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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)subr_prf.c 8.3 (Berkeley) 1/21/94 39 * $FreeBSD: src/sys/kern/subr_prf.c,v 1.61.2.5 2002/08/31 18:22:08 dwmalone Exp $ 40 */ 41 42 #include "opt_ddb.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/msgbuf.h> 48 #include <sys/malloc.h> 49 #include <sys/proc.h> 50 #include <sys/priv.h> 51 #include <sys/tty.h> 52 #include <sys/tprintf.h> 53 #include <sys/stdint.h> 54 #include <sys/syslog.h> 55 #include <sys/cons.h> 56 #include <sys/uio.h> 57 #include <sys/sysctl.h> 58 #include <sys/lock.h> 59 #include <sys/ctype.h> 60 #include <sys/eventhandler.h> 61 #include <sys/kthread.h> 62 63 #include <sys/thread2.h> 64 #include <sys/spinlock2.h> 65 66 #ifdef DDB 67 #include <ddb/ddb.h> 68 #endif 69 70 /* 71 * Note that stdarg.h and the ANSI style va_start macro is used for both 72 * ANSI and traditional C compilers. We use the __ machine version to stay 73 * within the kernel header file set. 74 */ 75 #include <machine/stdarg.h> 76 77 #define TOCONS 0x01 78 #define TOTTY 0x02 79 #define TOLOG 0x04 80 #define TOWAKEUP 0x08 81 82 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */ 83 #define MAXNBUF (sizeof(intmax_t) * NBBY + 1) 84 85 struct putchar_arg { 86 int flags; 87 int pri; 88 struct tty *tty; 89 }; 90 91 struct snprintf_arg { 92 char *str; 93 size_t remain; 94 }; 95 96 extern int log_open; 97 98 struct tty *constty; /* pointer to console "window" tty */ 99 100 static void msglogchar(int c, int pri); 101 static void msgaddchar(int c, void *dummy); 102 static void kputchar (int ch, void *arg); 103 static char *ksprintn (char *nbuf, uintmax_t num, int base, int *lenp, 104 int upper); 105 static void snprintf_func (int ch, void *arg); 106 107 static int consintr = 1; /* Ok to handle console interrupts? */ 108 static int msgbufmapped; /* Set when safe to use msgbuf */ 109 static struct spinlock cons_spin = SPINLOCK_INITIALIZER(cons_spin); 110 static thread_t constty_td = NULL; 111 112 int msgbuftrigger; 113 114 static int log_console_output = 1; 115 TUNABLE_INT("kern.log_console_output", &log_console_output); 116 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RW, 117 &log_console_output, 0, ""); 118 119 static int unprivileged_read_msgbuf = 1; 120 SYSCTL_INT(_security, OID_AUTO, unprivileged_read_msgbuf, CTLFLAG_RW, 121 &unprivileged_read_msgbuf, 0, 122 "Unprivileged processes may read the kernel message buffer"); 123 124 /* 125 * Warn that a system table is full. 126 */ 127 void 128 tablefull(const char *tab) 129 { 130 131 log(LOG_ERR, "%s: table is full\n", tab); 132 } 133 134 /* 135 * Uprintf prints to the controlling terminal for the current process. 136 */ 137 int 138 uprintf(const char *fmt, ...) 139 { 140 struct proc *p = curproc; 141 __va_list ap; 142 struct putchar_arg pca; 143 int retval = 0; 144 145 if (p && (p->p_flags & P_CONTROLT) && p->p_session->s_ttyvp) { 146 __va_start(ap, fmt); 147 pca.tty = p->p_session->s_ttyp; 148 pca.flags = TOTTY; 149 150 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 151 __va_end(ap); 152 } 153 return (retval); 154 } 155 156 tpr_t 157 tprintf_open(struct proc *p) 158 { 159 if ((p->p_flags & P_CONTROLT) && p->p_session->s_ttyvp) { 160 sess_hold(p->p_session); 161 return ((tpr_t) p->p_session); 162 } 163 return (NULL); 164 } 165 166 void 167 tprintf_close(tpr_t sess) 168 { 169 if (sess) 170 sess_rele((struct session *) sess); 171 } 172 173 /* 174 * tprintf prints on the controlling terminal associated 175 * with the given session. 