summaryrefslogtreecommitdiffstats
path: root/Python/import.c
blob: 8dadc0ecbd49d6a1c8f719a1408b891c9ed8b5f1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
/***********************************************************
Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
The Netherlands.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI or Corporation for National Research Initiatives or
CNRI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.

While CWI is the initial source for this software, a modified version
is made available by the Corporation for National Research Initiatives
(CNRI) at the Internet address ftp://ftp.python.org.

STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.

******************************************************************/

/* Module definition and import implementation */

#include "allobjects.h"

/* XXX Some of the following are duplicate with allobjects.h... */
#include "node.h"
#include "token.h"
#include "graminit.h"
#include "import.h"
#include "errcode.h"
#include "sysmodule.h"
#include "bltinmodule.h"
#include "pythonrun.h"
#include "marshal.h"
#include "compile.h"
#include "eval.h"
#include "osdefs.h"
#include "importdl.h"
#ifdef macintosh
/* 'argument' is a grammar symbol, but also used in some mac header files */
#undef argument
#include "macglue.h"
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

extern long getmtime(); /* In getmtime.c */

/* Magic word to reject .pyc files generated by other Python versions */
/* Change for each incompatible change */
/* The value of CR and LF is incorporated so if you ever read or write
   a .pyc file in text mode the magic number will be wrong; also, the
   Apple MPW compiler swaps their values, botching string constants */
/* XXX Perhaps the magic number should be frozen and a version field
   added to the .pyc file header? */
/* New way to come up with the magic number: (YEAR-1995), MONTH, DAY */
#define MAGIC (20121 | ((long)'\r'<<16) | ((long)'\n'<<24))

object *import_modules; /* This becomes sys.modules */


/* Initialize things */

void
initimport()
{
	if (import_modules != NULL)
		fatal("duplicate initimport() call");
	if ((import_modules = newdictobject()) == NULL)
		fatal("no mem for dictionary of modules");
	if (Py_OptimizeFlag) {
		/* Replace ".pyc" with ".pyo" in import_filetab */
		struct filedescr *p;
		for (p = import_filetab; p->suffix != NULL; p++) {
			if (strcmp(p->suffix, ".pyc") == 0)
				p->suffix = ".pyo";
		}
	}
}


/* Un-initialize things, as good as we can */

void
doneimport()
{
	if (import_modules != NULL) {
		object *tmp = import_modules;
		import_modules = NULL;
		/* This deletes all modules from sys.modules.
		   When a module is deallocated, it in turn clears its dictionary,
		   thus hopefully breaking any circular references between modules
		   and between a module's dictionary and its functions.
		   Note that "import" will fail while we are cleaning up.
		   */
		mappingclear(tmp);
		DECREF(tmp);
	}
}


/* Helper for pythonrun.c -- return magic number */

long
get_pyc_magic()
{
	return MAGIC;
}


/* Helper for sysmodule.c -- return modules dictionary */

object *
get_modules()
{
	return import_modules;
}


/* Get the module object corresponding to a module name.
   First check the modules dictionary if there's one there,
   if not, create a new one and insert in in the modules dictionary.
   Because the former action is most common, THIS DOES NOT RETURN A
   'NEW' REFERENCE! */

object *
add_module(name)
	char *name;
{
	object *m;

	if (import_modules == NULL) {
		err_setstr(SystemError, "sys.modules has been deleted");
		return NULL;
	}
	if ((m = dictlookup(import_modules, name)) != NULL &&
	    is_moduleobject(m))
		return m;
	m = newmoduleobject(name);
	if (m == NULL)
		return NULL;
	if (dictinsert(import_modules, name, m) != 0) {
		DECREF(m);
		return NULL;
	}
	DECREF(m); /* Yes, it still exists, in modules! */

	return m;
}


/* Execute a code object in a module and return the module object
   WITH INCREMENTED REFERENCE COUNT */

object *
exec_code_module(name, co)
	char *name;
	object *co;
{
	object *m, *d, *v;

	m = add_module(name);
	if (m == NULL)
		return NULL;
	d = getmoduledict(m);
	if (dictlookup(d, "__builtins__") == NULL) {
		if (dictinsert(d, "__builtins__", getbuiltins()) != 0)
			return NULL;
	}
	/* Remember the filename as the __file__ attribute */
	if (dictinsert(d, "__file__", ((codeobject *)co)->co_filename) != 0)
		err_clear(); /* Not important enough to report */
	v = eval_code((codeobject *)co, d, d); /* XXX owner? */
	if (v == NULL)
		return NULL;
	DECREF(v);
	INCREF(m);

