1 /* 2 * linux/lib/vsprintf.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 */ 6 7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ 8 /* 9 * Wirzenius wrote this portably, Torvalds fucked it up :-) 10 */ 11 12 /* 13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com> 14 * - changed to provide snprintf and vsnprintf functions 15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> 16 * - scnprintf and vscnprintf 17 */ 18 19 #include <stdarg.h> 20 #include <linux/module.h> 21 #include <linux/types.h> 22 #include <linux/string.h> 23 #include <linux/ctype.h> 24 #include <linux/kernel.h> 25 #include <linux/kallsyms.h> 26 #include <linux/uaccess.h> 27 #include <linux/ioport.h> 28 #include <net/addrconf.h> 29 30 #include <asm/page.h> /* for PAGE_SIZE */ 31 #include <asm/div64.h> 32 #include <asm/sections.h> /* for dereference_function_descriptor() */ 33 34 /* Works only for digits and letters, but small and fast */ 35 #define TOLOWER(x) ((x) | 0x20) 36 37 static unsigned int simple_guess_base(const char *cp) 38 { 39 if (cp[0] == '0') { 40 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2])) 41 return 16; 42 else 43 return 8; 44 } else { 45 return 10; 46 } 47 } 48 49 /** 50 * simple_strtoull - convert a string to an unsigned long long 51 * @cp: The start of the string 52 * @endp: A pointer to the end of the parsed string will be placed here 53 * @base: The number base to use 54 */ 55 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 56 { 57 unsigned long long result = 0; 58 59 if (!base) 60 base = simple_guess_base(cp); 61 62 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x') 63 cp += 2; 64 65 while (isxdigit(*cp)) { 66 unsigned int value; 67 68 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10; 69 if (value >= base) 70 break; 71 result = result * base + value; 72 cp++; 73 } 74 if (endp) 75 *endp = (char *)cp; 76 77 return result; 78 } 79 EXPORT_SYMBOL(simple_strtoull); 80 81 /** 82 * simple_strtoul - convert a string to an unsigned long 83 * @cp: The start of the string 84 * @endp: A pointer to the end of the parsed string will be placed here 85 * @base: The number base to use 86 */ 87 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 88 { 89 return simple_strtoull(cp, endp, base); 90 } 91 EXPORT_SYMBOL(simple_strtoul); 92 93 /** 94 * simple_strtol - convert a string to a signed long 95 * @cp: The start of the string 96 * @endp: A pointer to the end of the parsed string will be placed here 97 * @base: The number base to use 98 */ 99 long simple_strtol(const char *cp, char **endp, unsigned int base) 100 { 101 if (*cp == '-') 102 return -simple_strtoul(cp + 1, endp, base); 103 104 return simple_strtoul(cp, endp, base); 105 } 106 EXPORT_SYMBOL(simple_strtol); 107 108 /** 109 * simple_strtoll - convert a string to a signed long long 110 * @cp: The start of the string 111 * @endp: A pointer to the end of the parsed string will be placed here 112 * @base: The number base to use 113 */ 114 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 115 { 116 if (*cp == '-') 117 return -simple_strtoull(cp + 1, endp, base); 118 119 return simple_strtoull(cp, endp, base); 120 } 121 EXPORT_SYMBOL(simple_strtoll); 122 123 /** 124 * strict_strtoul - convert a string to an unsigned long strictly 125 * @cp: The string to be converted 126 * @base: The number base to use 127 * @res: The converted result value 128 * 129 * strict_strtoul converts a string to an unsigned long only if the 130 * string is really an unsigned long string, any string containing 131 * any invalid char at the tail will be rejected and -EINVAL is returned, 132 * only a newline char at the tail is acceptible because people generally 133 * change a module parameter in the following way: 134 * 135 * echo 1024 > /sys/module/e1000/parameters/copybreak 136 * 137 * echo will append a newline to the tail. 138 * 139 * It returns 0 if conversion is successful and *res is set to the converted 140 * value, otherwise it returns -EINVAL and *res is set to 0. 141 * 142 * simple_strtoul just ignores the successive invalid characters and 143 * return the converted value of prefix part of the string. 144 */ 145 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res) 146 { 147 char *tail; 148 unsigned long val; 149 150 *res = 0; 151 if (!*cp) 152 return -EINVAL; 153 154 val = simple_strtoul(cp, &tail, base); 155 if (tail == cp) 156 return -EINVAL; 157 158 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) { 159 *res = val; 160 return 0; 161 } 162 163 return -EINVAL; 164 } 165 EXPORT_SYMBOL(strict_strtoul); 166 167 /** 168 * strict_strtol - convert a string to a long strictly 169 * @cp: The string to be converted 170 * @base: The number base to use 171 * @res: The converted result value 172 * 173 * strict_strtol is similiar to strict_strtoul, but it allows the first 174 * character of a string is '-'. 175 * 176 * It returns 0 if conversion is successful and *res is set to the converted 177 * value, otherwise it returns -EINVAL and *res is set to 0. 178 */ 179 int strict_strtol(const char *cp, unsigned int base, long *res) 180 { 181 int ret; 182 if (*cp == '-') { 183 ret = strict_strtoul(cp + 1, base, (unsigned long *)res); 184 if (!ret) 185 *res = -(*res); 186 } else { 187 ret = strict_strtoul(cp, base, (unsigned long *)res); 188 } 189 190 return ret; 191 } 192 EXPORT_SYMBOL(strict_strtol); 193 194 /** 195 * strict_strtoull - convert a string to an unsigned long long strictly 196 * @cp: The string to be converted 197 * @base: The number base to use 198 * @res: The converted result value 199 * 200 * strict_strtoull converts a string to an unsigned long long only if the 201 * string is really an unsigned long long string, any string containing 202 * any invalid char at the tail will be rejected and -EINVAL is returned, 203 * only a newline char at the tail is acceptible because people generally 204 * change a module parameter in the following way: 205 * 206 * echo 1024 > /sys/module/e1000/parameters/copybreak 207 * 208 * echo will append a newline to the tail of the string. 