176 */ 177 int 178 tprintf(tpr_t tpr, const char *fmt, ...) 179 { 180 struct session *sess = (struct session *)tpr; 181 struct tty *tp = NULL; 182 int flags = TOLOG; 183 __va_list ap; 184 struct putchar_arg pca; 185 int retval; 186 187 if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) { 188 flags |= TOTTY; 189 tp = sess->s_ttyp; 190 } 191 __va_start(ap, fmt); 192 pca.tty = tp; 193 pca.flags = flags; 194 pca.pri = LOG_INFO; 195 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 196 __va_end(ap); 197 msgbuftrigger = 1; 198 return (retval); 199 } 200 201 /* 202 * Ttyprintf displays a message on a tty; it should be used only by 203 * the tty driver, or anything that knows the underlying tty will not 204 * be revoke(2)'d away. Other callers should use tprintf. 205 */ 206 int 207 ttyprintf(struct tty *tp, const char *fmt, ...) 208 { 209 __va_list ap; 210 struct putchar_arg pca; 211 int retval; 212 213 __va_start(ap, fmt); 214 pca.tty = tp; 215 pca.flags = TOTTY; 216 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 217 __va_end(ap); 218 return (retval); 219 } 220 221 /* 222 * Log writes to the log buffer, and guarantees not to sleep (so can be 223 * called by interrupt routines). If there is no process reading the 224 * log yet, it writes to the console also. 225 */ 226 int 227 log(int level, const char *fmt, ...) 228 { 229 __va_list ap; 230 int retval; 231 struct putchar_arg pca; 232 233 pca.tty = NULL; 234 pca.pri = level; 235 pca.flags = log_open ? TOLOG : TOCONS; 236 237 __va_start(ap, fmt); 238 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 239 __va_end(ap); 240 241 msgbuftrigger = 1; 242 return (retval); 243 } 244 245 #define CONSCHUNK 128 246 247 void 248 log_console(struct uio *uio) 249 { 250 int c, i, error, iovlen, nl; 251 struct uio muio; 252 struct iovec *miov = NULL; 253 char *consbuffer; 254 int pri; 255 256 if (!log_console_output) 257 return; 258 259 pri = LOG_INFO | LOG_CONSOLE; 260 muio = *uio; 261 iovlen = uio->uio_iovcnt * sizeof (struct iovec); 262 miov = kmalloc(iovlen, M_TEMP, M_WAITOK); 263 consbuffer = kmalloc(CONSCHUNK, M_TEMP, M_WAITOK); 264 bcopy((caddr_t)muio.uio_iov, (caddr_t)miov, iovlen); 265 muio.uio_iov = miov; 266 uio = &muio; 267 268 nl = 0; 269 while (uio->uio_resid > 0) { 270 c = (int)szmin(uio->uio_resid, CONSCHUNK); 271 error = uiomove(consbuffer, (size_t)c, uio); 272 if (error != 0) 273 break; 274 for (i = 0; i < c; i++) { 275 msglogchar(consbuffer[i], pri); 276 if (consbuffer[i] == '\n') 277 nl = 1; 278 else 279 nl = 0; 280 } 281 } 282 if (!nl) 283 msglogchar('\n', pri); 284 msgbuftrigger = 1; 285 kfree(miov, M_TEMP); 286 kfree(consbuffer, M_TEMP); 287 return; 288 } 289 290 /* 291 * Output to the console. 292 */ 293 int 294 kprintf(const char *fmt, ...) 295 { 296 __va_list ap; 297 int savintr; 298 struct putchar_arg pca; 299 int retval; 300 301 savintr = consintr; /* disable interrupts */ 302 consintr = 0; 303 __va_start(ap, fmt); 304 pca.tty = NULL; 305 pca.flags = TOCONS | TOLOG; 306 pca.pri = -1; 307 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 308 __va_end(ap); 309 if (!panicstr) 310 msgbuftrigger = 1; 311 consintr = savintr; /* reenable interrupts */ 312 return (retval); 313 } 314 315 int 316 kvprintf(const char *fmt, __va_list ap) 317 { 318 int savintr; 319 struct putchar_arg pca; 320 int retval; 321 322 savintr = consintr; /* disable interrupts */ 323 consintr = 0; 324 pca.tty = NULL; 325 pca.flags = TOCONS | TOLOG; 326 pca.pri = -1; 327 retval = kvcprintf(fmt, kputchar, &pca, 10, ap); 328 if (!panicstr) 329 msgbuftrigger = 1; 330 consintr = savintr; /* reenable interrupts */ 331 return (retval); 332 } 333 334 /* 335 * Limited rate kprintf. The passed rate structure must be initialized 336 * with the desired reporting frequency. A frequency of 0 will result in 337 * no output. 