summaryrefslogtreecommitdiff
path: root/ext/iconv/iconv.c
blob: 53277978566c7c2627fa638ee5a855e569d6abe3 (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
/* -*- mode:c; c-file-style:"ruby" -*- */
/**********************************************************************

  iconv.c -

  $Author$
  $Date$
  created at: Wed Dec  1 20:28:09 JST 1999

  All the files in this distribution are covered under the Ruby's
  license (see the file COPYING).

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

/*
=begin
= Summary
Ruby extension for codeset conversion.

= Abstract
Iconv is a wrapper class for UNIX 95 (({iconv()})) function family, which
translates string between various coding systems.

See ((<Open Group|URL:http://www.opengroup.org/>))'s on-line documents for more details.
* ((<iconv.h|URL:http://www.opengroup.org/onlinepubs/007908799/xsh/iconv.h.html>))
* ((<iconv_open()|URL:http://www.opengroup.org/onlinepubs/007908799/xsh/iconv_open.html>))
* ((<iconv()|URL:http://www.opengroup.org/onlinepubs/007908799/xsh/iconv.html>))
* ((<iconv_close()|URL:http://www.opengroup.org/onlinepubs/007908799/xsh/iconv_close.html>))

Which coding systems are available, it depends on the platform.

=end
*/

#include "ruby.h"
#include <errno.h>
#include <iconv.h>
#include <assert.h>
#include "st.h"
#include "intern.h"

/* Invalid value for iconv_t is -1 but 0 for VALUE, I hope VALUE is
   big enough to keep iconv_t */
#define VALUE2ICONV(v) ((iconv_t)((VALUE)(v) ^ -1))
#define ICONV2VALUE(c) ((VALUE)(c) ^ -1)

struct iconv_env_t
{
    iconv_t cd;
    int argc;
    VALUE *argv;
    VALUE ret;
    VALUE (*append)_((VALUE, VALUE));
};

static VALUE rb_eIconvFailure;
static VALUE rb_eIconvIllegalSeq;
static VALUE rb_eIconvInvalidChar;
static VALUE rb_eIconvOutOfRange;

static ID rb_success, rb_failed;
static VALUE iconv_fail _((VALUE error, VALUE success, VALUE failed, struct iconv_env_t* env, const char *mesg));
static VALUE iconv_failure_initialize _((VALUE error, VALUE mesg, VALUE success, VALUE failed));
static VALUE iconv_failure_success _((VALUE self));
static VALUE iconv_failure_failed _((VALUE self));

static iconv_t iconv_create _((VALUE to, VALUE from));
static void iconv_dfree _((void *cd));
static VALUE iconv_free _((VALUE cd));
static VALUE iconv_try _((iconv_t cd, const char **inptr, size_t *inlen, char **outptr, size_t *outlen));
static VALUE rb_str_derive _((VALUE str, const char* ptr, int len));
static VALUE iconv_convert _((iconv_t cd, VALUE str, int start, int length, struct iconv_env_t* env));
static VALUE iconv_s_allocate _((VALUE klass));
static VALUE iconv_initialize _((VALUE self, VALUE to, VALUE from));
static VALUE iconv_s_open _((VALUE self, VALUE to, VALUE from));
static VALUE iconv_s_convert _((struct iconv_env_t* env));
static VALUE iconv_s_iconv _((int argc, VALUE *argv, VALUE self));
static VALUE iconv_init_state _((VALUE cd));
static VALUE iconv_finish _((VALUE self));
static VALUE iconv_iconv _((int argc, VALUE *argv, VALUE self));


