popen.c

   1 /*@ S-nail - a mail user agent derived from Berkeley Mail.
   2  *@ Handling of pipes, child processes, temporary files, file enwrapping.
   3  *
   4  * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
   5  * Copyright (c) 2012 - 2014 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
   6  */
   7 /*
   8  * Copyright (c) 1980, 1993
   9  * The Regents of the University of California.  All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *    This product includes software developed by the University of
  22  *    California, Berkeley and its contributors.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39
  40 #ifndef HAVE_AMALGAMATION
  41 # include "nail.h"
  42 #endif
  43
  44 #include <sys/wait.h>
  45
  46 #include <fcntl.h>
  47
  48 #define READ               0
  49 #define WRITE              1
  50
  51 #ifndef O_CLOEXEC
  52 # define _OUR_CLOEXEC
  53 # define O_CLOEXEC         0
  54 # define _SET_CLOEXEC(FD)  do fcntl((FD), F_SETFD, FD_CLOEXEC); while (0)
  55 #else
  56 # define _SET_CLOEXEC(FD)  do {} while (0)
  57 #endif
  58
  59 struct fp {
  60    FILE        *fp;
  61    struct fp   *link;
  62    char        *realfile;
  63    long        offset;
  64    int         omode;
  65    int         pipe;
  66    int         pid;
  67    enum {
  68       FP_RAW      = 0,
  69       FP_GZIP     = 1<<0,
  70       FP_XZ       = 1<<1,
  71       FP_BZIP2    = 1<<2,
  72       FP_IMAP     = 1<<3,
  73       FP_MAILDIR  = 1<<4,
  74       FP_MASK     = (1<<5) - 1,
  75       FP_READONLY = 1<<5
  76    }           compressed;
  77 };
  78
  79 struct child {
  80    int         pid;
  81    char        done;
  82    char        free;
  83    int         status;
  84    struct child *link;
  85 };
  86
  87 static struct fp     *fp_head;
  88 static struct child  *_popen_child;
  89
  90 static int           scan_mode(char const *mode, int *omode);
  91 static void          register_file(FILE *fp, int omode, int ispipe, int pid,
  92                         int compressed, char const *realfile, long offset);
  93 static enum okay     _compress(struct fp *fpp);
  94 static int           _decompress(int compression, int infd, int outfd);
  95 static enum okay     unregister_file(FILE *fp);
  96 static int           file_pid(FILE *fp);
  97
  98 /* Handle SIGCHLD */
  99 static void          _sigchld(int signo);
 100
 101 static int           wait_command(int pid);
 102 static struct child *findchild(int pid);
 103 static void          delchild(struct child *cp);
 104
 105 static int
 106 scan_mode(char const *mode, int *omode)
 107 {
 108    static struct {
 109       char const  mode[4];
 110       int         omode;
 111    } const maps[] = {
 112       {"r", O_RDONLY},
 113       {"w", O_WRONLY | O_CREAT | O_TRUNC},
 114       {"wx", O_WRONLY | O_CREAT | O_EXCL},
 115       {"a", O_WRONLY | O_APPEND | O_CREAT},
 116       {"a+", O_RDWR | O_APPEND},
 117       {"r+", O_RDWR},
 118       {"w+", O_RDWR | O_CREAT | O_EXCL}
 119    };
 120
 121    int i;
 122    NYD_ENTER;
 123
 124    for (i = 0; UICMP(z, i, <, NELEM(maps)); ++i)
