buf.c revision 1.42
1 /* $NetBSD: buf.c,v 1.42 2020/10/24 20:51:49 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 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 1.42 2020/10/24 20:51:49 rillig Exp $"); 79 80 /* Make space in the buffer for adding a single byte. */ 81 void 82 Buf_Expand_1(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 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 (__predict_false(old_len + bytes_len >= buf->cap)) { 96 buf->cap += buf->cap > bytes_len + 16 ? buf->cap : bytes_len + 16; 97 buf->data = bmake_realloc(buf->data, buf->cap); 98 } 99 100 end = buf->data + old_len; 101 buf->len = old_len + bytes_len; 102 memcpy(end, bytes, bytes_len); 103 end[bytes_len] = '\0'; 104 } 105 106 /* Add the bytes between start and end to the buffer. */ 107 void 108 Buf_AddBytesBetween(Buffer *buf, const char *start, const char *end) 109 { 110 Buf_AddBytes(buf, start, (size_t)(end - start)); 111 } 112 113 /* Add the string to the buffer. */ 114 void 115 Buf_AddStr(Buffer *buf, const char *str) 116 { 117 Buf_AddBytes(buf, str, strlen(str)); 118 } 119 120 /* Add the number to the buffer. */ 121 void 122 Buf_AddInt(Buffer *buf, int n) 123 { 124 enum { 125 bits = sizeof(int) * CHAR_BIT, 126 max_octal_digits = (bits + 2) / 3, 127 max_decimal_digits = /* at most */ max_octal_digits, 128 max_sign_chars = 1, 129 str_size = max_sign_chars + max_decimal_digits + 1 130 }; 131 char str[str_size]; 132 133 size_t len = (size_t)snprintf(str, sizeof str, "%d", n); 134 Buf_AddBytes(buf, str, len); 135 } 136 137 /* Get the data (usually a string) from the buffer. 138 * The returned data is valid until the next modifying operation 139 * on the buffer. 140 * 141 * Returns the data and optionally the length of the data. */ 142 char * 143 Buf_GetAll(Buffer *buf, size_t *out_len) 144 { 145 if (out_len != NULL) 146 *out_len = buf->len; 147 return buf->data; 148 } 149 150 /* Mark the buffer as empty, so it can be filled with data again. */ 151 void 152 Buf_Empty(Buffer *buf) 153 { 154 buf->len = 0; 155 buf->data[0] = '\0'; 156 } 157 158 /* Initialize a buffer. 159 * If the given initial capacity is 0, a reasonable default is used. */ 160 void 161 Buf_Init(Buffer *buf, size_t cap) 162 { 163 if (cap <= 0) 164 cap = 256; 165 buf->cap = cap; 166 buf->len = 0; 167 buf->data = bmake_malloc(cap); 168 buf->data[0] = '\0'; 169 } 170 171 /* Reset the buffer. 172 * If freeData is TRUE, the data from the buffer is freed as well. 173 * Otherwise it is kept and returned. */ 174 char * 175 Buf_Destroy(Buffer *buf, Boolean freeData) 176 { 177 char *data = buf->data; 178 if (freeData) { 179 free(data); 180 data = NULL; 181 } 182 183 buf->cap = 0; 184 buf->len = 0; 185 buf->data = NULL; 186 187 return data; 188 } 189 190 #ifndef BUF_COMPACT_LIMIT 191 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */ 192 #endif 193 194 /* Reset the buffer and return its data. 195 * 196 * If the buffer size is much greater than its content, 197 * a new buffer will be allocated and the old one freed. */ 198 char * 199 Buf_DestroyCompact(Buffer *buf) 200 { 201 #if BUF_COMPACT_LIMIT > 0 202 if (buf->cap - buf->len >= BUF_COMPACT_LIMIT) { 203 /* We trust realloc to be smart */ 204 char *data = bmake_realloc(buf->data, buf->len + 1); 205 data[buf->len] = '\0'; /* XXX: unnecessary */ 206 Buf_Destroy(buf, FALSE); 207 return data; 208 } 209 #endif 210 return Buf_Destroy(buf, FALSE); 211 } 212
Indexes created Wed Oct 15 16:09:53 GMT 2025