/*
=begin
= Classes & Modules
=end
*/

/*
=begin
== Iconv
=end
*/
static VALUE charset_map;

static VALUE charset_map_get _((void))
{
    return charset_map;
}

static char *
map_charset
#ifdef HAVE_PROTOTYPES
    (VALUE *code)
#else /* HAVE_PROTOTYPES */
    (code)
    VALUE *code;
#endif /* HAVE_PROTOTYPES */
{
    VALUE val = *code;

    if (RHASH(charset_map)->tbl && RHASH(charset_map)->tbl->num_entries) {
	VALUE key = rb_funcall2(val, rb_intern("downcase"), 0, 0);
	StringValuePtr(key);
	if (st_lookup(RHASH(charset_map)->tbl, key, &val)) {
	    StringValuePtr(val);
	    *code = val;
	}
    }
    else {
	StringValuePtr(val);
    }
    return RSTRING(val)->ptr;
}

static iconv_t
iconv_create
#ifdef HAVE_PROTOTYPES
    (VALUE to, VALUE from)
#else /* HAVE_PROTOTYPES */
    (to, from)
    VALUE to;
    VALUE from;
#endif /* HAVE_PROTOTYPES */
{
    const char* tocode = map_charset(&to);
    const char* fromcode = map_charset(&from);

    iconv_t cd = iconv_open(tocode, fromcode);

    if (cd == (iconv_t)-1) {
	switch (errno) {
	  case EMFILE:
	  case ENFILE:
	  case ENOMEM:
	    rb_gc();
	    cd = iconv_open(tocode, fromcode);
	}
	if (cd == (iconv_t)-1) {
	    volatile VALUE msg = rb_str_new2("iconv(\"");
	    rb_str_buf_cat2(rb_str_buf_append(msg, to), "\", \"");
	    rb_str_buf_cat2(rb_str_buf_append(msg, from), "\")");
	    rb_sys_fail(StringValuePtr(msg));
	}
    }

    return cd;
}

static void
iconv_dfree
#ifdef HAVE_PROTOTYPES
    (void *cd)
#else /* HAVE_PROTOTYPES */
    (cd)
    void *cd;
#endif /* HAVE_PROTOTYPES */
{
    iconv_close(VALUE2ICONV(cd));
}

#define ICONV_FREE iconv_dfree

static VALUE
iconv_free
#ifdef HAVE_PROTOTYPES
    (VALUE cd)
#else /* HAVE_PROTOTYPES */
    (cd)
    VALUE cd;
#endif /* HAVE_PROTOTYPES */
{
    if (cd && iconv_close(VALUE2ICONV(cd)) == -1)
	rb_sys_fail("iconv_close");
    return Qnil;
}

static VALUE
check_iconv
#ifdef HAVE_PROTOTYPES
    (VALUE obj)
#else /* HAVE_PROTOTYPES */
    (obj)
    VALUE obj;
#endif /* HAVE_PROTOTYPES */
{
    Check_Type(obj, T_DATA);
    if (RDATA(obj)->dfree != ICONV_FREE) {
	rb_raise(rb_eArgError, "Iconv expected (%s)", rb_class2name(CLASS_OF(obj)));
    }
    return (VALUE)DATA_PTR(obj);
}

static VALUE
iconv_try
#ifdef HAVE_PROTOTYPES
    (iconv_t cd, const char **inptr, size_t *inlen, char **outptr, size_t *outlen)
#else /* HAVE_PROTOTYPES */
    (cd, inptr, inlen, outptr, outlen)
    iconv_t cd;
    const char **inptr;
    size_t *inlen;
    char **outptr;
    size_t *outlen;
#endif /* HAVE_PROTOTYPES */
{
    size_t ret = iconv(cd, ICONV_INPTR_CAST inptr, inlen, outptr, outlen);
    if (ret == (size_t)-1) {
	if (!*inlen)
	    return Qfalse;
	switch (errno) {
	  case E2BIG:
	    /* try the left in next loop */
	    break;
	  case EILSEQ:
	    return rb_eIconvIllegalSeq;
	  case EINVAL:
	    return rb_eIconvInvalidChar;
	  default:
	    rb_sys_fail("iconv");
	}
    }
    else if (*inlen > 0) {
	/* something goes wrong */
	return rb_eIconvIllegalSeq;
    }
    else if (ret) {
	return Qnil;		/* conversion */
    }
    return Qfalse;
}

