1 /*- 2 * Copyright (c) 1986, 1988, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 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 * @(#)subr_prf.c 8.3 (Berkeley) 1/21/94 35 * $FreeBSD: src/sys/kern/subr_prf.c,v 1.61.2.5 2002/08/31 18:22:08 dwmalone Exp $ 36 */ 37 38 #include "opt_ddb.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/msgbuf.h> 44 #include <sys/malloc.h> 45 #include <sys/proc.h> 46 #include <sys/priv.h> 47 #include <sys/tty.h> 48 #include <sys/tprintf.h> 49 #include <sys/stdint.h> 50 #include <sys/syslog.h> 51 #include <sys/cons.h> 52 #include <sys/uio.h> 53 #include <sys/sysctl.h> 54 #include <sys/lock.h> 55 #include <sys/ctype.h> 56 #include <sys/eventhandler.h> 57 #include <sys/kthread.h> 58 59 #include <sys/thread2.h> 60 #include <sys/spinlock2.h> 61 62 #ifdef DDB 63 #include <ddb/ddb.h> 64 #endif 65 66 /* 67 * Note that stdarg.h and the ANSI style va_start macro is used for both 68 * ANSI and traditional C compilers. We use the __ machine version to stay 69 * within the kernel header file set. 70 */ 71 #include <machine/stdarg.h> 72 73 #define TOCONS 0x01 74 #define TOTTY 0x02 75 #define TOLOG 0x04 76 #define TOWAKEUP 0x08 77 78 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */ 79 #define MAXNBUF (sizeof(intmax_t) * NBBY + 1) 80 81 struct putchar_arg { 82 int flags; 83 int pri; 84 struct tty *tty; 85 }; 86 87 struct snprintf_arg { 88 char *str; 89 size_t remain; 90 }; 91 92 extern int log_open; 93 94 struct tty *constty; /* pointer to console "window" tty */ 95 96 static void msglogchar(int c, int pri); 97 static void msgaddchar(int c, void *dummy); 98 static void kputchar (int ch, void *arg); 99 static char *ksprintn (char *nbuf, uintmax_t num, int base, int *lenp, 100 int upper); 101 static void snprintf_func (int ch, void *arg); 102 103 static int consintr = 1; /* Ok to handle console interrupts? */ 104 static int msgbufmapped; /* Set when safe to use msgbuf */ 105 static struct spinlock cons_spin = SPINLOCK_INITIALIZER(cons_spin); 106 static thread_t constty_td = NULL; 107 108 int msgbuftrigger; 109 110 static int log_console_output = 1; 111 TUNABLE_INT("kern.log_console_output", &log_console_output); 112 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RW, 113 &log_console_output, 0, ""); 114 115 static int unprivileged_read_msgbuf = 1; 116 SYSCTL_INT(_security, OID_AUTO, unprivileged_read_msgbuf, CTLFLAG_RW, 117 &unprivileged_read_msgbuf, 0, 118 "Unprivileged processes may read the kernel message buffer"); 119 120 /* 121 * Warn that a system table is full. 122 */ 123 void 124 tablefull(const char *tab) 125 { 126 127 log(LOG_ERR, "%s: table is full\n", tab); 128 } 129 130 /* 131 * Uprintf prints to the controlling terminal for the current process. 132 */ 133 int 134 uprintf(const char *fmt, ...) 135 { 136 struct proc *p = curproc; 137 __va_list ap; 138 struct putchar_arg pca; 139 int retval = 0; 140 141 if (p && (p->p_flags & P_CONTROLT) && p->p_session->s_ttyvp) { 142 __va_start(ap, fmt); 143 pca.tty = p->p_session->s_ttyp; 144 pca.flags = TOTTY; 145 146 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 147 __va_end(ap); 148 } 149 return (retval); 150 } 151 152 tpr_t 153 tprintf_open(struct proc *p) 154 { 155 if ((p->p_flags & P_CONTROLT) && p->p_session->s_ttyvp) { 156 sess_hold(p->p_session); 157 return ((tpr_t) p->p_session); 158 } 159 return (NULL); 160 } 161 162 void 163 tprintf_close(tpr_t sess) 164 { 165 if (sess) 166 sess_rele((struct session *) sess); 167 } 168 169 /* 170 * tprintf prints on the controlling terminal associated 171 * with the given session. 