xemacs-beta / src / callproc.c

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
/* Synchronous subprocess invocation for XEmacs.
   Copyright (C) 1985, 86, 87, 88, 93, 94, 95 Free Software Foundation, Inc.

This file is part of XEmacs.

XEmacs is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

XEmacs is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with XEmacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* Synched up with: Mule 2.0, FSF 19.30. */

#include <config.h>
#include "lisp.h"

#include "buffer.h"
#include "commands.h"
#include "insdel.h"
#include "lstream.h"
#include "paths.h"
#include "process.h"
#include "sysdep.h"
#include "window.h"

#include "sysfile.h"
#include "systime.h"
#include "sysproc.h"
#include "syssignal.h" /* Always include before systty.h */
#include "systty.h"


#ifdef DOS_NT
/* When we are starting external processes we need to know whether they
   take binary input (no conversion) or text input (\n is converted to
   \r\n).  Similar for output: if newlines are written as \r\n then it's
   text process output, otherwise it's binary.  */
Lisp_Object Vbinary_process_input;
Lisp_Object Vbinary_process_output;
#endif /* DOS_NT */

Lisp_Object Vexec_path, Vexec_directory, Vdata_directory, Vdoc_directory;
Lisp_Object Vconfigure_info_directory, Vsite_directory;

/* The default base directory XEmacs is installed under. */
Lisp_Object Vprefix_directory;

Lisp_Object Vshell_file_name;

/* The environment to pass to all subprocesses when they are started.
   This is in the semi-bogus format of ("VAR=VAL" "VAR2=VAL2" ... )
 */
Lisp_Object Vprocess_environment;

/* True iff we are about to fork off a synchronous process or if we
   are waiting for it.  */
volatile int synch_process_alive;

/* Nonzero => this is a string explaining death of synchronous subprocess.  */
CONST char *synch_process_death;

/* If synch_process_death is zero,
   this is exit code of synchronous subprocess.  */
int synch_process_retcode;

/* Clean up when exiting Fcall_process_internal.
   On MSDOS, delete the temporary file on any kind of termination.
   On Unix, kill the process and any children on termination by signal.  */

/* Nonzero if this is termination due to exit.  */
static int call_process_exited;

#ifndef VMS  /* VMS version is in vmsproc.c.  */

static Lisp_Object
call_process_kill (Lisp_Object fdpid)
{
  Lisp_Object fd = Fcar (fdpid);
  Lisp_Object pid = Fcdr (fdpid);

  if (!NILP (fd))
    close (XINT (fd));

  if (!NILP (pid))
    EMACS_KILLPG (XINT (pid), SIGKILL);
  
  synch_process_alive = 0;
  return Qnil;
}

static Lisp_Object
call_process_cleanup (Lisp_Object fdpid)
{
#ifdef MSDOS
  /* for MSDOS fdpid is really (fd . tempfile)  */
  Lisp_Object file = Fcdr (fdpid);
  close (XINT (Fcar (fdpid)));
  if (strcmp (XSTRING_DATA (file), NULL_DEVICE) != 0)
    unlink (XSTRING_DATA (file));
#else /* not MSDOS */
  int fd = XINT (Fcar (fdpid));
  int pid = XINT (Fcdr (fdpid));

  if (!call_process_exited &&
      EMACS_KILLPG (pid, SIGINT) == 0)
  {
    int speccount = specpdl_depth ();

    record_unwind_protect (call_process_kill, fdpid);
    /* #### "c-G" -- need non-consing Single-key-description */
    message ("Waiting for process to die...(type C-g again to kill it instantly)");

    /* "Discard" the unwind protect.  */
    XCAR (fdpid) = Qnil;
    XCDR (fdpid) = Qnil;
    unbind_to (speccount, Qnil);

    message ("Waiting for process to die... done");
  }
  synch_process_alive = 0;
  close (fd);
#endif /* not MSDOS */
  return Qnil;
}

static Lisp_Object fork_error;
#if 0 /* UNUSED */
static void
report_fork_error (char *string, Lisp_Object data)
{
  Lisp_Object errstring = build_string (strerror (errno));

  /* System error messages are capitalized.  Downcase the initial. */
  set_string_char (XSTRING (errstring), 0,
		   DOWNCASE (current_buffer,
			     string_char (XSTRING (errstring), 0)));

  fork_error = Fcons (build_string (string), Fcons (errstring, data));

  /* terminate this branch of the fork, without closing stdin/out/etc. */
  _exit (1);
}
#endif /* unused */

DEFUN ("call-process-internal", Fcall_process_internal, 1, MANY, 0, /*
Call PROGRAM synchronously in separate process, with coding-system specified.
Arguments are
 (PROGRAM &optional INFILE BUFFER DISPLAY &rest ARGS).
The program's input comes from file INFILE (nil means `/dev/null').
Insert output in BUFFER before point; t means current buffer;
 nil for BUFFER means discard it; 0 means discard and don't wait.
BUFFER can also have the form (REAL-BUFFER STDERR-FILE); in that case,
REAL-BUFFER says what to do with standard output, as above,
while STDERR-FILE says what to do with standard error in the child.
STDERR-FILE may be nil (discard standard error output),
t (mix it with ordinary output), or a file name string.

