[506253]: src / code / unix.lisp Maximize Restore History

Download this file

unix.lisp    1004 lines (892 with data), 37.3 kB

   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
;;;; This file contains Unix support that SBCL needs to implement
;;;; itself. It's derived from Peter Van Eynde's unix-glibc2.lisp for
;;;; CMU CL, which was derived from CMU CL unix.lisp 1.56. But those
;;;; files aspired to be complete Unix interfaces exported to the end
;;;; user, while this file aims to be as simple as possible and is not
;;;; intended for the end user.
;;;;
;;;; FIXME: The old CMU CL unix.lisp code was implemented as hand
;;;; transcriptions from Unix headers into Lisp. It appears that this was as
;;;; unmaintainable in practice as you'd expect in theory, so I really really
;;;; don't want to do that. It'd be good to implement the various system calls
;;;; as C code implemented using the Unix header files, and have their
;;;; interface back to SBCL code be characterized by things like "32-bit-wide
;;;; int" which are already in the interface between the runtime
;;;; executable and the SBCL lisp code.
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;;;;
;;;; This software is derived from the CMU CL system, which was
;;;; written at Carnegie Mellon University and released into the
;;;; public domain. The software is in the public domain and is
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.
(in-package "SB!UNIX")
(/show0 "unix.lisp 21")
(defmacro def-enum (inc cur &rest names)
(flet ((defform (name)
(prog1 (when name `(defconstant ,name ,cur))
(setf cur (funcall inc cur 1)))))
`(progn ,@(mapcar #'defform names))))
;;; Given a C-level zero-terminated array of C strings, return a
;;; corresponding Lisp-level list of SIMPLE-STRINGs.
(defun c-strings->string-list (c-strings)
(declare (type (alien (* c-string)) c-strings))
(let ((reversed-result nil))
(dotimes (i most-positive-fixnum (error "argh! can't happen"))
(declare (type index i))
(let ((c-string (deref c-strings i)))
(if c-string
(push c-string reversed-result)
(return (nreverse reversed-result)))))))
;;;; Lisp types used by syscalls
(deftype unix-pathname () 'simple-base-string)
(deftype unix-fd () `(integer 0 ,most-positive-fixnum))
(deftype unix-file-mode () '(unsigned-byte 32))
(deftype unix-pid () '(unsigned-byte 32))
(deftype unix-uid () '(unsigned-byte 32))
(deftype unix-gid () '(unsigned-byte 32))
;;;; system calls
(/show0 "unix.lisp 74")
;;; FIXME: The various FOO-SYSCALL-BAR macros, and perhaps some other
;;; macros in this file, are only used in this file, and could be
;;; implemented using SB!XC:DEFMACRO wrapped in EVAL-WHEN.
(defmacro syscall ((name &rest arg-types) success-form &rest args)
`(let ((result (alien-funcall (extern-alien ,name (function int ,@arg-types))
,@args)))
(if (minusp result)
(values nil (get-errno))
,success-form)))
;;; This is like SYSCALL, but if it fails, signal an error instead of
;;; returning error codes. Should only be used for syscalls that will
;;; never really get an error.
(defmacro syscall* ((name &rest arg-types) success-form &rest args)
`(let ((result (alien-funcall (extern-alien ,name (function int ,@arg-types))
,@args)))
(if (minusp result)
(error "Syscall ~A failed: ~A" ,name (strerror))
,success-form)))
(/show0 "unix.lisp 109")
(defmacro void-syscall ((name &rest arg-types) &rest args)
`(syscall (,name ,@arg-types) (values t 0) ,@args))
(defmacro int-syscall ((name &rest arg-types) &rest args)
`(syscall (,name ,@arg-types) (values result 0) ,@args))
;;;; hacking the Unix environment
(define-alien-routine ("getenv" posix-getenv) c-string
"Return the \"value\" part of the environment string \"name=value\" which
corresponds to NAME, or NIL if there is none."
(name c-string))
;;; from stdio.h
;;; Rename the file with string NAME1 to the string NAME2. NIL and an
;;; error code is returned if an error occurs.
(defun unix-rename (name1 name2)
(declare (type unix-pathname name1 name2))
(void-syscall ("rename" c-string c-string) name1 name2))
;;; from sys/types.h and gnu/types.h
(/show0 "unix.lisp 220")
;;; FIXME: We shouldn't hand-copy types from header files into Lisp
;;; like this unless we have extreme provocation. Reading directories
;;; is not extreme enough, since it doesn't need to be blindingly
;;; fast: we can just implement those functions in C as a wrapper
;;; layer.
(define-alien-type fd-mask unsigned-long)
(eval-when (:compile-toplevel :load-toplevel :execute)
(defconstant fd-setsize 1024))
(define-alien-type nil
(struct fd-set
(fds-bits (array fd-mask #.(/ fd-setsize 32)))))
(/show0 "unix.lisp 304")
;;;; fcntl.h
;;;;
;;;; POSIX Standard: 6.5 File Control Operations <fcntl.h>
;;; Open the file whose pathname is specified by PATH for reading
;;; and/or writing as specified by the FLAGS argument. Various FLAGS
;;; masks (O_RDONLY etc.) are defined in fcntlbits.h.
