Sat, 16 Apr 2022 20:17:01 +0200
improve testing allocator + add tests for it
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
29 #include "cx/buffer.h"
30 #include "cx/utils.h"
32 #include <stdlib.h>
33 #include <string.h>
35 int cxBufferInit(
36 CxBuffer *buffer,
37 void *space,
38 size_t capacity,
39 CxAllocator *allocator,
40 int flags
41 ) {
42 buffer->allocator = allocator;
43 buffer->flags = flags;
44 if (!space) {
45 buffer->bytes = cxMalloc(allocator, capacity);
46 if (buffer->bytes == NULL) {
47 return 1;
48 }
49 memset(buffer->bytes, 0, capacity);
50 buffer->flags |= CX_BUFFER_FREE_CONTENTS;
51 } else {
52 buffer->bytes = space;
53 }
54 buffer->capacity = capacity;
55 buffer->size = 0;
57 buffer->pos = 0;
59 return 0;
60 }
62 void cxBufferDestroy(CxBuffer *buffer) {
63 if ((buffer->flags & CX_BUFFER_FREE_CONTENTS) == CX_BUFFER_FREE_CONTENTS) {
64 cxFree(buffer->allocator, buffer->bytes);
65 }
66 }
68 CxBuffer *cxBufferExtract(
69 CxBuffer *src,
70 size_t start,
71 size_t length,
72 int flags
73 ) {
74 if (src->size == 0 || length == 0 ||
75 ((size_t) -1) - start < length || start + length > src->capacity) {
76 return NULL;
77 }
79 CxBuffer *dst = (CxBuffer *) malloc(sizeof(cx_buffer_s));
80 if (dst) {
81 dst->bytes = malloc(length);
82 if (!dst->bytes) {
83 free(dst);
84 return NULL;
85 }
86 dst->capacity = length;
87 dst->size = length;
88 dst->flags = flags | CX_BUFFER_FREE_CONTENTS;
89 dst->pos = 0;
90 memcpy(dst->bytes, src->bytes + start, length);
91 }
92 return dst;
93 }
95 int cxBufferSeek(
96 CxBuffer *buffer,
97 off_t offset,
98 int whence
99 ) {
100 size_t npos;
101 switch (whence) {
102 case SEEK_CUR:
103 npos = buffer->pos;
104 break;
105 case SEEK_END:
106 npos = buffer->size;
107 break;
108 case SEEK_SET:
109 npos = 0;
110 break;
111 default:
112 return -1;
113 }
115 size_t opos = npos;
116 npos += offset;
118 if ((offset > 0 && npos < opos) || (offset < 0 && npos > opos)) {
119 return -1;
120 }
122 if (npos >= buffer->size) {
123 return -1;
124 } else {
125 buffer->pos = npos;
126 return 0;
127 }
129 }
131 int cxBufferEof(CxBuffer *buffer) {
132 return buffer->pos >= buffer->size;
133 }
135 int cxBufferMinimumCapacity(
136 CxBuffer *buffer,
137 size_t additional_bytes
138 ) {
139 size_t newcap = buffer->capacity + additional_bytes;
141 // overflow protection
142 if (newcap < buffer->capacity) {
143 return -1;
144 }
146 unsigned char *newspace = realloc(buffer->bytes, newcap);
147 if (newspace) {
148 memset(newspace + buffer->size, 0, newcap - buffer->size);
149 buffer->bytes = newspace;
150 buffer->capacity = newcap;
151 } else {
152 return -1;
153 }
155 return 0;
156 }
158 size_t cxBufferWrite(
159 void const *ptr,
160 size_t size,
161 size_t nitems,
162 CxBuffer *buffer
163 ) {
164 size_t len;
165 if (cx_szmul(size, nitems, &len)) {
166 return 0;
167 }
168 size_t required = buffer->pos + len;
169 if (buffer->pos > required) {
170 return 0;
171 }
173 if (required > buffer->capacity) {
174 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
