1 /* $OpenBSD: subr_prf.c,v 1.87 2016/05/17 23:43:47 bluhm Exp $ */ 2 /* $NetBSD: subr_prf.c,v 1.45 1997/10/24 18:14:25 chuck Exp $ */ 3 4 /*- 5 * Copyright (c) 1986, 1988, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * (c) UNIX System Laboratories, Inc. 8 * All or some portions of this file are derived from material licensed 9 * to the University of California by American Telephone and Telegraph 10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 11 * the permission of UNIX System Laboratories, Inc. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)subr_prf.c 8.3 (Berkeley) 1/21/94 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/conf.h> 43 #include <sys/reboot.h> 44 #include <sys/msgbuf.h> 45 #include <sys/proc.h> 46 #include <sys/ioctl.h> 47 #include <sys/vnode.h> 48 #include <sys/file.h> 49 #include <sys/tty.h> 50 #include <sys/tprintf.h> 51 #include <sys/syslog.h> 52 #include <sys/malloc.h> 53 #include <sys/pool.h> 54 #include <sys/mutex.h> 55 56 #include <dev/cons.h> 57 58 /* 59 * note that stdarg.h and the ansi style va_start macro is used for both 60 * ansi and traditional c compilers. 61 */ 62 #include <sys/stdarg.h> 63 64 #ifdef KGDB 65 #include <sys/kgdb.h> 66 #endif 67 #ifdef DDB 68 #include <ddb/db_output.h> /* db_printf, db_putchar prototypes */ 69 #include <ddb/db_var.h> /* db_log, db_radix */ 70 #endif 71 72 73 /* 74 * defines 75 */ 76 77 /* flags for kprintf */ 78 #define TOCONS 0x01 /* to the console */ 79 #define TOTTY 0x02 /* to the process' tty */ 80 #define TOLOG 0x04 /* to the kernel message buffer */ 81 #define TOBUFONLY 0x08 /* to the buffer (only) [for snprintf] */ 82 #define TODDB 0x10 /* to ddb console */ 83 #define TOCOUNT 0x20 /* act like [v]snprintf */ 84 85 /* max size buffer kprintf needs to print quad_t [size in base 8 + \0] */ 86 #define KPRINTF_BUFSIZE (sizeof(quad_t) * NBBY / 3 + 2) 87 88 89 /* 90 * local prototypes 91 */ 92 93 int kprintf(const char *, int, void *, char *, va_list); 94 void kputchar(int, int, struct tty *); 95 96 struct mutex kprintf_mutex = MUTEX_INITIALIZER(IPL_HIGH); 97 98 /* 99 * globals 100 */ 101 102 extern int log_open; /* subr_log: is /dev/klog open? */ 103 const char *panicstr; /* arg to first call to panic (used as a flag 104 to indicate that panic has already been called). */ 105 #ifdef DDB 106 /* 107 * Enter ddb on panic. 108 */ 109 int db_panic = 1; 110 111 /* 112 * db_console controls if we can be able to enter ddb by a special key 113 * combination (machine dependent). 114 * If DDB_SAFE_CONSOLE is defined in the kernel configuration it allows 115 * to break into console during boot. It's _really_ useful when debugging 116 * some things in the kernel that can cause init(8) to crash. 117 */ 118 #ifdef DDB_SAFE_CONSOLE 119 int db_console = 1; 120 #else 121 int db_console = 0; 122 #endif 123 124 /* 125 * flag to indicate if we are currently in ddb (on some processor) 126 */ 127 int db_is_active; 128 #endif 129 130 /* 131 * panic on spl assertion failure? 132 */ 133 int splassert_ctl = 1; 134 135 /* 136 * v_putc: routine to putc on virtual console 137 * 138 * the v_putc pointer can be used to redirect the console cnputc elsewhere 139 * [e.g. to a "virtual console"]. 