209 * 210 * It returns 0 if conversion is successful and *res is set to the converted 211 * value, otherwise it returns -EINVAL and *res is set to 0. 212 * 213 * simple_strtoull just ignores the successive invalid characters and 214 * return the converted value of prefix part of the string. 215 */ 216 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res) 217 { 218 char *tail; 219 unsigned long long val; 220 221 *res = 0; 222 if (!*cp) 223 return -EINVAL; 224 225 val = simple_strtoull(cp, &tail, base); 226 if (tail == cp) 227 return -EINVAL; 228 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) { 229 *res = val; 230 return 0; 231 } 232 233 return -EINVAL; 234 } 235 EXPORT_SYMBOL(strict_strtoull); 236 237 /** 238 * strict_strtoll - convert a string to a long long strictly 239 * @cp: The string to be converted 240 * @base: The number base to use 241 * @res: The converted result value 242 * 243 * strict_strtoll is similiar to strict_strtoull, but it allows the first 244 * character of a string is '-'. 245 * 246 * It returns 0 if conversion is successful and *res is set to the converted 247 * value, otherwise it returns -EINVAL and *res is set to 0. 248 */ 249 int strict_strtoll(const char *cp, unsigned int base, long long *res) 250 { 251 int ret; 252 if (*cp == '-') { 253 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res); 254 if (!ret) 255 *res = -(*res); 256 } else { 257 ret = strict_strtoull(cp, base, (unsigned long long *)res); 258 } 259 260 return ret; 261 } 262 EXPORT_SYMBOL(strict_strtoll); 263 264 static noinline_for_stack 265 int skip_atoi(const char **s) 266 { 267 int i = 0; 268 269 while (isdigit(**s)) 270 i = i*10 + *((*s)++) - '0'; 271 272 return i; 273 } 274 275 /* Decimal conversion is by far the most typical, and is used 276 * for /proc and /sys data. This directly impacts e.g. top performance 277 * with many processes running. We optimize it for speed 278 * using code from 279 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html 280 * (with permission from the author, Douglas W. Jones). */ 281 282 /* Formats correctly any integer in [0,99999]. 283 * Outputs from one to five digits depending on input. 284 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ 285 static noinline_for_stack 286 char *put_dec_trunc(char *buf, unsigned q) 287 { 288 unsigned d3, d2, d1, d0; 289 d1 = (q>>4) & 0xf; 290 d2 = (q>>8) & 0xf; 291 d3 = (q>>12); 292 293 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 294 q = (d0 * 0xcd) >> 11; 295 d0 = d0 - 10*q; 296 *buf++ = d0 + '0'; /* least significant digit */ 297 d1 = q + 9*d3 + 5*d2 + d1; 298 if (d1 != 0) { 299 q = (d1 * 0xcd) >> 11; 300 d1 = d1 - 10*q; 301 *buf++ = d1 + '0'; /* next digit */ 302 303 d2 = q + 2*d2; 304 if ((d2 != 0) || (d3 != 0)) { 305 q = (d2 * 0xd) >> 7; 306 d2 = d2 - 10*q; 307 *buf++ = d2 + '0'; /* next digit */ 308 309 d3 = q + 4*d3; 310 if (d3 != 0) { 311 q = (d3 * 0xcd) >> 11; 312 d3 = d3 - 10*q; 313 *buf++ = d3 + '0'; /* next digit */ 314 if (q != 0) 315 *buf++ = q + '0'; /* most sign. digit */ 316 } 317 } 318 } 319 320 return buf; 321 } 322 /* Same with if's removed. Always emits five digits */ 323 static noinline_for_stack 324 char *put_dec_full(char *buf, unsigned q) 325 { 326 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ 327 /* but anyway, gcc produces better code with full-sized ints */ 328 unsigned d3, d2, d1, d0; 329 d1 = (q>>4) & 0xf; 330 d2 = (q>>8) & 0xf; 331 d3 = (q>>12); 332 333 /* 334 * Possible ways to approx. divide by 10 335 * gcc -O2 replaces multiply with shifts and adds 336 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) 337 * (x * 0x67) >> 10: 1100111 338 * (x * 0x34) >> 9: 110100 - same 339 * (x * 0x1a) >> 8: 11010 - same 340 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) 341 */ 342 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 343 q = (d0 * 0xcd) >> 11; 344 d0 = d0 - 10*q; 345 *buf++ = d0 + '0'; 346 d1 = q + 9*d3 + 5*d2 + d1; 347 q = (d1 * 0xcd) >> 11; 348 d1 = d1 - 10*q; 349 *buf++ = d1 + '0'; 350 351 d2 = q + 2*d2; 352 q = (d2 * 0xd) >> 7; 353 d2 = d2 - 10*q; 354 *buf++ = d2 + '0'; 355 356 d3 = q + 4*d3; 357 q = (d3 * 0xcd) >> 11; /* - shorter code */ 358 /* q = (d3 * 0x67) >> 10; - would also work */ 359 d3 = d3 - 10*q; 360 *buf++ = d3 + '0'; 361 *buf++ = q + '0'; 362 363 return buf; 364 } 365 /* No inlining helps gcc to use registers better */ 366 static noinline_for_stack 367 char *put_dec(char *buf, unsigned long long num) 368 { 369 while (1) { 370 unsigned rem; 371 if (num < 100000) 372 return put_dec_trunc(buf, num); 373 rem = do_div(num, 100000); 374 buf = put_dec_full(buf, rem); 375 } 376 } 377 378 #define ZEROPAD 1 /* pad with zero */ 379 #define SIGN 2 /* unsigned/signed long */ 380 #define PLUS 4 /* show plus */ 381 #define SPACE 8 /* space if plus */ 382 #define LEFT 16 /* left justified */ 383 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 384 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 385 386 enum format_type { 387 FORMAT_TYPE_NONE, /* Just a string part */ 388 FORMAT_TYPE_WIDTH, 389 FORMAT_TYPE_PRECISION, 