172 */ 173 int 174 tprintf(tpr_t tpr, const char *fmt, ...) 175 { 176 struct session *sess = (struct session *)tpr; 177 struct tty *tp = NULL; 178 int flags = TOLOG; 179 __va_list ap; 180 struct putchar_arg pca; 181 int retval; 182 183 if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) { 184 flags |= TOTTY; 185 tp = sess->s_ttyp; 186 } 187 __va_start(ap, fmt); 188 pca.tty = tp; 189 pca.flags = flags; 190 pca.pri = LOG_INFO; 191 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 192 __va_end(ap); 193 msgbuftrigger = 1; 194 return (retval); 195 } 196 197 /* 198 * Ttyprintf displays a message on a tty; it should be used only by 199 * the tty driver, or anything that knows the underlying tty will not 200 * be revoke(2)'d away. Other callers should use tprintf. 201 */ 202 int 203 ttyprintf(struct tty *tp, const char *fmt, ...) 204 { 205 __va_list ap; 206 struct putchar_arg pca; 207 int retval; 208 209 __va_start(ap, fmt); 210 pca.tty = tp; 211 pca.flags = TOTTY; 212 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 213 __va_end(ap); 214 return (retval); 215 } 216 217 /* 218 * Log writes to the log buffer, and guarantees not to sleep (so can be 219 * called by interrupt routines). If there is no process reading the 220 * log yet, it writes to the console also. 221 */ 222 int 223 log(int level, const char *fmt, ...) 224 { 225 __va_list ap; 226 int retval; 227 struct putchar_arg pca; 228 229 pca.tty = NULL; 230 pca.pri = level; 231 pca.flags = log_open ? TOLOG : TOCONS; 232 233 __va_start(ap, fmt); 234 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 235 __va_end(ap); 236 237 msgbuftrigger = 1; 238 return (retval); 239 } 240 241 #define CONSCHUNK 128 242 243 void 244 log_console(struct uio *uio) 245 { 246 int c, i, error, iovlen, nl; 247 struct uio muio; 248 struct iovec *miov = NULL; 249 char *consbuffer; 250 int pri; 251 252 if (!log_console_output) 253 return; 254 255 pri = LOG_INFO | LOG_CONSOLE; 256 muio = *uio; 257 iovlen = uio->uio_iovcnt * sizeof (struct iovec); 258 miov = kmalloc(iovlen, M_TEMP, M_WAITOK); 259 consbuffer = kmalloc(CONSCHUNK, M_TEMP, M_WAITOK); 260 bcopy((caddr_t)muio.uio_iov, (caddr_t)miov, iovlen); 261 muio.uio_iov = miov; 262 uio = &muio; 263 264 nl = 0; 265 while (uio->uio_resid > 0) { 266 c = (int)szmin(uio->uio_resid, CONSCHUNK); 267 error = uiomove(consbuffer, (size_t)c, uio); 268 if (error != 0) 269 break; 270 for (i = 0; i < c; i++) { 271 msglogchar(consbuffer[i], pri); 272 if (consbuffer[i] == '\n') 273 nl = 1; 274 else 275 nl = 0; 276 } 277 } 278 if (!nl) 279 msglogchar('\n', pri); 280 msgbuftrigger = 1; 281 kfree(miov, M_TEMP); 282 kfree(consbuffer, M_TEMP); 283 return; 284 } 285 286 /* 287 * Output to the console. 288 */ 289 int 290 kprintf(const char *fmt, ...) 