	return m;
}


/* Given a pathname for a Python source file, fill a buffer with the
   pathname for the corresponding compiled file.  Return the pathname
   for the compiled file, or NULL if there's no space in the buffer.
   Doesn't set an exception. */

static char *
make_compiled_pathname(pathname, buf, buflen)
	char *pathname;
	char *buf;
	int buflen;
{
	int len;

	len = strlen(pathname);
	if (len+2 > buflen)
		return NULL;
	strcpy(buf, pathname);
	strcpy(buf+len, Py_OptimizeFlag ? "o" : "c");

	return buf;
}


/* Given a pathname for a Python source file, its time of last
   modification, and a pathname for a compiled file, check whether the
   compiled file represents the same version of the source.  If so,
   return a FILE pointer for the compiled file, positioned just after
   the header; if not, return NULL.
   Doesn't set an exception. */

static FILE *
check_compiled_module(pathname, mtime, cpathname)
	char *pathname;
	long mtime;
	char *cpathname;
{
	FILE *fp;
	long magic;
	long pyc_mtime;

	fp = fopen(cpathname, "rb");
	if (fp == NULL)
		return NULL;
	magic = rd_long(fp);
	if (magic != MAGIC) {
		if (verbose)
			fprintf(stderr, "# %s has bad magic\n", cpathname);
		fclose(fp);
		return NULL;
	}
	pyc_mtime = rd_long(fp);
	if (pyc_mtime != mtime) {
		if (verbose)
			fprintf(stderr, "# %s has bad mtime\n", cpathname);
		fclose(fp);
		return NULL;
	}
	if (verbose)
		fprintf(stderr, "# %s matches %s\n", cpathname, pathname);
	return fp;
}


/* Read a code object from a file and check it for validity */

static codeobject *
read_compiled_module(fp)
	FILE *fp;
{
	object *co;

	co = rd_object(fp);
	/* Ugly: rd_object() may return NULL with or without error */
	if (co == NULL || !is_codeobject(co)) {
		if (!err_occurred())
			err_setstr(ImportError,
				   "Non-code object in .pyc file");
		XDECREF(co);
		return NULL;
	}
	return (codeobject *)co;
}


/* Load a module from a compiled file, execute it, and return its
   module object WITH INCREMENTED REFERENCE COUNT */

static object *
load_compiled_module(name, cpathname, fp)
	char *name;
	char *cpathname;
	FILE *fp;
{
	long magic;
	codeobject *co;
	object *m;

	magic = rd_long(fp);
	if (magic != MAGIC) {
		err_setstr(ImportError, "Bad magic number in .pyc file");
		return NULL;
	}
	(void) rd_long(fp);
	co = read_compiled_module(fp);
	if (co == NULL)
		return NULL;
	if (verbose)
		fprintf(stderr, "import %s # precompiled from %s\n",
			name, cpathname);
	m = exec_code_module(name, (object *)co);
	DECREF(co);

	return m;
}

/* Parse a source file and return the corresponding code object */

static codeobject *
parse_source_module(pathname, fp)
	char *pathname;
	FILE *fp;
{
	codeobject *co;
	node *n;

	n = parse_file(fp, pathname, file_input);
	if (n == NULL)
		return NULL;
	co = compile(n, pathname);
	freetree(n);

	return co;
}


/* Write a compiled module to a file, placing the time of last
   modification of its source into the header.
   Errors are ignored, if a write error occurs an attempt is made to
   remove the file. */

static void
write_compiled_module(co, cpathname, mtime)
	codeobject *co;
	char *cpathname;
	long mtime;
{
	FILE *fp;

	fp = fopen(cpathname, "wb");
	if (fp == NULL) {
		if (verbose)
			fprintf(stderr,
				"# can't create %s\n", cpathname);
		return;
	}
	wr_long(MAGIC, fp);
	/* First write a 0 for mtime */
	wr_long(0L, fp);
	wr_object((object *)co, fp);
	if (ferror(fp)) {
		if (verbose)
			fprintf(stderr, "# can't write %s\n", cpathname);
		/* Don't keep partial file */
		fclose(fp);
		(void) unlink(cpathname);
		return;
	}
	/* Now write the true mtime */
	fseek(fp, 4L, 0);
	wr_long(mtime, fp);
	fflush(fp);
	fclose(fp);
	if (verbose)
		fprintf(stderr, "# wrote %s\n", cpathname);
#ifdef macintosh
	setfiletype(cpathname, 'Pyth', 'PYC ');
#endif
}