390 FORMAT_TYPE_CHAR, 391 FORMAT_TYPE_STR, 392 FORMAT_TYPE_PTR, 393 FORMAT_TYPE_PERCENT_CHAR, 394 FORMAT_TYPE_INVALID, 395 FORMAT_TYPE_LONG_LONG, 396 FORMAT_TYPE_ULONG, 397 FORMAT_TYPE_LONG, 398 FORMAT_TYPE_UBYTE, 399 FORMAT_TYPE_BYTE, 400 FORMAT_TYPE_USHORT, 401 FORMAT_TYPE_SHORT, 402 FORMAT_TYPE_UINT, 403 FORMAT_TYPE_INT, 404 FORMAT_TYPE_NRCHARS, 405 FORMAT_TYPE_SIZE_T, 406 FORMAT_TYPE_PTRDIFF 407 }; 408 409 struct printf_spec { 410 u8 type; /* format_type enum */ 411 u8 flags; /* flags to number() */ 412 u8 base; /* number base, 8, 10 or 16 only */ 413 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ 414 s16 field_width; /* width of output field */ 415 s16 precision; /* # of digits/chars */ 416 }; 417 418 static noinline_for_stack 419 char *number(char *buf, char *end, unsigned long long num, 420 struct printf_spec spec) 421 { 422 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 423 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 424 425 char tmp[66]; 426 char sign; 427 char locase; 428 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 429 int i; 430 431 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 432 * produces same digits or (maybe lowercased) letters */ 433 locase = (spec.flags & SMALL); 434 if (spec.flags & LEFT) 435 spec.flags &= ~ZEROPAD; 436 sign = 0; 437 if (spec.flags & SIGN) { 438 if ((signed long long)num < 0) { 439 sign = '-'; 440 num = -(signed long long)num; 441 spec.field_width--; 442 } else if (spec.flags & PLUS) { 443 sign = '+'; 444 spec.field_width--; 445 } else if (spec.flags & SPACE) { 446 sign = ' '; 447 spec.field_width--; 448 } 449 } 450 if (need_pfx) { 451 spec.field_width--; 452 if (spec.base == 16) 453 spec.field_width--; 454 } 455 456 /* generate full string in tmp[], in reverse order */ 457 i = 0; 458 if (num == 0) 459 tmp[i++] = '0'; 460 /* Generic code, for any base: 461 else do { 462 tmp[i++] = (digits[do_div(num,base)] | locase); 463 } while (num != 0); 464 */ 465 else if (spec.base != 10) { /* 8 or 16 */ 466 int mask = spec.base - 1; 467 int shift = 3; 468 469 if (spec.base == 16) 470 shift = 4; 471 do { 472 tmp[i++] = (digits[((unsigned char)num) & mask] | locase); 473 num >>= shift; 474 } while (num); 475 } else { /* base 10 */ 476 i = put_dec(tmp, num) - tmp; 477 } 478 479 /* printing 100 using %2d gives "100", not "00" */ 480 if (i > spec.precision) 481 spec.precision = i; 482 /* leading space padding */ 483 spec.field_width -= spec.precision; 484 if (!(spec.flags & (ZEROPAD+LEFT))) { 485 while (--spec.field_width >= 0) { 486 if (buf < end) 487 *buf = ' '; 488 ++buf; 489 } 490 } 491 /* sign */ 492 if (sign) { 493 if (buf < end) 494 *buf = sign; 495 ++buf; 496 } 497 /* "0x" / "0" prefix */ 498 if (need_pfx) { 499 if (buf < end) 500 *buf = '0'; 501 ++buf; 502 if (spec.base == 16) { 503 if (buf < end) 504 *buf = ('X' | locase); 505 ++buf; 506 } 507 } 508 /* zero or space padding */ 509 if (!(spec.flags & LEFT)) { 510 char c = (spec.flags & ZEROPAD) ? '0' : ' '; 511 while (--spec.field_width >= 0) { 512 if (buf < end) 513 *buf = c; 514 ++buf; 515 } 516 } 517 /* hmm even more zero padding? */ 518 while (i <= --spec.precision) { 519 if (buf < end) 520 *buf = '0'; 521 ++buf; 522 } 523 /* actual digits of result */ 524 while (--i >= 0) { 525 if (buf < end) 526 *buf = tmp[i]; 527 ++buf; 528 } 529 /* trailing space padding */ 530 while (--spec.field_width >= 0) { 531 if (buf < end) 532 *buf = ' '; 533 ++buf; 534 } 535 536 return buf; 537 } 538 539 static noinline_for_stack 540 char *string(char *buf, char *end, const char *s, struct printf_spec spec) 541 { 542 int len, i; 543 544 if ((unsigned long)s < PAGE_SIZE) 545 s = "(null)"; 546 547 len = strnlen(s, spec.precision); 548 549 if (!(spec.flags & LEFT)) { 550 while (len < spec.field_width--) { 551 if (buf < end) 552 *buf = ' '; 553 ++buf; 554 } 555 } 556 for (i = 0; i < len; ++i) { 557 if (buf < end) 558 *buf = *s; 559 ++buf; ++s; 560 } 561 while (len < spec.field_width--) { 562 if (buf < end) 563 *buf = ' '; 564 ++buf; 565 } 566 567 return buf; 568 } 569 570 static noinline_for_stack 571 char *symbol_string(char *buf, char *end, void *ptr, 572 struct printf_spec spec, char ext) 573 { 574 unsigned long value = (unsigned long) ptr; 575 #ifdef CONFIG_KALLSYMS 576 char sym[KSYM_SYMBOL_LEN]; 577 if (ext != 'f' && ext != 's') 578 sprint_symbol(sym, value); 579 else 580 kallsyms_lookup(value, NULL, NULL, NULL, sym); 581 582 return string(buf, end, sym, spec); 583 #else 584 spec.field_width = 2 * sizeof(void *); 585 spec.flags |= SPECIAL | SMALL | ZEROPAD; 586 spec.base = 16; 587 588 return number(buf, end, value, spec); 589 #endif 590 } 591 592 static noinline_for_stack 593 char *resource_string(char *buf, char *end, struct resource *res, 594 struct printf_spec spec, const char *fmt) 595 { 596 #ifndef IO_RSRC_PRINTK_SIZE 597 #define IO_RSRC_PRINTK_SIZE 6 598 #endif 599 600 #ifndef MEM_RSRC_PRINTK_SIZE 601 #define MEM_RSRC_PRINTK_SIZE 10 602 #endif 603 static const struct printf_spec io_spec = { 604 .base = 16, 605 .field_width = IO_RSRC_PRINTK_SIZE, 606 .precision = -1, 607 .flags = SPECIAL | SMALL | ZEROPAD, 608 }; 609 static const struct printf_spec mem_spec = { 610 .base = 16, 611 .field_width = MEM_RSRC_PRINTK_SIZE, 612 .precision = -1, 613 .flags = SPECIAL | SMALL | ZEROPAD, 614 }; 615 static const struct printf_spec bus_spec = { 616 .base = 16, 617 .field_width = 2, 618 .precision = -1, 619 .flags = SMALL | ZEROPAD, 620 }; 621 static const struct printf_spec dec_spec = { 622 .base = 10, 623 .precision = -1, 624 .flags = 0, 625 }; 626 static const struct printf_spec str_spec = { 627 .field_width = -1, 628 .precision = 10, 629 .flags = LEFT, 630 }; 631 static const struct printf_spec flag_spec = { 632 .base = 16, 633 .precision = -1, 634 .flags = SPECIAL | SMALL, 635 }; 636 637 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 638 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 639 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 640 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 641 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 642 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 643 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 644 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 645 646 char *p = sym, *pend = sym + sizeof(sym); 647 int decode = (fmt[0] == 'R') ? 