Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 1 | /*********************************************************** |
| 2 | Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam, |
| 3 | The Netherlands. |
| 4 | |
| 5 | All Rights Reserved |
| 6 | |
| 7 | Permission to use, copy, modify, and distribute this software and its |
| 8 | documentation for any purpose and without fee is hereby granted, |
| 9 | provided that the above copyright notice appear in all copies and that |
| 10 | both that copyright notice and this permission notice appear in |
| 11 | supporting documentation, and that the names of Stichting Mathematisch |
| 12 | Centrum or CWI or Corporation for National Research Initiatives or |
| 13 | CNRI not be used in advertising or publicity pertaining to |
| 14 | distribution of the software without specific, written prior |
| 15 | permission. |
| 16 | |
| 17 | While CWI is the initial source for this software, a modified version |
| 18 | is made available by the Corporation for National Research Initiatives |
| 19 | (CNRI) at the Internet address ftp://ftp.python.org. |
| 20 | |
| 21 | STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH |
| 22 | REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF |
| 23 | MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH |
| 24 | CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL |
| 25 | DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR |
| 26 | PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER |
| 27 | TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR |
| 28 | PERFORMANCE OF THIS SOFTWARE. |
| 29 | |
| 30 | ******************************************************************/ |
| 31 | |
| 32 | /* Buffer object implementation */ |
| 33 | |
| 34 | #include "Python.h" |
| 35 | |
| 36 | |
| 37 | typedef struct { |
| 38 | PyObject_HEAD |
| 39 | PyObject *b_base; |
| 40 | void *b_ptr; |
| 41 | int b_size; |
| 42 | int b_readonly; |
| 43 | #ifdef CACHE_HASH |
| 44 | long b_hash; |
| 45 | #endif |
| 46 | } PyBufferObject; |
| 47 | |
| 48 | |
| 49 | static PyObject * |
| 50 | _PyBuffer_FromMemory(base, ptr, size, readonly) |
| 51 | PyObject *base; |
| 52 | void *ptr; |
| 53 | int size; |
| 54 | int readonly; |
| 55 | { |
| 56 | PyBufferObject * b; |
| 57 | |
Guido van Rossum | 49ded3e | 1999-03-19 19:04:25 +0000 | [diff] [blame] | 58 | if ( size < 0 ) { |
| 59 | PyErr_SetString(PyExc_ValueError, |
| 60 | "size must be zero or positive"); |
| 61 | return NULL; |
| 62 | } |
| 63 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 64 | b = PyObject_NEW(PyBufferObject, &PyBuffer_Type); |
| 65 | if ( b == NULL ) |
| 66 | return NULL; |
| 67 | |
| 68 | Py_XINCREF(base); |
| 69 | b->b_base = base; |
| 70 | b->b_ptr = ptr; |
| 71 | b->b_size = size; |
| 72 | b->b_readonly = readonly; |
| 73 | #ifdef CACHE_HASH |
| 74 | b->b_hash = -1; |
| 75 | #endif |
| 76 | |
| 77 | return (PyObject *) b; |
| 78 | } |
| 79 | |
| 80 | static PyObject * |
| 81 | _PyBuffer_FromObject(base, offset, size, proc, readonly) |
| 82 | PyObject *base; |
| 83 | int offset; |
| 84 | int size; |
| 85 | getreadbufferproc proc; |
| 86 | int readonly; |
| 87 | { |
| 88 | PyBufferProcs *pb = base->ob_type->tp_as_buffer; |
| 89 | void *p; |
| 90 | int count; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 91 | |
Guido van Rossum | 49ded3e | 1999-03-19 19:04:25 +0000 | [diff] [blame] | 92 | if ( offset < 0 ) { |
| 93 | PyErr_SetString(PyExc_ValueError, |
| 94 | "offset must be zero or positive"); |
| 95 | return NULL; |
| 96 | } |
