Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 1 | |
| 2 | /* Buffer object implementation */ |
| 3 | |
| 4 | #include "Python.h" |
| 5 | |
| 6 | |
| 7 | typedef struct { |
| 8 | PyObject_HEAD |
| 9 | PyObject *b_base; |
| 10 | void *b_ptr; |
| 11 | int b_size; |
| 12 | int b_readonly; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 13 | long b_hash; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 14 | } PyBufferObject; |
| 15 | |
| 16 | |
| 17 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 18 | _PyBuffer_FromMemory(PyObject *base, void *ptr, int size, int readonly) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 19 | { |
| 20 | PyBufferObject * b; |
| 21 | |
Guido van Rossum | 49ded3e | 1999-03-19 19:04:25 +0000 | [diff] [blame] | 22 | if ( size < 0 ) { |
| 23 | PyErr_SetString(PyExc_ValueError, |
| 24 | "size must be zero or positive"); |
| 25 | return NULL; |
| 26 | } |
| 27 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 28 | b = PyObject_NEW(PyBufferObject, &PyBuffer_Type); |
| 29 | if ( b == NULL ) |
| 30 | return NULL; |
| 31 | |
| 32 | Py_XINCREF(base); |
| 33 | b->b_base = base; |
| 34 | b->b_ptr = ptr; |
| 35 | b->b_size = size; |
| 36 | b->b_readonly = readonly; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 37 | b->b_hash = -1; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 38 | |
| 39 | return (PyObject *) b; |
| 40 | } |
| 41 | |
| 42 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 43 | _PyBuffer_FromObject(PyObject *base, int offset, int size, |
| 44 | getreadbufferproc proc, int readonly) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 45 | { |
| 46 | PyBufferProcs *pb = base->ob_type->tp_as_buffer; |
| 47 | void *p; |
| 48 | int count; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 49 | |
Guido van Rossum | 49ded3e | 1999-03-19 19:04:25 +0000 | [diff] [blame] | 50 | if ( offset < 0 ) { |
| 51 | PyErr_SetString(PyExc_ValueError, |
| 52 | "offset must be zero or positive"); |
| 53 | return NULL; |
| 54 | } |
| 55 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 56 | if ( (*pb->bf_getsegcount)(base, NULL) != 1 ) |
| 57 | { |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 58 | PyErr_SetString(PyExc_TypeError, |
| 59 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 60 | return NULL; |
| 61 | } |
| 62 | if ( (count = (*proc)(base, 0, &p)) < 0 ) |
| 63 | return NULL; |
| 64 | |
| 65 | /* apply constraints to the start/end */ |
Guido van Rossum | 49ded3e | 1999-03-19 19:04:25 +0000 | [diff] [blame] | 66 | if ( size == Py_END_OF_BUFFER || size < 0 ) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 67 | size = count; |
| 68 | if ( offset > count ) |
| 69 | offset = count; |
| 70 | if ( offset + size > count ) |
| 71 | size = count - offset; |
Thomas Heller | fdc1bd3 | 2001-10-19 13:49:35 +0000 | [diff] [blame] | 72 | |
| 73 | /* if the base object is another buffer, then "deref" it, |
| 74 | * except if the base of the other buffer is NULL |
| 75 | */ |
| 76 | if ( PyBuffer_Check(base) && (((PyBufferObject *)base)->b_base) ) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 77 | base = ((PyBufferObject *)base)->b_base; |
Thomas Heller | fdc1bd3 | 2001-10-19 13:49:35 +0000 | [diff] [blame] | 78 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 79 | return _PyBuffer_FromMemory(base, (char *)p + offset, size, readonly); |
| 80 | } |
| 81 | |
| 82 | |
| 83 | PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 84 | PyBuffer_FromObject(PyObject *base, int offset, int size) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 85 | { |