/* Load a source module from a given file and return its module
   object WITH INCREMENTED REFERENCE COUNT.  If there's a matching
   byte-compiled file, use that instead. */

static object *
load_source_module(name, pathname, fp)
	char *name;
	char *pathname;
	FILE *fp;
{
	long mtime;
	FILE *fpc;
	char buf[MAXPATHLEN+1];
	char *cpathname;
	codeobject *co;
	object *m;

	mtime = getmtime(pathname);
	cpathname = make_compiled_pathname(pathname, buf, MAXPATHLEN+1);
	if (cpathname != NULL &&
	    (fpc = check_compiled_module(pathname, mtime, cpathname))) {
		co = read_compiled_module(fpc);
		fclose(fpc);
		if (co == NULL)
			return NULL;
		if (verbose)
			fprintf(stderr, "import %s # precompiled from %s\n",
				name, cpathname);
	}
	else {
		co = parse_source_module(pathname, fp);
		if (co == NULL)
			return NULL;
		if (verbose)
			fprintf(stderr, "import %s # from %s\n",
				name, pathname);
		write_compiled_module(co, cpathname, mtime);
	}
	m = exec_code_module(name, (object *)co);
	DECREF(co);

	return m;
}


/* Search the path (default sys.path) for a module.  Return the
   corresponding filedescr struct, and (via return arguments) the
   pathname and an open file.  Return NULL if the module is not found. */

static struct filedescr *
find_module(name, path, buf, buflen, p_fp)
	char *name;
	object *path;
	/* Output parameters: */
	char *buf;
	int buflen;
	FILE **p_fp;
{
	int i, npath, len, namelen;
	struct filedescr *fdp = NULL;
	FILE *fp = NULL;

#ifdef MS_COREDLL
	extern FILE *PyWin_FindRegisteredModule();
	if ((fp=PyWin_FindRegisteredModule(name, &fdp, buf, buflen))!=NULL) {
		*p_fp = fp;
		return fdp;
	}
#endif


	if (path == NULL)
		path = sysget("path");
	if (path == NULL || !is_listobject(path)) {
		err_setstr(ImportError,
			   "sys.path must be a list of directory names");
		return NULL;
	}
	npath = getlistsize(path);
	namelen = strlen(name);
	for (i = 0; i < npath; i++) {
		object *v = getlistitem(path, i);
		if (!is_stringobject(v))
			continue;
		len = getstringsize(v);
		if (len + 2 + namelen + import_maxsuffixsize >= buflen)
			continue; /* Too long */
		strcpy(buf, getstringvalue(v));
		if ((int)strlen(buf) != len)
			continue; /* v contains '\0' */
#ifdef macintosh
		if ( PyMac_FindResourceModule(name, buf) ) {
			static struct filedescr resfiledescr = { "", "", PY_RESOURCE};
			
			return &resfiledescr;
		}
#endif
		if (len > 0 && buf[len-1] != SEP)
			buf[len++] = SEP;
#ifdef IMPORT_8x3_NAMES
		/* see if we are searching in directory dos_8x3 */
		if (len > 7 && !strncmp(buf + len - 8, "dos_8x3", 7)){
			int j;
			char ch;  /* limit name to eight lower-case characters */
			for (j = 0; (ch = name[j]) && j < 8; j++)
				if (isupper(ch))
					buf[len++] = tolower(ch);
				else
					buf[len++] = ch;
		}
		else /* Not in dos_8x3, use the full name */
#endif
		{
			strcpy(buf+len, name);
			len += namelen;
		}
		for (fdp = import_filetab; fdp->suffix != NULL; fdp++) {
			strcpy(buf+len, fdp->suffix);
			if (verbose > 1)
				fprintf(stderr, "# trying %s\n", buf);
			fp = fopen(buf, fdp->mode);
			if (fp != NULL)
				break;
		}
		if (fp != NULL)
			break;
	}
	if (fp == NULL) {
		char buf[256];
		sprintf(buf, "No module named %.200s", name);
		err_setstr(ImportError, buf);
		return NULL;
	}