Fourth arg DISPLAY non-nil means redisplay buffer as output is inserted.
Remaining arguments are strings passed as command arguments to PROGRAM.

If BUFFER is 0, `call-process' returns immediately with value nil.
Otherwise it waits for PROGRAM to terminate and returns a numeric exit status
 or a signal description string.
If you quit, the process is killed with SIGINT, or SIGKILL if you
 quit again.
*/
       (int nargs, Lisp_Object *args))
{
  /* This function can GC */
  Lisp_Object infile, buffer, current_dir, display, path;
  int fd[2];
  int filefd;
  int pid;
  char buf[16384];
  char *bufptr = buf;
  int bufsize = 16384;
  int speccount = specpdl_depth ();
  struct gcpro gcpro1;
  char **new_argv
    = (char **) alloca ((max (2, nargs - 2)) * sizeof (char *));
  
  /* File to use for stderr in the child.
     t means use same as standard output.  */
  Lisp_Object error_file;
#ifdef MSDOS
  char *outf, *tempfile;
  int outfilefd;
#endif /* MSDOS */
  
  CHECK_STRING (args[0]);

  error_file = Qt;

#if defined (NO_SUBPROCESSES)
  /* Without asynchronous processes we cannot have BUFFER == 0.  */
  if (nargs >= 3 && !INTP (args[2]))
    error ("Operating system cannot handle asynchronous subprocesses");
#endif /* NO_SUBPROCESSES */

  /* Do this before building new_argv because GC in Lisp code
   *  called by various filename-hacking routines might relocate strings */
  locate_file (Vexec_path, args[0], EXEC_SUFFIXES, &path, X_OK);

  /* Make sure that the child will be able to chdir to the current
     buffer's current directory, or its unhandled equivalent.  We
     can't just have the child check for an error when it does the
     chdir, since it's in a vfork. */
  {
    struct gcpro gcpro1, gcpro2;
    /* Do this test before building new_argv because GC in Lisp code 
     *  called by various filename-hacking routines might relocate strings */
    /* Make sure that the child will be able to chdir to the current
       buffer's current directory.  We can't just have the child check
       for an error when it does the chdir, since it's in a vfork.  */

    GCPRO2 (current_dir, path);   /* Caller gcprotects args[] */
    current_dir = current_buffer->directory;
    current_dir = Funhandled_file_name_directory (current_dir);
    current_dir = expand_and_dir_to_file (current_dir, Qnil);
#if 0
  /* I don't know how RMS intends this crock of shit to work, but it
     breaks everything in the presence of ange-ftp-visited files, so
     fuck it. */
    if (NILP (Ffile_accessible_directory_p (current_dir)))
      report_file_error ("Setting current directory",
                         Fcons (current_buffer->directory, Qnil));
#endif /* 0 */
    UNGCPRO;
  }

  if (nargs >= 2 && ! NILP (args[1]))
    {
      struct gcpro gcpro1;
      GCPRO1 (current_buffer->directory);
      infile = Fexpand_file_name (args[1], current_buffer->directory);
      UNGCPRO;
      CHECK_STRING (infile);
    }
  else
    infile = build_string (NULL_DEVICE);

  GCPRO1 (infile);		/* Fexpand_file_name might trash it */

  if (nargs >= 3)
    {
      buffer = args[2];

      /* If BUFFER is a list, its meaning is
	 (BUFFER-FOR-STDOUT FILE-FOR-STDERR).  */
      if (CONSP (buffer))
	{
	  if (CONSP (XCDR (buffer)))
	    {
	      Lisp_Object file_for_stderr = XCAR (XCDR (buffer));

	      if (NILP (file_for_stderr) || EQ (Qt, file_for_stderr))
		error_file = file_for_stderr;
	      else
		error_file = Fexpand_file_name (file_for_stderr, Qnil);
	    }

	  buffer = XCAR (buffer);
	}

      if (!(EQ (buffer, Qnil)
	    || EQ (buffer, Qt)
	    || ZEROP (buffer)))
	{
	  Lisp_Object spec_buffer;
	  spec_buffer = buffer;
	  buffer = Fget_buffer (buffer);
	  /* Mention the buffer name for a better error message.  */
	  if (NILP (buffer))
	    CHECK_BUFFER (spec_buffer);
	  CHECK_BUFFER (buffer);
	}
    }
  else 
    buffer = Qnil;