| 86 | PyBufferProcs *pb = base->ob_type->tp_as_buffer; |
| 87 | |
| 88 | if ( pb == NULL || |
| 89 | pb->bf_getreadbuffer == NULL || |
| 90 | pb->bf_getsegcount == NULL ) |
| 91 | { |
| 92 | PyErr_SetString(PyExc_TypeError, "buffer object expected"); |
| 93 | return NULL; |
| 94 | } |
| 95 | |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 96 | return _PyBuffer_FromObject(base, offset, size, |
| 97 | pb->bf_getreadbuffer, 1); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 98 | } |
| 99 | |
| 100 | PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 101 | PyBuffer_FromReadWriteObject(PyObject *base, int offset, int size) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 102 | { |
| 103 | PyBufferProcs *pb = base->ob_type->tp_as_buffer; |
| 104 | |
| 105 | if ( pb == NULL || |
| 106 | pb->bf_getwritebuffer == NULL || |
| 107 | pb->bf_getsegcount == NULL ) |
| 108 | { |
| 109 | PyErr_SetString(PyExc_TypeError, "buffer object expected"); |
| 110 | return NULL; |
| 111 | } |
| 112 | |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 113 | return _PyBuffer_FromObject(base, offset, size, |
| 114 | (getreadbufferproc)pb->bf_getwritebuffer, |
| 115 | 0); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 116 | } |
| 117 | |
| 118 | PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 119 | PyBuffer_FromMemory(void *ptr, int size) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 120 | { |
| 121 | return _PyBuffer_FromMemory(NULL, ptr, size, 1); |
| 122 | } |
| 123 | |
| 124 | PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 125 | PyBuffer_FromReadWriteMemory(void *ptr, int size) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 126 | { |
| 127 | return _PyBuffer_FromMemory(NULL, ptr, size, 0); |
| 128 | } |
| 129 | |
| 130 | PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 131 | PyBuffer_New(int size) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 132 | { |
Moshe Zadka | cf703f0 | 2000-08-04 15:36:13 +0000 | [diff] [blame] | 133 | PyObject *o; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 134 | PyBufferObject * b; |
| 135 | |
Fred Drake | 4574f23 | 1999-08-04 13:08:19 +0000 | [diff] [blame] | 136 | if (size < 0) { |
| 137 | PyErr_SetString(PyExc_ValueError, |
| 138 | "size must be zero or positive"); |
| 139 | return NULL; |
| 140 | } |
Guido van Rossum | b18618d | 2000-05-03 23:44:39 +0000 | [diff] [blame] | 141 | /* PyObject_New is inlined */ |
Moshe Zadka | cf703f0 | 2000-08-04 15:36:13 +0000 | [diff] [blame] | 142 | o = PyObject_MALLOC(sizeof(*b) + size); |
| 143 | if ( o == NULL ) |
Fred Drake | 4574f23 | 1999-08-04 13:08:19 +0000 | [diff] [blame] | 144 | return PyErr_NoMemory(); |
Moshe Zadka | cf703f0 | 2000-08-04 15:36:13 +0000 | [diff] [blame] | 145 | b = (PyBufferObject *) PyObject_INIT(o, &PyBuffer_Type); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 146 | |
| 147 | b->b_base = NULL; |
| 148 | b->b_ptr = (void *)(b + 1); |
| 149 | b->b_size = size; |
| 150 | b->b_readonly = 0; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 151 | b->b_hash = -1; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 152 | |
Moshe Zadka | cf703f0 | 2000-08-04 15:36:13 +0000 | [diff] [blame] | 153 | return o; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 154 | } |
| 155 | |
| 156 | /* Methods */ |
| 157 | |
| 158 | static void |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 159 | buffer_dealloc(PyBufferObject *self) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 160 | { |
| 161 | Py_XDECREF(self->b_base); |