1 : 0; 648 const struct printf_spec *specp; 649 650 *p++ = '['; 651 if (res->flags & IORESOURCE_IO) { 652 p = string(p, pend, "io ", str_spec); 653 specp = &io_spec; 654 } else if (res->flags & IORESOURCE_MEM) { 655 p = string(p, pend, "mem ", str_spec); 656 specp = &mem_spec; 657 } else if (res->flags & IORESOURCE_IRQ) { 658 p = string(p, pend, "irq ", str_spec); 659 specp = &dec_spec; 660 } else if (res->flags & IORESOURCE_DMA) { 661 p = string(p, pend, "dma ", str_spec); 662 specp = &dec_spec; 663 } else if (res->flags & IORESOURCE_BUS) { 664 p = string(p, pend, "bus ", str_spec); 665 specp = &bus_spec; 666 } else { 667 p = string(p, pend, "??? ", str_spec); 668 specp = &mem_spec; 669 decode = 0; 670 } 671 p = number(p, pend, res->start, *specp); 672 if (res->start != res->end) { 673 *p++ = '-'; 674 p = number(p, pend, res->end, *specp); 675 } 676 if (decode) { 677 if (res->flags & IORESOURCE_MEM_64) 678 p = string(p, pend, " 64bit", str_spec); 679 if (res->flags & IORESOURCE_PREFETCH) 680 p = string(p, pend, " pref", str_spec); 681 if (res->flags & IORESOURCE_WINDOW) 682 p = string(p, pend, " window", str_spec); 683 if (res->flags & IORESOURCE_DISABLED) 684 p = string(p, pend, " disabled", str_spec); 685 } else { 686 p = string(p, pend, " flags ", str_spec); 687 p = number(p, pend, res->flags, flag_spec); 688 } 689 *p++ = ']'; 690 *p = '\0'; 691 692 return string(buf, end, sym, spec); 693 } 694 695 static noinline_for_stack 696 char *mac_address_string(char *buf, char *end, u8 *addr, 697 struct printf_spec spec, const char *fmt) 698 { 699 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 700 char *p = mac_addr; 701 int i; 702 char separator; 703 704 if (fmt[1] == 'F') { /* FDDI canonical format */ 705 separator = '-'; 706 } else { 707 separator = ':'; 708 } 709 710 for (i = 0; i < 6; i++) { 711 p = pack_hex_byte(p, addr[i]); 712 if (fmt[0] == 'M' && i != 5) 713 *p++ = separator; 714 } 715 *p = '\0'; 716 717 return string(buf, end, mac_addr, spec); 718 } 719 720 static noinline_for_stack 721 char *ip4_string(char *p, const u8 *addr, const char *fmt) 722 { 723 int i; 724 bool leading_zeros = (fmt[0] == 'i'); 725 int index; 726 int step; 727 728 switch (fmt[2]) { 729 case 'h': 730 #ifdef __BIG_ENDIAN 731 index = 0; 732 step = 1; 733 #else 734 index = 3; 735 step = -1; 736 #endif 737 break; 738 case 'l': 739 index = 3; 740 step = -1; 741 break; 742 case 'n': 743 case 'b': 744 default: 745 index = 0; 746 step = 1; 747 break; 748 } 749 for (i = 0; i < 4; i++) { 750 char temp[3]; /* hold each IP quad in reverse order */ 751 int digits = put_dec_trunc(temp, addr[index]) - temp; 752 if (leading_zeros) { 753 if (digits < 3) 754 *p++ = '0'; 755 if (digits < 2) 756 *p++ = '0'; 757 } 758 /* reverse the digits in the quad */ 759 while (digits--) 760 *p++ = temp[digits]; 761 if (i < 3) 762 *p++ = '.'; 763 index += step; 764 } 765 *p = '\0'; 766 767 return p; 768 } 769 770 static noinline_for_stack 771 char *ip6_compressed_string(char *p, const char *addr) 772 { 773 int i, j, range; 774 unsigned char zerolength[8]; 775 int longest = 1; 776 int colonpos = -1; 777 u16 word; 778 u8 hi, lo; 779 bool needcolon = false; 780 bool useIPv4; 781 struct in6_addr in6; 782 783 memcpy(&in6, addr, sizeof(struct in6_addr)); 784 785 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 786 787 memset(zerolength, 0, sizeof(zerolength)); 788 789 if (useIPv4) 790 range = 6; 791 else 792 range = 8; 793 794 /* find position of longest 0 run */ 795 for (i = 0; i < range; i++) { 796 for (j = i; j < range; j++) { 797 if (in6.s6_addr16[j] != 0) 798 break; 799 zerolength[i]++; 800 } 801 } 802 for (i = 0; i < range; i++) { 803 if (zerolength[i] > longest) { 804 longest = zerolength[i]; 805 colonpos = i; 806 } 807 } 808 809 /* emit address */ 810 for (i = 0; i < range; i++) { 811 if (i == colonpos) { 812 if (needcolon || i == 0) 813 *p++ = ':'; 814 *p++ = ':'; 815 needcolon = false; 816 i += longest - 1; 817 continue; 818 } 819 if (needcolon) { 820 *p++ = ':'; 821 needcolon = false; 822 } 823 /* hex u16 without leading 0s */ 824 word = ntohs(in6.s6_addr16[i]); 825 hi = word >> 8; 826 lo = word & 0xff; 827 if (hi) { 828 if (hi > 0x0f) 829 p = pack_hex_byte(p, hi); 830 else 831 *p++ = hex_asc_lo(hi); 832 p = pack_hex_byte(p, lo); 833 } 834 else if (lo > 0x0f) 835 p = pack_hex_byte(p, lo); 836 else 837 *p++ = hex_asc_lo(lo); 838 needcolon = true; 839 } 840 841 if (useIPv4) { 842 if (needcolon) 843 *p++ = ':'; 844 p = ip4_string(p, &in6.s6_addr[12], "I4"); 845 } 846 *p = '\0'; 847 848 return p; 849 } 850 851 static noinline_for_stack 852 char *ip6_string(char *p, const char *addr, const char *fmt) 853 { 854 int i; 855 856 for (i = 0; i < 8; i++) { 857 p = pack_hex_byte(p, *addr++); 858 p = pack_hex_byte(p, *addr++); 