-
-
Notifications
You must be signed in to change notification settings - Fork 30k
/
zlibmodule.c
1480 lines (1261 loc) · 40.9 KB
/
zlibmodule.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
/* zlibmodule.c -- gzip-compatible data compression */
/* See http://zlib.net/ */
/* Windows users: read Python's PCbuild\readme.txt */
#define PY_SSIZE_T_CLEAN
#include "Python.h"
#include "structmember.h" // PyMemberDef
#include "zlib.h"
#define ENTER_ZLIB(obj) \
Py_BEGIN_ALLOW_THREADS; \
PyThread_acquire_lock((obj)->lock, 1); \
Py_END_ALLOW_THREADS;
#define LEAVE_ZLIB(obj) PyThread_release_lock((obj)->lock);
#if defined(ZLIB_VERNUM) && ZLIB_VERNUM >= 0x1221
# define AT_LEAST_ZLIB_1_2_2_1
#endif
/* The following parameters are copied from zutil.h, version 0.95 */
#define DEFLATED 8
#if MAX_MEM_LEVEL >= 8
# define DEF_MEM_LEVEL 8
#else
# define DEF_MEM_LEVEL MAX_MEM_LEVEL
#endif
/* Initial buffer size. */
#define DEF_BUF_SIZE (16*1024)
static PyModuleDef zlibmodule;
typedef struct {
PyTypeObject *Comptype;
PyTypeObject *Decomptype;
PyObject *ZlibError;
} _zlibstate;
static inline _zlibstate*
get_zlib_state(PyObject *module)
{
void *state = PyModule_GetState(module);
assert(state != NULL);
return (_zlibstate *)state;
}
#define _zlibstate_global ((_zlibstate *)PyModule_GetState(PyState_FindModule(&zlibmodule)))
typedef struct
{
PyObject_HEAD
z_stream zst;
PyObject *unused_data;
PyObject *unconsumed_tail;
char eof;
int is_initialised;
PyObject *zdict;
PyThread_type_lock lock;
} compobject;
static void
zlib_error(z_stream zst, int err, const char *msg)
{
const char *zmsg = Z_NULL;
/* In case of a version mismatch, zst.msg won't be initialized.
Check for this case first, before looking at zst.msg. */
if (err == Z_VERSION_ERROR)
zmsg = "library version mismatch";
if (zmsg == Z_NULL)
zmsg = zst.msg;
if (zmsg == Z_NULL) {
switch (err) {
case Z_BUF_ERROR:
zmsg = "incomplete or truncated stream";
break;
case Z_STREAM_ERROR:
zmsg = "inconsistent stream state";
break;
case Z_DATA_ERROR:
zmsg = "invalid input data";
break;
}
}
if (zmsg == Z_NULL)
PyErr_Format(_zlibstate_global->ZlibError, "Error %d %s", err, msg);
else
PyErr_Format(_zlibstate_global->ZlibError, "Error %d %s: %.200s", err, msg, zmsg);
}
/*[clinic input]
module zlib
class zlib.Compress "compobject *" "&Comptype"
class zlib.Decompress "compobject *" "&Decomptype"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=093935115c3e3158]*/
static compobject *
newcompobject(PyTypeObject *type)
{
compobject *self;
self = PyObject_New(compobject, type);
if (self == NULL)
return NULL;
self->eof = 0;
self->is_initialised = 0;
self->zdict = NULL;
self->unused_data = PyBytes_FromStringAndSize("", 0);
if (self->unused_data == NULL) {
Py_DECREF(self);
return NULL;
}
self->unconsumed_tail = PyBytes_FromStringAndSize("", 0);
if (self->unconsumed_tail == NULL) {
Py_DECREF(self);
return NULL;
}
self->lock = PyThread_allocate_lock();
if (self->lock == NULL) {
Py_DECREF(self);
PyErr_SetString(PyExc_MemoryError, "Unable to allocate lock");
return NULL;
}
return self;
}
static void*
PyZlib_Malloc(voidpf ctx, uInt items, uInt size)
{
if (size != 0 && items > (size_t)PY_SSIZE_T_MAX / size)
return NULL;
/* PyMem_Malloc() cannot be used: the GIL is not held when
inflate() and deflate() are called */
return PyMem_RawMalloc((size_t)items * (size_t)size);
}
static void
PyZlib_Free(voidpf ctx, void *ptr)
{
PyMem_RawFree(ptr);
}
static void
arrange_input_buffer(z_stream *zst, Py_ssize_t *remains)
{
zst->avail_in = (uInt)Py_MIN((size_t)*remains, UINT_MAX);
*remains -= zst->avail_in;