Guido van Rossum | b18618d | 2000-05-03 23:44:39 +0000 | [diff] [blame] | 162 | PyObject_DEL(self); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 163 | } |
| 164 | |
| 165 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 166 | buffer_compare(PyBufferObject *self, PyBufferObject *other) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 167 | { |
| 168 | int len_self = self->b_size; |
| 169 | int len_other = other->b_size; |
| 170 | int min_len = (len_self < len_other) ? len_self : len_other; |
| 171 | int cmp; |
| 172 | if (min_len > 0) { |
| 173 | cmp = memcmp(self->b_ptr, other->b_ptr, min_len); |
| 174 | if (cmp != 0) |
| 175 | return cmp; |
| 176 | } |
| 177 | return (len_self < len_other) ? -1 : (len_self > len_other) ? 1 : 0; |
| 178 | } |
| 179 | |
| 180 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 181 | buffer_repr(PyBufferObject *self) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 182 | { |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 183 | char *status = self->b_readonly ? "read-only" : "read-write"; |
| 184 | |
| 185 | if ( self->b_base == NULL ) |
Barry Warsaw | 7ce3694 | 2001-08-24 18:34:26 +0000 | [diff] [blame] | 186 | return PyString_FromFormat("<%s buffer ptr %p, size %d at %p>", |
| 187 | status, |
| 188 | self->b_ptr, |
| 189 | self->b_size, |
| 190 | self); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 191 | else |
Barry Warsaw | 7ce3694 | 2001-08-24 18:34:26 +0000 | [diff] [blame] | 192 | return PyString_FromFormat( |
| 193 | "<%s buffer for %p, ptr %p, size %d at %p>", |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 194 | status, |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 195 | self->b_base, |
| 196 | self->b_ptr, |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 197 | self->b_size, |
Fred Drake | a44d353 | 2000-06-30 15:01:00 +0000 | [diff] [blame] | 198 | self); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 199 | } |
| 200 | |
| 201 | static long |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 202 | buffer_hash(PyBufferObject *self) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 203 | { |
| 204 | register int len; |
| 205 | register unsigned char *p; |
| 206 | register long x; |
| 207 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 208 | if ( self->b_hash != -1 ) |
| 209 | return self->b_hash; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 210 | |
| 211 | if ( !self->b_readonly ) |
| 212 | { |
| 213 | /* ### use different wording, since this is conditional? */ |
| 214 | PyErr_SetString(PyExc_TypeError, "unhashable type"); |
| 215 | return -1; |
| 216 | } |
| 217 | |
| 218 | len = self->b_size; |
| 219 | p = (unsigned char *) self->b_ptr; |
| 220 | x = *p << 7; |
| 221 | while (--len >= 0) |
| 222 | x = (1000003*x) ^ *p++; |
| 223 | x ^= self->b_size; |
| 224 | if (x == -1) |
| 225 | x = -2; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 226 | self->b_hash = x; |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 227 | return x; |
| 228 | } |
| 229 | |
| 230 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 231 | buffer_str(PyBufferObject *self) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 232 | { |
| 233 | return PyString_FromStringAndSize(self->b_ptr, self->b_size); |
| 234 | } |
| 235 | |
| 236 | /* Sequence methods */ |
| 237 | |
| 238 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 239 | buffer_length(PyBufferObject *self) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 240 | { |
| 241 | return self->b_size; |
| 242 | } |
| 243 | |