	*p_fp = fp;
	return fdp;
}


/* Load an external module using the default search path and return
   its module object WITH INCREMENTED REFERENCE COUNT */

static object *
load_module(name)
	char *name;
{
	char buf[MAXPATHLEN+1];
	struct filedescr *fdp;
	FILE *fp = NULL;
	object *m;

	fdp = find_module(name, (object *)NULL, buf, MAXPATHLEN+1, &fp);
	if (fdp == NULL)
		return NULL;

	switch (fdp->type) {

	case PY_SOURCE:
		m = load_source_module(name, buf, fp);
		break;

	case PY_COMPILED:
		m = load_compiled_module(name, buf, fp);
		break;

	case C_EXTENSION:
		m = load_dynamic_module(name, buf, fp);
		break;

#ifdef macintosh
	case PY_RESOURCE:
		m = PyMac_LoadResourceModule(name, buf);
		break;
#endif

	default:
		err_setstr(SystemError,
			   "find_module returned unexpected result");
		m = NULL;

	}
	if ( fp )
		fclose(fp);

	return m;
}


/* Initialize a built-in module.
   Return 1 for succes, 0 if the module is not found, and -1 with
   an exception set if the initialization failed. */

static int
init_builtin(name)
	char *name;
{
	int i;
	for (i = 0; inittab[i].name != NULL; i++) {
		if (strcmp(name, inittab[i].name) == 0) {
			if (inittab[i].initfunc == NULL) {
				err_setstr(ImportError,
					   "Cannot re-init internal module");
				return -1;
			}
			if (verbose)
				fprintf(stderr, "import %s # builtin\n",
					name);
			(*inittab[i].initfunc)();
			if (err_occurred())
				return -1;
			return 1;
		}
	}
	return 0;
}


/* Frozen modules */

static struct _frozen *
find_frozen(name)
	char *name;
{
	struct _frozen *p;

	for (p = frozen_modules; ; p++) {
		if (p->name == NULL)
			return NULL;
		if (strcmp(p->name, name) == 0)
			break;
	}
	return p;
}

static object *
get_frozen_object(name)
	char *name;
{
	struct _frozen *p = find_frozen(name);

	if (p == NULL) {
		err_setstr(ImportError, "No such frozen object");
		return NULL;
	}
	return rds_object((char *)p->code, p->size);
}

/* Initialize a frozen module.
   Return 1 for succes, 0 if the module is not found, and -1 with
   an exception set if the initialization failed.
   This function is also used from frozenmain.c */

int
init_frozen(name)
	char *name;
{
	struct _frozen *p = find_frozen(name);
	object *co;
	object *m;

	if (p == NULL)
		return 0;
	if (verbose)
		fprintf(stderr, "import %s # frozen\n", name);
	co = rds_object((char *)p->code, p->size);
	if (co == NULL)
		return -1;
	if (!is_codeobject(co)) {
		DECREF(co);
		err_setstr(TypeError, "frozen object is not a code object");
		return -1;
	}
	m = exec_code_module(name, co);
	DECREF(co);
	if (m == NULL)
		return -1;
	DECREF(m);
	return 1;
}


/* Import a module, either built-in, frozen, or external, and return
   its module object WITH INCREMENTED REFERENCE COUNT */

object *
import_module(name)
	char *name;
{
	object *m;

	if (import_modules == NULL) {
		err_setstr(SystemError, "sys.modules has been deleted");
		return NULL;
	}
	if ((m = dictlookup(import_modules, name)) != NULL) {
		INCREF(m);
	}
	else {
		int i;
		if ((i = init_builtin(name)) || (i = init_frozen(name))) {
			if (i < 0)
				return NULL;
			if ((m = dictlookup(import_modules, name)) == NULL) {
			    if (err_occurred() == NULL)
			        err_setstr(SystemError,
				 "built-in module not initialized properly");
			}
			else
				INCREF(m);
		}
		else
			m = load_module(name);
	}

	return m;
}


/* Re-import a module of any kind and return its module object, WITH
   INCREMENTED REFERENCE COUNT */

object *
reload_module(m)
	object *m;
{
	char *name;
	int i;

