libiberty/pex-win32.c

   1 /* Utilities to execute a program in a subprocess (possibly linked by pipes
   2    with other subprocesses), and wait for it.  Generic Win32 specialization.
   3    Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006
   4    Free Software Foundation, Inc.
   5
   6 This file is part of the libiberty library.
   7 Libiberty is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU Library General Public
   9 License as published by the Free Software Foundation; either
  10 version 2 of the License, or (at your option) any later version.
  11
  12 Libiberty is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 Library General Public License for more details.
  16
  17 You should have received a copy of the GNU Library General Public
  18 License along with libiberty; see the file COPYING.LIB.  If not,
  19 write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 #include "pex-common.h"
  23
  24 #include <windows.h>
  25
  26 #ifdef HAVE_STDLIB_H
  27 #include <stdlib.h>
  28 #endif
  29 #ifdef HAVE_STRING_H
  30 #include <string.h>
  31 #endif
  32 #ifdef HAVE_UNISTD_H
  33 #include <unistd.h>
  34 #endif
  35 #ifdef HAVE_SYS_WAIT_H
  36 #include <sys/wait.h>
  37 #endif
  38
  39 #include <assert.h>
  40 #include <process.h>
  41 #include <io.h>
  42 #include <fcntl.h>
  43 #include <signal.h>
  44 #include <sys/stat.h>
  45 #include <errno.h>
  46 #include <ctype.h>
  47
  48 /* mingw32 headers may not define the following.  */
  49
  50 #ifndef _P_WAIT
  51 #  define _P_WAIT       0
  52 #  define _P_NOWAIT     1
  53 #  define _P_OVERLAY    2
  54 #  define _P_NOWAITO    3
  55 #  define _P_DETACH     4
  56
  57 #  define WAIT_CHILD            0
  58 #  define WAIT_GRANDCHILD       1
  59 #endif
  60
  61 #define MINGW_NAME "Minimalist GNU for Windows"
  62 #define MINGW_NAME_LEN (sizeof(MINGW_NAME) - 1)
  63
  64 extern char *stpcpy (char *dst, const char *src);
  65
  66 /* Ensure that the executable pathname uses Win32 backslashes. This
  67    is not necessary on NT, but on W9x, forward slashes causes
  68    failure of spawn* and exec* functions (and probably any function
  69    that calls CreateProcess) *iff* the executable pathname (argv[0])
  70    is a quoted string.  And quoting is necessary in case a pathname
  71    contains embedded white space.  You can't win.  */
  72 static void
  73 backslashify (char *s)
  74 {
  75   while ((s = strchr (s, '/')) != NULL)
  76     *s = '\\';
  77   return;
  78 }
  79
  80 static int pex_win32_open_read (struct pex_obj *, const char *, int);
  81 static int pex_win32_open_write (struct pex_obj *, const char *, int);
  82 static long pex_win32_exec_child (struct pex_obj *, int, const char *,
  83                                   char * const *, char * const *,
  84                                   int, int, int, int,
  85                                   const char **, int *);
  86 static int pex_win32_close (struct pex_obj *, int);
  87 static int pex_win32_wait (struct pex_obj *, long, int *,
  88                            struct pex_time *, int, const char **, int *);
  89 static int pex_win32_pipe (struct pex_obj *, int *, int);
  90 static FILE *pex_win32_fdopenr (struct pex_obj *, int, int);
  91 static FILE *pex_win32_fdopenw (struct pex_obj *, int, int);
  92
  93 /* The list of functions we pass to the common routines.  */
  94
  95 const struct pex_funcs funcs =
  96 {
  97   pex_win32_open_read,
  98   pex_win32_open_write,
  99   pex_win32_exec_child,
 100   pex_win32_close,
 101   pex_win32_wait,
