1 /*
2  * cjkcodecs.h: common header for cjkcodecs
3  *
4  * Written by Hye-Shik Chang <perky@FreeBSD.org>
5  */
6 
7 #ifndef _CJKCODECS_H_
8 #define _CJKCODECS_H_
9 
10 #define PY_SSIZE_T_CLEAN
11 #include "Python.h"
12 #include "multibytecodec.h"
13 
14 
15 /* a unicode "undefined" code point */
16 #define UNIINV  0xFFFE
17 
18 /* internal-use DBCS code points which aren't used by any charsets */
19 #define NOCHAR  0xFFFF
20 #define MULTIC  0xFFFE
21 #define DBCINV  0xFFFD
22 
23 /* shorter macros to save source size of mapping tables */
24 #define U UNIINV
25 #define N NOCHAR
26 #define M MULTIC
27 #define D DBCINV
28 
29 struct dbcs_index {
30     const ucs2_t *map;
31     unsigned char bottom, top;
32 };
33 typedef struct dbcs_index decode_map;
34 
35 struct widedbcs_index {
36     const Py_UCS4 *map;
37     unsigned char bottom, top;
38 };
39 typedef struct widedbcs_index widedecode_map;
40 
41 struct unim_index {
42     const DBCHAR *map;
43     unsigned char bottom, top;
44 };
45 typedef struct unim_index encode_map;
46 
47 struct unim_index_bytebased {
48     const unsigned char *map;
49     unsigned char bottom, top;
50 };
51 
52 struct dbcs_map {
53     const char *charset;
54     const struct unim_index *encmap;
55     const struct dbcs_index *decmap;
56 };
57 
58 struct pair_encodemap {
59     Py_UCS4 uniseq;
60     DBCHAR code;
61 };
62 
63 static const MultibyteCodec *codec_list;
64 static const struct dbcs_map *mapping_list;
65 
66 #define CODEC_INIT(encoding)                                            \
67     static int encoding##_codec_init(const void *config)
68 
69 #define ENCODER_INIT(encoding)                                          \
70     static int encoding##_encode_init(                                  \
71         MultibyteCodec_State *state, const void *config)
72 #define ENCODER(encoding)                                               \
73     static Py_ssize_t encoding##_encode(                                \
74         MultibyteCodec_State *state, const void *config,                \
75         int kind, void *data,                          \
76         Py_ssize_t *inpos, Py_ssize_t inlen,                            \
77         unsigned char **outbuf, Py_ssize_t outleft, int flags)
78 #define ENCODER_RESET(encoding)                                         \
79     static Py_ssize_t encoding##_encode_reset(                          \
80         MultibyteCodec_State *state, const void *config,                \
81         unsigned char **outbuf, Py_ssize_t outleft)
82 
83 #define DECODER_INIT(encoding)                                          \
84     static int encoding##_decode_init(                                  \
85         MultibyteCodec_State *state, const void *config)
86 #define DECODER(encoding)                                               \
87     static Py_ssize_t encoding##_decode(                                \
88         MultibyteCodec_State *state, const void *config,                \
89         const unsigned char **inbuf, Py_ssize_t inleft,                 \
90         _PyUnicodeWriter *writer)
91 #define DECODER_RESET(encoding)                                         \
92     static Py_ssize_t encoding##_decode_reset(                          \
93         MultibyteCodec_State *state, const void *config)
94 
95 #define NEXT_IN(i)                              \
96     do {                                        \
97         (*inbuf) += (i);                        \
98         (inleft) -= (i);                        \
99     } while (0)
100 #define NEXT_INCHAR(i)                          \
101     do {                                        \
102         (*inpos) += (i);                        \
103     } while (0)
104 #define NEXT_OUT(o)                             \
105     do {                                        \
106         (*outbuf) += (o);                       \
107         (outleft) -= (o);                       \
108     } while (0)
109 #define NEXT(i, o)                              \
110     do {                                        \