859 if (fmt[0] == 'I' && i != 7) 860 *p++ = ':'; 861 } 862 *p = '\0'; 863 864 return p; 865 } 866 867 static noinline_for_stack 868 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 869 struct printf_spec spec, const char *fmt) 870 { 871 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 872 873 if (fmt[0] == 'I' && fmt[2] == 'c') 874 ip6_compressed_string(ip6_addr, addr); 875 else 876 ip6_string(ip6_addr, addr, fmt); 877 878 return string(buf, end, ip6_addr, spec); 879 } 880 881 static noinline_for_stack 882 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 883 struct printf_spec spec, const char *fmt) 884 { 885 char ip4_addr[sizeof("255.255.255.255")]; 886 887 ip4_string(ip4_addr, addr, fmt); 888 889 return string(buf, end, ip4_addr, spec); 890 } 891 892 static noinline_for_stack 893 char *uuid_string(char *buf, char *end, const u8 *addr, 894 struct printf_spec spec, const char *fmt) 895 { 896 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 897 char *p = uuid; 898 int i; 899 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 900 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 901 const u8 *index = be; 902 bool uc = false; 903 904 switch (*(++fmt)) { 905 case 'L': 906 uc = true; /* fall-through */ 907 case 'l': 908 index = le; 909 break; 910 case 'B': 911 uc = true; 912 break; 913 } 914 915 for (i = 0; i < 16; i++) { 916 p = pack_hex_byte(p, addr[index[i]]); 917 switch (i) { 918 case 3: 919 case 5: 920 case 7: 921 case 9: 922 *p++ = '-'; 923 break; 924 } 925 } 926 927 *p = 0; 928 929 if (uc) { 930 p = uuid; 931 do { 932 *p = toupper(*p); 933 } while (*(++p)); 934 } 935 936 return string(buf, end, uuid, spec); 937 } 938 939 /* 940 * Show a '%p' thing. A kernel extension is that the '%p' is followed 941 * by an extra set of alphanumeric characters that are extended format 942 * specifiers. 943 * 944 * Right now we handle: 945 * 946 * - 'F' For symbolic function descriptor pointers with offset 947 * - 'f' For simple symbolic function names without offset 948 * - 'S' For symbolic direct pointers with offset 949 * - 's' For symbolic direct pointers without offset 950 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 951 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 952 * - 'M' For a 6-byte MAC address, it prints the address in the 953 * usual colon-separated hex notation 954 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 955 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 956 * with a dash-separated hex notation 957 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 958 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 959 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 960 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 961 * IPv6 omits the colons (01020304...0f) 962 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 963 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 964 * - 'I6c' for IPv6 addresses printed as specified by 965 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 966 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 967 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 968 * Options for %pU are: 969 * b big endian lower case hex (default) 970 * B big endian UPPER case hex 971 * l little endian lower case hex 972 * L little endian UPPER case hex 973 * big endian output byte order is: 974 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 975 * little endian output byte order is: 976 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 977 * - 'V' For a struct va_format which contains a format string * and va_list *, 978 * call vsnprintf(->format, *->va_list). 979 * Implements a "recursive vsnprintf". 980 * Do not use this feature without some mechanism to verify the 981 * correctness of the format string and va_list arguments. 982 * 983 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 984 * function pointers are really function descriptors, which contain a 985 * pointer to the real address. 986 */ 987 static noinline_for_stack 988 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 989 struct printf_spec spec) 990 { 991 if (!ptr) { 992 /* 993 * Print (null) with the same width as a pointer so it makes 994 * tabular output look nice. 995 */ 996 if (spec.field_width == -1) 997 spec.field_width = 2 * sizeof(void *); 998 return string(buf, end, "(null)", spec); 999 } 1000 1001 switch (*fmt) { 1002 case 'F': 1003 case 'f': 1004 ptr = dereference_function_descriptor(ptr); 1005 /* Fallthrough */ 1006 case 'S': 1007 case 's': 1008 return symbol_string(buf, end, ptr, spec, *fmt); 1009 case 'R': 1010 case 'r': 1011 return resource_string(buf, end, ptr, spec, fmt); 1012 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 1013 case 'm': /* Contiguous: 000102030405 */ 1014 /* [mM]F (FDDI, bit reversed) */ 1015 return mac_address_string(buf, end, ptr, spec, fmt); 1016 case 'I': /* Formatted IP supported 1017 * 4: 1.2.3.4 1018 * 6: 0001:0203:...:0708 1019 * 6c: 1::708 or 1::1.2.3.4 1020 */ 1021 case 'i': /* Contiguous: 1022 * 4: 001.002.003.004 1023 * 6: 000102...0f 1024 */ 1025 switch (fmt[1]) { 1026 case '6': 1027 return ip6_addr_string(buf, end, ptr, spec, fmt); 1028 case '4': 1029 return ip4_addr_string(buf, end, ptr, spec, fmt); 1030 } 1031 break; 1032 case 'U': 1033 return uuid_string(buf, end, ptr, spec, fmt); 1034 case 'V': 1035 return buf + vsnprintf(buf, end - buf, 1036 ((struct va_format *)ptr)->fmt, 1037 *(((struct va_format *)ptr)->va)); 1038 } 1039 spec.flags |= SMALL; 1040 if (spec.field_width == -1) { 1041 spec.field_width = 2 * sizeof(void *); 1042 spec.flags |= ZEROPAD; 1043 } 1044 spec.base = 16; 1045 1046 return number(buf, end, (unsigned long) ptr, spec); 1047 } 1048 1049 /* 1050 * Helper function to decode printf style format. 