1 /* $NetBSD: buf.c,v 1.51 2021/01/30 21:18:14 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 /* Automatically-expanding null-terminated character buffers. */
73
74 #include <limits.h>
75 #include "make.h"
76
77 /* "@(#)buf.c 8.1 (Berkeley) 6/6/93" */
78 MAKE_RCSID("$NetBSD: buf.c,v 1.51 2021/01/30 21:18:14 rillig Exp $");
79
80 /* Make space in the buffer for adding at least 16 more bytes. */
81 void
Buf_Expand(Buffer * buf)82 Buf_Expand(Buffer *buf)
83 {
84 buf->cap += buf->cap > 16 ? buf->cap : 16;
85 buf->data = bmake_realloc(buf->data, buf->cap);
86 }
87
88 /* Add the bytes to the buffer. */
89 void
Buf_AddBytes(Buffer * buf,const char * bytes,size_t bytes_len)90 Buf_AddBytes(Buffer *buf, const char *bytes, size_t bytes_len)
91 {
92 size_t old_len = buf->len;
93 char *end;
94
95 if (old_len + bytes_len >= buf->cap) {
96 size_t minIncr = bytes_len + 16;
97 buf->cap += buf->cap > minIncr ? buf->cap : minIncr;
98 buf->data = bmake_realloc(buf->data, buf->cap);
99 }
100
101 end = buf->data + old_len;
102 buf->len = old_len + bytes_len;
103 memcpy(end, bytes, bytes_len);
104 end[bytes_len] = '\0';
105 }
106
107 /* Add the bytes between start and end to the buffer. */
108 void
Buf_AddBytesBetween(Buffer * buf,const char * start,const char * end)109 Buf_AddBytesBetween(Buffer *buf, const char *start, const char *end)
110 {
111 Buf_AddBytes(buf, start, (size_t)(end - start));
112 }
113
114 /* Add the string to the buffer. */
115 void
Buf_AddStr(Buffer * buf,const char * str)116 Buf_AddStr(Buffer *buf, const char *str)
117 {
118 Buf_AddBytes(buf, str, strlen(str));
119 }
120
121 /* Add the number to the buffer. */
122 void
Buf_AddInt(Buffer * buf,int n)123 Buf_AddInt(Buffer *buf, int n)
124 {
125 enum {
126 bits = sizeof(int) * CHAR_BIT,
127 max_octal_digits = (bits + 2) / 3,
128 max_decimal_digits = /* at most */ max_octal_digits,
129 max_sign_chars = 1,
130 str_size = max_sign_chars + max_decimal_digits + 1
131 };
132 char str[str_size];
133
134 size_t len = (size_t)snprintf(str, sizeof str, "%d", n);
135 Buf_AddBytes(buf, str, len);
136 }
137
138 /* Mark the buffer as empty, so it can be filled with data again. */
139 void
Buf_Empty(Buffer * buf)140 Buf_Empty(Buffer *buf)
141 {
142 buf->len = 0;
143 buf->data[0] = '\0';
144 }
145
146 /* Initialize a buffer. */
147 void
Buf_InitSize(Buffer * buf,size_t cap)148 Buf_InitSize(Buffer *buf, size_t cap)
149 {
150 buf->cap = cap;
151 buf->len = 0;
152 buf->data = bmake_malloc(cap);
153 buf->data[0] = '\0';
154 }
155
156 void
Buf_Init(Buffer * buf)157 Buf_Init(Buffer *buf)
158 {
159 Buf_InitSize(buf, 256);
160 }
161
162 /*
163 * Free the data from the buffer.
164 * Leave the buffer itself in an indeterminate state.
165 */
166 void
Buf_Done(Buffer * buf)167 Buf_Done(Buffer *buf)
168 {
169 free(buf->data);
170
171 #ifdef CLEANUP
172 buf->cap = 0;
173 buf->len = 0;
174 buf->data = NULL;
175 #endif
176 }
177
178 /*
179 * Return the data from the buffer.
180 * Leave the buffer itself in an indeterminate state.
181 */
182 char *
Buf_DoneData(Buffer * buf)183 Buf_DoneData(Buffer *buf)
184 {
185 char *data = buf->data;
186
187 #ifdef CLEANUP
188 buf->cap = 0;
189 buf->len = 0;
190 buf->data = NULL;
191 #endif
192
193 return data;
194 }
195
196 #ifndef BUF_COMPACT_LIMIT
197 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */
198 #endif
199
200 /*
201 * Return the data from the buffer.
202 * Leave the buffer itself in an indeterminate state.
203 *
204 * If the buffer size is much greater than its content,
205 * a new buffer will be allocated and the old one freed.
206 */
207 char *
Buf_DoneDataCompact(Buffer * buf)208 Buf_DoneDataCompact(Buffer *buf)
209 {
210 #if BUF_COMPACT_LIMIT > 0
211 if (buf->cap - buf->len >= BUF_COMPACT_LIMIT) {
212 /* We trust realloc to be smart */
213 char *data = bmake_realloc(buf->data, buf->len + 1);
214 data[buf->len] = '\0'; /* XXX: unnecessary */
215 Buf_DoneData(buf);
216 return data;
217 }
218 #endif
219 return Buf_DoneData(buf);
220 }
221