	if (m == NULL || !is_moduleobject(m)) {
		err_setstr(TypeError, "reload() argument must be module");
		return NULL;
	}
	name = getmodulename(m);
	if (name == NULL)
		return NULL;
	if (import_modules == NULL) {
		err_setstr(SystemError, "sys.modules has been deleted");
		return NULL;
	}
	if (m != dictlookup(import_modules, name)) {
		err_setstr(ImportError, "reload() module not in sys.modules");
		return NULL;
	}
	/* Check for built-in and frozen modules */
	if ((i = init_builtin(name)) || (i = init_frozen(name))) {
		if (i < 0)
			return NULL;
		INCREF(m);
	}
	else
		m = load_module(name);
	return m;
}


/* Module 'imp' provides Python access to the primitives used for
   importing modules.
*/

static object *
imp_get_magic(self, args)
	object *self;
	object *args;
{
	char buf[4];

	if (!newgetargs(args, ""))
		return NULL;
	buf[0] = (char) ((MAGIC >>  0) & 0xff);
	buf[1] = (char) ((MAGIC >>  8) & 0xff);
	buf[2] = (char) ((MAGIC >> 16) & 0xff);
	buf[3] = (char) ((MAGIC >> 24) & 0xff);

	return newsizedstringobject(buf, 4);
}

static object *
imp_get_suffixes(self, args)
	object *self;
	object *args;
{
	object *list;
	struct filedescr *fdp;

	if (!newgetargs(args, ""))
		return NULL;
	list = newlistobject(0);
	if (list == NULL)
		return NULL;
	for (fdp = import_filetab; fdp->suffix != NULL; fdp++) {
		object *item = mkvalue("ssi",
				       fdp->suffix, fdp->mode, fdp->type);
		if (item == NULL) {
			DECREF(list);
			return NULL;
		}
		if (addlistitem(list, item) < 0) {
			DECREF(list);
			DECREF(item);
			return NULL;
		}
		DECREF(item);
	}
	return list;
}

static object *
imp_find_module(self, args)
	object *self;
	object *args;
{
	extern int fclose PROTO((FILE *));
	char *name;
	object *path = NULL;
	object *fob, *ret;
	struct filedescr *fdp;
	char pathname[MAXPATHLEN+1];
	FILE *fp;
	if (!newgetargs(args, "s|O!", &name, &Listtype, &path))
		return NULL;
	fdp = find_module(name, path, pathname, MAXPATHLEN+1, &fp);
	if (fdp == NULL)
		return NULL;
	fob = newopenfileobject(fp, pathname, fdp->mode, fclose);
	if (fob == NULL) {
		fclose(fp);
		return NULL;
	}
	ret = mkvalue("Os(ssi)",
		      fob, pathname, fdp->suffix, fdp->mode, fdp->type);
	DECREF(fob);
	return ret;
}

static object *
imp_init_builtin(self, args)
	object *self;
	object *args;
{
	char *name;
	int ret;
	object *m;
	if (!newgetargs(args, "s", &name))
		return NULL;
	ret = init_builtin(name);
	if (ret < 0)
		return NULL;
	if (ret == 0) {
		INCREF(None);
		return None;
	}
	m = add_module(name);
	XINCREF(m);
	return m;
}

static object *
imp_init_frozen(self, args)
	object *self;
	object *args;
{
	char *name;
	int ret;
	object *m;
	if (!newgetargs(args, "s", &name))
		return NULL;
	ret = init_frozen(name);
	if (ret < 0)
		return NULL;
	if (ret == 0) {
		INCREF(None);
		return None;
	}
	m = add_module(name);
	XINCREF(m);
	return m;
}

static object *
imp_get_frozen_object(self, args)
	object *self;
	object *args;
{
	char *name;

	if (!newgetargs(args, "s", &name))
		return NULL;
	return get_frozen_object(name);
}

static object *
imp_is_builtin(self, args)
	object *self;
	object *args;
{
	int i;
	char *name;
	if (!newgetargs(args, "s", &name))
		return NULL;
	for (i = 0; inittab[i].name != NULL; i++) {
		if (strcmp(name, inittab[i].name) == 0) {
			if (inittab[i].initfunc == NULL)
				return newintobject(-1);
			else
				return newintobject(1);
		}
	}
	return newintobject(0);
}

