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 * $DragonFly: src/sys/kern/subr_prf.c,v 1.8 2004/09/13 16:22:36 dillon Exp $ 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/msgbuf.h> 47 #include <sys/malloc.h> 48 #include <sys/proc.h> 49 #include <sys/tty.h> 50 #include <sys/tprintf.h> 51 #include <sys/syslog.h> 52 #include <sys/cons.h> 53 #include <sys/uio.h> 54 #include <sys/sysctl.h> 55 #include <sys/lock.h> 56 57 /* 58 * Note that stdarg.h and the ANSI style va_start macro is used for both 59 * ANSI and traditional C compilers. We use the __ machine version to stay 60 * within the kernel header file set. 61 */ 62 #include <machine/stdarg.h> 63 64 #define TOCONS 0x01 65 #define TOTTY 0x02 66 #define TOLOG 0x04 67 68 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */ 69 #define MAXNBUF (sizeof(quad_t) * NBBY + 1) 70 71 struct putchar_arg { 72 int flags; 73 int pri; 74 struct tty *tty; 75 }; 76 77 struct snprintf_arg { 78 char *str; 79 size_t remain; 80 }; 81 82 extern int log_open; 83 84 struct tty *constty; /* pointer to console "window" tty */ 85 86 static void (*v_putc)(int) = cnputc; /* routine to putc on virtual console */ 87 static void msglogchar(int c, int pri); 88 static void msgaddchar(int c, void *dummy); 89 static void putchar (int ch, void *arg); 90 static char *ksprintn (char *nbuf, u_long num, int base, int *len); 91 static char *ksprintqn (char *nbuf, u_quad_t num, int base, int *len); 92 static void snprintf_func (int ch, void *arg); 93 94 static int consintr = 1; /* Ok to handle console interrupts? */ 95 static int msgbufmapped; /* Set when safe to use msgbuf */ 96 int msgbuftrigger; 97 98 static int log_console_output = 1; 99 TUNABLE_INT("kern.log_console_output", &log_console_output); 100 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RW, 101 &log_console_output, 0, ""); 102 103 /* 104 * Warn that a system table is full. 105 */ 106 void 107 tablefull(const char *tab) 108 { 109 110 log(LOG_ERR, "%s: table is full\n", tab); 111 } 112 113 /* 114 * Uprintf prints to the controlling terminal for the current process. 115 * It may block if the tty queue is overfull. No message is printed if 116 * the queue does not clear in a reasonable time. 117 */ 118 int 119 uprintf(const char *fmt, ...) 120 { 121 struct proc *p = curproc; 122 __va_list ap; 123 struct putchar_arg pca; 124 int retval = 0; 125 126 if (p && p->p_flag & P_CONTROLT && 127 p->p_session->s_ttyvp) { 128 __va_start(ap, fmt); 129 pca.tty = p->p_session->s_ttyp; 130 pca.flags = TOTTY; 131 132 retval = kvprintf(fmt, putchar, &pca, 10, ap); 133 __va_end(ap); 134 } 135 return retval; 136 } 137 138 tpr_t 139 tprintf_open(struct proc *p) 140 { 141 142 if ((p->p_flag & P_CONTROLT) && p->p_session->s_ttyvp) { 143 sess_hold(p->p_session); 144 return ((tpr_t) p->p_session); 145 } 146 return ((tpr_t) NULL); 147 } 148 149 void 150 tprintf_close(tpr_t sess) 151 { 152 if (sess) 153 sess_rele((struct session *) sess); 154 } 155 156 /* 157 * tprintf prints on the controlling terminal associated 158 * with the given session. 159 */ 160 int 161 tprintf(tpr_t tpr, const char *fmt, ...) 