111         NEXT_INCHAR(i);                         \
112         NEXT_OUT(o);                            \
113     } while (0)
114 
115 #define REQUIRE_INBUF(n)                        \
116     do {                                        \
117         if (inleft < (n))                       \
118             return MBERR_TOOFEW;                \
119     } while (0)
120 
121 #define REQUIRE_OUTBUF(n)                       \
122     do {                                        \
123         if (outleft < (n))                      \
124             return MBERR_TOOSMALL;              \
125     } while (0)
126 
127 #define INBYTE1 ((*inbuf)[0])
128 #define INBYTE2 ((*inbuf)[1])
129 #define INBYTE3 ((*inbuf)[2])
130 #define INBYTE4 ((*inbuf)[3])
131 
132 #define INCHAR1 (PyUnicode_READ(kind, data, *inpos))
133 #define INCHAR2 (PyUnicode_READ(kind, data, *inpos + 1))
134 
135 #define OUTCHAR(c)                                                         \
136     do {                                                                   \
137         if (_PyUnicodeWriter_WriteChar(writer, (c)) < 0)                   \
138             return MBERR_EXCEPTION;                                         \
139     } while (0)
140 
141 #define OUTCHAR2(c1, c2)                                                   \
142     do {                                                                   \
143         Py_UCS4 _c1 = (c1);                                                \
144         Py_UCS4 _c2 = (c2);                                                \
145         if (_PyUnicodeWriter_Prepare(writer, 2, Py_MAX(_c1, c2)) < 0)      \
146             return MBERR_EXCEPTION;                                        \
147         PyUnicode_WRITE(writer->kind, writer->data, writer->pos, _c1);     \
148         PyUnicode_WRITE(writer->kind, writer->data, writer->pos + 1, _c2); \
149         writer->pos += 2;                                                  \
150     } while (0)
151 
152 #define OUTBYTEI(c, i)                     \
153     do {                                   \
154         assert((unsigned char)(c) == (c)); \
155         ((*outbuf)[i]) = (c);              \
156     } while (0)
157 
158 #define OUTBYTE1(c) OUTBYTEI(c, 0)
159 #define OUTBYTE2(c) OUTBYTEI(c, 1)
160 #define OUTBYTE3(c) OUTBYTEI(c, 2)
161 #define OUTBYTE4(c) OUTBYTEI(c, 3)
162 
163 #define WRITEBYTE1(c1)              \
164     do {                            \
165         REQUIRE_OUTBUF(1);          \
166         OUTBYTE1(c1);               \
167     } while (0)
168 #define WRITEBYTE2(c1, c2)          \
169     do {                            \
170         REQUIRE_OUTBUF(2);          \
171         OUTBYTE1(c1);               \
172         OUTBYTE2(c2);               \
173     } while (0)
174 #define WRITEBYTE3(c1, c2, c3)      \
175     do {                            \
176         REQUIRE_OUTBUF(3);          \
177         OUTBYTE1(c1);               \
178         OUTBYTE2(c2);               \
179         OUTBYTE3(c3);               \
180     } while (0)
181 #define WRITEBYTE4(c1, c2, c3, c4)  \
182     do {                            \
183         REQUIRE_OUTBUF(4);          \
184         OUTBYTE1(c1);               \
185         OUTBYTE2(c2);               \
186         OUTBYTE3(c3);               \
187         OUTBYTE4(c4);               \
188     } while (0)
189 
190 #define _TRYMAP_ENC(m, assi, val)                               \
191     ((m)->map != NULL && (val) >= (m)->bottom &&                \
192         (val)<= (m)->top && ((assi) = (m)->map[(val) -          \
193         (m)->bottom]) != NOCHAR)
194 #define TRYMAP_ENC(charset, assi, uni)                     \
195     _TRYMAP_ENC(&charset##_encmap[(uni) >> 8], assi, (uni) & 0xff)
196 
197 #define _TRYMAP_DEC(m, assi, val)                             \
198     ((m)->map != NULL &&                                        \
199      (val) >= (m)->bottom &&                                    \
200      (val)<= (m)->top &&                                        \