140 */ 141 142 void (*v_putc)(int) = cnputc; /* start with cnputc (normal cons) */ 143 144 145 /* 146 * functions 147 */ 148 149 /* 150 * Partial support (the failure case) of the assertion facility 151 * commonly found in userland. 152 */ 153 void 154 __assert(const char *t, const char *f, int l, const char *e) 155 { 156 157 panic(__KASSERTSTR, t, e, f, l); 158 } 159 160 /* 161 * tablefull: warn that a system table is full 162 */ 163 164 void 165 tablefull(const char *tab) 166 { 167 log(LOG_ERR, "%s: table is full\n", tab); 168 } 169 170 /* 171 * panic: handle an unresolvable fatal error 172 * 173 * prints "panic: <message>" and reboots. if called twice (i.e. recursive 174 * call) we avoid trying to sync the disk and just reboot (to avoid 175 * recursive panics). 176 */ 177 178 void 179 panic(const char *fmt, ...) 180 { 181 static char panicbuf[512]; 182 int bootopt; 183 va_list ap; 184 185 /* do not trigger assertions, we know that we are inconsistent */ 186 splassert_ctl = 0; 187 188 bootopt = RB_AUTOBOOT | RB_DUMP; 189 va_start(ap, fmt); 190 if (panicstr) 191 bootopt |= RB_NOSYNC; 192 else { 193 vsnprintf(panicbuf, sizeof panicbuf, fmt, ap); 194 panicstr = panicbuf; 195 } 196 va_end(ap); 197 198 printf("panic: "); 199 va_start(ap, fmt); 200 vprintf(fmt, ap); 201 printf("\n"); 202 va_end(ap); 203 204 #ifdef KGDB 205 kgdb_panic(); 206 #endif 207 #ifdef KADB 208 if (boothowto & RB_KDB) 209 kdbpanic(); 210 #endif 211 #ifdef DDB 212 if (db_panic) 213 Debugger(); 214 else 215 db_stack_dump(); 216 #endif 217 reboot(bootopt); 218 /* NOTREACHED */ 219 } 220 221 /* 222 * We print only the function name. The file name is usually very long and 223 * would eat tons of space in the kernel. 224 */ 225 void 226 splassert_fail(int wantipl, int haveipl, const char *func) 227 { 228 229 printf("splassert: %s: want %d have %d\n", func, wantipl, haveipl); 230 switch (splassert_ctl) { 231 case 1: 232 break; 233 case 2: 234 #ifdef DDB 235 db_stack_dump(); 236 #endif 237 break; 238 case 3: 239 #ifdef DDB 240 db_stack_dump(); 241 Debugger(); 242 #endif 243 break; 244 default: 245 panic("spl assertion failure in %s", func); 246 } 247 } 248 249 /* 250 * kernel logging functions: log, logpri, addlog 251 */ 252 253 /* 254 * log: write to the log buffer 255 * 256 * => will not sleep [so safe to call from interrupt] 257 * => will log to console if /dev/klog isn't open 258 */ 259 260 void 261 log(int level, const char *fmt, ...) 262 { 263 int s; 264 va_list ap; 265 266 s = splhigh(); 267 logpri(level); /* log the level first */ 268 va_start(ap, fmt); 269 kprintf(fmt, TOLOG, NULL, NULL, ap); 270 va_end(ap); 271 splx(s); 272 if (!log_open) { 273 va_start(ap, fmt); 274 kprintf(fmt, TOCONS, NULL, NULL, ap); 275 va_end(ap); 276 } 277 logwakeup(); /* wake up anyone waiting for log msgs */ 278 } 279 280 /* 281 * logpri: log the priority level to the klog 282 */ 283 284 void 285 logpri(int level) 286 { 287 char *p; 288 char snbuf[KPRINTF_BUFSIZE]; 289 290 kputchar('<', TOLOG, NULL); 291 snprintf(snbuf, sizeof snbuf, "%d", level); 292 for (p = snbuf ; *p ; p++) 293 kputchar(*p, TOLOG, NULL); 294 kputchar('>', TOLOG, NULL); 295 } 296 297 /* 298 * addlog: add info to previous log message 299 */ 300 301 int 302 addlog(const char *fmt, ...) 