 125       if (!strcmp(maps[i].mode, mode)) {
 126          *omode = maps[i].omode;
 127          i = 0;
 128          goto jleave;
 129       }
 130
 131    alert(tr(152, "Internal error: bad stdio open mode %s\n"), mode);
 132    errno = EINVAL;
 133    *omode = 0; /* (silence CC) */
 134    i = -1;
 135 jleave:
 136    NYD_LEAVE;
 137    return i;
 138 }
 139
 140 static void
 141 register_file(FILE *fp, int omode, int ispipe, int pid, int compressed,
 142    char const *realfile, long offset)
 143 {
 144    struct fp *fpp;
 145    NYD_ENTER;
 146
 147    fpp = smalloc(sizeof *fpp);
 148    fpp->fp = fp;
 149    fpp->omode = omode;
 150    fpp->pipe = ispipe;
 151    fpp->pid = pid;
 152    fpp->link = fp_head;
 153    fpp->compressed = compressed;
 154    fpp->realfile = (realfile != NULL) ? sstrdup(realfile) : NULL;
 155    fpp->offset = offset;
 156    fp_head = fpp;
 157    NYD_LEAVE;
 158 }
 159
 160 static enum okay
 161 _compress(struct fp *fpp)
 162 {
 163    char const *cmd[2];
 164    int outfd;
 165    enum okay rv;
 166    NYD_ENTER;
 167
 168    if (fpp->omode == O_RDONLY) {
 169       rv = OKAY;
 170       goto jleave;
 171    }
 172    rv = STOP;
 173
 174    fflush(fpp->fp);
 175    clearerr(fpp->fp);
 176    if (fseek(fpp->fp, fpp->offset, SEEK_SET) == -1)
 177       goto jleave;
 178
 179 #ifdef HAVE_IMAP
 180    if ((fpp->compressed & FP_MASK) == FP_IMAP) {
 181       rv = imap_append(fpp->realfile, fpp->fp);
 182       goto jleave;
 183    }
 184 #endif
 185    if ((fpp->compressed & FP_MASK) == FP_MAILDIR) {
 186       rv = maildir_append(fpp->realfile, fpp->fp);
 187       goto jleave;
 188    }
 189
 190    outfd = open(fpp->realfile, (fpp->omode | O_CREAT) & ~O_EXCL, 0666);
 191    if (outfd == -1) {
 192       fprintf(stderr, "Fatal: cannot create ");
 193       perror(fpp->realfile);
 194       goto jleave;
 195    }
 196    if (!(fpp->omode & O_APPEND))
 197       ftruncate(outfd, 0);
 198    switch (fpp->compressed & FP_MASK) {
 199    case FP_GZIP:
 200       cmd[0] = "gzip";  cmd[1] = "-c"; break;
 201    case FP_BZIP2:
 202       cmd[0] = "bzip2"; cmd[1] = "-c"; break;
 203    case FP_XZ:
 204       cmd[0] = "xz";    cmd[1] = "-c"; break;
 205    default:
 206       cmd[0] = "cat";   cmd[1] = NULL; break;
 207    }
 208    if (run_command(cmd[0], 0, fileno(fpp->fp), outfd, cmd[1], NULL, NULL) >= 0)
 209       rv = OKAY;
 210    close(outfd);
 211 jleave:
 212    NYD_LEAVE;
 213    return rv;
 214 }
 215
 216 static int
 217 _decompress(int compression, int infd, int outfd)
 218 {
 219    char const *cmd[2];
 220    int rv;
 221    NYD_ENTER;
 222
 223    switch (compression & FP_MASK) {
 224    case FP_GZIP:     cmd[0] = "gzip";  cmd[1] = "-cd"; break;
 225    case FP_BZIP2:    cmd[0] = "bzip2"; cmd[1] = "-cd"; break;
 226    case FP_XZ:       cmd[0] = "xz";    cmd[1] = "-cd"; break;
 227    default:          cmd[0] = "cat";   cmd[1] = NULL;  break;
 228    case FP_IMAP:
 229    case FP_MAILDIR:
 230       rv = 0;
 231       goto jleave;
 232    }
 233    rv = run_command(cmd[0], 0, infd, outfd, cmd[1], NULL, NULL);