175 if (cxBufferMinimumCapacity(buffer, required)) {
176 return 0;
177 }
178 } else {
179 len = buffer->capacity - buffer->pos;
180 if (size > 1) {
181 len -= len % size;
182 }
183 }
184 }
186 if (len == 0) {
187 return len;
188 }
190 memcpy(buffer->bytes + buffer->pos, ptr, len);
191 buffer->pos += len;
192 if (buffer->pos > buffer->size) {
193 buffer->size = buffer->pos;
194 }
196 return len / size;
197 }
199 size_t cxBufferRead(
200 void *ptr,
201 size_t size,
202 size_t nitems,
203 CxBuffer *buffer
204 ) {
205 size_t len;
206 if (cx_szmul(size, nitems, &len)) {
207 return 0;
208 }
209 if (buffer->pos + len > buffer->size) {
210 len = buffer->size - buffer->pos;
211 if (size > 1) len -= len % size;
212 }
214 if (len <= 0) {
215 return len;
216 }
218 memcpy(ptr, buffer->bytes + buffer->pos, len);
219 buffer->pos += len;
221 return len / size;
222 }
224 int cxBufferPut(
225 CxBuffer *buffer,
226 int c
227 ) {
228 if (buffer->pos >= buffer->capacity) {
229 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
230 if (cxBufferMinimumCapacity(buffer, buffer->capacity + 1)) {
231 return EOF;
232 }
233 } else {
234 return EOF;
235 }
236 }
238 c &= 0xFF;
239 buffer->bytes[buffer->pos] = (unsigned char) c;
240 buffer->pos++;
241 if (buffer->pos > buffer->size) {
242 buffer->size = buffer->pos;
243 }
244 return c;
245 }
247 int cxBufferGet(CxBuffer *buffer) {
248 if (cxBufferEof(buffer)) {
249 return EOF;
250 } else {
251 int c = buffer->bytes[buffer->pos];
252 buffer->pos++;
253 return c;
254 }
255 }
257 size_t cxBufferPutString(
258 CxBuffer *buffer,
259 const char *str
260 ) {
261 return cxBufferWrite(str, 1, strlen(str), buffer);
262 }
264 int cxBufferShiftLeft(
265 CxBuffer *buffer,
266 size_t shift
267 ) {
268 if (shift >= buffer->size) {
269 buffer->pos = buffer->size = 0;
270 } else {
271 memmove(buffer->bytes, buffer->bytes + shift, buffer->size - shift);
272 buffer->size -= shift;
274 if (buffer->pos >= shift) {
275 buffer->pos -= shift;
276 } else {
277 buffer->pos = 0;
278 }
279 }
280 return 0;
281 }
283 int cxBufferShiftRight(
284 CxBuffer *buffer,
285 size_t shift
286 ) {
287 size_t req_capacity = buffer->size + shift;
288 size_t movebytes;
290 // auto extend buffer, if required and enabled
291 if (buffer->capacity < req_capacity) {
292 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
293 if (cxBufferMinimumCapacity(buffer, req_capacity)) {
294 return 1;
295 }
296 movebytes = buffer->size;
297 } else {
298 movebytes = buffer->capacity - shift;
299 }
300 } else {
301 movebytes = buffer->size;
302 }
304 memmove(buffer->bytes + shift, buffer->bytes, movebytes);
305 buffer->size = shift + movebytes;
307 buffer->pos += shift;
308 if (buffer->pos > buffer->size) {
309 buffer->pos = buffer->size;
310 }
312 return 0;
313 }
315 int cxBufferShift(
316 CxBuffer *buffer,
317 off_t shift
318 ) {
319 if (shift < 0) {
320 return cxBufferShiftLeft(buffer, (size_t) (-shift));
321 } else if (shift > 0) {
322 return cxBufferShiftRight(buffer, (size_t) shift);
323 } else {
324 return 0;
325 }
326 }