comparison: src/buffer.c
src/buffer.c
- changeset 1028
- 3e4905241838
- parent 1024
- 8f99f6c28bd3
- child 1030
- 06091e067bee
equal
deleted
inserted
replaced
| 1027:b1373253e202 | 1028:3e4905241838 |
|---|---|
| 29 #include "cx/buffer.h" | 29 #include "cx/buffer.h" |
| 30 | 30 |
| 31 #include <stdio.h> | 31 #include <stdio.h> |
| 32 #include <string.h> | 32 #include <string.h> |
| 33 | 33 |
| 34 static int buffer_copy_on_write(CxBuffer* buffer, size_t newcap) { | 34 static int buffer_copy_on_write(CxBuffer* buffer) { |
| 35 if (0 == (buffer->flags & CX_BUFFER_COPY_ON_WRITE)) return 0; | 35 if (0 == (buffer->flags & CX_BUFFER_COPY_ON_WRITE)) return 0; |
| 36 if (newcap == 0) newcap = buffer->capacity; | 36 void *newspace = cxMalloc(buffer->allocator, buffer->capacity); |
| 37 void *newspace = cxMalloc(buffer->allocator, newcap); | |
| 38 if (NULL == newspace) return -1; | 37 if (NULL == newspace) return -1; |
| 39 memcpy(newspace, buffer->space, buffer->size); | 38 memcpy(newspace, buffer->space, buffer->size); |
| 40 buffer->space = newspace; | 39 buffer->space = newspace; |
| 41 buffer->capacity = newcap; | |
| 42 buffer->flags &= ~CX_BUFFER_COPY_ON_WRITE; | 40 buffer->flags &= ~CX_BUFFER_COPY_ON_WRITE; |
| 43 buffer->flags |= CX_BUFFER_FREE_CONTENTS; | 41 buffer->flags |= CX_BUFFER_FREE_CONTENTS; |
| 44 return 0; | 42 return 0; |
| 45 } | 43 } |
| 46 | 44 |
| 51 const CxAllocator *allocator, | 49 const CxAllocator *allocator, |
| 52 int flags | 50 int flags |
| 53 ) { | 51 ) { |
| 54 if (allocator == NULL) { | 52 if (allocator == NULL) { |
| 55 allocator = cxDefaultAllocator; | 53 allocator = cxDefaultAllocator; |
| 54 } | |
| 55 if (flags & CX_BUFFER_COPY_ON_EXTEND) { | |
| 56 flags |= CX_BUFFER_AUTO_EXTEND; | |
| 56 } | 57 } |
| 57 buffer->allocator = allocator; | 58 buffer->allocator = allocator; |
| 58 buffer->flags = flags; | 59 buffer->flags = flags; |
| 59 if (!space) { | 60 if (!space) { |
| 60 buffer->bytes = cxMalloc(allocator, capacity); | 61 buffer->bytes = cxMalloc(allocator, capacity); |
| 168 ) { | 169 ) { |
| 169 if (newcap <= buffer->capacity) { | 170 if (newcap <= buffer->capacity) { |
| 170 return 0; | 171 return 0; |
| 171 } | 172 } |
| 172 | 173 |
| 173 if (buffer->flags & CX_BUFFER_COPY_ON_WRITE) { | 174 const int force_copy_flags = CX_BUFFER_COPY_ON_WRITE | CX_BUFFER_COPY_ON_EXTEND; |
| 174 return buffer_copy_on_write(buffer, newcap); | 175 if (buffer->flags & force_copy_flags) { |
| 176 void *newspace = cxMalloc(buffer->allocator, newcap); | |
| 177 if (NULL == newspace) return -1; | |
| 178 memcpy(newspace, buffer->space, buffer->size); | |
| 179 buffer->space = newspace; | |
| 180 buffer->capacity = newcap; | |
| 181 buffer->flags &= ~force_copy_flags; | |
| 182 buffer->flags |= CX_BUFFER_FREE_CONTENTS; | |
| 183 return 0; | |
| 175 } else if (cxReallocate(buffer->allocator, | 184 } else if (cxReallocate(buffer->allocator, |
| 176 (void **) &buffer->bytes, newcap) == 0) { | 185 (void **) &buffer->bytes, newcap) == 0) { |