 102   pex_win32_pipe,
 103   pex_win32_fdopenr,
 104   pex_win32_fdopenw,
 105   NULL /* cleanup */
 106 };
 107
 108 /* Return a newly initialized pex_obj structure.  */
 109
 110 struct pex_obj *
 111 pex_init (int flags, const char *pname, const char *tempbase)
 112 {
 113   return pex_init_common (flags, pname, tempbase, &funcs);
 114 }
 115
 116 /* Open a file for reading.  */
 117
 118 static int
 119 pex_win32_open_read (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name,
 120                      int binary)
 121 {
 122   return _open (name, _O_RDONLY | (binary ? _O_BINARY : _O_TEXT));
 123 }
 124
 125 /* Open a file for writing.  */
 126
 127 static int
 128 pex_win32_open_write (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name,
 129                       int binary)
 130 {
 131   /* Note that we can't use O_EXCL here because gcc may have already
 132      created the temporary file via make_temp_file.  */
 133   return _open (name,
 134                 (_O_WRONLY | _O_CREAT | _O_TRUNC
 135                  | (binary ? _O_BINARY : _O_TEXT)),
 136                 _S_IREAD | _S_IWRITE);
 137 }
 138
 139 /* Close a file.  */
 140
 141 static int
 142 pex_win32_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd)
 143 {
 144   return _close (fd);
 145 }
 146
 147 #ifdef USE_MINGW_MSYS
 148 static const char *mingw_keys[] = {"SOFTWARE", "Microsoft", "Windows", "CurrentVersion", "Uninstall", NULL};
 149
 150 /* Tack the executable on the end of a (possibly slash terminated) buffer
 151    and convert everything to \. */
 152 static const char *
 153 tack_on_executable (char *buf, const char *executable)
 154 {
 155   char *p = strchr (buf, '\0');
 156   if (p > buf && (p[-1] == '\\' || p[-1] == '/'))
 157     p[-1] = '\0';
 158   backslashify (strcat (buf, executable));
 159   return buf;
 160 }
 161
 162 /* Walk down a registry hierarchy until the end.  Return the key. */
 163 static HKEY
 164 openkey (HKEY hStart, const char *keys[])
 165 {
 166   HKEY hKey, hTmp;
 167   for (hKey = hStart; *keys; keys++)
 168     {
 169       LONG res;
 170       hTmp = hKey;
 171       res = RegOpenKey (hTmp, *keys, &hKey);
 172
 173       if (hTmp != HKEY_LOCAL_MACHINE)
 174         RegCloseKey (hTmp);
 175
 176       if (res != ERROR_SUCCESS)
 177         return NULL;
 178     }
 179   return hKey;
 180 }
 181
 182 /* Return the "mingw root" as derived from the mingw uninstall information. */
 183 static const char *
 184 mingw_rootify (const char *executable)
 185 {
 186   HKEY hKey, hTmp;
 187   DWORD maxlen;
 188   char *namebuf, *foundbuf;
 189   DWORD i;
 190   LONG res;
 191
 192   /* Open the uninstall "directory". */
 193   hKey = openkey (HKEY_LOCAL_MACHINE, mingw_keys);
 194
 195   /* Not found. */
 196   if (!hKey)
 197     return executable;
 198
 199   /* Need to enumerate all of the keys here looking for one the most recent
 200      one for MinGW. */
 201   if (RegQueryInfoKey (hKey, NULL, NULL, NULL, NULL, &maxlen, NULL, NULL,
 202                        NULL, NULL, NULL, NULL) != ERROR_SUCCESS)
 203     {
 204       RegCloseKey (hKey);
 205       return executable;
 206     }
 207   namebuf = XNEWVEC (char, ++maxlen);
 208   foundbuf = XNEWVEC (char, maxlen);
 209   foundbuf[0] = '\0';
 210   if (!namebuf || !foundbuf)
 211     {
 212       RegCloseKey (hKey);
 213       if (namebuf)
 214         free (namebuf);
 215       if (foundbuf)
 216         free (foundbuf);
 217       return executable;
 218     }
 219
 220   /* Look through all of the keys for one that begins with Minimal GNU...
