xio-progcall.c

   1 /* source: xio-progcall.c */
   2 /* Copyright Gerhard Rieger and contributors (see file CHANGES) */
   3 /* Published under the GNU General Public License V.2, see file COPYING */
   4
   5 /* this file contains common code dealing with program calls (exec, system) */
   6
   7 #include "xiosysincludes.h"
   8 #include "xioopen.h"
   9
  10 #include "xio-process.h"
  11 #include "xio-named.h"
  12 #include "xio-progcall.h"
  13
  14 #include "xio-socket.h"
  15
  16
  17 /* these options are used by address pty too */
  18 #if HAVE_OPENPTY
  19 const struct optdesc opt_openpty = { "openpty",   NULL, OPT_OPENPTY,     GROUP_PTY,   PH_BIGEN, TYPE_BOOL,      OFUNC_SPEC };
  20 #endif /* HAVE_OPENPTY */
  21 #if HAVE_DEV_PTMX || HAVE_DEV_PTC
  22 const struct optdesc opt_ptmx    = { "ptmx",      NULL, OPT_PTMX,        GROUP_PTY,   PH_BIGEN, TYPE_BOOL,      OFUNC_SPEC };
  23 #endif
  24 const struct optdesc opt_sitout_eio = { "sitout-eio", NULL, OPT_SITOUT_EIO, GROUP_PTY, PH_OFFSET, TYPE_TIMEVAL, OFUNC_OFFSET, XIO_OFFSETOF(para.exec.sitout_eio), XIO_SIZEOF(para.exec.sitout_eio) };
  25
  26 #if WITH_EXEC || WITH_SYSTEM
  27
  28 #define MAXPTYNAMELEN 64
  29
  30 const struct optdesc opt_fdin    = { "fdin",      NULL, OPT_FDIN,        GROUP_FORK,   PH_PASTBIGEN,   TYPE_USHORT,     OFUNC_SPEC };
  31 const struct optdesc opt_fdout   = { "fdout",     NULL, OPT_FDOUT,       GROUP_FORK,   PH_PASTBIGEN,   TYPE_USHORT,     OFUNC_SPEC };
  32 const struct optdesc opt_path    = { "path",      NULL, OPT_PATH,        GROUP_EXEC,   PH_PREEXEC,     TYPE_STRING,     OFUNC_SPEC };
  33 const struct optdesc opt_pipes   = { "pipes",     NULL, OPT_PIPES,       GROUP_FORK,   PH_BIGEN,       TYPE_BOOL,       OFUNC_SPEC };
  34 #if HAVE_PTY
  35 const struct optdesc opt_pty     = { "pty",       NULL, OPT_PTY,         GROUP_FORK,   PH_BIGEN, TYPE_BOOL,     OFUNC_SPEC };
  36 #endif
  37 const struct optdesc opt_stderr  = { "stderr",    NULL, OPT_STDERR,      GROUP_FORK,   PH_PASTFORK,        TYPE_BOOL,   OFUNC_SPEC };
  38 const struct optdesc opt_nofork  = { "nofork",    NULL, OPT_NOFORK,      GROUP_FORK,   PH_BIGEN,       TYPE_BOOL,       OFUNC_SPEC };
  39 const struct optdesc opt_sighup  = { "sighup",    NULL, OPT_SIGHUP,      GROUP_PARENT, PH_LATE,        TYPE_CONST,      OFUNC_SIGNAL, SIGHUP };
  40 const struct optdesc opt_sigint  = { "sigint",    NULL, OPT_SIGINT,      GROUP_PARENT, PH_LATE,        TYPE_CONST,      OFUNC_SIGNAL, SIGINT };
  41 const struct optdesc opt_sigquit = { "sigquit",   NULL, OPT_SIGQUIT,     GROUP_PARENT, PH_LATE,        TYPE_CONST,      OFUNC_SIGNAL, SIGQUIT };
  42
  43
  44 /* fork for exec/system, but return before exec'ing.
  45    return=0: is child process
  46    return>0: is parent process
  47    return<0: error occurred, assume parent process and no child exists !!!