#define FAILED_MAXLEN 16

static VALUE iconv_failure_initialize
#ifdef HAVE_PROTOTYPES
    (VALUE error, VALUE mesg, VALUE success, VALUE failed)
#else /* HAVE_PROTOTYPES */
    (error, mesg, success, failed)
    VALUE error, mesg, success, failed;
#endif /* HAVE_PROTOTYPES */
{
    rb_call_super(1, &mesg);
    rb_ivar_set(error, rb_success, success);
    rb_ivar_set(error, rb_failed, failed);
    return error;
}

static VALUE
iconv_fail
#ifdef HAVE_PROTOTYPES
    (VALUE error, VALUE success, VALUE failed, struct iconv_env_t* env, const char *mesg)
#else /* HAVE_PROTOTYPES */
    (error, success, failed, env, mesg)
    VALUE error, success, failed;
    struct iconv_env_t *env;
    const char *mesg;
#endif /* HAVE_PROTOTYPES */
{
    VALUE args[3];

    if (mesg && *mesg) {
	args[0] = rb_str_new2(mesg);
    }
    else if (TYPE(failed) != T_STRING || RSTRING(failed)->len < FAILED_MAXLEN) {
	args[0] = rb_inspect(failed);
    }
    else {
	args[0] = rb_inspect(rb_str_substr(failed, 0, FAILED_MAXLEN));
	rb_str_cat2(args[0], "...");
    }
    args[1] = success;
    args[2] = failed;
    if (env) {
	args[1] = env->append(rb_obj_dup(env->ret), success);
	if (env->argc > 0) {
	    *(env->argv) = failed;
	    args[2] = rb_ary_new4(env->argc, env->argv);
	}
    }
    error = rb_class_new_instance(3, args, error);
    if (!rb_block_given_p()) rb_exc_raise(error);
    ruby_errinfo = error;
    return rb_yield(failed);
}

static VALUE
rb_str_derive
#ifdef HAVE_PROTOTYPES
    (VALUE str, const char* ptr, int len)
#else /* HAVE_PROTOTYPES */
    (str, ptr, len)
    VALUE str;
    const char *ptr;
    int len;
#endif /* HAVE_PROTOTYPES */
{
    VALUE ret;

    if (NIL_P(str))
	return rb_str_new(ptr, len);
    if (RSTRING(str)->ptr == ptr && RSTRING(str)->len == len)
	return str;
    if (RSTRING(str)->ptr + RSTRING(str)->len == ptr + len)
	ret = rb_str_substr(str, ptr - RSTRING(str)->ptr, len);
    else
	ret = rb_str_new(ptr, len);
    OBJ_INFECT(ret, str);
    return ret;
}

static VALUE
iconv_convert
#ifdef HAVE_PROTOTYPES
    (iconv_t cd, VALUE str, int start, int length, struct iconv_env_t* env)
#else /* HAVE_PROTOTYPES */
    (cd, str, start, length, env)
    iconv_t cd;
    VALUE str;
    int start;
    int length;
    struct iconv_env_t *env;
#endif /* HAVE_PROTOTYPES */
{
    VALUE ret = Qfalse;
    VALUE error = Qfalse;
    VALUE rescue;
    const char *inptr, *instart;
    size_t inlen;
    /* I believe ONE CHARACTER never exceed this. */
    char buffer[BUFSIZ];
    char *outptr;
    size_t outlen;

    if (cd == (iconv_t)-1)
	rb_raise(rb_eArgError, "closed iconv");

    if (NIL_P(str)) {
	/* Reset output pointer or something. */
	inptr = "";
	inlen = 0;
	outptr = buffer;
	outlen = sizeof(buffer);
	error = iconv_try(cd, &inptr, &inlen, &outptr, &outlen);
	if (RTEST(error)) {
	    unsigned int i;
	    rescue = iconv_fail(error, Qnil, Qnil, env, 0);
	    if (TYPE(rescue) == T_ARRAY) {
		str = RARRAY(rescue)->len > 0 ? RARRAY(rescue)->ptr[0] : Qnil;
	    }
	    if (FIXNUM_P(str) && (i = FIX2INT(str)) <= 0xff) {
		char c = i;
		str = rb_str_new(&c, 1);
	    }
	    else if (!NIL_P(str)) {
		StringValue(str);
	    }
	}

	inptr = NULL;
	length = 0;
    }
    else {
	int slen;