  UNGCPRO;

  display = ((nargs >= 4) ? args[3] : Qnil);

  /* From here we assume we won't GC (unless an error is signaled). */
  {
    REGISTER int i;
    for (i = 4; i < nargs; i++)
      {
	CHECK_STRING (args[i]);
	new_argv[i - 3] = (char *) XSTRING_DATA (args[i]);
      }
    new_argv[nargs - 3] = 0;
  }

  if (NILP (path))
    report_file_error ("Searching for program", Fcons (args[0], Qnil));
  new_argv[0] = (char *) XSTRING_DATA (path);
  
  filefd = open ((char *) XSTRING_DATA (infile), O_RDONLY, 0);
  if (filefd < 0)
    report_file_error ("Opening process input file", Fcons (infile, Qnil));

#ifdef MSDOS
  /* These vars record information from process termination.
     Clear them now before process can possibly terminate,
     to avoid timing error if process terminates soon.  */
  synch_process_death = 0;
  synch_process_retcode = 0;

  if ((outf = egetenv ("TMP")) || (outf = egetenv ("TEMP")))
    strcpy (tempfile = alloca (strlen (outf) + 20), outf);
  else
    {
      tempfile = alloca (20);
      *tempfile = '\0';
    }
  dostounix_filename (tempfile);
  if (*tempfile == '\0' || tempfile[strlen (tempfile) - 1] != '/') 
    strcat (tempfile, "/");
  strcat (tempfile, "detmp.XXX");
  mktemp (tempfile);

  outfilefd = creat (tempfile, S_IREAD | S_IWRITE);
  if (outfilefd < 0)
    {
      close (filefd);
      report_file_error ("Opening process output file",
			 Fcons (tempfile, Qnil));
    }
#endif /* MSDOS */

#ifndef MSDOS
  if (INTP (buffer))
    {
      fd[1] = open (NULL_DEVICE, O_WRONLY, 0);
      fd[0] = -1;
    }
  else
    {
#ifdef WINDOWSNT
      pipe_with_inherited_out (fd);
#else  /* not WINDOWSNT */
      pipe (fd);
#endif /* not WINDOWSNT */
#if 0
      /* Replaced by close_process_descs */
      set_exclusive_use (fd[0]);
#endif
    }
#else /* MSDOS */
  {
    char *outf;

  if (INTP (buffer))
    outf = NULL_DEVICE;
  else 
    {
	/* DOS can't create pipe for interprocess communication, 
	   so redirect child process's standard output to temporary file
	   and later read the file. */
	
      if ((outf = egetenv ("TMP")) || (outf = egetenv ("TEMP")))
	{
	  strcpy (tempfile, outf);
	  dostounix_filename (tempfile);
	}
      else
        *tempfile = '\0';
      if (strlen (tempfile) == 0 || tempfile[strlen (tempfile) - 1] != '/')
	strcat (tempfile, "/");
      strcat (tempfile, "demacs.XXX");
      mktemp (tempfile);
      outf = tempfile;
    }

    if ((fd[1] = creat (outf, S_IREAD | S_IWRITE)) < 0)
      report_file_error ("Can't open temporary file", Qnil);
    fd[0] = -1;
    }
#endif /* MSDOS */

   {
     /* child_setup must clobber environ in systems with true vfork.
	Protect it from permanent change.  */
     REGISTER char **save_environ = environ;
     REGISTER int fd1 = fd[1];
     int fd_error = fd1;
     char **env;

#ifdef EMACS_BTL
    /* when performance monitoring is on, turn it off before the vfork(),
       as the child has no handler for the signal -- when back in the
       parent process, turn it back on if it was really on when you "turned
       it off" */
    int logging_on = cadillac_stop_logging ();
#endif /* EMACS_BTL */

    env = environ;

    /* Record that we're about to create a synchronous process.  */
    synch_process_alive = 1;

    /* These vars record information from process termination.
       Clear them now before process can possibly terminate,
       to avoid timing error if process terminates soon.  */
    synch_process_death = 0;
    synch_process_retcode = 0;