1051 * Each call decode a token from the format and return the 1052 * number of characters read (or likely the delta where it wants 1053 * to go on the next call). 1054 * The decoded token is returned through the parameters 1055 * 1056 * 'h', 'l', or 'L' for integer fields 1057 * 'z' support added 23/7/1999 S.H. 1058 * 'z' changed to 'Z' --davidm 1/25/99 1059 * 't' added for ptrdiff_t 1060 * 1061 * @fmt: the format string 1062 * @type of the token returned 1063 * @flags: various flags such as +, -, # tokens.. 1064 * @field_width: overwritten width 1065 * @base: base of the number (octal, hex, ...) 1066 * @precision: precision of a number 1067 * @qualifier: qualifier of a number (long, size_t, ...) 1068 */ 1069 static noinline_for_stack 1070 int format_decode(const char *fmt, struct printf_spec *spec) 1071 { 1072 const char *start = fmt; 1073 1074 /* we finished early by reading the field width */ 1075 if (spec->type == FORMAT_TYPE_WIDTH) { 1076 if (spec->field_width < 0) { 1077 spec->field_width = -spec->field_width; 1078 spec->flags |= LEFT; 1079 } 1080 spec->type = FORMAT_TYPE_NONE; 1081 goto precision; 1082 } 1083 1084 /* we finished early by reading the precision */ 1085 if (spec->type == FORMAT_TYPE_PRECISION) { 1086 if (spec->precision < 0) 1087 spec->precision = 0; 1088 1089 spec->type = FORMAT_TYPE_NONE; 1090 goto qualifier; 1091 } 1092 1093 /* By default */ 1094 spec->type = FORMAT_TYPE_NONE; 1095 1096 for (; *fmt ; ++fmt) { 1097 if (*fmt == '%') 1098 break; 1099 } 1100 1101 /* Return the current non-format string */ 1102 if (fmt != start || !*fmt) 1103 return fmt - start; 1104 1105 /* Process flags */ 1106 spec->flags = 0; 1107 1108 while (1) { /* this also skips first '%' */ 1109 bool found = true; 1110 1111 ++fmt; 1112 1113 switch (*fmt) { 1114 case '-': spec->flags |= LEFT; break; 1115 case '+': spec->flags |= PLUS; break; 1116 case ' ': spec->flags |= SPACE; break; 1117 case '#': spec->flags |= SPECIAL; break; 1118 case '0': spec->flags |= ZEROPAD; break; 1119 default: found = false; 1120 } 1121 1122 if (!found) 1123 break; 1124 } 1125 1126 /* get field width */ 1127 spec->field_width = -1; 1128 1129 if (isdigit(*fmt)) 1130 spec->field_width = skip_atoi(&fmt); 1131 else if (*fmt == '*') { 1132 /* it's the next argument */ 1133 spec->type = FORMAT_TYPE_WIDTH; 1134 return ++fmt - start; 1135 } 1136 1137 precision: 1138 /* get the precision */ 1139 spec->precision = -1; 1140 if (*fmt == '.') { 1141 ++fmt; 1142 if (isdigit(*fmt)) { 1143 spec->precision = skip_atoi(&fmt); 1144 if (spec->precision < 0) 1145 spec->precision = 0; 1146 } else if (*fmt == '*') { 1147 /* it's the next argument */ 1148 spec->type = FORMAT_TYPE_PRECISION; 1149 return ++fmt - start; 1150 } 1151 } 1152 1153 qualifier: 1154 /* get the conversion qualifier */ 1155 spec->qualifier = -1; 1156 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1157 TOLOWER(*fmt) == 'z' || *fmt == 't') { 1158 spec->qualifier = *fmt++; 1159 if (unlikely(spec->qualifier == *fmt)) { 1160 if (spec->qualifier == 'l') { 1161 spec->qualifier = 'L'; 1162 ++fmt; 1163 } else if (spec->qualifier == 'h') { 1164 spec->qualifier = 'H'; 1165 ++fmt; 1166 } 1167 } 1168 } 1169 1170 /* default base */ 1171 spec->base = 10; 1172 switch (*fmt) { 1173 case 'c': 1174 spec->type = FORMAT_TYPE_CHAR; 1175 return ++fmt - start; 1176 1177 case 's': 1178 spec->type = FORMAT_TYPE_STR; 1179 return ++fmt - start; 1180 1181 case 'p': 1182 spec->type = FORMAT_TYPE_PTR; 1183 return fmt - start; 1184 /* skip alnum */ 1185 1186 case 'n': 1187 spec->type = FORMAT_TYPE_NRCHARS; 1188 return ++fmt - start; 1189 1190 case '%': 1191 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1192 return ++fmt - start; 1193 1194 /* integer number formats - set up the flags and "break" */ 1195 case 'o': 1196 spec->base = 8; 1197 break; 1198 1199 case 'x': 1200 spec->flags |= SMALL; 1201 1202 case 'X': 1203 spec->base = 16; 1204 break; 1205 1206 case 'd': 1207 case 'i': 1208 spec->flags |= SIGN; 1209 case 'u': 1210 break; 1211 1212 default: 1213 spec->type = FORMAT_TYPE_INVALID; 1214 return fmt - start; 1215 } 1216 1217 if (spec->qualifier == 'L') 1218 spec->type = FORMAT_TYPE_LONG_LONG; 1219 else if (spec->qualifier == 'l') { 1220 if (spec->flags & SIGN) 1221 spec->type = FORMAT_TYPE_LONG; 1222 else 1223 spec->type = FORMAT_TYPE_ULONG; 1224 } else if (TOLOWER(spec->qualifier) == 'z') { 1225 spec->type = FORMAT_TYPE_SIZE_T; 1226 } else if (spec->qualifier == 't') { 1227 spec->type = FORMAT_TYPE_PTRDIFF; 1228 } else if (spec->qualifier == 'H') { 1229 if (spec->flags & SIGN) 1230 spec->type = FORMAT_TYPE_BYTE; 1231 else 1232 spec->type = FORMAT_TYPE_UBYTE; 1233 } else if (spec->qualifier == 'h') { 1234 if (spec->flags & SIGN) 1235 spec->type = FORMAT_TYPE_SHORT; 1236 else 1237 spec->type = FORMAT_TYPE_USHORT; 1238 } else { 1239 if (spec->flags & SIGN) 1240 spec->type = FORMAT_TYPE_INT; 1241 else 1242 spec->type = FORMAT_TYPE_UINT; 1243 } 1244 1245 return ++fmt - start; 1246 } 1247 1248 /** 1249 * vsnprintf - Format a string and place it in a buffer 1250 * @buf: The buffer to place the result into 1251 * @size: The size of the buffer, including the trailing null space 1252 * @fmt: The format string to use 1253 * @args: Arguments for the format string 1254 * 1255 * This function follows C99 vsnprintf, but has some extensions: 1256 * %pS output the name of a