;;;
;;; If the O_CREAT flag is specified, then the file is created with a
;;; permission of argument MODE if the file doesn't exist. An integer
;;; file descriptor is returned by UNIX-OPEN.
(defun unix-open (path flags mode)
(declare (type unix-pathname path)
(type fixnum flags)
(type unix-file-mode mode))
(int-syscall ("open" c-string int int) path flags mode))
;;; UNIX-CLOSE accepts a file descriptor and attempts to close the file
;;; associated with it.
(/show0 "unix.lisp 391")
(defun unix-close (fd)
(declare (type unix-fd fd))
(void-syscall ("close" int) fd))
;;;; timebits.h
;; A time value that is accurate to the nearest
;; microsecond but also has a range of years.
(define-alien-type nil
(struct timeval
(tv-sec time-t) ; seconds
(tv-usec time-t))) ; and microseconds
;;;; resourcebits.h
(defconstant rusage_self 0) ; the calling process
(defconstant rusage_children -1) ; terminated child processes
(defconstant rusage_both -2)
(define-alien-type nil
(struct rusage
(ru-utime (struct timeval)) ; user time used
(ru-stime (struct timeval)) ; system time used.
(ru-maxrss long) ; maximum resident set size (in kilobytes)
(ru-ixrss long) ; integral shared memory size
(ru-idrss long) ; integral unshared data size
(ru-isrss long) ; integral unshared stack size
(ru-minflt long) ; page reclaims
(ru-majflt long) ; page faults
(ru-nswap long) ; swaps
(ru-inblock long) ; block input operations
(ru-oublock long) ; block output operations
(ru-msgsnd long) ; messages sent
(ru-msgrcv long) ; messages received
(ru-nsignals long) ; signals received
(ru-nvcsw long) ; voluntary context switches
(ru-nivcsw long))) ; involuntary context switches
;;;; unistd.h
;;; Given a file path (a string) and one of four constant modes,
;;; return T if the file is accessible with that mode and NIL if not.
;;; When NIL, also return an errno value with NIL which tells why the
;;; file was not accessible.
;;;
;;; The access modes are:
;;; r_ok Read permission.
;;; w_ok Write permission.
;;; x_ok Execute permission.
;;; f_ok Presence of file.
(defun unix-access (path mode)
(declare (type unix-pathname path)
(type (mod 8) mode))
(void-syscall ("access" c-string int) path mode))
;;; values for the second argument to UNIX-LSEEK
(defconstant l_set 0) ; to set the file pointer
(defconstant l_incr 1) ; to increment the file pointer
(defconstant l_xtnd 2) ; to extend the file size
;;; Is a stream interactive?
(defun unix-isatty (fd)
(declare (type unix-fd fd))
(int-syscall ("isatty" int) fd))
(defun unix-lseek (fd offset whence)
"Unix-lseek accepts a file descriptor and moves the file pointer by
OFFSET octets. Whence can be any of the following:
L_SET Set the file pointer.
L_INCR Increment the file pointer.
L_XTND Extend the file size.
"
(declare (type unix-fd fd)
(type (integer 0 2) whence))
(let ((result (alien-funcall (extern-alien "lseek" (function off-t int off-t int))
fd offset whence)))
(if (minusp result )
(values nil (get-errno))
(values result 0))))
;;; UNIX-READ accepts a file descriptor, a buffer, and the length to read.
;;; It attempts to read len bytes from the device associated with fd
;;; and store them into the buffer. It returns the actual number of
;;; bytes read.
(defun unix-read (fd buf len)
(declare (type unix-fd fd)
(type (unsigned-byte 32) len))
(int-syscall ("read" int (* char) int) fd buf len))
;;; UNIX-WRITE accepts a file descriptor, a buffer, an offset, and the
;;; length to write. It attempts to write len bytes to the device
;;; associated with fd from the the buffer starting at offset. It returns
;;; the actual number of bytes written.
(defun unix-write (fd buf offset len)
(declare (type unix-fd fd)
(type (unsigned-byte 32) offset len))
(int-syscall ("write" int (* char) int)
fd
(with-alien ((ptr (* char) (etypecase buf
((simple-array * (*))
(vector-sap buf))
(system-area-pointer
buf))))
(addr (deref ptr offset)))
len))
;;; Set up a unix-piping mechanism consisting of an input pipe and an
;;; output pipe. Return two values: if no error occurred the first
;;; value is the pipe to be read from and the second is can be written
;;; to. If an error occurred the first value is NIL and the second the
;;; unix error code.
(defun unix-pipe ()
(with-alien ((fds (array int 2)))
(syscall ("pipe" (* int))
(values (deref fds 0) (deref fds 1))
(cast fds (* int)))))
(defun unix-mkdir (name mode)
(declare (type unix-pathname name)
(type unix-file-mode mode))
(void-syscall ("mkdir" c-string int) name mode))
;;; Given a C char* pointer allocated by malloc(), free it and return a
;;; corresponding Lisp string (or return NIL if the pointer is a C NULL).