291 { 292 __va_list ap; 293 int savintr; 294 struct putchar_arg pca; 295 int retval; 296 297 savintr = consintr; /* disable interrupts */ 298 consintr = 0; 299 __va_start(ap, fmt); 300 pca.tty = NULL; 301 pca.flags = TOCONS | TOLOG; 302 pca.pri = -1; 303 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 304 __va_end(ap); 305 if (!panicstr) 306 msgbuftrigger = 1; 307 consintr = savintr; /* reenable interrupts */ 308 return (retval); 309 } 310 311 int 312 kvprintf(const char *fmt, __va_list ap) 313 { 314 int savintr; 315 struct putchar_arg pca; 316 int retval; 317 318 savintr = consintr; /* disable interrupts */ 319 consintr = 0; 320 pca.tty = NULL; 321 pca.flags = TOCONS | TOLOG; 322 pca.pri = -1; 323 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 324 if (!panicstr) 325 msgbuftrigger = 1; 326 consintr = savintr; /* reenable interrupts */ 327 return (retval); 328 } 329 330 /* 331 * Limited rate kprintf. The passed rate structure must be initialized 332 * with the desired reporting frequency. A frequency of 0 will result in 333 * no output. 334 * 335 * count may be initialized to a negative number to allow an initial 336 * burst. 337 */ 338 void 339 krateprintf(struct krate *rate, const char *fmt, ...) 340 { 341 __va_list ap; 342 343 if (rate->ticks != (int)time_uptime) { 344 rate->ticks = (int)time_uptime; 345 if (rate->count > 0) 346 rate->count = 0; 347 } 348 if (rate->count < rate->freq) { 349 ++rate->count; 350 __va_start(ap, fmt); 351 kvprintf(fmt, ap); 352 __va_end(ap); 353 } 354 } 355 356 /* 357 * Print a character to the dmesg log, the console, and/or the user's 358 * terminal. 359 * 360 * NOTE: TOTTY does not require nonblocking operation, but TOCONS 361 * and TOLOG do. When we have a constty we still output to 362 * the real console but we have a monitoring thread which 363 * we wakeup which tracks the log. 364 */ 365 static void 366 kputchar(int c, void *arg) 367 { 368 struct putchar_arg *ap = (struct putchar_arg*) arg; 369 int flags = ap->flags; 370 struct tty *tp = ap->tty; 371 372 if (panicstr) 373 constty = NULL; 374 if ((flags & TOCONS) && tp == NULL && constty) 375 flags |= TOLOG | TOWAKEUP; 376 if ((flags & TOTTY) && tputchar(c, tp) < 0) 377 ap->flags &= ~TOTTY; 378 if ((flags & TOLOG)) 379 msglogchar(c, ap->pri); 380 if ((flags & TOCONS) && c) 381 cnputc(c); 382 if (flags & TOWAKEUP) 383 wakeup(constty_td); 384 } 385 386 /* 387 * Scaled down version of sprintf(3). 388 */ 389 int 390 ksprintf(char *buf, const char *cfmt, ...) 391 { 392 int retval; 393 __va_list ap; 394 395 __va_start(ap, cfmt); 396 retval = kvcprintf(cfmt, NULL, buf, 10, ap); 397 buf[retval] = '\0'; 398 __va_end(ap); 399 return (retval); 400 } 401 402 /* 403 * Scaled down version of vsprintf(3). 404 */ 405 int 406 kvsprintf(char *buf, const char *cfmt, __va_list ap) 407 { 408 int retval; 409 410 retval = kvcprintf(cfmt, NULL, buf, 10, ap); 411 buf[retval] = '\0'; 412 return (retval); 413 } 414 415 /* 416 * Scaled down version of snprintf(3). 417 */ 418 int 419 ksnprintf(char *str, size_t size, const char *format, ...) 420 { 421 int retval; 422 __va_list ap; 423 424 __va_start(ap, format); 425 retval = kvsnprintf(str, size, format, ap); 426 __va_end(ap); 427 return(retval); 428 } 429 430 /* 431 * Scaled down version of vsnprintf(3). 432 */ 433 int 434 kvsnprintf(char *str, size_t size, const char *format, __va_list ap) 435 { 436 struct snprintf_arg info; 437 int retval; 438 439 info.str = str; 440 info.remain = size; 441 retval = kvcprintf(format, snprintf_func, &info, 10, ap); 442 if (info.remain >= 1) 443 *info.str++ = '\0'; 444 return (retval); 445 } 446 447 int 448 ksnrprintf(char *str, size_t size, int radix, const char *format, ...) 