text symbol with offset 1257 * %ps output the name of a text symbol without offset 1258 * %pF output the name of a function pointer with its offset 1259 * %pf output the name of a function pointer without its offset 1260 * %pR output the address range in a struct resource with decoded flags 1261 * %pr output the address range in a struct resource with raw flags 1262 * %pM output a 6-byte MAC address with colons 1263 * %pm output a 6-byte MAC address without colons 1264 * %pI4 print an IPv4 address without leading zeros 1265 * %pi4 print an IPv4 address with leading zeros 1266 * %pI6 print an IPv6 address with colons 1267 * %pi6 print an IPv6 address without colons 1268 * %pI6c print an IPv6 address as specified by 1269 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 1270 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1271 * case. 1272 * %n is ignored 1273 * 1274 * The return value is the number of characters which would 1275 * be generated for the given input, excluding the trailing 1276 * '\0', as per ISO C99. If you want to have the exact 1277 * number of characters written into @buf as return value 1278 * (not including the trailing '\0'), use vscnprintf(). If the 1279 * return is greater than or equal to @size, the resulting 1280 * string is truncated. 1281 * 1282 * Call this function if you are already dealing with a va_list. 1283 * You probably want snprintf() instead. 1284 */ 1285 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1286 { 1287 unsigned long long num; 1288 char *str, *end; 1289 struct printf_spec spec = {0}; 1290 1291 /* Reject out-of-range values early. Large positive sizes are 1292 used for unknown buffer sizes. */ 1293 if (WARN_ON_ONCE((int) size < 0)) 1294 return 0; 1295 1296 str = buf; 1297 end = buf + size; 1298 1299 /* Make sure end is always >= buf */ 1300 if (end < buf) { 1301 end = ((void *)-1); 1302 size = end - buf; 1303 } 1304 1305 while (*fmt) { 1306 const char *old_fmt = fmt; 1307 int read = format_decode(fmt, &spec); 1308 1309 fmt += read; 1310 1311 switch (spec.type) { 1312 case FORMAT_TYPE_NONE: { 1313 int copy = read; 1314 if (str < end) { 1315 if (copy > end - str) 1316 copy = end - str; 1317 memcpy(str, old_fmt, copy); 1318 } 1319 str += read; 1320 break; 1321 } 1322 1323 case FORMAT_TYPE_WIDTH: 1324 spec.field_width = va_arg(args, int); 1325 break; 1326 1327 case FORMAT_TYPE_PRECISION: 1328 spec.precision = va_arg(args, int); 1329 break; 1330 1331 case FORMAT_TYPE_CHAR: { 1332 char c; 1333 1334 if (!(spec.flags & LEFT)) { 1335 while (--spec.field_width > 0) { 1336 if (str < end) 1337 *str = ' '; 1338 ++str; 1339 1340 } 1341 } 1342 c = (unsigned char) va_arg(args, int); 1343 if (str < end) 1344 *str = c; 1345 ++str; 1346 while (--spec.field_width > 0) { 1347 if (str < end) 1348 *str = ' '; 1349 ++str; 1350 } 1351 break; 1352 } 1353 1354 case FORMAT_TYPE_STR: 1355 str = string(str, end, va_arg(args, char *), spec); 1356 break; 1357 1358 case FORMAT_TYPE_PTR: 1359 str = pointer(fmt+1, str, end, va_arg(args, void *), 1360 spec); 1361 while (isalnum(*fmt)) 1362 fmt++; 1363 break; 1364 1365 case FORMAT_TYPE_PERCENT_CHAR: 1366 if (str < end) 1367 *str = '%'; 1368 ++str; 1369 break; 1370 1371 case FORMAT_TYPE_INVALID: 1372 if (str < end) 1373 *str = '%'; 1374 ++str; 1375 break; 1376 1377 case FORMAT_TYPE_NRCHARS: { 1378 u8 qualifier = spec.qualifier; 1379 1380 if (qualifier == 'l') { 1381 long *ip = va_arg(args, long *); 1382 *ip = (str - buf); 1383 } else if (TOLOWER(qualifier) == 'z') { 1384 size_t *ip = va_arg(args, size_t *); 1385 *ip = (str - buf); 1386 } else { 1387 int *ip = va_arg(args, int *); 1388 *ip = (str - buf); 1389 } 1390 break; 1391 } 1392 1393 default: 1394 switch (spec.type) { 1395 case FORMAT_TYPE_LONG_LONG: 1396 num = va_arg(args, long long); 1397 break; 1398 case FORMAT_TYPE_ULONG: 1399 num = va_arg(args, unsigned long); 1400 break; 1401 case FORMAT_TYPE_LONG: 1402 num = va_arg(args, long); 1403 break; 1404 case FORMAT_TYPE_SIZE_T: 1405 num = va_arg(args, size_t); 1406 break; 1407 case FORMAT_TYPE_PTRDIFF: 1408 num = va_arg(args, ptrdiff_t); 1409 break; 1410 case FORMAT_TYPE_UBYTE: 1411 num = (unsigned char) va_arg(args, int); 1412 break; 1413 case FORMAT_TYPE_BYTE: 1414 num = (signed char) va_arg(args, int); 1415 break; 1416 case FORMAT_TYPE_USHORT: 1417 num = (unsigned short) va_arg(args, int); 1418 break; 1419 case FORMAT_TYPE_SHORT: 1420 num = (short) va_arg(args, int); 1421 break; 1422 case FORMAT_TYPE_INT: 1423 num = (int) va_arg(args, int); 1424 break; 1425 default: 1426 num = va_arg(args, unsigned int); 1427 } 1428 1429 str = number(str, end, num, spec); 1430 } 1431 } 1432 1433 if (size > 0) { 1434 if (str < end) 1435 *str = '\0'; 1436 else 1437 end[-1] = '\0'; 1438 } 1439 1440 /* the trailing null byte doesn't count towards the total */ 1441 return str-buf; 1442 1443 } 1444 EXPORT_SYMBOL(vsnprintf); 1445 1446 /** 1447 * vscnprintf - Format a string and place it in a buffer 1448 * @buf: The buffer to place the result into 1449 * @size: The size of the buffer, including the trailing null space 1450 * @fmt: The format string to use 1451 * @args: Arguments for the format string 1452 * 1453 * The return value is the number of characters which have been written into 1454 * the @buf not including the trailing '\0'. If @size is <= 0 the function 1455 * returns 0. 1456 * 1457 * Call this function if you are already dealing with a va_list. 1458 * You probably want scnprintf() instead. 1459 * 1460 * See the vsnprintf() documentation for format string extensions over C99. 