162 { 163 struct session *sess = (struct session *)tpr; 164 struct tty *tp = NULL; 165 int flags = TOLOG; 166 __va_list ap; 167 struct putchar_arg pca; 168 int retval; 169 170 if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) { 171 flags |= TOTTY; 172 tp = sess->s_ttyp; 173 } 174 __va_start(ap, fmt); 175 pca.tty = tp; 176 pca.flags = flags; 177 pca.pri = LOG_INFO; 178 retval = kvprintf(fmt, putchar, &pca, 10, ap); 179 __va_end(ap); 180 msgbuftrigger = 1; 181 return retval; 182 } 183 184 /* 185 * Ttyprintf displays a message on a tty; it should be used only by 186 * the tty driver, or anything that knows the underlying tty will not 187 * be revoke(2)'d away. Other callers should use tprintf. 188 */ 189 int 190 ttyprintf(struct tty *tp, const char *fmt, ...) 191 { 192 __va_list ap; 193 struct putchar_arg pca; 194 int retval; 195 196 __va_start(ap, fmt); 197 pca.tty = tp; 198 pca.flags = TOTTY; 199 retval = kvprintf(fmt, putchar, &pca, 10, ap); 200 __va_end(ap); 201 return retval; 202 } 203 204 /* 205 * Log writes to the log buffer, and guarantees not to sleep (so can be 206 * called by interrupt routines). If there is no process reading the 207 * log yet, it writes to the console also. 208 */ 209 int 210 log(int level, const char *fmt, ...) 211 { 212 __va_list ap; 213 int retval; 214 struct putchar_arg pca; 215 216 pca.tty = NULL; 217 pca.pri = level; 218 pca.flags = log_open ? TOLOG : TOCONS; 219 220 __va_start(ap, fmt); 221 retval = kvprintf(fmt, putchar, &pca, 10, ap); 222 __va_end(ap); 223 224 msgbuftrigger = 1; 225 return (retval); 226 } 227 228 int 229 addlog(const char *fmt, ...) 230 { 231 __va_list ap; 232 int retval; 233 struct putchar_arg pca; 234 235 pca.tty = NULL; 236 pca.pri = -1; 237 pca.flags = log_open ? TOLOG : TOCONS; 238 239 __va_start(ap, fmt); 240 retval = kvprintf(fmt, putchar, &pca, 10, ap); 241 __va_end(ap); 242 243 msgbuftrigger = 1; 244 return (retval); 245 } 246 247 #define CONSCHUNK 128 248 249 void 250 log_console(struct uio *uio) 251 { 252 int c, i, error, iovlen, nl; 253 struct uio muio; 254 struct iovec *miov = NULL; 255 char *consbuffer; 256 int pri; 257 258 if (!log_console_output) 259 return; 260 261 pri = LOG_INFO | LOG_CONSOLE; 262 muio = *uio; 263 iovlen = uio->uio_iovcnt * sizeof (struct iovec); 264 MALLOC(miov, struct iovec *, iovlen, M_TEMP, M_WAITOK); 265 MALLOC(consbuffer, char *, CONSCHUNK, M_TEMP, M_WAITOK); 266 bcopy((caddr_t)muio.uio_iov, (caddr_t)miov, iovlen); 267 muio.uio_iov = miov; 268 uio = &muio; 269 270 nl = 0; 271 while (uio->uio_resid > 0) { 272 c = imin(uio->uio_resid, CONSCHUNK); 273 error = uiomove(consbuffer, c, uio); 274 if (error != 0) 275 return; 276 for (i = 0; i < c; i++) { 277 msglogchar(consbuffer[i], pri); 278 if (consbuffer[i] == '\n') 279 nl = 1; 280 else 281 nl = 0; 282 } 283 } 284 if (!nl) 285 msglogchar('\n', pri); 286 msgbuftrigger = 1; 287 FREE(miov, M_TEMP); 288 FREE(consbuffer, M_TEMP); 289 return; 290 } 291 292 int 293 printf(const char *fmt, ...) 294 { 295 __va_list ap; 296 int savintr; 297 struct putchar_arg pca; 298 int retval; 299 300 savintr = consintr; /* disable interrupts */ 301 consintr = 0; 302 __va_start(ap, fmt); 303 pca.tty = NULL; 304 pca.flags = TOCONS | TOLOG; 305 pca.pri = -1; 306 cons_lock(); 307 retval = kvprintf(fmt, putchar, &pca, 10, ap); 308 cons_unlock(); 309 __va_end(ap); 310 if (!panicstr) 311 msgbuftrigger = 1; 312 consintr = savintr; /* reenable interrupts */ 313 return retval; 314 } 315 316 int 317 vprintf(const char *fmt, __va_list ap) 318 { 319 int savintr; 320 struct putchar_arg pca; 321 int retval; 322 323 savintr = consintr; /* disable interrupts */ 324 consintr = 0; 325 pca.tty = NULL; 326 pca.flags = TOCONS | TOLOG; 327 pca.pri = -1; 328 cons_lock(); 329 retval = kvprintf(fmt, putchar, &pca, 10, ap); 330 cons_unlock(); 331 if (!panicstr) 332 msgbuftrigger = 1; 333 consintr = savintr; /* reenable interrupts */ 334 return retval; 335 } 336 337 /* 338 * Print a character on console or users terminal. If destination is 339 * the console then the last bunch of characters are saved in msgbuf for 340 * inspection later. 