1 /* $NetBSD: buf.c,v 1.25 2012/04/24 20:26:58 sjg Exp $ */
2
3 /*
4 * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Adam de Boor.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * Copyright (c) 1988, 1989 by Adam de Boor
37 * Copyright (c) 1989 by Berkeley Softworks
38 * All rights reserved.
39 *
40 * This code is derived from software contributed to Berkeley by
41 * Adam de Boor.
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by the University of
54 * California, Berkeley and its contributors.
55 * 4. Neither the name of the University nor the names of its contributors
56 * may be used to endorse or promote products derived from this software
57 * without specific prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69 * SUCH DAMAGE.
70 */
71
72 #ifndef MAKE_NATIVE
73 static char rcsid[] = "$NetBSD: buf.c,v 1.25 2012/04/24 20:26:58 sjg Exp $";
74 #else
75 #include <sys/cdefs.h>
76 #ifndef lint
77 #if 0
78 static char sccsid[] = "@(#)buf.c 8.1 (Berkeley) 6/6/93";
79 #else
80 __RCSID("$NetBSD: buf.c,v 1.25 2012/04/24 20:26:58 sjg Exp $");
81 #endif
82 #endif /* not lint */
83 #endif
84
85 /*-
86 * buf.c --
87 * Functions for automatically-expanded buffers.
88 */
89
90 #include "make.h"
91 #include "buf.h"
92
93 #ifndef max
94 #define max(a,b) ((a) > (b) ? (a) : (b))
95 #endif
96
97 #define BUF_DEF_SIZE 256 /* Default buffer size */
98
99 /*-
100 *-----------------------------------------------------------------------
101 * Buf_Expand_1 --
102 * Extend buffer for single byte add.
103 *
104 *-----------------------------------------------------------------------
105 */
106 void
Buf_Expand_1(Buffer * bp)107 Buf_Expand_1(Buffer *bp)
108 {
109 bp->size += max(bp->size, 16);
110 bp->buffer = bmake_realloc(bp->buffer, bp->size);
111 }
112
113 /*-
114 *-----------------------------------------------------------------------
115 * Buf_AddBytes --
116 * Add a number of bytes to the buffer.
117 *
118 * Results:
119 * None.
120 *
121 * Side Effects:
122 * Guess what?
123 *
124 *-----------------------------------------------------------------------
125 */
126 void
Buf_AddBytes(Buffer * bp,int numBytes,const Byte * bytesPtr)127 Buf_AddBytes(Buffer *bp, int numBytes, const Byte *bytesPtr)
128 {
129 int count = bp->count;
130 Byte *ptr;
131
132 if (__predict_false(count + numBytes >= bp->size)) {
133 bp->size += max(bp->size, numBytes + 16);
134 bp->buffer = bmake_realloc(bp->buffer, bp->size);
135 }
136
137 ptr = bp->buffer + count;
138 bp->count = count + numBytes;
139 ptr[numBytes] = 0;
140 memcpy(ptr, bytesPtr, numBytes);
141 }
142
143 /*-
144 *-----------------------------------------------------------------------
145 * Buf_GetAll --
146 * Get all the available data at once.
147 *
148 * Results:
149 * A pointer to the data and the number of bytes available.
150 *
151 * Side Effects:
152 * None.
153 *
154 *-----------------------------------------------------------------------
155 */
156 Byte *
Buf_GetAll(Buffer * bp,int * numBytesPtr)157 Buf_GetAll(Buffer *bp, int *numBytesPtr)
158 {
159
160 if (numBytesPtr != NULL)
161 *numBytesPtr = bp->count;
162
163 return (bp->buffer);
164 }
165
166 /*-
167 *-----------------------------------------------------------------------
168 * Buf_Empty --
169 * Throw away bytes in a buffer.
170 *
171 * Results:
172 * None.
173 *
174 * Side Effects:
175 * The bytes are discarded.
176 *
177 *-----------------------------------------------------------------------
178 */
179 void
Buf_Empty(Buffer * bp)180 Buf_Empty(Buffer *bp)
181 {
182
183 bp->count = 0;
184 *bp->buffer = 0;
185 }
186
187 /*-
188 *-----------------------------------------------------------------------
189 * Buf_Init --
190 * Initialize a buffer. If no initial size is given, a reasonable
191 * default is used.
192 *
193 * Input:
194 * size Initial size for the buffer
195 *
196 * Results:
197 * A buffer to be given to other functions in this library.
198 *
199 * Side Effects:
200 * The buffer is created, the space allocated and pointers
201 * initialized.
202 *
203 *-----------------------------------------------------------------------
204 */
205 void
Buf_Init(Buffer * bp,int size)206 Buf_Init(Buffer *bp, int size)
207 {
208 if (size <= 0) {
209 size = BUF_DEF_SIZE;
210 }
211 bp->size = size;
212 bp->count = 0;
213 bp->buffer = bmake_malloc(size);
214 *bp->buffer = 0;
215 }
216
217 /*-
218 *-----------------------------------------------------------------------
219 * Buf_Destroy --
220 * Nuke a buffer and all its resources.
221 *
222 * Input:
223 * buf Buffer to destroy
224 * freeData TRUE if the data should be destroyed
225 *
226 * Results:
227 * Data buffer, NULL if freed
228 *
229 * Side Effects:
230 * The buffer is freed.
231 *
232 *-----------------------------------------------------------------------
233 */
234 Byte *
Buf_Destroy(Buffer * buf,Boolean freeData)235 Buf_Destroy(Buffer *buf, Boolean freeData)
236 {
237 Byte *data;
238
239 data = buf->buffer;
240 if (freeData) {
241 free(data);
242 data = NULL;
243 }
244
245 buf->size = 0;
246 buf->count = 0;
247 buf->buffer = NULL;
248
249 return data;
250 }
251
252
253 /*-
254 *-----------------------------------------------------------------------
255 * Buf_DestroyCompact --
256 * Nuke a buffer and return its data.
257 *
258 * Input:
259 * buf Buffer to destroy
260 *
261 * Results:
262 * Data buffer
263 *
264 * Side Effects:
265 * If the buffer size is much greater than its content,
266 * a new buffer will be allocated and the old one freed.
267 *
268 *-----------------------------------------------------------------------
269 */
270 #ifndef BUF_COMPACT_LIMIT
271 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */
272 #endif
273
274 Byte *
Buf_DestroyCompact(Buffer * buf)275 Buf_DestroyCompact(Buffer *buf)
276 {
277 #if BUF_COMPACT_LIMIT > 0
278 Byte *data;
279
280 if (buf->size - buf->count >= BUF_COMPACT_LIMIT) {
281 /* We trust realloc to be smart */
282 data = bmake_realloc(buf->buffer, buf->count + 1);
283 if (data) {
284 data[buf->count] = 0;
285 Buf_Destroy(buf, FALSE);
286 return data;
287 }
288 }
289 #endif
290 return Buf_Destroy(buf, FALSE);
291 }
292