1 /*	$NetBSD: utf8.c,v 1.1.1.1 2011/04/13 18:16:00 elric Exp $	*/
2 
3 /*
4  * Copyright (c) 2004, 2006, 2007, 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <config.h>
37 #include "windlocl.h"
38 
39 static int
40 utf8toutf32(const unsigned char **pp, uint32_t *out)
41 {
42     const unsigned char *p = *pp;
43     unsigned c = *p;
44 
45     if (c & 0x80) {
46 	if ((c & 0xE0) == 0xC0) {
47 	    const unsigned c2 = *++p;
48 	    if ((c2 & 0xC0) == 0x80) {
49 		*out =  ((c  & 0x1F) << 6)
50 		    | (c2 & 0x3F);
51 	    } else {
52 		return WIND_ERR_INVALID_UTF8;
53 	    }
54 	} else if ((c & 0xF0) == 0xE0) {
55 	    const unsigned c2 = *++p;
56 	    if ((c2 & 0xC0) == 0x80) {
57 		const unsigned c3 = *++p;
58 		if ((c3 & 0xC0) == 0x80) {
59 		    *out =   ((c  & 0x0F) << 12)
60 			| ((c2 & 0x3F) << 6)
61 			|  (c3 & 0x3F);
62 		} else {
63 		    return WIND_ERR_INVALID_UTF8;
64 		}
65 	    } else {
66 		return WIND_ERR_INVALID_UTF8;
67 	    }
68 	} else if ((c & 0xF8) == 0xF0) {
69 	    const unsigned c2 = *++p;
70 	    if ((c2 & 0xC0) == 0x80) {
71 		const unsigned c3 = *++p;
72 		if ((c3 & 0xC0) == 0x80) {
73 		    const unsigned c4 = *++p;
74 		    if ((c4 & 0xC0) == 0x80) {
75 			*out =   ((c  & 0x07) << 18)
76 			    | ((c2 & 0x3F) << 12)
77 			    | ((c3 & 0x3F) <<  6)
78 			    |  (c4 & 0x3F);
79 		    } else {
80 			return WIND_ERR_INVALID_UTF8;
81 		    }
82 		} else {
83 		    return WIND_ERR_INVALID_UTF8;
84 		}
85 	    } else {
86 		return WIND_ERR_INVALID_UTF8;
87 	    }
88 	} else {
89 	    return WIND_ERR_INVALID_UTF8;
90 	}
91     } else {
92 	*out = c;
93     }
94 
95     *pp = p;
96 
97     return 0;
98 }
99 
100 /**
101  * Convert an UTF-8 string to an UCS4 string.
102  *
103  * @param in an UTF-8 string to convert.
104  * @param out the resulting UCS4 strint, must be at least
105  * wind_utf8ucs4_length() long.  If out is NULL, the function will
106  * calculate the needed space for the out variable (just like
107  * wind_utf8ucs4_length()).
108  * @param out_len before processing out_len should be the length of
109  * the out variable, after processing it will be the length of the out
110  * string.
111  *
112  * @return returns 0 on success, an wind error code otherwise
113  * @ingroup wind
114  */
115 
116 int
117 wind_utf8ucs4(const char *in, uint32_t *out, size_t *out_len)
118 {
119     const unsigned char *p;
120     size_t o = 0;
121     int ret;
122 
123     for (p = (const unsigned char *)in; *p != '\0'; ++p) {
124 	uint32_t u;
125 
126 	ret = utf8toutf32(&p, &u);
127 	if (ret)
128 	    return ret;
129 
130 	if (out) {
131 	    if (o >= *out_len)
132 		return WIND_ERR_OVERRUN;
133 	    out[o] = u;
134 	}
135 	o++;
136     }
137     *out_len = o;
138     return 0;
139 }
140 
141 /**
142  * Calculate the length of from converting a UTF-8 string to a UCS4
143  * string.
144  *
145  * @param in an UTF-8 string to convert.
146  * @param out_len the length of the resulting UCS4 string.