| 177 buffer->capacity = newcap; | 186 buffer->capacity = newcap; |
| 178 return 0; | 187 return 0; |
| 179 } else { | 188 } else { |
| 222 size_t nitems, | 231 size_t nitems, |
| 223 CxBuffer *buffer | 232 CxBuffer *buffer |
| 224 ) { | 233 ) { |
| 225 // optimize for easy case | 234 // optimize for easy case |
| 226 if (size == 1 && (buffer->capacity - buffer->pos) >= nitems) { | 235 if (size == 1 && (buffer->capacity - buffer->pos) >= nitems) { |
| 227 if (buffer_copy_on_write(buffer, 0)) return 0; | 236 if (buffer_copy_on_write(buffer)) return 0; |
| 228 memcpy(buffer->bytes + buffer->pos, ptr, nitems); | 237 memcpy(buffer->bytes + buffer->pos, ptr, nitems); |
| 229 buffer->pos += nitems; | 238 buffer->pos += nitems; |
| 230 if (buffer->pos > buffer->size) { | 239 if (buffer->pos > buffer->size) { |
| 231 buffer->size = buffer->pos; | 240 buffer->size = buffer->pos; |
| 232 } | 241 } |
| 309 // we were partially successful, we shift left and try again | 318 // we were partially successful, we shift left and try again |
| 310 cxBufferShiftLeft(buffer, flush_pos); | 319 cxBufferShiftLeft(buffer, flush_pos); |
| 311 return cxBufferWrite(ptr, size, nitems, buffer); | 320 return cxBufferWrite(ptr, size, nitems, buffer); |
| 312 } | 321 } |
| 313 } else { | 322 } else { |
| 314 if (buffer_copy_on_write(buffer, 0)) return 0; | 323 if (buffer_copy_on_write(buffer)) return 0; |
| 315 memcpy(buffer->bytes + buffer->pos, ptr, len); | 324 memcpy(buffer->bytes + buffer->pos, ptr, len); |
| 316 buffer->pos += len; | 325 buffer->pos += len; |
| 317 if (buffer->pos > buffer->size) { | 326 if (buffer->pos > buffer->size) { |
| 318 buffer->size = buffer->pos; | 327 buffer->size = buffer->pos; |
| 319 } | 328 } |
| 393 size_t shift | 402 size_t shift |
| 394 ) { | 403 ) { |
| 395 if (shift >= buffer->size) { | 404 if (shift >= buffer->size) { |
| 396 buffer->pos = buffer->size = 0; | 405 buffer->pos = buffer->size = 0; |
| 397 } else { | 406 } else { |
| 398 if (buffer_copy_on_write(buffer, 0)) return -1; | 407 if (buffer_copy_on_write(buffer)) return -1; |
| 399 memmove(buffer->bytes, buffer->bytes + shift, buffer->size - shift); | 408 memmove(buffer->bytes, buffer->bytes + shift, buffer->size - shift); |
| 400 buffer->size -= shift; | 409 buffer->size -= shift; |
| 401 | 410 |
| 402 if (buffer->pos >= shift) { | 411 if (buffer->pos >= shift) { |
| 403 buffer->pos -= shift; | 412 buffer->pos -= shift; |
| 428 } else { | 437 } else { |
| 429 movebytes = buffer->size; | 438 movebytes = buffer->size; |
| 430 } | 439 } |
| 431 | 440 |
| 432 if (movebytes > 0) { | 441 if (movebytes > 0) { |
| 433 if (buffer_copy_on_write(buffer, 0)) return -1; | 442 if (buffer_copy_on_write(buffer)) return -1; |
| 434 memmove(buffer->bytes + shift, buffer->bytes, movebytes); | 443 memmove(buffer->bytes + shift, buffer->bytes, movebytes); |
| 435 buffer->size = shift + movebytes; | 444 buffer->size = shift + movebytes; |
| 436 } | 445 } |
| 437 | 446 |
| 438 buffer->pos += shift; | 447 buffer->pos += shift; |