449 { 450 int retval; 451 __va_list ap; 452 453 __va_start(ap, format); 454 retval = kvsnrprintf(str, size, radix, format, ap); 455 __va_end(ap); 456 return(retval); 457 } 458 459 int 460 kvsnrprintf(char *str, size_t size, int radix, const char *format, __va_list ap) 461 { 462 struct snprintf_arg info; 463 int retval; 464 465 info.str = str; 466 info.remain = size; 467 retval = kvcprintf(format, snprintf_func, &info, radix, ap); 468 if (info.remain >= 1) 469 *info.str++ = '\0'; 470 return (retval); 471 } 472 473 int 474 kvasnrprintf(char **strp, size_t size, int radix, 475 const char *format, __va_list ap) 476 { 477 struct snprintf_arg info; 478 int retval; 479 480 *strp = kmalloc(size, M_TEMP, M_WAITOK); 481 info.str = *strp; 482 info.remain = size; 483 retval = kvcprintf(format, snprintf_func, &info, radix, ap); 484 if (info.remain >= 1) 485 *info.str++ = '\0'; 486 return (retval); 487 } 488 489 void 490 kvasfree(char **strp) 491 { 492 if (*strp) { 493 kfree(*strp, M_TEMP); 494 *strp = NULL; 495 } 496 } 497 498 static void 499 snprintf_func(int ch, void *arg) 500 { 501 struct snprintf_arg *const info = arg; 502 503 if (info->remain >= 2) { 504 *info->str++ = ch; 505 info->remain--; 506 } 507 } 508 509 /* 510 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse 511 * order; return an optional length and a pointer to the last character 512 * written in the buffer (i.e., the first character of the string). 513 * The buffer pointed to by `nbuf' must have length >= MAXNBUF. 514 */ 515 static char * 516 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper) 517 { 518 char *p, c; 519 520 p = nbuf; 521 *p = '\0'; 522 do { 523 c = hex2ascii(num % base); 524 *++p = upper ? toupper(c) : c; 525 } while (num /= base); 526 if (lenp) 527 *lenp = p - nbuf; 528 return (p); 529 } 530 531 /* 532 * Scaled down version of printf(3). 533 * 534 * Two additional formats: 535 * 536 * The format %b is supported to decode error registers. 537 * Its usage is: 538 * 539 * kprintf("reg=%b\n", regval, "<base><arg>*"); 540 * 541 * where <base> is the output base expressed as a control character, e.g. 542 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters, 543 * the first of which gives the bit number to be inspected (origin 1), and 544 * the next characters (up to a control character, i.e. a character <= 32), 545 * give the name of the register. Thus: 546 * 547 * kvcprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n"); 548 * 549 * would produce output: 550 * 551 * reg=3<BITTWO,BITONE> 552 */ 553 554 #define PCHAR(c) {int cc=(c); if(func) (*func)(cc,arg); else *d++=cc; retval++;} 555 556 int 557 kvcprintf(char const *fmt, void (*func)(int, void*), void *arg, 558 int radix, __va_list ap) 559 { 560 char nbuf[MAXNBUF]; 561 char *d; 562 const char *p, *percent, *q; 563 int ch, n; 564 uintmax_t num; 565 int base, tmp, width, ladjust, sharpflag, neg, sign, dot; 566 int cflag, hflag, jflag, lflag, qflag, tflag, zflag; 567 int dwidth, upper; 568 char padc; 569 int retval = 0, stop = 0; 570 int usespin; 571 572 /* 573 * Make a supreme effort to avoid reentrant panics or deadlocks. 574 * 575 * NOTE! Do nothing that would access mycpu/gd/fs unless the 576 * function is the normal kputchar(), which allows us to 577 * use this function for very early debugging with a special 578 * function. 