/
fd-stream.lisp
2424 lines (2306 loc) · 107 KB
/
fd-stream.lisp
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
;;;; streams for UNIX file descriptors
;;;; 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!IMPL")
;;;; buffer manipulation routines
;;; FIXME: Is it really good to maintain this pool separate from the
;;; GC and the C malloc logic?
(defvar *available-buffers* ()
#!+sb-doc
"List of available buffers. Each buffer is an sap pointing to
bytes-per-buffer of memory.")
#!+sb-thread
(defvar *available-buffers-mutex* (sb!thread:make-mutex
:name "lock for *AVAILABLE-BUFFERS*")
#!+sb-doc
"Mutex for access to *AVAILABLE-BUFFERS*.")
(defmacro with-available-buffers-lock ((&optional) &body body)
;; WITHOUT-INTERRUPTS because streams are low-level enough to be
;; async signal safe, and in particular a C-c that brings up the
;; debugger while holding the mutex would lose badly
`(without-interrupts
(sb!thread:with-mutex (*available-buffers-mutex*)
,@body)))
(defconstant bytes-per-buffer (* 4 1024)
#!+sb-doc
"Number of bytes per buffer.")
;;; Return the next available buffer, creating one if necessary.
#!-sb-fluid (declaim (inline next-available-buffer))
(defun next-available-buffer ()
(with-available-buffers-lock ()
(if *available-buffers*
(pop *available-buffers*)
(allocate-system-memory bytes-per-buffer))))
;;;; the FD-STREAM structure
(defstruct (fd-stream
(:constructor %make-fd-stream)
(:conc-name fd-stream-)
(:predicate fd-stream-p)
(:include ansi-stream
(misc #'fd-stream-misc-routine))
(:copier nil))
;; the name of this stream
(name nil)
;; the file this stream is for
(file nil)
;; the backup file namestring for the old file, for :IF-EXISTS
;; :RENAME or :RENAME-AND-DELETE.
(original nil :type (or simple-string null))
(delete-original nil) ; for :if-exists :rename-and-delete
;;; the number of bytes per element
(element-size 1 :type index)
;; the type of element being transfered
(element-type 'base-char)
;; the Unix file descriptor
(fd -1 :type fixnum)
;; controls when the output buffer is flushed
(buffering :full :type (member :full :line :none))
;; controls whether the input buffer must be cleared before output
;; (must be done for files, not for sockets, pipes and other data
;; sources where input and output aren't related). non-NIL means
;; don't clear input buffer.
(dual-channel-p nil)
;; character position if known -- this may run into bignums, but
;; we probably should flip it into null then for efficiency's sake...
(char-pos nil :type (or unsigned-byte null))
;; T if input is waiting on FD. :EOF if we hit EOF.
(listen nil :type (member nil t :eof))
;; the input buffer
(unread nil)
(ibuf-sap nil :type (or system-area-pointer null))
(ibuf-length nil :type (or index null))
(ibuf-head 0 :type index)
(ibuf-tail 0 :type index)
;; the output buffer
(obuf-sap nil :type (or system-area-pointer null))
(obuf-length nil :type (or index null))
(obuf-tail 0 :type index)
;; output flushed, but not written due to non-blocking io?
(output-later nil)
(handler nil)
;; timeout specified for this stream as seconds or NIL if none
(timeout nil :type (or single-float null))
;; pathname of the file this stream is opened to (returned by PATHNAME)
(pathname nil :type (or pathname null))
(external-format :default)
(output-bytes #'ill-out :type function))
(def!method print-object ((fd-stream fd-stream) stream)
(declare (type stream stream))
(print-unreadable-object (fd-stream stream :type t :identity t)
(format stream "for ~S" (fd-stream-name fd-stream))))
;;;; output routines and related noise
(defvar *output-routines* ()
#!+sb-doc
"List of all available output routines. Each element is a list of the
element-type output, the kind of buffering, the function name, and the number
of bytes per element.")
;;; common idioms for reporting low-level stream and file problems
(defun simple-stream-perror (note-format stream errno)
(error 'simple-stream-error
:stream stream
:format-control "~@<~?: ~2I~_~A~:>"
:format-arguments (list note-format (list stream) (strerror errno))))
(defun simple-file-perror (note-format pathname errno)
(error 'simple-file-error
:pathname pathname
:format-control "~@<~?: ~2I~_~A~:>"
:format-arguments
(list note-format (list pathname) (strerror errno))))
(defun stream-decoding-error (stream octets)
(error 'stream-decoding-error
:stream stream
;; FIXME: dunno how to get at OCTETS currently, or even if
;; that's the right thing to report.
