Mon, 25 Jul 2022 15:34:19 +0200
#170 test cxBufferGet
universe@483 | 1 | /* |
universe@483 | 2 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. |
universe@483 | 3 | * |
universe@483 | 4 | * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved. |
universe@483 | 5 | * |
universe@483 | 6 | * Redistribution and use in source and binary forms, with or without |
universe@483 | 7 | * modification, are permitted provided that the following conditions are met: |
universe@483 | 8 | * |
universe@483 | 9 | * 1. Redistributions of source code must retain the above copyright |
universe@483 | 10 | * notice, this list of conditions and the following disclaimer. |
universe@483 | 11 | * |
universe@483 | 12 | * 2. Redistributions in binary form must reproduce the above copyright |
universe@483 | 13 | * notice, this list of conditions and the following disclaimer in the |
universe@483 | 14 | * documentation and/or other materials provided with the distribution. |
universe@483 | 15 | * |
universe@483 | 16 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
universe@483 | 17 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
universe@483 | 18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
universe@483 | 19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
universe@483 | 20 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
universe@483 | 21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
universe@483 | 22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
universe@483 | 23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
universe@483 | 24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
universe@483 | 25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
universe@483 | 26 | * POSSIBILITY OF SUCH DAMAGE. |
universe@483 | 27 | */ |
universe@483 | 28 | |
universe@483 | 29 | #include "cx/buffer.h" |
universe@483 | 30 | #include "cx/utils.h" |
universe@483 | 31 | |
universe@483 | 32 | #include <stdlib.h> |
universe@530 | 33 | #include <stdio.h> |
universe@483 | 34 | #include <string.h> |
universe@539 | 35 | #include <stdint.h> |
universe@483 | 36 | |
universe@501 | 37 | int cxBufferInit( |
universe@501 | 38 | CxBuffer *buffer, |
universe@483 | 39 | void *space, |
universe@483 | 40 | size_t capacity, |
universe@529 | 41 | CxAllocator const *allocator, |
universe@483 | 42 | int flags |
universe@483 | 43 | ) { |
universe@501 | 44 | buffer->allocator = allocator; |
universe@501 | 45 | buffer->flags = flags; |
universe@501 | 46 | if (!space) { |
universe@501 | 47 | buffer->bytes = cxMalloc(allocator, capacity); |
universe@501 | 48 | if (buffer->bytes == NULL) { |
universe@501 | 49 | return 1; |
universe@483 | 50 | } |
universe@501 | 51 | buffer->flags |= CX_BUFFER_FREE_CONTENTS; |
universe@501 | 52 | } else { |
universe@501 | 53 | buffer->bytes = space; |
universe@501 | 54 | } |
universe@501 | 55 | buffer->capacity = capacity; |
universe@501 | 56 | buffer->size = 0; |
universe@539 | 57 | buffer->pos = 0; |
universe@483 | 58 | |
universe@539 | 59 | buffer->flush_func = NULL; |
universe@541 | 60 | buffer->flush_target = NULL; |
universe@539 | 61 | buffer->flush_blkmax = 0; |
universe@539 | 62 | buffer->flush_blksize = 4096; |
universe@539 | 63 | buffer->flush_threshold = SIZE_MAX; |
universe@483 | 64 | |
universe@501 | 65 | return 0; |
universe@483 | 66 | } |
universe@483 | 67 | |
universe@500 | 68 | void cxBufferDestroy(CxBuffer *buffer) { |