(defun newcharstar-string (newcharstar)
(declare (type (alien (* char)) newcharstar))
(if (null-alien newcharstar)
nil
(prog1
(cast newcharstar c-string)
(free-alien newcharstar))))
;;; Return the Unix current directory as a SIMPLE-STRING, in the
;;; style returned by getcwd() (no trailing slash character).
(defun posix-getcwd ()
;; This implementation relies on a BSD/Linux extension to getcwd()
;; behavior, automatically allocating memory when a null buffer
;; pointer is used. On a system which doesn't support that
;; extension, it'll have to be rewritten somehow.
;;
;; SunOS and OSF/1 provide almost as useful an extension: if given a null
;; buffer pointer, it will automatically allocate size space. The
;; KLUDGE in this solution arises because we have just read off
;; PATH_MAX+1 from the Solaris header files and stuck it in here as
;; a constant. Going the grovel_headers route doesn't seem to be
;; helpful, either, as Solaris doesn't export PATH_MAX from
;; unistd.h.
#!-(or linux openbsd freebsd sunos osf1 darwin) (,stub,)
#!+(or linux openbsd freebsd sunos osf1 darwin)
(or (newcharstar-string (alien-funcall (extern-alien "getcwd"
(function (* char)
(* char)
size-t))
nil
#!+(or linux openbsd freebsd darwin) 0
#!+(or sunos osf1) 1025))
(simple-perror "getcwd")))
;;; Return the Unix current directory as a SIMPLE-STRING terminated
;;; by a slash character.
(defun posix-getcwd/ ()
(concatenate 'string (posix-getcwd) "/"))
;;; Convert at the UNIX level from a possibly relative filename to
;;; an absolute filename.
;;;
;;; FIXME: Do we still need this even as we switch to
;;; *DEFAULT-PATHNAME-DEFAULTS*? I think maybe we do, since it seems
;;; to be valid for the user to set *DEFAULT-PATHNAME-DEFAULTS* to
;;; have a NIL directory component, and then this'd be the only way to
;;; interpret a relative directory specification. But I don't find the
;;; ANSI pathname documentation to be a model of clarity. Maybe
;;; someone who understands it better can take a look at this.. -- WHN
(defun unix-maybe-prepend-current-directory (name)
(declare (simple-string name))
(if (and (> (length name) 0) (char= (schar name 0) #\/))
name
(concatenate 'simple-string (posix-getcwd/) name)))
;;; Duplicate an existing file descriptor (given as the argument) and
;;; return it. If FD is not a valid file descriptor, NIL and an error
;;; number are returned.
(defun unix-dup (fd)
(declare (type unix-fd fd))
(int-syscall ("dup" int) fd))
;;; Terminate the current process with an optional error code. If
;;; successful, the call doesn't return. If unsuccessful, the call
;;; returns NIL and an error number.
(defun unix-exit (&optional (code 0))
(declare (type (signed-byte 32) code))
(void-syscall ("exit" int) code))
;;; Return the process id of the current process.
(define-alien-routine ("getpid" unix-getpid) int)
;;; Return the real user id associated with the current process.
(define-alien-routine ("getuid" unix-getuid) int)
;;; Translate a user id into a login name.
(defun uid-username (uid)
(or (newcharstar-string (alien-funcall (extern-alien "uid_username"
(function (* char) int))
uid))
(error "found no match for Unix uid=~S" uid)))
;;; Return the namestring of the home directory, being careful to
;;; include a trailing #\/
(defun uid-homedir (uid)
(or (newcharstar-string (alien-funcall (extern-alien "uid_homedir"
(function (* char) int))
uid))
(error "failed to resolve home directory for Unix uid=~S" uid)))
;;; Invoke readlink(2) on the file name specified by PATH. Return
;;; (VALUES LINKSTRING NIL) on success, or (VALUES NIL ERRNO) on
;;; failure.
(defun unix-readlink (path)
(declare (type unix-pathname path))
(with-alien ((ptr (* char)
(alien-funcall (extern-alien
"wrapped_readlink"
(function (* char) c-string))
path)))
(if (null-alien ptr)
(values nil (get-errno))
(multiple-value-prog1
(values (with-alien ((c-string c-string ptr)) c-string)
nil)
(free-alien ptr)))))
;;; UNIX-UNLINK accepts a name and deletes the directory entry for that
;;; name and the file if this is the last link.
(defun unix-unlink (name)
(declare (type unix-pathname name))
(void-syscall ("unlink" c-string) name))
;;; Return the name of the host machine as a string.
(defun unix-gethostname ()
(with-alien ((buf (array char 256)))
(syscall ("gethostname" (* char) int)
(cast buf c-string)
(cast buf (* char)) 256)))
;;; Write the core image of the file described by FD to disk.
(defun unix-fsync (fd)
(declare (type unix-fd fd))
(void-syscall ("fsync" int) fd))
(defun unix-setsid ()
(int-syscall ("setsid")))
;;;; sys/ioctl.h
;;; UNIX-IOCTL performs a variety of operations on open i/o
;;; descriptors. See the UNIX Programmer's Manual for more
;;; information.
