buf.c revision 1.40
1 /* $NetBSD: buf.c,v 1.40 2020/09/27 16:59:02 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 /* Functions for automatically-expanded 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 1.40 2020/09/27 16:59:02 rillig Exp $"); 79 80 /* Extend the buffer for adding a single byte. */ 81 void 82 Buf_Expand_1(Buffer *buf) 83 { 84 buf->cap += MAX(buf->cap, 16); 85 buf->data = bmake_realloc(buf->data, buf->cap); 86 } 87 88 /* Add the given 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 += MAX(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 given 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 given 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 pointer to the data and optionally the length of the 142 * data in the buffer. */ 143 char * 144 Buf_GetAll(Buffer *buf, size_t *out_len) 145 { 146 if (out_len != NULL) 147 *out_len = buf->len; 148 return buf->data; 149 } 150 151 /* Mark the buffer as empty, so it can be filled with data again. */ 152 void 153 Buf_Empty(Buffer *buf) 154 { 155 buf->len = 0; 156 buf->data[0] = '\0'; 157 } 158 159 /* Initialize a buffer. 160 * If the given initial capacity is 0, a reasonable default is used. */ 161 void 162 Buf_Init(Buffer *buf, size_t cap) 163 { 164 if (cap <= 0) 165 cap = 256; 166 buf->cap = cap; 167 buf->len = 0; 168 buf->data = bmake_malloc(cap); 169 buf->data[0] = '\0'; 170 } 171 172 /* Reset the buffer. 173 * If freeData is TRUE, the data from the buffer is freed as well. 174 * Otherwise it is kept and returned. */ 175 char * 176 Buf_Destroy(Buffer *buf, Boolean freeData) 177 { 178 char *data = buf->data; 179 if (freeData) { 180 free(data); 181 data = NULL; 182 } 183 184 buf->cap = 0; 185 buf->len = 0; 186 buf->data = NULL; 187 188 return data; 189 } 190 191 #ifndef BUF_COMPACT_LIMIT 192 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */ 193 #endif 194 195 /* Reset the buffer and return its data. 196 * 197 * If the buffer size is much greater than its content, 198 * a new buffer will be allocated and the old one freed. */ 199 char * 200 Buf_DestroyCompact(Buffer *buf) 201 { 202 #if BUF_COMPACT_LIMIT > 0 203 if (buf->cap - buf->len >= BUF_COMPACT_LIMIT) { 204 /* We trust realloc to be smart */ 205 char *data = bmake_realloc(buf->data, buf->len + 1); 206 data[buf->len] = '\0'; /* XXX: unnecessary */ 207 Buf_Destroy(buf, FALSE); 208 return data; 209 } 210 #endif 211 return Buf_Destroy(buf, FALSE); 212 } 213
Indexes created Mon Sep 22 10:09:38 GMT 2025