1 /* $NetBSD: buf.c,v 1.47 2020/12/30 10:03:16 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 1.47 2020/12/30 10:03:16 rillig Exp $"); 79 80 /* Make space in the buffer for adding at least 16 more bytes. */ 81 void 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 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 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 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 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 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 /* 139 * Get the data (usually a string) from the buffer. 140 * The returned data is valid until the next modifying operation 141 * on the buffer. 142 * 143 * Returns the data and optionally the length of the data. 144 */ 145 char * 146 Buf_GetAll(Buffer *buf, size_t *out_len) 147 { 148 if (out_len != NULL) 149 *out_len = buf->len; 150 return buf->data; 151 } 152 153 /* Mark the buffer as empty, so it can be filled with data again. */ 154 void 155 Buf_Empty(Buffer *buf) 156 { 157 buf->len = 0; 158 buf->data[0] = '\0'; 159 } 160 161 /* Initialize a buffer. */ 162 void 163 Buf_InitSize(Buffer *buf, size_t cap) 164 { 165 buf->cap = cap; 166 buf->len = 0; 167 buf->data = bmake_malloc(cap); 168 buf->data[0] = '\0'; 169 } 170 171 void 172 Buf_Init(Buffer *buf) 173 { 174 Buf_InitSize(buf, 256); 175 } 176 177 /* 178 * Reset the buffer. 179 * If freeData is TRUE, the data from the buffer is freed as well. 180 * Otherwise it is kept and returned. 181 */ 182 char * 183 Buf_Destroy(Buffer *buf, Boolean freeData) 184 { 185 char *data = buf->data; 186 if (freeData) { 187 free(data); 188 data = NULL; 189 } 190 191 buf->cap = 0; 192 buf->len = 0; 193 buf->data = NULL; 194 195 return data; 196 } 197 198 #ifndef BUF_COMPACT_LIMIT 199 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */ 200 #endif 201 202 /* 203 * Reset the buffer and return its data. 204 * 205 * If the buffer size is much greater than its content, 206 * a new buffer will be allocated and the old one freed. 207 */ 208 char * 209 Buf_DestroyCompact(Buffer *buf) 210 { 211 #if BUF_COMPACT_LIMIT > 0 212 if (buf->cap - buf->len >= BUF_COMPACT_LIMIT) { 213 /* We trust realloc to be smart */ 214 char *data = bmake_realloc(buf->data, buf->len + 1); 215 data[buf->len] = '\0'; /* XXX: unnecessary */ 216 Buf_Destroy(buf, FALSE); 217 return data; 218 } 219 #endif 220 return Buf_Destroy(buf, FALSE); 221 } 222