#ifdef MSDOS
    /* ??? Someone who knows MSDOG needs to check whether this properly
       closes all descriptors that it opens.  */
    pid = run_msdos_command (new_argv, current_dir, filefd, outfilefd);
    close (outfilefd);
    fd1 = -1; /* No harm in closing that one!  */
    fd[0] = open (tempfile, NILP (Vbinary_process_output) ? O_TEXT :
			O_BINARY);
    if (fd[0] < 0)
      {
	unlink (tempfile);
	close (filefd);
	report_file_error ("Cannot re-open temporary file", Qnil);
      }
#else /* not MSDOS */
    if (NILP (error_file))
      fd_error = open (NULL_DEVICE, O_WRONLY);
    else if (STRINGP (error_file))
      {
#ifdef DOS_NT
	fd_error = open (XSTRING_DATA (error_file),
			 O_WRONLY | O_TRUNC | O_CREAT | O_TEXT,
			 S_IREAD | S_IWRITE);
#else  /* not DOS_NT */
	fd_error =
	  creat ((CONST char *) XSTRING_DATA (error_file), 0666);
#endif /* not DOS_NT */
      }

    if (fd_error < 0)
      {
	close (filefd);
	close (fd[0]);
	if (fd1 >= 0)
	  close (fd1);
	report_file_error ("Cannot open", Fcons(error_file, Qnil));
      }

    fork_error = Qnil;
#ifdef WINDOWSNT
    pid = child_setup (filefd, fd1, fd_error, new_argv, current_dir);
#else  /* not WINDOWSNT */
    pid = vfork ();

    if (pid == 0)
      {
	if (fd[0] >= 0)
	  close (fd[0]);
	/* This is necessary because some shells may attempt to
	   access the current controlling terminal and will hang
	   if they are run in the background, as will be the case
	   when XEmacs is started in the background.  Martin
	   Buchholz observed this problem running a subprocess
	   that used zsh to call gzip to uncompress an info
	   file. */
	disconnect_controlling_terminal ();
	child_setup (filefd, fd1, fd_error, new_argv,
		     (char *) XSTRING_DATA (current_dir));
      }
#ifdef EMACS_BTL
    else if (logging_on)
      cadillac_start_logging ();
#endif

#endif /* not MSDOS */
#endif /* not WINDOWSNT */

    environ = save_environ;

    /* Close most of our fd's, but not fd[0]
       since we will use that to read input from.  */
    close (filefd);
    if (fd1 >= 0)
      close (fd1);
  }

  if (!NILP (fork_error))
    signal_error (Qfile_error, fork_error);

  if (pid < 0)
    {
      if (fd[0] >= 0)
	close (fd[0]);
      report_file_error ("Doing vfork", Qnil);
    }

  if (INTP (buffer))
    {
      if (fd[0] >= 0)
	close (fd[0]);
#if defined (NO_SUBPROCESSES)
      /* If Emacs has been built with asynchronous subprocess support,
	 we don't need to do this, I think because it will then have
	 the facilities for handling SIGCHLD.  */
      wait_without_blocking ();
#endif /* NO_SUBPROCESSES */
      return Qnil;
    }

  {
    int nread;
    int first = 1;
    int total_read = 0;
    Lisp_Object instream;
    struct gcpro gcpro1;

    /* Enable sending signal if user quits below.  */
    call_process_exited = 0;

#ifdef MSDOS
    /* MSDOS needs different cleanup information.  */
    record_unwind_protect (call_process_cleanup,
                           Fcons (make_int (fd[0]),
                                  build_string (tempfile)));
#else /* not MSDOS */
    record_unwind_protect (call_process_cleanup,
                           Fcons (make_int (fd[0]), make_int (pid)));
#endif /* not MSDOS */

    /* FSFmacs calls Fset_buffer() here.  We don't have to because
       we can insert into buffers other than the current one. */
    if (EQ (buffer, Qt))
      XSETBUFFER (buffer, current_buffer);
    instream = make_filedesc_input_stream (fd[0], 0, -1, LSTR_ALLOW_QUIT);
    GCPRO1 (instream);
    while (1)
      {
	QUIT;
	/* Repeatedly read until we've filled as much as possible
	   of the buffer size we have.  But don't read
	   less than 1024--save that for the next bufferfull.  */

	nread = 0;
	while (nread < bufsize - 1024)
	  {
	    int this_read
	      = Lstream_read (XLSTREAM (instream), bufptr + nread,
			      bufsize - nread);

	    if (this_read < 0)
	      goto give_up;

	    if (this_read == 0)
	      goto give_up_1;

	    nread += this_read;
	  }

      give_up_1:

	/* Now NREAD is the total amount of data in the buffer.  */
	if (nread == 0)
	  break;

	total_read += nread;
	
	if (!NILP (buffer))
	  buffer_insert_raw_string (XBUFFER (buffer), (Bufbyte *) bufptr,
				    nread);