  48  */
  49 int _xioopen_foxec(int xioflags,        /* XIO_RDONLY etc. */
  50                 struct single *sfd,
  51                    groups_t groups,
  52                    struct opt **optsp,  /* in: opts; out: opts for parent/child */
  53                    int *duptostderr     /* out: redirect stderr to output fd */
  54                 ) {
  55    struct opt *opts;            /* common options */
  56    struct opt *popts = NULL;    /* parent options */
  57    struct opt *copts;           /* child options */
  58    int numleft;
  59    int d, sv[2], rdpip[2], wrpip[2];
  60    int rw = (xioflags & XIO_ACCMODE);
  61    bool usepipes = false;
  62 #if HAVE_PTY
  63    int ptyfd = -1, ttyfd = -1;
  64    bool usebestpty = false;     /* use the best available way to open pty */
  65 #if defined(HAVE_DEV_PTMX) || defined(HAVE_DEV_PTC)
  66    bool useptmx = false;        /* use /dev/ptmx or equivalent */
  67 #endif
  68 #if HAVE_OPENPTY
  69    bool useopenpty = false;     /* try only openpty */
  70 #endif  /* HAVE_OPENPTY */
  71    bool usepty = false;         /* any of the pty options is selected */
  72    char ptyname[MAXPTYNAMELEN];
  73 #endif /* HAVE_PTY */
  74    pid_t pid = 0;       /* mostly int */
  75    short fdi = 0, fdo = 1;
  76    short result;
  77    bool withstderr = false;
  78    bool nofork = false;
  79    bool withfork;
  80    char *tn = NULL;
  81    int trigger[2];      /* [0] watched by parent, [1] closed by child when ready */
  82
  83    opts = *optsp;
  84    if (applyopts_single(sfd, opts, PH_INIT) < 0)  return -1;
  85    applyopts2(sfd, -1, opts, PH_INIT, PH_EARLY);
  86
  87    retropt_bool(opts, OPT_NOFORK, &nofork);
  88    withfork = !nofork;
  89
  90    retropt_bool(opts, OPT_PIPES, &usepipes);
  91 #if HAVE_PTY
  92    retropt_bool(opts, OPT_PTY, &usebestpty);
  93 #if HAVE_OPENPTY
  94    retropt_bool(opts, OPT_OPENPTY, &useopenpty);
  95 #endif
  96 #if defined(HAVE_DEV_PTMX) || defined(HAVE_DEV_PTC)
  97    retropt_bool(opts, OPT_PTMX, &useptmx);
  98 #endif
  99    usepty = (usebestpty
 100 #if HAVE_OPENPTY
 101              || useopenpty
 102 #endif
 103 #if defined(HAVE_DEV_PTMX) || defined(HAVE_DEV_PTC)
 104              || useptmx
 105 #endif
 106              );
 107    if (usepipes && usepty) {
 108       Warn("_xioopen_foxec(): options \"pipes\" and \"pty\" must not be specified together; ignoring \"pipes\"");
 109       usepipes = false;
 110    }
 111 #endif /* HAVE_PTY */
 112
 113    if (retropt_ushort(opts, OPT_FDIN,  (unsigned short *)&fdi) >= 0) {
 114       if ((xioflags&XIO_ACCMODE) == XIO_RDONLY) {
 115          Error("_xioopen_foxec(): option fdin is useless in read-only mode");
 116       }
 117    }
 118    if (retropt_ushort(opts, OPT_FDOUT, (unsigned short *)&fdo) >= 0) {
 119       if ((xioflags&XIO_ACCMODE) == XIO_WRONLY) {
 120          Error("_xioopen_foxec(): option fdout is useless in write-only mode");
 121       }
 122    }
 123
 124    if (withfork) {
 125       if (!(xioflags&XIO_MAYCHILD)) {
 126          Error("cannot fork off child process here");
 127          /*!! free something */
 128          return -1;
 129       }
 130       sfd->flags |= XIO_DOESCHILD;
 131
 132 #if HAVE_PTY
 133       Notice2("forking off child, using %s for %s",
 134             &("socket\0\0pipes\0\0\0pty\0\0\0\0\0"[(usepipes<<3)|(usepty<<4)]),