}
static Py_ssize_t
arrange_output_buffer_with_maximum(z_stream *zst, PyObject **buffer,
Py_ssize_t length,
Py_ssize_t max_length)
{
Py_ssize_t occupied;
if (*buffer == NULL) {
if (!(*buffer = PyBytes_FromStringAndSize(NULL, length)))
return -1;
occupied = 0;
}
else {
occupied = zst->next_out - (Byte *)PyBytes_AS_STRING(*buffer);
if (length == occupied) {
Py_ssize_t new_length;
assert(length <= max_length);
/* can not scale the buffer over max_length */
if (length == max_length)
return -2;
if (length <= (max_length >> 1))
new_length = length << 1;
else
new_length = max_length;
if (_PyBytes_Resize(buffer, new_length) < 0)
return -1;
length = new_length;
}
}
zst->avail_out = (uInt)Py_MIN((size_t)(length - occupied), UINT_MAX);
zst->next_out = (Byte *)PyBytes_AS_STRING(*buffer) + occupied;
return length;
}
static Py_ssize_t
arrange_output_buffer(z_stream *zst, PyObject **buffer, Py_ssize_t length)
{
Py_ssize_t ret;
ret = arrange_output_buffer_with_maximum(zst, buffer, length,
PY_SSIZE_T_MAX);
if (ret == -2)
PyErr_NoMemory();
return ret;
}
/*[clinic input]
zlib.compress
data: Py_buffer
Binary data to be compressed.
/
level: int(c_default="Z_DEFAULT_COMPRESSION") = Z_DEFAULT_COMPRESSION
Compression level, in 0-9 or -1.
Returns a bytes object containing compressed data.
[clinic start generated code]*/
static PyObject *
zlib_compress_impl(PyObject *module, Py_buffer *data, int level)
/*[clinic end generated code: output=d80906d73f6294c8 input=638d54b6315dbed3]*/
{
PyObject *RetVal = NULL;
Byte *ibuf;
Py_ssize_t ibuflen, obuflen = DEF_BUF_SIZE;
int err, flush;
z_stream zst;
ibuf = data->buf;
ibuflen = data->len;
zst.opaque = NULL;
zst.zalloc = PyZlib_Malloc;
zst.zfree = PyZlib_Free;
zst.next_in = ibuf;
err = deflateInit(&zst, level);
switch (err) {
case Z_OK:
break;
case Z_MEM_ERROR:
PyErr_SetString(PyExc_MemoryError,
"Out of memory while compressing data");
goto error;
case Z_STREAM_ERROR:
PyErr_SetString(_zlibstate_global->ZlibError, "Bad compression level");
goto error;
default:
deflateEnd(&zst);
zlib_error(zst, err, "while compressing data");
goto error;
}
do {
arrange_input_buffer(&zst, &ibuflen);
flush = ibuflen == 0 ? Z_FINISH : Z_NO_FLUSH;
do {
obuflen = arrange_output_buffer(&zst, &RetVal, obuflen);
if (obuflen < 0) {
deflateEnd(&zst);
goto error;
}
Py_BEGIN_ALLOW_THREADS
err = deflate(&zst, flush);
Py_END_ALLOW_THREADS
if (err == Z_STREAM_ERROR) {
deflateEnd(&zst);
zlib_error(zst, err, "while compressing data");
goto error;
}
} while (zst.avail_out == 0);
assert(zst.avail_in == 0);
} while (flush != Z_FINISH);
assert(err == Z_STREAM_END);
err = deflateEnd(&zst);
if (err == Z_OK) {
if (_PyBytes_Resize(&RetVal, zst.next_out -
(Byte *)PyBytes_AS_STRING(RetVal)) < 0)
goto error;
return RetVal;
}
else
zlib_error(zst, err, "while finishing compression");
error:
Py_XDECREF(RetVal);
return NULL;
}
/*[python input]
class ssize_t_converter(CConverter):
type = 'Py_ssize_t'
converter = 'ssize_t_converter'
c_ignored_default = "0"
[python start generated code]*/
/*[python end generated code: output=da39a3ee5e6b4b0d input=5f34ba1b394cb8e7]*/
static int
ssize_t_converter(PyObject *obj, void *ptr)
{
PyObject *long_obj;
Py_ssize_t val;
/* XXX Should be replaced with PyNumber_AsSsize_t after the end of the
deprecation period. */
long_obj = _PyLong_FromNbIndexOrNbInt(obj);
if (long_obj == NULL) {
return 0;
}
val = PyLong_AsSsize_t(long_obj);
Py_DECREF(long_obj);
if (val == -1 && PyErr_Occurred()) {
return 0;
}
*(Py_ssize_t *)ptr = val;
return 1;
}
/*[clinic input]
zlib.decompress
data: Py_buffer
Compressed data.