(defun unix-ioctl (fd cmd arg)
(declare (type unix-fd fd)
(type (signed-byte 32) cmd))
(void-syscall ("ioctl" int int (* char)) fd cmd arg))
;;;; sys/resource.h
;;; FIXME: All we seem to need is the RUSAGE_SELF version of this.
;;;
;;; This is like getrusage(2), except it returns only the system and
;;; user time, and returns the seconds and microseconds as separate
;;; values.
#!-sb-fluid (declaim (inline unix-fast-getrusage))
(defun unix-fast-getrusage (who)
(declare (values (member t)
(unsigned-byte 31) (integer 0 1000000)
(unsigned-byte 31) (integer 0 1000000)))
(with-alien ((usage (struct rusage)))
(syscall* ("getrusage" int (* (struct rusage)))
(values t
(slot (slot usage 'ru-utime) 'tv-sec)
(slot (slot usage 'ru-utime) 'tv-usec)
(slot (slot usage 'ru-stime) 'tv-sec)
(slot (slot usage 'ru-stime) 'tv-usec))
who (addr usage))))
;;; Return information about the resource usage of the process
;;; specified by WHO. WHO can be either the current process
;;; (rusage_self) or all of the terminated child processes
;;; (rusage_children). NIL and an error number is returned if the call
;;; fails.
(defun unix-getrusage (who)
(with-alien ((usage (struct rusage)))
(syscall ("getrusage" int (* (struct rusage)))
(values t
(+ (* (slot (slot usage 'ru-utime) 'tv-sec) 1000000)
(slot (slot usage 'ru-utime) 'tv-usec))
(+ (* (slot (slot usage 'ru-stime) 'tv-sec) 1000000)
(slot (slot usage 'ru-stime) 'tv-usec))
(slot usage 'ru-maxrss)
(slot usage 'ru-ixrss)
(slot usage 'ru-idrss)
(slot usage 'ru-isrss)
(slot usage 'ru-minflt)
(slot usage 'ru-majflt)
(slot usage 'ru-nswap)
(slot usage 'ru-inblock)
(slot usage 'ru-oublock)
(slot usage 'ru-msgsnd)
(slot usage 'ru-msgrcv)
(slot usage 'ru-nsignals)
(slot usage 'ru-nvcsw)
(slot usage 'ru-nivcsw))
who (addr usage))))
;;;; sys/select.h
;;;; FIXME: Why have both UNIX-SELECT and UNIX-FAST-SELECT?
;;; Perform the UNIX select(2) system call.
(declaim (inline unix-fast-select)) ; (used to be a macro in CMU CL)
(defun unix-fast-select (num-descriptors
read-fds write-fds exception-fds
timeout-secs &optional (timeout-usecs 0))
(declare (type (integer 0 #.fd-setsize) num-descriptors)
(type (or (alien (* (struct fd-set))) null)
read-fds write-fds exception-fds)
(type (or null (unsigned-byte 31)) timeout-secs)
(type (unsigned-byte 31) timeout-usecs))
;; FIXME: CMU CL had
;; (declare (optimize (speed 3) (safety 0) (inhibit-warnings 3)))
;; here. Is that important for SBCL? If so, why? Profiling might tell us..
(with-alien ((tv (struct timeval)))
(when timeout-secs
(setf (slot tv 'tv-sec) timeout-secs)
(setf (slot tv 'tv-usec) timeout-usecs))
(int-syscall ("select" int (* (struct fd-set)) (* (struct fd-set))
(* (struct fd-set)) (* (struct timeval)))
num-descriptors read-fds write-fds exception-fds
(if timeout-secs (alien-sap (addr tv)) (int-sap 0)))))
;;; UNIX-SELECT accepts sets of file descriptors and waits for an event
;;; to happen on one of them or to time out.
(defmacro num-to-fd-set (fdset num)
`(if (fixnump ,num)
(progn
(setf (deref (slot ,fdset 'fds-bits) 0) ,num)
,@(loop for index upfrom 1 below (/ fd-setsize 32)
collect `(setf (deref (slot ,fdset 'fds-bits) ,index) 0)))
(progn
,@(loop for index upfrom 0 below (/ fd-setsize 32)
collect `(setf (deref (slot ,fdset 'fds-bits) ,index)
(ldb (byte 32 ,(* index 32)) ,num))))))
(defmacro fd-set-to-num (nfds fdset)
`(if (<= ,nfds 32)
(deref (slot ,fdset 'fds-bits) 0)
(+ ,@(loop for index upfrom 0 below (/ fd-setsize 32)
collect `(ash (deref (slot ,fdset 'fds-bits) ,index)
,(* index 32))))))
;;; Examine the sets of descriptors passed as arguments to see whether
;;; they are ready for reading and writing. See the UNIX Programmer's
;;; Manual for more information.
