1 /* Conversion loop frame work.
2 Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
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.
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.
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. */
21 /* This file provides a frame for the reader loop in all conversion modules.
22 The actual code must (of course) be provided in the actual module source
23 code but certain actions can be written down generically, with some
24 customization options which are these:
26 MIN_NEEDED_INPUT minimal number of input bytes needed for the next
28 MIN_NEEDED_OUTPUT minimal number of bytes produced by the next round
31 MAX_NEEDED_INPUT you guess it, this is the maximal number of input
32 bytes needed. It defaults to MIN_NEEDED_INPUT
33 MAX_NEEDED_OUTPUT likewise for output bytes.
35 LOOPFCT name of the function created. If not specified
36 the name is `loop' but this prevents the use
37 of multiple functions in the same file.
39 BODY this is supposed to expand to the body of the loop.
40 The user must provide this.
42 EXTRA_LOOP_DECLS extra arguments passed from converion loop call.
44 INIT_PARAMS code to define and initialize variables from params.
45 UPDATE_PARAMS code to store result in params.
54 #include <sys/param.h> /* For MIN. */
59 /* We have to provide support for machines which are not able to handled
60 unaligned memory accesses. Some of the character encodings have
61 representations with a fixed width of 2 or 4 bytes. But if we cannot
62 access unaligned memory we still have to read byte-wise. */
64 #if defined _STRING_ARCH_unaligned || !defined DEFINE_UNALIGNED
65 /* We can handle unaligned memory access. */
66 # define get16(addr) *((uint16_t *) (addr))
67 # define get32(addr) *((uint32_t *) (addr))
69 /* We need no special support for writing values either. */
70 # define put16(addr, val) *((uint16_t *) (addr)) = (val)
71 # define put32(addr, val) *((uint32_t *) (addr)) = (val)
73 # define FCTNAME2(name) name
75 /* Distinguish between big endian and little endian. */
76 # if __BYTE_ORDER == __LITTLE_ENDIAN
77 # define get16(addr) \
78 (((__const unsigned char *) (addr))[1] << 8 \
79 | ((__const unsigned char *) (addr))[0])
80 # define get32(addr) \
81 (((((__const unsigned char *) (addr))[3] << 8 \
82 | ((__const unsigned char *) (addr))[2]) << 8 \
83 | ((__const unsigned char *) (addr))[1]) << 8 \
84 | ((__const unsigned char *) (addr))[0])
86 # define put16(addr, val) \
87 ({ uint16_t __val = (val); \
88 ((unsigned char *) (addr))[0] = __val; \
89 ((unsigned char *) (addr))[1] = __val >> 8; \
91 # define put32(addr, val) \
92 ({ uint32_t __val = (val); \
93 ((unsigned char *) (addr))[0] = __val; \
95 ((unsigned char *) (addr))[1] = __val; \
97 ((unsigned char *) (addr))[2] = __val; \
99 ((unsigned char *) (addr))[3] = __val; \
102 # define get16(addr) \
103 (((__const unsigned char *) (addr))[0] << 8 \
104 | ((__const unsigned char *) (addr))[1])
105 # define get32(addr) \
106 (((((__const unsigned char *) (addr))[0] << 8 \
107 | ((__const unsigned char *) (addr))[1]) << 8 \
108 | ((__const unsigned char *) (addr))[2]) << 8 \
109 | ((__const unsigned char *) (addr))[3])
111 # define put16(addr, val) \
112 ({ uint16_t __val = (val); \
113 ((unsigned char *) (addr))[1] = __val; \
114 ((unsigned char *) (addr))[2] = __val >> 8; \
116 # define put32(addr, val) \
117 ({ uint32_t __val = (val); \
118 ((unsigned char *) (addr))[3] = __val; \
120 ((unsigned char *) (addr))[2] = __val; \
122 ((unsigned char *) (addr))[1] = __val; \