	/* Make the buffer bigger as we continue to read more data,
	   but not past 64k.  */
	if (bufsize < 64 * 1024 && total_read > 32 * bufsize)
	  {
	    bufsize *= 2;
	    bufptr = (char *) alloca (bufsize);
	  }

	if (!NILP (display) && INTERACTIVE)
	  {
	    first = 0;
	    redisplay ();
	  }
      }
  give_up:
    Lstream_close (XLSTREAM (instream));
    UNGCPRO;

    QUIT;
#ifndef MSDOS
    /* Wait for it to terminate, unless it already has.  */
    wait_for_termination (pid);
#endif

    /* Don't kill any children that the subprocess may have left behind
       when exiting.  */
    call_process_exited = 1;
    unbind_to (speccount, Qnil);

    if (synch_process_death)
      return build_string (synch_process_death);
    return make_int (synch_process_retcode);
  }
}

#endif /* VMS */

#ifndef VMS /* VMS version is in vmsproc.c.  */

/* This is the last thing run in a newly forked inferior
   either synchronous or asynchronous.
   Copy descriptors IN, OUT and ERR as descriptors 0, 1 and 2.
   Initialize inferior's priority, pgrp, connected dir and environment.
   then exec another program based on new_argv.

   This function may change environ for the superior process.
   Therefore, the superior process must save and restore the value
   of environ around the vfork and the call to this function.

   ENV is the environment for the subprocess.

   XEmacs: We've removed the SET_PGRP argument because it's already
   done by the callers of child_setup.

   CURRENT_DIR is an elisp string giving the path of the current
   directory the subprocess should have.  Since we can't really signal
   a decent error from within the child, this should be verified as an
   executable directory by the parent.  */

static int relocate_fd (int fd, int min);

void
child_setup (int in, int out, int err, char **new_argv,
	     CONST char *current_dir)
{
#ifdef MSDOS
  /* The MSDOS port of gcc cannot fork, vfork, ... so we must call system
     instead.  */
#else /* not MSDOS */
  char **env;
  char *pwd;
#ifdef WINDOWSNT
  int cpid;
  HANDLE handles[4];
#endif /* WINDOWSNT */

#ifdef SET_EMACS_PRIORITY
  if (emacs_priority != 0)
    nice (- emacs_priority);
#endif

#if !defined (NO_SUBPROCESSES)
  /* Close Emacs's descriptors that this process should not have.  */
  close_process_descs ();
#endif /* not NO_SUBPROCESSES */
  close_load_descs ();

  /* Note that use of alloca is always safe here.  It's obvious for systems
     that do not have true vfork or that have true (stack) alloca.
     If using vfork and C_ALLOCA it is safe because that changes
     the superior's static variables as if the superior had done alloca
     and will be cleaned up in the usual way.  */
  {
    REGISTER int i;

    i = strlen (current_dir);
    pwd = (char *) alloca (i + 6);
    memcpy (pwd, "PWD=", 4);
    memcpy (pwd + 4, current_dir, i);
    i += 4;
    if (!IS_DIRECTORY_SEP (pwd[i - 1]))
      pwd[i++] = DIRECTORY_SEP;
    pwd[i] = 0;

    /* We can't signal an Elisp error here; we're in a vfork.  Since
       the callers check the current directory before forking, this
       should only return an error if the directory's permissions
       are changed between the check and this chdir, but we should
       at least check.  */
    if (chdir (pwd + 4) < 0)
      {
	/* Don't report the chdir error, or ange-ftp.el doesn't work. */
	/* (FSFmacs does _exit (errno) here.) */
	pwd = 0;
      }
    else
      {
	/* Strip trailing "/".  Cretinous *[]&@$#^%@#$% Un*x */
	/* leave "//" (from FSF) */
	while (i > 6 && IS_DIRECTORY_SEP (pwd[i - 1]))
	  pwd[--i] = 0;
      }
  }

  /* Set `env' to a vector of the strings in Vprocess_environment.  */
  {
    REGISTER Lisp_Object tem;
    REGISTER char **new_env;
    REGISTER int new_length;

    new_length = 0;
    for (tem = Vprocess_environment;
	 (CONSP (tem)
	  && STRINGP (XCAR (tem)));
	 tem = XCDR (tem))
      new_length++;

    /* new_length + 2 to include PWD and terminating 0.  */
    env = new_env = (char **) alloca ((new_length + 2) * sizeof (char *));

    /* If we have a PWD envvar and we know the real current directory,
       pass one down, but with corrected value.  */
    if (pwd && getenv ("PWD"))
      *new_env++ = pwd;