| 244 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 245 | buffer_concat(PyBufferObject *self, PyObject *other) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 246 | { |
| 247 | PyBufferProcs *pb = other->ob_type->tp_as_buffer; |
| 248 | char *p1; |
| 249 | void *p2; |
| 250 | PyObject *ob; |
| 251 | int count; |
| 252 | |
| 253 | if ( pb == NULL || |
| 254 | pb->bf_getreadbuffer == NULL || |
| 255 | pb->bf_getsegcount == NULL ) |
| 256 | { |
| 257 | PyErr_BadArgument(); |
| 258 | return NULL; |
| 259 | } |
| 260 | if ( (*pb->bf_getsegcount)(other, NULL) != 1 ) |
| 261 | { |
| 262 | /* ### use a different exception type/message? */ |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 263 | PyErr_SetString(PyExc_TypeError, |
| 264 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 265 | return NULL; |
| 266 | } |
| 267 | |
| 268 | /* optimize special case */ |
| 269 | if ( self->b_size == 0 ) |
| 270 | { |
| 271 | Py_INCREF(other); |
| 272 | return other; |
| 273 | } |
| 274 | |
| 275 | if ( (count = (*pb->bf_getreadbuffer)(other, 0, &p2)) < 0 ) |
| 276 | return NULL; |
| 277 | |
| 278 | /* optimize special case */ |
| 279 | if ( count == 0 ) |
| 280 | { |
| 281 | Py_INCREF(self); |
| 282 | return (PyObject *)self; |
| 283 | } |
| 284 | |
| 285 | ob = PyString_FromStringAndSize(NULL, self->b_size + count); |
| 286 | p1 = PyString_AS_STRING(ob); |
| 287 | memcpy(p1, self->b_ptr, self->b_size); |
| 288 | memcpy(p1 + self->b_size, p2, count); |
| 289 | |
| 290 | /* there is an extra byte in the string object, so this is safe */ |
| 291 | p1[self->b_size + count] = '\0'; |
| 292 | |
| 293 | return ob; |
| 294 | } |
| 295 | |
| 296 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 297 | buffer_repeat(PyBufferObject *self, int count) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 298 | { |
| 299 | PyObject *ob; |
| 300 | register char *p; |
| 301 | void *ptr = self->b_ptr; |
| 302 | int size = self->b_size; |
| 303 | |
| 304 | if ( count < 0 ) |
| 305 | count = 0; |
| 306 | ob = PyString_FromStringAndSize(NULL, size * count); |
| 307 | if ( ob == NULL ) |
| 308 | return NULL; |
| 309 | |
| 310 | p = PyString_AS_STRING(ob); |
| 311 | while ( count-- ) |
| 312 | { |
| 313 | memcpy(p, ptr, size); |
| 314 | p += size; |
| 315 | } |
| 316 | |
| 317 | /* there is an extra byte in the string object, so this is safe */ |
| 318 | *p = '\0'; |
| 319 | |
| 320 | return ob; |
| 321 | } |
| 322 | |
| 323 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 324 | buffer_item(PyBufferObject *self, int idx) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 325 | { |
| 326 | if ( idx < 0 || idx >= self->b_size ) |
| 327 | { |
| 328 | PyErr_SetString(PyExc_IndexError, "buffer index out of range"); |
| 329 | return NULL; |
| 330 | } |
| 331 | return PyString_FromStringAndSize((char *)self->b_ptr + idx, 1); |
| 332 | } |
| 333 | |
| 334 | static PyObject * |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 335 | buffer_slice(PyBufferObject *self, int left, int right) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 336 | { |
| 337 | if ( left < 0 ) |
| 338 | left = 0; |
| 339 | if ( right < 0 ) |
| 340 | right = 0; |
| 341 | if ( right > self->b_size ) |
| 342 | right = self->b_size; |
| 343 | if ( left == 0 && right == self->b_size ) |
| 344 | { |
| 345 | /* same as self */ |
| 346 | Py_INCREF(self); |
| 347 | return (PyObject *)self; |
| 348 | } |
| 349 | if ( right < left ) |
| 350 | right = left; |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 351 | return PyString_FromStringAndSize((char *)self->b_ptr + left, |
| 352 | right - left); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 353 | } |