/
wbits: int(c_default="MAX_WBITS") = MAX_WBITS
The window buffer size and container format.
bufsize: ssize_t(c_default="DEF_BUF_SIZE") = DEF_BUF_SIZE
The initial output buffer size.
Returns a bytes object containing the uncompressed data.
[clinic start generated code]*/
static PyObject *
zlib_decompress_impl(PyObject *module, Py_buffer *data, int wbits,
Py_ssize_t bufsize)
/*[clinic end generated code: output=77c7e35111dc8c42 input=21960936208e9a5b]*/
{
PyObject *RetVal = NULL;
Byte *ibuf;
Py_ssize_t ibuflen;
int err, flush;
z_stream zst;
if (bufsize < 0) {
PyErr_SetString(PyExc_ValueError, "bufsize must be non-negative");
return NULL;
} else if (bufsize == 0) {
bufsize = 1;
}
ibuf = data->buf;
ibuflen = data->len;
zst.opaque = NULL;
zst.zalloc = PyZlib_Malloc;
zst.zfree = PyZlib_Free;
zst.avail_in = 0;
zst.next_in = ibuf;
err = inflateInit2(&zst, wbits);
switch (err) {
case Z_OK:
break;
case Z_MEM_ERROR:
PyErr_SetString(PyExc_MemoryError,
"Out of memory while decompressing data");
goto error;
default:
inflateEnd(&zst);
zlib_error(zst, err, "while preparing to decompress data");
goto error;
}
do {
arrange_input_buffer(&zst, &ibuflen);
flush = ibuflen == 0 ? Z_FINISH : Z_NO_FLUSH;
do {
bufsize = arrange_output_buffer(&zst, &RetVal, bufsize);
if (bufsize < 0) {
inflateEnd(&zst);
goto error;
}
Py_BEGIN_ALLOW_THREADS
err = inflate(&zst, flush);
Py_END_ALLOW_THREADS
switch (err) {
case Z_OK: /* fall through */
case Z_BUF_ERROR: /* fall through */
case Z_STREAM_END:
break;
case Z_MEM_ERROR:
inflateEnd(&zst);
PyErr_SetString(PyExc_MemoryError,
"Out of memory while decompressing data");
goto error;
default:
inflateEnd(&zst);
zlib_error(zst, err, "while decompressing data");
goto error;
}
} while (zst.avail_out == 0);
} while (err != Z_STREAM_END && ibuflen != 0);
if (err != Z_STREAM_END) {
inflateEnd(&zst);
zlib_error(zst, err, "while decompressing data");
goto error;
}
err = inflateEnd(&zst);
if (err != Z_OK) {
zlib_error(zst, err, "while finishing decompression");
goto error;
}
if (_PyBytes_Resize(&RetVal, zst.next_out -
(Byte *)PyBytes_AS_STRING(RetVal)) < 0)
goto error;
return RetVal;
error:
Py_XDECREF(RetVal);
return NULL;
}
/*[clinic input]
zlib.compressobj
level: int(c_default="Z_DEFAULT_COMPRESSION") = Z_DEFAULT_COMPRESSION
The compression level (an integer in the range 0-9 or -1; default is
currently equivalent to 6). Higher compression levels are slower,
but produce smaller results.
method: int(c_default="DEFLATED") = DEFLATED
The compression algorithm. If given, this must be DEFLATED.
wbits: int(c_default="MAX_WBITS") = MAX_WBITS
+9 to +15: The base-two logarithm of the window size. Include a zlib
container.