338 * 339 * count may be initialized to a negative number to allow an initial 340 * burst. 341 */ 342 void 343 krateprintf(struct krate *rate, const char *fmt, ...) 344 { 345 __va_list ap; 346 347 if (rate->ticks != (int)time_second) { 348 rate->ticks = (int)time_second; 349 if (rate->count > 0) 350 rate->count = 0; 351 } 352 if (rate->count < rate->freq) { 353 ++rate->count; 354 __va_start(ap, fmt); 355 kvprintf(fmt, ap); 356 __va_end(ap); 357 } 358 } 359 360 /* 361 * Print a character to the dmesg log, the console, and/or the user's 362 * terminal. 363 * 364 * NOTE: TOTTY does not require nonblocking operation, but TOCONS 365 * and TOLOG do. When we have a constty we still output to 366 * the real console but we have a monitoring thread which 367 * we wakeup which tracks the log. 368 */ 369 static void 370 kputchar(int c, void *arg) 371 { 372 struct putchar_arg *ap = (struct putchar_arg*) arg; 373 int flags = ap->flags; 374 struct tty *tp = ap->tty; 375 376 if (panicstr) 377 constty = NULL; 378 if ((flags & TOCONS) && tp == NULL && constty) 379 flags |= TOLOG | TOWAKEUP; 380 if ((flags & TOTTY) && tputchar(c, tp) < 0) 381 ap->flags &= ~TOTTY; 382 if ((flags & TOLOG)) 383 msglogchar(c, ap->pri); 384 if ((flags & TOCONS) && c) 385 cnputc(c); 386 if (flags & TOWAKEUP) 387 wakeup(constty_td); 388 } 389 390 /* 391 * Scaled down version of sprintf(3). 392 */ 393 int 394 ksprintf(char *buf, const char *cfmt, ...) 395 { 396 int retval; 397 __va_list ap; 398 399 __va_start(ap, cfmt); 400 retval = kvcprintf(cfmt, NULL, buf, 10, ap); 401 buf[retval] = '\0'; 402 __va_end(ap); 403 return (retval); 404 } 405 406 /* 407 * Scaled down version of vsprintf(3). 408 */ 409 int 410 kvsprintf(char *buf, const char *cfmt, __va_list ap) 411 { 412 int retval; 413 414 retval = kvcprintf(cfmt, NULL, buf, 10, ap); 415 buf[retval] = '\0'; 416 return (retval); 417 } 418 419 /* 420 * Scaled down version of snprintf(3). 421 */ 422 int 423 ksnprintf(char *str, size_t size, const char *format, ...) 424 { 425 int retval; 426 __va_list ap; 427 428 __va_start(ap, format); 429 retval = kvsnprintf(str, size, format, ap); 430 __va_end(ap); 431 return(retval); 432 } 433 434 /* 435 * Scaled down version of vsnprintf(3). 436 */ 437 int 438 kvsnprintf(char *str, size_t size, const char *format, __va_list ap) 439 { 440 struct snprintf_arg info; 441 int retval; 442 443 info.str = str; 444 info.remain = size; 445 retval = kvcprintf(format, snprintf_func, &info, 10, ap); 446 if (info.remain >= 1) 447 *info.str++ = '\0'; 448 return (retval); 449 } 450 451 int 452 ksnrprintf(char *str, size_t size, int radix, const char *format, ...) 