2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1986, 1988, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)subr_prf.c 8.3 (Berkeley) 1/21/94
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
44 #include "opt_printf.h"
47 #include <sys/param.h>
49 #include <sys/systm.h>
52 #include <sys/mutex.h>
54 #include <sys/kernel.h>
55 #include <sys/msgbuf.h>
56 #include <sys/malloc.h>
59 #include <sys/stddef.h>
60 #include <sys/sysctl.h>
62 #include <sys/syslog.h>
66 #include <sys/ctype.h>
74 * Note that stdarg.h and the ANSI style va_start macro is used for both
75 * ANSI and traditional C compilers.
78 #include <machine/stdarg.h>
84 * This is needed for sbuf_putbuf() when compiled into userland. Due to the
85 * shared nature of this file, it's the only place to put it.
97 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
98 #define MAXNBUF (sizeof(intmax_t) * NBBY + 1)
110 struct snprintf_arg {
117 static void msglogchar(int c, int pri);
118 static void msglogstr(char *str, int pri, int filter_cr);
119 static void putchar(int ch, void *arg);
120 static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
121 static void snprintf_func(int ch, void *arg);
123 static int msgbufmapped; /* Set when safe to use msgbuf */
126 static int log_console_output = 1;
127 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RWTUN,
128 &log_console_output, 0, "Duplicate console output to the syslog");
131 * See the comment in log_console() below for more explanation of this.
133 static int log_console_add_linefeed;
134 SYSCTL_INT(_kern, OID_AUTO, log_console_add_linefeed, CTLFLAG_RWTUN,
135 &log_console_add_linefeed, 0, "log_console() adds extra newlines");
137 static int always_console_output;
138 SYSCTL_INT(_kern, OID_AUTO, always_console_output, CTLFLAG_RWTUN,
139 &always_console_output, 0, "Always output to console despite TIOCCONS");
142 * Warn that a system table is full.
145 tablefull(const char *tab)
148 log(LOG_ERR, "%s: table is full\n", tab);
152 * Uprintf prints to the controlling terminal for the current process.
155 uprintf(const char *fmt, ...)
158 struct putchar_arg pca;
164 if (TD_IS_IDLETHREAD(td))
167 sx_slock(&proctree_lock);
170 if ((p->p_flag & P_CONTROLT) == 0) {
172 sx_sunlock(&proctree_lock);
175 SESS_LOCK(p->p_session);
176 pca.tty = p->p_session->s_ttyp;
177 SESS_UNLOCK(p->p_session);
179 if (pca.tty == NULL) {
180 sx_sunlock(&proctree_lock);
187 sx_sunlock(&proctree_lock);
188 retval = kvprintf(fmt, putchar, &pca, 10, ap);
195 * tprintf and vtprintf print on the controlling terminal associated with the
196 * given session, possibly to the log as well.
199 tprintf(struct proc *p, int pri, const char *fmt, ...)
204 vtprintf(p, pri, fmt, ap);
209 vtprintf(struct proc *p, int pri, const char *fmt, va_list ap)
211 struct tty *tp = NULL;
213 struct putchar_arg pca;
214 struct session *sess = NULL;
216 sx_slock(&proctree_lock);
221 if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
226 if (tp != NULL && tty_checkoutq(tp))
239 sx_sunlock(&proctree_lock);
240 kvprintf(fmt, putchar, &pca, 10, ap);
249 * Ttyprintf displays a message on a tty; it should be used only by
250 * the tty driver, or anything that knows the underlying tty will not
251 * be revoke(2)'d away. Other callers should use tprintf.
254 ttyprintf(struct tty *tp, const char *fmt, ...)