(defun unix-select (nfds rdfds wrfds xpfds to-secs &optional (to-usecs 0))
(declare (type (integer 0 #.FD-SETSIZE) nfds)
(type unsigned-byte rdfds wrfds xpfds)
(type (or (unsigned-byte 31) null) to-secs)
(type (unsigned-byte 31) to-usecs)
(optimize (speed 3) (safety 0) (inhibit-warnings 3)))
(with-alien ((tv (struct timeval))
(rdf (struct fd-set))
(wrf (struct fd-set))
(xpf (struct fd-set)))
(when to-secs
(setf (slot tv 'tv-sec) to-secs)
(setf (slot tv 'tv-usec) to-usecs))
(num-to-fd-set rdf rdfds)
(num-to-fd-set wrf wrfds)
(num-to-fd-set xpf xpfds)
(macrolet ((frob (lispvar alienvar)
`(if (zerop ,lispvar)
(int-sap 0)
(alien-sap (addr ,alienvar)))))
(syscall ("select" int (* (struct fd-set)) (* (struct fd-set))
(* (struct fd-set)) (* (struct timeval)))
(values result
(fd-set-to-num nfds rdf)
(fd-set-to-num nfds wrf)
(fd-set-to-num nfds xpf))
nfds (frob rdfds rdf) (frob wrfds wrf) (frob xpfds xpf)
(if to-secs (alien-sap (addr tv)) (int-sap 0))))))
;;;; sys/stat.h
;;; This is a structure defined in src/runtime/wrap.c, to look
;;; basically like "struct stat" according to stat(2). It may not
;;; actually correspond to the real in-memory stat structure that the
;;; syscall uses, and that's OK. Linux in particular is packed full of
;;; stat macros, and trying to keep Lisp code in correspondence with
;;; it is more pain than it's worth, so we just let our C runtime
;;; synthesize a nice consistent structure for us.
;;;
;;; Note that st-dev is a long, not a dev-t. This is because dev-t on
;;; linux 32 bit archs is a 64 bit quantity, but alien doesn's support
;;; those. We don't actually access that field anywhere, though, so
;;; until we can get 64 bit alien support it'll do. Also note that
;;; st_size is a long, not an off-t, because off-t is a 64-bit
;;; quantity on Alpha. And FIXME: "No one would want a file length
;;; longer than 32 bits anyway, right?":-|
(define-alien-type nil
(struct wrapped_stat
(st-dev unsigned-long) ; would be dev-t in a real stat
(st-ino ino-t)
(st-mode mode-t)
(st-nlink nlink-t)
(st-uid uid-t)
(st-gid gid-t)
(st-rdev unsigned-long) ; would be dev-t in a real stat
(st-size unsigned-long) ; would be off-t in a real stat
(st-blksize unsigned-long)
(st-blocks unsigned-long)
(st-atime time-t)
(st-mtime time-t)
(st-ctime time-t)))
;;; shared C-struct-to-multiple-VALUES conversion for the stat(2)
;;; family of Unix system calls
;;;
;;; FIXME: I think this should probably not be INLINE. However, when
;;; this was not inline, it seemed to cause memory corruption
;;; problems. My first guess is that it's a bug in the FFI code, where
;;; the WITH-ALIEN expansion doesn't deal well with being wrapped
;;; around a call to a function returning >10 values. But I didn't try
;;; to figure it out, just inlined it as a quick fix. Perhaps someone
;;; who's motivated to debug the FFI code can go over the DISASSEMBLE
;;; output in the not-inlined case and see whether there's a problem,
;;; and maybe even find a fix..
(declaim (inline %extract-stat-results))
(defun %extract-stat-results (wrapped-stat)
(declare (type (alien (* (struct wrapped_stat))) wrapped-stat))
(values t
(slot wrapped-stat 'st-dev)
(slot wrapped-stat 'st-ino)
(slot wrapped-stat 'st-mode)
(slot wrapped-stat 'st-nlink)
(slot wrapped-stat 'st-uid)
(slot wrapped-stat 'st-gid)
(slot wrapped-stat 'st-rdev)
(slot wrapped-stat 'st-size)
(slot wrapped-stat 'st-atime)
(slot wrapped-stat 'st-mtime)
(slot wrapped-stat 'st-ctime)
(slot wrapped-stat 'st-blksize)
(slot wrapped-stat 'st-blocks)))
;;; Unix system calls in the stat(2) family are handled by calls to
;;; C-level wrapper functions which copy all the raw "struct stat"
;;; slots into the system-independent wrapped_stat format.
;;; stat(2) <-> stat_wrapper()
;;; fstat(2) <-> fstat_wrapper()
;;; lstat(2) <-> lstat_wrapper()
(defun unix-stat (name)
(declare (type unix-pathname name))
(with-alien ((buf (struct wrapped_stat)))
(syscall ("stat_wrapper" c-string (* (struct wrapped_stat)))
(%extract-stat-results (addr buf))
name (addr buf))))
(defun unix-lstat (name)
(declare (type unix-pathname name))
(with-alien ((buf (struct wrapped_stat)))
(syscall ("lstat_wrapper" c-string (* (struct wrapped_stat)))
(%extract-stat-results (addr buf))
name (addr buf))))
(defun unix-fstat (fd)
(declare (type unix-fd fd))
(with-alien ((buf (struct wrapped_stat)))
(syscall ("fstat_wrapper" int (* (struct wrapped_stat)))
(%extract-stat-results (addr buf))
fd (addr buf))))
;;;; time.h
;; the POSIX.4 structure for a time value. This is like a "struct
;; timeval" but has nanoseconds instead of microseconds.