	StringValue(str);
	slen = RSTRING(str)->len;
	inptr = RSTRING(str)->ptr;

	if (start < 0 ? (start += slen) < 0 : start >= slen)
	    length = 0;
	else if (length < 0 && (length += slen + 1) < 0)
	    length = 0;
	else if ((length -= start) < 0)
	    length = 0;
	else
	    inptr += start;
    }
    instart = inptr;
    inlen = length;

    do {
	char errmsg[50];
	const char *tmpstart = inptr;
	outptr = buffer;
	outlen = sizeof(buffer);

	errmsg[0] = 0;
	error = iconv_try(cd, &inptr, &inlen, &outptr, &outlen);

	if (0 <= outlen && outlen <= sizeof(buffer)) {
	    outlen = sizeof(buffer) - outlen;
	    if (NIL_P(error) ||	/* something converted */
		outlen > inptr - tmpstart || /* input can't contain output */
		(outlen < inptr - tmpstart && inlen > 0) || /* something skipped */
		memcmp(buffer, tmpstart, outlen)) /* something differs */
	    {
		if (NIL_P(str)) {
		    ret = rb_str_new(buffer, outlen);
		}
		else {
		    if (ret) {
			ret = rb_str_buf_cat(ret, instart, tmpstart - instart);
		    }
		    else {
			ret = rb_str_new(instart, tmpstart - instart);
			OBJ_INFECT(ret, str);
		    }
		    ret = rb_str_buf_cat(ret, buffer, outlen);
		    instart = inptr;
		}
	    }
	    else if (!inlen) {
		inptr = tmpstart + outlen;
	    }
	}
	else {
	    /* Some iconv() have a bug, return *outlen out of range */
	    sprintf(errmsg, "bug?(output length = %ld)", sizeof(buffer) - outlen);
	    error = rb_eIconvOutOfRange;
	}

	if (RTEST(error)) {
	    long len = 0;

	    if (!ret)
		ret = rb_str_derive(str, instart, inptr - instart);
	    else if (inptr > instart)
		rb_str_cat(ret, instart, inptr - instart);
	    str = rb_str_derive(str, inptr, inlen);
	    rescue = iconv_fail(error, ret, str, env, errmsg);
	    if (TYPE(rescue) == T_ARRAY) {
		if ((len = RARRAY(rescue)->len) > 0)
		    rb_str_concat(ret, RARRAY(rescue)->ptr[0]);
		if (len > 1 && !NIL_P(str = RARRAY(rescue)->ptr[1])) {
		    StringValue(str);
		    inlen = length = RSTRING(str)->len;
		    instart = inptr = RSTRING(str)->ptr;
		    continue;
		}
	    }
	    else if (!NIL_P(rescue)) {
		rb_str_concat(ret, rescue);
	    }
	    break;
	}
    } while (inlen > 0);

    if (!ret)
	ret = rb_str_derive(str, instart, inptr - instart);
    else if (inptr > instart)
	rb_str_cat(ret, instart, inptr - instart);
    return ret;
}


/*
=begin
=== Class methods
=end
*/
/*
=begin
--- Iconv.new(to, from) {|cd| ...}
    Creates new code converter from a coding-system designated with ((|from|))
    to another one designated with ((|to|)).
    :Parameters
      :((|to|))
        coding-system name for destination.
      :((|from|))
        coding-system name for source.
    :Exceptions
      :(({TypeError}))
        if ((|to|)) or ((|from|)) aren't String
      :(({ArgumentError}))
        if designated converter couldn't find out.
      :(({SystemCallError}))
        when (({iconv_open(3)})) failed.