257 struct putchar_arg pca;
264 retval = kvprintf(fmt, putchar, &pca, 10, ap);
270 _vprintf(int level, int flags, const char *fmt, va_list ap)
272 struct putchar_arg pca;
274 #ifdef PRINTF_BUFR_SIZE
275 char bufr[PRINTF_BUFR_SIZE];
281 #ifdef PRINTF_BUFR_SIZE
283 pca.p_next = pca.p_bufr;
284 pca.n_bufr = sizeof(bufr);
285 pca.remain = sizeof(bufr);
288 /* Don't buffer console output. */
292 retval = kvprintf(fmt, putchar, &pca, 10, ap);
294 #ifdef PRINTF_BUFR_SIZE
295 /* Write any buffered console/log output: */
296 if (*pca.p_bufr != '\0') {
297 if (pca.flags & TOLOG)
298 msglogstr(pca.p_bufr, level, /*filter_cr*/1);
300 if (pca.flags & TOCONS)
309 * Log writes to the log buffer, and guarantees not to sleep (so can be
310 * called by interrupt routines). If there is no process reading the
311 * log yet, it writes to the console also.
314 log(int level, const char *fmt, ...)
319 vlog(level, fmt, ap);
324 vlog(int level, const char *fmt, va_list ap)
327 (void)_vprintf(level, log_open ? TOLOG : TOCONS | TOLOG, fmt, ap);
331 #define CONSCHUNK 128
334 log_console(struct uio *uio)
340 if (!log_console_output)
343 pri = LOG_INFO | LOG_CONSOLE;
345 consbuffer = malloc(CONSCHUNK, M_TEMP, M_WAITOK);
348 while (uio->uio_resid > 0) {
349 c = imin(uio->uio_resid, CONSCHUNK - 1);
350 error = uiomove(consbuffer, c, uio);
353 /* Make sure we're NUL-terminated */
354 consbuffer[c] = '\0';
355 if (consbuffer[c - 1] == '\n')
359 msglogstr(consbuffer, pri, /*filter_cr*/ 1);
362 * The previous behavior in log_console() is preserved when
363 * log_console_add_linefeed is non-zero. For that behavior, if an
364 * individual console write came in that was not terminated with a
365 * line feed, it would add a line feed.
367 * This results in different data in the message buffer than
368 * appears on the system console (which doesn't add extra line feed
371 * A number of programs and rc scripts write a line feed, or a period
372 * and a line feed when they have completed their operation. On
373 * the console, this looks seamless, but when displayed with
374 * 'dmesg -a', you wind up with output that looks like this:
379 * On the console, it looks like this:
382 * We could add logic to detect that situation, or just not insert
383 * the extra newlines. Set the kern.log_console_add_linefeed
384 * sysctl/tunable variable to get the old behavior.
386 if (!nl && log_console_add_linefeed) {
387 consbuffer[0] = '\n';
388 consbuffer[1] = '\0';
389 msglogstr(consbuffer, pri, /*filter_cr*/ 1);
393 free(consbuffer, M_TEMP);
397 printf(const char *fmt, ...)
403 retval = vprintf(fmt, ap);
410 vprintf(const char *fmt, va_list ap)
414 retval = _vprintf(-1, TOCONS | TOLOG, fmt, ap);
423 prf_putbuf(char *bufr, int flags, int pri)
427 msglogstr(bufr, pri, /*filter_cr*/1);
429 if (flags & TOCONS) {
430 if ((panicstr == NULL) && (constty != NULL))
431 msgbuf_addstr(&consmsgbuf, -1,
432 bufr, /*filter_cr*/ 0);
434 if ((constty == NULL) ||(always_console_output))
440 putbuf(int c, struct putchar_arg *ap)
442 /* Check if no console output buffer was provided. */
443 if (ap->p_bufr == NULL) {
444 /* Output direct to the console. */
445 if (ap->flags & TOCONS)
448 if (ap->flags & TOLOG)
449 msglogchar(c, ap->pri);
451 /* Buffer the character: */
455 /* Always leave the buffer zero terminated. */
458 /* Check if the buffer needs to be flushed. */
459 if (ap->remain == 2 || c == '\n') {
460 prf_putbuf(ap->p_bufr, ap->flags, ap->pri);
462 ap->p_next = ap->p_bufr;
463 ap->remain = ap->n_bufr;
468 * Since we fill the buffer up one character at a time,
469 * this should not happen. We should always catch it when
470 * ap->remain == 2 (if not sooner due to a newline), flush
471 * the buffer and move on. One way this could happen is
472 * if someone sets PRINTF_BUFR_SIZE to 1 or something
475 KASSERT(ap->remain > 2, ("Bad buffer logic, remain = %zd",
481 * Print a character on console or users terminal. If destination is
482 * the console then the last bunch of characters are saved in msgbuf for
486 putchar(int c, void *arg)
488 struct putchar_arg *ap = (struct putchar_arg*) arg;
489 struct tty *tp = ap->tty;
490 int flags = ap->flags;
492 /* Don't use the tty code after a panic or while in ddb. */
499 if ((flags & TOTTY) && tp != NULL && panicstr == NULL)
502 if ((flags & (TOCONS | TOLOG)) && c != '\0')
507 * Scaled down version of sprintf(3).