    /* Copy the Vprocess_environment strings into new_env.  */
    for (tem = Vprocess_environment;
	 (CONSP (tem)
	  && STRINGP (XCAR (tem)));
	 tem = XCDR (tem))
    {
      char **ep = env;
      char *string = (char *) XSTRING_DATA (XCAR (tem));
      /* See if this string duplicates any string already in the env.
	 If so, don't put it in.
	 When an env var has multiple definitions,
	 we keep the definition that comes first in process-environment.  */
      for (; ep != new_env; ep++)
	{
	  char *p = *ep, *q = string;
	  while (1)
	    {
	      if (*q == 0)
		/* The string is malformed; might as well drop it.  */
		goto duplicate;
	      if (*q != *p)
		break;
	      if (*q == '=')
		goto duplicate;
	      p++, q++;
	    }
	}
      if (pwd && !strncmp ("PWD=", string, 4))
	{
	  *new_env++ = pwd;
	  pwd = 0;
	}
      else
        *new_env++ = string;
    duplicate: ;
    }
    *new_env = 0;
  }
#ifdef WINDOWSNT
  prepare_standard_handles (in, out, err, handles);
#else  /* not WINDOWSNT */
  /* Make sure that in, out, and err are not actually already in
     descriptors zero, one, or two; this could happen if Emacs is
     started with its standard in, out, or error closed, as might
     happen under X.  */
  {
    int oin = in, oout = out;

    /* We have to avoid relocating the same descriptor twice!  */

    in = relocate_fd (in, 3);

    if (out == oin) out = in;
    else            out = relocate_fd (out, 3);

    if      (err == oin)  err = in;
    else if (err == oout) err = out;
    else                  err = relocate_fd (err, 3);
  }

  close (0);
  close (1);
  close (2);

  dup2 (in,  0);
  dup2 (out, 1);
  dup2 (err, 2);
  
  close (in);
  close (out);
  close (err);

  /* I can't think of any reason why child processes need any more
     than the standard 3 file descriptors.  It would be cleaner to
     close just the ones that need to be, but the following brute
     force approach is certainly effective, and not too slow. */
  {
    int fd;
    for (fd=3; fd<=64; fd++)
      {
        close(fd);
      }
  }
#endif /* not WINDOWSNT */

#ifdef vipc
  something missing here;
#endif /* vipc */

#ifdef WINDOWSNT
  /* Spawn the child.  (See ntproc.c:Spawnve).  */
  cpid = spawnve (_P_NOWAIT, new_argv[0], new_argv, env);
  if (cpid == -1)
    /* An error occurred while trying to spawn the process.  */
    report_file_error ("Spawning child process", Qnil);
  reset_standard_handles (in, out, err, handles);
  return cpid;
#else /* not WINDOWSNT */
  /* execvp does not accept an environment arg so the only way
     to pass this environment is to set environ.  Our caller
     is responsible for restoring the ambient value of environ.  */
  environ = env;
  execvp (new_argv[0], new_argv);

  stdout_out ("Cant't exec program %s\n", new_argv[0]);
  _exit (1);
#endif /* not WINDOWSNT */
#endif /* not MSDOS */
}

/* Move the file descriptor FD so that its number is not less than MIN.
   If the file descriptor is moved at all, the original is freed.  */
static int
relocate_fd (int fd, int min)
{
  if (fd >= min)
    return fd;
  else
    {
      int new = dup (fd);
      if (new == -1)
	{
	  stderr_out ("Error while setting up child: %s\n",
		      strerror (errno));
	  _exit (1);
	}
      /* Note that we hold the original FD open while we recurse,
	 to guarantee we'll get a new FD if we need it.  */
      new = relocate_fd (new, min);
      close (fd);
      return new;
    }
}

static int
getenv_internal (CONST Bufbyte *var,
		 Bytecount varlen,
		 Bufbyte **value,
		 Bytecount *valuelen)
{
  Lisp_Object scan;

  for (scan = Vprocess_environment; CONSP (scan); scan = XCDR (scan))
    {
      Lisp_Object entry = XCAR (scan);
      
      if (STRINGP (entry)
	  && XSTRING_LENGTH (entry) > varlen
	  && XSTRING_BYTE (entry, varlen) == '='
#ifdef WINDOWSNT
	  /* NT environment variables are case insensitive.  */
	  && ! memicmp (XSTRING_DATA (entry), var, varlen)
#else  /* not WINDOWSNT */
	  && ! memcmp (XSTRING_DATA (entry), var, varlen)
#endif /* not WINDOWSNT */
	  )
	{
	  *value    = XSTRING_DATA   (entry) + (varlen + 1);
	  *valuelen = XSTRING_LENGTH (entry) - (varlen + 1);
	  return 1;
	}
    }

  return 0;
}

DEFUN ("getenv", Fgetenv, 1, 2, "sEnvironment variable: \np", /*
Return the value of environment variable VAR, as a string.
VAR is a string, the name of the variable.
When invoked interactively, prints the value in the echo area.
*/
       (var, interactivep))
{
  Bufbyte *value;
  Bytecount valuelen;
  Lisp_Object v = Qnil;
  struct gcpro gcpro1;

