(BODY for TO_LOOP): Reject UCS-4 input in the range 0xD800..0xDFFF.
[kopensolaris-gnu/glibc.git] / iconvdata / utf-16.c
1 /* Conversion module for UTF-16.
2    Copyright (C) 1999, 2000 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
5
6    The GNU C Library is free software; you can redistribute it and/or
7    modify it under the terms of the GNU Library General Public License as
8    published by the Free Software Foundation; either version 2 of the
9    License, or (at your option) any later version.
10
11    The GNU C Library is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14    Library General Public License for more details.
15
16    You should have received a copy of the GNU Library General Public
17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19    Boston, MA 02111-1307, USA.  */
20
21 #include <byteswap.h>
22 #include <dlfcn.h>
23 #include <gconv.h>
24 #include <stddef.h>
25 #include <stdint.h>
26 #include <stdlib.h>
27 #include <string.h>
28
29 /* This is the Byte Order Mark character (BOM).  */
30 #define BOM     0xfeff
31 /* And in the other byte order.  */
32 #define BOM_OE  0xfffe
33
34
35 /* Definitions used in the body of the `gconv' function.  */
36 #define FROM_LOOP               from_utf16_loop
37 #define TO_LOOP                 to_utf16_loop
38 #define DEFINE_INIT             0
39 #define DEFINE_FINI             0
40 #define MIN_NEEDED_FROM         2
41 #define MAX_NEEDED_FROM         4
42 #define MIN_NEEDED_TO           4
43 #define FROM_DIRECTION          (dir == from_utf16)
44 #define PREPARE_LOOP \
45   enum direction dir = ((struct utf16_data *) step->__data)->dir;             \
46   enum variant var = ((struct utf16_data *) step->__data)->var;               \
47   int swap = ((struct utf16_data *) step->__data)->swap;                      \
48   if (FROM_DIRECTION || var == UTF_16)                                        \
49     {                                                                         \
50       if (data->__invocation_counter == 0)                                    \
51         {                                                                     \
52           /* We have to find out which byte order the file is encoded in.  */ \
53           if (inptr + 2 > inend)                                              \
54             return __GCONV_EMPTY_INPUT;                                       \
55                                                                               \
56           if (get16u (inptr) == BOM)                                          \
57             /* Simply ignore the BOM character.  */                           \
58             inptr += 2;                                                       \
59           else if (get16u (inptr) == BOM_OE)                                  \
60             {                                                                 \
61               ((struct utf16_data *) step->__data)->swap = 1;                 \
62               inptr += 2;                                                     \
63             }                                                                 \
64         }                                                                     \
65     }                                                                         \
66   else if (!FROM_DIRECTION && var == UTF_16 && !data->__internal_use          \
67            && data->__invocation_counter == 0)                                \
68     {                                                                         \
69       /* Emit the Byte Order Mark.  */                                        \
70       if (__builtin_expect (outbuf + 2 > outend, 0))                          \
71         return __GCONV_FULL_OUTPUT;                                           \
72                                                                               \
73       put16u (outbuf, BOM);                                                   \
74       outbuf += 2;                                                            \
75     }
76 #define EXTRA_LOOP_ARGS         , var, swap
77
78
79 /* Direction of the transformation.  */
80 enum direction
81 {
82   illegal_dir,
83   to_utf16,
84   from_utf16
85 };
86
87 enum variant
88 {
89   illegal_var,
90   UTF_16,
91   UTF_16LE,
92   UTF_16BE
93 };
94
95 struct utf16_data
96 {
97   enum direction dir;
98   enum variant var;
99   int swap;
100 };
101
102
103 int
104 gconv_init (struct __gconv_step *step)
105 {
106   /* Determine which direction.  */
107   struct utf16_data *new_data;
108   enum direction dir = illegal_dir;
109   enum variant var = illegal_var;
110   int result;
111
112   if (__strcasecmp (step->__from_name, "UTF-16//") == 0)
113     {
114       dir = from_utf16;
115       var = UTF_16;
116     }
117   else if (__strcasecmp (step->__to_name, "UTF-16//") == 0)
118     {
119       dir = to_utf16;
120       var = UTF_16;
121     }
122   else if (__strcasecmp (step->__from_name, "UTF-16BE//") == 0)
123     {
124       dir = from_utf16;
125       var = UTF_16BE;
126     }
127   else if (__strcasecmp (step->__to_name, "UTF-16BE//") == 0)
128     {
129       dir = to_utf16;
130       var = UTF_16BE;
131     }
132   else if (__strcasecmp (step->__from_name, "UTF-16LE//") == 0)
133     {
134       dir = from_utf16;
135       var = UTF_16LE;
136     }
137   else if (__strcasecmp (step->__to_name, "UTF-16LE//") == 0)
138     {
139       dir = to_utf16;
140       var = UTF_16LE;
141     }
142
143   result = __GCONV_NOCONV;
144   if (__builtin_expect (dir, to_utf16) != illegal_dir)
145     {
146       new_data = (struct utf16_data *) malloc (sizeof (struct utf16_data));
147
148       result = __GCONV_NOMEM;
149       if (new_data != NULL)
150         {
151           new_data->dir = dir;
152           new_data->var = var;
153           new_data->swap = ((var == UTF_16LE && BYTE_ORDER == BIG_ENDIAN)
154                             || (var == UTF_16BE
155                                 && BYTE_ORDER == LITTLE_ENDIAN));
156           step->__data = new_data;
157
158           if (dir == from_utf16)
159             {
160               step->__min_needed_from = MIN_NEEDED_FROM;
161               step->__max_needed_from = MIN_NEEDED_FROM;
162               step->__min_needed_to = MIN_NEEDED_TO;
163               step->__max_needed_to = MIN_NEEDED_TO;
164             }
165           else
166             {
167               step->__min_needed_from = MIN_NEEDED_TO;
168               step->__max_needed_from = MIN_NEEDED_TO;
169               step->__min_needed_to = MIN_NEEDED_FROM;
170               step->__max_needed_to = MIN_NEEDED_FROM;
171             }
172
173           step->__stateful = 0;
174
175           result = __GCONV_OK;
176         }
177     }
178
179   return result;
180 }
181
182
183 void
184 gconv_end (struct __gconv_step *data)
185 {
186   free (data->__data);
187 }
188
189
190 /* Convert from the internal (UCS4-like) format to UTF-16.  */
191 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
192 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
193 #define MAX_NEEDED_OUTPUT       MAX_NEEDED_FROM