 234 jleave:
 235    NYD_LEAVE;
 236    return rv;
 237 }
 238
 239 static enum okay
 240 unregister_file(FILE *fp)
 241 {
 242    struct fp **pp, *p;
 243    enum okay rv = OKAY;
 244    NYD_ENTER;
 245
 246    for (pp = &fp_head; (p = *pp) != NULL; pp = &p->link)
 247       if (p->fp == fp) {
 248          if ((p->compressed & FP_MASK) != FP_RAW) /* TODO ;} */
 249             rv = _compress(p);
 250          *pp = p->link;
 251          free(p);
 252          goto jleave;
 253       }
 254 #ifdef HAVE_DEBUG
 255    panic
 256 #else
 257    alert
 258 #endif
 259       (tr(153, "Invalid file pointer"));
 260    rv = STOP;
 261 jleave:
 262    NYD_LEAVE;
 263    return rv;
 264 }
 265
 266 static int
 267 file_pid(FILE *fp)
 268 {
 269    int rv;
 270    struct fp *p;
 271    NYD_ENTER;
 272
 273    rv = -1;
 274    for (p = fp_head; p; p = p->link)
 275       if (p->fp == fp) {
 276          rv = p->pid;
 277          break;
 278       }
 279    NYD_LEAVE;
 280    return rv;
 281 }
 282
 283 static void
 284 _sigchld(int signo)
 285 {
 286    int pid, status;
 287    struct child *cp;
 288    NYD_X; /* Signal handler */
 289    UNUSED(signo);
 290
 291    for (;;) {
 292       pid = (int)waitpid((pid_t)-1, &status, WNOHANG);
 293       if (pid <= 0) {
 294          if (pid == -1 && errno == EINTR)
 295             continue;
 296          break;
 297       }
 298       cp = findchild(pid);
 299       if (cp->free)
 300          delchild(cp);
 301       else {
 302          cp->done = 1;
 303          cp->status = status;
 304       }
 305    }
 306 }
 307
 308 static int
 309 wait_command(int pid)
 310 {
 311    int rv = 0;
 312    NYD_ENTER;
 313
 314    if (!wait_child(pid, NULL)) {
 315       if (ok_blook(bsdcompat) || ok_blook(bsdmsgs))
 316          fprintf(stderr, tr(154, "Fatal error in process.\n"));
 317       rv = -1;
 318    }
 319    NYD_LEAVE;
 320    return rv;
 321 }
 322
 323 static struct child *
 324 findchild(int pid)
 325 {
 326    struct child **cpp;
 327    NYD_ENTER;
 328
 329    for (cpp = &_popen_child; *cpp != NULL && (*cpp)->pid != pid;
 330          cpp = &(*cpp)->link)
 331       ;
 332    if (*cpp == NULL) {
 333       *cpp = smalloc(sizeof **cpp);
 334       (*cpp)->pid = pid;
 335       (*cpp)->done = (*cpp)->free = 0;
 336       (*cpp)->link = NULL;
 337    }
 338    NYD_LEAVE;
 339    return *cpp;
 340 }
 341
 342 static void
 343 delchild(struct child *cp)
 344 {
 345    struct child **cpp;
 346    NYD_ENTER;
 347
 348    for (cpp = &_popen_child; *cpp != cp; cpp = &(*cpp)->link)
 349       ;
 350    *cpp = cp->link;
 351    free(cp);
 352    NYD_LEAVE;
 353 }
 354
 355 FL void
 356 command_manager_start(void)
 357 {
 358    struct sigaction nact, oact;
 359    NYD_ENTER;
 360
 361    nact.sa_handler = &_sigchld;
 362    sigemptyset(&nact.sa_mask);
 363    nact.sa_flags = 0
 364 #ifdef SA_RESTART
 365          | SA_RESTART
 366 #endif
 367 #ifdef SA_NOCLDSTOP
 368          | SA_NOCLDSTOP
 369 #endif
 370          ;
 371    if (sigaction(SIGCHLD, &nact, &oact) != 0)
 372       panic("Cannot install signal handler for child process management");
