736         (void) DO_LOCK ();
00737         if (SUB_REF (rpmsigTbl_sigchld) == 0)
00738             goto out_restore_sigquit_and_sigint;
00739         goto out;
00740     }
00741 
00742 /*@-sysunrecog@*/
00743     CLEANUP_HANDLER(sigchld_cancel, &pid, &oldtype);
00744 /*@=sysunrecog@*/
00745 
00746     pid = fork ();
00747     if (pid < (pid_t) 0) {              /* fork failed.  */
00748         goto out;
00749     } else if (pid == (pid_t) 0) {      /* Child. */
00750 
00751         /* Restore the signals.  */
00752         (void) sigaction (SIGINT, &rpmsigTbl_sigint->oact, NULL);
00753         (void) sigaction (SIGQUIT, &rpmsigTbl_sigquit->oact, NULL);
00754         (void) sigprocmask (SIG_SETMASK, &oldMask, NULL);
00755 
00756         /* Reset rpmsigTbl lock and refcnt. */
00757         INIT_LOCK ();
00758 
00759         (void) execve (argv[0], (char *const *) argv, environ);
00760         _exit (127);
00761     } else {                            /* Parent. */
00762         do {
00763             result = waitpid(pid, &status, 0);
00764         } while (result == (pid_t)-1 && errno == EINTR);
00765         if (result != pid)
00766             status = -1;
00767     }
00768 
00769     CLEANUP_RESET(0, oldtype);
00770 
00771     (void) DO_LOCK ();
00772     if ((SUB_REF (rpmsigTbl_sigchld) == 0 &&
00773         (rpmsqEnable(-SIGINT, NULL) < 0 || rpmsqEnable (-SIGQUIT, NULL) < 0))
00774       || sigprocmask (SIG_SETMASK, &oldMask, NULL) != 0)
00775     {
00776         status = -1;
00777     }
00778     goto out;
00779 
00780 out_restore_sigquit_and_sigint:
00781     (void) rpmsqEnable(-SIGQUIT, NULL);
00782 out_restore_sigint:
00783     (void) rpmsqEnable(-SIGINT, NULL);
00784 out:
00785     (void) DO_UNLOCK ();
00786     return status;
00787 }

Generated on Mon Nov 29 2010 05:18:48 for rpm by  doxygen 1.7.2