201      ((assi) = (m)->map[(val) - (m)->bottom]) != UNIINV)
202 #define TRYMAP_DEC(charset, assi, c1, c2)                     \
203     _TRYMAP_DEC(&charset##_decmap[c1], assi, c2)
204 
205 #define BEGIN_MAPPINGS_LIST static const struct dbcs_map _mapping_list[] = {
206 #define MAPPING_ENCONLY(enc) {#enc, (void*)enc##_encmap, NULL},
207 #define MAPPING_DECONLY(enc) {#enc, NULL, (void*)enc##_decmap},
208 #define MAPPING_ENCDEC(enc) {#enc, (void*)enc##_encmap, (void*)enc##_decmap},
209 #define END_MAPPINGS_LIST                               \
210     {"", NULL, NULL} };                                 \
211     static const struct dbcs_map *mapping_list =        \
212         (const struct dbcs_map *)_mapping_list;
213 
214 #define BEGIN_CODECS_LIST static const MultibyteCodec _codec_list[] = {
215 #define _STATEFUL_METHODS(enc)          \
216     enc##_encode,                       \
217     enc##_encode_init,                  \
218     enc##_encode_reset,                 \
219     enc##_decode,                       \
220     enc##_decode_init,                  \
221     enc##_decode_reset,
222 #define _STATELESS_METHODS(enc)         \
223     enc##_encode, NULL, NULL,           \
224     enc##_decode, NULL, NULL,
225 #define CODEC_STATEFUL(enc) {           \
226     #enc, NULL, NULL,                   \
227     _STATEFUL_METHODS(enc)              \
228 },
229 #define CODEC_STATELESS(enc) {          \
230     #enc, NULL, NULL,                   \
231     _STATELESS_METHODS(enc)             \
232 },
233 #define CODEC_STATELESS_WINIT(enc) {    \
234     #enc, NULL,                         \
235     enc##_codec_init,                   \
236     _STATELESS_METHODS(enc)             \
237 },
238 #define END_CODECS_LIST                                 \
239     {"", NULL,} };                                      \
240     static const MultibyteCodec *codec_list =           \
241         (const MultibyteCodec *)_codec_list;
242 
243 
244 
245 static PyObject *
getmultibytecodec(void)246 getmultibytecodec(void)
247 {
248     static PyObject *cofunc = NULL;
249 
250     if (cofunc == NULL) {
251         PyObject *mod = PyImport_ImportModuleNoBlock("_multibytecodec");
252         if (mod == NULL)
253             return NULL;
254         cofunc = PyObject_GetAttrString(mod, "__create_codec");
255         Py_DECREF(mod);
256     }
257     return cofunc;
258 }
259 
260 static PyObject *
getcodec(PyObject * self,PyObject * encoding)261 getcodec(PyObject *self, PyObject *encoding)
262 {
263     PyObject *codecobj, *r, *cofunc;
264     const MultibyteCodec *codec;
265     const char *enc;
266 
267     if (!PyUnicode_Check(encoding)) {
268         PyErr_SetString(PyExc_TypeError,
269                         "encoding name must be a string.");
270         return NULL;
271     }
272     enc = PyUnicode_AsUTF8(encoding);
273     if (enc == NULL)
274         return NULL;
275 
276     cofunc = getmultibytecodec();
277     if (cofunc == NULL)
278         return NULL;
279 
280     for (codec = codec_list; codec->encoding[0]; codec++)
281         if (strcmp(codec->encoding, enc) == 0)
282             break;
283 
284     if (codec->encoding[0] == '\0') {
285         PyErr_SetString(PyExc_LookupError,
286                         "no such codec is supported.");
287         return NULL;
288     }
289 
290     codecobj = PyCapsule_New((void *)codec, PyMultibyteCodec_CAPSULE_NAME, NULL);
291     if (codecobj == NULL)
292         return NULL;
293 
294     r = PyObject_CallFunctionObjArgs(cofunc, codecobj, NULL);
295     Py_DECREF(codecobj);
296 
297     return r;
298 }
299 
300 static struct PyMethodDef __methods[] = {
301     {"getcodec", (PyCFunction)getcodec, METH_O, ""},
302     {NULL, NULL},
303 };
304 
305 static int
register_maps(PyObject * module)306 register_maps(PyObject *module)
307 {
308     const struct dbcs_map *h;
309 
310     for (h = mapping_list; h->charset[0] != '\0'; h++) {
311         char mhname[256] = "__map_";
312         int r;
313         strcpy(mhname + sizeof("__map_") - 1, h->charset);