341 */ 342 static void 343 putchar(int c, void *arg) 344 { 345 struct putchar_arg *ap = (struct putchar_arg*) arg; 346 int flags = ap->flags; 347 struct tty *tp = ap->tty; 348 if (panicstr) 349 constty = NULL; 350 if ((flags & TOCONS) && tp == NULL && constty) { 351 tp = constty; 352 flags |= TOTTY; 353 } 354 if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 && 355 (flags & TOCONS) && tp == constty) 356 constty = NULL; 357 if ((flags & TOLOG)) 358 msglogchar(c, ap->pri); 359 if ((flags & TOCONS) && constty == NULL && c != '\0') 360 (*v_putc)(c); 361 } 362 363 /* 364 * Scaled down version of sprintf(3). 365 */ 366 int 367 sprintf(char *buf, const char *cfmt, ...) 368 { 369 int retval; 370 __va_list ap; 371 372 __va_start(ap, cfmt); 373 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap); 374 buf[retval] = '\0'; 375 __va_end(ap); 376 return retval; 377 } 378 379 /* 380 * Scaled down version of vsprintf(3). 381 */ 382 int 383 vsprintf(char *buf, const char *cfmt, __va_list ap) 384 { 385 int retval; 386 387 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap); 388 buf[retval] = '\0'; 389 return retval; 390 } 391 392 /* 393 * Scaled down version of snprintf(3). 394 */ 395 int 396 snprintf(char *str, size_t size, const char *format, ...) 397 { 398 int retval; 399 __va_list ap; 400 401 __va_start(ap, format); 402 retval = vsnprintf(str, size, format, ap); 403 __va_end(ap); 404 return(retval); 405 } 406 407 /* 408 * Scaled down version of vsnprintf(3). 409 */ 410 int 411 vsnprintf(char *str, size_t size, const char *format, __va_list ap) 412 { 413 struct snprintf_arg info; 414 int retval; 415 416 info.str = str; 417 info.remain = size; 418 retval = kvprintf(format, snprintf_func, &info, 10, ap); 419 if (info.remain >= 1) 420 *info.str++ = '\0'; 421 return retval; 422 } 423 424 static void 425 snprintf_func(int ch, void *arg) 426 { 427 struct snprintf_arg *const info = arg; 428 429 if (info->remain >= 2) { 430 *info->str++ = ch; 431 info->remain--; 432 } 433 } 434 435 /* 436 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse 437 * order; return an optional length and a pointer to the last character 438 * written in the buffer (i.e., the first character of the string). 439 * The buffer pointed to by `nbuf' must have length >= MAXNBUF. 440 */ 441 static char * 442 ksprintn(nbuf, ul, base, lenp) 443 char *nbuf; 444 u_long ul; 445 int base, *lenp; 446 { 447 char *p; 448 449 p = nbuf; 450 *p = '\0'; 451 do { 452 *++p = hex2ascii(ul % base); 453 } while (ul /= base); 454 if (lenp) 455 *lenp = p - nbuf; 456 return (p); 457 } 458 /* ksprintn, but for a quad_t. */ 459 static char * 460 ksprintqn(nbuf, uq, base, lenp) 461 char *nbuf; 462 u_quad_t uq; 463 int base, *lenp; 464 { 465 char *p; 466 467 p = nbuf; 468 *p = '\0'; 469 do { 470 *++p = hex2ascii(uq % base); 471 } while (uq /= base); 472 if (lenp) 473 *lenp = p - nbuf; 474 return (p); 475 } 476 477 /* 478 * Scaled down version of printf(3). 