453 { 454 int retval; 455 __va_list ap; 456 457 __va_start(ap, format); 458 retval = kvsnrprintf(str, size, radix, format, ap); 459 __va_end(ap); 460 return(retval); 461 } 462 463 int 464 kvsnrprintf(char *str, size_t size, int radix, const char *format, __va_list ap) 465 { 466 struct snprintf_arg info; 467 int retval; 468 469 info.str = str; 470 info.remain = size; 471 retval = kvcprintf(format, snprintf_func, &info, radix, ap); 472 if (info.remain >= 1) 473 *info.str++ = '\0'; 474 return (retval); 475 } 476 477 int 478 kvasnrprintf(char **strp, size_t size, int radix, 479 const char *format, __va_list ap) 480 { 481 struct snprintf_arg info; 482 int retval; 483 484 *strp = kmalloc(size, M_TEMP, M_WAITOK); 485 info.str = *strp; 486 info.remain = size; 487 retval = kvcprintf(format, snprintf_func, &info, radix, ap); 488 if (info.remain >= 1) 489 *info.str++ = '\0'; 490 return (retval); 491 } 492 493 void 494 kvasfree(char **strp) 495 { 496 if (*strp) { 497 kfree(*strp, M_TEMP); 498 *strp = NULL; 499 } 500 } 501 502 static void 503 snprintf_func(int ch, void *arg) 504 { 505 struct snprintf_arg *const info = arg; 506 507 if (info->remain >= 2) { 508 *info->str++ = ch; 509 info->remain--; 510 } 511 } 512 513 /* 514 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse 515 * order; return an optional length and a pointer to the last character 516 * written in the buffer (i.e., the first character of the string). 517 * The buffer pointed to by `nbuf' must have length >= MAXNBUF. 518 */ 519 static char * 520 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper) 521 { 522 char *p, c; 523 524 p = nbuf; 525 *p = '\0'; 526 do { 527 c = hex2ascii(num % base); 528 *++p = upper ? toupper(c) : c; 529 } while (num /= base); 530 if (lenp) 531 *lenp = p - nbuf; 532 return (p); 533 } 534 535 /* 536 * Scaled down version of printf(3). 537 * 538 * Two additional formats: 539 * 540 * The format %b is supported to decode error registers. 541 * Its usage is: 542 * 543 * kprintf("reg=%b\n", regval, "<base><arg>*"); 544 * 545 * where <base> is the output base expressed as a control character, e.g. 546 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters, 547 * the first of which gives the bit number to be inspected (origin 1), and 548 * the next characters (up to a control character, i.e. a character <= 32), 549 * give the name of the register. Thus: 550 * 551 * kvcprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n"); 552 * 553 * would produce output: 554 * 555 * reg=3<BITTWO,BITONE> 556 * 557 * XXX: %D -- Hexdump, takes pointer and separator string: 558 * ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX 559 * ("%*D", len, ptr, " " -> XX XX XX XX ... 560 */ 561 562 #define PCHAR(c) {int cc=(c); if(func) (*func)(cc,arg); else *d++=cc; retval++;} 563 564 int 565 kvcprintf(char const *fmt, void (*func)(int, void*), void *arg, 566 int radix, __va_list ap) 567 { 568 char nbuf[MAXNBUF]; 569 char *d; 570 const char *p, *percent, *q; 571 int ch, n; 572 uintmax_t num; 573 int base, tmp, width, ladjust, sharpflag, neg, sign, dot; 574 int cflag, hflag, jflag, lflag, qflag, tflag, zflag; 575 int dwidth, upper; 576 char padc; 577 int retval = 0, stop = 0; 578 int usespin; 579 580 /* 581 * Make a supreme effort to avoid reentrant panics or deadlocks. 582 * 583 * NOTE! Do nothing that would access mycpu/gd/fs unless the 584 * function is the normal kputchar(), which allows us to 585 * use this function for very early debugging with a special 586 * function. 