| 97 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 98 | if ( (*pb->bf_getsegcount)(base, NULL) != 1 ) |
| 99 | { |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 100 | PyErr_SetString(PyExc_TypeError, |
| 101 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 102 | return NULL; |
| 103 | } |
| 104 | if ( (count = (*proc)(base, 0, &p)) < 0 ) |
| 105 | return NULL; |
| 106 | |
| 107 | /* apply constraints to the start/end */ |
Guido van Rossum | 49ded3e | 1999-03-19 19:04:25 +0000 | [diff] [blame] | 108 | if ( size == Py_END_OF_BUFFER || size < 0 ) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 109 | size = count; |
| 110 | if ( offset > count ) |
| 111 | offset = count; |
| 112 | if ( offset + size > count ) |
| 113 | size = count - offset; |
| 114 | |
| 115 | /* if the base object is another buffer, then "deref" it */ |
| 116 | if ( PyBuffer_Check(base) ) |
| 117 | base = ((PyBufferObject *)base)->b_base; |
| 118 | |
| 119 | return _PyBuffer_FromMemory(base, (char *)p + offset, size, readonly); |
| 120 | } |
| 121 | |
| 122 | |
| 123 | PyObject * |
| 124 | PyBuffer_FromObject(base, offset, size) |
| 125 | PyObject *base; |
| 126 | int offset; |
| 127 | int size; |
| 128 | { |
| 129 | PyBufferProcs *pb = base->ob_type->tp_as_buffer; |
| 130 | |
| 131 | if ( pb == NULL || |
| 132 | pb->bf_getreadbuffer == NULL || |
| 133 | pb->bf_getsegcount == NULL ) |
| 134 | { |
| 135 | PyErr_SetString(PyExc_TypeError, "buffer object expected"); |
| 136 | return NULL; |
| 137 | } |
| 138 | |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 139 | return _PyBuffer_FromObject(base, offset, size, |
| 140 | pb->bf_getreadbuffer, 1); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 141 | } |
| 142 | |
| 143 | PyObject * |
| 144 | PyBuffer_FromReadWriteObject(base, offset, size) |
| 145 | PyObject *base; |
| 146 | int offset; |
| 147 | int size; |
| 148 | { |
| 149 | PyBufferProcs *pb = base->ob_type->tp_as_buffer; |
| 150 | |
| 151 | if ( pb == NULL || |
| 152 | pb->bf_getwritebuffer == NULL || |
| 153 | pb->bf_getsegcount == NULL ) |
| 154 | { |
| 155 | PyErr_SetString(PyExc_TypeError, "buffer object expected"); |
| 156 | return NULL; |
| 157 | } |
| 158 | |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 159 | return _PyBuffer_FromObject(base, offset, size, |
| 160 | (getreadbufferproc)pb->bf_getwritebuffer, |
| 161 | 0); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 162 | } |
| 163 | |
| 164 | PyObject * |
| 165 | PyBuffer_FromMemory(ptr, size) |
| 166 | void *ptr; |
| 167 | int size; |
| 168 | { |
| 169 | return _PyBuffer_FromMemory(NULL, ptr, size, 1); |
| 170 | } |
| 171 | |
| 172 | PyObject * |
| 173 | PyBuffer_FromReadWriteMemory(ptr, size) |
| 174 | void *ptr; |
| 175 | int size; |
| 176 | { |
| 177 | return _PyBuffer_FromMemory(NULL, ptr, size, 0); |
| 178 | } |
| 179 | |
| 180 | PyObject * |
| 181 | PyBuffer_New(size) |
| 182 | int size; |
| 183 | { |
| 184 | PyBufferObject * b; |
| 185 | |
Fred Drake | 4574f23 | 1999-08-04 13:08:19 +0000 | [diff] [blame] | 186 | if (size < 0) { |
| 187 | PyErr_SetString(PyExc_ValueError, |
| 188 | "size must be zero or positive"); |
| 189 | return NULL; |
| 190 | } |
Guido van Rossum | b18618d | 2000-05-03 23:44:39 +0000 | [diff] [blame] | 191 | /* PyObject_New is inlined */ |
| 192 | b = (PyBufferObject *) PyObject_MALLOC(sizeof(*b) + size); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 193 | if ( b == NULL ) |
Fred Drake | 4574f23 | 1999-08-04 13:08:19 +0000 | [diff] [blame] | 194 | return PyErr_NoMemory(); |