-9 to -15: Generate a raw stream.
+25 to +31: Include a gzip container.
memLevel: int(c_default="DEF_MEM_LEVEL") = DEF_MEM_LEVEL
Controls the amount of memory used for internal compression state.
Valid values range from 1 to 9. Higher values result in higher memory
usage, faster compression, and smaller output.
strategy: int(c_default="Z_DEFAULT_STRATEGY") = Z_DEFAULT_STRATEGY
Used to tune the compression algorithm. Possible values are
Z_DEFAULT_STRATEGY, Z_FILTERED, and Z_HUFFMAN_ONLY.
zdict: Py_buffer = None
The predefined compression dictionary - a sequence of bytes
containing subsequences that are likely to occur in the input data.
Return a compressor object.
[clinic start generated code]*/
static PyObject *
zlib_compressobj_impl(PyObject *module, int level, int method, int wbits,
int memLevel, int strategy, Py_buffer *zdict)
/*[clinic end generated code: output=8b5bed9c8fc3814d input=2fa3d026f90ab8d5]*/
{
compobject *self = NULL;
int err;
if (zdict->buf != NULL && (size_t)zdict->len > UINT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"zdict length does not fit in an unsigned int");
goto error;
}
self = newcompobject(_zlibstate_global->Comptype);
if (self == NULL)
goto error;
self->zst.opaque = NULL;
self->zst.zalloc = PyZlib_Malloc;
self->zst.zfree = PyZlib_Free;
self->zst.next_in = NULL;
self->zst.avail_in = 0;
err = deflateInit2(&self->zst, level, method, wbits, memLevel, strategy);
switch (err) {
case Z_OK:
self->is_initialised = 1;
if (zdict->buf == NULL) {
goto success;
} else {
err = deflateSetDictionary(&self->zst,
zdict->buf, (unsigned int)zdict->len);
switch (err) {
case Z_OK:
goto success;
case Z_STREAM_ERROR:
PyErr_SetString(PyExc_ValueError, "Invalid dictionary");
goto error;
default:
PyErr_SetString(PyExc_ValueError, "deflateSetDictionary()");
goto error;
}
}
case Z_MEM_ERROR:
PyErr_SetString(PyExc_MemoryError,
"Can't allocate memory for compression object");
goto error;
case Z_STREAM_ERROR:
PyErr_SetString(PyExc_ValueError, "Invalid initialization option");
goto error;
default:
zlib_error(self->zst, err, "while creating compression object");
goto error;
}
error:
Py_CLEAR(self);
success:
return (PyObject *)self;
}
static int
set_inflate_zdict(compobject *self)
{
Py_buffer zdict_buf;
int err;
if (PyObject_GetBuffer(self->zdict, &zdict_buf, PyBUF_SIMPLE) == -1) {
return -1;
}
if ((size_t)zdict_buf.len > UINT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"zdict length does not fit in an unsigned int");
PyBuffer_Release(&zdict_buf);
return -1;
}
err = inflateSetDictionary(&self->zst,
zdict_buf.buf, (unsigned int)zdict_buf.len);
PyBuffer_Release(&zdict_buf);
if (err != Z_OK) {
zlib_error(self->zst, err, "while setting zdict");
return -1;
}
return 0;
}
/*[clinic input]
zlib.decompressobj
wbits: int(c_default="MAX_WBITS") = MAX_WBITS
The window buffer size and container format.
zdict: object(c_default="NULL") = b''
The predefined compression dictionary. This must be the same
dictionary as used by the compressor that produced the input data.
Return a decompressor object.