303 { 304 int s; 305 va_list ap; 306 307 s = splhigh(); 308 va_start(ap, fmt); 309 kprintf(fmt, TOLOG, NULL, NULL, ap); 310 va_end(ap); 311 splx(s); 312 if (!log_open) { 313 va_start(ap, fmt); 314 kprintf(fmt, TOCONS, NULL, NULL, ap); 315 va_end(ap); 316 } 317 logwakeup(); 318 return(0); 319 } 320 321 322 /* 323 * kputchar: print a single character on console or user terminal. 324 * 325 * => if console, then the last MSGBUFS chars are saved in msgbuf 326 * for inspection later (e.g. dmesg/syslog) 327 */ 328 void 329 kputchar(int c, int flags, struct tty *tp) 330 { 331 extern int msgbufmapped; 332 int ddb_active = 0; 333 334 #ifdef DDB 335 ddb_active = db_is_active; 336 #endif 337 338 if (panicstr) 339 constty = NULL; 340 341 if ((flags & TOCONS) && tp == NULL && constty && !ddb_active) { 342 tp = constty; 343 flags |= TOTTY; 344 } 345 if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 && 346 (flags & TOCONS) && tp == constty) 347 constty = NULL; 348 if ((flags & TOLOG) && 349 c != '\0' && c != '\r' && c != 0177 && msgbufmapped) 350 msgbuf_putchar(msgbufp, c); 351 if ((flags & TOCONS) && (constty == NULL || ddb_active) && c != '\0') 352 (*v_putc)(c); 353 #ifdef DDB 354 if (flags & TODDB) 355 db_putchar(c); 356 #endif 357 } 358 359 360 /* 361 * uprintf: print to the controlling tty of the current process 362 * 363 * => we may block if the tty queue is full 364 * => no message is printed if the queue doesn't clear in a reasonable 365 * time 366 */ 367 368 void 369 uprintf(const char *fmt, ...) 370 { 371 struct process *pr = curproc->p_p; 372 va_list ap; 373 374 if (pr->ps_flags & PS_CONTROLT && pr->ps_session->s_ttyvp) { 375 va_start(ap, fmt); 376 kprintf(fmt, TOTTY, pr->ps_session->s_ttyp, NULL, ap); 377 va_end(ap); 378 } 379 } 380 381 #if defined(NFSSERVER) || defined(NFSCLIENT) 382 383 /* 384 * tprintf functions: used to send messages to a specific process 385 * 386 * usage: 387 * get a tpr_t handle on a process "p" by using "tprintf_open(p)" 388 * use the handle when calling "tprintf" 389 * when done, do a "tprintf_close" to drop the handle 390 */ 391 392 /* 393 * tprintf_open: get a tprintf handle on a process "p" 394 * XXX change s/proc/process 395 * 396 * => returns NULL if process can't be printed to 397 */ 398 399 tpr_t 400 tprintf_open(struct proc *p) 401 { 402 struct process *pr = p->p_p; 403 404 if (pr->ps_flags & PS_CONTROLT && pr->ps_session->s_ttyvp) { 405 SESSHOLD(pr->ps_session); 406 return ((tpr_t)pr->ps_session); 407 } 408 return ((tpr_t) NULL); 409 } 410 411 /* 412 * tprintf_close: dispose of a tprintf handle obtained with tprintf_open 413 */ 414 415 void 416 tprintf_close(tpr_t sess) 417 { 418 419 if (sess) 420 SESSRELE((struct session *) sess); 421 } 422 423 /* 424 * tprintf: given tprintf handle to a process [obtained with tprintf_open], 425 * send a message to the controlling tty for that process. 426 * 427 * => also sends message to /dev/klog 428 */ 429 void 430 tprintf(tpr_t tpr, const char *fmt, ...) 