Guido van Rossum | b18618d | 2000-05-03 23:44:39 +0000 | [diff] [blame] | 195 | PyObject_INIT((PyObject *)b, &PyBuffer_Type); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 196 | |
| 197 | b->b_base = NULL; |
| 198 | b->b_ptr = (void *)(b + 1); |
| 199 | b->b_size = size; |
| 200 | b->b_readonly = 0; |
| 201 | #ifdef CACHE_HASH |
| 202 | b->b_hash = -1; |
| 203 | #endif |
| 204 | |
| 205 | return (PyObject *) b; |
| 206 | } |
| 207 | |
| 208 | /* Methods */ |
| 209 | |
| 210 | static void |
| 211 | buffer_dealloc(self) |
| 212 | PyBufferObject *self; |
| 213 | { |
| 214 | Py_XDECREF(self->b_base); |
Guido van Rossum | b18618d | 2000-05-03 23:44:39 +0000 | [diff] [blame] | 215 | PyObject_DEL(self); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 216 | } |
| 217 | |
| 218 | static int |
| 219 | buffer_compare(self, other) |
| 220 | PyBufferObject *self; |
| 221 | PyBufferObject *other; |
| 222 | { |
| 223 | int len_self = self->b_size; |
| 224 | int len_other = other->b_size; |
| 225 | int min_len = (len_self < len_other) ? len_self : len_other; |
| 226 | int cmp; |
| 227 | if (min_len > 0) { |
| 228 | cmp = memcmp(self->b_ptr, other->b_ptr, min_len); |
| 229 | if (cmp != 0) |
| 230 | return cmp; |
| 231 | } |
| 232 | return (len_self < len_other) ? -1 : (len_self > len_other) ? 1 : 0; |
| 233 | } |
| 234 | |
| 235 | static PyObject * |
| 236 | buffer_repr(self) |
| 237 | PyBufferObject *self; |
| 238 | { |
| 239 | char buf[300]; |
| 240 | char *status = self->b_readonly ? "read-only" : "read-write"; |
| 241 | |
| 242 | if ( self->b_base == NULL ) |
| 243 | { |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 244 | sprintf(buf, "<%s buffer ptr %p, size %d at %p>", |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 245 | status, |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 246 | self->b_ptr, |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 247 | self->b_size, |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 248 | self); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 249 | } |
| 250 | else |
| 251 | { |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 252 | sprintf(buf, "<%s buffer for %p, ptr %p, size %d at %p>", |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 253 | status, |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 254 | self->b_base, |
| 255 | self->b_ptr, |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 256 | self->b_size, |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 257 | self); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 258 | } |
| 259 | |
| 260 | return PyString_FromString(buf); |
| 261 | } |
| 262 | |
| 263 | static long |
| 264 | buffer_hash(self) |
| 265 | PyBufferObject *self; |
| 266 | { |
| 267 | register int len; |
| 268 | register unsigned char *p; |
| 269 | register long x; |
| 270 | |
| 271 | #ifdef CACHE_HASH |
| 272 | if ( self->b_hash != -1 ) |
| 273 | return self->b_hash; |
| 274 | #endif |
| 275 | |
| 276 | if ( !self->b_readonly ) |
| 277 | { |
| 278 | /* ### use different wording, since this is conditional? */ |
| 279 | PyErr_SetString(PyExc_TypeError, "unhashable type"); |
| 280 | return -1; |
| 281 | } |
| 282 | |
| 283 | len = self->b_size; |
| 284 | p = (unsigned char *) self->b_ptr; |
| 285 | x = *p << 7; |
| 286 | while (--len >= 0) |
| 287 | x = (1000003*x) ^ *p++; |
| 288 | x ^= self->b_size; |
| 289 | if (x == -1) |
| 290 | x = -2; |
| 291 | #ifdef CACHE_HASH |
| 292 | self->b_hash = x; |
| 293 | #endif |
| 294 | return x; |