universe@483 | 69 | if ((buffer->flags & CX_BUFFER_FREE_CONTENTS) == CX_BUFFER_FREE_CONTENTS) { |
universe@501 | 70 | cxFree(buffer->allocator, buffer->bytes); |
universe@483 | 71 | } |
universe@483 | 72 | } |
universe@483 | 73 | |
universe@483 | 74 | int cxBufferSeek( |
universe@500 | 75 | CxBuffer *buffer, |
universe@483 | 76 | off_t offset, |
universe@483 | 77 | int whence |
universe@483 | 78 | ) { |
universe@483 | 79 | size_t npos; |
universe@483 | 80 | switch (whence) { |
universe@483 | 81 | case SEEK_CUR: |
universe@483 | 82 | npos = buffer->pos; |
universe@483 | 83 | break; |
universe@483 | 84 | case SEEK_END: |
universe@483 | 85 | npos = buffer->size; |
universe@483 | 86 | break; |
universe@483 | 87 | case SEEK_SET: |
universe@483 | 88 | npos = 0; |
universe@483 | 89 | break; |
universe@483 | 90 | default: |
universe@483 | 91 | return -1; |
universe@483 | 92 | } |
universe@483 | 93 | |
universe@483 | 94 | size_t opos = npos; |
universe@483 | 95 | npos += offset; |
universe@483 | 96 | |
universe@483 | 97 | if ((offset > 0 && npos < opos) || (offset < 0 && npos > opos)) { |
universe@483 | 98 | return -1; |
universe@483 | 99 | } |
universe@483 | 100 | |
universe@483 | 101 | if (npos >= buffer->size) { |
universe@483 | 102 | return -1; |
universe@483 | 103 | } else { |
universe@483 | 104 | buffer->pos = npos; |
universe@483 | 105 | return 0; |
universe@483 | 106 | } |
universe@483 | 107 | |
universe@483 | 108 | } |
universe@483 | 109 | |
universe@529 | 110 | void cxBufferClear(CxBuffer *buffer) { |
universe@529 | 111 | memset(buffer->bytes, 0, buffer->size); |
universe@529 | 112 | buffer->size = 0; |
universe@529 | 113 | buffer->pos = 0; |
universe@529 | 114 | } |
universe@529 | 115 | |
universe@529 | 116 | int cxBufferEof(CxBuffer const *buffer) { |
universe@483 | 117 | return buffer->pos >= buffer->size; |
universe@483 | 118 | } |
universe@483 | 119 | |
universe@483 | 120 | int cxBufferMinimumCapacity( |
universe@500 | 121 | CxBuffer *buffer, |
universe@532 | 122 | size_t newcap |
universe@483 | 123 | ) { |
universe@532 | 124 | if (newcap <= buffer->capacity) { |
universe@532 | 125 | return 0; |
universe@483 | 126 | } |
universe@483 | 127 | |
universe@536 | 128 | if (cxReallocate(buffer->allocator, |
universe@536 | 129 | (void **) &buffer->bytes, newcap) == 0) { |
universe@483 | 130 | buffer->capacity = newcap; |
universe@533 | 131 | return 0; |
universe@483 | 132 | } else { |
universe@483 | 133 | return -1; |
universe@483 | 134 | } |
universe@483 | 135 | } |
universe@483 | 136 | |
universe@544 | 137 | /** |
universe@544 | 138 | * Helps flushing data to the flush target of a buffer. |
universe@544 | 139 | * |
universe@544 | 140 | * @param buffer the buffer containing the config |
universe@544 | 141 | * @param space the data to flush |
universe@544 | 142 | * @param size the element size |
universe@544 | 143 | * @param nitems the number of items |
universe@544 | 144 | * @return the number of items flushed |
universe@544 | 145 | */ |
universe@544 | 146 | static size_t cx_buffer_write_flush_helper( |
universe@544 | 147 | CxBuffer *buffer, |
universe@544 | 148 | unsigned char const *space, |
universe@544 | 149 | size_t size, |
universe@544 | 150 | size_t nitems |
universe@544 | 151 | ) { |
universe@544 | 152 | size_t pos = 0; |
universe@544 | 153 | size_t remaining = nitems; |
universe@544 | 154 | size_t max_items = buffer->flush_blksize / size; |
universe@544 | 155 | while (remaining > 0) { |
universe@544 | 156 | size_t items = remaining > max_items ? max_items : remaining; |