431 { 432 struct session *sess = (struct session *)tpr; 433 struct tty *tp = NULL; 434 int flags = TOLOG; 435 va_list ap; 436 437 logpri(LOG_INFO); 438 if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) { 439 flags |= TOTTY; 440 tp = sess->s_ttyp; 441 } 442 va_start(ap, fmt); 443 kprintf(fmt, flags, tp, NULL, ap); 444 va_end(ap); 445 logwakeup(); 446 } 447 448 #endif /* NFSSERVER || NFSCLIENT */ 449 450 451 /* 452 * ttyprintf: send a message to a specific tty 453 * 454 * => should be used only by tty driver or anything that knows the 455 * underlying tty will not be revoked(2)'d away. [otherwise, 456 * use tprintf] 457 */ 458 void 459 ttyprintf(struct tty *tp, const char *fmt, ...) 460 { 461 va_list ap; 462 463 va_start(ap, fmt); 464 kprintf(fmt, TOTTY, tp, NULL, ap); 465 va_end(ap); 466 } 467 468 #ifdef DDB 469 470 /* 471 * db_printf: printf for DDB (via db_putchar) 472 */ 473 474 int 475 db_printf(const char *fmt, ...) 476 { 477 va_list ap; 478 int retval; 479 480 va_start(ap, fmt); 481 retval = db_vprintf(fmt, ap); 482 va_end(ap); 483 return(retval); 484 } 485 486 int 487 db_vprintf(const char *fmt, va_list ap) 488 { 489 int flags; 490 491 flags = TODDB; 492 if (db_log) 493 flags |= TOLOG; 494 return (kprintf(fmt, flags, NULL, NULL, ap)); 495 } 496 #endif /* DDB */ 497 498 499 /* 500 * normal kernel printf functions: printf, vprintf, snprintf 501 */ 502 503 /* 504 * printf: print a message to the console and the log 505 */ 506 int 507 printf(const char *fmt, ...) 508 { 509 va_list ap; 510 int retval; 511 512 mtx_enter(&kprintf_mutex); 513 514 va_start(ap, fmt); 515 retval = kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap); 516 va_end(ap); 517 if (!panicstr) 518 logwakeup(); 519 520 mtx_leave(&kprintf_mutex); 521 522 return(retval); 523 } 524 525 /* 526 * vprintf: print a message to the console and the log [already have a 527 * va_list] 528 */ 529 530 int 531 vprintf(const char *fmt, va_list ap) 532 { 533 int retval; 534 535 mtx_enter(&kprintf_mutex); 536 537 retval = kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap); 538 if (!panicstr) 539 logwakeup(); 540 541 mtx_leave(&kprintf_mutex); 542 543 return (retval); 544 } 545 546 /* 547 * snprintf: print a message to a buffer 548 */ 549 int 550 snprintf(char *buf, size_t size, const char *fmt, ...) 551 { 552 int retval; 553 va_list ap; 554 char *p; 555 556 p = buf + size - 1; 557 if (size < 1) 558 p = buf; 559 va_start(ap, fmt); 560 retval = kprintf(fmt, TOBUFONLY | TOCOUNT, &p, buf, ap); 561 va_end(ap); 562 if (size > 0) 563 *(p) = 0; /* null terminate */ 564 return(retval); 565 } 566 567 /* 568 * vsnprintf: print a message to a buffer [already have va_alist] 569 */ 570 int 571 vsnprintf(char *buf, size_t size, const char *fmt, va_list ap) 572 { 573 int retval; 574 char *p; 575 576 p = buf + size - 1; 577 if (size < 1) 578 p = buf; 579 retval = kprintf(fmt, TOBUFONLY | TOCOUNT, &p, buf, ap); 580 if (size > 0) 581 *(p) = 0; /* null terminate */ 582 return(retval); 583 } 584 585 /* 586 * kprintf: scaled down version of printf(3). 587 * 588 * this version based on vfprintf() from libc which was derived from 589 * software contributed to Berkeley by Chris Torek. 590 * 591 * The additional format %b is supported to decode error registers. 