src/buffer.c

Sun, 24 Apr 2022 17:44:52 +0200

author
Mike Becker <universe@uap-core.de>
date
Sun, 24 Apr 2022 17:44:52 +0200
changeset 534
0e893f84a7dd
parent 533
8d70ad8da899
child 536
cb9b9739055e
permissions
-rw-r--r--

fix cxBufferMinimumCapacity not using the allocator

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@483 35
universe@501 36 int cxBufferInit(
universe@501 37 CxBuffer *buffer,
universe@483 38 void *space,
universe@483 39 size_t capacity,
universe@529 40 CxAllocator const *allocator,
universe@483 41 int flags
universe@483 42 ) {
universe@501 43 buffer->allocator = allocator;
universe@501 44 buffer->flags = flags;
universe@501 45 if (!space) {
universe@501 46 buffer->bytes = cxMalloc(allocator, capacity);
universe@501 47 if (buffer->bytes == NULL) {
universe@501 48 return 1;
universe@483 49 }
universe@501 50 buffer->flags |= CX_BUFFER_FREE_CONTENTS;
universe@501 51 } else {
universe@501 52 buffer->bytes = space;
universe@501 53 }
universe@501 54 buffer->capacity = capacity;
universe@501 55 buffer->size = 0;
universe@483 56
universe@501 57 buffer->pos = 0;
universe@483 58
universe@501 59 return 0;
universe@483 60 }
universe@483 61
universe@500 62 void cxBufferDestroy(CxBuffer *buffer) {
universe@483 63 if ((buffer->flags & CX_BUFFER_FREE_CONTENTS) == CX_BUFFER_FREE_CONTENTS) {
universe@501 64 cxFree(buffer->allocator, buffer->bytes);
universe@483 65 }
universe@483 66 }
universe@483 67
universe@483 68 int cxBufferSeek(
universe@500 69 CxBuffer *buffer,
universe@483 70 off_t offset,
universe@483 71 int whence
universe@483 72 ) {
universe@483 73 size_t npos;
universe@483 74 switch (whence) {
universe@483 75 case SEEK_CUR:
universe@483 76 npos = buffer->pos;
universe@483 77 break;
universe@483 78 case SEEK_END:
universe@483 79 npos = buffer->size;
universe@483 80 break;
universe@483 81 case SEEK_SET:
universe@483 82 npos = 0;
universe@483 83 break;
universe@483 84 default:
universe@483 85 return -1;
universe@483 86 }
universe@483 87
universe@483 88 size_t opos = npos;
universe@483 89 npos += offset;
universe@483 90
universe@483 91 if ((offset > 0 && npos < opos) || (offset < 0 && npos > opos)) {
universe@483 92 return -1;
universe@483 93 }
universe@483 94
universe@483 95 if (npos >= buffer->size) {
universe@483 96 return -1;
universe@483 97 } else {
universe@483 98 buffer->pos = npos;
universe@483 99 return 0;
universe@483 100 }
universe@483 101
universe@483 102 }
universe@483 103
universe@529 104 void cxBufferClear(CxBuffer *buffer) {
universe@529 105 memset(buffer->bytes, 0, buffer->size);
universe@529 106 buffer->size = 0;
universe@529 107 buffer->pos = 0;
universe@529 108 }
universe@529 109
universe@529 110 int cxBufferEof(CxBuffer const *buffer) {
universe@483 111 return buffer->pos >= buffer->size;
universe@483 112 }
universe@483 113
universe@483 114 int cxBufferMinimumCapacity(
universe@500 115 CxBuffer *buffer,
universe@532 116 size_t newcap
universe@483 117 ) {
universe@532 118 if (newcap <= buffer->capacity) {
universe@532 119 return 0;
universe@483 120 }
universe@483 121
universe@534 122 if (cxReallocate(buffer->allocator, &buffer->bytes, newcap) == 0) {
universe@483 123 buffer->capacity = newcap;
universe@533 124 return 0;
universe@483 125 } else {
universe@483 126 return -1;
universe@483 127 }
universe@483 128 }
universe@483 129
universe@483 130 size_t cxBufferWrite(
universe@489 131 void const *ptr,
universe@483 132 size_t size,
universe@483 133 size_t nitems,
universe@500 134 CxBuffer *buffer
universe@483 135 ) {
universe@483 136 size_t len;
universe@483 137 if (cx_szmul(size, nitems, &len)) {
universe@483 138 return 0;
universe@483 139 }
universe@483 140 size_t required = buffer->pos + len;
universe@483 141 if (buffer->pos > required) {
universe@483 142 return 0;
universe@483 143 }
universe@483 144
universe@483 145 if (required > buffer->capacity) {
universe@483 146 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
universe@483 147 if (cxBufferMinimumCapacity(buffer, required)) {
universe@483 148 return 0;
universe@483 149 }
universe@483 150 } else {
universe@483 151 len = buffer->capacity - buffer->pos;
universe@483 152 if (size > 1) {
universe@483 153 len -= len % size;
universe@483 154 }
universe@483 155 }
universe@483 156 }
universe@483 157
universe@483 158 if (len == 0) {
universe@483 159 return len;
universe@483 160 }
universe@483 161
universe@483 162 memcpy(buffer->bytes + buffer->pos, ptr, len);
universe@483 163 buffer->pos += len;
universe@483 164 if (buffer->pos > buffer->size) {
universe@483 165 buffer->size = buffer->pos;