 135               ddirection[rw]);
 136 #else
 137       Notice2("forking off child, using %s for %s",
 138               &("socket\0\0pipes\0\0\0"[(usepipes<<3)]),
 139               ddirection[rw]);
 140 #endif /* HAVE_PTY */
 141    }
 142    applyopts(sfd, -1, opts, PH_PREBIGEN);
 143
 144    if (!withfork) {
 145       /*0 struct single *stream1, *stream2;*/
 146
 147       if (!(xioflags & XIO_MAYEXEC /* means exec+nofork */)) {
 148          Error("option nofork is not allowed here");
 149          /*!! free something */
 150          return -1;
 151       }
 152       sfd->flags |= XIO_DOESEXEC;
 153
 154       /* Only one process, no parent,child */
 155       if ((copts = moveopts(opts, GROUP_ALL)) == NULL) {
 156          /*!! free something */
 157          return -1;
 158       }
 159
 160 #if 0 /*!! */
 161       if (sock1->tag == XIO_TAG_DUAL) {
 162          stream1 = &sock1->dual.stream[0]->stream;
 163          stream2 = &sock1->dual.stream[1]->stream;
 164       } else {
 165          stream1 = &sock1->stream;
 166          stream2 = &sock1->stream;
 167       }
 168       if (stream1->dtype == DATA_READLINE || stream2->dtype == DATA_READLINE ||
 169           stream1->dtype == DATA_OPENSSL  || stream2->dtype == DATA_OPENSSL
 170           ) {
 171          Error("with option nofork, openssl and readline in address1 do not work");
 172       }
 173       if (stream1->lineterm != LINETERM_RAW ||
 174           stream2->lineterm != LINETERM_RAW ||
 175           stream1->ignoreeof || stream2->ignoreeof) {
 176          Warn("due to option nofork, address1 options for lineterm and igoreeof do not apply");
 177       }
 178 #endif
 179
 180       /* remember: fdin is the fd where the sub program reads from, thus it is
 181          sock0[]'s read fd */
 182       /*! problem: when fdi==WRFD(sock[0]) or fdo==RDFD(sock[0]) */
 183       if (rw != XIO_WRONLY) {
 184          if (XIO_GETWRFD(sock[0]/*!!*/) == fdo) {
 185             if (Fcntl_l(fdo, F_SETFD, 0) < 0) {
 186                Warn2("fcntl(%d, F_SETFD, 0): %s", fdo, strerror(errno));
 187             }
 188          } else {
 189             /* make sure that the internal diagnostic socket pair fds do not conflict
 190                with our choices */
 191             diag_reserve_fd(fdo);
 192             if (Dup2(XIO_GETWRFD(sock[0]), fdo) < 0) {
 193                Error3("dup2(%d, %d): %s",
 194                       XIO_GETWRFD(sock[0]), fdo, strerror(errno));
 195             }
 196          }
 197          /*0 Info2("dup2(%d, %d)", XIO_GETRDFD(sock[0]), fdi);*/
 198       }
 199       if (rw != XIO_RDONLY) {
 200          if (XIO_GETRDFD(sock[0]) == fdi) {
 201             if (Fcntl_l(fdi, F_SETFD, 0) < 0) {
 202                Warn2("fcntl(%d, F_SETFD, 0): %s", fdi, strerror(errno));
 203             }
 204          } else {
 205             /* make sure that the internal diagnostic socket pair fds do not conflict
 206                with our choices */
 207             diag_reserve_fd(fdi);
 208             if (Dup2(XIO_GETRDFD(sock[0]), fdi) < 0) {
 209                Error3("dup2(%d, %d): %s)",
 210                       XIO_GETRDFD(sock[0]), fdi, strerror(errno));
 211             }
 212             /*0 Info2("dup2(%d, %d)", XIO_GETWRFD(sock[0]), fdo);*/
 213          }
 214       }