587 */ 588 if (func == kputchar) { 589 if (mycpu->gd_flags & GDF_KPRINTF) 590 return(0); 591 atomic_set_long(&mycpu->gd_flags, GDF_KPRINTF); 592 } 593 594 num = 0; 595 if (!func) 596 d = (char *) arg; 597 else 598 d = NULL; 599 600 if (fmt == NULL) 601 fmt = "(fmt null)\n"; 602 603 if (radix < 2 || radix > 36) 604 radix = 10; 605 606 usespin = (func == kputchar && 607 panic_cpu_gd != mycpu && 608 (((struct putchar_arg *)arg)->flags & TOTTY) == 0); 609 if (usespin) { 610 crit_enter_hard(); 611 spin_lock(&cons_spin); 612 } 613 614 for (;;) { 615 padc = ' '; 616 width = 0; 617 while ((ch = (u_char)*fmt++) != '%' || stop) { 618 if (ch == '\0') 619 goto done; 620 PCHAR(ch); 621 } 622 percent = fmt - 1; 623 dot = dwidth = ladjust = neg = sharpflag = sign = upper = 0; 624 cflag = hflag = jflag = lflag = qflag = tflag = zflag = 0; 625 626 reswitch: 627 switch (ch = (u_char)*fmt++) { 628 case '.': 629 dot = 1; 630 goto reswitch; 631 case '#': 632 sharpflag = 1; 633 goto reswitch; 634 case '+': 635 sign = 1; 636 goto reswitch; 637 case '-': 638 ladjust = 1; 639 goto reswitch; 640 case '%': 641 PCHAR(ch); 642 break; 643 case '*': 644 if (!dot) { 645 width = __va_arg(ap, int); 646 if (width < 0) { 647 ladjust = !ladjust; 648 width = -width; 649 } 650 } else { 651 dwidth = __va_arg(ap, int); 652 } 653 goto reswitch; 654 case '0': 655 if (!dot) { 656 padc = '0'; 657 goto reswitch; 658 } 659 case '1': case '2': case '3': case '4': 660 case '5': case '6': case '7': case '8': case '9': 661 for (n = 0;; ++fmt) { 662 n = n * 10 + ch - '0'; 663 ch = *fmt; 664 if (ch < '0' || ch > '9') 665 break; 666 } 667 if (dot) 668 dwidth = n; 669 else 670 width = n; 671 goto reswitch; 672 case 'b': 673 num = (u_int)__va_arg(ap, int); 674 p = __va_arg(ap, char *); 675 for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;) 676 PCHAR(*q--); 677 678 if (num == 0) 679 break; 680 681 for (tmp = 0; *p;) { 682 n = *p++; 683 if (num & (1 << (n - 1))) { 684 PCHAR(tmp ? ',' : '<'); 685 for (; (n = *p) > ' '; ++p) 686 PCHAR(n); 687 tmp = 1; 688 } else 689 for (; *p > ' '; ++p) 690 continue; 691 } 692 if (tmp) 693 PCHAR('>'); 694 break; 695 case 'c': 696 PCHAR(__va_arg(ap, int)); 697 break; 698 case 'd': 699 case 'i': 700 base = 10; 701 sign = 1; 702 goto handle_sign; 703 case 'h': 704 if (hflag) { 705 hflag = 0; 706 cflag = 1; 707 } else 708 hflag = 1; 709 goto reswitch; 710 case 'j': 711 jflag = 1; 712 goto reswitch; 713 case 'l': 714 if (lflag) { 715 lflag = 0; 716 qflag = 1; 717 } else 718 lflag = 1; 719 goto reswitch; 720 case 'n': 721 if (cflag) 722 *(__va_arg(ap, char *)) = retval; 723 else if (hflag) 724 *(__va_arg(ap, short *)) = retval; 725 else if (jflag) 726 *(__va_arg(ap, intmax_t *)) = retval; 727 else if (lflag) 728 *(__va_arg(ap, long *)) = retval; 729 else if (qflag) 730 *(__va_arg(ap, quad_t *)) = retval; 731 else 732 *(__va_arg(ap, int *)) = retval; 733 break; 734 case 'o': 735 base = 8; 736 goto handle_nosign; 737 case 'p': 738 base = 16; 739 sharpflag = (width == 0); 740 sign = 0; 741 num = (uintptr_t)__va_arg(ap, void *); 742 goto number; 743 case 'q': 744 qflag = 1; 745 goto reswitch; 746 case 'r': 747 base = radix; 748 if (sign) 749 goto handle_sign; 750 goto handle_nosign; 751 case 's': 752 p = __va_arg(ap, char *); 753 if (p == NULL) 754 p = "(null)"; 755 if (!dot) 756 n = strlen (p); 757 else 758 for (n = 0; n < dwidth && p[n]; n++) 759 continue; 760 761 width -= n; 762 763 if (!ladjust && width > 0) 764 while (width--) 765 PCHAR(padc); 766 while (n--) 767 PCHAR(*p++); 768 if (ladjust && width > 0) 769 while (width--) 770 PCHAR(padc); 771 break; 772 case 't': 773 tflag = 1; 774 goto reswitch; 775 case 'u': 776 base = 10; 777 goto handle_nosign; 778 case 'X': 