147  *
148  * @return returns 0 on success, an wind error code otherwise
149  * @ingroup wind
150  */
151 
152 int
153 wind_utf8ucs4_length(const char *in, size_t *out_len)
154 {
155     return wind_utf8ucs4(in, NULL, out_len);
156 }
157 
158 static const char first_char[4] =
159     { 0x00, 0xC0, 0xE0, 0xF0 };
160 
161 /**
162  * Convert an UCS4 string to a UTF-8 string.
163  *
164  * @param in an UCS4 string to convert.
165  * @param in_len the length input array.
166 
167  * @param out the resulting UTF-8 strint, must be at least
168  * wind_ucs4utf8_length() + 1 long (the extra char for the NUL).  If
169  * out is NULL, the function will calculate the needed space for the
170  * out variable (just like wind_ucs4utf8_length()).
171 
172  * @param out_len before processing out_len should be the length of
173  * the out variable, after processing it will be the length of the out
174  * string.
175  *
176  * @return returns 0 on success, an wind error code otherwise
177  * @ingroup wind
178  */
179 
180 int
181 wind_ucs4utf8(const uint32_t *in, size_t in_len, char *out, size_t *out_len)
182 {
183     uint32_t ch;
184     size_t i, len, o;
185 
186     for (o = 0, i = 0; i < in_len; i++) {
187 	ch = in[i];
188 
189 	if (ch < 0x80) {
190 	    len = 1;
191 	} else if (ch < 0x800) {
192 	    len = 2;
193 	} else if (ch < 0x10000) {
194 	    len = 3;
195 	} else if (ch <= 0x10FFFF) {
196 	    len = 4;
197 	} else
198 	    return WIND_ERR_INVALID_UTF32;
199 
200 	o += len;
201 
202 	if (out) {
203 	    if (o >= *out_len)
204 		return WIND_ERR_OVERRUN;
205 
206 	    switch(len) {
207 	    case 4:
208 		out[3] = (ch | 0x80) & 0xbf;
209 		ch = ch << 6;
210 	    case 3:
211 		out[2] = (ch | 0x80) & 0xbf;
212 		ch = ch << 6;
213 	    case 2:
214 		out[1] = (ch | 0x80) & 0xbf;
215 		ch = ch << 6;
216 	    case 1:
217 		out[0] = ch | first_char[len - 1];
218 	    }
219 	}
220 	out += len;
221     }
222     if (out) {
223 	if (o + 1 >= *out_len)
224 	    return WIND_ERR_OVERRUN;
225 	*out = '\0';
226     }
227     *out_len = o;
228     return 0;
229 }
230 
231 /**
232  * Calculate the length of from converting a UCS4 string to an UTF-8 string.
233  *
234  * @param in an UCS4 string to convert.
235  * @param in_len the length of UCS4 string to convert.
236  * @param out_len the length of the resulting UTF-8 string.
237  *
238  * @return returns 0 on success, an wind error code otherwise
239  * @ingroup wind
240  */
241 
242 int
243 wind_ucs4utf8_length(const uint32_t *in, size_t in_len, size_t *out_len)
244 {
245     return wind_ucs4utf8(in, in_len, NULL, out_len);
246 }
247 
248 /**
249  * Read in an UCS2 from a buffer.
250  *
251  * @param ptr The input buffer to read from.
252  * @param len the length of the input buffer.
253  * @param flags Flags to control the behavior of the function.
254  * @param out the output UCS2, the array must be at least out/2 long.
255  * @param out_len the output length
256  *
257  * @return returns 0 on success, an wind error code otherwise.
258  * @ingroup wind
259  */
260 
261 int
262 wind_ucs2read(const void *ptr, size_t len, unsigned int *flags,
263 	      uint16_t *out, size_t *out_len)
264 {
265     const unsigned char *p = ptr;
266     int little = ((*flags) & WIND_RW_LE);
267     size_t olen = *out_len;
268 
269     /** if len is zero, flags are unchanged */
270     if (len == 0) {
271 	*out_len = 0;
272 	return 0;
273     }
274 
275     /** if len is odd, WIND_ERR_LENGTH_NOT_MOD2 is returned */
276     if (len & 1)
277 	return WIND_ERR_LENGTH_NOT_MOD2;
278 
279     /**
280      * If the flags WIND_RW_BOM is set, check for BOM. If not BOM is
281      * found, check is LE/BE flag is already and use that otherwise
282      * fail with WIND_ERR_NO_BOM. When done, clear WIND_RW_BOM and
283      * the LE/BE flag and set the resulting LE/BE flag.