 373    NYD_LEAVE;
 374 }
 375
 376 FL FILE *
 377 safe_fopen(char const *file, char const *oflags, int *xflags)
 378 {
 379    int osflags, fd;
 380    FILE *fp = NULL;
 381    NYD_ENTER;
 382
 383    if (scan_mode(oflags, &osflags) < 0)
 384       goto jleave;
 385    osflags |= O_CLOEXEC;
 386    if (xflags != NULL)
 387       *xflags = osflags;
 388
 389    if ((fd = open(file, osflags, 0666)) == -1)
 390       goto jleave;
 391    _SET_CLOEXEC(fd);
 392
 393    fp = fdopen(fd, oflags);
 394 jleave:
 395    NYD_LEAVE;
 396    return fp;
 397 }
 398
 399 FL FILE *
 400 Fopen(char const *file, char const *oflags)
 401 {
 402    FILE *fp;
 403    int osflags;
 404    NYD_ENTER;
 405
 406    if ((fp = safe_fopen(file, oflags, &osflags)) != NULL)
 407       register_file(fp, osflags, 0, 0, FP_RAW, NULL, 0L);
 408    NYD_LEAVE;
 409    return fp;
 410 }
 411
 412 FL FILE *
 413 Fdopen(int fd, char const *oflags)
 414 {
 415    FILE *fp;
 416    int osflags;
 417    NYD_ENTER;
 418
 419    scan_mode(oflags, &osflags);
 420    osflags |= O_CLOEXEC;
 421
 422    if ((fp = fdopen(fd, oflags)) != NULL)
 423       register_file(fp, osflags, 0, 0, FP_RAW, NULL, 0L);
 424    NYD_LEAVE;
 425    return fp;
 426 }
 427
 428 FL int
 429 Fclose(FILE *fp)
 430 {
 431    int i = 0;
 432    NYD_ENTER;
 433
 434    if (unregister_file(fp) == OKAY)
 435       i |= 1;
 436    if (fclose(fp) == 0)
 437       i |= 2;
 438    NYD_LEAVE;
 439    return (i == 3 ? 0 : EOF);
 440 }
 441
 442 FL FILE *
 443 Zopen(char const *file, char const *oflags, int *compression) /* FIXME MESS! */
 444 {
 445    FILE *rv = NULL;
 446    int _compression, osflags, mode, infd;
 447    enum oflags rof;
 448    long offset;
 449    enum protocol p;
 450    NYD_ENTER;
 451
 452    if (compression == NULL)
 453       compression = &_compression;
 454
 455    if (scan_mode(oflags, &osflags) < 0)
 456       goto jleave;
 457    rof = OF_RDWR | OF_UNLINK;
 458    if (osflags & O_APPEND)
 459       rof |= OF_APPEND;
 460    if (osflags == O_RDONLY) {
 461       mode = R_OK;
 462       *compression = FP_READONLY;
 463    } else {
 464       mode = R_OK | W_OK;
 465       *compression = 0;
 466    }
 467
 468    /* TODO ???? */
 469    if ((osflags & O_APPEND) && ((p = which_protocol(file)) == PROTO_IMAP ||
 470          p == PROTO_MAILDIR)) {
 471       *compression |= (p == PROTO_IMAP) ? FP_IMAP : FP_MAILDIR;
 472       osflags = O_RDWR | O_APPEND | O_CREAT;
 473       infd = -1;
 474    } else {
 475       char const *ext;
 476
 477       if ((ext = strrchr(file, '.')) != NULL) {
 478          if (!strcmp(ext, ".gz"))
 479             *compression |= FP_GZIP;
 480          else if (!strcmp(ext, ".xz"))
 481             *compression |= FP_XZ;
 482          else if (!strcmp(ext, ".bz2"))
 483             *compression |= FP_BZIP2;
 484          else
 485             goto jraw;
 486       } else {
 487 jraw:
 488          *compression |= FP_RAW;
 489          rv = Fopen(file, oflags);
 490          goto jleave;
 491       }
 492       if ((infd = open(file, (mode & W_OK) ? O_RDWR : O_RDONLY)) == -1 &&