universe@483 166 }
universe@483 167
universe@483 168 return len / size;
universe@483 169 }
universe@483 170
universe@483 171 size_t cxBufferRead(
universe@483 172 void *ptr,
universe@483 173 size_t size,
universe@483 174 size_t nitems,
universe@500 175 CxBuffer *buffer
universe@483 176 ) {
universe@483 177 size_t len;
universe@483 178 if (cx_szmul(size, nitems, &len)) {
universe@483 179 return 0;
universe@483 180 }
universe@483 181 if (buffer->pos + len > buffer->size) {
universe@483 182 len = buffer->size - buffer->pos;
universe@483 183 if (size > 1) len -= len % size;
universe@483 184 }
universe@483 185
universe@483 186 if (len <= 0) {
universe@483 187 return len;
universe@483 188 }
universe@483 189
universe@483 190 memcpy(ptr, buffer->bytes + buffer->pos, len);
universe@483 191 buffer->pos += len;
universe@483 192
universe@483 193 return len / size;
universe@483 194 }
universe@483 195
universe@483 196 int cxBufferPut(
universe@500 197 CxBuffer *buffer,
universe@483 198 int c
universe@483 199 ) {
universe@483 200 if (buffer->pos >= buffer->capacity) {
universe@483 201 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
universe@483 202 if (cxBufferMinimumCapacity(buffer, buffer->capacity + 1)) {
universe@483 203 return EOF;
universe@483 204 }
universe@483 205 } else {
universe@483 206 return EOF;
universe@483 207 }
universe@483 208 }
universe@483 209
universe@483 210 c &= 0xFF;
universe@483 211 buffer->bytes[buffer->pos] = (unsigned char) c;
universe@483 212 buffer->pos++;
universe@483 213 if (buffer->pos > buffer->size) {
universe@483 214 buffer->size = buffer->pos;
universe@483 215 }
universe@483 216 return c;
universe@483 217 }
universe@483 218
universe@500 219 int cxBufferGet(CxBuffer *buffer) {
universe@483 220 if (cxBufferEof(buffer)) {
universe@483 221 return EOF;
universe@483 222 } else {
universe@483 223 int c = buffer->bytes[buffer->pos];
universe@483 224 buffer->pos++;
universe@483 225 return c;
universe@483 226 }
universe@483 227 }
universe@483 228
universe@483 229 size_t cxBufferPutString(
universe@500 230 CxBuffer *buffer,
universe@483 231 const char *str
universe@483 232 ) {
universe@483 233 return cxBufferWrite(str, 1, strlen(str), buffer);
universe@483 234 }
universe@483 235
universe@483 236 int cxBufferShiftLeft(
universe@500 237 CxBuffer *buffer,
universe@483 238 size_t shift
universe@483 239 ) {
universe@483 240 if (shift >= buffer->size) {
universe@483 241 buffer->pos = buffer->size = 0;
universe@483 242 } else {
universe@483 243 memmove(buffer->bytes, buffer->bytes + shift, buffer->size - shift);
universe@483 244 buffer->size -= shift;
universe@483 245
universe@483 246 if (buffer->pos >= shift) {
universe@483 247 buffer->pos -= shift;
universe@483 248 } else {
universe@483 249 buffer->pos = 0;
universe@483 250 }
universe@483 251 }
universe@483 252 return 0;
universe@483 253 }
universe@483 254
universe@483 255 int cxBufferShiftRight(
universe@500 256 CxBuffer *buffer,
universe@483 257 size_t shift
universe@483 258 ) {
universe@483 259 size_t req_capacity = buffer->size + shift;
universe@483 260 size_t movebytes;
universe@483 261
universe@483 262 // auto extend buffer, if required and enabled
universe@483 263 if (buffer->capacity < req_capacity) {
universe@483 264 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
universe@483 265 if (cxBufferMinimumCapacity(buffer, req_capacity)) {
universe@483 266 return 1;
universe@483 267 }
universe@483 268 movebytes = buffer->size;
universe@483 269 } else {
universe@483 270 movebytes = buffer->capacity - shift;
universe@483 271 }
universe@483 272 } else {
universe@483 273 movebytes = buffer->size;
universe@483 274 }
universe@483 275
universe@483 276 memmove(buffer->bytes + shift, buffer->bytes, movebytes);
universe@483 277 buffer->size = shift + movebytes;
universe@483 278
universe@483 279 buffer->pos += shift;
universe@483 280 if (buffer->pos > buffer->size) {
universe@483 281 buffer->pos = buffer->size;
universe@483 282 }
universe@483 283
universe@483 284 return 0;
universe@483 285 }
universe@483 286
universe@483 287 int cxBufferShift(
universe@500 288 CxBuffer *buffer,
universe@483 289 off_t shift
universe@483 290 ) {
universe@483 291 if (shift < 0) {
universe@483 292 return cxBufferShiftLeft(buffer, (size_t) (-shift));
universe@483 293 } else if (shift > 0) {
universe@483 294 return cxBufferShiftRight(buffer, (size_t) shift);
universe@483 295 } else {
universe@483 296 return 0;
universe@483 297 }
universe@483 298 }

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