 215       /* !withfork */
 216    } else /* withfork */
 217 #if HAVE_PTY
 218    if (usepty) {
 219
 220 #if defined(HAVE_DEV_PTMX)
 221 #  define PTMX "/dev/ptmx"      /* Linux */
 222 #elif HAVE_DEV_PTC
 223 #  define PTMX "/dev/ptc"       /* AIX 4.3.3 */
 224 #endif
 225       sfd->dtype = XIODATA_PTY;
 226 #if HAVE_DEV_PTMX || HAVE_DEV_PTC
 227       if (usebestpty || useptmx) {
 228          if ((ptyfd = Open(PTMX, O_RDWR|O_NOCTTY, 0620)) < 0) {
 229             Warn1("open(\""PTMX"\", O_RDWR|O_NOCTTY, 0620): %s",
 230                   strerror(errno));
 231             /*!*/
 232          } else {
 233             /*0 Info2("open(\"%s\", O_RDWR|O_NOCTTY, 0620) -> %d", PTMX, ptyfd);*/
 234          }
 235          if (ptyfd >= 0 && ttyfd < 0) {
 236             /* we used PTMX before forking */
 237             extern char *ptsname(int);
 238
 239 #if HAVE_PROTOTYPE_LIB_ptsname  /* AIX, not Linux */
 240             if ((tn = Ptsname(ptyfd)) == NULL) {
 241                Warn2("ptsname(%d): %s", ptyfd, strerror(errno));
 242             }
 243 #endif /* HAVE_PROTOTYPE_LIB_ptsname */
 244             if (tn == NULL) {
 245                if ((tn = Ttyname(ptyfd)) == NULL) {
 246                   Error2("ttyname(%d): %s", ptyfd, strerror(errno));
 247                }
 248             }
 249             ptyname[0] = '\0'; strncat(ptyname, tn, MAXPTYNAMELEN-1);
 250 #if HAVE_GRANTPT        /* AIX, not Linux */
 251             if (Grantpt(ptyfd)/*!*/ < 0) {
 252                Warn2("grantpt(%d): %s", ptyfd, strerror(errno));
 253             }
 254 #endif /* HAVE_GRANTPT */
 255 #if HAVE_UNLOCKPT
 256             if (Unlockpt(ptyfd)/*!*/ < 0) {
 257                Warn2("unlockpt(%d): %s", ptyfd, strerror(errno));
 258             }
 259 #endif /* HAVE_UNLOCKPT */
 260          }
 261       }
 262 #endif /* HAVE_DEV_PTMX || HAVE_DEV_PTC */
 263 #if HAVE_OPENPTY
 264       if (ptyfd < 0) {
 265          int result;
 266          if ((result = Openpty(&ptyfd, &ttyfd, ptyname, NULL, NULL)) < 0) {
 267             Error4("openpty(%p, %p, %p, NULL, NULL): %s",
 268                    &ptyfd, &ttyfd, ptyname, strerror(errno));
 269             return -1;
 270          }
 271       }
 272 #endif /* HAVE_OPENPTY */
 273       /* withfork use_pty */
 274       if ((copts = moveopts(opts, GROUP_TERMIOS|GROUP_FORK|GROUP_EXEC|GROUP_PROCESS|GROUP_NAMED)) == NULL) {
 275          return -1;
 276       }
 277       popts = opts;
 278       applyopts_cloexec(ptyfd, popts);/*!*/
 279       /* exec:...,pty did not kill child process under some circumstances */
 280       if (sfd->howtoend == END_UNSPEC) {
 281          sfd->howtoend = END_CLOSE_KILL;
 282       }
 283
 284       /* this for parent, was after fork */
 285       applyopts(sfd, ptyfd, popts, PH_FD);
 286       sfd->fd = ptyfd;
 287
 288       /* end withfork, use_pty */
 289    } else /* end withfork, use_pty */
 290 #endif /* HAVE_PTY */
 291
 292    if (usepipes) {
 293       /* withfork usepipes */
 294       struct opt *popts2 = NULL;
 295
 296       if (rw == XIO_RDWR)
 297          sfd->dtype = XIODATA_2PIPE;
 298       if (rw != XIO_WRONLY) {
 299          if (Pipe(rdpip) < 0) {
 300             Error2("pipe(%p): %s", rdpip, strerror(errno));
 301             return -1;
 302          }
 303       }
 304       /*0 Info2("pipe({%d,%d})", rdpip[0], rdpip[1]);*/