592 * Its usage is: 593 * 594 * printf("reg=%b\n", regval, "<base><arg>*"); 595 * 596 * where <base> is the output base expressed as a control character, e.g. 597 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters, 598 * the first of which gives the bit number to be inspected (origin 1), and 599 * the next characters (up to a control character, i.e. a character <= 32), 600 * give the name of the register. Thus: 601 * 602 * kprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n"); 603 * 604 * would produce output: 605 * 606 * reg=3<BITTWO,BITONE> 607 * 608 * To support larger integers (> 32 bits), %b formatting will also accept 609 * control characters in the region 0x80 - 0xff. 0x80 refers to bit 0, 610 * 0x81 refers to bit 1, and so on. The equivalent string to the above is: 611 * 612 * kprintf("reg=%b\n", 3, "\10\201BITTWO\200BITONE\n"); 613 * 614 * and would produce the same output. 615 * 616 * Like the rest of printf, %b can be prefixed to handle various size 617 * modifiers, eg. %b is for "int", %lb is for "long", and %llb supports 618 * "long long". 619 * 620 * This code is large and complicated... 621 */ 622 623 /* 624 * macros for converting digits to letters and vice versa 625 */ 626 #define to_digit(c) ((c) - '0') 627 #define is_digit(c) ((unsigned)to_digit(c) <= 9) 628 #define to_char(n) ((n) + '0') 629 630 /* 631 * flags used during conversion. 632 */ 633 #define ALT 0x001 /* alternate form */ 634 #define HEXPREFIX 0x002 /* add 0x or 0X prefix */ 635 #define LADJUST 0x004 /* left adjustment */ 636 #define LONGDBL 0x008 /* long double; unimplemented */ 637 #define LONGINT 0x010 /* long integer */ 638 #define QUADINT 0x020 /* quad integer */ 639 #define SHORTINT 0x040 /* short integer */ 640 #define ZEROPAD 0x080 /* zero (as opposed to blank) pad */ 641 #define FPT 0x100 /* Floating point number */ 642 #define SIZEINT 0x200 /* (signed) size_t */ 643 644 /* 645 * To extend shorts properly, we need both signed and unsigned 646 * argument extraction methods. 647 */ 648 #define SARG() \ 649 (flags&QUADINT ? va_arg(ap, quad_t) : \ 650 flags&LONGINT ? va_arg(ap, long) : \ 651 flags&SIZEINT ? va_arg(ap, ssize_t) : \ 652 flags&SHORTINT ? (long)(short)va_arg(ap, int) : \ 653 (long)va_arg(ap, int)) 654 #define UARG() \ 655 (flags&QUADINT ? va_arg(ap, u_quad_t) : \ 656 flags&LONGINT ? va_arg(ap, u_long) : \ 657 flags&SIZEINT ? va_arg(ap, size_t) : \ 658 flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \ 659 (u_long)va_arg(ap, u_int)) 660 661 #define KPRINTF_PUTCHAR(C) do { \ 662 int chr = (C); \ 663 ret += 1; \ 664 if (oflags & TOBUFONLY) { \ 665 if ((vp != NULL) && (sbuf == tailp)) { \ 666 if (!(oflags & TOCOUNT)) \ 667 goto overflow; \ 668 } else \ 669 *sbuf++ = chr; \ 670 } else { \ 671 kputchar(chr, oflags, (struct tty *)vp); \ 672 } \ 673 } while(0) 674 675 int 676 kprintf(const char *fmt0, int oflags, void *vp, char *sbuf, va_list ap) 677 { 678 char *fmt; /* format string */ 679 int ch; /* character from fmt */ 680 int n; /* handy integer (short term usage) */ 681 char *cp = NULL; /* handy char pointer (short term usage) */ 682 int flags; /* flags as above */ 683 int ret; /* return value accumulator */ 684 int width; /* width from format (%8d), or 0 */ 685 int prec; /* precision from format (%.3d), or -1 */ 