 221      Try to get the latest version by doing a string compare although that
 222      string never really works with version number sorting. */
 223   for (i = 0; RegEnumKey (hKey, i, namebuf, maxlen) == ERROR_SUCCESS; i++)
 224     {
 225       int match = strcasecmp (namebuf, MINGW_NAME);
 226       if (match < 0)
 227         continue;
 228       if (match > 0 && strncasecmp (namebuf, MINGW_NAME, MINGW_NAME_LEN) > 0)
 229         continue;
 230       if (strcasecmp (namebuf, foundbuf) > 0)
 231         strcpy (foundbuf, namebuf);
 232     }
 233   free (namebuf);
 234
 235   /* If foundbuf is empty, we didn't find anything.  Punt. */
 236   if (!foundbuf[0])
 237     {
 238       free (foundbuf);
 239       RegCloseKey (hKey);
 240       return executable;
 241     }
 242
 243   /* Open the key that we wanted */
 244   res = RegOpenKey (hKey, foundbuf, &hTmp);
 245   RegCloseKey (hKey);
 246   free (foundbuf);
 247
 248   /* Don't know why this would fail, but you gotta check */
 249   if (res != ERROR_SUCCESS)
 250     return executable;
 251
 252   maxlen = 0;
 253   /* Get the length of the value pointed to by InstallLocation */
 254   if (RegQueryValueEx (hTmp, "InstallLocation", 0, NULL, NULL,
 255                        &maxlen) != ERROR_SUCCESS || maxlen == 0)
 256     {
 257       RegCloseKey (hTmp);
 258       return executable;
 259     }
 260
 261   /* Allocate space for the install location */
 262   foundbuf = XNEWVEC (char, maxlen + strlen (executable));
 263   if (!foundbuf)
 264     {
 265       free (foundbuf);
 266       RegCloseKey (hTmp);
 267     }
 268
 269   /* Read the install location into the buffer */
 270   res = RegQueryValueEx (hTmp, "InstallLocation", 0, NULL, (LPBYTE) foundbuf,
 271                          &maxlen);
 272   RegCloseKey (hTmp);
 273   if (res != ERROR_SUCCESS)
 274     {
 275       free (foundbuf);
 276       return executable;
 277     }
 278
 279   /* Concatenate the install location and the executable, turn all slashes
 280      to backslashes, and return that. */
 281   return tack_on_executable (foundbuf, executable);
 282 }
 283
 284 /* Read the install location of msys from it's installation file and
 285    rootify the executable based on that. */
 286 static const char *
 287 msys_rootify (const char *executable)
 288 {
 289   size_t bufsize = 64;
 290   size_t execlen = strlen (executable) + 1;
 291   char *buf;
 292   DWORD res = 0;
 293   for (;;)
 294     {
 295       buf = XNEWVEC (char, bufsize + execlen);
 296       if (!buf)
 297         break;
 298       res = GetPrivateProfileString ("InstallSettings", "InstallPath", NULL,
 299                                      buf, bufsize, "msys.ini");
 300       if (!res)
 301         break;
 302       if (strlen (buf) < bufsize)
 303         break;
 304       res = 0;
 305       free (buf);
 306       bufsize *= 2;
 307       if (bufsize > 65536)
 308         {
 309           buf = NULL;
 310           break;
 311         }
 312     }
 313
 314   if (res)
 315     return tack_on_executable (buf, executable);
 316
 317   /* failed */
 318   if (buf)
 319     free (buf);
 320   return executable;
 321 }
 322 #endif
 323
 324 /* Return a Windows command-line from ARGV.  It is the caller's
 325    responsibility to free the string returned.  */
 326
 327 static char *
 328 argv_to_cmdline (char *const *argv)
 329 {
 330   char *cmdline;
 331   char *p;
 332   size_t cmdline_len;
 333   int i, j, k;
 334
 335   cmdline_len = 0;
 336   for (i = 0; argv[i]; i++)
 337     {
 338       /* We quote every last argument.  This simplifies the problem;
 339          we need only escape embedded double-quotes and immediately
 340          preceeding backslash characters.  A sequence of backslach characters