579 */ 580 if (func == kputchar) { 581 if (mycpu->gd_flags & GDF_KPRINTF) 582 return(0); 583 atomic_set_long(&mycpu->gd_flags, GDF_KPRINTF); 584 } 585 586 num = 0; 587 if (!func) 588 d = (char *) arg; 589 else 590 d = NULL; 591 592 if (fmt == NULL) 593 fmt = "(fmt null)\n"; 594 595 if (radix < 2 || radix > 36) 596 radix = 10; 597 598 usespin = (func == kputchar && 599 panic_cpu_gd != mycpu && 600 (((struct putchar_arg *)arg)->flags & TOTTY) == 0); 601 if (usespin) { 602 crit_enter_hard(); 603 spin_lock(&cons_spin); 604 } 605 606 for (;;) { 607 padc = ' '; 608 width = 0; 609 while ((ch = (u_char)*fmt++) != '%' || stop) { 610 if (ch == '\0') 611 goto done; 612 PCHAR(ch); 613 } 614 percent = fmt - 1; 615 dot = dwidth = ladjust = neg = sharpflag = sign = upper = 0; 616 cflag = hflag = jflag = lflag = qflag = tflag = zflag = 0; 617 618 reswitch: 619 switch (ch = (u_char)*fmt++) { 620 case '.': 621 dot = 1; 622 goto reswitch; 623 case '#': 624 sharpflag = 1; 625 goto reswitch; 626 case '+': 627 sign = 1; 628 goto reswitch; 629 case '-': 630 ladjust = 1; 631 goto reswitch; 632 case '%': 633 PCHAR(ch); 634 break; 635 case '*': 636 if (!dot) { 637 width = __va_arg(ap, int); 638 if (width < 0) { 639 ladjust = !ladjust; 640 width = -width; 641 } 642 } else { 643 dwidth = __va_arg(ap, int); 644 } 645 goto reswitch; 646 case '0': 647 if (!dot) { 648 padc = '0'; 649 goto reswitch; 650 } 651 case '1': case '2': case '3': case '4': 652 case '5': case '6': case '7': case '8': case '9': 653 for (n = 0;; ++fmt) { 654 n = n * 10 + ch - '0'; 655 ch = *fmt; 656 if (ch < '0' || ch > '9') 657 break; 658 } 659 if (dot) 660 dwidth = n; 661 else 662 width = n; 663 goto reswitch; 664 case 'b': 665 num = (u_int)__va_arg(ap, int); 666 p = __va_arg(ap, char *); 667 for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;) 668 PCHAR(*q--); 669 670 if (num == 0) 671 break; 672 673 for (tmp = 0; *p;) { 674 n = *p++; 675 if (num & (1 << (n - 1))) { 676 PCHAR(tmp ? ',' : '<'); 677 for (; (n = *p) > ' '; ++p) 678 PCHAR(n); 679 tmp = 1; 680 } else 681 for (; *p > ' '; ++p) 682 continue; 683 } 684 if (tmp) 685 PCHAR('>'); 686 break; 687 case 'c': 688 PCHAR(__va_arg(ap, int)); 689 break; 690 case 'd': 691 case 'i': 692 base = 10; 693 sign = 1; 694 goto handle_sign; 695 case 'h': 696 if (hflag) { 697 hflag = 0; 698 cflag = 1; 699 } else 700 hflag = 1; 701 goto reswitch; 702 case 'j': 703 jflag = 1; 704 goto reswitch; 705 case 'l': 706 if (lflag) { 707 lflag = 0; 708 qflag = 1; 709 } else 710 lflag = 1; 711 goto reswitch; 712 case 'n': 713 if (cflag) 714 *(__va_arg(ap, char *)) = retval; 715 else if (hflag) 716 *(__va_arg(ap, short *)) = retval; 717 else if (jflag) 718 *(__va_arg(ap, intmax_t *)) = retval; 719 else if (lflag) 720 *(__va_arg(ap, long *)) = retval; 721 else if (qflag) 722 *(__va_arg(ap, quad_t *)) = retval; 723 else 724 *(__va_arg(ap, int *)) = retval; 725 break; 726 case 'o': 727 base = 8; 728 goto handle_nosign; 729 case 'p': 730 base = 16; 731 sharpflag = (width == 0); 732 sign = 0; 733 num = (uintptr_t)__va_arg(ap, void *); 734 goto number; 735 case 'q': 736 qflag = 1; 737 goto reswitch; 738 case 'r': 739 base = radix; 740 if (sign) 741 goto handle_sign; 742 goto handle_nosign; 743 case 's': 744 p = __va_arg(ap, char *); 745 if (p == NULL) 746 p = "(null)"; 747 if (!dot) 748 n = strlen (p); 749 else 750 for (n = 0; n < dwidth && p[n]; n++) 751 continue; 752 753 width -= n; 754 755 if (!ladjust && width > 0) 756 while (width--) 757 PCHAR(padc); 758 while (n--) 759 PCHAR(*p++); 760 if (ladjust && width > 0) 761 while (width--) 762 PCHAR(padc); 763 break; 764 case 't': 765 tflag = 1; 766 goto reswitch; 767 case 'u': 768 base = 10; 769 goto handle_nosign; 770 case 'X': 771 upper = 1; 772 /* FALLTHROUGH */ 773 