universe@544 | 157 | size_t flushed = buffer->flush_func( |
universe@544 | 158 | space + pos, |
universe@544 | 159 | size, items, |
universe@544 | 160 | buffer->flush_target); |
universe@544 | 161 | if (flushed > 0) { |
universe@544 | 162 | pos += (flushed * size); |
universe@544 | 163 | remaining -= flushed; |
universe@544 | 164 | } else { |
universe@544 | 165 | // if no bytes can be flushed out anymore, we give up |
universe@544 | 166 | break; |
universe@544 | 167 | } |
universe@544 | 168 | } |
universe@544 | 169 | return nitems - remaining; |
universe@544 | 170 | } |
universe@544 | 171 | |
universe@483 | 172 | size_t cxBufferWrite( |
universe@489 | 173 | void const *ptr, |
universe@483 | 174 | size_t size, |
universe@483 | 175 | size_t nitems, |
universe@500 | 176 | CxBuffer *buffer |
universe@483 | 177 | ) { |
universe@543 | 178 | // optimize for easy case |
universe@543 | 179 | if (size == 1 && (buffer->capacity - buffer->pos) >= nitems) { |
universe@543 | 180 | memcpy(buffer->bytes + buffer->pos, ptr, nitems); |
universe@543 | 181 | buffer->pos += nitems; |
universe@543 | 182 | if (buffer->pos > buffer->size) { |
universe@543 | 183 | buffer->size = buffer->pos; |
universe@543 | 184 | } |
universe@543 | 185 | return nitems; |
universe@543 | 186 | } |
universe@543 | 187 | |
universe@483 | 188 | size_t len; |
universe@544 | 189 | size_t nitems_out = nitems; |
universe@483 | 190 | if (cx_szmul(size, nitems, &len)) { |
universe@483 | 191 | return 0; |
universe@483 | 192 | } |
universe@483 | 193 | size_t required = buffer->pos + len; |
universe@483 | 194 | if (buffer->pos > required) { |
universe@483 | 195 | return 0; |
universe@483 | 196 | } |
universe@483 | 197 | |
universe@539 | 198 | bool perform_flush = false; |
universe@483 | 199 | if (required > buffer->capacity) { |
universe@539 | 200 | if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND && required) { |
universe@539 | 201 | if (buffer->flush_blkmax > 0 && required > buffer->flush_threshold) { |
universe@539 | 202 | perform_flush = true; |
universe@539 | 203 | } else { |
universe@539 | 204 | if (cxBufferMinimumCapacity(buffer, required)) { |
universe@539 | 205 | return 0; |
universe@539 | 206 | } |
universe@483 | 207 | } |
universe@483 | 208 | } else { |
universe@539 | 209 | if (buffer->flush_blkmax > 0) { |
universe@539 | 210 | perform_flush = true; |
universe@539 | 211 | } else { |
universe@539 | 212 | // truncate data to be written, if we can neither extend nor flush |
universe@539 | 213 | len = buffer->capacity - buffer->pos; |
universe@539 | 214 | if (size > 1) { |
universe@539 | 215 | len -= len % size; |
universe@539 | 216 | } |
universe@544 | 217 | nitems_out = len / size; |
universe@483 | 218 | } |
universe@483 | 219 | } |
universe@483 | 220 | } |
universe@483 | 221 | |
universe@483 | 222 | if (len == 0) { |
universe@483 | 223 | return len; |
universe@483 | 224 | } |
universe@483 | 225 | |
universe@539 | 226 | if (perform_flush) { |
universe@544 | 227 | size_t flush_max; |
universe@544 | 228 | if (cx_szmul(buffer->flush_blkmax, buffer->flush_blksize, &flush_max)) { |
universe@544 | 229 | return 0; |
universe@544 | 230 | } |
universe@544 | 231 | size_t flush_pos = buffer->flush_func == NULL || buffer->flush_target == NULL |
universe@544 | 232 | ? buffer->pos |
universe@544 | 233 | : cx_buffer_write_flush_helper(buffer, buffer->bytes, 1, buffer->pos); |
universe@544 | 234 | if (flush_pos == buffer->pos) { |