779 upper = 1; 780 /* FALLTHROUGH */ 781 case 'x': 782 base = 16; 783 goto handle_nosign; 784 case 'z': 785 zflag = 1; 786 goto reswitch; 787 handle_nosign: 788 sign = 0; 789 if (cflag) 790 num = (u_char)__va_arg(ap, int); 791 else if (hflag) 792 num = (u_short)__va_arg(ap, int); 793 else if (jflag) 794 num = __va_arg(ap, uintmax_t); 795 else if (lflag) 796 num = __va_arg(ap, u_long); 797 else if (qflag) 798 num = __va_arg(ap, u_quad_t); 799 else if (tflag) 800 num = __va_arg(ap, ptrdiff_t); 801 else if (zflag) 802 num = __va_arg(ap, size_t); 803 else 804 num = __va_arg(ap, u_int); 805 goto number; 806 handle_sign: 807 if (cflag) 808 num = (char)__va_arg(ap, int); 809 else if (hflag) 810 num = (short)__va_arg(ap, int); 811 else if (jflag) 812 num = __va_arg(ap, intmax_t); 813 else if (lflag) 814 num = __va_arg(ap, long); 815 else if (qflag) 816 num = __va_arg(ap, quad_t); 817 else if (tflag) 818 num = __va_arg(ap, ptrdiff_t); 819 else if (zflag) 820 num = __va_arg(ap, ssize_t); 821 else 822 num = __va_arg(ap, int); 823 number: 824 if (sign && (intmax_t)num < 0) { 825 neg = 1; 826 num = -(intmax_t)num; 827 } 828 p = ksprintn(nbuf, num, base, &n, upper); 829 tmp = 0; 830 if (sharpflag && num != 0) { 831 if (base == 8) 832 tmp++; 833 else if (base == 16) 834 tmp += 2; 835 } 836 if (neg) 837 tmp++; 838 839 if (!ladjust && padc == '0') 840 dwidth = width - tmp; 841 width -= tmp + imax(dwidth, n); 842 dwidth -= n; 843 if (!ladjust) 844 while (width-- > 0) 845 PCHAR(' '); 846 if (neg) 847 PCHAR('-'); 848 if (sharpflag && num != 0) { 849 if (base == 8) { 850 PCHAR('0'); 851 } else if (base == 16) { 852 PCHAR('0'); 853 PCHAR('x'); 854 } 855 } 856 while (dwidth-- > 0) 857 PCHAR('0'); 858 859 while (*p) 860 PCHAR(*p--); 861 862 if (ladjust) 863 while (width-- > 0) 864 PCHAR(' '); 865 866 break; 867 default: 868 while (percent < fmt) 869 PCHAR(*percent++); 870 /* 871 * Since we ignore an formatting argument it is no 872 * longer safe to obey the remaining formatting 873 * arguments as the arguments will no longer match 874 * the format specs. 875 */ 876 stop = 1; 877 break; 878 } 879 } 880 done: 881 /* 882 * Cleanup reentrancy issues. 883 */ 884 if (func == kputchar) 885 atomic_clear_long(&mycpu->gd_flags, GDF_KPRINTF); 886 if (usespin) { 887 spin_unlock(&cons_spin); 888 crit_exit_hard(); 889 } 890 return (retval); 891 } 892 893 #undef PCHAR 894 895 /* 896 * Called from the panic code to try to get the console working 897 * again in case we paniced inside a kprintf(). 898 */ 899 void 900 kvcreinitspin(void) 901 { 902 spin_init(&cons_spin); 903 atomic_clear_long(&mycpu->gd_flags, GDF_KPRINTF); 904 } 905 906 /* 907 * Console support thread for constty intercepts. This is needed because 908 * console tty intercepts can block. Instead of having kputchar() attempt 909 * to directly write to the console intercept we just force it to log 910 * and wakeup this baby to track and dump the log to constty. 911 */ 912 static void 913 constty_daemon(void) 914 { 915 int rindex = -1; 916 int windex = -1; 917 struct msgbuf *mbp; 918 struct tty *tp; 919 920 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, 921 constty_td, SHUTDOWN_PRI_FIRST); 922 constty_td->td_flags |= TDF_SYSTHREAD; 923 924 for (;;) { 925 kproc_suspend_loop(); 926 927 crit_enter(); 928 mbp = msgbufp; 929 if (mbp == NULL || msgbufmapped == 0 || 930 windex == mbp->msg_bufx) { 931 tsleep(constty_td, 0, "waiting", hz*60); 932 crit_exit(); 933 continue; 934 } 935 windex = mbp->msg_bufx; 936 crit_exit(); 937 938 /* 939 * Get message buf FIFO indices. rindex is tracking. 