case 'x': 774 base = 16; 775 goto handle_nosign; 776 case 'z': 777 zflag = 1; 778 goto reswitch; 779 handle_nosign: 780 sign = 0; 781 if (cflag) 782 num = (u_char)__va_arg(ap, int); 783 else if (hflag) 784 num = (u_short)__va_arg(ap, int); 785 else if (jflag) 786 num = __va_arg(ap, uintmax_t); 787 else if (lflag) 788 num = __va_arg(ap, u_long); 789 else if (qflag) 790 num = __va_arg(ap, u_quad_t); 791 else if (tflag) 792 num = __va_arg(ap, ptrdiff_t); 793 else if (zflag) 794 num = __va_arg(ap, size_t); 795 else 796 num = __va_arg(ap, u_int); 797 goto number; 798 handle_sign: 799 if (cflag) 800 num = (char)__va_arg(ap, int); 801 else if (hflag) 802 num = (short)__va_arg(ap, int); 803 else if (jflag) 804 num = __va_arg(ap, intmax_t); 805 else if (lflag) 806 num = __va_arg(ap, long); 807 else if (qflag) 808 num = __va_arg(ap, quad_t); 809 else if (tflag) 810 num = __va_arg(ap, ptrdiff_t); 811 else if (zflag) 812 num = __va_arg(ap, ssize_t); 813 else 814 num = __va_arg(ap, int); 815 number: 816 if (sign && (intmax_t)num < 0) { 817 neg = 1; 818 num = -(intmax_t)num; 819 } 820 p = ksprintn(nbuf, num, base, &n, upper); 821 tmp = 0; 822 if (sharpflag && num != 0) { 823 if (base == 8) 824 tmp++; 825 else if (base == 16) 826 tmp += 2; 827 } 828 if (neg) 829 tmp++; 830 831 if (!ladjust && padc == '0') 832 dwidth = width - tmp; 833 width -= tmp + imax(dwidth, n); 834 dwidth -= n; 835 if (!ladjust) 836 while (width-- > 0) 837 PCHAR(' '); 838 if (neg) 839 PCHAR('-'); 840 if (sharpflag && num != 0) { 841 if (base == 8) { 842 PCHAR('0'); 843 } else if (base == 16) { 844 PCHAR('0'); 845 PCHAR('x'); 846 } 847 } 848 while (dwidth-- > 0) 849 PCHAR('0'); 850 851 while (*p) 852 PCHAR(*p--); 853 854 if (ladjust) 855 while (width-- > 0) 856 PCHAR(' '); 857 858 break; 859 default: 860 while (percent < fmt) 861 PCHAR(*percent++); 862 /* 863 * Since we ignore an formatting argument it is no 864 * longer safe to obey the remaining formatting 865 * arguments as the arguments will no longer match 866 * the format specs. 867 */ 868 stop = 1; 869 break; 870 } 871 } 872 done: 873 /* 874 * Cleanup reentrancy issues. 875 */ 876 if (func == kputchar) 877 atomic_clear_long(&mycpu->gd_flags, GDF_KPRINTF); 878 if (usespin) { 879 spin_unlock(&cons_spin); 880 crit_exit_hard(); 881 } 882 return (retval); 883 } 884 885 #undef PCHAR 886 887 /* 888 * Called from the panic code to try to get the console working 889 * again in case we paniced inside a kprintf(). 890 */ 891 void 892 kvcreinitspin(void) 893 { 894 spin_init(&cons_spin); 895 atomic_clear_long(&mycpu->gd_flags, GDF_KPRINTF); 896 } 897 898 /* 899 * Console support thread for constty intercepts. This is needed because 900 * console tty intercepts can block. Instead of having kputchar() attempt 901 * to directly write to the console intercept we just force it to log 902 * and wakeup this baby to track and dump the log to constty. 903 */ 904 static void 905 constty_daemon(void) 906 { 907 int rindex = -1; 908 int windex = -1; 909 struct msgbuf *mbp; 910 struct tty *tp; 911 912 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, 913 constty_td, SHUTDOWN_PRI_FIRST); 914 constty_td->td_flags |= TDF_SYSTHREAD; 915 916 for (;;) { 917 kproc_suspend_loop(); 918 919 crit_enter(); 920 mbp = msgbufp; 921 if (mbp == NULL || msgbufmapped == 0 || 922 windex == mbp->msg_bufx) { 923 tsleep(constty_td, 0, "waiting", hz*60); 924 crit_exit(); 925 continue; 926 } 927 windex = mbp->msg_bufx; 928 crit_exit(); 929 930 /* 931 * Get message buf FIFO indices. rindex is tracking. 