 341          that is not follwed by a double quote character will not be
 342          escaped.  */
 343       for (j = 0; argv[i][j]; j++)
 344         {
 345           if (argv[i][j] == '"')
 346             {
 347               /* Escape preceeding backslashes.  */
 348               for (k = j - 1; k >= 0 && argv[i][k] == '\\'; k--)
 349                 cmdline_len++;
 350               /* Escape the qote character.  */
 351               cmdline_len++;
 352             }
 353         }
 354       /* Trailing backslashes also need to be escaped because they will be
 355          followed by the terminating quote.  */
 356       for (k = j - 1; k >= 0 && argv[i][k] == '\\'; k--)
 357         cmdline_len++;
 358       cmdline_len += j;
 359       cmdline_len += 3;  /* for leading and trailing quotes and space */
 360     }
 361   cmdline = XNEWVEC (char, cmdline_len);
 362   p = cmdline;
 363   for (i = 0; argv[i]; i++)
 364     {
 365       *p++ = '"';
 366       for (j = 0; argv[i][j]; j++)
 367         {
 368           if (argv[i][j] == '"')
 369             {
 370               for (k = j - 1; k >= 0 && argv[i][k] == '\\'; k--)
 371                 *p++ = '\\';
 372               *p++ = '\\';
 373             }
 374           *p++ = argv[i][j];
 375         }
 376       for (k = j - 1; k >= 0 && argv[i][k] == '\\'; k--)
 377         *p++ = '\\';
 378       *p++ = '"';
 379       *p++ = ' ';
 380     }
 381   p[-1] = '\0';
 382   return cmdline;
 383 }
 384
 385 /* We'll try the passed filename with all the known standard
 386    extensions, and then without extension.  We try no extension
 387    last so that we don't try to run some random extension-less
 388    file that might be hanging around.  We try both extension
 389    and no extension so that we don't need any fancy logic
 390    to determine if a file has extension.  */
 391 static const char *const
 392 std_suffixes[] = {
 393   ".com",
 394   ".exe",
 395   ".bat",
 396   ".cmd",
 397   "",
 398   0
 399 };
 400
 401 /* Returns the full path to PROGRAM.  If SEARCH is true, look for
 402    PROGRAM in each directory in PATH.  */
 403
 404 static char *
 405 find_executable (const char *program, BOOL search)
 406 {
 407   char *full_executable;
 408   char *e;
 409   size_t fe_len;
 410   const char *path = 0;
 411   const char *const *ext;
 412   const char *p, *q;
 413   size_t proglen = strlen (program);
 414   int has_slash = (strchr (program, '/') || strchr (program, '\\'));
 415   HANDLE h;
 416
 417   if (has_slash)
 418     search = FALSE;
 419
 420   if (search)
 421     path = getenv ("PATH");
 422   if (!path)
 423     path = "";
 424
 425   fe_len = 0;
 426   for (p = path; *p; p = q)
 427     {
 428       q = p;
 429       while (*q != ';' && *q != '\0')
 430         q++;
 431       if ((size_t)(q - p) > fe_len)
 432         fe_len = q - p;
 433       if (*q == ';')
 434         q++;
 435     }
 436   fe_len = fe_len + 1 + proglen + 5 /* space for extension */;
 437   full_executable = XNEWVEC (char, fe_len);
 438
 439   p = path;
 440   do
 441     {
 442       q = p;
 443       while (*q != ';' && *q != '\0')
 444         q++;
 445
 446       e = full_executable;
 447       memcpy (e, p, q - p);
 448       e += (q - p);
 449       if (q - p)
 450         *e++ = '\\';
 451       strcpy (e, program);
 452
 453       if (*q == ';')
 454         q++;
 455
 456       for (e = full_executable; *e; e++)
 457         if (*e == '/')
 458           *e = '\\';
 459
 460       /* At this point, e points to the terminating NUL character for
 461          full_executable.  */
 462       for (ext = std_suffixes; *ext; ext++)
 463         {
 464           /* Remove any current extension.  */