:octets octets))
(defun stream-encoding-error (stream code)
(error 'stream-encoding-error
:stream stream
:code code))
(defun c-string-encoding-error (external-format code)
(error 'c-string-encoding-error
:external-format external-format
:code code))
(defun c-string-decoding-error (external-format octets)
(error 'c-string-decoding-error
:external-format external-format
:octets octets))
;;; Returning true goes into end of file handling, false will enter another
;;; round of input buffer filling followed by re-entering character decode.
(defun stream-decoding-error-and-handle (stream octet-count)
(restart-case
(stream-decoding-error stream
(let ((sap (fd-stream-ibuf-sap stream))
(head (fd-stream-ibuf-head stream)))
(loop for i from 0 below octet-count
collect (sap-ref-8 sap (+ head i)))))
(attempt-resync ()
:report (lambda (stream)
(format stream
"~@<Attempt to resync the stream at a character ~
character boundary and continue.~@:>"))
(fd-stream-resync stream)
nil)
(force-end-of-file ()
:report (lambda (stream)
(format stream "~@<Force an end of file.~@:>"))
t)))
(defun stream-encoding-error-and-handle (stream code)
(restart-case
(stream-encoding-error stream code)
(output-nothing ()
:report (lambda (stream)
(format stream "~@<Skip output of this character.~@:>"))
(throw 'output-nothing nil))))
(defun external-format-encoding-error (stream code)
(if (streamp stream)
(stream-encoding-error-and-handle stream code)
(c-string-encoding-error stream code)))
(defun external-format-decoding-error (stream octet-count)
(if (streamp stream)
(stream-decoding-error stream octet-count)
(c-string-decoding-error stream octet-count)))
;;; This is called by the server when we can write to the given file
;;; descriptor. Attempt to write the data again. If it worked, remove
;;; the data from the OUTPUT-LATER list. If it didn't work, something
;;; is wrong.
(defun frob-output-later (stream)
(let* ((stuff (pop (fd-stream-output-later stream)))
(base (car stuff))
(start (cadr stuff))
(end (caddr stuff))
(reuse-sap (cadddr stuff))
(length (- end start)))
(declare (type index start end length))
(multiple-value-bind (count errno)
(sb!unix:unix-write (fd-stream-fd stream)
base
start
length)
(cond ((not count)
#!+win32
(simple-stream-perror "couldn't write to ~S" stream errno)
#!-win32
(if (= errno sb!unix:ewouldblock)
(error "Write would have blocked, but SERVER told us to go.")
(simple-stream-perror "couldn't write to ~S" stream errno)))
((eql count length) ; Hot damn, it worked.
(when reuse-sap
(with-available-buffers-lock ()
(push base *available-buffers*))))
((not (null count)) ; sorta worked..
(push (list base
(the index (+ start count))
end)
(fd-stream-output-later stream))))))
(unless (fd-stream-output-later stream)
(remove-fd-handler (fd-stream-handler stream))
(setf (fd-stream-handler stream) nil)))
;;; Arange to output the string when we can write on the file descriptor.
(defun output-later (stream base start end reuse-sap)
(cond ((null (fd-stream-output-later stream))
(setf (fd-stream-output-later stream)
(list (list base start end reuse-sap)))
(setf (fd-stream-handler stream)
(add-fd-handler (fd-stream-fd stream)
:output
(lambda (fd)
(declare (ignore fd))
(frob-output-later stream)))))
(t
(nconc (fd-stream-output-later stream)
(list (list base start end reuse-sap)))))
(when reuse-sap
(let ((new-buffer (next-available-buffer)))
(setf (fd-stream-obuf-sap stream) new-buffer)
(setf (fd-stream-obuf-length stream) bytes-per-buffer))))
;;; Output the given noise. Check to see whether there are any pending
;;; writes. If so, just queue this one. Otherwise, try to write it. If
;;; this would block, queue it.
(defun frob-output (stream base start end reuse-sap)
(declare (type fd-stream stream)
(type (or system-area-pointer (simple-array * (*))) base)
(type index start end))
(if (not (null (fd-stream-output-later stream))) ; something buffered.
