1#include <iconv.h>
2#include <errno.h>
3#include <wchar.h>
4#include <string.h>
5#include <stdlib.h>
6#include <limits.h>
7#include <stdint.h>
8
9#define UTF_32BE    0300
10#define UTF_16LE    0301
11#define UTF_16BE    0302
12#define UTF_32LE    0303
13#define UCS2BE      0304
14#define UCS2LE      0305
15#define WCHAR_T     0306
16#define US_ASCII    0307
17#define UTF_8       0310
18#define EUC_JP      0320
19#define SHIFT_JIS   0321
20#define GB18030     0330
21#define GBK         0331
22#define GB2312      0332
23#define BIG5        0340
24#define EUC_KR      0350
25
26/* FIXME: these are not implemented yet
27 * EUC:   A1-FE A1-FE
28 * GBK:   81-FE 40-7E,80-FE
29 * Big5:  A1-FE 40-7E,A1-FE
30 */
31
32/* Definitions of charmaps. Each charmap consists of:
33 * 1. Empty-string-terminated list of null-terminated aliases.
34 * 2. Special type code or number of elided entries.
35 * 3. Character table (size determined by field 2). */
36
37static const unsigned char charmaps[] =
38"utf8\0\0\310"
39"wchart\0\0\306"
40"ucs2\0ucs2be\0\0\304"
41"ucs2le\0\0\305"
42"utf16\0utf16be\0\0\302"
43"utf16le\0\0\301"
44"ucs4\0ucs4be\0utf32\0utf32be\0\0\300"
45"ucs4le\0utf32le\0\0\303"
46"ascii\0usascii\0iso646\0iso646us\0\0\307"
47"eucjp\0\0\320"
48"shiftjis\0sjis\0\0\321"
49"gb18030\0\0\330"
50"gbk\0\0\331"
51"gb2312\0\0\332"
52"big5\0bigfive\0cp950\0big5hkscs\0\0\340"
53"euckr\0ksc5601\0ksx1001\0cp949\0\0\350"
54#include "codepages.h"
55;
56
57static const unsigned short legacy_chars[] = {
58#include "legacychars.h"
59};
60
61static const unsigned short jis0208[84][94] = {
62#include "jis0208.h"
63};
64
65static const unsigned short gb18030[126][190] = {
66#include "gb18030.h"
67};
68
69static const unsigned short big5[89][157] = {
70#include "big5.h"
71};
72
73static const unsigned short hkscs[] = {
74#include "hkscs.h"
75};
76
77static const unsigned short ksc[93][94] = {
78#include "ksc.h"
79};
80
81static int fuzzycmp(const unsigned char *a, const unsigned char *b)
82{
83	for (; *a && *b; a++, b++) {
84		while (*a && (*a|32U)-'a'>26 && *a-'0'>10U) a++;
85		if ((*a|32U) != *b) return 1;
86	}
87	return *a != *b;
88}
89
90static size_t find_charmap(const void *name)
91{
92	const unsigned char *s;
93	for (s=charmaps; *s; ) {
94		if (!fuzzycmp(name, s)) {
95			for (; *s; s+=strlen((void *)s)+1);
96			return s+1-charmaps;
97		}
98		s += strlen((void *)s)+1;
99		if (!*s) {
100			if (s[1] > 0200) s+=2;
101			else s+=2+(128U-s[1])/4*5;
102		}
103	}
104	return -1;
105}
106
107iconv_t iconv_open(const char *to, const char *from)
108{
109	size_t f, t;
110
111	if ((t = find_charmap(to))==-1
112	 || (f = find_charmap(from))==-1
113	 || (charmaps[t] >= 0320)) {
114		errno = EINVAL;
115		return (iconv_t)-1;
116	}
117
118	return (void *)(f<<16 | t);
119}
120
121int iconv_close(iconv_t cd)
122{
123	return 0;
124}
125
126static unsigned get_16(const unsigned char *s, int e)
127{
128	e &= 1;
129	return s[e]<<8 | s[1-e];
130}
131
132static void put_16(unsigned char *s, unsigned c, int e)
133{
134	e &= 1;
135	s[e] = c>>8;
136	s[1-e] = c;
137}
138
139static unsigned get_32(const unsigned char *s, int e)
140{
141	e &= 3;
142	return s[e]+0U<<24 | s[e^1]<<16 | s[e^2]<<8 | s[e^3];
143}
144
145static void put_32(unsigned char *s, unsigned c, int e)
146{
147	e &= 3;
148	s[e^0] = c>>24;
149	s[e^1] = c>>16;
150	s[e^2] = c>>8;
151	s[e^3] = c;
152}
153
154/* Adapt as needed */
155#define mbrtowc_utf8 mbrtowc
156#define wctomb_utf8 wctomb
157
158size_t iconv(iconv_t cd0, char **restrict in, size_t *restrict inb, char **restrict out, size_t *restrict outb)
159{
160	size_t x=0;
161	unsigned long cd = (unsigned long)cd0;
162	unsigned to = cd & 0xffff;
163	unsigned from = cd >> 16;