 465           *e = '\0';
 466           /* Add the new one.  */
 467           strcat (full_executable, *ext);
 468
 469           /* Attempt to open this file.  */
 470           h = CreateFile (full_executable, GENERIC_READ,
 471                           FILE_SHARE_READ | FILE_SHARE_WRITE,
 472                           0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
 473           if (h != INVALID_HANDLE_VALUE)
 474             goto found;
 475         }
 476       p = q;
 477     }
 478   while (*p);
 479   free (full_executable);
 480   return 0;
 481
 482  found:
 483   CloseHandle (h);
 484   return full_executable;
 485 }
 486
 487 /* Low-level process creation function and helper.  */
 488
 489 static int
 490 env_compare (const void *a_ptr, const void *b_ptr)
 491 {
 492   const char *a;
 493   const char *b;
 494   unsigned char c1;
 495   unsigned char c2;
 496
 497   a = *(const char **) a_ptr;
 498   b = *(const char **) b_ptr;
 499
 500   /* a and b will be of the form: VAR=VALUE
 501      We compare only the variable name part here using a case-insensitive
 502      comparison algorithm.  It might appear that in fact strcasecmp () can
 503      take the place of this whole function, and indeed it could, save for
 504      the fact that it would fail in cases such as comparing A1=foo and
 505      A=bar (because 1 is less than = in the ASCII character set).
 506      (Environment variables containing no numbers would work in such a
 507      scenario.)  */
 508
 509   do
 510     {
 511       c1 = (unsigned char) tolower (*a++);
 512       c2 = (unsigned char) tolower (*b++);
 513
 514       if (c1 == '=')
 515         c1 = '\0';
 516
 517       if (c2 == '=')
 518         c2 = '\0';
 519     }
 520   while (c1 == c2 && c1 != '\0');
 521
 522   return c1 - c2;
 523 }
 524
 525 static long
 526 win32_spawn (const char *executable,
 527              BOOL search,
 528              char *const *argv,
 529              char *const *env, /* array of strings of the form: VAR=VALUE */
 530              DWORD dwCreationFlags,
 531              LPSTARTUPINFO si,
 532              LPPROCESS_INFORMATION pi)
 533 {
 534   char *full_executable;
 535   char *cmdline;
 536   char **env_copy;
 537   char *env_block = NULL;
 538
 539   full_executable = NULL;
 540   cmdline = NULL;
 541
 542   if (env)
 543     {
 544       int env_size;
 545
 546       /* Count the number of environment bindings supplied.  */
 547       for (env_size = 0; env[env_size]; env_size++)
 548         continue;
 549
 550       /* Assemble an environment block, if required.  This consists of
 551          VAR=VALUE strings juxtaposed (with one null character between each
 552          pair) and an additional null at the end.  */
 553       if (env_size > 0)
 554         {
 555           int var;
 556           int total_size = 1; /* 1 is for the final null.  */
 557           char *bufptr;
 558
 559           /* Windows needs the members of the block to be sorted by variable
 560              name.  */
 561           env_copy = (char **) alloca (sizeof (char *) * env_size);
 562           memcpy (env_copy, env, sizeof (char *) * env_size);
 563           qsort (env_copy, env_size, sizeof (char *), env_compare);
 564
 565           for (var = 0; var < env_size; var++)
 566             total_size += strlen (env[var]) + 1;
 567
 568           env_block = XNEWVEC (char, total_size);
 569           bufptr = env_block;
 570           for (var = 0; var < env_size; var++)
 571             bufptr = stpcpy (bufptr, env_copy[var]) + 1;
 572
 573           *bufptr = '\0';
 574         }
 575     }
 576
 577   full_executable = find_executable (executable, search);
 578   if (!full_executable)