--- Iconv.open(to, from)
    Equivalents to ((<Iconv.new>)) except with in the case of called
    with a block, yields with the new instance and closes it, and
    returns the result which returned from the block.
=end
*/
static VALUE
iconv_s_allocate
#ifdef HAVE_PROTOTYPES
    (VALUE klass)
#else /* HAVE_PROTOTYPES */
    (klass)
    VALUE klass;
#endif /* HAVE_PROTOTYPES */
{
    return Data_Wrap_Struct(klass, 0, ICONV_FREE, 0);
}

static VALUE
iconv_initialize
#ifdef HAVE_PROTOTYPES
    (VALUE self, VALUE to, VALUE from)
#else /* HAVE_PROTOTYPES */
    (self, to, from)
    VALUE self;
    VALUE to;
    VALUE from;
#endif /* HAVE_PROTOTYPES */
{
    iconv_free(check_iconv(self));
    DATA_PTR(self) = NULL;
    DATA_PTR(self) = (void *)ICONV2VALUE(iconv_create(to, from));
    return self;
}

static VALUE
iconv_s_open
#ifdef HAVE_PROTOTYPES
    (VALUE self, VALUE to, VALUE from)
#else /* HAVE_PROTOTYPES */
    (self, to, from)
    VALUE self;
    VALUE to;
    VALUE from;
#endif /* HAVE_PROTOTYPES */
{
    VALUE cd = ICONV2VALUE(iconv_create(to, from));

    self = Data_Wrap_Struct(self, NULL, ICONV_FREE, (void *)cd);
    if (rb_block_given_p()) {
	return rb_ensure(rb_yield, self, (VALUE(*)())iconv_finish, self);
    }
    else {
	return self;
    }
}

/*
=begin
--- Iconv.iconv(to, from, *strs)
    Shorthand for
      Iconv.open(to, from) {|cd| (strs + [nil]).collect {|s| cd.iconv(s)}}
    :Parameters
      :((|to|)), ((|from|))
        see ((<Iconv.new>)).
      :((|strs|))
        strings to be converted.
    :Exceptions
      exceptions thrown by ((<Iconv.new>)), ((<Iconv.open>)) and
      ((<Iconv#iconv>)).
=end
*/

static VALUE
iconv_s_convert
#ifdef HAVE_PROTOTYPES
    (struct iconv_env_t* env)
#else /* HAVE_PROTOTYPES */
    (env)
    struct iconv_env_t *env;
#endif /* HAVE_PROTOTYPES */
{
    VALUE last = 0;

    for (; env->argc > 0; --env->argc, ++env->argv) {
	VALUE s = iconv_convert(env->cd, last = *(env->argv), 0, -1, env);
	env->append(env->ret, s);
    }

    if (!NIL_P(last)) {
	VALUE s = iconv_convert(env->cd, Qnil, 0, 0, env);
	if (RSTRING(s)->len)
	    env->append(env->ret, s);
    }

    return env->ret;
}

static VALUE
iconv_s_iconv
#ifdef HAVE_PROTOTYPES
    (int argc, VALUE *argv, VALUE self)
#else /* HAVE_PROTOTYPES */
    (argc, argv, self)
    int argc;
    VALUE *argv;
    VALUE self;
#endif /* HAVE_PROTOTYPES */
{
    struct iconv_env_t arg;

    if (argc < 2)		/* needs `to' and `from' arguments at least */
	rb_raise(rb_eArgError, "wrong # of arguments (%d for %d)", argc, 2);

    arg.argc = argc -= 2;
    arg.argv = argv + 2;
    arg.append = rb_ary_push;
    arg.ret = rb_ary_new2(argc);
    arg.cd = iconv_create(argv[0], argv[1]);
    return rb_ensure(iconv_s_convert, (VALUE)&arg, iconv_free, ICONV2VALUE(arg.cd));
}

static VALUE
iconv_s_conv
#ifdef HAVE_PROTOTYPES
    (VALUE self, VALUE to, VALUE from, VALUE str)
#else /* HAVE_PROTOTYPES */
    (self, to, from, str)
    VALUE self, to, from, str;
#endif /* HAVE_PROTOTYPES */
{
    struct iconv_env_t arg;

    arg.argc = 1;
    arg.argv = &str;
    arg.append = rb_str_append;
    arg.ret = rb_str_new(0, 0);
    arg.cd = iconv_create(to, from);
    return rb_ensure(iconv_s_convert, (VALUE)&arg, iconv_free, ICONV2VALUE(arg.cd));
}