 493             (!(osflags & O_CREAT) || errno != ENOENT))
 494          goto jleave;
 495    }
 496
 497    if ((rv = Ftmp(NULL, "zopen", rof, 0600)) == NULL) {
 498       perror(tr(167, "tmpfile"));
 499       goto jerr;
 500    }
 501    if (infd >= 0 || (*compression & FP_MASK) == FP_IMAP ||
 502          (*compression & FP_MASK) == FP_MAILDIR) {
 503       if (_decompress(*compression, infd, fileno(rv)) < 0) {
 504 jerr:
 505          if (rv != NULL)
 506             Fclose(rv);
 507          rv = NULL;
 508          if (infd >= 0)
 509             close(infd);
 510          goto jleave;
 511       }
 512    } else {
 513       if ((infd = creat(file, 0666)) == -1) {
 514          Fclose(rv);
 515          rv = NULL;
 516          goto jleave;
 517       }
 518    }
 519    if (infd >= 0)
 520       close(infd);
 521    fflush(rv);
 522
 523    if (!(osflags & O_APPEND))
 524       rewind(rv);
 525    if ((offset = ftell(rv)) == -1) {
 526       Fclose(rv);
 527       rv = NULL;
 528       goto jleave;
 529    }
 530    register_file(rv, osflags, 0, 0, *compression, file, offset);
 531 jleave:
 532    NYD_LEAVE;
 533    return rv;
 534 }
 535
 536 FL FILE *
 537 Ftmp(char **fn, char const *prefix, enum oflags oflags, int mode)
 538 {
 539    FILE *fp = NULL;
 540    char *cp_base, *cp;
 541    int fd;
 542    NYD_ENTER;
 543
 544    cp_base =
 545    cp = smalloc(strlen(tempdir) + 1 + sizeof("mail") + strlen(prefix) + 7 +1);
 546    cp = sstpcpy(cp, tempdir);
 547    *cp++ = '/';
 548    cp = sstpcpy(cp, "mail");
 549    if (*prefix) {
 550       *cp++ = '-';
 551       cp = sstpcpy(cp, prefix);
 552    }
 553    /* TODO Ftmp(): unroll our own creation loop with atoi(random()) */
 554    sstpcpy(cp, ".XXXXXX");
 555
 556    hold_all_sigs();
 557 #ifdef HAVE_MKSTEMP
 558    if ((fd = mkstemp(cp_base)) == -1)
 559       goto jfree;
 560    if (mode != (S_IRUSR | S_IWUSR) && fchmod(fd, mode) == -1)
 561       goto jclose;
 562    if (oflags & OF_APPEND) {
 563       int f;
 564
 565       if ((f = fcntl(fd, F_GETFL)) == -1 ||
 566             fcntl(fd, F_SETFL, f | O_APPEND) == -1) {
 567 jclose:
 568          close(fd);
 569          goto junlink;
 570       }
 571    }
 572    if (!(oflags & OF_REGISTER))
 573       fcntl(fd, F_SETFD, FD_CLOEXEC);
 574 #else
 575    if (mktemp(cp_base) == NULL)
 576       goto jfree;
 577    if ((fd = open(cp_base, O_CREAT | O_EXCL | O_RDWR | O_CLOEXEC |
 578          (oflags & OF_APPEND ? O_APPEND : 0), mode)) == -1)
 579       goto junlink;
 580    if (!(oflags & OF_REGISTER))
 581       _SET_CLOEXEC(fd);
 582 #endif
 583
 584    fp = (*((oflags & OF_REGISTER) ? &Fdopen : &fdopen))(fd,
 585          (oflags & OF_RDWR ? "w+" : "w"));
 586    if (fp == NULL || (oflags & OF_UNLINK)) {
 587 junlink:
 588       unlink(cp_base);
 589       goto jfree;
 590    }
 591
 592    if (fn != NULL)
 593       *fn = cp_base;
 594 jleave:
 595    if (fp == NULL || !(oflags & OF_HOLDSIGS))
 596       rele_all_sigs();
 597    NYD_LEAVE;
 598    return fp;
 599 jfree:
 600    if ((cp = cp_base) != NULL)