124 ((unsigned char *) (addr))[0] = __val; \
128 # define FCTNAME2(name) name##_unaligned
130 #define FCTNAME(name) FCTNAME2(name)
133 /* We need at least one byte for the next round. */
134 #ifndef MIN_NEEDED_INPUT
135 # error "MIN_NEEDED_INPUT definition missing"
138 /* Let's see how many bytes we produce. */
139 #ifndef MAX_NEEDED_INPUT
140 # define MAX_NEEDED_INPUT MIN_NEEDED_INPUT
143 /* We produce at least one byte in the next round. */
144 #ifndef MIN_NEEDED_OUTPUT
145 # error "MIN_NEEDED_OUTPUT definition missing"
148 /* Let's see how many bytes we produce. */
149 #ifndef MAX_NEEDED_OUTPUT
150 # define MAX_NEEDED_OUTPUT MIN_NEEDED_OUTPUT
153 /* Default name for the function. */
155 # define LOOPFCT loop
158 /* Make sure we have a loop body. */
160 # error "Definition of BODY missing for function" LOOPFCT
164 /* If no arguments have to passed to the loop function define the macro
166 #ifndef EXTRA_LOOP_DECLS
167 # define EXTRA_LOOP_DECLS
171 /* To make it easier for the writers of the modules, we define a macro
172 to test whether we have to ignore errors. */
173 #define ignore_errors_p() \
174 (irreversible != NULL && (flags & __GCONV_IGNORE_ERRORS))
177 /* Error handling with transliteration/transcription function use and
178 ignoring of errors. Note that we cannot use the do while (0) trick
179 since `break' and `continue' must reach certain points. */
180 #define STANDARD_ERR_HANDLER(Incr) \
182 struct __gconv_trans_data *trans; \
184 result = __GCONV_ILLEGAL_INPUT; \
186 if (irreversible == NULL) \
187 /* This means we are in call from __gconv_transliterate. In this \
188 case we are not doing any error recovery outself. */ \
191 /* First try the transliteration methods. */ \
192 for (trans = step_data->__trans; trans != NULL; trans = trans->__next) \
194 result = DL_CALL_FCT (trans->__trans_fct, \
195 (step, step_data, trans->__data, *inptrp, \
196 &inptr, inend, &outptr, irreversible)); \
197 if (result != __GCONV_ILLEGAL_INPUT) \
200 /* If any of them recognized the input continue with the loop. */ \
201 if (result != __GCONV_ILLEGAL_INPUT) \
204 /* Next see whether we have to ignore the error. If not, stop. */ \
205 if (! ignore_errors_p ()) \
208 /* When we come here it means we ignore the character. */ \
215 /* The function returns the status, as defined in gconv.h. */
217 FCTNAME (LOOPFCT
) (struct __gconv_step
*step
,
218 struct __gconv_step_data
*step_data
,
219 const unsigned char **inptrp
, const unsigned char *inend
,
220 unsigned char **outptrp
, unsigned char *outend
,
221 size_t *irreversible EXTRA_LOOP_DECLS
)
223 #ifdef LOOP_NEED_STATE
224 mbstate_t *state
= step_data
->__statep
;
226 #ifdef LOOP_NEED_FLAGS
227 int flags
= step_data
->__flags
;
229 #ifdef LOOP_NEED_DATA
230 void *data
= step
->__data
;
232 int result
= __GCONV_EMPTY_INPUT
;
233 const unsigned char *inptr
= *inptrp
;
234 unsigned char *outptr
= *outptrp
;
240 while (inptr
!= inend
)
242 /* `if' cases for MIN_NEEDED_OUTPUT ==/!= 1 is made to help the
243 compiler generating better code. They will be optimized away
244 since MIN_NEEDED_OUTPUT is always a constant. */
245 if ((MIN_NEEDED_OUTPUT
!= 1
246 && __builtin_expect (outptr
+ MIN_NEEDED_OUTPUT
> outend
, 0))
247 || (MIN_NEEDED_OUTPUT
== 1
248 && __builtin_expect (outptr
>= outend
, 0)))
250 /* Overflow in the output buffer. */
251 result
= __GCONV_FULL_OUTPUT
;
254 if (MIN_NEEDED_INPUT
> 1
255 && __builtin_expect (inptr
+ MIN_NEEDED_INPUT
> inend
, 0))
257 /* We don't have enough input for another complete input
259 result