| 295 | } |
| 296 | |
| 297 | static PyObject * |
| 298 | buffer_str(self) |
| 299 | PyBufferObject *self; |
| 300 | { |
| 301 | return PyString_FromStringAndSize(self->b_ptr, self->b_size); |
| 302 | } |
| 303 | |
| 304 | /* Sequence methods */ |
| 305 | |
| 306 | static int |
| 307 | buffer_length(self) |
| 308 | PyBufferObject *self; |
| 309 | { |
| 310 | return self->b_size; |
| 311 | } |
| 312 | |
| 313 | static PyObject * |
| 314 | buffer_concat(self, other) |
| 315 | PyBufferObject *self; |
| 316 | PyObject *other; |
| 317 | { |
| 318 | PyBufferProcs *pb = other->ob_type->tp_as_buffer; |
| 319 | char *p1; |
| 320 | void *p2; |
| 321 | PyObject *ob; |
| 322 | int count; |
| 323 | |
| 324 | if ( pb == NULL || |
| 325 | pb->bf_getreadbuffer == NULL || |
| 326 | pb->bf_getsegcount == NULL ) |
| 327 | { |
| 328 | PyErr_BadArgument(); |
| 329 | return NULL; |
| 330 | } |
| 331 | if ( (*pb->bf_getsegcount)(other, NULL) != 1 ) |
| 332 | { |
| 333 | /* ### use a different exception type/message? */ |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 334 | PyErr_SetString(PyExc_TypeError, |
| 335 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 336 | return NULL; |
| 337 | } |
| 338 | |
| 339 | /* optimize special case */ |
| 340 | if ( self->b_size == 0 ) |
| 341 | { |
| 342 | Py_INCREF(other); |
| 343 | return other; |
| 344 | } |
| 345 | |
| 346 | if ( (count = (*pb->bf_getreadbuffer)(other, 0, &p2)) < 0 ) |
| 347 | return NULL; |
| 348 | |
| 349 | /* optimize special case */ |
| 350 | if ( count == 0 ) |
| 351 | { |
| 352 | Py_INCREF(self); |
| 353 | return (PyObject *)self; |
| 354 | } |
| 355 | |
| 356 | ob = PyString_FromStringAndSize(NULL, self->b_size + count); |
| 357 | p1 = PyString_AS_STRING(ob); |
| 358 | memcpy(p1, self->b_ptr, self->b_size); |
| 359 | memcpy(p1 + self->b_size, p2, count); |
| 360 | |
| 361 | /* there is an extra byte in the string object, so this is safe */ |
| 362 | p1[self->b_size + count] = '\0'; |
| 363 | |
| 364 | return ob; |
| 365 | } |
| 366 | |
| 367 | static PyObject * |
| 368 | buffer_repeat(self, count) |
| 369 | PyBufferObject *self; |
| 370 | int count; |
| 371 | { |
| 372 | PyObject *ob; |
| 373 | register char *p; |
| 374 | void *ptr = self->b_ptr; |
| 375 | int size = self->b_size; |
| 376 | |
| 377 | if ( count < 0 ) |
| 378 | count = 0; |
| 379 | ob = PyString_FromStringAndSize(NULL, size * count); |
| 380 | if ( ob == NULL ) |
| 381 | return NULL; |
| 382 | |
| 383 | p = PyString_AS_STRING(ob); |
| 384 | while ( count-- ) |
| 385 | { |
| 386 | memcpy(p, ptr, size); |
| 387 | p += size; |
| 388 | } |
| 389 | |
| 390 | /* there is an extra byte in the string object, so this is safe */ |
| 391 | *p = '\0'; |
| 392 | |
| 393 | return ob; |
| 394 | } |
| 395 | |
| 396 | static PyObject * |
| 397 | buffer_item(self, idx) |
| 398 | PyBufferObject *self; |
| 399 | int idx; |
| 400 | { |
| 401 | if ( idx < 0 || idx >= self->b_size ) |
| 402 | { |
| 403 | PyErr_SetString(PyExc_IndexError, "buffer index out of range"); |
| 404 | return NULL; |
| 405 | } |
| 406 | return PyString_FromStringAndSize((char *)self->b_ptr + idx, 1); |
| 407 | } |
| 408 | |
| 409 | static PyObject * |
| 410 | buffer_slice(self, left, right) |
| 411 | PyBufferObject *self; |
| 412 | int left; |
| 413 | int right; |
| 414 | { |
| 415 | if ( left < 0 ) |
| 416 | left = 0; |
| 417 | if ( right < 0 ) |
| 418 | right = 0; |
| 419 | if ( right > self->b_size ) |
| 420 | right = self->b_size; |
| 421 | if ( left == 0 && right == self->b_size ) |
| 422 | { |