  CHECK_STRING (var);
  GCPRO1 (v);
  if (getenv_internal (XSTRING_DATA (var), XSTRING_LENGTH (var),
		       &value, &valuelen))
    v = make_string (value, valuelen);
  if (!NILP (interactivep))
    {
      if (NILP (v))
	message ("%s not defined in environment", XSTRING_DATA (var));
      else
	message ("\"%s\"", value);
    }
  RETURN_UNGCPRO (v);
}

/* A version of getenv that consults process_environment, easily
   callable from C.  */
char *
egetenv (CONST char *var)
{
  Bufbyte *value;
  Bytecount valuelen;

  if (getenv_internal ((CONST Bufbyte *) var, strlen (var), &value, &valuelen))
    return (char *) value;
  else
    return 0;
}
#endif /* not VMS */


void
init_callproc (void)
{
  /* This function can GC */
  REGISTER char *sh;
  Lisp_Object tempdir;

  Vprocess_environment = Qnil;
  /* jwz: always initialize Vprocess_environment, so that egetenv() works
     in temacs. */
  {
    char **envp;
    for (envp = environ; envp && *envp; envp++)
      Vprocess_environment = Fcons (build_ext_string (*envp, FORMAT_OS),
				    Vprocess_environment);
  }

  /* jwz: don't do these things when in temacs (this used to be the case by
     virtue of egetenv() always returning 0, but that has been changed).
   */
#ifndef CANNOT_DUMP
  if (!initialized)
    {
      Vdata_directory = Qnil;
      Vsite_directory = Qnil;
      Vdoc_directory  = Qnil;
      Vexec_path      = Qnil;
    }
  else
#endif
    {
      char *data_dir = egetenv ("EMACSDATA");
      char *site_dir = egetenv ("EMACSSITE");
      char *doc_dir  = egetenv ("EMACSDOC");
    
#ifdef PATH_DATA
      if (!data_dir)
	data_dir = (char *) PATH_DATA;
#endif
#ifdef PATH_DOC
      if (!doc_dir)
	doc_dir = (char *) PATH_DOC;
#endif
#ifdef PATH_SITE
      if (!site_dir)
	site_dir = (char *) PATH_SITE;
#endif
    
      if (data_dir)
	Vdata_directory = Ffile_name_as_directory
	  (build_string (data_dir));
      else
	Vdata_directory = Qnil;
      if (doc_dir)
	Vdoc_directory = Ffile_name_as_directory
	  (build_string (doc_dir));
      else
	Vdoc_directory = Qnil;
      if (site_dir)
	Vsite_directory = Ffile_name_as_directory
	  (build_string (site_dir));
      else
	Vsite_directory = Qnil;

      /* Check the EMACSPATH environment variable, defaulting to the
	 PATH_EXEC path from paths.h.  */
      Vexec_path = decode_env_path ("EMACSPATH",
#ifdef PATH_EXEC
				    PATH_EXEC
#else
				    0
#endif
				    );
    }

  if (NILP (Vexec_path))
    Vexec_directory = Qnil;
      else
    Vexec_directory = Ffile_name_as_directory
      (Fcar (Vexec_path));

  if (initialized)
    Vexec_path = nconc2 (decode_env_path ("PATH", 0),
                         Vexec_path);

  if (!NILP (Vexec_directory))
    {
      tempdir = Fdirectory_file_name (Vexec_directory);
      if (access ((char *) XSTRING_DATA (tempdir), 0) < 0)
	{
	  /* If the hard-coded path is bogus, fail silently.
	     This will allow the normal heuristics to make an attempt. */
#if 0
	  warn_when_safe
	    (Qpath, Qwarning,
	     "Warning: machine-dependent data dir (%s) does not exist.\n",
	     XSTRING_DATA (Vexec_directory));
#else
	  Vexec_directory = Qnil;
#endif
	}
    }

  if (!NILP (Vdata_directory))
    {
      tempdir = Fdirectory_file_name (Vdata_directory);
      if (access ((char *) XSTRING_DATA (tempdir), 0) < 0)
	{
	  /* If the hard-coded path is bogus, fail silently.
	     This will allow the normal heuristics to make an attempt. */
#if 0
	  warn_when_safe
	    (Qpath, Qwarning,
	     "Warning: machine-independent data dir (%s) does not exist.\n",
	     XSTRING_DATA (Vdata_directory));
#else
	  Vdata_directory = Qnil;
#endif
	}
    }
  
  if (!NILP (Vsite_directory))
    {
      tempdir = Fdirectory_file_name (Vsite_directory);
      if (access ((char *) XSTRING_DATA (tempdir), 0) < 0)
	{
	  /* If the hard-coded path is bogus, fail silently.
	     This will allow the normal heuristics to make an attempt. */
#if 0
	  warn_when_safe
	    (Qpath, Qwarning,
	     "Warning: machine-independent site dir (%s) does not exist.\n",
	     XSTRING_DATA (Vsite_directory));
#else
	  Vsite_directory = Qnil;
#endif
	}
    }
  