/*
=begin
=== Instance methods
=end
*/
/*
=begin
--- Iconv#close
    Finishes conversion.
    * After calling this, invoking method ((<Iconv#iconv>)) will cause
      exception, but multiple calls of (({close})) are guaranteed to
      end successfully.
    * Returns a string contains the byte sequence to change the
      output buffer to its initial shift state.
=end
*/
static VALUE
iconv_init_state
#ifdef HAVE_PROTOTYPES
    (VALUE cd)
#else /* HAVE_PROTOTYPES */
    (cd)
    VALUE cd;
#endif /* HAVE_PROTOTYPES */
{
    return iconv_convert(VALUE2ICONV(cd), Qnil, 0, 0, NULL);
}

static VALUE
iconv_finish
#ifdef HAVE_PROTOTYPES
    (VALUE self)
#else /* HAVE_PROTOTYPES */
    (self)
    VALUE self;
#endif /* HAVE_PROTOTYPES */
{
    VALUE cd = check_iconv(self);

    if (!cd) return Qnil;
    DATA_PTR(self) = NULL;

    return rb_ensure(iconv_init_state, cd, iconv_free, cd);
}

/*
=begin
--- Iconv#iconv(str, [ start = 0, [ length = -1 ] ])
    Converts string and returns converted one.
    * In the case of ((|str|)) is (({String})), converts (({str[start, length]})).
      Returns converted string.
    * In the case of ((|str|)) is (({nil})), places ((|converter|))
      itself into initial shift state and just returns a string contains
      the byte sequence to change the output buffer to its initial shift
      state.
    * Otherwise, causes exception.
    :Parameters
      :((|str|))
        string to be converted or (({nil})).
      :((|start|))
        starting offset.
      :((|length|))
        conversion length,
        (({nil})) or (({-1})) means whole string from (({start})).
    :Exceptions
      * ((<Iconv::IllegalSequence>))
      * ((<Iconv::InvalidCharacter>))
      * ((<Iconv::OutOfRange>))
=end
*/
static VALUE
iconv_iconv
#ifdef HAVE_PROTOTYPES
    (int argc, VALUE *argv, VALUE self)
#else /* HAVE_PROTOTYPES */
    (argc, argv, self)
    int argc;
    VALUE *argv;
    VALUE self;
#endif /* HAVE_PROTOTYPES */
{
    VALUE str, n1, n2;
    VALUE cd = check_iconv(self);

    n1 = n2 = Qnil;
    rb_scan_args(argc, argv, "12", &str, &n1, &n2);

    return iconv_convert(VALUE2ICONV(cd), str,
			 NIL_P(n1) ? 0 : NUM2INT(n1),
			 NIL_P(n2) ? -1 : NUM2INT(n1),
			 NULL);
}


/*
=begin
= Exceptions
=end
*/
/*
=begin
== Iconv::Failure
Base exceptional attributes from ((<Iconv>)).

=== Instance methods
=end
*/
/*
=begin
--- Iconv::Failure#success
    Returns string(s) translated successfully until the exception occurred.
    * In the case of failure occurred within ((<Iconv.iconv>)), returned
      value is an array of strings translated successfully preceding
      failure and the last element is string on the way.
=end
*/
static VALUE
iconv_failure_success
#ifdef HAVE_PROTOTYPES
(VALUE self)
#else /* HAVE_PROTOTYPES */
    (self)
    VALUE self;
#endif /* HAVE_PROTOTYPES */
{
    return rb_attr_get(self, rb_success);
}

/*
=begin
--- Iconv::Failure#failed
    Returns substring of the original string passed to ((<Iconv>)) that
    starts at the character caused the exception. 
=end
*/
static VALUE
iconv_failure_failed
#ifdef HAVE_PROTOTYPES
(VALUE self)
#else /* HAVE_PROTOTYPES */
    (self)
    VALUE self;
#endif /* HAVE_PROTOTYPES */
{
    return rb_attr_get(self, rb_failed);
}