| 423 | /* same as self */ |
| 424 | Py_INCREF(self); |
| 425 | return (PyObject *)self; |
| 426 | } |
| 427 | if ( right < left ) |
| 428 | right = left; |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 429 | return PyString_FromStringAndSize((char *)self->b_ptr + left, |
| 430 | right - left); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 431 | } |
| 432 | |
| 433 | static int |
| 434 | buffer_ass_item(self, idx, other) |
| 435 | PyBufferObject *self; |
| 436 | int idx; |
| 437 | PyObject *other; |
| 438 | { |
| 439 | PyBufferProcs *pb; |
| 440 | void *p; |
| 441 | int count; |
| 442 | |
| 443 | if ( self->b_readonly ) { |
| 444 | PyErr_SetString(PyExc_TypeError, |
| 445 | "buffer is read-only"); |
| 446 | return -1; |
| 447 | } |
| 448 | |
| 449 | if (idx < 0 || idx >= self->b_size) { |
| 450 | PyErr_SetString(PyExc_IndexError, |
| 451 | "buffer assignment index out of range"); |
| 452 | return -1; |
| 453 | } |
| 454 | |
| 455 | pb = other ? other->ob_type->tp_as_buffer : NULL; |
| 456 | if ( pb == NULL || |
| 457 | pb->bf_getreadbuffer == NULL || |
| 458 | pb->bf_getsegcount == NULL ) |
| 459 | { |
| 460 | PyErr_BadArgument(); |
| 461 | return -1; |
| 462 | } |
| 463 | if ( (*pb->bf_getsegcount)(other, NULL) != 1 ) |
| 464 | { |
| 465 | /* ### use a different exception type/message? */ |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 466 | PyErr_SetString(PyExc_TypeError, |
| 467 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 468 | return -1; |
| 469 | } |
| 470 | |
| 471 | if ( (count = (*pb->bf_getreadbuffer)(other, 0, &p)) < 0 ) |
| 472 | return -1; |
| 473 | if ( count != 1 ) { |
| 474 | PyErr_SetString(PyExc_TypeError, |
| 475 | "right operand must be a single byte"); |
| 476 | return -1; |
| 477 | } |
| 478 | |
| 479 | ((char *)self->b_ptr)[idx] = *(char *)p; |
| 480 | return 0; |
| 481 | } |
| 482 | |
| 483 | static int |
| 484 | buffer_ass_slice(self, left, right, other) |
| 485 | PyBufferObject *self; |
| 486 | int left; |
| 487 | int right; |
| 488 | PyObject *other; |
| 489 | { |
| 490 | PyBufferProcs *pb; |
| 491 | void *p; |
| 492 | int slice_len; |
| 493 | int count; |
| 494 | |
| 495 | if ( self->b_readonly ) { |
| 496 | PyErr_SetString(PyExc_TypeError, |
| 497 | "buffer is read-only"); |
| 498 | return -1; |
| 499 | } |
| 500 | |
| 501 | pb = other ? other->ob_type->tp_as_buffer : NULL; |
| 502 | if ( pb == NULL || |
| 503 | pb->bf_getreadbuffer == NULL || |
| 504 | pb->bf_getsegcount == NULL ) |
| 505 | { |
| 506 | PyErr_BadArgument(); |
| 507 | return -1; |
| 508 | } |
| 509 | if ( (*pb->bf_getsegcount)(other, NULL) != 1 ) |
| 510 | { |
| 511 | /* ### use a different exception type/message? */ |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 512 | PyErr_SetString(PyExc_TypeError, |
| 513 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 514 | return -1; |
| 515 | } |
| 516 | if ( (count = (*pb->bf_getreadbuffer)(other, 0, &p)) < 0 ) |
| 517 | return -1; |
| 518 | |
| 519 | if ( left < 0 ) |
| 520 | left = 0; |
| 521 | else if ( left > self->b_size ) |
| 522 | left = self->b_size; |
| 523 | if ( right < left ) |
| 524 | right = left; |
| 525 | else if ( right > self->b_size ) |
| 526 | right = self->b_size; |
| 527 | slice_len = right - left; |
| 528 | |
| 529 | if ( count != slice_len ) { |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 530 | PyErr_SetString( |
| 531 | PyExc_TypeError, |
| 532 | "right operand length must match slice length"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 533 | return -1; |