479 * 480 * Two additional formats: 481 * 482 * The format %b is supported to decode error registers. 483 * Its usage is: 484 * 485 * printf("reg=%b\n", regval, "<base><arg>*"); 486 * 487 * where <base> is the output base expressed as a control character, e.g. 488 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters, 489 * the first of which gives the bit number to be inspected (origin 1), and 490 * the next characters (up to a control character, i.e. a character <= 32), 491 * give the name of the register. Thus: 492 * 493 * kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n"); 494 * 495 * would produce output: 496 * 497 * reg=3<BITTWO,BITONE> 498 * 499 * XXX: %D -- Hexdump, takes pointer and separator string: 500 * ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX 501 * ("%*D", len, ptr, " " -> XX XX XX XX ... 502 */ 503 int 504 kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, __va_list ap) 505 { 506 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; } 507 char nbuf[MAXNBUF]; 508 char *p, *q, *d; 509 u_char *up; 510 int ch, n; 511 u_long ul; 512 u_quad_t uq; 513 int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot; 514 int dwidth; 515 char padc; 516 int retval = 0; 517 518 ul = 0; 519 uq = 0; 520 if (!func) 521 d = (char *) arg; 522 else 523 d = NULL; 524 525 if (fmt == NULL) 526 fmt = "(fmt null)\n"; 527 528 if (radix < 2 || radix > 36) 529 radix = 10; 530 531 for (;;) { 532 padc = ' '; 533 width = 0; 534 while ((ch = (u_char)*fmt++) != '%') { 535 if (ch == '\0') 536 return retval; 537 PCHAR(ch); 538 } 539 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0; 540 sign = 0; dot = 0; dwidth = 0; 541 reswitch: switch (ch = (u_char)*fmt++) { 542 case '.': 543 dot = 1; 544 goto reswitch; 545 case '#': 546 sharpflag = 1; 547 goto reswitch; 548 case '+': 549 sign = 1; 550 goto reswitch; 551 case '-': 552 ladjust = 1; 553 goto reswitch; 554 case '%': 555 PCHAR(ch); 556 break; 557 case '*': 558 if (!dot) { 559 width = __va_arg(ap, int); 560 if (width < 0) { 561 ladjust = !ladjust; 562 width = -width; 563 } 564 } else { 565 dwidth = __va_arg(ap, int); 566 } 567 goto reswitch; 568 case '0': 569 if (!dot) { 570 padc = '0'; 571 goto reswitch; 572 } 573 case '1': case '2': case '3': case '4': 574 case '5': case '6': case '7': case '8': case '9': 575 for (n = 0;; ++fmt) { 576 n = n * 10 + ch - '0'; 577 ch = *fmt; 578 if (ch < '0' || ch > '9') 579 break; 580 } 581 if (dot) 582 dwidth = n; 583 else 584 width = n; 585 goto reswitch; 586 case 'b': 587 ul = __va_arg(ap, int); 588 p = __va_arg(ap, char *); 589 for (q = ksprintn(nbuf, ul, *p++, NULL); *q;) 590 PCHAR(*q--); 591 592 if (!ul) 593 break; 594 595 for (tmp = 0; *p;) { 596 n = *p++; 597 if (ul & (1 << (n - 1))) { 598 PCHAR(tmp ? ',' : '<'); 599 for (; (n = *p) > ' '; ++p) 600 PCHAR(n); 601 tmp = 1; 602 } else 603 for (; *p > ' '; ++p) 604 continue; 605 } 606 if (tmp) 607 PCHAR('>'); 608 break; 609 case 'c': 610 PCHAR(__va_arg(ap, int)); 611 break; 612 case 'D': 613 up = __va_arg(ap, u_char *); 614 p = __va_arg(ap, char *); 615 if (!width) 616 width = 16; 617 while(width--) { 618 PCHAR(hex2ascii(*up >> 4)); 619 PCHAR(hex2ascii(*up & 0x0f)); 620 up++; 621 if (width) 622 for (q=p;*q;q++) 623 PCHAR(*q); 624 } 625 break; 626 case 'd': 627 if (qflag) 628 uq = __va_arg(ap, quad_t); 629 else if (lflag) 630 ul = __va_arg(ap, long); 631 else 632 ul = __va_arg(ap, int); 633 sign = 1; 634 base = 10; 635 goto number; 636 case 'l': 637 if (lflag) { 638 lflag = 0; 639 qflag = 1; 640 } else 641 lflag = 1; 642 goto reswitch; 643 case 'o': 644 if (qflag) 645 uq = __va_arg(ap, u_quad_t); 646 else if (lflag) 647 ul = __va_arg(ap, u_long); 648 else 649 ul = __va_arg(ap, u_int); 650 base = 8; 651 goto nosign; 652 case 'p': 653 ul = (uintptr_t)__va_arg(ap, void *); 654 base = 16; 655 sharpflag = (width == 0); 656 goto nosign; 657 case 'q': 658 qflag = 1; 659 goto reswitch; 660 case 'n': 661 case 'r': 662 if (qflag) 663 uq = __va_arg(ap, u_quad_t); 664 else if (lflag) 665 ul = __va_arg(ap, u_long); 666 else 667 ul = sign ? 668 (u_long)__va_arg(ap, int) : __va_arg(ap, u_int); 669 base = radix; 670 goto number; 671 case 's': 672 p = __va_arg(ap, char *); 673 if (p == NULL) 674 p = "(null)"; 675 if (!dot) 676 n = strlen (p); 677 else 678 for (n = 0; n < dwidth && p[n]; n++) 679 continue; 680 681 width -= n; 682 683 if (!ladjust && width > 0) 684 while (width--) 685 PCHAR(padc); 686 while (n--) 687 PCHAR(*p++); 688 if (ladjust && width > 0) 689 while (width--) 690 PCHAR(padc); 691 break; 692 case 'u': 693 if (qflag) 694 uq = __va_arg(ap, u_quad_t); 695 else if (lflag) 696 ul = __va_arg(ap, u_long); 697 else 698 ul = __va_arg(ap, u_int); 699 base = 10; 700 goto nosign; 701 case 'x': 702 case 'X': 703 if (qflag) 704 uq = __va_arg(ap, u_quad_t); 705 else if (lflag) 706 ul = __va_arg(ap, u_long); 707 else 708 ul = __va_arg(ap, u_int); 709 base = 16; 710 goto nosign; 711 case 'z': 712 if (qflag) 713 uq = __va_arg(ap, u_quad_t); 714 else if (lflag) 715 ul = __va_arg(ap, u_long); 716 else 717 ul = sign ? 718 (u_long)__va_arg(ap, int) : __va_arg(ap, u_int); 719 base = 16; 720 goto number; 721 nosign: sign = 0; 722 number: 723 if (qflag) { 724 if (sign && (quad_t)uq < 0) { 725 neg = 1; 726 uq = -(quad_t)uq; 727 } 728 p = ksprintqn(nbuf, uq, base, &tmp); 729 } else { 730 if (sign && (long)ul < 0) { 731 neg = 1; 732 ul = -(long)ul; 733 } 734 p = ksprintn(nbuf, ul, base, &tmp); 735 } 736 if (sharpflag && (qflag ? uq != 0 : ul != 0)) { 737 if (base == 8) 738 tmp++; 739 else if (base == 16) 740 tmp += 2; 741 } 742 if (neg) 743 tmp++; 744 745 if (!ladjust && width && (width -= tmp) > 0) 746 while (width--) 747 PCHAR(padc); 748 if (neg) 749 PCHAR('-'); 750 if (sharpflag && (qflag ? uq != 0 : ul != 0)) { 751 if (base == 8) { 752 PCHAR('0'); 753 } else if (base == 16) { 754 PCHAR('0'); 755 PCHAR('x'); 756 } 757 } 758 759 while (*p) 760 PCHAR(*p--); 761 762 if (ladjust && width && (width -= tmp) > 0) 763 while (width--) 764 PCHAR(padc); 765 766 break; 767 default: 768 PCHAR('%'); 769 if (lflag) 770 PCHAR('l'); 771 PCHAR(ch); 772 break; 773 } 774 } 775 #undef PCHAR 776 } 777 778 /* 779 * Put character in log buffer with a particular priority. 780 */ 781 static void 782 msglogchar(int c, int pri) 783 { 784 static int lastpri = -1; 785 static int dangling; 786 char nbuf[MAXNBUF]; 787 char *p; 788 789 if (!msgbufmapped) 790 return; 791 if (c == '\0' || c == '\r') 792 return; 793 if (pri != -1 && pri != lastpri) { 794 if (dangling) { 795 msgaddchar('\n', NULL); 796 dangling = 0; 797 } 798 msgaddchar('<', NULL); 799 for (p = ksprintn(nbuf, (u_long)pri, 10, NULL); *p;) 800 msgaddchar(*p--, NULL); 801 msgaddchar('>', NULL); 802 lastpri = pri; 803 } 804 msgaddchar(c, NULL); 805 if (c == '\n') { 806 dangling = 0; 807 