 601       free(cp);
 602    goto jleave;
 603 }
 604
 605 FL void
 606 Ftmp_release(char **fn)
 607 {
 608    char *cp;
 609    NYD_ENTER;
 610
 611    cp = *fn;
 612    *fn = NULL;
 613    if (cp != NULL) {
 614       unlink(cp);
 615       rele_all_sigs();
 616       free(cp);
 617    }
 618    NYD_LEAVE;
 619 }
 620
 621 FL void
 622 Ftmp_free(char **fn)
 623 {
 624    char *cp;
 625    NYD_ENTER;
 626
 627    cp = *fn;
 628    *fn = NULL;
 629    if (cp != NULL)
 630       free(cp);
 631    NYD_LEAVE;
 632 }
 633
 634 FL bool_t
 635 pipe_cloexec(int fd[2])
 636 {
 637    bool_t rv = FAL0;
 638    NYD_ENTER;
 639
 640 #ifdef HAVE_PIPE2
 641    if (pipe2(fd, O_CLOEXEC) == -1)
 642       goto jleave;
 643 #else
 644    if (pipe(fd) == -1)
 645       goto jleave;
 646    fcntl(fd[0], F_SETFD, FD_CLOEXEC);
 647    fcntl(fd[1], F_SETFD, FD_CLOEXEC);
 648 #endif
 649    rv = TRU1;
 650 jleave:
 651    NYD_LEAVE;
 652    return rv;
 653 }
 654
 655 FL FILE *
 656 Popen(char const *cmd, char const *mode, char const *sh, int newfd1)
 657 {
 658    int p[2], myside, hisside, fd0, fd1, pid;
 659    char mod[2] = {'0', '\0'};
 660    sigset_t nset;
 661    FILE *rv = NULL;
 662    NYD_ENTER;
 663
 664    if (!pipe_cloexec(p))
 665       goto jleave;
 666
 667    if (*mode == 'r') {
 668       myside = p[READ];
 669       fd0 = -1;
 670       hisside = fd1 = p[WRITE];
 671       mod[0] = *mode;
 672    } else if (*mode == 'W') {
 673       myside = p[WRITE];
 674       hisside = fd0 = p[READ];
 675       fd1 = newfd1;
 676       mod[0] = 'w';
 677    } else {
 678       myside = p[WRITE];
 679       hisside = fd0 = p[READ];
 680       fd1 = -1;
 681       mod[0] = 'w';
 682    }
 683    sigemptyset(&nset);
 684    if (sh == NULL) {
 685       pid = start_command(cmd, &nset, fd0, fd1, NULL, NULL, NULL);
 686    } else {
 687       pid = start_command(sh, &nset, fd0, fd1, "-c", cmd, NULL);
 688    }
 689    if (pid < 0) {
 690       close(p[READ]);
 691       close(p[WRITE]);
 692       goto jleave;
 693    }
 694    close(hisside);
 695    if ((rv = fdopen(myside, mod)) != NULL)
 696       register_file(rv, 0, 1, pid, FP_RAW, NULL, 0L);
 697 jleave:
 698    NYD_LEAVE;
 699    return rv;
 700 }
 701
 702 FL bool_t
 703 Pclose(FILE *ptr, bool_t dowait)
 704 {
 705    sigset_t nset, oset;
 706    int pid;
 707    bool_t rv = FAL0;
 708    NYD_ENTER;
 709
 710    pid = file_pid(ptr);
 711    if (pid < 0)
 712       goto jleave;
 713    unregister_file(ptr);
 714    fclose(ptr);
 715    if (dowait) {
 716       sigemptyset(&nset);
 717       sigaddset(&nset, SIGINT);
 718       sigaddset(&nset, SIGHUP);
 719       sigprocmask(SIG_BLOCK, &nset, &oset);
 720       rv = wait_child(pid, NULL);
 721       sigprocmask(SIG_SETMASK, &oset, NULL);
 722    } else {
 723       free_child(pid);
 724       rv = TRU1;
 725    }
 726 jleave:
 727    NYD_LEAVE;
 728    return rv;
 729 }
 730
 731 FL void
 732 close_all_files(void)
 733 {
 734    NYD_ENTER;
 735    while (fp_head != NULL)
 736       if (fp_head->pipe)
 737          Pclose(fp_head->fp, TRU1);
 738       else
 739          Fclose(fp_head->fp);