#ifdef PATH_PREFIX
  Vprefix_directory = build_string ((char *) PATH_PREFIX);
#else
  Vprefix_directory = Qnil;
#endif

#ifdef VMS
  Vshell_file_name = build_string ("*dcl*");
#else /* not VMS */
  sh = (char *) egetenv ("SHELL");
#ifdef DOS_NT
  if (!sh) sh = egetenv ("COMSPEC");
  {
    char *tem;
    if (sh)
      {
	tem = (char *) alloca (strlen (sh) + 1);
	sh = dostounix_filename (strcpy (tem, sh));
      }
  }
  Vshell_file_name = build_string (sh ? sh : "/command.com");
#else /* not DOS_NT */
  Vshell_file_name = build_string (sh ? sh : "/bin/sh");
#endif /* not DOS_NT */
#endif /* not VMS */
}

#if 0
void
set_process_environment (void)
{
  REGISTER char **envp;

  Vprocess_environment = Qnil;
#ifndef CANNOT_DUMP
  if (initialized)
#endif
    for (envp = environ; *envp; envp++)
      Vprocess_environment = Fcons (build_string (*envp),
				    Vprocess_environment);
}
#endif /* unused */

void
syms_of_callproc (void)
{
#ifndef VMS
  DEFSUBR (Fcall_process_internal);
  DEFSUBR (Fgetenv);
#endif
}

void
vars_of_callproc (void)
{
  /* This function can GC */
#ifdef DOS_NT
  DEFVAR_LISP ("binary-process-input", &Vbinary_process_input /*
*If non-nil then new subprocesses are assumed to take binary input.
*/ );
  Vbinary_process_input = Qnil;

  DEFVAR_LISP ("binary-process-output", &Vbinary_process_output /*
*If non-nil then new subprocesses are assumed to produce binary output.
*/ );
  Vbinary_process_output = Qnil;
#endif /* DOS_NT */

  DEFVAR_LISP ("shell-file-name", &Vshell_file_name /*
*File name to load inferior shells from.
Initialized from the SHELL environment variable.
*/ );

  DEFVAR_LISP ("exec-path", &Vexec_path /*
*List of directories to search programs to run in subprocesses.
Each element is a string (directory name) or nil (try default directory).
*/ );

  DEFVAR_LISP ("exec-directory", &Vexec_directory /*
Directory of architecture-dependent files that come with XEmacs,
especially executable programs intended for Emacs to invoke.
*/ );

  DEFVAR_LISP ("data-directory", &Vdata_directory /*
Directory of architecture-independent files that come with XEmacs,
intended for Emacs to use.
*/ );

  DEFVAR_LISP ("site-directory", &Vsite_directory /*
Directory of architecture-independent files that do not come with XEmacs,
intended for Emacs to use.
*/ );

  /* FSF puts the DOC file into data-directory.  They do a bunch of
     contortions to attempt to put everything into the DOC file
     whether the support is there or not. */
  DEFVAR_LISP ("doc-directory", &Vdoc_directory /*
Directory containing the DOC file that comes with XEmacs.
This is usually the same as exec-directory.
*/ );

  DEFVAR_LISP ("prefix-directory", &Vprefix_directory /*
The default directory under which XEmacs is installed.
*/ );

  DEFVAR_LISP ("process-environment", &Vprocess_environment /*
List of environment variables for subprocesses to inherit.
Each element should be a string of the form ENVVARNAME=VALUE.
The environment which Emacs inherits is placed in this variable
when Emacs starts.
*/ );
}

void
complex_vars_of_callproc (void)
{
  DEFVAR_LISP ("configure-info-directory", &Vconfigure_info_directory /*
For internal use by the build procedure only.
This is the name of the directory in which the build procedure installed
Emacs's info files; the default value for Info-default-directory-list
includes this.
*/ );
#ifdef PATH_INFO
  Vconfigure_info_directory =
    Ffile_name_as_directory (build_string (PATH_INFO));
#else
  Vconfigure_info_directory = Qnil;
#endif
}
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.