284      */
285     if ((*flags) & WIND_RW_BOM) {
286 	uint16_t bom = (p[0] << 8) + p[1];
287 	if (bom == 0xfffe || bom == 0xfeff) {
288 	    little = (bom == 0xfffe);
289 	    p += 2;
290 	    len -= 2;
291 	} else if (((*flags) & (WIND_RW_LE|WIND_RW_BE)) != 0) {
292 	    /* little already set */
293 	} else
294 	    return WIND_ERR_NO_BOM;
295 	*flags = ((*flags) & ~(WIND_RW_BOM|WIND_RW_LE|WIND_RW_BE));
296 	*flags |= little ? WIND_RW_LE : WIND_RW_BE;
297     }
298 
299     while (len) {
300 	if (olen < 1)
301 	    return WIND_ERR_OVERRUN;
302 	if (little)
303 	    *out = (p[1] << 8) + p[0];
304 	else
305 	    *out = (p[0] << 8) + p[1];
306 	out++; p += 2; len -= 2; olen--;
307     }
308     *out_len -= olen;
309     return 0;
310 }
311 
312 /**
313  * Write an UCS2 string to a buffer.
314  *
315  * @param in The input UCS2 string.
316  * @param in_len the length of the input buffer.
317  * @param flags Flags to control the behavior of the function.
318  * @param ptr The input buffer to write to, the array must be at least
319  * (in + 1) * 2 bytes long.
320  * @param out_len the output length
321  *
322  * @return returns 0 on success, an wind error code otherwise.
323  * @ingroup wind
324  */
325 
326 int
327 wind_ucs2write(const uint16_t *in, size_t in_len, unsigned int *flags,
328 	       void *ptr, size_t *out_len)
329 {
330     unsigned char *p = ptr;
331     size_t len = *out_len;
332 
333     /** If in buffer is not of length be mod 2, WIND_ERR_LENGTH_NOT_MOD2 is returned*/
334     if (len & 1)
335 	return WIND_ERR_LENGTH_NOT_MOD2;
336 
337     /** On zero input length, flags are preserved */
338     if (in_len == 0) {
339 	*out_len = 0;
340 	return 0;
341     }
342     /** If flags have WIND_RW_BOM set, the byte order mark is written
343      * first to the output data */
344     if ((*flags) & WIND_RW_BOM) {
345 	uint16_t bom = 0xfffe;
346 
347 	if (len < 2)
348 	    return WIND_ERR_OVERRUN;
349 
350 	if ((*flags) & WIND_RW_LE) {
351 	    p[0] = (bom >> 8) & 0xff;
352 	    p[1] = (bom     ) & 0xff;
353 	} else {
354 	    p[1] = (bom     ) & 0xff;
355 	    p[0] = (bom >> 8) & 0xff;
356 	}
357 	len -= 2;
358     }
359 
360     while (in_len) {
361 	/** If the output wont fit into out_len, WIND_ERR_OVERRUN is returned */
362 	if (len < 2)
363 	    return WIND_ERR_OVERRUN;
364 	if ((*flags) & WIND_RW_LE) {
365 	    p[0] = (in[0] >> 8) & 0xff;
366 	    p[1] = (in[0]     ) & 0xff;
367 	} else {
368 	    p[1] = (in[0]     ) & 0xff;
369 	    p[0] = (in[0] >> 8) & 0xff;
370 	}
371 	len -= 2;
372 	in_len--;
373 	p += 2;
374 	in++;
375     }
376     *out_len -= len;
377     return 0;
378 }
379 
380 
381 /**
382  * Convert an UTF-8 string to an UCS2 string.
383  *
384  * @param in an UTF-8 string to convert.