510 sprintf(char *buf, const char *cfmt, ...)
516 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
523 * Scaled down version of vsprintf(3).
526 vsprintf(char *buf, const char *cfmt, va_list ap)
530 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
536 * Scaled down version of snprintf(3).
539 snprintf(char *str, size_t size, const char *format, ...)
544 va_start(ap, format);
545 retval = vsnprintf(str, size, format, ap);
551 * Scaled down version of vsnprintf(3).
554 vsnprintf(char *str, size_t size, const char *format, va_list ap)
556 struct snprintf_arg info;
561 retval = kvprintf(format, snprintf_func, &info, 10, ap);
562 if (info.remain >= 1)
568 * Kernel version which takes radix argument vsnprintf(3).
571 vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
573 struct snprintf_arg info;
578 retval = kvprintf(format, snprintf_func, &info, radix, ap);
579 if (info.remain >= 1)
585 snprintf_func(int ch, void *arg)
587 struct snprintf_arg *const info = arg;
589 if (info->remain >= 2) {
596 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
597 * order; return an optional length and a pointer to the last character
598 * written in the buffer (i.e., the first character of the string).
599 * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
602 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
609 c = hex2ascii(num % base);
610 *++p = upper ? toupper(c) : c;
611 } while (num /= base);
618 * Scaled down version of printf(3).
620 * Two additional formats:
622 * The format %b is supported to decode error registers.
625 * printf("reg=%b\n", regval, "<base><arg>*");
627 * where <base> is the output base expressed as a control character, e.g.
628 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters,
629 * the first of which gives the bit number to be inspected (origin 1), and
630 * the next characters (up to a control character, i.e. a character <= 32),
631 * give the name of the register. Thus:
633 * kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
635 * would produce output:
637 * reg=3<BITTWO,BITONE>
639 * XXX: %D -- Hexdump, takes pointer and separator string:
640 * ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX
641 * ("%*D", len, ptr, " " -> XX XX XX XX ...
644 kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
646 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
649 const char *p, *percent, *q;
653 int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
654 int cflag, hflag, jflag, tflag, zflag;
655 int bconv, dwidth, upper;
657 int stop = 0, retval = 0;
666 fmt = "(fmt null)\n";
668 if (radix < 2 || radix > 36)
674 while ((ch = (u_char)*fmt++) != '%' || stop) {
680 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
681 sign = 0; dot = 0; bconv = 0; dwidth = 0; upper = 0;
682 cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
683 reswitch: switch (ch = (u_char)*fmt++) {
701 width = va_arg(ap, int);
707 dwidth = va_arg(ap, int);
715 case '1': case '2': case '3': case '4':
716 case '5': case '6': case '7': case '8': case '9':
717 for (n = 0;; ++fmt) {
718 n = n * 10 + ch - '0';
720 if (ch < '0' || ch > '9')
735 if (!ladjust && width > 0)
738 PCHAR(va_arg(ap, int));
739 if (ladjust && width > 0)