 305       /* rdpip[0]: read by socat; rdpip[1]: write by child */
 306
 307       /* withfork usepipes */
 308       if ((copts = moveopts(opts, GROUP_FORK|GROUP_EXEC|GROUP_PROCESS))
 309           == NULL) {
 310          return -1;
 311       }
 312       popts = opts;
 313       if (sfd->dtype == XIODATA_2PIPE)
 314          popts2 = copyopts(popts, GROUP_ALL);
 315
 316       if (rw != XIO_WRONLY) {
 317          applyopts_cloexec(rdpip[0], popts);
 318          applyopts(sfd, rdpip[0], popts, PH_FD);
 319          applyopts(sfd, rdpip[1], copts, PH_FD);
 320       }
 321
 322       if (rw != XIO_RDONLY) {
 323          if (Pipe(wrpip) < 0) {
 324             Error2("pipe(%p): %s", wrpip, strerror(errno));
 325             return -1;
 326          }
 327       }
 328
 329       /* wrpip[1]: write by socat; wrpip[0]: read by child */
 330       if (rw != XIO_RDONLY) {
 331          applyopts_cloexec(wrpip[1], popts);
 332          if (sfd->dtype == XIODATA_2PIPE)
 333             applyopts(NULL, wrpip[1], popts2, PH_FD);
 334          else
 335             applyopts(NULL, wrpip[1], popts, PH_FD);
 336          applyopts(NULL, wrpip[0], copts, PH_FD);
 337       }
 338       if (sfd->howtoend == END_UNSPEC) {
 339          sfd->howtoend = END_CLOSE_KILL;
 340       }
 341
 342       /* this for parent, was after fork */
 343       switch (rw) {
 344       case XIO_RDONLY: sfd->fd = rdpip[0]; break;
 345       case XIO_WRONLY: sfd->fd = wrpip[1]; break;
 346       case XIO_RDWR:   sfd->fd = rdpip[0];
 347          sfd->para.exec.fdout = wrpip[1];
 348          break;
 349       }
 350       applyopts(sfd, -1, popts, PH_FD);
 351       applyopts(sfd, -1, popts, PH_LATE);
 352       if (applyopts_single(sfd, popts, PH_LATE) < 0)
 353          return -1;
 354
 355       /* end withfork, use_pipes */
 356    } else {
 357       /* withfork, socketpair */
 358
 359       d = AF_UNIX;
 360       retropt_int(opts, OPT_PROTOCOL_FAMILY, &d);
 361       result = xiosocketpair(opts, d, SOCK_STREAM, 0, sv);
 362       if (result < 0) {
 363          return -1;
 364       }
 365
 366       /* withfork socketpair */
 367       if ((copts = moveopts(opts, GROUP_FORK|GROUP_EXEC|GROUP_PROCESS)) == NULL) {
 368          return -1;
 369       }
 370       popts = opts;
 371       applyopts(sfd, sv[0], copts, PH_PASTSOCKET);
 372       applyopts(sfd, sv[1], popts, PH_PASTSOCKET);
 373
 374       applyopts_cloexec(sv[0], copts);
 375       applyopts(sfd, sv[0], copts, PH_FD);
 376       applyopts(sfd, sv[1], popts, PH_FD);
 377
 378       applyopts(sfd, sv[0], copts, PH_PREBIND);
 379       applyopts(sfd, sv[0], copts, PH_BIND);
 380       applyopts(sfd, sv[0], copts, PH_PASTBIND);
 381       applyopts(sfd, sv[1], popts, PH_PREBIND);
 382       applyopts(sfd, sv[1], popts, PH_BIND);
 383       applyopts(sfd, sv[1], popts, PH_PASTBIND);
 384
 385       if (sfd->howtoend == END_UNSPEC) {
 386          sfd->howtoend = END_SHUTDOWN_KILL;
 387       }
 388
 389       /* this for parent, was after fork */
 390       sfd->fd = sv[0];
 391       applyopts(sfd, -1, popts, PH_FD);
 392       /* end withfork, socketpair */
 393    }
 394    retropt_bool(copts, OPT_STDERR, &withstderr);
 395
 396    xiosetchilddied();   /* set SIGCHLD handler */
 397
 398    if (withfork) {
 399       Socketpair(PF_UNIX, SOCK_STREAM, 0, trigger);