164	const unsigned char *map = charmaps+from+1;
165	const unsigned char *tomap = charmaps+to+1;
166	mbstate_t st = {0};
167	wchar_t wc;
168	unsigned c, d;
169	size_t k, l;
170	int err;
171	unsigned char type = map[-1];
172	unsigned char totype = tomap[-1];
173
174	if (!in || !*in || !*inb) return 0;
175
176	for (; *inb; *in+=l, *inb-=l) {
177		c = *(unsigned char *)*in;
178		l = 1;
179
180		if (c >= 128 || type-UTF_32BE < 7U) switch (type) {
181		case UTF_8:
182			l = mbrtowc_utf8(&wc, *in, *inb, &st);
183			if (!l) l++;
184			else if (l == (size_t)-1) goto ilseq;
185			else if (l == (size_t)-2) goto starved;
186			c = wc;
187			break;
188		case US_ASCII:
189			goto ilseq;
190		case WCHAR_T:
191			l = sizeof(wchar_t);
192			if (*inb < l) goto starved;
193			c = *(wchar_t *)*in;
194			if (0) {
195		case UTF_32BE:
196		case UTF_32LE:
197			l = 4;
198			if (*inb < 4) goto starved;
199			c = get_32((void *)*in, type);
200			}
201			if (c-0xd800u < 0x800u || c >= 0x110000u) goto ilseq;
202			break;
203		case UCS2BE:
204		case UCS2LE:
205		case UTF_16BE:
206		case UTF_16LE:
207			l = 2;
208			if (*inb < 2) goto starved;
209			c = get_16((void *)*in, type);
210			if ((unsigned)(c-0xdc00) < 0x400) goto ilseq;
211			if ((unsigned)(c-0xd800) < 0x400) {
212				if (type-UCS2BE < 2U) goto ilseq;
213				l = 4;
214				if (*inb < 4) goto starved;
215				d = get_16((void *)(*in + 2), type);
216				if ((unsigned)(d-0xdc00) >= 0x400) goto ilseq;
217				c = ((c-0xd7c0)<<10) + (d-0xdc00);
218			}
219			break;
220		case SHIFT_JIS:
221			if (c-0xa1 <= 0xdf-0xa1) {
222				c += 0xff61-0xa1;
223				break;
224			}
225			l = 2;
226			if (*inb < 2) goto starved;
227			d = *((unsigned char *)*in + 1);
228			if (c-129 <= 159-129) c -= 129;
229			else if (c-224 <= 239-224) c -= 193;
230			else goto ilseq;
231			c *= 2;
232			if (d-64 <= 158-64) {
233				if (d==127) goto ilseq;
234				if (d>127) d--;
235				d -= 64;
236			} else if (d-159 <= 252-159) {
237				c++;
238				d -= 159;
239			}
240			c = jis0208[c][d];
241			if (!c) goto ilseq;
242			break;
243		case EUC_JP:
244			l = 2;
245			if (*inb < 2) goto starved;
246			d = *((unsigned char *)*in + 1);
247			if (c==0x8e) {
248				c = d;
249				if (c-0xa1 > 0xdf-0xa1) goto ilseq;
250				c += 0xff61 - 0xa1;
251				break;
252			}
253			c -= 0xa1;
254			d -= 0xa1;
255			if (c >= 84 || d >= 94) goto ilseq;
256			c = jis0208[c][d];
257			if (!c) goto ilseq;
258			break;
259		case GB2312:
260			if (c < 0xa1) goto ilseq;
261		case GBK:
262		case GB18030:
263			c -= 0x81;
264			if (c >= 126) goto ilseq;
265			l = 2;
266			if (*inb < 2) goto starved;
267			d = *((unsigned char *)*in + 1);
268			if (d < 0xa1 && type == GB2312) goto ilseq;
269			if (d-0x40>=191 || d==127) {
270				if (d-'0'>9 || type != GB18030)
271					goto ilseq;
272				l = 4;
273				if (*inb < 4) goto starved;
274				c = (10*c + d-'0') * 1260;
275				d = *((unsigned char *)*in + 2);
276				if (d-0x81>126) goto ilseq;
277				c += 10*(d-0x81);
278				d = *((unsigned char *)*in + 3);
279				if (d-'0'>9) goto ilseq;
280				c += d-'0';
281				c += 128;
282				for (d=0; d<=c; ) {
283					k = 0;
284                                       int i, j;
285					for (i=0; i<126; i++)
286						for (j=0; j<190; j++)
287							if (gb18030[i][j]-d <= c-d)
288								k++;
289					d = c+1;
290					c += k;
291				}
292				break;
293			}
294			d -= 0x40;
295			if (d>63) d--;
296			c = gb18030[c][d];
297			break;
298		case BIG5:
299			l = 2;
300			if (*inb < 2) goto starved;
301			d = *((unsigned char *)*in + 1);
302			if (d-0x40>=0xff-0x40 || d-0x7f<0xa1-0x7f) goto ilseq;
303			d -= 0x40;
304			if (d > 0x3e) d -= 0x22;
305			if (c-0xa1>=0xfa-0xa1) {
306				if (c-0x87>=0xff-0x87) goto ilseq;
307				if (c < 0xa1) c -= 0x87;
