1 /* $NetBSD: buf.c,v 1.35 2020/08/13 04:12:13 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 1.35 2020/08/13 04:12:13 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 1.35 2020/08/13 04:12:13 rillig Exp $"); 81 #endif 82 #endif /* not lint */ 83 #endif 84 85 /* Functions for automatically-expanded NUL-terminated buffers. */ 86 87 #include <limits.h> 88 #include "make.h" 89 #include "buf.h" 90 91 #ifndef max 92 #define max(a, b) ((a) > (b) ? (a) : (b)) 93 #endif 94 95 #define BUF_DEF_SIZE 256 /* Default buffer size */ 96 97 /* Extend the buffer for adding a single byte. */ 98 void 99 Buf_Expand_1(Buffer *bp) 100 { 101 bp->size += max(bp->size, 16); 102 bp->buffer = bmake_realloc(bp->buffer, bp->size); 103 } 104 105 /* Add the given bytes to the buffer. */ 106 void 107 Buf_AddBytes(Buffer *bp, const char *bytesPtr, size_t numBytes) 108 { 109 size_t count = bp->count; 110 char *ptr; 111 112 if (__predict_false(count + numBytes >= bp->size)) { 113 bp->size += max(bp->size, numBytes + 16); 114 bp->buffer = bmake_realloc(bp->buffer, bp->size); 115 } 116 117 ptr = bp->buffer + count; 118 bp->count = count + numBytes; 119 memcpy(ptr, bytesPtr, numBytes); 120 ptr[numBytes] = '\0'; 121 } 122 123 /* Add the bytes between start and end to the buffer. */ 124 void 125 Buf_AddBytesBetween(Buffer *bp, const char *start, const char *end) 126 { 127 Buf_AddBytes(bp, start, (size_t)(end - start)); 128 } 129 130 /* Add the given string to the buffer. */ 131 void 132 Buf_AddStr(Buffer *bp, const char *str) 133 { 134 Buf_AddBytes(bp, str, strlen(str)); 135 } 136 137 /* Add the given number to the buffer. */ 138 void 139 Buf_AddInt(Buffer *bp, int n) 140 { 141 /* 142 * We need enough space for the decimal representation of an int. 143 * We calculate the space needed for the octal representation, and 144 * add enough slop to cope with a '-' sign and a trailing '\0'. 145 */ 146 enum { 147 bits = sizeof(int) * CHAR_BIT, 148 buf_size = 1 + (bits + 2) / 3 + 1 149 }; 150 char buf[buf_size]; 151 152 size_t len = (size_t)snprintf(buf, sizeof buf, "%d", n); 153 Buf_AddBytes(bp, buf, len); 154 } 155 156 /* Get the data (usually a string) from the buffer. 157 * The returned data is valid until the next modifying operation 158 * on the buffer. 159 * 160 * Returns the pointer to the data and optionally the length of the 161 * data in the buffer. */ 162 char * 163 Buf_GetAll(Buffer *bp, size_t *numBytesPtr) 164 { 165 if (numBytesPtr != NULL) 166 *numBytesPtr = bp->count; 167 return bp->buffer; 168 } 169 170 /* Mark the buffer as empty, so it can be filled with data again. */ 171 void 172 Buf_Empty(Buffer *bp) 173 { 174 bp->count = 0; 175 bp->buffer[0] = '\0'; 176 } 177 178 /* Initialize a buffer. 179 * If the given initial size is 0, a reasonable default is used. */ 180 void 181 Buf_Init(Buffer *bp, size_t size) 182 { 183 if (size <= 0) { 184 size = BUF_DEF_SIZE; 185 } 186 bp->size = size; 187 bp->count = 0; 188 bp->buffer = bmake_malloc(size); 189 *bp->buffer = 0; 190 } 191 192 /* Reset the buffer. 193 * If freeData is TRUE, the data from the buffer is freed as well. 194 * Otherwise it is kept and returned. */ 195 char * 196 Buf_Destroy(Buffer *buf, Boolean freeData) 197 { 198 char *data = buf->buffer; 199 if (freeData) { 200 free(data); 201 data = NULL; 202 } 203 204 buf->size = 0; 205 buf->count = 0; 206 buf->buffer = NULL; 207 208 return data; 209 } 210 211 #ifndef BUF_COMPACT_LIMIT 212 # define BUF_COMPACT_LIMIT 128 /* worthwhile saving */ 213 #endif 214 215 /* Reset the buffer and return its data. 216 * 217 * If the buffer size is much greater than its content, 218 * a new buffer will be allocated and the old one freed. */ 219 char * 220 Buf_DestroyCompact(Buffer *buf) 221 { 222 #if BUF_COMPACT_LIMIT > 0 223 if (buf->size - buf->count >= BUF_COMPACT_LIMIT) { 224 /* We trust realloc to be smart */ 225 char *data = bmake_realloc(buf->buffer, buf->count + 1); 226 data[buf->count] = 0; 227 Buf_Destroy(buf, FALSE); 228 return data; 229 } 230 #endif 231 return Buf_Destroy(buf, FALSE); 232 } 233