 579     goto error;
 580   cmdline = argv_to_cmdline (argv);
 581   if (!cmdline)
 582     goto error;
 583
 584   /* Create the child process.  */
 585   if (!CreateProcess (full_executable, cmdline,
 586                       /*lpProcessAttributes=*/NULL,
 587                       /*lpThreadAttributes=*/NULL,
 588                       /*bInheritHandles=*/TRUE,
 589                       dwCreationFlags,
 590                       (LPVOID) env_block,
 591                       /*lpCurrentDirectory=*/NULL,
 592                       si,
 593                       pi))
 594     {
 595       if (env_block)
 596         free (env_block);
 597
 598       free (full_executable);
 599
 600       return -1;
 601     }
 602
 603   /* Clean up.  */
 604   CloseHandle (pi->hThread);
 605   free (full_executable);
 606   if (env_block)
 607     free (env_block);
 608
 609   return (long) pi->hProcess;
 610
 611  error:
 612   if (env_block)
 613     free (env_block);
 614   if (cmdline)
 615     free (cmdline);
 616   if (full_executable)
 617     free (full_executable);
 618
 619   return -1;
 620 }
 621
 622 static long
 623 spawn_script (const char *executable, char *const *argv,
 624               char* const *env,
 625               DWORD dwCreationFlags,
 626               LPSTARTUPINFO si,
 627               LPPROCESS_INFORMATION pi)
 628 {
 629   int pid = -1;
 630   int save_errno = errno;
 631   int fd = _open (executable, _O_RDONLY);
 632
 633   if (fd >= 0)
 634     {
 635       char buf[MAX_PATH + 5];
 636       int len = _read (fd, buf, sizeof (buf) - 1);
 637       _close (fd);
 638       if (len > 3)
 639         {
 640           char *eol;
 641           buf[len] = '\0';
 642           eol = strchr (buf, '\n');
 643           if (eol && strncmp (buf, "#!", 2) == 0)
 644             {
 645               char *executable1;
 646               const char ** avhere = (const char **) --argv;
 647               do
 648                 *eol = '\0';
 649               while (*--eol == '\r' || *eol == ' ' || *eol == '\t');
 650               for (executable1 = buf + 2; *executable1 == ' ' || *executable1 == '\t'; executable1++)
 651                 continue;
 652
 653               backslashify (executable1);
 654               *avhere = executable1;
 655 #ifndef USE_MINGW_MSYS
 656               executable = strrchr (executable1, '\\') + 1;
 657               if (!executable)
 658                 executable = executable1;
 659               pid = win32_spawn (executable, TRUE, argv, env,
 660                                  dwCreationFlags, si, pi);
 661 #else
 662               if (strchr (executable1, '\\') == NULL)
 663                 pid = win32_spawn (executable1, TRUE, argv, env,
 664                                    dwCreationFlags, si, pi);
 665               else if (executable1[0] != '\\')
 666                 pid = win32_spawn (executable1, FALSE, argv, env,
 667                                    dwCreationFlags, si, pi);
 668               else
 669                 {
 670                   const char *newex = mingw_rootify (executable1);
 671                   *avhere = newex;
 672                   pid = win32_spawn (newex, FALSE, argv, env,
 673                                      dwCreationFlags, si, pi);
 674                   if (executable1 != newex)
 675                     free ((char *) newex);
 676                   if (pid < 0)
 677                     {
 678                       newex = msys_rootify (executable1);
 679                       if (newex != executable1)
 680                         {
 681                           *avhere = newex;
 682                           pid = win32_spawn (newex, FALSE, argv, env,