194 #define LOOPFCT                 TO_LOOP
195 #define BODY \
196   {                                                                           \
197     uint32_t c = get32 (inptr);                                               \
198                                                                               \
199     if (__builtin_expect (c >= 0xd800 && c < 0xe000, 0))                      \
200       {                                                                       \
201         /* Surrogate characters in UCS-4 input are not valid.                 \
202            We must catch this.  If we let surrogates pass through,            \
203            attackers could make a security hole exploit by                    \
204            synthesizing any desired plane 1-16 character.  */                 \
205         if (! ignore_errors_p ())                                             \
206           {                                                                   \
207             result = __GCONV_ILLEGAL_INPUT;                                   \
208             break;                                                            \
209           }                                                                   \
210         inptr += 4;                                                           \
211         ++*irreversible;                                                      \
212         continue;                                                             \
213       }                                                                       \
214                                                                               \
215     if (swap)                                                                 \
216       {                                                                       \
217         if (__builtin_expect (c, 0) >= 0x10000)                               \
218           {                                                                   \
219             if (__builtin_expect (c, 0) >= 0x110000)                          \
220               {                                                               \
221                 STANDARD_ERR_HANDLER (4);                                     \
222               }                                                               \
223                                                                               \
224             /* Generate a surrogate character.  */                            \
225             if (__builtin_expect (outptr + 4 > outend, 0))                    \
226               {                                                               \
227                 /* Overflow in the output buffer.  */                         \
228                 result = __GCONV_FULL_OUTPUT;                                 \
229                 break;                                                        \
230               }                                                               \
231                                                                               \
232             put16 (outptr, bswap_16 (0xd7c0 + (c >> 10)));                    \
233             outptr += 2;                                                      \
234             put16 (outptr, bswap_16 (0xdc00 + (c & 0x3ff)));                  \
235           }                                                                   \
236         else                                                                  \
237           put16 (outptr, bswap_16 (c));                                       \
238       }                                                                       \
239     else                                                                      \
240       {                                                                       \
241         if (__builtin_expect (c, 0) >= 0x10000)                               \
242           {                                                                   \
243             if (__builtin_expect (c, 0) >= 0x110000)                          \
244               {                                                               \
245                 STANDARD_ERR_HANDLER (4);                                     \
246               }                                                               \
247                                                                               \
248             /* Generate a surrogate character.  */                            \
249             if (__builtin_expect (outptr + 4 > outend, 0))                    \
250               {                                                               \
251                 /* Overflow in the output buffer.  */                         \
252                 result = __GCONV_FULL_OUTPUT;                                 \
253                 break;                                                        \
254               }                                                               \
255                                                                               \
256             put16 (outptr, 0xd7c0 + (c >> 10));                               \
257             outptr += 2;                                                      \
258             put16 (outptr, 0xdc00 + (c & 0x3ff));                             \
259           }                                                                   \
260         else                                                                  \
261           put16 (outptr, c);                                                  \
262       }                                                                       \
263     outptr += 2;                                                              \
264     inptr += 4;                                                               \
265   }
266 #define LOOP_NEED_FLAGS
267 #define EXTRA_LOOP_DECLS \
268         , enum variant var, int swap
269 #include <iconv/loop.c>
270
271
272 /* Convert from UTF-16 to the internal (UCS4-like) format.  */
273 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
274 #define MAX_NEEDED_INPUT        MAX_NEEDED_FROM
275 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
276 #define LOOPFCT                 FROM_LOOP
277 #define BODY \
278   {                                                                           \
279     uint16_t u1 = get16 (inptr);                                              \
280                                                                               \
281     if (swap)                                                                 \
282       {                                                                       \
283         u1 = bswap_16 (u1);                                                   \
284                                                                               \
285         if (__builtin_expect (u1, 0) < 0xd800 || u1 > 0xdfff)                 \
286           {                                                                   \
287             /* No surrogate.  */                                              \