932 */ 933 if ((tp = constty) == NULL) { 934 rindex = mbp->msg_bufx; 935 continue; 936 } 937 938 /* 939 * Don't blow up if the message buffer is broken 940 */ 941 if (windex < 0 || windex >= mbp->msg_size) 942 continue; 943 if (rindex < 0 || rindex >= mbp->msg_size) 944 rindex = windex; 945 946 /* 947 * And dump it. If constty gets stuck will give up. 948 */ 949 while (rindex != windex) { 950 if (tputchar((uint8_t)mbp->msg_ptr[rindex], tp) < 0) { 951 constty = NULL; 952 rindex = mbp->msg_bufx; 953 break; 954 } 955 if (++rindex >= mbp->msg_size) 956 rindex = 0; 957 if (tp->t_outq.c_cc >= tp->t_ohiwat) { 958 tsleep(constty_daemon, 0, "blocked", hz / 10); 959 if (tp->t_outq.c_cc >= tp->t_ohiwat) { 960 rindex = windex; 961 break; 962 } 963 } 964 } 965 } 966 } 967 968 static struct kproc_desc constty_kp = { 969 "consttyd", 970 constty_daemon, 971 &constty_td 972 }; 973 SYSINIT(bufdaemon, SI_SUB_KTHREAD_UPDATE, SI_ORDER_ANY, 974 kproc_start, &constty_kp) 975 976 /* 977 * Put character in log buffer with a particular priority. 978 * 979 * MPSAFE 980 */ 981 static void 982 msglogchar(int c, int pri) 983 { 984 static int lastpri = -1; 985 static int dangling; 986 char nbuf[MAXNBUF]; 987 char *p; 988 989 if (!msgbufmapped) 990 return; 991 if (c == '\0' || c == '\r') 992 return; 993 if (pri != -1 && pri != lastpri) { 994 if (dangling) { 995 msgaddchar('\n', NULL); 996 dangling = 0; 997 } 998 msgaddchar('<', NULL); 999 for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;) 1000 msgaddchar(*p--, NULL); 1001 msgaddchar('>', NULL); 1002 lastpri = pri; 1003 } 1004 msgaddchar(c, NULL); 1005 if (c == '\n') { 1006 dangling = 0; 1007 lastpri = -1; 1008 } else { 1009 dangling = 1; 1010 } 1011 } 1012 1013 /* 1014 * Put char in log buffer. Make sure nothing blows up beyond repair if 1015 * we have an MP race. 1016 * 1017 * MPSAFE. 1018 */ 1019 static void 1020 msgaddchar(int c, void *dummy) 1021 { 1022 struct msgbuf *mbp; 1023 int rindex; 1024 int windex; 1025 1026 if (!msgbufmapped) 1027 return; 1028 mbp = msgbufp; 1029 windex = mbp->msg_bufx; 1030 mbp->msg_ptr[windex] = c; 1031 if (++windex >= mbp->msg_size) 1032 windex = 0; 1033 rindex = mbp->msg_bufr; 1034 if (windex == rindex) { 1035 rindex += 32; 1036 if (rindex >= mbp->msg_size) 1037 rindex -= mbp->msg_size; 1038 mbp->msg_bufr = rindex; 1039 } 1040 mbp->msg_bufx = windex; 1041 } 1042 1043 static void 1044 msgbufcopy(struct msgbuf *oldp) 1045 { 1046 int pos; 1047 1048 pos = oldp->msg_bufr; 1049 while (pos != oldp->msg_bufx) { 1050 msglogchar(oldp->msg_ptr[pos], -1); 1051 if (++pos >= oldp->msg_size) 1052 pos = 0; 1053 } 1054 } 1055 1056 void 1057 msgbufinit(void *ptr, size_t size) 1058 { 1059 char *cp; 1060 static struct msgbuf *oldp = NULL; 1061 1062 size -= sizeof(*msgbufp); 1063 cp = (char *)ptr; 1064 msgbufp = (struct msgbuf *) (cp + size); 1065 if (msgbufp->msg_magic != MSG_MAGIC || msgbufp->msg_size != size || 1066 msgbufp->msg_bufx >= size || msgbufp->msg_bufr >= size) { 1067 bzero(cp, size); 1068 bzero(msgbufp, sizeof(*msgbufp)); 1069 msgbufp->msg_magic = MSG_MAGIC; 1070 msgbufp->msg_size = (char *)msgbufp - cp; 1071 } 1072 msgbufp->msg_ptr = cp; 1073 if (msgbufmapped && oldp != msgbufp) 1074 msgbufcopy(oldp); 1075 msgbufmapped = 1; 1076 oldp = msgbufp; 1077 } 1078 1079 /* Sysctls for accessing/clearing the msgbuf */ 1080 1081 static int 1082 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS) 1083 { 1084 struct ucred *cred; 1085 int error; 1086 1087 /* 1088 * Only wheel or root can access the message log. 1089 */ 1090 if (unprivileged_read_msgbuf == 0) { 1091 KKASSERT(req->td->td_proc); 1092 cred = req->td->td_proc->p_ucred; 1093 1094 if ((cred->cr_prison || groupmember(0, cred) == 0) && 1095 priv_check(req->td, PRIV_ROOT) != 0 1096 ) { 1097 return (EPERM); 1098 } 1099 } 1100 1101 /* 1102 * Unwind the buffer, so that it's linear (possibly starting with 1103 * some initial nulls). 1104 */ 1105 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr + msgbufp->msg_bufx, 1106 msgbufp->msg_size - msgbufp->msg_bufx, req); 1107 if (error) 1108 return (error); 1109 if (msgbufp->msg_bufx > 0) { 1110 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr, 1111 msgbufp->msg_bufx, req); 1112 } 1113 return (error); 1114 } 1115 1116 SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD, 1117 0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer"); 1118 1119 static int msgbuf_clear; 1120 1121 static int 1122 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS) 1123 { 1124 int error; 1125 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req); 1126 if (!error && req->newptr) { 1127 /* Clear the buffer and reset write pointer */ 1128 bzero(msgbufp->msg_ptr, msgbufp->msg_size); 1129 msgbufp->msg_bufr = msgbufp->msg_bufx = 0; 1130 msgbuf_clear = 0; 1131 } 1132 return (error); 1133 } 1134 1135 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear, 1136 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clear, 0, 1137 sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer"); 1138 1139 #ifdef DDB 1140 1141 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf) 1142 { 1143 int i, j; 1144 1145 if (!msgbufmapped) { 1146 db_printf("msgbuf not mapped yet\n"); 1147 return; 1148 } 1149 db_printf("msgbufp = %p\n", msgbufp); 1150 db_printf("magic = %x, size = %d, r= %d, w = %d, ptr = %p\n", 1151 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_bufr, 1152 msgbufp->msg_bufx, msgbufp->msg_ptr); 1153 for (i = 0; i < msgbufp->msg_size; i++) { 1154 j = (i + msgbufp->msg_bufr) % msgbufp->msg_size; 1155 db_printf("%c", msgbufp->msg_ptr[j]); 1156 } 1157 db_printf("\n"); 1158 } 1159 1160 #endif /* DDB */ 1161 1162 1163 void 1164 hexdump(const void *ptr, int length, const char *hdr, int flags) 1165 { 1166 int i, j, k; 1167 int cols; 1168 const unsigned char *cp; 1169 char delim; 1170 1171 if ((flags & HD_DELIM_MASK) != 0) 1172 delim = (flags & HD_DELIM_MASK) >> 8; 1173 else 1174 delim = ' '; 1175 1176 if ((flags & HD_COLUMN_MASK) != 0) 1177 cols = flags & HD_COLUMN_MASK; 1178 else 1179 cols = 16; 1180 1181 cp = ptr; 1182 for (i = 0; i < length; i+= cols) { 1183 if (hdr != NULL) 1184 kprintf("%s", hdr); 1185 1186 if ((flags & HD_OMIT_COUNT) == 0) 1187 kprintf("%04x ", i); 1188 1189 if ((flags & HD_OMIT_HEX) == 0) { 1190 for (j = 0; j < cols; j++) { 1191 k = i + j; 1192 if (k < length) 1193 kprintf("%c%02x", delim, cp[k]); 1194 else 1195 kprintf(" "); 1196 } 1197 } 1198 1199 if ((flags & HD_OMIT_CHARS) == 0) { 1200 kprintf(" |"); 1201 for (j = 0; j < cols; j++) { 1202 k = i + j; 1203 if (k >= length) 1204 kprintf(" "); 1205 else if (cp[k] >= ' ' && cp[k] <= '~') 1206 kprintf("%c", cp[k]); 1207 else 1208 kprintf("."); 1209 } 1210 kprintf("|"); 1211 } 1212 kprintf("\n"); 1213 } 1214 } 1215