686 char sign; /* sign prefix (' ', '+', '-', or \0) */ 687 688 u_quad_t _uquad; /* integer arguments %[diouxX] */ 689 enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */ 690 int dprec; /* a copy of prec if [diouxX], 0 otherwise */ 691 int realsz; /* field size expanded by dprec */ 692 int size = 0; /* size of converted field or string */ 693 char *xdigs = NULL; /* digits for [xX] conversion */ 694 char buf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */ 695 char *tailp = NULL; /* tail pointer for snprintf */ 696 697 if ((oflags & TOBUFONLY) && (vp != NULL)) 698 tailp = *(char **)vp; 699 700 fmt = (char *)fmt0; 701 ret = 0; 702 703 /* 704 * Scan the format for conversions (`%' character). 705 */ 706 for (;;) { 707 while (*fmt != '%' && *fmt) { 708 KPRINTF_PUTCHAR(*fmt++); 709 } 710 if (*fmt == 0) 711 goto done; 712 713 fmt++; /* skip over '%' */ 714 715 flags = 0; 716 dprec = 0; 717 width = 0; 718 prec = -1; 719 sign = '\0'; 720 721 rflag: ch = *fmt++; 722 reswitch: switch (ch) { 723 /* XXX: non-standard '%b' format */ 724 case 'b': { 725 char *b, *z; 726 int tmp; 727 _uquad = UARG(); 728 b = va_arg(ap, char *); 729 if (*b == 8) 730 snprintf(buf, sizeof buf, "%llo", _uquad); 731 else if (*b == 10) 732 snprintf(buf, sizeof buf, "%lld", _uquad); 733 else if (*b == 16) 734 snprintf(buf, sizeof buf, "%llx", _uquad); 735 else 736 break; 737 b++; 738 739 z = buf; 740 while (*z) { 741 KPRINTF_PUTCHAR(*z++); 742 } 743 744 if (_uquad) { 745 tmp = 0; 746 while ((n = *b++) != 0) { 747 if (n & 0x80) 748 n &= 0x7f; 749 else if (n <= ' ') 750 n = n - 1; 751 if (_uquad & (1LL << n)) { 752 KPRINTF_PUTCHAR(tmp ? ',':'<'); 753 while (*b > ' ' && 754 (*b & 0x80) == 0) { 755 KPRINTF_PUTCHAR(*b); 756 b++; 757 } 758 tmp = 1; 759 } else { 760 while (*b > ' ' && 761 (*b & 0x80) == 0) 762 b++; 763 } 764 } 765 if (tmp) { 766 KPRINTF_PUTCHAR('>'); 767 } 768 } 769 continue; /* no output */ 770 } 771 772 case ' ': 773 /* 774 * ``If the space and + flags both appear, the space 775 * flag will be ignored.'' 776 * -- ANSI X3J11 777 */ 778 if (!sign) 779 sign = ' '; 780 goto rflag; 781 case '#': 782 flags |= ALT; 783 goto rflag; 784 case '*': 785 /* 786 * ``A negative field width argument is taken as a 787 * - flag followed by a positive field width.'' 788 * -- ANSI X3J11 789 * They don't exclude field widths read from args. 790 */ 791 if ((width = va_arg(ap, int)) >= 0) 792 goto rflag; 793 width = -width; 794 /* FALLTHROUGH */ 795 case '-': 796 flags |= LADJUST; 797 goto rflag; 798 case '+': 799 sign = '+'; 800 goto rflag; 801 case '.': 802 if ((ch = *fmt++) == '*') { 803 n = va_arg(ap, int); 804 prec = n < 0 ? -1 : n; 805 goto rflag; 806 } 807 n = 0; 808 while (is_digit(ch)) { 809 n = 10 * n + to_digit(ch); 810 ch = *fmt++; 811 } 812 prec = n < 0 ? -1 : n; 813 goto reswitch; 814 case '0': 815 /* 816 * ``Note that 0 is taken as a flag, not as the 817 * beginning of a field width.'' 