(output-later stream base start end reuse-sap)
;; ### check to see whether any of this noise can be output
(let ((length (- end start)))
(multiple-value-bind (count errno)
(sb!unix:unix-write (fd-stream-fd stream) base start length)
(cond ((not count)
#!+win32
(simple-stream-perror "Couldn't write to ~S" stream errno)
#!-win32
(if (= errno sb!unix:ewouldblock)
(output-later stream base start end reuse-sap)
(simple-stream-perror "Couldn't write to ~S"
stream errno)))
((not (eql count length))
(output-later stream base (the index (+ start count))
end reuse-sap)))))))
;;; Flush any data in the output buffer.
(defun flush-output-buffer (stream)
(let ((length (fd-stream-obuf-tail stream)))
(unless (= length 0)
(frob-output stream (fd-stream-obuf-sap stream) 0 length t)
(setf (fd-stream-obuf-tail stream) 0))))
(defun fd-stream-output-finished-p (stream)
(and (zerop (fd-stream-obuf-tail stream))
(not (fd-stream-output-later stream))))
(defmacro output-wrapper/variable-width ((stream size buffering restart)
&body body)
(let ((stream-var (gensym)))
`(let ((,stream-var ,stream)
(size ,size))
,(unless (eq (car buffering) :none)
`(when (< (fd-stream-obuf-length ,stream-var)
(+ (fd-stream-obuf-tail ,stream-var)
size))
(flush-output-buffer ,stream-var)))
,(unless (eq (car buffering) :none)
`(when (and (not (fd-stream-dual-channel-p ,stream-var))
(> (fd-stream-ibuf-tail ,stream-var)
(fd-stream-ibuf-head ,stream-var)))
(file-position ,stream-var (file-position ,stream-var))))
,(if restart
`(catch 'output-nothing
,@body
(incf (fd-stream-obuf-tail ,stream-var) size))
`(progn
,@body
(incf (fd-stream-obuf-tail ,stream-var) size)))
,(ecase (car buffering)
(:none
`(flush-output-buffer ,stream-var))
(:line
`(when (eq (char-code byte) (char-code #\Newline))
(flush-output-buffer ,stream-var)))
(:full))
(values))))
(defmacro output-wrapper ((stream size buffering restart) &body body)
(let ((stream-var (gensym)))
`(let ((,stream-var ,stream))
,(unless (eq (car buffering) :none)
`(when (< (fd-stream-obuf-length ,stream-var)
(+ (fd-stream-obuf-tail ,stream-var)
,size))
(flush-output-buffer ,stream-var)))
,(unless (eq (car buffering) :none)
`(when (and (not (fd-stream-dual-channel-p ,stream-var))
(> (fd-stream-ibuf-tail ,stream-var)
(fd-stream-ibuf-head ,stream-var)))
(file-position ,stream-var (file-position ,stream-var))))
,(if restart
`(catch 'output-nothing
,@body
(incf (fd-stream-obuf-tail ,stream-var) ,size))
`(progn
,@body
(incf (fd-stream-obuf-tail ,stream-var) ,size)))
,(ecase (car buffering)
(:none
`(flush-output-buffer ,stream-var))
(:line
`(when (eq (char-code byte) (char-code #\Newline))
(flush-output-buffer ,stream-var)))
(:full))
(values))))
(defmacro def-output-routines/variable-width
((name-fmt size restart external-format &rest bufferings)
&body body)
(declare (optimize (speed 1)))
(cons 'progn
(mapcar
(lambda (buffering)
(let ((function
(intern (format nil name-fmt (string (car buffering))))))
`(progn
(defun ,function (stream byte)
(declare (ignorable byte))
(output-wrapper/variable-width (stream ,size ,buffering ,restart)
,@body))
(setf *output-routines*
(nconc *output-routines*
',(mapcar
(lambda (type)
(list type
(car buffering)
function
1
external-format))
(cdr buffering)))))))
bufferings)))
;;; Define output routines that output numbers SIZE bytes long for the
;;; given bufferings. Use BODY to do the actual output.
(defmacro def-output-routines ((name-fmt size restart &rest bufferings)
&body body)
(declare (optimize (speed 1)))
(cons 'progn
(mapcar
(lambda (buffering)
(let ((function
(intern (format nil name-fmt (string (car buffering))))))
`(progn
(defun ,function (stream byte)
(output-wrapper (stream ,size ,buffering ,restart)
,@body))
(setf *output-routines*
(nconc *output-routines*
',(mapcar
(lambda (type)
(list type
(car buffering)
function
size
nil))
(cdr buffering)))))))
bufferings)))
;;; FIXME: is this used anywhere any more?