385  * @param out the resulting UCS2 strint, must be at least
386  * wind_utf8ucs2_length() long.  If out is NULL, the function will
387  * calculate the needed space for the out variable (just like
388  * wind_utf8ucs2_length()).
389  * @param out_len before processing out_len should be the length of
390  * the out variable, after processing it will be the length of the out
391  * string.
392  *
393  * @return returns 0 on success, an wind error code otherwise
394  * @ingroup wind
395  */
396 
397 int
398 wind_utf8ucs2(const char *in, uint16_t *out, size_t *out_len)
399 {
400     const unsigned char *p;
401     size_t o = 0;
402     int ret;
403 
404     for (p = (const unsigned char *)in; *p != '\0'; ++p) {
405 	uint32_t u;
406 
407 	ret = utf8toutf32(&p, &u);
408 	if (ret)
409 	    return ret;
410 
411 	if (u & 0xffff0000)
412 	    return WIND_ERR_NOT_UTF16;
413 
414 	if (out) {
415 	    if (o >= *out_len)
416 		return WIND_ERR_OVERRUN;
417 	    out[o] = u;
418 	}
419 	o++;
420     }
421     *out_len = o;
422     return 0;
423 }
424 
425 /**
426  * Calculate the length of from converting a UTF-8 string to a UCS2
427  * string.
428  *
429  * @param in an UTF-8 string to convert.
430  * @param out_len the length of the resulting UCS4 string.
431  *
432  * @return returns 0 on success, an wind error code otherwise
433  * @ingroup wind
434  */
435 
436 int
437 wind_utf8ucs2_length(const char *in, size_t *out_len)
438 {
439     return wind_utf8ucs2(in, NULL, out_len);
440 }
441 
442 /**
443  * Convert an UCS2 string to a UTF-8 string.
444  *
445  * @param in an UCS2 string to convert.
446  * @param in_len the length of the in UCS2 string.
447  * @param out the resulting UTF-8 strint, must be at least
448  * wind_ucs2utf8_length() long.  If out is NULL, the function will
449  * calculate the needed space for the out variable (just like
450  * wind_ucs2utf8_length()).
451  * @param out_len before processing out_len should be the length of
452  * the out variable, after processing it will be the length of the out
453  * string.
454  *
455  * @return returns 0 on success, an wind error code otherwise
456  * @ingroup wind
457  */
458 
459 int
460 wind_ucs2utf8(const uint16_t *in, size_t in_len, char *out, size_t *out_len)
461 {
462     uint16_t ch;
463     size_t i, len, o;
464 
465     for (o = 0, i = 0; i < in_len; i++) {
466 	ch = in[i];
467 
468 	if (ch < 0x80) {
469 	    len = 1;
470 	} else if (ch < 0x800) {
471 	    len = 2;
472 	} else
473 	    len = 3;
474 
475 	o += len;
476 
477 	if (out) {
478 	    if (o >= *out_len)
479 		return WIND_ERR_OVERRUN;
480 
481 	    switch(len) {
482 	    case 3:
483 		out[2] = (ch | 0x80) & 0xbf;
484 		ch = ch << 6;
485 	    case 2:
486 		out[1] = (ch | 0x80) & 0xbf;
487 		ch = ch << 6;
488 	    case 1:
489 		out[0] = ch | first_char[len - 1];
490 	    }
491 	    out += len;
492 	}
493     }
494     if (out) {
495 	if (o >= *out_len)
496 	    return WIND_ERR_OVERRUN;
497 	*out = '\0';
498     }
499     *out_len = o;
500     return 0;
501 }
502 
503 /**
504  * Calculate the length of from converting a UCS2 string to an UTF-8 string.
505  *
506  * @param in an UCS2 string to convert.
507  * @param in_len an UCS2 string length to convert.
508  * @param out_len the length of the resulting UTF-8 string.
509  *
510  * @return returns 0 on success, an wind error code otherwise
511  * @ingroup wind
512  */
513 
514 int
515 wind_ucs2utf8_length(const uint16_t *in, size_t in_len, size_t *out_len)
516 {
517     return wind_ucs2utf8(in, in_len, NULL, out_len);
518 }
519