744 up = va_arg(ap, u_char *);
745 p = va_arg(ap, char *);
749 PCHAR(hex2ascii(*up >> 4));
750 PCHAR(hex2ascii(*up & 0x0f));
781 *(va_arg(ap, intmax_t *)) = retval;
783 *(va_arg(ap, quad_t *)) = retval;
785 *(va_arg(ap, long *)) = retval;
787 *(va_arg(ap, size_t *)) = retval;
789 *(va_arg(ap, short *)) = retval;
791 *(va_arg(ap, char *)) = retval;
793 *(va_arg(ap, int *)) = retval;
800 sharpflag = (width == 0);
802 num = (uintptr_t)va_arg(ap, void *);
813 p = va_arg(ap, char *);
819 for (n = 0; n < dwidth && p[n]; n++)
824 if (!ladjust && width > 0)
829 if (ladjust && width > 0)
854 num = va_arg(ap, uintmax_t);
856 num = va_arg(ap, u_quad_t);
858 num = va_arg(ap, ptrdiff_t);
860 num = va_arg(ap, u_long);
862 num = va_arg(ap, size_t);
864 num = (u_short)va_arg(ap, int);
866 num = (u_char)va_arg(ap, int);
868 num = va_arg(ap, u_int);
870 q = va_arg(ap, char *);
876 num = va_arg(ap, intmax_t);
878 num = va_arg(ap, quad_t);
880 num = va_arg(ap, ptrdiff_t);
882 num = va_arg(ap, long);
884 num = va_arg(ap, ssize_t);
886 num = (short)va_arg(ap, int);
888 num = (char)va_arg(ap, int);
890 num = va_arg(ap, int);
892 if (sign && (intmax_t)num < 0) {
894 num = -(intmax_t)num;
896 p = ksprintn(nbuf, num, base, &n, upper);
898 if (sharpflag && num != 0) {
907 if (!ladjust && padc == '0')
908 dwidth = width - tmp;
909 width -= tmp + imax(dwidth, n);
916 if (sharpflag && num != 0) {
919 } else if (base == 16) {
930 if (bconv && num != 0) {
931 /* %b conversion flag format. */
935 if (num & (1 << (n - 1))) {
936 PCHAR(retval != tmp ?
938 for (; (n = *q) > ' '; ++q)
941 for (; *q > ' '; ++q)
946 width -= retval - tmp;
956 while (percent < fmt)
959 * Since we ignore a formatting argument it is no
960 * longer safe to obey the remaining formatting
961 * arguments as the arguments will no longer match
972 * Put character in log buffer with a particular priority.
975 msglogchar(int c, int pri)
977 static int lastpri = -1;
984 if (c == '\0' || c == '\r')
986 if (pri != -1 && pri != lastpri) {
988 msgbuf_addchar(msgbufp, '\n');
991 msgbuf_addchar(msgbufp, '<');
992 for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;)
993 msgbuf_addchar(msgbufp, *p--);
994 msgbuf_addchar(msgbufp, '>');
997 msgbuf_addchar(msgbufp, c);
1007 msglogstr(char *str, int pri, int filter_cr)
1012 msgbuf_addstr(msgbufp, pri, str, filter_cr);
1016 msgbufinit(void *ptr, int size)
1019 static struct msgbuf *oldp = NULL;
1021 size -= sizeof(*msgbufp);
1023 msgbufp = (struct msgbuf *)(cp + size);
1024 msgbuf_reinit(msgbufp, cp, size);
1025 if (msgbufmapped && oldp != msgbufp)
1026 msgbuf_copy(oldp, msgbufp);
1031 static int unprivileged_read_msgbuf = 1;
1032 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf,
1033 CTLFLAG_RW, &unprivileged_read_msgbuf, 0,
1034 "Unprivileged processes may read the kernel message buffer");
1036 /* Sysctls for accessing/clearing the msgbuf */
1038 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
1044 if (!unprivileged_read_msgbuf) {
1045 error = priv_check(req->td, PRIV_MSGBUF);
1050 /* Read the whole buffer, one chunk at a time. */
1051 mtx_lock(&msgbuf_lock);
1052 msgbuf_peekbytes(msgbufp, NULL, 0, &seq);
1054 len = msgbuf_peekbytes(msgbufp, buf, sizeof(buf), &seq);