 400       pid = xio_fork(true, E_ERROR, 0);
 401       if (pid < 0) {
 402          return -1;
 403       }
 404    }
 405    if (!withfork || pid == 0) { /* in single process, or in child */
 406       applyopts_optgroup(sfd, -1, copts, GROUP_PROCESS);
 407       if (withfork) {
 408          Close(trigger[0]);     /* in child: not needed here */
 409          /* The child should have default handling for SIGCHLD. */
 410          /* In particular, it's not defined whether ignoring SIGCHLD is inheritable. */
 411          if (Signal(SIGCHLD, SIG_DFL) == SIG_ERR) {
 412             Warn1("signal(SIGCHLD, SIG_DFL): %s", strerror(errno));
 413          }
 414
 415 #if HAVE_PTY
 416          if (usepty) {
 417             applyopts_named(tn, copts, PH_PREOPEN);
 418             applyopts_named(tn, copts, PH_EARLY);
 419             applyopts_named(tn, copts, PH_FD);
 420
 421            if (ttyfd < 0) {
 422             if ((ttyfd = Open(tn, O_RDWR|O_NOCTTY, 0620)) < 0) {
 423                Warn2("open(\"%s\", O_RDWR|O_NOCTTY, 0620): %s", tn, strerror(errno));
 424             } else {
 425                /*0 Info2("open(\"%s\", O_RDWR|O_NOCTTY, 0620) -> %d", tn, ttyfd);*/
 426             }
 427            } else {
 428               if ((tn = Ttyname(ttyfd)) == NULL) {
 429                  Warn2("ttyname(%d): %s", ttyfd, strerror(errno));
 430               }
 431            }
 432
 433 #ifdef I_PUSH
 434             /* Linux: I_PUSH def'd; pty: ioctl(, I_FIND, ...) -> -1 EINVAL */
 435             /* AIX:   I_PUSH def'd; pty: ioctl(, I_FIND, ...) -> 1 */
 436             /* SunOS: I_PUSH def'd; pty: ioctl(, I_FIND, ...) -> 0 */
 437             /* HP-UX: I_PUSH def'd; pty: ioctl(, I_FIND, ...) -> 0 */
 438             if (Ioctl(ttyfd, I_FIND, "ldterm\0") == 0) {
 439                Ioctl(ttyfd, I_PUSH, "ptem\0\0\0");      /* 0 */ /* padding for AdressSanitizer */
 440                Ioctl(ttyfd, I_PUSH, "ldterm\0");        /* 0 */
 441                Ioctl(ttyfd, I_PUSH, "ttcompat");        /* HP-UX: -1 */
 442             }
 443 #endif
 444
 445             /* this for child, was after fork */
 446             applyopts(sfd, ttyfd, copts, PH_FD);
 447
 448             Info1("opened pseudo terminal %s", tn);
 449             Close(ptyfd);
 450             if (rw != XIO_RDONLY && fdi != ttyfd) {
 451                /* make sure that the internal diagnostic socket pair fds do not conflict
 452                   with our choices */
 453                diag_reserve_fd(fdi);
 454                if (Dup2(ttyfd, fdi) < 0) {
 455                   Error3("dup2(%d, %d): %s", ttyfd, fdi, strerror(errno));
 456                   return -1; }
 457                /*0 Info2("dup2(%d, %d)", ttyfd, fdi);*/
 458             }
 459             if (rw != XIO_WRONLY && fdo != ttyfd) {
 460                /* make sure that the internal diagnostic socket pair fds do not conflict
 461                   with our choices */
 462                diag_reserve_fd(fdo);
 463                if (Dup2(ttyfd, fdo) < 0) {
 464                   Error3("dup2(%d, %d): %s", ttyfd, fdo, strerror(errno));
 465                   return -1; }
 466                /*0 Info2("dup2(%d, %d)", ttyfd, fdo);*/
 467             }
 468             if ((rw == XIO_RDONLY || fdi != ttyfd) &&
 469                 (rw == XIO_WRONLY || fdo != ttyfd)) {