[clinic start generated code]*/
static PyObject *
zlib_decompressobj_impl(PyObject *module, int wbits, PyObject *zdict)
/*[clinic end generated code: output=3069b99994f36906 input=d3832b8511fc977b]*/
{
int err;
compobject *self;
if (zdict != NULL && !PyObject_CheckBuffer(zdict)) {
PyErr_SetString(PyExc_TypeError,
"zdict argument must support the buffer protocol");
return NULL;
}
self = newcompobject(_zlibstate_global->Decomptype);
if (self == NULL)
return NULL;
self->zst.opaque = NULL;
self->zst.zalloc = PyZlib_Malloc;
self->zst.zfree = PyZlib_Free;
self->zst.next_in = NULL;
self->zst.avail_in = 0;
if (zdict != NULL) {
Py_INCREF(zdict);
self->zdict = zdict;
}
err = inflateInit2(&self->zst, wbits);
switch (err) {
case Z_OK:
self->is_initialised = 1;
if (self->zdict != NULL && wbits < 0) {
#ifdef AT_LEAST_ZLIB_1_2_2_1
if (set_inflate_zdict(self) < 0) {
Py_DECREF(self);
return NULL;
}
#else
PyErr_Format(_zlibstate_global->ZlibError,
"zlib version %s does not allow raw inflate with dictionary",
ZLIB_VERSION);
Py_DECREF(self);
return NULL;
#endif
}
return (PyObject *)self;
case Z_STREAM_ERROR:
Py_DECREF(self);
PyErr_SetString(PyExc_ValueError, "Invalid initialization option");
return NULL;
case Z_MEM_ERROR:
Py_DECREF(self);
PyErr_SetString(PyExc_MemoryError,
"Can't allocate memory for decompression object");
return NULL;
default:
zlib_error(self->zst, err, "while creating decompression object");
Py_DECREF(self);
return NULL;
}
}
static void
Dealloc(compobject *self)
{
PyObject *type = (PyObject *)Py_TYPE(self);
PyThread_free_lock(self->lock);
Py_XDECREF(self->unused_data);
Py_XDECREF(self->unconsumed_tail);
Py_XDECREF(self->zdict);
PyObject_Del(self);
Py_DECREF(type);
}
static void
Comp_dealloc(compobject *self)
{
if (self->is_initialised)
deflateEnd(&self->zst);
Dealloc(self);
}
static void
Decomp_dealloc(compobject *self)
{
if (self->is_initialised)
inflateEnd(&self->zst);
Dealloc(self);
}
/*[clinic input]
zlib.Compress.compress
data: Py_buffer
Binary data to be compressed.
/
Returns a bytes object containing compressed data.
After calling this function, some of the input data may still
be stored in internal buffers for later processing.
Call the flush() method to clear these buffers.
[clinic start generated code]*/
static PyObject *
zlib_Compress_compress_impl(compobject *self, Py_buffer *data)
/*[clinic end generated code: output=5d5cd791cbc6a7f4 input=0d95908d6e64fab8]*/
{
PyObject *RetVal = NULL;
Py_ssize_t ibuflen, obuflen = DEF_BUF_SIZE;
int err;
self->zst.next_in = data->buf;
ibuflen = data->len;
ENTER_ZLIB(self);
do {
arrange_input_buffer(&self->zst, &ibuflen);
do {
obuflen = arrange_output_buffer(&self->zst, &RetVal, obuflen);
if (obuflen < 0)
goto error;
Py_BEGIN_ALLOW_THREADS
err = deflate(&self->zst, Z_NO_FLUSH);
Py_END_ALLOW_THREADS
if (err == Z_STREAM_ERROR) {
zlib_error(self->zst, err, "while compressing data");
goto error;
}
} while (self->zst.avail_out == 0);
assert(self->zst.avail_in == 0);
} while (ibuflen != 0);
if (_PyBytes_Resize(&RetVal, self->zst.next_out -
(Byte *)PyBytes_AS_STRING(RetVal)) == 0)
goto success;
error:
Py_CLEAR(RetVal);
success:
LEAVE_ZLIB(self);
return RetVal;
}
/* Helper for objdecompress() and flush(). Saves any unconsumed input data in
self->unused_data or self->unconsumed_tail, as appropriate. */
static int
save_unconsumed_input(compobject *self, Py_buffer *data, int err)
{
if (err == Z_STREAM_END) {
/* The end of the compressed data has been reached. Store the leftover
input data in self->unused_data. */
if (self->zst.avail_in > 0) {
Py_ssize_t old_size = PyBytes_GET_SIZE(self->unused_data);
Py_ssize_t new_size, left_size;
PyObject *new_data;
left_size = (Byte *)data->buf + data->len - self->zst.next_in;
if (left_size > (PY_SSIZE_T_MAX - old_size)) {
PyErr_NoMemory();
return -1;
}
new_size = old_size + left_size;
new_data = PyBytes_FromStringAndSize(NULL, new_size);
if (new_data == NULL)
return -1;
memcpy(PyBytes_AS_STRING(new_data),
PyBytes_AS_STRING(self->unused_data), old_size);
memcpy(PyBytes_AS_STRING(new_data) + old_size,
self->zst.next_in, left_size);
Py_SETREF(self->unused_data, new_data);
self->zst.avail_in = 0;
}
}
if (self->zst.avail_in > 0 || PyBytes_GET_SIZE(self->unconsumed_tail)) {
/* This code handles two distinct cases:
1. Output limit was reached. Save leftover input in unconsumed_tail.
2. All input data was consumed. Clear unconsumed_tail. */
Py_ssize_t left_size = (Byte *)data->buf + data->len - self->zst.next_in;
PyObject *new_data = PyBytes_FromStringAndSize(
(char *)self->zst.next_in, left_size);
if (new_data == NULL)
return -1;
Py_SETREF(self->unconsumed_tail, new_data);
}
return 0;
}
/*[clinic input]
zlib.Decompress.decompress
data: Py_buffer
The binary data to decompress.
/
max_length: ssize_t = 0
The maximum allowable length of the decompressed data.
Unconsumed input data will be stored in
the unconsumed_tail attribute.
Return a bytes object containing the decompressed version of the data.
After calling this function, some of the input data may still be stored in
internal buffers for later processing.
Call the flush() method to clear these buffers.
[clinic start generated code]*/
static PyObject *
zlib_Decompress_decompress_impl(compobject *self, Py_buffer *data,
Py_ssize_t max_length)
/*[clinic end generated code: output=6e5173c74e710352 input=b85a212a012b770a]*/
{
int err = Z_OK;
Py_ssize_t ibuflen, obuflen = DEF_BUF_SIZE, hard_limit;
PyObject *RetVal = NULL;
if (max_length < 0) {
PyErr_SetString(PyExc_ValueError, "max_length must be non-negative");
return NULL;
} else if (max_length == 0)
hard_limit = PY_SSIZE_T_MAX;
else
hard_limit = max_length;
self->zst.next_in = data->buf;
ibuflen = data->len;
/* limit amount of data allocated to max_length */
if (max_length && obuflen > max_length)
obuflen = max_length;
ENTER_ZLIB(self);
do {
arrange_input_buffer(&self->zst, &ibuflen);
do {
obuflen = arrange_output_buffer_with_maximum(&self->zst, &RetVal,
obuflen, hard_limit);
if (obuflen == -2) {
if (max_length > 0) {
goto save;
}
PyErr_NoMemory();
}
if (obuflen < 0) {
goto abort;
}
Py_BEGIN_ALLOW_THREADS
err = inflate(&self->zst, Z_SYNC_FLUSH);
Py_END_ALLOW_THREADS
switch (err) {
case Z_OK: /* fall through */
case Z_BUF_ERROR: /* fall through */
case Z_STREAM_END:
break;
default:
if (err == Z_NEED_DICT && self->zdict != NULL) {
if (set_inflate_zdict(self) < 0)
goto abort;
else
break;
}
goto save;
}
} while (self->zst.avail_out == 0 || err == Z_NEED_DICT);
} while (err != Z_STREAM_END && ibuflen != 0);
save:
if (save_unconsumed_input(self, data, err) < 0)
goto abort;
if (err == Z_STREAM_END) {
/* This is the logical place to call inflateEnd, but the old behaviour
of only calling it on flush() is preserved. */
self->eof = 1;
} else if (err != Z_OK && err != Z_BUF_ERROR) {
/* We will only get Z_BUF_ERROR if the output buffer was full
but there wasn't more output when we tried again, so it is
not an error condition.
*/
zlib_error(self->zst, err, "while decompressing data");
goto abort;
}
if (_PyBytes_Resize(&RetVal, self->zst.next_out -
(Byte *)PyBytes_AS_STRING(RetVal)) == 0)
goto success;
abort:
Py_CLEAR(RetVal);
success:
LEAVE_ZLIB(self);
return RetVal;
}
/*[clinic input]
zlib.Compress.flush
mode: int(c_default="Z_FINISH") = zlib.Z_FINISH
One of the constants Z_SYNC_FLUSH, Z_FULL_FLUSH, Z_FINISH.