940 */ 941 if ((tp = constty) == NULL) { 942 rindex = mbp->msg_bufx; 943 continue; 944 } 945 946 /* 947 * Don't blow up if the message buffer is broken 948 */ 949 if (windex < 0 || windex >= mbp->msg_size) 950 continue; 951 if (rindex < 0 || rindex >= mbp->msg_size) 952 rindex = windex; 953 954 /* 955 * And dump it. If constty gets stuck will give up. 956 */ 957 while (rindex != windex) { 958 if (tputchar((uint8_t)mbp->msg_ptr[rindex], tp) < 0) { 959 constty = NULL; 960 rindex = mbp->msg_bufx; 961 break; 962 } 963 if (++rindex >= mbp->msg_size) 964 rindex = 0; 965 if (tp->t_outq.c_cc >= tp->t_ohiwat) { 966 tsleep(constty_daemon, 0, "blocked", hz / 10); 967 if (tp->t_outq.c_cc >= tp->t_ohiwat) { 968 rindex = windex; 969 break; 970 } 971 } 972 } 973 } 974 } 975 976 static struct kproc_desc constty_kp = { 977 "consttyd", 978 constty_daemon, 979 &constty_td 980 }; 981 SYSINIT(bufdaemon, SI_SUB_KTHREAD_UPDATE, SI_ORDER_ANY, 982 kproc_start, &constty_kp) 983 984 /* 985 * Put character in log buffer with a particular priority. 986 * 987 * MPSAFE 988 */ 989 static void 990 msglogchar(int c, int pri) 991 { 992 static int lastpri = -1; 993 static int dangling; 994 char nbuf[MAXNBUF]; 995 char *p; 996 997 if (!msgbufmapped) 998 return; 999 if (c == '\0' || c == '\r') 1000 return; 1001 if (pri != -1 && pri != lastpri) { 1002 if (dangling) { 1003 msgaddchar('\n', NULL); 1004 dangling = 0; 1005 } 1006 msgaddchar('<', NULL); 1007 for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;) 1008 msgaddchar(*p--, NULL); 1009 msgaddchar('>', NULL); 1010 lastpri = pri; 1011 } 1012 msgaddchar(c, NULL); 1013 if (c == '\n') { 1014 dangling = 0; 1015 lastpri = -1; 1016 } else { 1017 dangling = 1; 1018 } 1019 } 1020 1021 /* 1022 * Put char in log buffer. Make sure nothing blows up beyond repair if 1023 * we have an MP race. 1024 * 1025 * MPSAFE. 1026 */ 1027 static void 1028 msgaddchar(int c, void *dummy) 1029 { 1030 struct msgbuf *mbp; 1031 int rindex; 1032 int windex; 1033 1034 if (!msgbufmapped) 1035 return; 1036 mbp = msgbufp; 1037 windex = mbp->msg_bufx; 1038 mbp->msg_ptr[windex] = c; 1039 if (++windex >= mbp->msg_size) 1040 windex = 0; 1041 rindex = mbp->msg_bufr; 1042 if (windex == rindex) { 1043 rindex += 32; 1044 if (rindex >= mbp->msg_size) 1045 rindex -= mbp->msg_size; 1046 mbp->msg_bufr = rindex; 1047 } 1048 mbp->msg_bufx = windex; 1049 } 1050 1051 static void 1052 msgbufcopy(struct msgbuf *oldp) 1053 { 1054 int pos; 1055 1056 pos = oldp->msg_bufr; 1057 while (pos != oldp->msg_bufx) { 1058 msglogchar(oldp->msg_ptr[pos], -1); 1059 if (++pos >= oldp->msg_size) 1060 pos = 0; 1061 } 1062 } 1063 1064 void 1065 msgbufinit(void *ptr, size_t size) 1066 { 1067 char *cp; 1068 static struct msgbuf *oldp = NULL; 1069 1070 size -= sizeof(*msgbufp); 1071 cp = (char *)ptr; 1072 msgbufp = (struct msgbuf *) (cp + size); 1073 if (msgbufp->msg_magic != MSG_MAGIC || msgbufp->msg_size != size || 1074 msgbufp->msg_bufx >= size || msgbufp->msg_bufr >= size) { 1075 bzero(cp, size); 1076 bzero(msgbufp, sizeof(*msgbufp)); 1077 msgbufp->msg_magic = MSG_MAGIC; 1078 msgbufp->msg_size = (char *)msgbufp - cp; 1079 } 1080 msgbufp->msg_ptr = cp; 1081 if (msgbufmapped && oldp != msgbufp) 1082 msgbufcopy(oldp); 1083 msgbufmapped = 1; 1084 oldp = msgbufp; 1085 } 1086 1087 /* Sysctls for accessing/clearing