 683                                              dwCreationFlags, si, pi);
 684                           free ((char *) newex);
 685                         }
 686                     }
 687                 }
 688 #endif
 689             }
 690         }
 691     }
 692   if (pid < 0)
 693     errno = save_errno;
 694   return pid;
 695 }
 696
 697 /* Execute a child.  */
 698
 699 static long
 700 pex_win32_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED, int flags,
 701                       const char *executable, char * const * argv,
 702                       char* const* env,
 703                       int in, int out, int errdes,
 704                       int toclose ATTRIBUTE_UNUSED,
 705                       const char **errmsg,
 706                       int *err)
 707 {
 708   long pid;
 709   HANDLE stdin_handle;
 710   HANDLE stdout_handle;
 711   HANDLE stderr_handle;
 712   DWORD dwCreationFlags;
 713   OSVERSIONINFO version_info;
 714   STARTUPINFO si;
 715   PROCESS_INFORMATION pi;
 716
 717   stdin_handle = INVALID_HANDLE_VALUE;
 718   stdout_handle = INVALID_HANDLE_VALUE;
 719   stderr_handle = INVALID_HANDLE_VALUE;
 720
 721   stdin_handle = (HANDLE) _get_osfhandle (in);
 722   stdout_handle = (HANDLE) _get_osfhandle (out);
 723   if (!(flags & PEX_STDERR_TO_STDOUT))
 724     stderr_handle = (HANDLE) _get_osfhandle (errdes);
 725   else
 726     stderr_handle = stdout_handle;
 727
 728   /* Determine the version of Windows we are running on.  */
 729   version_info.dwOSVersionInfoSize = sizeof (version_info);
 730   GetVersionEx (&version_info);
 731   if (version_info.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS)
 732     /* On Windows 95/98/ME the CREATE_NO_WINDOW flag is not
 733        supported, so we cannot avoid creating a console window.  */
 734     dwCreationFlags = 0;
 735   else
 736     {
 737       HANDLE conout_handle;
 738
 739       /* Determine whether or not we have an associated console.  */
 740       conout_handle = CreateFile("CONOUT$",
 741                                  GENERIC_WRITE,
 742                                  FILE_SHARE_WRITE,
 743                                  /*lpSecurityAttributes=*/NULL,
 744                                  OPEN_EXISTING,
 745                                  FILE_ATTRIBUTE_NORMAL,
 746                                  /*hTemplateFile=*/NULL);
 747       if (conout_handle == INVALID_HANDLE_VALUE)
 748         /* There is no console associated with this process.  Since
 749            the child is a console process, the OS would normally
 750            create a new console Window for the child.  Since we'll be
 751            redirecting the child's standard streams, we do not need
 752            the console window.  */
 753         dwCreationFlags = CREATE_NO_WINDOW;
 754       else
 755         {
 756           /* There is a console associated with the process, so the OS
 757              will not create a new console.  And, if we use
 758              CREATE_NO_WINDOW in this situation, the child will have
 759              no associated console.  Therefore, if the child's
 760              standard streams are connected to the console, the output
 761              will be discarded.  */
 762           CloseHandle(conout_handle);
 763           dwCreationFlags = 0;
 764         }
 765     }
 766
 767   /* Since the child will be a console process, it will, by default,
 768      connect standard input/output to its console.  However, we want
 769      the child to use the handles specifically designated above.  In
 770      addition, if there is no console (such as when we are running in
 771      a Cygwin X window), then we must redirect the child's
 772      input/output, as there is no console for the child to use.  */