(def-output-routines ("OUTPUT-CHAR-~A-BUFFERED"
1
t
(:none character)
(:line character)
(:full character))
(if (char= byte #\Newline)
(setf (fd-stream-char-pos stream) 0)
(incf (fd-stream-char-pos stream)))
(setf (sap-ref-8 (fd-stream-obuf-sap stream) (fd-stream-obuf-tail stream))
(char-code byte)))
(def-output-routines ("OUTPUT-UNSIGNED-BYTE-~A-BUFFERED"
1
nil
(:none (unsigned-byte 8))
(:full (unsigned-byte 8)))
(setf (sap-ref-8 (fd-stream-obuf-sap stream) (fd-stream-obuf-tail stream))
byte))
(def-output-routines ("OUTPUT-SIGNED-BYTE-~A-BUFFERED"
1
nil
(:none (signed-byte 8))
(:full (signed-byte 8)))
(setf (signed-sap-ref-8 (fd-stream-obuf-sap stream)
(fd-stream-obuf-tail stream))
byte))
(def-output-routines ("OUTPUT-UNSIGNED-SHORT-~A-BUFFERED"
2
nil
(:none (unsigned-byte 16))
(:full (unsigned-byte 16)))
(setf (sap-ref-16 (fd-stream-obuf-sap stream) (fd-stream-obuf-tail stream))
byte))
(def-output-routines ("OUTPUT-SIGNED-SHORT-~A-BUFFERED"
2
nil
(:none (signed-byte 16))
(:full (signed-byte 16)))
(setf (signed-sap-ref-16 (fd-stream-obuf-sap stream)
(fd-stream-obuf-tail stream))
byte))
(def-output-routines ("OUTPUT-UNSIGNED-LONG-~A-BUFFERED"
4
nil
(:none (unsigned-byte 32))
(:full (unsigned-byte 32)))
(setf (sap-ref-32 (fd-stream-obuf-sap stream) (fd-stream-obuf-tail stream))
byte))
(def-output-routines ("OUTPUT-SIGNED-LONG-~A-BUFFERED"
4
nil
(:none (signed-byte 32))
(:full (signed-byte 32)))
(setf (signed-sap-ref-32 (fd-stream-obuf-sap stream)
(fd-stream-obuf-tail stream))
byte))
#+#.(cl:if (cl:= sb!vm:n-word-bits 64) '(and) '(or))
(progn
(def-output-routines ("OUTPUT-UNSIGNED-LONG-LONG-~A-BUFFERED"
8
nil
(:none (unsigned-byte 64))
(:full (unsigned-byte 64)))
(setf (sap-ref-64 (fd-stream-obuf-sap stream) (fd-stream-obuf-tail stream))
byte))
(def-output-routines ("OUTPUT-SIGNED-LONG-LONG-~A-BUFFERED"
8
nil
(:none (signed-byte 64))
(:full (signed-byte 64)))
(setf (signed-sap-ref-64 (fd-stream-obuf-sap stream)
(fd-stream-obuf-tail stream))
byte)))
;;; Do the actual output. If there is space to buffer the string,
;;; buffer it. If the string would normally fit in the buffer, but
;;; doesn't because of other stuff in the buffer, flush the old noise
;;; out of the buffer and put the string in it. Otherwise we have a
;;; very long string, so just send it directly (after flushing the
;;; buffer, of course).
(defun output-raw-bytes (fd-stream thing &optional start end)
#!+sb-doc
"Output THING to FD-STREAM. THING can be any kind of vector or a SAP. If
THING is a SAP, END must be supplied (as length won't work)."
(let ((start (or start 0))
(end (or end (length (the (simple-array * (*)) thing)))))
(declare (type index start end))
(when (and (not (fd-stream-dual-channel-p fd-stream))
(> (fd-stream-ibuf-tail fd-stream)
(fd-stream-ibuf-head fd-stream)))
(file-position fd-stream (file-position fd-stream)))
(let* ((len (fd-stream-obuf-length fd-stream))
(tail (fd-stream-obuf-tail fd-stream))
(space (- len tail))
(bytes (- end start))
(newtail (+ tail bytes)))
(cond ((minusp bytes) ; error case
(error ":END before :START!"))
((zerop bytes)) ; easy case
((<= bytes space)
(if (system-area-pointer-p thing)
(system-area-ub8-copy thing start
(fd-stream-obuf-sap fd-stream)
tail
bytes)
;; FIXME: There should be some type checking somewhere to
;; verify that THING here is a vector, not just <not a SAP>.