818 * -- ANSI X3J11 819 */ 820 flags |= ZEROPAD; 821 goto rflag; 822 case '1': case '2': case '3': case '4': 823 case '5': case '6': case '7': case '8': case '9': 824 n = 0; 825 do { 826 n = 10 * n + to_digit(ch); 827 ch = *fmt++; 828 } while (is_digit(ch)); 829 width = n; 830 goto reswitch; 831 case 'h': 832 flags |= SHORTINT; 833 goto rflag; 834 case 'l': 835 if (*fmt == 'l') { 836 fmt++; 837 flags |= QUADINT; 838 } else { 839 flags |= LONGINT; 840 } 841 goto rflag; 842 case 'q': 843 flags |= QUADINT; 844 goto rflag; 845 case 'z': 846 flags |= SIZEINT; 847 goto rflag; 848 case 'c': 849 *(cp = buf) = va_arg(ap, int); 850 size = 1; 851 sign = '\0'; 852 break; 853 case 't': 854 /* ptrdiff_t */ 855 /* FALLTHROUGH */ 856 case 'D': 857 flags |= LONGINT; 858 /*FALLTHROUGH*/ 859 case 'd': 860 case 'i': 861 _uquad = SARG(); 862 if ((quad_t)_uquad < 0) { 863 _uquad = -_uquad; 864 sign = '-'; 865 } 866 base = DEC; 867 goto number; 868 case 'n': 869 /* %n is unsupported in the kernel; just skip it */ 870 if (flags & QUADINT) 871 (void)va_arg(ap, quad_t *); 872 else if (flags & LONGINT) 873 (void)va_arg(ap, long *); 874 else if (flags & SHORTINT) 875 (void)va_arg(ap, short *); 876 else if (flags & SIZEINT) 877 (void)va_arg(ap, ssize_t *); 878 else 879 (void)va_arg(ap, int *); 880 continue; /* no output */ 881 case 'O': 882 flags |= LONGINT; 883 /*FALLTHROUGH*/ 884 case 'o': 885 _uquad = UARG(); 886 base = OCT; 887 goto nosign; 888 case 'p': 889 /* 890 * ``The argument shall be a pointer to void. The 891 * value of the pointer is converted to a sequence 892 * of printable characters, in an implementation- 893 * defined manner.'' 894 * -- ANSI X3J11 895 */ 896 _uquad = (u_long)va_arg(ap, void *); 897 base = HEX; 898 xdigs = "0123456789abcdef"; 899 flags |= HEXPREFIX; 900 ch = 'x'; 901 goto nosign; 902 case 's': 903 if ((cp = va_arg(ap, char *)) == NULL) 904 cp = "(null)"; 905 if (prec >= 0) { 906 /* 907 * can't use strlen; can only look for the 908 * NUL in the first `prec' characters, and 909 * strlen() will go further. 910 */ 911 char *p = memchr(cp, 0, prec); 912 913 if (p != NULL) { 914 size = p - cp; 915 if (size > prec) 916 size = prec; 917 } else 918 size = prec; 919 } else 920 size = strlen(cp); 921 sign = '\0'; 922 break; 923 case 'U': 924 flags |= LONGINT; 925 /*FALLTHROUGH*/ 926 case 'u': 927 _uquad = UARG(); 928 base = DEC; 929 goto nosign; 930 case 'X': 931 xdigs = "0123456789ABCDEF"; 932 goto hex; 933 case 'x': 934 xdigs = "0123456789abcdef"; 935 hex: _uquad = UARG(); 936 base = HEX; 937 /* leading 0x/X only if non-zero */ 938 if (flags & ALT && _uquad != 0) 939 flags |= HEXPREFIX; 940 941 /* unsigned conversions */ 942 nosign: sign = '\0'; 943 /* 944 * ``... diouXx conversions ... if a precision is 945 * specified, the 0 flag will be ignored.'' 946 * -- ANSI X3J11 947 */ 948 number: if ((dprec = prec) >= 0) 949 flags &= ~ZEROPAD; 950 951 /* 952 * ``The result of converting a zero value with an 953 * explicit precision of zero is no characters.'' 954 * -- ANSI X3J11 955 */ 956 cp = buf + KPRINTF_BUFSIZE; 957 if (_uquad != 0 || prec != 0) { 958 /* 959 * Unsigned mod is hard, and unsigned mod 960 * by a constant is easier than that by 961 * a variable; hence this switch. 