1055 mtx_unlock(&msgbuf_lock);
1057 return (SYSCTL_OUT(req, "", 1)); /* add nulterm */
1059 error = sysctl_handle_opaque(oidp, buf, len, req);
1063 mtx_lock(&msgbuf_lock);
1067 SYSCTL_PROC(_kern, OID_AUTO, msgbuf,
1068 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
1069 NULL, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
1071 static int msgbuf_clearflag;
1074 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
1077 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
1078 if (!error && req->newptr) {
1079 mtx_lock(&msgbuf_lock);
1080 msgbuf_clear(msgbufp);
1081 mtx_unlock(&msgbuf_lock);
1082 msgbuf_clearflag = 0;
1087 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
1088 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE,
1089 &msgbuf_clearflag, 0, sysctl_kern_msgbuf_clear, "I",
1090 "Clear kernel message buffer");
1094 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
1098 if (!msgbufmapped) {
1099 db_printf("msgbuf not mapped yet\n");
1102 db_printf("msgbufp = %p\n", msgbufp);
1103 db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
1104 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
1105 msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
1106 for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
1107 j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
1108 db_printf("%c", msgbufp->msg_ptr[j]);
1116 hexdump(const void *ptr, int length, const char *hdr, int flags)
1120 const unsigned char *cp;
1123 if ((flags & HD_DELIM_MASK) != 0)
1124 delim = (flags & HD_DELIM_MASK) >> 8;
1128 if ((flags & HD_COLUMN_MASK) != 0)
1129 cols = flags & HD_COLUMN_MASK;
1134 for (i = 0; i < length; i+= cols) {
1138 if ((flags & HD_OMIT_COUNT) == 0)
1141 if ((flags & HD_OMIT_HEX) == 0) {
1142 for (j = 0; j < cols; j++) {
1145 printf("%c%02x", delim, cp[k]);
1151 if ((flags & HD_OMIT_CHARS) == 0) {
1153 for (j = 0; j < cols; j++) {
1157 else if (cp[k] >= ' ' && cp[k] <= '~')
1158 printf("%c", cp[k]);
1167 #endif /* _KERNEL */
1170 sbuf_hexdump(struct sbuf *sb, const void *ptr, int length, const char *hdr,
1175 const unsigned char *cp;
1178 if ((flags & HD_DELIM_MASK) != 0)
1179 delim = (flags & HD_DELIM_MASK) >> 8;
1183 if ((flags & HD_COLUMN_MASK) != 0)
1184 cols = flags & HD_COLUMN_MASK;
1189 for (i = 0; i < length; i+= cols) {
1191 sbuf_printf(sb, "%s", hdr);
1193 if ((flags & HD_OMIT_COUNT) == 0)
1194 sbuf_printf(sb, "%04x ", i);
1196 if ((flags & HD_OMIT_HEX) == 0) {
1197 for (j = 0; j < cols; j++) {
1200 sbuf_printf(sb, "%c%02x", delim, cp[k]);
1202 sbuf_printf(sb, " ");
1206 if ((flags & HD_OMIT_CHARS) == 0) {
1207 sbuf_printf(sb, " |");
1208 for (j = 0; j < cols; j++) {
1211 sbuf_printf(sb, " ");
1212 else if (cp[k] >= ' ' && cp[k] <= '~')
1213 sbuf_printf(sb, "%c", cp[k]);
1215 sbuf_printf(sb, ".");
1217 sbuf_printf(sb, "|");
1219 sbuf_printf(sb, "\n");
1225 counted_warning(unsigned *counter, const char *msg)
1234 if (atomic_cmpset_int(counter, c, c - 1)) {
1236 log(LOG_INFO, "pid %d (%s) %s%s\n",
1237 td->td_proc->p_pid, td->td_name, msg,
1238 c > 1 ? "" : " - not logging anymore");
1247 sbuf_putbuf(struct sbuf *sb)
1250 prf_putbuf(sbuf_data(sb), TOLOG | TOCONS, -1);
1254 sbuf_putbuf(struct sbuf *sb)
1257 printf("%s", sbuf_data(sb));