| 354 | |
| 355 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 356 | buffer_ass_item(PyBufferObject *self, int idx, PyObject *other) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 357 | { |
| 358 | PyBufferProcs *pb; |
| 359 | void *p; |
| 360 | int count; |
| 361 | |
| 362 | if ( self->b_readonly ) { |
| 363 | PyErr_SetString(PyExc_TypeError, |
| 364 | "buffer is read-only"); |
| 365 | return -1; |
| 366 | } |
| 367 | |
| 368 | if (idx < 0 || idx >= self->b_size) { |
| 369 | PyErr_SetString(PyExc_IndexError, |
| 370 | "buffer assignment index out of range"); |
| 371 | return -1; |
| 372 | } |
| 373 | |
| 374 | pb = other ? other->ob_type->tp_as_buffer : NULL; |
| 375 | if ( pb == NULL || |
| 376 | pb->bf_getreadbuffer == NULL || |
| 377 | pb->bf_getsegcount == NULL ) |
| 378 | { |
| 379 | PyErr_BadArgument(); |
| 380 | return -1; |
| 381 | } |
| 382 | if ( (*pb->bf_getsegcount)(other, NULL) != 1 ) |
| 383 | { |
| 384 | /* ### use a different exception type/message? */ |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 385 | PyErr_SetString(PyExc_TypeError, |
| 386 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 387 | return -1; |
| 388 | } |
| 389 | |
| 390 | if ( (count = (*pb->bf_getreadbuffer)(other, 0, &p)) < 0 ) |
| 391 | return -1; |
| 392 | if ( count != 1 ) { |
| 393 | PyErr_SetString(PyExc_TypeError, |
| 394 | "right operand must be a single byte"); |
| 395 | return -1; |
| 396 | } |
| 397 | |
| 398 | ((char *)self->b_ptr)[idx] = *(char *)p; |
| 399 | return 0; |
| 400 | } |
| 401 | |
| 402 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 403 | buffer_ass_slice(PyBufferObject *self, int left, int right, PyObject *other) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 404 | { |
| 405 | PyBufferProcs *pb; |
| 406 | void *p; |
| 407 | int slice_len; |
| 408 | int count; |
| 409 | |
| 410 | if ( self->b_readonly ) { |
| 411 | PyErr_SetString(PyExc_TypeError, |
| 412 | "buffer is read-only"); |
| 413 | return -1; |
| 414 | } |
| 415 | |
| 416 | pb = other ? other->ob_type->tp_as_buffer : NULL; |
| 417 | if ( pb == NULL || |
| 418 | pb->bf_getreadbuffer == NULL || |
| 419 | pb->bf_getsegcount == NULL ) |
| 420 | { |
| 421 | PyErr_BadArgument(); |
| 422 | return -1; |
| 423 | } |
| 424 | if ( (*pb->bf_getsegcount)(other, NULL) != 1 ) |
| 425 | { |
| 426 | /* ### use a different exception type/message? */ |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 427 | PyErr_SetString(PyExc_TypeError, |
| 428 | "single-segment buffer object expected"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 429 | return -1; |
| 430 | } |
| 431 | if ( (count = (*pb->bf_getreadbuffer)(other, 0, &p)) < 0 ) |
| 432 | return -1; |
| 433 | |
| 434 | if ( left < 0 ) |
| 435 | left = 0; |
| 436 | else if ( left > self->b_size ) |
| 437 | left = self->b_size; |
| 438 | if ( right < left ) |
| 439 | right = left; |
| 440 | else if ( right > self->b_size ) |
| 441 | right = self->b_size; |
| 442 | slice_len = right - left; |
| 443 | |
| 444 | if ( count != slice_len ) { |
Guido van Rossum | cd037e7 | 1999-03-24 19:05:31 +0000 | [diff] [blame] | 445 | PyErr_SetString( |
| 446 | PyExc_TypeError, |
| 447 | "right operand length must match slice length"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 448 | return -1; |
| 449 | } |
| 450 | |
| 451 | if ( slice_len ) |
| 452 | memcpy((char *)self->b_ptr + left, p, slice_len); |
| 453 | |
| 454 | return 0; |
| 455 | } |
| 456 | |
| 457 | /* Buffer methods */ |
| 458 | |