962 */ 963 switch (base) { 964 case OCT: 965 do { 966 *--cp = to_char(_uquad & 7); 967 _uquad >>= 3; 968 } while (_uquad); 969 /* handle octal leading 0 */ 970 if (flags & ALT && *cp != '0') 971 *--cp = '0'; 972 break; 973 974 case DEC: 975 /* many numbers are 1 digit */ 976 while (_uquad >= 10) { 977 *--cp = to_char(_uquad % 10); 978 _uquad /= 10; 979 } 980 *--cp = to_char(_uquad); 981 break; 982 983 case HEX: 984 do { 985 *--cp = xdigs[_uquad & 15]; 986 _uquad >>= 4; 987 } while (_uquad); 988 break; 989 990 default: 991 cp = "bug in kprintf: bad base"; 992 size = strlen(cp); 993 goto skipsize; 994 } 995 } 996 size = buf + KPRINTF_BUFSIZE - cp; 997 skipsize: 998 break; 999 default: /* "%?" prints ?, unless ? is NUL */ 1000 if (ch == '\0') 1001 goto done; 1002 /* pretend it was %c with argument ch */ 1003 cp = buf; 1004 *cp = ch; 1005 size = 1; 1006 sign = '\0'; 1007 break; 1008 } 1009 1010 /* 1011 * All reasonable formats wind up here. At this point, `cp' 1012 * points to a string which (if not flags&LADJUST) should be 1013 * padded out to `width' places. If flags&ZEROPAD, it should 1014 * first be prefixed by any sign or other prefix; otherwise, 1015 * it should be blank padded before the prefix is emitted. 1016 * After any left-hand padding and prefixing, emit zeroes 1017 * required by a decimal [diouxX] precision, then print the 1018 * string proper, then emit zeroes required by any leftover 1019 * floating precision; finally, if LADJUST, pad with blanks. 1020 * 1021 * Compute actual size, so we know how much to pad. 1022 * size excludes decimal prec; realsz includes it. 1023 */ 1024 realsz = dprec > size ? dprec : size; 1025 if (sign) 1026 realsz++; 1027 else if (flags & HEXPREFIX) 1028 realsz+= 2; 1029 1030 /* right-adjusting blank padding */ 1031 if ((flags & (LADJUST|ZEROPAD)) == 0) { 1032 n = width - realsz; 1033 while (n-- > 0) 1034 KPRINTF_PUTCHAR(' '); 1035 } 1036 1037 /* prefix */ 1038 if (sign) { 1039 KPRINTF_PUTCHAR(sign); 1040 } else if (flags & HEXPREFIX) { 1041 KPRINTF_PUTCHAR('0'); 1042 KPRINTF_PUTCHAR(ch); 1043 } 1044 1045 /* right-adjusting zero padding */ 1046 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) { 1047 n = width - realsz; 1048 while (n-- > 0) 1049 KPRINTF_PUTCHAR('0'); 1050 } 1051 1052 /* leading zeroes from decimal precision */ 1053 n = dprec - size; 1054 while (n-- > 0) 1055 KPRINTF_PUTCHAR('0'); 1056 1057 /* the string or number proper */ 1058 while (size--) 1059 KPRINTF_PUTCHAR(*cp++); 1060 /* left-adjusting padding (always blank) */ 1061 if (flags & LADJUST) { 1062 n = width - realsz; 1063 while (n-- > 0) 1064 KPRINTF_PUTCHAR(' '); 1065 } 1066 } 1067 1068 done: 1069 if ((oflags & TOBUFONLY) && (vp != NULL)) 1070 *(char **)vp = sbuf; 1071 overflow: 1072 return (ret); 1073 /* NOTREACHED */ 1074 } 1075 1076 #if __GNUC_PREREQ__(2,96) 1077 /* 1078 * XXX - these functions shouldn't be in the kernel, but gcc 3.X feels like 1079 * translating some printf calls to puts and since it doesn't seem 1080 * possible to just turn off parts of those optimizations (some of 1081 * them are really useful), we have to provide a dummy puts and putchar 1082 * that are wrappers around printf. 1083 */ 1084 int puts(const char *); 1085 int putchar(int c); 1086 1087 int 1088 puts(const char *str) 1089 { 1090 printf("%s\n", str); 1091 1092 return (0); 1093 } 1094 1095 int 1096 putchar(int c) 1097 { 1098 printf("%c", c); 1099 1100 return (c); 1101 } 1102 1103 1104 #endif 1105