| 534 | } |
| 535 | |
| 536 | if ( slice_len ) |
| 537 | memcpy((char *)self->b_ptr + left, p, slice_len); |
| 538 | |
| 539 | return 0; |
| 540 | } |
| 541 | |
| 542 | /* Buffer methods */ |
| 543 | |
| 544 | static int |
| 545 | buffer_getreadbuf(self, idx, pp) |
| 546 | PyBufferObject *self; |
| 547 | int idx; |
| 548 | void ** pp; |
| 549 | { |
| 550 | if ( idx != 0 ) { |
| 551 | PyErr_SetString(PyExc_SystemError, |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 552 | "accessing non-existent buffer segment"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 553 | return -1; |
| 554 | } |
| 555 | *pp = self->b_ptr; |
| 556 | return self->b_size; |
| 557 | } |
| 558 | |
| 559 | static int |
| 560 | buffer_getwritebuf(self, idx, pp) |
| 561 | PyBufferObject *self; |
| 562 | int idx; |
| 563 | void ** pp; |
| 564 | { |
| 565 | if ( self->b_readonly ) |
| 566 | { |
| 567 | PyErr_SetString(PyExc_TypeError, "buffer is read-only"); |
| 568 | return -1; |
| 569 | } |
| 570 | return buffer_getreadbuf(self, idx, pp); |
| 571 | } |
| 572 | |
| 573 | static int |
| 574 | buffer_getsegcount(self, lenp) |
| 575 | PyBufferObject *self; |
| 576 | int *lenp; |
| 577 | { |
| 578 | if ( lenp ) |
| 579 | *lenp = self->b_size; |
| 580 | return 1; |
| 581 | } |
| 582 | |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 583 | static int |
| 584 | buffer_getcharbuf(self, idx, pp) |
| 585 | PyBufferObject *self; |
| 586 | int idx; |
| 587 | const char ** pp; |
| 588 | { |
| 589 | if ( idx != 0 ) { |
| 590 | PyErr_SetString(PyExc_SystemError, |
| 591 | "accessing non-existent buffer segment"); |
| 592 | return -1; |
| 593 | } |
| 594 | *pp = (const char *)self->b_ptr; |
| 595 | return self->b_size; |
| 596 | } |
| 597 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 598 | |
| 599 | static PySequenceMethods buffer_as_sequence = { |
| 600 | (inquiry)buffer_length, /*sq_length*/ |
| 601 | (binaryfunc)buffer_concat, /*sq_concat*/ |
| 602 | (intargfunc)buffer_repeat, /*sq_repeat*/ |
| 603 | (intargfunc)buffer_item, /*sq_item*/ |
| 604 | (intintargfunc)buffer_slice, /*sq_slice*/ |
| 605 | (intobjargproc)buffer_ass_item, /*sq_ass_item*/ |
| 606 | (intintobjargproc)buffer_ass_slice, /*sq_ass_slice*/ |
| 607 | }; |
| 608 | |
| 609 | static PyBufferProcs buffer_as_buffer = { |
| 610 | (getreadbufferproc)buffer_getreadbuf, |
| 611 | (getwritebufferproc)buffer_getwritebuf, |
| 612 | (getsegcountproc)buffer_getsegcount, |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 613 | (getcharbufferproc)buffer_getcharbuf, |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 614 | }; |
| 615 | |
| 616 | PyTypeObject PyBuffer_Type = { |
| 617 | PyObject_HEAD_INIT(&PyType_Type) |
| 618 | 0, |
| 619 | "buffer", |
| 620 | sizeof(PyBufferObject), |
| 621 | 0, |
| 622 | (destructor)buffer_dealloc, /*tp_dealloc*/ |
| 623 | 0, /*tp_print*/ |
| 624 | 0, /*tp_getattr*/ |
| 625 | 0, /*tp_setattr*/ |
| 626 | (cmpfunc)buffer_compare, /*tp_compare*/ |
| 627 | (reprfunc)buffer_repr, /*tp_repr*/ |
| 628 | 0, /*tp_as_number*/ |
| 629 | &buffer_as_sequence, /*tp_as_sequence*/ |
| 630 | 0, /*tp_as_mapping*/ |
| 631 | (hashfunc)buffer_hash, /*tp_hash*/ |
| 632 | 0, /*tp_call*/ |
| 633 | (reprfunc)buffer_str, /*tp_str*/ |
| 634 | 0, /*tp_getattro*/ |
| 635 | 0, /*tp_setattro*/ |
| 636 | &buffer_as_buffer, /*tp_as_buffer*/ |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 637 | Py_TPFLAGS_DEFAULT, /*tp_flags*/ |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 638 | 0, /*tp_doc*/ |
| 639 | }; |
| 640 | |