 470                applyopts_cloexec(ttyfd, copts);
 471             }
 472
 473             applyopts(sfd, ttyfd, copts, PH_LATE);
 474             applyopts(sfd, ttyfd, copts, PH_LATE2);
 475          } else
 476 #endif /* HAVE_PTY */
 477             if (usepipes) {
 478                /* we might have a temporary conflict between what FDs are
 479                   currently allocated, and which are to be used. We try to find
 480                   a graceful solution via temporary descriptors */
 481                int tmpi, tmpo;
 482
 483                if (rw != XIO_WRONLY)  Close(rdpip[0]);
 484                if (rw != XIO_RDONLY)  Close(wrpip[1]);
 485                if (fdi == rdpip[1]) {   /* a conflict here */
 486                   if ((tmpi = Dup(wrpip[0])) < 0) {
 487                      Error2("dup(%d): %s", wrpip[0], strerror(errno));
 488                      return -1;
 489                   }
 490                   /*0 Info2("dup(%d) -> %d", wrpip[0], tmpi);*/
 491                   rdpip[1] = tmpi;
 492                }
 493                if (fdo == wrpip[0]) {   /* a conflict here */
 494                   if ((tmpo = Dup(rdpip[1])) < 0) {
 495                      Error2("dup(%d): %s", rdpip[1], strerror(errno));
 496                      return -1;
 497                   }
 498                   /*0 Info2("dup(%d) -> %d", rdpip[1], tmpo);*/
 499                   wrpip[0] = tmpo;
 500                }
 501
 502                if (rw != XIO_WRONLY && rdpip[1] != fdo) {
 503                   /* make sure that the internal diagnostic socket pair fds do not conflict
 504                      with our choices */
 505                   diag_reserve_fd(fdo);
 506                   if (Dup2(rdpip[1], fdo) < 0) {
 507                      Error3("dup2(%d, %d): %s", rdpip[1], fdo, strerror(errno));
 508                      return -1;
 509                   }
 510                   Close(rdpip[1]);
 511                }
 512                if (rw != XIO_RDONLY && wrpip[0] != fdi) {
 513                   /* make sure that the internal diagnostic socket pair fds do not conflict
 514                      with our choices */
 515                   diag_reserve_fd(fdi);
 516                   if (Dup2(wrpip[0], fdi) < 0) {
 517                      Error3("dup2(%d, %d): %s", wrpip[0], fdi, strerror(errno));
 518                      return -1;
 519                   }
 520                   Close(wrpip[0]);
 521                   /* applyopts_cloexec(fdi, *copts);*/  /* option is already consumed! */
 522                }
 523
 524                applyopts(sfd, fdi, copts, PH_LATE);
 525                applyopts(sfd, fdo, copts, PH_LATE);
 526                applyopts(sfd, fdi, copts, PH_LATE2);
 527                applyopts(sfd, fdo, copts, PH_LATE2);
 528
 529             } else {    /* socketpair */
 530                Close(sv[0]);
 531                if (rw != XIO_RDONLY && fdi != sv[1]) {
 532                   /* make sure that the internal diagnostic socket pair fds do not conflict
 533                      with our choices */
 534                   diag_reserve_fd(fdi);
 535                   if (Dup2(sv[1], fdi) < 0) {
 536                      Error3("dup2(%d, %d): %s", sv[1], fdi, strerror(errno));
 537                      return -1; }