static object *
imp_is_frozen(self, args)
	object *self;
	object *args;
{
	struct _frozen *p;
	char *name;
	if (!newgetargs(args, "s", &name))
		return NULL;
	for (p = frozen_modules; ; p++) {
		if (p->name == NULL)
			break;
		if (strcmp(p->name, name) == 0)
			return newintobject(1);
	}
	return newintobject(0);
}

static FILE *
get_file(pathname, fob, mode)
	char *pathname;
	object *fob;
	char *mode;
{
	FILE *fp;
	if (fob == NULL) {
		fp = fopen(pathname, mode);
		if (fp == NULL)
			err_errno(IOError);
	}
	else {
		fp = getfilefile(fob);
		if (fp == NULL)
			err_setstr(ValueError, "bad/closed file object");
	}
	return fp;
}

static object *
imp_load_compiled(self, args)
	object *self;
	object *args;
{
	char *name;
	char *pathname;
	object *fob = NULL;
	object *m;
	FILE *fp;
	if (!newgetargs(args, "ssO!", &name, &pathname, &Filetype, &fob))
		return NULL;
	fp = get_file(pathname, fob, "rb");
	if (fp == NULL)
		return NULL;
	m = load_compiled_module(name, pathname, fp);
	return m;
}

static object *
imp_load_dynamic(self, args)
	object *self;
	object *args;
{
	char *name;
	char *pathname;
	object *fob = NULL;
	object *m;
	FILE *fp = NULL;
	if (!newgetargs(args, "ss|O!", &name, &pathname, &Filetype, &fob))
		return NULL;
	if (fob)
		fp = get_file(pathname, fob, "r");
	m = load_dynamic_module(name, pathname, fp);
	return m;
}

static object *
imp_load_source(self, args)
	object *self;
	object *args;
{
	char *name;
	char *pathname;
	object *fob = NULL;
	object *m;
	FILE *fp;
	if (!newgetargs(args, "ssO!", &name, &pathname, &Filetype, &fob))
		return NULL;
	fp = get_file(pathname, fob, "r");
	if (fp == NULL)
		return NULL;
	m = load_source_module(name, pathname, fp);
	return m;
}

#ifdef macintosh
static object *
imp_load_resource(self, args)
	object *self;
	object *args;
{
	char *name;
	char *pathname;
	object *m;

	if (!newgetargs(args, "ss", &name, &pathname))
		return NULL;
	m = PyMac_LoadResourceModule(name, pathname);
	return m;
}
#endif /* macintosh */

static object *
imp_new_module(self, args)
	object *self;
	object *args;
{
	char *name;
	if (!newgetargs(args, "s", &name))
		return NULL;
	return newmoduleobject(name);
}

static struct methodlist imp_methods[] = {
	{"get_frozen_object",	imp_get_frozen_object,	1},
	{"get_magic",		imp_get_magic,		1},
	{"get_suffixes",	imp_get_suffixes,	1},
	{"find_module",		imp_find_module,	1},
	{"init_builtin",	imp_init_builtin,	1},
	{"init_frozen",		imp_init_frozen,	1},
	{"is_builtin",		imp_is_builtin,		1},
	{"is_frozen",		imp_is_frozen,		1},
	{"load_compiled",	imp_load_compiled,	1},
	{"load_dynamic",	imp_load_dynamic,	1},
	{"load_source",		imp_load_source,	1},
	{"new_module",		imp_new_module,		1},
#ifdef macintosh
	{"load_resource",	imp_load_resource,	1},
#endif
	{NULL,			NULL}		/* sentinel */
};

void
initimp()
{
	object *m, *d, *v;

	m = initmodule("imp", imp_methods);
	d = getmoduledict(m);

	v = newintobject(SEARCH_ERROR);
	dictinsert(d, "SEARCH_ERROR", v);
	XDECREF(v);

	v = newintobject(PY_SOURCE);
	dictinsert(d, "PY_SOURCE", v);
	XDECREF(v);

	v = newintobject(PY_COMPILED);
	dictinsert(d, "PY_COMPILED", v);
	XDECREF(v);

	v = newintobject(C_EXTENSION);
	dictinsert(d, "C_EXTENSION", v);
	XDECREF(v);

#ifdef macintosh
	v = newintobject(PY_RESOURCE);
	dictinsert(d, "PY_RESOURCE", v);
	XDECREF(v);
#endif


	if (err_occurred())
		fatal("imp module initialization failed");
}