/*
=begin
--- Iconv::Failure#inspect
    Returns inspected string like as: #<(({type})): "(({success}))", "(({failed}))">
=end
*/
static VALUE
iconv_failure_inspect
#ifdef HAVE_PROTOTYPES
    (VALUE self)
#else /* HAVE_PROTOTYPES */
    (self)
    VALUE self;
#endif /* HAVE_PROTOTYPES */
{
    char *cname = rb_class2name(CLASS_OF(self));
    VALUE success = rb_attr_get(self, rb_success);
    VALUE failed = rb_attr_get(self, rb_failed);
    VALUE str = rb_str_buf_cat2(rb_str_new2("#<"), cname);
    str = rb_str_buf_cat(str, ": ", 2);
    str = rb_str_buf_append(str, rb_inspect(success));
    str = rb_str_buf_cat(str, ", ", 2);
    str = rb_str_buf_append(str, rb_inspect(failed));
    return rb_str_buf_cat(str, ">", 1);
}

/*
  Hmmm, I don't like to write RD inside of function :-<.

=begin
== Iconv::IllegalSequence
Input conversion stopped due to an input byte that does not belong to
the input codeset, or the output codeset does not contain the
character.
=== Superclass
(({ArgumentError}))
=== Included Modules
((<Iconv::Failure>))

== Iconv::InvalidCharacter
Input conversion stopped due to an incomplete character or shift
sequence at the end of the input buffer.
=== Superclass
(({ArgumentError}))
=== Included Modules
((<Iconv::Failure>))

== Iconv::OutOfRange
Iconv library internal error.  Must not occur.
=== Superclass
(({RuntimeError}))
=== Included Modules
((<Iconv::Failure>))
=end
*/

void
Init_iconv _((void))
{
    VALUE rb_cIconv = rb_define_class("Iconv", rb_cData);

    rb_define_alloc_func(rb_cIconv, iconv_s_allocate);
    rb_define_singleton_method(rb_cIconv, "open", iconv_s_open, 2);
    rb_define_singleton_method(rb_cIconv, "iconv", iconv_s_iconv, -1);
    rb_define_singleton_method(rb_cIconv, "conv", iconv_s_conv, 3);
    rb_define_method(rb_cIconv, "initialize", iconv_initialize, 2);
    rb_define_method(rb_cIconv, "close", iconv_finish, 0);
    rb_define_method(rb_cIconv, "iconv", iconv_iconv, -1);

    rb_eIconvFailure = rb_define_module_under(rb_cIconv, "Failure");
    rb_define_method(rb_eIconvFailure, "initialize", iconv_failure_initialize, 3);
    rb_define_method(rb_eIconvFailure, "success", iconv_failure_success, 0);
    rb_define_method(rb_eIconvFailure, "failed", iconv_failure_failed, 0);
    rb_define_method(rb_eIconvFailure, "inspect", iconv_failure_inspect, 0);

    rb_eIconvIllegalSeq = rb_define_class_under(rb_cIconv, "IllegalSequence", rb_eArgError);
    rb_eIconvInvalidChar = rb_define_class_under(rb_cIconv, "InvalidCharacter", rb_eArgError);
    rb_eIconvOutOfRange = rb_define_class_under(rb_cIconv, "OutOfRange", rb_eRuntimeError);
    rb_include_module(rb_eIconvIllegalSeq, rb_eIconvFailure);
    rb_include_module(rb_eIconvInvalidChar, rb_eIconvFailure);
    rb_include_module(rb_eIconvOutOfRange, rb_eIconvFailure);

    rb_success = rb_intern("success");
    rb_failed = rb_intern("failed");

    charset_map = rb_hash_new();
    rb_gc_register_address(&charset_map);
    rb_define_singleton_method(rb_cIconv, "charset_map", charset_map_get, 0);
}


/*
=begin
== Example
(1) Instantiate a new ((<Iconv>)), use method ((<Iconv#iconv>)).
      cd = Iconv.new(to, from)
      begin
        input.each {|s| output << cd.iconv(s)}
        output << cd.iconv(nil)      # don't forget this
      ensure
        cd.close
      end
(2) Invoke ((<Iconv.open>)) with a block.
      Iconv.open(to, from) do |cd|
        input.each {|s| output << cd.iconv(s)}
        output << cd.iconv(nil)
      end
(3) Shorthand for (2).
      Iconv.iconv(to, from, *input.to_a)
=end
*/