 740    NYD_LEAVE;
 741 }
 742
 743 FL int
 744 run_command(char const *cmd, sigset_t *mask, int infd, int outfd,
 745    char const *a0, char const *a1, char const *a2)
 746 {
 747    int rv;
 748    NYD_ENTER;
 749
 750    if ((rv = start_command(cmd, mask, infd, outfd, a0, a1, a2)) < 0)
 751       rv = -1;
 752    else
 753       rv = wait_command(rv);
 754    NYD_LEAVE;
 755    return rv;
 756 }
 757
 758 FL int
 759 start_command(char const *cmd, sigset_t *mask, int infd, int outfd,
 760    char const *a0, char const *a1, char const *a2)
 761 {
 762    int rv;
 763    NYD_ENTER;
 764
 765    if ((rv = fork()) == -1) {
 766       perror("fork");
 767       rv = -1;
 768    } else if (rv == 0) {
 769       char *argv[100];
 770       int i = getrawlist(cmd, strlen(cmd), argv, NELEM(argv), 0);
 771
 772       if ((argv[i++] = UNCONST(a0)) != NULL &&
 773           (argv[i++] = UNCONST(a1)) != NULL &&
 774           (argv[i++] = UNCONST(a2)) != NULL)
 775          argv[i] = NULL;
 776       prepare_child(mask, infd, outfd);
 777       execvp(argv[0], argv);
 778       perror(argv[0]);
 779       _exit(1);
 780    }
 781    NYD_LEAVE;
 782    return rv;
 783 }
 784
 785 FL void
 786 prepare_child(sigset_t *nset, int infd, int outfd)
 787 {
 788    int i;
 789    sigset_t fset;
 790    NYD_ENTER;
 791
 792    /* All file descriptors other than 0, 1, and 2 are supposed to be cloexec */
 793    if (infd >= 0)
 794       dup2(infd, 0);
 795    if (outfd >= 0)
 796       dup2(outfd, 1);
 797
 798    if (nset) {
 799       for (i = 1; i < NSIG; ++i)
 800          if (sigismember(nset, i))
 801             safe_signal(i, SIG_IGN);
 802       if (!sigismember(nset, SIGINT))
 803          safe_signal(SIGINT, SIG_DFL);
 804    }
 805
 806    sigemptyset(&fset);
 807    sigprocmask(SIG_SETMASK, &fset, NULL);
 808    NYD_LEAVE;
 809 }
 810
 811 FL void
 812 free_child(int pid)
 813 {
 814    sigset_t nset, oset;
 815    struct child *cp;
 816    NYD_ENTER;
 817
 818    sigemptyset(&nset);
 819    sigaddset(&nset, SIGCHLD);
 820    sigprocmask(SIG_BLOCK, &nset, &oset);
 821
 822    cp = findchild(pid);
 823    if (cp->done)
 824       delchild(cp);
 825    else
 826       cp->free = 1;
 827
 828    sigprocmask(SIG_SETMASK, &oset, NULL);
 829    NYD_LEAVE;
 830 }
 831
 832 FL bool_t
 833 wait_child(int pid, int *wait_status)
 834 {
 835    sigset_t nset, oset;
 836    struct child *cp;
 837    int ws;
 838    bool_t rv;
 839    NYD_ENTER;
 840
 841    sigemptyset(&nset);
 842    sigaddset(&nset, SIGCHLD);
 843    sigprocmask(SIG_BLOCK, &nset, &oset);
 844
 845    cp = findchild(pid);
 846    while (!cp->done)
 847       sigsuspend(&oset);
 848    ws = cp->status;
 849    delchild(cp);
 850
 851    sigprocmask(SIG_SETMASK, &oset, NULL);
 852
 853    if (wait_status != NULL)
 854       *wait_status = ws;
 855    rv = (WIFEXITED(ws) && WEXITSTATUS(ws) == 0);
 856    NYD_LEAVE;
 857    return rv;
 858 }
 859
 860 #ifdef _OUR_CLOEXEC
 861 # undef O_CLOEXEC
 862 # undef _OUR_CLOEXEC
 863 #endif
 864 #undef _SET_CLOEXEC
 865
 866 /* vim:set fenc=utf-8:s-it-mode */