the msgbuf */ 1088 1089 static int 1090 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS) 1091 { 1092 struct ucred *cred; 1093 int error; 1094 1095 /* 1096 * Only wheel or root can access the message log. 1097 */ 1098 if (unprivileged_read_msgbuf == 0) { 1099 KKASSERT(req->td->td_proc); 1100 cred = req->td->td_proc->p_ucred; 1101 1102 if ((cred->cr_prison || groupmember(0, cred) == 0) && 1103 priv_check(req->td, PRIV_ROOT) != 0 1104 ) { 1105 return (EPERM); 1106 } 1107 } 1108 1109 /* 1110 * Unwind the buffer, so that it's linear (possibly starting with 1111 * some initial nulls). 1112 */ 1113 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr + msgbufp->msg_bufx, 1114 msgbufp->msg_size - msgbufp->msg_bufx, req); 1115 if (error) 1116 return (error); 1117 if (msgbufp->msg_bufx > 0) { 1118 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr, 1119 msgbufp->msg_bufx, req); 1120 } 1121 return (error); 1122 } 1123 1124 SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD, 1125 0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer"); 1126 1127 static int msgbuf_clear; 1128 1129 static int 1130 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS) 1131 { 1132 int error; 1133 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req); 1134 if (!error && req->newptr) { 1135 /* Clear the buffer and reset write pointer */ 1136 bzero(msgbufp->msg_ptr, msgbufp->msg_size); 1137 msgbufp->msg_bufr = msgbufp->msg_bufx = 0; 1138 msgbuf_clear = 0; 1139 } 1140 return (error); 1141 } 1142 1143 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear, 1144 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clear, 0, 1145 sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer"); 1146 1147 #ifdef DDB 1148 1149 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf) 1150 { 1151 int i, j; 1152 1153 if (!msgbufmapped) { 1154 db_printf("msgbuf not mapped yet\n"); 1155 return; 1156 } 1157 db_printf("msgbufp = %p\n", msgbufp); 1158 db_printf("magic = %x, size = %d, r= %d, w = %d, ptr = %p\n", 1159 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_bufr, 1160 msgbufp->msg_bufx, msgbufp->msg_ptr); 1161 for (i = 0; i < msgbufp->msg_size; i++) { 1162 j = (i + msgbufp->msg_bufr) % msgbufp->msg_size; 1163 db_printf("%c", msgbufp->msg_ptr[j]); 1164 } 1165 db_printf("\n"); 1166 } 1167 1168 #endif /* DDB */ 1169 1170 1171 void 1172 hexdump(const void *ptr, int length, const char *hdr, int flags) 1173 { 1174 int i, j, k; 1175 int cols; 1176 const unsigned char *cp; 1177 char delim; 1178 1179 if ((flags & HD_DELIM_MASK) != 0) 1180 delim = (flags & HD_DELIM_MASK) >> 8; 1181 else 1182 delim = ' '; 1183 1184 if ((flags & HD_COLUMN_MASK) != 0) 1185 cols = flags & HD_COLUMN_MASK; 1186 else 1187 cols = 16; 1188 1189 cp = ptr; 1190 for (i = 0; i < length; i+= cols) { 1191 if (hdr != NULL) 1192 kprintf("%s", hdr); 1193 1194 if ((flags & HD_OMIT_COUNT) == 0) 1195 kprintf("%04x ", i); 1196 1197 if ((flags & HD_OMIT_HEX) == 0) { 1198 for (j = 0; j < cols; j++) { 1199 k = i + j; 1200 if (k < length) 1201 kprintf("%c%02x", delim, cp[k]); 1202 else 1203 kprintf(" "); 1204 } 1205 } 1206 1207 if ((flags & HD_OMIT_CHARS) == 0) { 1208 kprintf(" |"); 1209 for (j = 0; j < cols; j++) { 1210 k = i + j; 1211 if (k >= length) 1212 kprintf(" "); 1213 else if (cp[k] >= ' ' && cp[k] <= '~') 1214 kprintf("%c", cp[k]); 1215 else 1216 kprintf("."); 1217 } 1218 kprintf("|"); 1219 } 1220 kprintf("\n"); 1221 } 1222 } 1223