(copy-ub8-to-system-area thing start
(fd-stream-obuf-sap fd-stream)
tail
bytes))
(setf (fd-stream-obuf-tail fd-stream) newtail))
((<= bytes len)
(flush-output-buffer fd-stream)
(if (system-area-pointer-p thing)
(system-area-ub8-copy thing
start
(fd-stream-obuf-sap fd-stream)
0
bytes)
;; FIXME: There should be some type checking somewhere to
;; verify that THING here is a vector, not just <not a SAP>.
(copy-ub8-to-system-area thing
start
(fd-stream-obuf-sap fd-stream)
0
bytes))
(setf (fd-stream-obuf-tail fd-stream) bytes))
(t
(flush-output-buffer fd-stream)
(frob-output fd-stream thing start end nil))))))
;;; the routine to use to output a string. If the stream is
;;; unbuffered, slam the string down the file descriptor, otherwise
;;; use OUTPUT-RAW-BYTES to buffer the string. Update charpos by
;;; checking to see where the last newline was.
(defun fd-sout (stream thing start end)
(declare (type fd-stream stream) (type string thing))
(let ((start (or start 0))
(end (or end (length (the vector thing)))))
(declare (fixnum start end))
(let ((last-newline
(string-dispatch (simple-base-string
#!+sb-unicode
(simple-array character (*))
string)
thing
(position #\newline thing :from-end t
:start start :end end))))
(if (and (typep thing 'base-string)
(eq (fd-stream-external-format stream) :latin-1))
(ecase (fd-stream-buffering stream)
(:full
(output-raw-bytes stream thing start end))
(:line
(output-raw-bytes stream thing start end)
(when last-newline
(flush-output-buffer stream)))
(:none
(frob-output stream thing start end nil)))
(ecase (fd-stream-buffering stream)
(:full (funcall (fd-stream-output-bytes stream)
stream thing nil start end))
(:line (funcall (fd-stream-output-bytes stream)
stream thing last-newline start end))
(:none (funcall (fd-stream-output-bytes stream)
stream thing t start end))))
(if last-newline
(setf (fd-stream-char-pos stream) (- end last-newline 1))
(incf (fd-stream-char-pos stream) (- end start))))))
(defvar *external-formats* ()
#!+sb-doc
"List of all available external formats. Each element is a list of the
element-type, string input function name, character input function name,
and string output function name.")
(defun get-external-format (external-format)
(dolist (entry *external-formats*)
(when (member external-format (first entry))
(return entry))))
(defun get-external-format-function (external-format index)
(let ((entry (get-external-format external-format)))
(when entry (nth index entry))))
;;; Find an output routine to use given the type and buffering. Return
;;; as multiple values the routine, the real type transfered, and the
;;; number of bytes per element.
(defun pick-output-routine (type buffering &optional external-format)
(when (subtypep type 'character)
(let ((entry (get-external-format external-format)))
(when entry
(return-from pick-output-routine
(values (symbol-function (nth (ecase buffering
(:none 4)
(:line 5)
(:full 6))
entry))
'character
1
(symbol-function (fourth entry))
(first (first entry)))))))
(dolist (entry *output-routines*)
(when (and (subtypep type (first entry))
(eq buffering (second entry))
(or (not (fifth entry))
(eq external-format (fifth entry))))
(return-from pick-output-routine
(values (symbol-function (third entry))
(first entry)
(fourth entry)))))
;; KLUDGE: dealing with the buffering here leads to excessive code
;; explosion.