If mode == Z_FINISH, the compressor object can no longer be
used after calling the flush() method. Otherwise, more data
can still be compressed.
/
Return a bytes object containing any remaining compressed data.
[clinic start generated code]*/
static PyObject *
zlib_Compress_flush_impl(compobject *self, int mode)
/*[clinic end generated code: output=a203f4cefc9de727 input=73ed066794bd15bc]*/
{
int err;
Py_ssize_t length = DEF_BUF_SIZE;
PyObject *RetVal = NULL;
/* Flushing with Z_NO_FLUSH is a no-op, so there's no point in
doing any work at all; just return an empty string. */
if (mode == Z_NO_FLUSH) {
return PyBytes_FromStringAndSize(NULL, 0);
}
ENTER_ZLIB(self);
self->zst.avail_in = 0;
do {
length = arrange_output_buffer(&self->zst, &RetVal, length);
if (length < 0) {
Py_CLEAR(RetVal);
goto error;
}
Py_BEGIN_ALLOW_THREADS
err = deflate(&self->zst, mode);
Py_END_ALLOW_THREADS
if (err == Z_STREAM_ERROR) {
zlib_error(self->zst, err, "while flushing");
Py_CLEAR(RetVal);
goto error;
}
} while (self->zst.avail_out == 0);
assert(self->zst.avail_in == 0);
/* If mode is Z_FINISH, we also have to call deflateEnd() to free
various data structures. Note we should only get Z_STREAM_END when
mode is Z_FINISH, but checking both for safety*/
if (err == Z_STREAM_END && mode == Z_FINISH) {
err = deflateEnd(&self->zst);
if (err != Z_OK) {
zlib_error(self->zst, err, "while finishing compression");
Py_CLEAR(RetVal);
goto error;
}
else
self->is_initialised = 0;
/* We will only get Z_BUF_ERROR if the output buffer was full
but there wasn't more output when we tried again, so it is
not an error condition.
*/
} else if (err != Z_OK && err != Z_BUF_ERROR) {
zlib_error(self->zst, err, "while flushing");
Py_CLEAR(RetVal);
goto error;
}
if (_PyBytes_Resize(&RetVal, self->zst.next_out -
(Byte *)PyBytes_AS_STRING(RetVal)) < 0)
Py_CLEAR(RetVal);
error:
LEAVE_ZLIB(self);
return RetVal;
}
#ifdef HAVE_ZLIB_COPY
/*[clinic input]
zlib.Compress.copy
Return a copy of the compression object.
[clinic start generated code]*/
static PyObject *
zlib_Compress_copy_impl(compobject *self)
/*[clinic end generated code: output=5144aa153c21e805 input=c656351f94b82718]*/
{
compobject *retval = NULL;
int err;
retval = newcompobject(_zlibstate_global->Comptype);
if (!retval) return NULL;
/* Copy the zstream state
* We use ENTER_ZLIB / LEAVE_ZLIB to make this thread-safe
*/
ENTER_ZLIB(self);
err = deflateCopy(&retval->zst, &self->zst);
switch (err) {
case Z_OK:
break;
case Z_STREAM_ERROR:
PyErr_SetString(PyExc_ValueError, "Inconsistent stream state");
goto error;
case Z_MEM_ERROR:
PyErr_SetString(PyExc_MemoryError,
"Can't allocate memory for compression object");
goto error;
default:
zlib_error(self->zst, err, "while copying compression object");
goto error;
}
Py_INCREF(self->unused_data);
Py_XSETREF(retval->unused_data, self->unused_data);
Py_INCREF(self->unconsumed_tail);
Py_XSETREF(retval->unconsumed_tail, self->unconsumed_tail);
Py_XINCREF(self->zdict);
Py_XSETREF(retval->zdict, self->zdict);
retval->eof = self->eof;
/* Mark it as being initialized */
retval->is_initialised = 1;
LEAVE_ZLIB(self);
return (PyObject *)retval;
error:
LEAVE_ZLIB(self);
Py_XDECREF(retval);
return NULL;