snprintb.c revision 1.5.6.1 1 /* $NetBSD: snprintb.c,v 1.5.6.1 2012/04/17 00:01:40 yamt 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 1.5.6.1 2012/04/17 00:01:40 yamt Exp $");
45 # endif
46
47 # include <sys/types.h>
48 # include <sys/inttypes.h>
49 # include <stdio.h>
50 # include <util.h>
51 # include <errno.h>
52 # else
53 # include <sys/cdefs.h>
54 __KERNEL_RCSID(0, "$NetBSD: snprintb.c,v 1.5.6.1 2012/04/17 00:01:40 yamt Exp $");
55 # include <sys/param.h>
56 # include <sys/inttypes.h>
57 # include <sys/systm.h>
58 # include <lib/libkern/libkern.h>
59 # endif
60
61 int
62 snprintb_m(char *buf, size_t buflen, const char *bitfmt, uint64_t val,
63 size_t l_max)
64 {
65 char *bp = buf, *s_bp = NULL;
66 const char *c_fmt, *s_fmt = NULL, *cur_fmt;
67 const char *sbase;
68 int bit, ch, t_len, s_len = 0, l_len, f_len, v_len, sep;
69 int restart = 0;
70 uint64_t field;
71
72 #ifdef _KERNEL
73 /*
74 * For safety; no other *s*printf() do this, but in the kernel
75 * we don't usually check the return value
76 */
77 (void)memset(buf, 0, buflen);
78 #endif /* _KERNEL */
79
80 ch = *bitfmt++;
81 switch (ch != '\177' ? ch : *bitfmt++) {
82 case 8:
83 sbase = "0%" PRIo64;
84 break;
85 case 10:
86 sbase = "%" PRId64;
87 break;
88 case 16:
89 sbase = "0x%" PRIx64;
90 break;
91 default:
92 goto internal;
93 }
94
95 /* Reserve space for trailing blank line if needed */
96 if (l_max > 0)
97 buflen--;
98
99 t_len = snprintf(bp, buflen, sbase, val);
100 if (t_len < 0)
101 goto internal;
102
103 v_len = l_len = t_len;
104
105 if ((size_t)t_len < buflen)
106 bp += t_len;
107 else
108 bp += buflen - 1;
109
110 /*
111 * If the value we printed was 0 and we're using the old-style format,
112 * we're done.
113 */
114 if ((val == 0) && (ch != '\177'))
115 goto terminate;
116
117 #define STORE(c) { l_len++; \
118 if ((size_t)(++t_len) < buflen) \
119 *bp++ = (c); \
120 } while ( /* CONSTCOND */ 0)
121
122 #define BACKUP { if (s_bp != NULL) { \
123 bp = s_bp; s_bp = NULL; \
124 t_len -= l_len - s_len; \
125 restart = 1; \
126 bitfmt = s_fmt; \
127 } \
128 STORE('>'); STORE('\0'); \
129 if ((size_t)t_len < buflen) \
130 snprintf(bp, buflen - t_len, sbase, val); \
131 t_len += v_len; l_len = v_len; bp += v_len; \
132 } while ( /* CONSTCOND */ 0)
133
134 #define PUTSEP \
135 if (l_max > 0 && (size_t)l_len >= l_max) { \
136 BACKUP; \
137 STORE('<'); \
138 } else { \
139 /* Remember separator location */ \
140 if (l_max > 0 && sep != '<') { \
141 s_len = l_len; \
142 s_bp = bp; \
143 s_fmt = cur_fmt; \
144 } \
145 STORE(sep); \
146 restart = 0; \
147 } \
148
149 #define PUTCHR(c) \
150 if (l_max > 0 && (size_t)l_len >= (l_max - 1)) { \
151 BACKUP; \
152 if (restart == 0) { \
153 STORE(c); \
154 } else \
155 sep = '<'; \
156 } else { \
157 STORE(c); \
158 restart = 0; \
159 } \
160
161 #define PUTS(s) while ((ch = *(s)++) != 0) { \
162 PUTCHR(ch); \
163 if (restart) \
164 break; \
165 }
166
167 /*
168 * Chris Torek's new bitmask format is identified by a leading \177
169 */
170 sep = '<';
171 if (ch != '\177') {
172 /* old (standard) format. */
173 for (;(bit = *bitfmt) != 0;) {
174 cur_fmt = bitfmt++;
175 if (val & (1 << (bit - 1))) {
176 PUTSEP;
177 if (restart)
178 continue;
179 sep = ',';
180 for (; (ch = *bitfmt) > ' '; ++bitfmt) {
181 PUTCHR(ch);
182 if (restart)
183 break;
184 }
185 } else
186 for (; *bitfmt > ' '; ++bitfmt)
187 continue;
188 }
189 } else {
190 /* new quad-capable format; also does fields. */
191 field = val;
192 while (c_fmt = bitfmt, (ch = *bitfmt++) != '\0') {
193 bit = *bitfmt++; /* now 0-origin */
194 switch (ch) {
195 case 'b':
196 if (((u_int)(val >> bit) & 1) == 0)
197 goto skip;
198 cur_fmt = c_fmt;
199 PUTSEP;
200 if (restart)
201 break;
202 PUTS(bitfmt);
203 if (restart == 0)
204 sep = ',';
205 break;
206 case 'f':
207 case 'F':
208 cur_fmt = c_fmt;
209 f_len = *bitfmt++; /* field length */
210 field = (val >> bit) &
211 (((uint64_t)1 << f_len) - 1);
212 PUTSEP;
213 if (restart == 0)
214 sep = ',';
215 if (ch == 'F') /* just extract */
216 break;
217 if (restart == 0) {
218 PUTS(bitfmt);
219 PUTCHR('=');
220 }
221 if (restart == 0) {
222 f_len = snprintf(bp, buflen - t_len,
223 sbase, field);
224 if (f_len < 0)
225 goto internal;
226 t_len += f_len;
227 l_len += f_len;
228 if ((size_t)t_len < buflen)
229 bp += f_len;
230 if (l_max > 0 &&
231 (size_t)l_len > l_max) {
232 PUTCHR('#');
233 }
234 }
235 break;
236 case '=':
237 case ':':
238 /*
239 * Here "bit" is actually a value instead,
240 * to be compared against the last field.
241 * This only works for values in [0..255],
242 * of course.
243 */
244 if ((int)field != bit)
245 goto skip;
246 if (ch == '=') {
247 PUTCHR('=');
248 }
249 PUTS(bitfmt);
250 break;
251 default:
252 skip:
253 while (*bitfmt++ != '\0')
254 continue;
255 break;
256 }
257 }
258 }
259 l_len++;
260 if ((size_t)(++t_len) < buflen)
261 *bp++ = '>';
262 terminate:
263 *bp++ = '\0';
264 if (l_max != 0) {
265 t_len++;
266 *bp = '\0';
267 }
268 return t_len;
269 internal:
270 #ifndef _KERNEL
271 errno = EINVAL;
272 #endif
273 return -1;
274 }
275
276 int
277 snprintb(char *buf, size_t buflen, const char *bitfmt, uint64_t val)
278 {
279 return snprintb_m(buf, buflen, bitfmt, val, 0);
280 }
281 #endif
282