Sun, 24 Apr 2022 17:44:52 +0200
fix cxBufferMinimumCapacity not using the allocator
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 <stdio.h>
34 #include <string.h>
36 int cxBufferInit(
37 CxBuffer *buffer,
38 void *space,
39 size_t capacity,
40 CxAllocator const *allocator,
41 int flags
42 ) {
43 buffer->allocator = allocator;
44 buffer->flags = flags;
45 if (!space) {
46 buffer->bytes = cxMalloc(allocator, capacity);
47 if (buffer->bytes == NULL) {
48 return 1;
49 }
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 int cxBufferSeek(
69 CxBuffer *buffer,
70 off_t offset,
71 int whence
72 ) {
73 size_t npos;
74 switch (whence) {
75 case SEEK_CUR:
76 npos = buffer->pos;
77 break;
78 case SEEK_END:
79 npos = buffer->size;
80 break;
81 case SEEK_SET:
82 npos = 0;
83 break;
84 default:
85 return -1;
86 }
88 size_t opos = npos;
89 npos += offset;
91 if ((offset > 0 && npos < opos) || (offset < 0 && npos > opos)) {
92 return -1;
93 }
95 if (npos >= buffer->size) {
96 return -1;
97 } else {
98 buffer->pos = npos;
99 return 0;
100 }
102 }
104 void cxBufferClear(CxBuffer *buffer) {
105 memset(buffer->bytes, 0, buffer->size);
106 buffer->size = 0;
107 buffer->pos = 0;
108 }
110 int cxBufferEof(CxBuffer const *buffer) {
111 return buffer->pos >= buffer->size;
112 }
114 int cxBufferMinimumCapacity(
115 CxBuffer *buffer,
116 size_t newcap
117 ) {
118 if (newcap <= buffer->capacity) {
119 return 0;
120 }
122 if (cxReallocate(buffer->allocator, &buffer->bytes, newcap) == 0) {
123 buffer->capacity = newcap;
124 return 0;
125 } else {
126 return -1;
127 }
128 }
130 size_t cxBufferWrite(
131 void const *ptr,
132 size_t size,
133 size_t nitems,
134 CxBuffer *buffer
135 ) {
136 size_t len;
137 if (cx_szmul(size, nitems, &len)) {
138 return 0;
139 }
140 size_t required = buffer->pos + len;
141 if (buffer->pos > required) {
142 return 0;
143 }
145 if (required > buffer->capacity) {
146 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
147 if (cxBufferMinimumCapacity(buffer, required)) {
148 return 0;
149 }
150 } else {
151 len = buffer->capacity - buffer->pos;
152 if (size > 1) {
153 len -= len % size;
154 }
155 }
156 }
158 if (len == 0) {
159 return len;
160 }
162 memcpy(buffer->bytes + buffer->pos, ptr, len);
163 buffer->pos += len;
164 if (buffer->pos > buffer->size) {
165 buffer->size = buffer->pos;
166 }
168 return len / size;
169 }
171 size_t cxBufferRead(
172 void *ptr,
173 size_t size,
174 size_t nitems,
175 CxBuffer *buffer
176 ) {
177 size_t len;
178 if (cx_szmul(size, nitems, &len)) {
179 return 0;
180 }
181 if (buffer->pos + len > buffer->size) {
182 len = buffer->size - buffer->pos;
183 if (size > 1) len -= len % size;
184 }
186 if (len <= 0) {
187 return len;
188 }
190 memcpy(ptr, buffer->bytes + buffer->pos, len);
191 buffer->pos += len;
193 return len / size;
194 }
196 int cxBufferPut(
197 CxBuffer *buffer,
198 int c
199 ) {
200 if (buffer->pos >= buffer->capacity) {
201 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
202 if (cxBufferMinimumCapacity(buffer, buffer->capacity + 1)) {
203 return EOF;
204 }
205 } else {
206 return EOF;
207 }
208 }
210 c &= 0xFF;
211 buffer->bytes[buffer->pos] = (unsigned char) c;
212 buffer->pos++;
213 if (buffer->pos > buffer->size) {
214 buffer->size = buffer->pos;
215 }
216 return c;
217 }
219 int cxBufferGet(CxBuffer *buffer) {
220 if (cxBufferEof(buffer)) {
221 return EOF;
222 } else {
223 int c = buffer->bytes[buffer->pos];
224 buffer->pos++;
225 return c;
226 }
227 }
229 size_t cxBufferPutString(
230 CxBuffer *buffer,
231 const char *str
232 ) {
233 return cxBufferWrite(str, 1, strlen(str), buffer);
234 }
236 int cxBufferShiftLeft(
237 CxBuffer *buffer,
238 size_t shift
239 ) {
240 if (shift >= buffer->size) {
241 buffer->pos = buffer->size = 0;
242 } else {
243 memmove(buffer->bytes, buffer->bytes + shift, buffer->size - shift);
244 buffer->size -= shift;
246 if (buffer->pos >= shift) {
247 buffer->pos -= shift;
248 } else {
249 buffer->pos = 0;
250 }
251 }
252 return 0;
253 }
255 int cxBufferShiftRight(
256 CxBuffer *buffer,
257 size_t shift
258 ) {
259 size_t req_capacity = buffer->size + shift;
260 size_t movebytes;
262 // auto extend buffer, if required and enabled
263 if (buffer->capacity < req_capacity) {
264 if ((buffer->flags & CX_BUFFER_AUTO_EXTEND) == CX_BUFFER_AUTO_EXTEND) {
265 if (cxBufferMinimumCapacity(buffer, req_capacity)) {
266 return 1;
267 }
268 movebytes = buffer->size;
269 } else {
270 movebytes = buffer->capacity - shift;
271 }
272 } else {
273 movebytes = buffer->size;
274 }
276 memmove(buffer->bytes + shift, buffer->bytes, movebytes);
277 buffer->size = shift + movebytes;
279 buffer->pos += shift;
280 if (buffer->pos > buffer->size) {
281 buffer->pos = buffer->size;
282 }
284 return 0;
285 }
287 int cxBufferShift(
288 CxBuffer *buffer,
289 off_t shift
290 ) {
291 if (shift < 0) {
292 return cxBufferShiftLeft(buffer, (size_t) (-shift));
293 } else if (shift > 0) {
294 return cxBufferShiftRight(buffer, (size_t) shift);
295 } else {
296 return 0;
297 }
298 }