 773   memset (&si, 0, sizeof (si));
 774   si.cb = sizeof (si);
 775   si.dwFlags = STARTF_USESTDHANDLES;
 776   si.hStdInput = stdin_handle;
 777   si.hStdOutput = stdout_handle;
 778   si.hStdError = stderr_handle;
 779
 780   /* Create the child process.  */
 781   pid = win32_spawn (executable, (flags & PEX_SEARCH) != 0,
 782                      argv, env, dwCreationFlags, &si, &pi);
 783   if (pid == -1)
 784     pid = spawn_script (executable, argv, env, dwCreationFlags,
 785                         &si, &pi);
 786   if (pid == -1)
 787     {
 788       *err = ENOENT;
 789       *errmsg = "CreateProcess";
 790     }
 791
 792   /* Close the standard output and standard error handles in the
 793      parent.  */
 794   if (out != STDOUT_FILENO)
 795     obj->funcs->close (obj, out);
 796   if (errdes != STDERR_FILENO)
 797     obj->funcs->close (obj, errdes);
 798
 799   return pid;
 800 }
 801
 802 /* Wait for a child process to complete.  MS CRTDLL doesn't return
 803    enough information in status to decide if the child exited due to a
 804    signal or not, rather it simply returns an integer with the exit
 805    code of the child; eg., if the child exited with an abort() call
 806    and didn't have a handler for SIGABRT, it simply returns with
 807    status == 3.  We fix the status code to conform to the usual WIF*
 808    macros.  Note that WIFSIGNALED will never be true under CRTDLL. */
 809
 810 static int
 811 pex_win32_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, long pid,
 812                 int *status, struct pex_time *time, int done ATTRIBUTE_UNUSED,
 813                 const char **errmsg, int *err)
 814 {
 815   DWORD termstat;
 816   HANDLE h;
 817
 818   if (time != NULL)
 819     memset (time, 0, sizeof *time);
 820
 821   h = (HANDLE) pid;
 822
 823   /* FIXME: If done is non-zero, we should probably try to kill the
 824      process.  */
 825   if (WaitForSingleObject (h, INFINITE) != WAIT_OBJECT_0)
 826     {
 827       CloseHandle (h);
 828       *err = ECHILD;
 829       *errmsg = "WaitForSingleObject";
 830       return -1;
 831     }
 832
 833   GetExitCodeProcess (h, &termstat);
 834   CloseHandle (h);
 835
 836   /* A value of 3 indicates that the child caught a signal, but not
 837      which one.  Since only SIGABRT, SIGFPE and SIGINT do anything, we
 838      report SIGABRT.  */
 839   if (termstat == 3)
 840     *status = SIGABRT;
 841   else
 842     *status = (termstat & 0xff) << 8;
 843
 844   return 0;
 845 }
 846
 847 /* Create a pipe.  */
 848
 849 static int
 850 pex_win32_pipe (struct pex_obj *obj ATTRIBUTE_UNUSED, int *p,
 851                 int binary)
 852 {
 853   return _pipe (p, 256, binary ? _O_BINARY : _O_TEXT);
 854 }
 855
 856 /* Get a FILE pointer to read from a file descriptor.  */
 857
 858 static FILE *
 859 pex_win32_fdopenr (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd,
 860                    int binary)
 861 {
 862   return fdopen (fd, binary ? "rb" : "r");
 863 }
 864
 865 static FILE *
 866 pex_win32_fdopenw (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd,
 867                    int binary)
 868 {
 869   HANDLE h = (HANDLE) _get_osfhandle (fd);
 870   if (h == INVALID_HANDLE_VALUE)
 871     return NULL;
 872   if (! SetHandleInformation (h, HANDLE_FLAG_INHERIT, 0))
 873     return NULL;
 874   return fdopen (fd, binary ? "wb" : "w");
 875 }
 876
 877 #ifdef MAIN
 878 #include <stdio.h>
 879
 880 int
 881 main (int argc ATTRIBUTE_UNUSED, char **argv)
 882 {
 883   char const *errmsg;
 884   int err;
 885   argv++;
 886   printf ("%ld\n", pex_win32_exec_child (NULL, PEX_SEARCH, argv[0], argv, NULL, 0, 0, 1, 2, &errmsg, &err));
 887   exit (0);
 888 }
 889 #endif