universe@544 | 235 | // entire buffer has been flushed, we can reset |
universe@544 | 236 | buffer->size = buffer->pos = 0; |
universe@544 | 237 | |
universe@544 | 238 | size_t items_flush; // how many items can also be directly flushed |
universe@544 | 239 | size_t items_keep; // how many items have to be written to the buffer |
universe@544 | 240 | |
universe@544 | 241 | items_flush = flush_max >= required ? nitems : (flush_max - flush_pos) / size; |
universe@544 | 242 | if (items_flush > 0) { |
universe@544 | 243 | items_flush = cx_buffer_write_flush_helper(buffer, ptr, size, items_flush / size); |
universe@544 | 244 | // in case we could not flush everything, keep the rest |
universe@544 | 245 | } |
universe@544 | 246 | items_keep = nitems - items_flush; |
universe@544 | 247 | if (items_keep > 0) { |
universe@544 | 248 | // try again with the remaining stuff |
universe@544 | 249 | unsigned char const *new_ptr = ptr; |
universe@544 | 250 | new_ptr += items_flush * size; |
universe@567 | 251 | // report the directly flushed items as written plus the remaining stuff |
universe@567 | 252 | return items_flush + cxBufferWrite(new_ptr, size, items_keep, buffer); |
universe@544 | 253 | } else { |
universe@544 | 254 | // all items have been flushed - report them as written |
universe@544 | 255 | return nitems; |
universe@544 | 256 | } |
universe@544 | 257 | } else if (flush_pos == 0) { |
universe@544 | 258 | // nothing could be flushed at all, we immediately give up without writing any data |
universe@544 | 259 | return 0; |
universe@544 | 260 | } else { |
universe@567 | 261 | // we were partially successful, we shift left and try again |
universe@544 | 262 | cxBufferShiftLeft(buffer, flush_pos); |
universe@544 | 263 | return cxBufferWrite(ptr, size, nitems, buffer); |
universe@544 | 264 | } |
universe@539 | 265 | } else { |
universe@539 | 266 | memcpy(buffer->bytes + buffer->pos, ptr, len); |
universe@539 | 267 | buffer->pos += len; |
universe@539 | 268 | if (buffer->pos > buffer->size) { |
universe@539 | 269 | buffer->size = buffer->pos; |
universe@539 | 270 | } |
universe@544 | 271 | return nitems_out; |
universe@483 | 272 | } |
universe@483 | 273 | |
universe@483 | 274 | } |
universe@483 | 275 | |
universe@538 | 276 | int cxBufferPut( |
universe@538 | 277 | CxBuffer *buffer, |
universe@538 | 278 | int c |
universe@538 | 279 | ) { |
universe@538 | 280 | c &= 0xFF; |
universe@538 | 281 | unsigned char const ch = c; |
universe@538 | 282 | if (cxBufferWrite(&ch, 1, 1, buffer) == 1) { |
universe@538 | 283 | return c; |
universe@538 | 284 | } else { |
universe@538 | 285 | return EOF; |
universe@538 | 286 | } |
universe@538 | 287 | } |
universe@538 | 288 | |
universe@538 | 289 | size_t cxBufferPutString( |
universe@538 | 290 | CxBuffer *buffer, |
universe@538 | 291 | const char *str |
universe@538 | 292 | ) { |
universe@538 | 293 | return cxBufferWrite(str, 1, strlen(str), buffer); |
universe@538 | 294 | } |
universe@538 | 295 | |
universe@483 | 296 | size_t cxBufferRead( |
universe@483 | 297 | void *ptr, |
universe@483 | 298 | size_t size, |
universe@483 | 299 | size_t nitems, |
universe@500 | 300 | CxBuffer *buffer |
universe@483 | 301 | ) { |
universe@483 | 302 | size_t len; |
universe@483 | 303 | if (cx_szmul(size, nitems, &len)) { |
universe@483 | 304 | return 0; |
universe@483 | 305 | } |
universe@483 | 306 | if (buffer->pos + len > buffer->size) { |
universe@483 | 307 | len = buffer->size - buffer->pos; |