= __GCONV_INCOMPLETE_INPUT
;
263 /* Here comes the body the user provides. It can stop with
264 RESULT set to GCONV_INCOMPLETE_INPUT (if the size of the
265 input characters vary in size), GCONV_ILLEGAL_INPUT, or
266 GCONV_FULL_OUTPUT (if the output characters vary in size). */
270 /* Update the pointers pointed to by the parameters. */
281 /* Include the file a second time to define the function to handle
283 #if !defined DEFINE_UNALIGNED && !defined _STRING_ARCH_unaligned \
284 && MIN_NEEDED_FROM != 1 && MAX_NEEDED_FROM % MIN_NEEDED_FROM == 0 \
285 && MIN_NEEDED_TO != 1 && MAX_NEEDED_TO % MIN_NEEDED_TO == 0
292 # define DEFINE_UNALIGNED
294 # undef DEFINE_UNALIGNED
298 #if MAX_NEEDED_INPUT > 1
299 # define SINGLE(fct) SINGLE2 (fct)
300 # define SINGLE2(fct) fct##_single
302 SINGLE(LOOPFCT
) (struct __gconv_step
*step
,
303 struct __gconv_step_data
*step_data
,
304 const unsigned char **inptrp
, const unsigned char *inend
,
305 unsigned char **outptrp
, unsigned char *outend
,
306 size_t *irreversible EXTRA_LOOP_DECLS
)
308 mbstate_t *state
= step_data
->__statep
;
309 #ifdef LOOP_NEED_FLAGS
310 int flags
= step_data
->__flags
;
312 #ifdef LOOP_NEED_DATA
313 void *data
= step
->__data
;
315 int result
= __GCONV_OK
;
316 unsigned char bytebuf
[MAX_NEEDED_INPUT
];
317 const unsigned char *inptr
= *inptrp
;
318 unsigned char *outptr
= *outptrp
;
328 /* Add the bytes from the state to the input buffer. */
329 for (inlen
= 0; inlen
< (state
->__count
& 7); ++ inlen
)
330 bytebuf
[inlen
] = state
->__value
.__wchb
[inlen
];
333 /* Are there enough bytes in the input buffer? */
334 if (__builtin_expect (inptr
+ (MIN_NEEDED_INPUT
- inlen
) > inend
, 0))
340 inend
= &bytebuf
[inlen
];
344 /* We don't have enough input for another complete input
346 while (inptr
< inend
)
347 state
->__value
.__wchb
[inlen
++] = *inptr
++;
350 return __GCONV_INCOMPLETE_INPUT
;
353 /* Enough space in output buffer. */
354 if ((MIN_NEEDED_OUTPUT
!= 1 && outptr
+ MIN_NEEDED_OUTPUT
> outend
)
355 || (MIN_NEEDED_OUTPUT
== 1 && outptr
>= outend
))
356 /* Overflow in the output buffer. */
357 return __GCONV_FULL_OUTPUT
;
359 /* Now add characters from the normal input buffer. */
361 bytebuf
[inlen
++] = *inptr
++;
362 while (inlen
< MAX_NEEDED_INPUT
&& inptr
< inend
);
365 inend
= &bytebuf
[inlen
];
373 /* Now we either have produced an output character and consumed all the
374 bytes from the state and at least one more, or the character is still
375 incomplete, or we have some other error (like illegal input character,
376 no space in output buffer). */
377 if (__builtin_expect (inptr
!= bytebuf
, 1))
379 /* We found a new character. */
380 assert (inptr
- bytebuf
> (state
->__count
& 7));
382 *inptrp
+= inptr
- bytebuf
- (state
->__count
& 7);
387 /* Clear the state buffer. */
388 state
->__count
&= ~7;
390 else if (result
== __GCONV_INCOMPLETE_INPUT
)
392 /* This can only happen if we have less than MAX_NEEDED_INPUT bytes
394 assert (inend
!= &bytebuf
[MAX_NEEDED_INPUT
]);
396 *inptrp
+= inend
- bytebuf
- (state
->__count
& 7);
402 /* We don't have enough input for another complete input
404 while (inptr
< inend
)
405 state
->__value
.__wchb
[inlen
++] = *inptr
++;
416 /* We remove the macro definitions so that we can include this file again
417 for the definition of another function. */
418 #undef MIN_NEEDED_INPUT
419 #undef MAX_NEEDED_INPUT
420 #undef MIN_NEEDED_OUTPUT
421 #undef MAX_NEEDED_OUTPUT
425 #undef EXTRA_LOOP_DECLS
429 #undef LOOP_NEED_STATE
430 #undef LOOP_NEED_FLAGS
431 #undef LOOP_NEED_DATA