snprintb.c revision 1.18
1 /* $NetBSD: snprintb.c,v 1.18 2018/07/26 00:33:26 kamil Exp $ */ 2 3 /*- 4 * Copyright (c) 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * snprintb: print an interpreted bitmask to a buffer 31 * 32 * => returns the length of the buffer that would be required to print the 33 * string minus the terminating NUL. 34 */ 35 #ifndef _STANDALONE 36 # ifndef _KERNEL 37 38 # if HAVE_NBTOOL_CONFIG_H 39 # include "nbtool_config.h" 40 # endif 41 42 # include <sys/cdefs.h> 43 # if defined(LIBC_SCCS) && !defined(lint) 44 __RCSID("$NetBSD: snprintb.c,v 1.18 2018/07/26 00:33:26 kamil Exp $"); 45 # endif 46 47 # include <sys/types.h> 48 # include <inttypes.h> 49 # include <stdio.h> 50 # include <util.h> 51 # include <errno.h> 52 # else /* ! _KERNEL */ 53 # include <sys/cdefs.h> 54 __KERNEL_RCSID(0, "$NetBSD: snprintb.c,v 1.18 2018/07/26 00:33:26 kamil Exp $"); 55 # include <sys/param.h> 56 # include <sys/inttypes.h> 57 # include <sys/systm.h> 58 # include <lib/libkern/libkern.h> 59 # endif /* ! _KERNEL */ 60 61 # ifndef HAVE_SNPRINTB_M 62 int 63 snprintb_m(char *buf, size_t buflen, const char *bitfmt, uint64_t val, 64 size_t l_max) 65 { 66 char *bp = buf, *s_bp = NULL; 67 const char *c_fmt, *s_fmt = NULL, *cur_fmt; 68 const char *sbase; 69 int bit, ch, t_len, s_len = 0, l_len, f_len, v_len, sep; 70 int restart = 0; 71 uint64_t field; 72 73 #ifdef _KERNEL 74 /* 75 * For safety; no other *s*printf() do this, but in the kernel 76 * we don't usually check the return value 77 */ 78 (void)memset(buf, 0, buflen); 79 #endif /* _KERNEL */ 80 81 ch = *bitfmt++; 82 switch (ch != '\177' ? ch : *bitfmt++) { 83 case 8: 84 sbase = "0%" PRIo64; 85 break; 86 case 10: 87 sbase = "%" PRId64; 88 break; 89 case 16: 90 sbase = "0x%" PRIx64; 91 break; 92 default: 93 goto internal; 94 } 95 96 /* Reserve space for trailing blank line if needed */ 97 if (l_max > 0) 98 buflen--; 99 100 t_len = snprintf(bp, buflen, sbase, val); 101 if (t_len < 0) 102 goto internal; 103 104 v_len = l_len = t_len; 105 106 if ((size_t)t_len < buflen) 107 bp += t_len; 108 else 109 bp += buflen - 1; 110 111 /* 112 * If the value we printed was 0 and we're using the old-style format, 113 * we're done. 114 */ 115 if ((val == 0) && (ch != '\177')) 116 goto terminate; 117 118 #define STORE(c) do { l_len++; \ 119 if ((size_t)(++t_len) < buflen) \ 120 *bp++ = (c); \ 121 } while ( /* CONSTCOND */ 0) 122 123 #define BACKUP do { if (s_bp != NULL) { \ 124 bp = s_bp; s_bp = NULL; \ 125 t_len -= l_len - s_len; \ 126 restart = 1; \ 127 bitfmt = s_fmt; \ 128 } \ 129 STORE('>'); STORE('\0'); \ 130 if ((size_t)t_len < buflen) \ 131 snprintf(bp, buflen - t_len, sbase, val); \ 132 t_len += v_len; l_len = v_len; bp += v_len; \ 133 } while ( /* CONSTCOND */ 0) 134 135 #define PUTSEP do { \ 136 if (l_max > 0 && (size_t)l_len >= l_max) { \ 137 BACKUP; \ 138 STORE('<'); \ 139 } else { \ 140 /* Remember separator location */ \ 141 if (l_max > 0 && sep != '<') { \ 142 