 538                   /*0 Info2("dup2(%d, %d)", sv[1], fdi);*/
 539                }
 540                if (rw != XIO_WRONLY && fdo != sv[1]) {
 541                   /* make sure that the internal diagnostic socket pair fds do not conflict
 542                      with our choices */
 543                   diag_reserve_fd(fdo);
 544                   if (Dup2(sv[1], fdo) < 0) {
 545                      Error3("dup2(%d, %d): %s", sv[1], fdo, strerror(errno));
 546                      return -1; }
 547                   /*0 Info2("dup2(%d, %d)", sv[1], fdo);*/
 548                }
 549                if (fdi != sv[1] && fdo != sv[1]) {
 550                   applyopts_cloexec(sv[1], copts);
 551                   Close(sv[1]);
 552                }
 553
 554                applyopts(sfd, fdi, copts, PH_LATE);
 555                applyopts(sfd, fdi, copts, PH_LATE2);
 556             }
 557          if (withfork) {
 558             Info("notifying parent that child process is ready");
 559             Close(trigger[1]);  /* in child, notify parent that ready */
 560          }
 561       } /* withfork */
 562       else {
 563          applyopts(sfd, -1, copts, PH_LATE);
 564          applyopts(sfd, -1, copts, PH_LATE2);
 565       }
 566       _xioopen_setdelayeduser();
 567       if (withstderr) {
 568          *duptostderr = fdo;
 569       } else {
 570          *duptostderr = -1;
 571       }
 572
 573       *optsp = copts;
 574       return 0; /* indicate child process */
 575    }
 576
 577    /* for parent (this is our socat process) */
 578    Notice1("forked off child process "F_pid, pid);
 579    Close(trigger[1]);   /* in parent */
 580
 581 #if HAVE_PTY
 582    if (usepty) {
 583 #  if 0
 584       if (Close(ttyfd) < 0) {
 585          Info2("close(%d): %s", ttyfd, strerror(errno));
 586       }
 587 #  endif
 588    } else
 589 #endif /* HAVE_PTY */
 590    if (usepipes) {
 591       if (rw == XIO_RDONLY)  Close(rdpip[1]);
 592       if (rw == XIO_WRONLY)  Close(wrpip[0]);
 593    } else {
 594       Close(sv[1]);
 595    }
 596    sfd->para.exec.pid = pid;
 597
 598    if (applyopts_single(sfd, popts, PH_LATE) < 0)  return -1;
 599    applyopts(sfd, -1, popts, PH_LATE);
 600    applyopts(sfd, -1, popts, PH_LATE2);
 601    applyopts(sfd, -1, popts, PH_PASTEXEC);
 602    if ((numleft = leftopts(popts)) > 0) {
 603       showleft(popts);
 604       Error1("INTERNAL: %d option(s) remained unused", numleft);
 605       return STAT_NORETRY;
 606    }
 607
 608    {
 609       struct pollfd fds[1];
 610       fds[0].fd = trigger[0];
 611       fds[0].events = POLLIN|POLLHUP;
 612       Poll(fds, 1, -1);
 613       Info("child process notified parent that it is ready");
 614    }
 615
 616 #if HAVE_PTY
 617    applyopts(sfd, ptyfd, popts, PH_LATE);
 618 #endif /* HAVE_PTY */
 619    if (applyopts_single(sfd, popts, PH_LATE) < 0)
 620       return -1;
 621
 622    *optsp = popts;
 623    return pid;  /* indicate parent (main) process */
 624 }
 625 #endif /* WITH_EXEC || WITH_SYSTEM */
 626
 627
 628 int setopt_path(struct opt *opts, char **path) {
 629    if (retropt_string(opts, OPT_PATH, path) >= 0) {
 630       if (setenv("PATH", *path, 1) < 0) {
 631          Error1("setenv(\"PATH\", \"%s\", 1): insufficient space", *path);
 632          return -1;
 633       }
 634    }
 635    return 0;
 636 }