| 459 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 460 | buffer_getreadbuf(PyBufferObject *self, int idx, void **pp) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 461 | { |
| 462 | if ( idx != 0 ) { |
| 463 | PyErr_SetString(PyExc_SystemError, |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 464 | "accessing non-existent buffer segment"); |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 465 | return -1; |
| 466 | } |
| 467 | *pp = self->b_ptr; |
| 468 | return self->b_size; |
| 469 | } |
| 470 | |
| 471 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 472 | buffer_getwritebuf(PyBufferObject *self, int idx, void **pp) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 473 | { |
| 474 | if ( self->b_readonly ) |
| 475 | { |
| 476 | PyErr_SetString(PyExc_TypeError, "buffer is read-only"); |
| 477 | return -1; |
| 478 | } |
| 479 | return buffer_getreadbuf(self, idx, pp); |
| 480 | } |
| 481 | |
| 482 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 483 | buffer_getsegcount(PyBufferObject *self, int *lenp) |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 484 | { |
| 485 | if ( lenp ) |
| 486 | *lenp = self->b_size; |
| 487 | return 1; |
| 488 | } |
| 489 | |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 490 | static int |
Fred Drake | 7991247 | 2000-07-09 04:06:11 +0000 | [diff] [blame] | 491 | buffer_getcharbuf(PyBufferObject *self, int idx, const char **pp) |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 492 | { |
| 493 | if ( idx != 0 ) { |
| 494 | PyErr_SetString(PyExc_SystemError, |
| 495 | "accessing non-existent buffer segment"); |
| 496 | return -1; |
| 497 | } |
| 498 | *pp = (const char *)self->b_ptr; |
| 499 | return self->b_size; |
| 500 | } |
| 501 | |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 502 | |
| 503 | static PySequenceMethods buffer_as_sequence = { |
| 504 | (inquiry)buffer_length, /*sq_length*/ |
| 505 | (binaryfunc)buffer_concat, /*sq_concat*/ |
| 506 | (intargfunc)buffer_repeat, /*sq_repeat*/ |
| 507 | (intargfunc)buffer_item, /*sq_item*/ |
| 508 | (intintargfunc)buffer_slice, /*sq_slice*/ |
| 509 | (intobjargproc)buffer_ass_item, /*sq_ass_item*/ |
| 510 | (intintobjargproc)buffer_ass_slice, /*sq_ass_slice*/ |
| 511 | }; |
| 512 | |
| 513 | static PyBufferProcs buffer_as_buffer = { |
| 514 | (getreadbufferproc)buffer_getreadbuf, |
| 515 | (getwritebufferproc)buffer_getwritebuf, |
| 516 | (getsegcountproc)buffer_getsegcount, |
Guido van Rossum | 1db7070 | 1998-10-08 02:18:52 +0000 | [diff] [blame] | 517 | (getcharbufferproc)buffer_getcharbuf, |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 518 | }; |
| 519 | |
| 520 | PyTypeObject PyBuffer_Type = { |
| 521 | PyObject_HEAD_INIT(&PyType_Type) |
| 522 | 0, |
| 523 | "buffer", |
| 524 | sizeof(PyBufferObject), |
| 525 | 0, |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 526 | (destructor)buffer_dealloc, /* tp_dealloc */ |
| 527 | 0, /* tp_print */ |
| 528 | 0, /* tp_getattr */ |
| 529 | 0, /* tp_setattr */ |
| 530 | (cmpfunc)buffer_compare, /* tp_compare */ |
| 531 | (reprfunc)buffer_repr, /* tp_repr */ |
| 532 | 0, /* tp_as_number */ |
| 533 | &buffer_as_sequence, /* tp_as_sequence */ |
| 534 | 0, /* tp_as_mapping */ |
| 535 | (hashfunc)buffer_hash, /* tp_hash */ |
| 536 | 0, /* tp_call */ |
| 537 | (reprfunc)buffer_str, /* tp_str */ |
| 538 | PyObject_GenericGetAttr, /* tp_getattro */ |
| 539 | 0, /* tp_setattro */ |
| 540 | &buffer_as_buffer, /* tp_as_buffer */ |
| 541 | Py_TPFLAGS_DEFAULT, /* tp_flags */ |
| 542 | 0, /* tp_doc */ |
Guido van Rossum | 2e19bd7 | 1998-10-07 14:36:10 +0000 | [diff] [blame] | 543 | }; |