s_len = l_len; \ 143 s_bp = bp; \ 144 s_fmt = cur_fmt; \ 145 } \ 146 STORE(sep); \ 147 restart = 0; \ 148 } \ 149 } while ( /* CONSTCOND */ 0) 150 151 #define PUTCHR(c) do { \ 152 if (l_max > 0 && (size_t)l_len >= (l_max - 1)) {\ 153 BACKUP; \ 154 if (restart == 0) \ 155 STORE(c); \ 156 else \ 157 sep = '<'; \ 158 } else { \ 159 STORE(c); \ 160 restart = 0; \ 161 } \ 162 } while ( /* CONSTCOND */ 0) 163 164 #define PUTS(s) while ((ch = *(s)++) != 0) { \ 165 PUTCHR(ch); \ 166 if (restart) \ 167 break; \ 168 } 169 170 /* 171 * Chris Torek's new bitmask format is identified by a leading \177 172 */ 173 sep = '<'; 174 if (ch != '\177') { 175 /* old (standard) format. */ 176 for (;(bit = *bitfmt) != 0;) { 177 cur_fmt = bitfmt++; 178 if (val & (1U << (bit - 1))) { 179 PUTSEP; 180 if (restart) 181 continue; 182 sep = ','; 183 for (; (ch = *bitfmt) > ' '; ++bitfmt) { 184 PUTCHR(ch); 185 if (restart) 186 break; 187 } 188 } else 189 for (; *bitfmt > ' '; ++bitfmt) 190 continue; 191 } 192 } else { 193 /* new quad-capable format; also does fields. */ 194 field = val; 195 while (c_fmt = bitfmt, (ch = *bitfmt++) != '\0') { 196 bit = *bitfmt++; /* now 0-origin */ 197 switch (ch) { 198 case 'b': 199 if (((unsigned int)(val >> bit) & 1) == 0) 200 goto skip; 201 cur_fmt = c_fmt; 202 PUTSEP; 203 if (restart) 204 break; 205 PUTS(bitfmt); 206 if (restart == 0) 207 sep = ','; 208 break; 209 case 'f': 210 case 'F': 211 cur_fmt = c_fmt; 212 f_len = *bitfmt++; /* field length */ 213 field = (val >> bit) & 214 (((uint64_t)1 << f_len) - 1); 215 PUTSEP; 216 if (restart == 0) 217 sep = ','; 218 if (ch == 'F') { /* just extract */ 219 bitfmt--; 220 break; 221 } 222 if (restart == 0) 223 PUTS(bitfmt); 224 if (restart == 0) 225 PUTCHR('='); 226 if (restart == 0) { 227 f_len = snprintf(bp, buflen - t_len, 228 sbase, field); 229 if (f_len < 0) 230 goto internal; 231 t_len += f_len; 232 l_len += f_len; 233 if ((size_t)t_len < buflen) 234 bp += f_len; 235 if (l_max > 0 && (size_t)l_len > l_max) 236 PUTCHR('#'); 237 } 238 break; 239 case '=': 240 case ':': 241 /* 242 * Here "bit" is actually a value instead, 243 * to be compared against the last field. 244 * This only works for values in [0..255], 245 * of course. 246 */ 247 if ((int)field != bit) 248 goto skip; 249 if (ch == '=') 250 PUTCHR('='); 251 PUTS(bitfmt); 252 break; 253 default: 254 skip: 255 while (*bitfmt++ != '\0') 256 continue; 257 break; 258 } 259 } 260 } 261 l_len++; 262 if (sep != '<' && (size_t)(++t_len) < buflen) 263 *bp++ = '>'; 264 terminate: 265 *bp++ = '\0'; 266 if (l_max != 0) { 267 t_len++; 268 *bp = '\0'; 269 } 270 return t_len; 271 internal: 272 #ifndef _KERNEL 273 errno = EINVAL; 274 #endif 275 return -1; 276 } 277 278 int 279 snprintb(char *buf, size_t buflen, const char *bitfmt, uint64_t val) 280 { 281 return snprintb_m(buf, buflen, bitfmt, val, 0); 282 } 283 # endif /* ! HAVE_SNPRINTB_M */ 284 #endif /* ! _STANDALONE */ 285
Indexes created Sun Sep 21 18:09:52 GMT 2025