308				else c -= 0x87 + (0xfa-0xa1);
309				c = (hkscs[4867+(c*157+d)/16]>>(c*157+d)%16)%2<<17
310					| hkscs[c*157+d];
311				/* A few HKSCS characters map to pairs of UCS
312				 * characters. These are mapped to surrogate
313				 * range in the hkscs table then hard-coded
314				 * here. Ugly, yes. */
315				if (c/256 == 0xdc) {
316					if (totype-0300U > 8) k = 2;
317					else k = "\10\4\4\10\4\4\10\2\4"[totype-0300];
318					if (k > *outb) goto toobig;
319					x += iconv((iconv_t)(uintptr_t)to,
320						&(char *){"\303\212\314\204"
321						"\303\212\314\214"
322						"\303\252\314\204"
323						"\303\252\314\214"
324						+c%256}, &(size_t){4},
325						out, outb);
326					continue;
327				}
328				if (!c) goto ilseq;
329				break;
330			}
331			c -= 0xa1;
332			c = big5[c][d]|(c==0x27&&(d==0x3a||d==0x3c||d==0x42))<<17;
333			if (!c) goto ilseq;
334			break;
335		case EUC_KR:
336			l = 2;
337			if (*inb < 2) goto starved;
338			d = *((unsigned char *)*in + 1);
339			c -= 0xa1;
340			d -= 0xa1;
341			if (c >= 93 || d >= 94) {
342				c += (0xa1-0x81);
343				d += 0xa1;
344				if (c >= 93 || c>=0xc6-0x81 && d>0x52)
345					goto ilseq;
346				if (d-'A'<26) d = d-'A';
347				else if (d-'a'<26) d = d-'a'+26;
348				else if (d-0x81<0xff-0x81) d = d-0x81+52;
349				else goto ilseq;
350				if (c < 0x20) c = 178*c + d;
351				else c = 178*0x20 + 84*(c-0x20) + d;
352				c += 0xac00;
353				for (d=0xac00; d<=c; ) {
354					k = 0;
355                                       int i, j;
356					for (i=0; i<93; i++)
357						for (j=0; j<94; j++)
358							if (ksc[i][j]-d <= c-d)
359								k++;
360					d = c+1;
361					c += k;
362				}
363				break;
364			}
365			c = ksc[c][d];
366			if (!c) goto ilseq;
367			break;
368		default:
369			if (c < 128+type) break;
370			c -= 128+type;
371			c = legacy_chars[ map[c*5/4]>>2*c%8 |
372				map[c*5/4+1]<<8-2*c%8 & 1023 ];
373			if (!c) c = *(unsigned char *)*in;
374			if (c==1) goto ilseq;
375		}
376
377		switch (totype) {
378		case WCHAR_T:
379			if (*outb < sizeof(wchar_t)) goto toobig;
380			*(wchar_t *)*out = c;
381			*out += sizeof(wchar_t);
382			*outb -= sizeof(wchar_t);
383			break;
384		case UTF_8:
385			if (*outb < 4) {
386				char tmp[4];
387				k = wctomb_utf8(tmp, c);
388				if (*outb < k) goto toobig;
389				memcpy(*out, tmp, k);
390			} else k = wctomb_utf8(*out, c);
391			*out += k;
392			*outb -= k;
393			break;
394		case US_ASCII:
395			if (c > 0x7f) subst: x++, c='*';
396		default:
397			if (*outb < 1) goto toobig;
398			if (c < 128+totype) {
399			revout:
400				*(*out)++ = c;
401				*outb -= 1;
402				break;
403			}
404			d = c;
405			for (c=0; c<128-totype; c++) {
406				if (d == legacy_chars[ tomap[c*5/4]>>2*c%8 |
407					tomap[c*5/4+1]<<8-2*c%8 & 1023 ]) {
408					c += 128;
409					goto revout;
410				}
411			}
412			goto subst;
413		case UCS2BE:
414		case UCS2LE:
415		case UTF_16BE:
416		case UTF_16LE:
417			if (c < 0x10000 || type-UCS2BE < 2U) {
418				if (c >= 0x10000) c = 0xFFFD;
419				if (*outb < 2) goto toobig;
420				put_16((void *)*out, c, totype);
421				*out += 2;
422				*outb -= 2;
423				break;
424			}
425			if (*outb < 4) goto toobig;
426			c -= 0x10000;
427			put_16((void *)*out, (c>>10)|0xd800, totype);
428			put_16((void *)(*out + 2), (c&0x3ff)|0xdc00, totype);
429			*out += 4;
430			*outb -= 4;
431			break;
432		case UTF_32BE:
433		case UTF_32LE:
434			if (*outb < 4) goto toobig;
435			put_32((void *)*out, c, totype);
436			*out += 4;
437			*outb -= 4;
438			break;
439		}
440	}
441	return x;
442ilseq:
443	err = EILSEQ;
444	x = -1;
445	goto end;
446toobig:
447	err = E2BIG;
448	x = -1;
449	goto end;
450starved:
451	err = EINVAL;
452	x = -1;
453end:
454	errno = err;
455	return x;
456}
457