;;
;; KLUDGE: also see comments in PICK-INPUT-ROUTINE
(loop for i from 40 by 8 to 1024 ; ARB (KLUDGE)
if (subtypep type `(unsigned-byte ,i))
do (return-from pick-output-routine
(values
(ecase buffering
(:none
(lambda (stream byte)
(output-wrapper (stream (/ i 8) (:none) nil)
(loop for j from 0 below (/ i 8)
do (setf (sap-ref-8
(fd-stream-obuf-sap stream)
(+ j (fd-stream-obuf-tail stream)))
(ldb (byte 8 (- i 8 (* j 8))) byte))))))
(:full
(lambda (stream byte)
(output-wrapper (stream (/ i 8) (:full) nil)
(loop for j from 0 below (/ i 8)
do (setf (sap-ref-8
(fd-stream-obuf-sap stream)
(+ j (fd-stream-obuf-tail stream)))
(ldb (byte 8 (- i 8 (* j 8))) byte)))))))
`(unsigned-byte ,i)
(/ i 8))))
(loop for i from 40 by 8 to 1024 ; ARB (KLUDGE)
if (subtypep type `(signed-byte ,i))
do (return-from pick-output-routine
(values
(ecase buffering
(:none
(lambda (stream byte)
(output-wrapper (stream (/ i 8) (:none) nil)
(loop for j from 0 below (/ i 8)
do (setf (sap-ref-8
(fd-stream-obuf-sap stream)
(+ j (fd-stream-obuf-tail stream)))
(ldb (byte 8 (- i 8 (* j 8))) byte))))))
(:full
(lambda (stream byte)
(output-wrapper (stream (/ i 8) (:full) nil)
(loop for j from 0 below (/ i 8)
do (setf (sap-ref-8
(fd-stream-obuf-sap stream)
(+ j (fd-stream-obuf-tail stream)))
(ldb (byte 8 (- i 8 (* j 8))) byte)))))))
`(signed-byte ,i)
(/ i 8)))))
;;;; input routines and related noise
;;; a list of all available input routines. Each element is a list of
;;; the element-type input, the function name, and the number of bytes
;;; per element.
(defvar *input-routines* ())
;;; Return whether a primitive partial read operation on STREAM's FD
;;; would (probably) block. Signal a `simple-stream-error' if the
;;; system call implementing this operation fails.
;;;
;;; It is "may" instead of "would" because "would" is not quite
;;; correct on win32. However, none of the places that use it require
;;; further assurance than "may" versus "will definitely not".
(defun sysread-may-block-p (stream)
#+win32
;; This answers T at EOF on win32, I think.
(not (sb!win32:fd-listen (fd-stream-fd stream)))
#-win32
(sb!unix:with-restarted-syscall (count errno)
(sb!alien:with-alien ((read-fds (sb!alien:struct sb!unix:fd-set)))
(sb!unix:fd-zero read-fds)
(sb!unix:fd-set (fd-stream-fd stream) read-fds)
(sb!unix:unix-fast-select (1+ (fd-stream-fd stream))
(sb!alien:addr read-fds)
nil nil 0 0))
(case count
((1) nil)
((0) t)
(otherwise
(simple-stream-perror "couldn't check whether ~S is readable"
stream
errno)))))
;;; If the read would block wait (using SERVE-EVENT) till input is available,
;;; then fill the input buffer, and return the number of bytes read. Throws
;;; to EOF-INPUT-CATCHER if the eof was reached.
(defun refill-buffer/fd (stream)
(let ((fd (fd-stream-fd stream))
(errno 0)
(count 0))
(tagbody
;; Check for blocking input before touching the stream, as if
;; we happen to wait we are liable to be interrupted, and the
;; interrupt handler may use the same stream.
(if (sysread-may-block-p stream)
(go :wait-for-input)
(go :main))
;; These (:CLOSED-FLAME and :READ-ERROR) tags are here so what
;; we can signal errors outside the WITHOUT-INTERRUPTS.
:closed-flame
(closed-flame stream)
:read-error
(simple-stream-perror "couldn't read from ~S" stream errno)
:wait-for-input
;; This tag is here so we can unwind outside the WITHOUT-INTERRUPTS
;; to wait for input if read tells us EWOULDBLOCK.
(unless (wait-until-fd-usable fd :input (fd-stream-timeout stream))
(signal-timeout 'io-timeout :stream stream :direction :read
:seconds (fd-stream-timeout stream)))
:main
;; Since the read should not block, we'll disable the
;; interrupts here, so that we don't accidentally unwind and
;; leave the stream in an inconsistent state.
(without-interrupts
(let ((ibuf-sap (fd-stream-ibuf-sap stream))
(buflen (fd-stream-ibuf-length stream))
(head (fd-stream-ibuf-head stream))
(tail (fd-stream-ibuf-tail stream)))
(declare (type index head tail))
;; Check the SAP: if it is null, then someone has closed
;; the stream from underneath us. This is not ment to fix
;; multithreaded races, but to deal with interrupt handlers
;; closing the stream.