(define-alien-type nil
(struct timespec
(tv-sec long) ; seconds
(tv-nsec long))) ; nanoseconds
;; used by other time functions
(define-alien-type nil
(struct tm
(tm-sec int) ; Seconds. [0-60] (1 leap second)
(tm-min int) ; Minutes. [0-59]
(tm-hour int) ; Hours. [0-23]
(tm-mday int) ; Day. [1-31]
(tm-mon int) ; Month. [0-11]
(tm-year int) ; Year - 1900.
(tm-wday int) ; Day of week. [0-6]
(tm-yday int) ; Days in year. [0-365]
(tm-isdst int) ; DST. [-1/0/1]
(tm-gmtoff long) ; Seconds east of UTC.
(tm-zone c-string))) ; Timezone abbreviation.
(define-alien-routine get-timezone sb!alien:void
(when sb!alien:long :in)
(minutes-west sb!alien:int :out)
(daylight-savings-p sb!alien:boolean :out))
(defun unix-get-minutes-west (secs)
(multiple-value-bind (ignore minutes dst) (get-timezone secs)
(declare (ignore ignore) (ignore dst))
(values minutes)))
(defun unix-get-timezone (secs)
(multiple-value-bind (ignore minutes dst) (get-timezone secs)
(declare (ignore ignore) (ignore minutes))
(values (deref unix-tzname (if dst 1 0)))))
;;;; sys/time.h
;;; Structure crudely representing a timezone. KLUDGE: This is
;;; obsolete and should never be used.
(define-alien-type nil
(struct timezone
(tz-minuteswest int) ; minutes west of Greenwich
(tz-dsttime int))) ; type of dst correction
;;; If it works, UNIX-GETTIMEOFDAY returns 5 values: T, the seconds
;;; and microseconds of the current time of day, the timezone (in
;;; minutes west of Greenwich), and a daylight-savings flag. If it
;;; doesn't work, it returns NIL and the errno.
#!-sb-fluid (declaim (inline unix-gettimeofday))
(defun unix-gettimeofday ()
(with-alien ((tv (struct timeval))
(tz (struct timezone)))
(syscall* ("gettimeofday" (* (struct timeval))
(* (struct timezone)))
(values T
(slot tv 'tv-sec)
(slot tv 'tv-usec)
(slot tz 'tz-minuteswest)
(slot tz 'tz-dsttime))
(addr tv)
(addr tz))))
;; Type of the second argument to `getitimer' and
;; the second and third arguments `setitimer'.
(define-alien-type nil
(struct itimerval
(it-interval (struct timeval)) ; timer interval
(it-value (struct timeval)))) ; current value
(defconstant ITIMER-REAL 0)
(defconstant ITIMER-VIRTUAL 1)
(defconstant ITIMER-PROF 2)
(defun unix-getitimer(which)
"Unix-getitimer returns the INTERVAL and VALUE slots of one of
three system timers (:real :virtual or :profile). On success,
unix-getitimer returns 5 values,
T, it-interval-secs, it-interval-usec, it-value-secs, it-value-usec."
(declare (type (member :real :virtual :profile) which)
(values t
(unsigned-byte 29) (mod 1000000)
(unsigned-byte 29) (mod 1000000)))
(let ((which (ecase which
(:real ITIMER-REAL)
(:virtual ITIMER-VIRTUAL)
(:profile ITIMER-PROF))))
(with-alien ((itv (struct itimerval)))
(syscall* ("getitimer" int (* (struct itimerval)))
(values T
(slot (slot itv 'it-interval) 'tv-sec)
(slot (slot itv 'it-interval) 'tv-usec)
(slot (slot itv 'it-value) 'tv-sec)
(slot (slot itv 'it-value) 'tv-usec))
which (alien-sap (addr itv))))))
(defun unix-setitimer (which int-secs int-usec val-secs val-usec)
" Unix-setitimer sets the INTERVAL and VALUE slots of one of
three system timers (:real :virtual or :profile). A SIGALRM signal
will be delivered VALUE <seconds+microseconds> from now. INTERVAL,
when non-zero, is <seconds+microseconds> to be loaded each time
the timer expires. Setting INTERVAL and VALUE to zero disables
the timer. See the Unix man page for more details. On success,
unix-setitimer returns the old contents of the INTERVAL and VALUE
slots as in unix-getitimer."