universe@483 | 308 | if (size > 1) len -= len % size; |
universe@483 | 309 | } |
universe@483 | 310 | |
universe@483 | 311 | if (len <= 0) { |
universe@483 | 312 | return len; |
universe@483 | 313 | } |
universe@483 | 314 | |
universe@483 | 315 | memcpy(ptr, buffer->bytes + buffer->pos, len); |
universe@483 | 316 | buffer->pos += len; |
universe@483 | 317 | |
universe@483 | 318 | return len / size; |
universe@483 | 319 | } |
universe@483 | 320 | |
universe@500 | 321 | int cxBufferGet(CxBuffer *buffer) { |
universe@483 | 322 | if (cxBufferEof(buffer)) { |
universe@483 | 323 | return EOF; |
universe@483 | 324 | } else { |
universe@483 | 325 | int c = buffer->bytes[buffer->pos]; |
universe@483 | 326 | buffer->pos++; |
universe@483 | 327 | return c; |
universe@483 | 328 | } |
universe@483 | 329 | } |
universe@483 | 330 | |
universe@483 | 331 | int cxBufferShiftLeft( |
universe@500 | 332 | CxBuffer *buffer, |
universe@483 | 333 | size_t shift |
universe@483 | 334 | ) { |
universe@483 | 335 | if (shift >= buffer->size) { |
universe@483 | 336 | buffer->pos = buffer->size = 0; |
universe@483 | 337 | } else { |
universe@483 | 338 | memmove(buffer->bytes, buffer->bytes + shift, buffer->size - shift); |
universe@483 | 339 | buffer->size -= shift; |
universe@483 | 340 | |
universe@483 | 341 | if (buffer->pos >= shift) { |
universe@483 | 342 | buffer->pos -= shift; |
universe@483 | 343 | } else { |
universe@483 | 344 | buffer->pos = 0; |
universe@483 | 345 | } |
universe@483 | 346 | } |
universe@483 | 347 | return 0; |
universe@483 | 348 | } |
universe@483 | 349 | |
universe@483 | 350 | int cxBufferShiftRight( |
universe@500 | 351 | CxBuffer *buffer, |
universe@483 | 352 | size_t shift |
universe@483 | 353 | ) { |
universe@483 | 354 | size_t req_capacity = buffer->size + shift; |
universe@483 | 355 | size_t movebytes; |
universe@483 | 356 | |
universe@483 | 357 | // auto extend buffer, if required and enabled |
universe@483 | 358 | if (buffer->capacity < req_capacity) { |
universe@483 | 359 | if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) { |
universe@483 | 360 | if (cxBufferMinimumCapacity(buffer, req_capacity)) { |
universe@483 | 361 | return 1; |
universe@483 | 362 | } |
universe@483 | 363 | movebytes = buffer->size; |
universe@483 | 364 | } else { |
universe@483 | 365 | movebytes = buffer->capacity - shift; |
universe@483 | 366 | } |
universe@483 | 367 | } else { |
universe@483 | 368 | movebytes = buffer->size; |
universe@483 | 369 | } |
universe@483 | 370 | |
universe@483 | 371 | memmove(buffer->bytes + shift, buffer->bytes, movebytes); |
universe@483 | 372 | buffer->size = shift + movebytes; |
universe@483 | 373 | |
universe@483 | 374 | buffer->pos += shift; |
universe@483 | 375 | if (buffer->pos > buffer->size) { |
universe@483 | 376 | buffer->pos = buffer->size; |
universe@483 | 377 | } |
universe@483 | 378 | |
universe@483 | 379 | return 0; |
universe@483 | 380 | } |
universe@483 | 381 | |
universe@483 | 382 | int cxBufferShift( |
universe@500 | 383 | CxBuffer *buffer, |
universe@483 | 384 | off_t shift |
universe@483 | 385 | ) { |
universe@483 | 386 | if (shift < 0) { |
universe@483 | 387 | return cxBufferShiftLeft(buffer, (size_t) (-shift)); |
universe@483 | 388 | } else if (shift > 0) { |
universe@483 | 389 | return cxBufferShiftRight(buffer, (size_t) shift); |
universe@483 | 390 | } else { |
universe@483 | 391 | return 0; |
universe@483 | 392 | } |
universe@483 | 393 | } |