(unless ibuf-sap
(go :closed-flame))
(unless (zerop head)
(cond ((eql head tail)
(setf head 0
tail 0
(fd-stream-ibuf-head stream) 0
(fd-stream-ibuf-tail stream) 0))
(t
(decf tail head)
(system-area-ub8-copy ibuf-sap head
ibuf-sap 0 tail)
(setf head 0
(fd-stream-ibuf-head stream) 0
(fd-stream-ibuf-tail stream) tail))))
(setf (fd-stream-listen stream) nil)
(setf (values count errno)
(sb!unix:unix-read fd (int-sap (+ (sap-int ibuf-sap) tail))
(- buflen tail)))
(cond ((null count)
#!+win32
(go :read-error)
#!-win32
(if (eql errno sb!unix:ewouldblock)
(go :wait-for-input)
(go :read-error)))
((zerop count)
(setf (fd-stream-listen stream) :eof)
(/show0 "THROWing EOF-INPUT-CATCHER")
(throw 'eof-input-catcher nil))
(t
;; Success!
(incf (fd-stream-ibuf-tail stream) count))))))
count))
;;; Make sure there are at least BYTES number of bytes in the input
;;; buffer. Keep calling REFILL-BUFFER/FD until that condition is met.
(defmacro input-at-least (stream bytes)
(let ((stream-var (gensym))
(bytes-var (gensym)))
`(let ((,stream-var ,stream)
(,bytes-var ,bytes))
(loop
(when (>= (- (fd-stream-ibuf-tail ,stream-var)
(fd-stream-ibuf-head ,stream-var))
,bytes-var)
(return))
(refill-buffer/fd ,stream-var)))))
(defmacro input-wrapper/variable-width ((stream bytes eof-error eof-value)
&body read-forms)
(let ((stream-var (gensym))
(retry-var (gensym))
(element-var (gensym)))
`(let ((,stream-var ,stream)
(size nil))
(if (fd-stream-unread ,stream-var)
(prog1
(fd-stream-unread ,stream-var)
(setf (fd-stream-unread ,stream-var) nil)
(setf (fd-stream-listen ,stream-var) nil))
(let ((,element-var nil)
(decode-break-reason nil))
(do ((,retry-var t))
((not ,retry-var))
(unless
(catch 'eof-input-catcher
(setf decode-break-reason
(block decode-break-reason
(input-at-least ,stream-var 1)
(let* ((byte (sap-ref-8 (fd-stream-ibuf-sap
,stream-var)
(fd-stream-ibuf-head
,stream-var))))
(declare (ignorable byte))
(setq size ,bytes)
(input-at-least ,stream-var size)
(setq ,element-var (locally ,@read-forms))
(setq ,retry-var nil))
nil))
(when decode-break-reason
(stream-decoding-error-and-handle stream
decode-break-reason))
t)
(let ((octet-count (- (fd-stream-ibuf-tail ,stream-var)
(fd-stream-ibuf-head ,stream-var))))
(when (or (zerop octet-count)
(and (not ,element-var)
(not decode-break-reason)
(stream-decoding-error-and-handle
stream octet-count)))
(setq ,retry-var nil)))))
(cond (,element-var
(incf (fd-stream-ibuf-head ,stream-var) size)
,element-var)
(t
(eof-or-lose ,stream-var ,eof-error ,eof-value))))))))
;;; a macro to wrap around all input routines to handle EOF-ERROR noise
(defmacro input-wrapper ((stream bytes eof-error eof-value) &body read-forms)
(let ((stream-var (gensym))
(element-var (gensym)))
`(let ((,stream-var ,stream))
(if (fd-stream-unread ,stream-var)
(prog1
(fd-stream-unread ,stream-var)
(setf (fd-stream-unread ,stream-var) nil)
(setf (fd-stream-listen ,stream-var) nil))
(let ((,element-var
(catch 'eof-input-catcher
(input-at-least ,stream-var ,bytes)
(locally ,@read-forms))))
(cond (,element-var
(incf (fd-stream-ibuf-head ,stream-var) ,bytes)
,element-var)
(t
(eof-or-lose ,stream-var ,eof-error ,eof-value))))))))
(defmacro def-input-routine/variable-width (name
(type external-format size sap head)
&rest body)
`(progn
(defun ,name (stream eof-error eof-value)
(input-wrapper/variable-width (stream ,size eof-error eof-value)
(let ((,sap (fd-stream-ibuf-sap stream))
(,head (fd-stream-ibuf-head stream)))
,@body)))
(setf *input-routines*
(nconc *input-routines*
(list (list ',type ',name 1 ',external-format))))))
(defmacro def-input-routine (name
(type size sap head)
&rest body)
`(progn
(defun ,name (stream eof-error eof-value)
(input-wrapper (stream ,size eof-error eof-value)
(let ((,sap (fd-stream-ibuf-sap stream))