lastpri = -1; 808 } else { 809 dangling = 1; 810 } 811 } 812 813 /* 814 * Put char in log buffer 815 */ 816 static void 817 msgaddchar(int c, void *dummy) 818 { 819 struct msgbuf *mbp; 820 821 if (!msgbufmapped) 822 return; 823 mbp = msgbufp; 824 mbp->msg_ptr[mbp->msg_bufx++] = c; 825 if (mbp->msg_bufx >= mbp->msg_size) 826 mbp->msg_bufx = 0; 827 /* If the buffer is full, keep the most recent data. */ 828 if (mbp->msg_bufr == mbp->msg_bufx) { 829 if (++mbp->msg_bufr >= mbp->msg_size) 830 mbp->msg_bufr = 0; 831 } 832 } 833 834 static void 835 msgbufcopy(struct msgbuf *oldp) 836 { 837 int pos; 838 839 pos = oldp->msg_bufr; 840 while (pos != oldp->msg_bufx) { 841 msglogchar(oldp->msg_ptr[pos], -1); 842 if (++pos >= oldp->msg_size) 843 pos = 0; 844 } 845 } 846 847 void 848 msgbufinit(void *ptr, size_t size) 849 { 850 char *cp; 851 static struct msgbuf *oldp = NULL; 852 853 size -= sizeof(*msgbufp); 854 cp = (char *)ptr; 855 msgbufp = (struct msgbuf *) (cp + size); 856 if (msgbufp->msg_magic != MSG_MAGIC || msgbufp->msg_size != size || 857 msgbufp->msg_bufx >= size || msgbufp->msg_bufr >= size) { 858 bzero(cp, size); 859 bzero(msgbufp, sizeof(*msgbufp)); 860 msgbufp->msg_magic = MSG_MAGIC; 861 msgbufp->msg_size = (char *)msgbufp - cp; 862 } 863 msgbufp->msg_ptr = cp; 864 if (msgbufmapped && oldp != msgbufp) 865 msgbufcopy(oldp); 866 msgbufmapped = 1; 867 oldp = msgbufp; 868 } 869 870 /* Sysctls for accessing/clearing the msgbuf */ 871 static int 872 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS) 873 { 874 int error; 875 876 /* 877 * Unwind the buffer, so that it's linear (possibly starting with 878 * some initial nulls). 879 */ 880 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr + msgbufp->msg_bufx, 881 msgbufp->msg_size - msgbufp->msg_bufx, req); 882 if (error) 883 return (error); 884 if (msgbufp->msg_bufx > 0) { 885 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr, 886 msgbufp->msg_bufx, req); 887 } 888 return (error); 889 } 890 891 SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD, 892 0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer"); 893 894 static int msgbuf_clear; 895 896 static int 897 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS) 898 { 899 int error; 900 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req); 901 if (!error && req->newptr) { 902 /* Clear the buffer and reset write pointer */ 903 bzero(msgbufp->msg_ptr, msgbufp->msg_size); 904 msgbufp->msg_bufr = msgbufp->msg_bufx = 0; 905 msgbuf_clear = 0; 906 } 907 return (error); 908 } 909 910 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear, 911 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clear, 0, 912 sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer"); 913 914 #include "opt_ddb.h" 915 #ifdef DDB 916 #include <ddb/ddb.h> 917 918 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf) 919 { 920 int i, j; 921 922 if (!msgbufmapped) { 923 db_printf("msgbuf not mapped yet\n"); 924 return; 925 } 926 db_printf("msgbufp = %p\n", msgbufp); 927 db_printf("magic = %x, size = %d, r= %d, w = %d, ptr = %p\n", 928 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_bufr, 929 msgbufp->msg_bufx, msgbufp->msg_ptr); 930 for (i = 0; i < msgbufp->msg_size; i++) { 931 j = (i + msgbufp->msg_bufr) % msgbufp->msg_size; 932 db_printf("%c", msgbufp->msg_ptr[j]); 933 } 934 db_printf("\n"); 935 } 936 937 #endif /* DDB */ 938