(declare (type (member :real :virtual :profile) which)
(type (unsigned-byte 29) int-secs val-secs)
(type (integer 0 (1000000)) int-usec val-usec)
(values t
(unsigned-byte 29) (mod 1000000)
(unsigned-byte 29) (mod 1000000)))
(let ((which (ecase which
(:real ITIMER-REAL)
(:virtual ITIMER-VIRTUAL)
(:profile ITIMER-PROF))))
(with-alien ((itvn (struct itimerval))
(itvo (struct itimerval)))
(setf (slot (slot itvn 'it-interval) 'tv-sec ) int-secs
(slot (slot itvn 'it-interval) 'tv-usec) int-usec
(slot (slot itvn 'it-value ) 'tv-sec ) val-secs
(slot (slot itvn 'it-value ) 'tv-usec) val-usec)
(syscall* ("setitimer" int (* (struct timeval))(* (struct timeval)))
(values T
(slot (slot itvo 'it-interval) 'tv-sec)
(slot (slot itvo 'it-interval) 'tv-usec)
(slot (slot itvo 'it-value) 'tv-sec)
(slot (slot itvo 'it-value) 'tv-usec))
which (alien-sap (addr itvn))(alien-sap (addr itvo))))))
(defmacro sb!ext::with-timeout (expires &body body)
"Execute the body, interrupting it with a SIGALRM after at least
EXPIRES seconds have passed. Uses Unix setitimer(), restoring any
previous timer after the body has finished executing"
(with-unique-names (saved-seconds saved-useconds s u)
`(let (- ,saved-seconds ,saved-useconds)
(multiple-value-setq (- - - ,saved-seconds ,saved-useconds)
(unix-getitimer :real))
(multiple-value-bind (,s ,u) (floor ,expires)
(setf ,u (floor (* ,u 1000000)))
(if (and (> ,expires 0)
(or (and (zerop ,saved-seconds) (zerop ,saved-useconds))
(> ,saved-seconds ,s)
(and (= ,saved-seconds ,s)
(> ,saved-useconds ,u))))
(unwind-protect
(progn
(unix-setitimer :real 0 0 ,s ,u)
,@body)
(unix-setitimer :real 0 0 ,saved-seconds ,saved-useconds))
,@body)))))
(defconstant ENOENT 2) ; Unix error code, "No such file or directory"
(defconstant EINTR 4) ; Unix error code, "Interrupted system call"
(defconstant EIO 5) ; Unix error code, "I/O error"
(defconstant EEXIST 17) ; Unix error code, "File exists"
(defconstant ESPIPE 29) ; Unix error code, "Illegal seek"
(defconstant EWOULDBLOCK 11) ; Unix error code, "Operation would block"
;;; FIXME: Many Unix error code definitions were deleted from the old
;;; CMU CL source code here, but not in the exports of SB-UNIX. I
;;; (WHN) hope that someday I'll figure out an automatic way to detect
;;; unused symbols in package exports, but if I don't, there are
;;; enough of them all in one place here that they should probably be
;;; removed by hand.
;;;; support routines for dealing with Unix pathnames
(defun unix-file-kind (name &optional check-for-links)
#!+sb-doc
"Return either :FILE, :DIRECTORY, :LINK, :SPECIAL, or NIL."
(declare (simple-base-string name))
(multiple-value-bind (res dev ino mode)
(if check-for-links (unix-lstat name) (unix-stat name))
(declare (type (or fixnum null) mode)
(ignore dev ino))
(when res
(let ((kind (logand mode s-ifmt)))
(cond ((eql kind s-ifdir) :directory)
((eql kind s-ifreg) :file)
((eql kind s-iflnk) :link)
(t :special))))))
;;; Is the Unix pathname PATHNAME relative, instead of absolute? (E.g.
;;; "passwd" or "etc/passwd" instead of "/etc/passwd"?)
(defun relative-unix-pathname? (pathname)
(declare (type simple-string pathname))
(or (zerop (length pathname))
(char/= (schar pathname 0) #\/)))
;;; Return PATHNAME with all symbolic links resolved. PATHNAME should
;;; already be a complete absolute Unix pathname, since at least in
;;; sbcl-0.6.12.36 we're called only from TRUENAME, and only after
;;; paths have been converted to absolute paths, so we don't need to
;;; try to handle any more generality than that.
(defun unix-resolve-links (pathname)
(declare (type simple-string pathname))
(aver (not (relative-unix-pathname? pathname)))
(/noshow "entering UNIX-RESOLVE-LINKS")
(loop with previous-pathnames = nil do
(/noshow pathname previous-pathnames)
(let ((link (unix-readlink pathname)))
(/noshow link)
;; Unlike the old CMU CL code, we handle a broken symlink by
;; returning the link itself. That way, CL:TRUENAME on a
;; broken link returns the link itself, so that CL:DIRECTORY
;; can return broken links, so that even without
;; Unix-specific extensions to do interesting things with
;; them, at least Lisp programs can see them and, if
;; necessary, delete them. (This is handy e.g. when your
;; managed-by-Lisp directories are visited by Emacs, which
;; creates broken links as notes to itself.)