(,head (fd-stream-ibuf-head stream)))
,@body)))
(setf *input-routines*
(nconc *input-routines*
(list (list ',type ',name ',size nil))))))
;;; STREAM-IN routine for reading a string char
(def-input-routine input-character
(character 1 sap head)
(code-char (sap-ref-8 sap head)))
;;; STREAM-IN routine for reading an unsigned 8 bit number
(def-input-routine input-unsigned-8bit-byte
((unsigned-byte 8) 1 sap head)
(sap-ref-8 sap head))
;;; STREAM-IN routine for reading a signed 8 bit number
(def-input-routine input-signed-8bit-number
((signed-byte 8) 1 sap head)
(signed-sap-ref-8 sap head))
;;; STREAM-IN routine for reading an unsigned 16 bit number
(def-input-routine input-unsigned-16bit-byte
((unsigned-byte 16) 2 sap head)
(sap-ref-16 sap head))
;;; STREAM-IN routine for reading a signed 16 bit number
(def-input-routine input-signed-16bit-byte
((signed-byte 16) 2 sap head)
(signed-sap-ref-16 sap head))
;;; STREAM-IN routine for reading a unsigned 32 bit number
(def-input-routine input-unsigned-32bit-byte
((unsigned-byte 32) 4 sap head)
(sap-ref-32 sap head))
;;; STREAM-IN routine for reading a signed 32 bit number
(def-input-routine input-signed-32bit-byte
((signed-byte 32) 4 sap head)
(signed-sap-ref-32 sap head))
#+#.(cl:if (cl:= sb!vm:n-word-bits 64) '(and) '(or))
(progn
(def-input-routine input-unsigned-64bit-byte
((unsigned-byte 64) 8 sap head)
(sap-ref-64 sap head))
(def-input-routine input-signed-64bit-byte
((signed-byte 64) 8 sap head)
(signed-sap-ref-64 sap head)))
;;; Find an input routine to use given the type. Return as multiple
;;; values the routine, the real type transfered, and the number of
;;; bytes per element (and for character types string input routine).
(defun pick-input-routine (type &optional external-format)
(when (subtypep type 'character)
(dolist (entry *external-formats*)
(when (member external-format (first entry))
(return-from pick-input-routine
(values (symbol-function (third entry))
'character
1
(symbol-function (second entry))
(first (first entry)))))))
(dolist (entry *input-routines*)
(when (and (subtypep type (first entry))
(or (not (fourth entry))
(eq external-format (fourth entry))))
(return-from pick-input-routine
(values (symbol-function (second entry))
(first entry)
(third entry)))))
;; FIXME: let's do it the hard way, then (but ignore things like
;; endianness, efficiency, and the necessary coupling between these
;; and the output routines). -- CSR, 2004-02-09
(loop for i from 40 by 8 to 1024 ; ARB (well, KLUDGE really)
if (subtypep type `(unsigned-byte ,i))
do (return-from pick-input-routine
(values
(lambda (stream eof-error eof-value)
(input-wrapper (stream (/ i 8) eof-error eof-value)
(let ((sap (fd-stream-ibuf-sap stream))
(head (fd-stream-ibuf-head stream)))
(loop for j from 0 below (/ i 8)
with result = 0
do (setf result
(+ (* 256 result)
(sap-ref-8 sap (+ head j))))
finally (return result)))))
`(unsigned-byte ,i)
(/ i 8))))
(loop for i from 40 by 8 to 1024 ; ARB (well, KLUDGE really)
if (subtypep type `(signed-byte ,i))
do (return-from pick-input-routine
(values
(lambda (stream eof-error eof-value)
(input-wrapper (stream (/ i 8) eof-error eof-value)
(let ((sap (fd-stream-ibuf-sap stream))
(head (fd-stream-ibuf-head stream)))
(loop for j from 0 below (/ i 8)
with result = 0
do (setf result
(+ (* 256 result)
(sap-ref-8 sap (+ head j))))
finally (return (if (logbitp (1- i) result)
(dpb result (byte i 0) -1)
result))))))
`(signed-byte ,i)
(/ i 8)))))
;;; Return a string constructed from SAP, START, and END.
(defun string-from-sap (sap start end)
(declare (type index start end))
(let* ((length (- end start))
(string (make-string length)))
(copy-ub8-from-system-area sap start
string 0
length)
string))
;;; the N-BIN method for FD-STREAMs
;;;