314         r = PyModule_AddObject(module, mhname,
315                         PyCapsule_New((void *)h, PyMultibyteCodec_CAPSULE_NAME, NULL));
316         if (r == -1)
317             return -1;
318     }
319     return 0;
320 }
321 
322 #ifdef USING_BINARY_PAIR_SEARCH
323 static DBCHAR
find_pairencmap(ucs2_t body,ucs2_t modifier,const struct pair_encodemap * haystack,int haystacksize)324 find_pairencmap(ucs2_t body, ucs2_t modifier,
325                 const struct pair_encodemap *haystack, int haystacksize)
326 {
327     int pos, min, max;
328     Py_UCS4 value = body << 16 | modifier;
329 
330     min = 0;
331     max = haystacksize;
332 
333     for (pos = haystacksize >> 1; min != max; pos = (min + max) >> 1) {
334         if (value < haystack[pos].uniseq) {
335             if (max != pos) {
336                 max = pos;
337                 continue;
338             }
339         }
340         else if (value > haystack[pos].uniseq) {
341             if (min != pos) {
342                 min = pos;
343                 continue;
344             }
345         }
346         break;
347     }
348 
349     if (value == haystack[pos].uniseq) {
350         return haystack[pos].code;
351     }
352     return DBCINV;
353 }
354 #endif
355 
356 #ifdef USING_IMPORTED_MAPS
357 #define IMPORT_MAP(locale, charset, encmap, decmap) \
358     importmap("_codecs_" #locale, "__map_" #charset, \
359               (const void**)encmap, (const void**)decmap)
360 
361 static int
importmap(const char * modname,const char * symbol,const void ** encmap,const void ** decmap)362 importmap(const char *modname, const char *symbol,
363           const void **encmap, const void **decmap)
364 {
365     PyObject *o, *mod;
366 
367     mod = PyImport_ImportModule(modname);
368     if (mod == NULL)
369         return -1;
370 
371     o = PyObject_GetAttrString(mod, symbol);
372     if (o == NULL)
373         goto errorexit;
374     else if (!PyCapsule_IsValid(o, PyMultibyteCodec_CAPSULE_NAME)) {
375         PyErr_SetString(PyExc_ValueError,
376                         "map data must be a Capsule.");
377         goto errorexit;
378     }
379     else {
380         struct dbcs_map *map;
381         map = PyCapsule_GetPointer(o, PyMultibyteCodec_CAPSULE_NAME);
382         if (encmap != NULL)
383             *encmap = map->encmap;
384         if (decmap != NULL)
385             *decmap = map->decmap;
386         Py_DECREF(o);
387     }
388 
389     Py_DECREF(mod);
390     return 0;
391 
392 errorexit:
393     Py_DECREF(mod);
394     return -1;
395 }
396 #endif
397 
398 #define I_AM_A_MODULE_FOR(loc)                                          \
399     static struct PyModuleDef __module = {                              \
400         PyModuleDef_HEAD_INIT,                                          \
401         "_codecs_"#loc,                                                 \
402         NULL,                                                           \
403         0,                                                              \
404         __methods,                                                      \
405         NULL,                                                           \
406         NULL,                                                           \
407         NULL,                                                           \
408         NULL                                                            \
409     };                                                                  \
410     PyMODINIT_FUNC                                                      \
411     PyInit__codecs_##loc(void)                                          \
412     {                                                                   \
413         PyObject *m = PyModule_Create(&__module);                       \
414         if (m != NULL)                                                  \
415             (void)register_maps(m);                                     \
416         return m;                                                       \
417     }
418 
419 #endif
420