buf.c revision 1.37 1 /* $NetBSD: buf.c,v 1.37 2020/08/23 08:21:50 rillig 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 1.37 2020/08/23 08:21:50 rillig 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 1.37 2020/08/23 08:21:50 rillig Exp $");
81 #endif
82 #endif /* not lint */
83 #endif
84
85 /* Functions for automatically-expanded null-terminated buffers. */
86
87 #include <limits.h>
88 #include "make.h"
89
90 /* Extend the buffer for adding a single byte. */
91 void
92 Buf_Expand_1(Buffer *bp)
93 {
94 bp->size += MAX(bp->size, 16);
95 bp->buffer = bmake_realloc(bp->buffer, bp->size);
96 }
97
98 /* Add the given bytes to the buffer. */
99 void
100 Buf_AddBytes(Buffer *bp, const char *bytesPtr, size_t numBytes)
101 {
102 size_t count = bp->count;
103 char *ptr;
104
105 if (__predict_false(count + numBytes >= bp->size)) {
106 bp->size += MAX(bp->size, numBytes + 16);
107 bp->buffer = bmake_realloc(bp->buffer, bp->size);
108 }
109
110 ptr = bp->buffer + count;
111 bp->count = count + numBytes;
112 memcpy(ptr, bytesPtr, numBytes);
113 ptr[numBytes] = '\0';
114 }
115
116 /* Add the bytes between start and end to the buffer. */
117 void
118 Buf_AddBytesBetween(Buffer *bp, const char *start, const char *end)
119 {
120 Buf_AddBytes(bp, start, (size_t)(end - start));
121 }
122
123 /* Add the given string to the buffer. */
124 void
125 Buf_AddStr(Buffer *bp, const char *str)
126 {
127 Buf_AddBytes(bp, str, strlen(str));
128 }
129
130 /* Add the given number to the buffer. */
131 void
132 Buf_AddInt(Buffer *bp, int n)
133 {
134 enum {
135 bits = sizeof(int) * CHAR_BIT,
136 max_octal_digits = (bits + 2) / 3,
137 max_decimal_digits = /* at most */ max_octal_digits,
138 max_sign_chars = 1,
139 buf_size = max_sign_chars + max_decimal_digits + 1
140 };
141 char buf[buf_size];
142
143 size_t len = (size_t)snprintf(buf, sizeof buf, "%d", n);
144 Buf_AddBytes(bp, buf, len);
145 }
146
147 /* Get the data (usually a string) from the buffer.
148 * The returned data is valid until the next modifying operation
149 * on the buffer.
150 *
151 * Returns the pointer to the data and optionally the length of the
152 * data in the buffer. */
153 char *
154 Buf_GetAll(Buffer *bp, size_t *numBytesPtr)
155 {
156 if (numBytesPtr != NULL)
157 *numBytesPtr = bp->count;
158 return bp->buffer;
159 }
160
161 /* Mark the buffer as empty, so it can be filled with data again. */
162 void
163 Buf_Empty(Buffer *bp)
164 {
165 bp->count = 0;
166 bp->buffer[0] = '\0';
167 }
168
169 /* Initialize a buffer.
170 * If the given initial size is 0, a reasonable default is used. */
171 void
172 Buf_Init(Buffer *bp, size_t size)
173 {
174 if (size <= 0) {
175 size = 256;
176 }
177 bp->size = size;
178 bp->count = 0;
179 bp->buffer = bmake_malloc(size);
180 bp->buffer[0] = '\0';
181 }
182
183 /* Reset the buffer.
184 * If freeData is TRUE, the data from the buffer is freed as well.
185 * Otherwise it is kept and returned. */
186 char *
187 Buf_Destroy(Buffer *buf, Boolean freeData)
188 {
189 char *data = buf->buffer;
190 if (freeData) {
191 free(data);
192 data = NULL;
193 }
194
195 buf->size = 0;
196 buf->count = 0;
197 buf->buffer = NULL;
198
199 return data;
200 }
201
202 #ifndef BUF_COMPACT_LIMIT
203 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */
204 #endif
205
206 /* Reset the buffer and return its data.
207 *
208 * If the buffer size is much greater than its content,
209 * a new buffer will be allocated and the old one freed. */
210 char *
211 Buf_DestroyCompact(Buffer *buf)
212 {
213 #if BUF_COMPACT_LIMIT > 0
214 if (buf->size - buf->count >= BUF_COMPACT_LIMIT) {
215 /* We trust realloc to be smart */
216 char *data = bmake_realloc(buf->buffer, buf->count + 1);
217 data[buf->count] = '\0';
218 Buf_Destroy(buf, FALSE);
219 return data;
220 }
221 #endif
222 return Buf_Destroy(buf, FALSE);
223 }
224