288             put32 (outptr, u1);                                               \
289             inptr += 2;                                                       \
290           }                                                                   \
291         else                                                                  \
292           {                                                                   \
293             uint16_t u2;                                                      \
294                                                                               \
295             /* It's a surrogate character.  At least the first word says      \
296                it is.  */                                                     \
297             if (__builtin_expect (inptr + 4 > inend, 0))                      \
298               {                                                               \
299                 /* We don't have enough input for another complete input      \
300                    character.  */                                             \
301                 result = __GCONV_INCOMPLETE_INPUT;                            \
302                 break;                                                        \
303               }                                                               \
304                                                                               \
305             inptr += 2;                                                       \
306             u2 = bswap_16 (get16 (inptr));                                    \
307             if (__builtin_expect (u2, 0xdc00) < 0xdc00                        \
308                 || __builtin_expect (u2, 0xdc00) >= 0xdfff)                   \
309               {                                                               \
310                 /* This is no valid second word for a surrogate.  */          \
311                 if (! ignore_errors_p ())                                     \
312                   {                                                           \
313                     inptr -= 2;                                               \
314                     result = __GCONV_ILLEGAL_INPUT;                           \
315                     break;                                                    \
316                   }                                                           \
317                                                                               \
318                 ++*irreversible;                                              \
319                 continue;                                                     \
320               }                                                               \
321                                                                               \
322             put32 (outptr, ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00));            \
323             inptr += 2;                                                       \
324           }                                                                   \
325       }                                                                       \
326     else                                                                      \
327       {                                                                       \
328         if (__builtin_expect (u1, 0) < 0xd800 || u1 > 0xdfff)                 \
329           {                                                                   \
330             /* No surrogate.  */                                              \
331             put32 (outptr, u1);                                               \
332             inptr += 2;                                                       \
333           }                                                                   \
334         else                                                                  \
335           {                                                                   \
336             uint16_t u2;                                                      \
337                                                                               \
338             /* It's a surrogate character.  At least the first word says      \
339                it is.  */                                                     \
340             if (__builtin_expect (inptr + 4 > inend, 0))                      \
341               {                                                               \
342                 /* We don't have enough input for another complete input      \
343                    character.  */                                             \
344                 result = __GCONV_INCOMPLETE_INPUT;                            \
345                 break;                                                        \
346               }                                                               \
347                                                                               \
348             inptr += 2;                                                       \
349             u2 = get16 (inptr);                                               \
350             if (__builtin_expect (u2, 0xdc00) < 0xdc00                        \
351                 || __builtin_expect (u2, 0xdc00) >= 0xdfff)                   \
352               {                                                               \
353                 /* This is no valid second word for a surrogate.  */          \
354                 if (! ignore_errors_p ())                                     \
355                   {                                                           \
356                     inptr -= 2;                                               \
357                     result = __GCONV_ILLEGAL_INPUT;                           \
358                     break;                                                    \
359                   }                                                           \
360                                                                               \
361                 ++*irreversible;                                              \
362                 continue;                                                     \
363               }                                                               \
364                                                                               \
365             put32 (outptr, ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00));            \
366             inptr += 2;                                                       \
367           }                                                                   \
368       }                                                                       \
369     outptr += 4;                                                              \
370   }
371 #define LOOP_NEED_FLAGS
372 #define EXTRA_LOOP_DECLS \
373         , enum variant var, int swap
374 #include <iconv/loop.c>
375
376
377 /* Now define the toplevel functions.  */
378 #include <iconv/skeleton.c>