(if (null link)
(return pathname)
(let ((new-pathname
(unix-simplify-pathname
(if (relative-unix-pathname? link)
(let* ((dir-len (1+ (position #\/
pathname
:from-end t)))
(dir (subseq pathname 0 dir-len)))
(/noshow dir)
(concatenate 'string dir link))
link))))
(if (unix-file-kind new-pathname)
(setf pathname new-pathname)
(return pathname)))))
;; To generalize the principle that even if portable Lisp code
;; can't do anything interesting with a broken symlink, at
;; least it should be able to see and delete it, when we
;; detect a cyclic link, we return the link itself. (So even
;; though portable Lisp code can't do anything interesting
;; with a cyclic link, at least it can see it and delete it.)
(if (member pathname previous-pathnames :test #'string=)
(return pathname)
(push pathname previous-pathnames))))
(defun unix-simplify-pathname (src)
(declare (type simple-string src))
(let* ((src-len (length src))
(dst (make-string src-len))
(dst-len 0)
(dots 0)
(last-slash nil))
(macrolet ((deposit (char)
`(progn
(setf (schar dst dst-len) ,char)
(incf dst-len))))
(dotimes (src-index src-len)
(let ((char (schar src src-index)))
(cond ((char= char #\.)
(when dots
(incf dots))
(deposit char))
((char= char #\/)
(case dots
(0
;; either ``/...' or ``...//...'
(unless last-slash
(setf last-slash dst-len)
(deposit char)))
(1
;; either ``./...'' or ``..././...''
(decf dst-len))
(2
;; We've found ..
(cond
((and last-slash (not (zerop last-slash)))
;; There is something before this ..
(let ((prev-prev-slash
(position #\/ dst :end last-slash :from-end t)))
(cond ((and (= (+ (or prev-prev-slash 0) 2)
last-slash)
(char= (schar dst (- last-slash 2)) #\.)
(char= (schar dst (1- last-slash)) #\.))
;; The something before this .. is another ..
(deposit char)
(setf last-slash dst-len))
(t
;; The something is some directory or other.
(setf dst-len
(if prev-prev-slash
(1+ prev-prev-slash)
0))
(setf last-slash prev-prev-slash)))))
(t
;; There is nothing before this .., so we need to keep it
(setf last-slash dst-len)
(deposit char))))
(t
;; something other than a dot between slashes
(setf last-slash dst-len)
(deposit char)))
(setf dots 0))
(t
(setf dots nil)
(setf (schar dst dst-len) char)
(incf dst-len))))))
(when (and last-slash (not (zerop last-slash)))
(case dots
(1
;; We've got ``foobar/.''
(decf dst-len))
(2
;; We've got ``foobar/..''
(unless (and (>= last-slash 2)
(char= (schar dst (1- last-slash)) #\.)
(char= (schar dst (- last-slash 2)) #\.)
(or (= last-slash 2)
(char= (schar dst (- last-slash 3)) #\/)))
(let ((prev-prev-slash
(position #\/ dst :end last-slash :from-end t)))
(if prev-prev-slash
(setf dst-len (1+ prev-prev-slash))
(return-from unix-simplify-pathname "./")))))))
(cond ((zerop dst-len)
"./")
((= dst-len src-len)
dst)
(t
(subseq dst 0 dst-len)))))
;;;; A magic constant for wait3().
;;;;
;;;; FIXME: This used to be defined in run-program.lisp as
;;;; (defconstant wait-wstopped #-svr4 #o177 #+svr4 wait-wuntraced)
;;;; According to some of the man pages, the #o177 is part of the API
;;;; for wait3(); that said, under SunOS there is a WSTOPPED thing in
;;;; the headers that may or may not be the same thing. To be
;;;; investigated. -- CSR, 2002-03-25
(defconstant wstopped #o177)
;;;; stuff not yet found in the header files
;;;;
;;;; Abandon all hope who enters here...
;;; not checked for linux...
(defmacro fd-set (offset fd-set)
(let ((word (gensym))
(bit (gensym)))
`(multiple-value-bind (,word ,bit) (floor ,offset 32)
(setf (deref (slot ,fd-set 'fds-bits) ,word)
(logior (truly-the (unsigned-byte 32) (ash 1 ,bit))
(deref (slot ,fd-set 'fds-bits) ,word))))))
;;; not checked for linux...
(defmacro fd-clr (offset fd-set)
(let ((word (gensym))
(bit (gensym)))
`(multiple-value-bind (,word ,bit) (floor ,offset 32)
(setf (deref (slot ,fd-set 'fds-bits) ,word)
(logand (deref (slot ,fd-set 'fds-bits) ,word)
(sb!kernel:32bit-logical-not
(truly-the (unsigned-byte 32) (ash 1 ,bit))))))))
;;; not checked for linux...
(defmacro fd-isset (offset fd-set)
(let ((word (gensym))
(bit (gensym)))
`(multiple-value-bind (,word ,bit) (floor ,offset 32)
(logbitp ,bit (deref (slot ,fd-set 'fds-bits) ,word)))))
;;; not checked for linux...
(defmacro fd-zero (fd-set)
`(progn
,@(loop for index upfrom 0 below (/ fd-setsize 32)
collect `(setf (deref (slot ,fd-set 'fds-bits) ,index) 0))))