1461 */ 1462 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1463 { 1464 int i; 1465 1466 i = vsnprintf(buf, size, fmt, args); 1467 1468 return (i >= size) ? (size - 1) : i; 1469 } 1470 EXPORT_SYMBOL(vscnprintf); 1471 1472 /** 1473 * snprintf - Format a string and place it in a buffer 1474 * @buf: The buffer to place the result into 1475 * @size: The size of the buffer, including the trailing null space 1476 * @fmt: The format string to use 1477 * @...: Arguments for the format string 1478 * 1479 * The return value is the number of characters which would be 1480 * generated for the given input, excluding the trailing null, 1481 * as per ISO C99. If the return is greater than or equal to 1482 * @size, the resulting string is truncated. 1483 * 1484 * See the vsnprintf() documentation for format string extensions over C99. 1485 */ 1486 int snprintf(char *buf, size_t size, const char *fmt, ...) 1487 { 1488 va_list args; 1489 int i; 1490 1491 va_start(args, fmt); 1492 i = vsnprintf(buf, size, fmt, args); 1493 va_end(args); 1494 1495 return i; 1496 } 1497 EXPORT_SYMBOL(snprintf); 1498 1499 /** 1500 * scnprintf - Format a string and place it in a buffer 1501 * @buf: The buffer to place the result into 1502 * @size: The size of the buffer, including the trailing null space 1503 * @fmt: The format string to use 1504 * @...: Arguments for the format string 1505 * 1506 * The return value is the number of characters written into @buf not including 1507 * the trailing '\0'. If @size is == 0 the function returns 0. 1508 */ 1509 1510 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1511 { 1512 va_list args; 1513 int i; 1514 1515 va_start(args, fmt); 1516 i = vsnprintf(buf, size, fmt, args); 1517 va_end(args); 1518 1519 if (likely(i < size)) 1520 return i; 1521 if (size != 0) 1522 return size - 1; 1523 return 0; 1524 } 1525 EXPORT_SYMBOL(scnprintf); 1526 1527 /** 1528 * vsprintf - Format a string and place it in a buffer 1529 * @buf: The buffer to place the result into 1530 * @fmt: The format string to use 1531 * @args: Arguments for the format string 1532 * 1533 * The function returns the number of characters written 1534 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1535 * buffer overflows. 1536 * 1537 * Call this function if you are already dealing with a va_list. 1538 * You probably want sprintf() instead. 1539 * 1540 * See the vsnprintf() documentation for format string extensions over C99. 1541 */ 1542 int vsprintf(char *buf, const char *fmt, va_list args) 1543 { 1544 return vsnprintf(buf, INT_MAX, fmt, args); 1545 } 1546 EXPORT_SYMBOL(vsprintf); 1547 1548 /** 1549 * sprintf - Format a string and place it in a buffer 1550 * @buf: The buffer to place the result into 1551 * @fmt: The format string to use 1552 * @...: Arguments for the format string 1553 * 1554 * The function returns the number of characters written 1555 * into @buf. Use snprintf() or scnprintf() in order to avoid 1556 * buffer overflows. 1557 * 1558 * See the vsnprintf() documentation for format string extensions over C99. 1559 */ 1560 int sprintf(char *buf, const char *fmt, ...) 1561 { 1562 va_list args; 1563 int i; 1564 1565 va_start(args, fmt); 1566 i = vsnprintf(buf, INT_MAX, fmt, args); 1567 va_end(args); 1568 1569 return i; 1570 } 1571 EXPORT_SYMBOL(sprintf); 1572 1573 #ifdef CONFIG_BINARY_PRINTF 1574 /* 1575 * bprintf service: 1576 * vbin_printf() - VA arguments to binary data 1577 * bstr_printf() - Binary data to text string 1578 */ 1579 1580 /** 1581 * vbin_printf - Parse a format string and place args' binary value in a buffer 1582 * @bin_buf: The buffer to place args' binary value 1583 * @size: The size of the buffer(by words(32bits), not characters) 1584 * @fmt: The format string to use 1585 * @args: Arguments for the format string 1586 * 1587 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1588 * is skiped. 1589 * 1590 * The return value is the number of words(32bits) which would be generated for 1591 * the given input. 1592 * 1593 * NOTE: 1594 * If the return value is greater than @size, the resulting bin_buf is NOT 1595 * valid for bstr_printf(). 1596 */ 1597 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1598 { 1599 struct printf_spec spec = {0}; 1600 char *str, *end; 1601 1602 str = (char *)bin_buf; 1603 end = (char *)(bin_buf + size); 1604 1605 #define save_arg(type) \ 1606 do { \ 1607 if (sizeof(type) == 8) { \ 1608 unsigned long long value; \ 1609 str = PTR_ALIGN(str, sizeof(u32)); \ 1610 value = va_arg(args, unsigned long long); \ 1611 if (str + sizeof(type) <= end) { \ 1612 *(u32 *)str = *(u32 *)&value; \ 1613 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1614 } \ 1615 } else { \ 1616 unsigned long value; \ 1617 str = PTR_ALIGN(str, sizeof(type)); \ 1618 value = va_arg(args, int); \ 1619 if (str + sizeof(type) <= end) \ 1620 *(typeof(type) *)str = (type)value; \ 1621 } \ 1622 str += sizeof(type); \ 1623 } while (0) 1624 1625 while (*fmt) { 1626 int read = format_decode(fmt, &spec); 1627 1628 fmt += read; 1629 1630 switch (spec.type) { 1631 case FORMAT_TYPE_NONE: 1632 case FORMAT_TYPE_INVALID: 1633 case FORMAT_TYPE_PERCENT_CHAR: 1634 break; 1635 1636 case FORMAT_TYPE_WIDTH: 1637 case FORMAT_TYPE_PRECISION: 1638 save_arg(int); 1639 break; 1640 1641 case FORMAT_TYPE_CHAR: 1642 save_arg(char); 1643 break; 1644 1645 case FORMAT_TYPE_STR: { 1646 const char *save_str = va_arg(args, char *); 1647 size_t len; 1648 1649 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1650 || (unsigned long)save_str < PAGE_SIZE) 1651 save_str = "(null)"; 1652 len = strlen(save_str) + 1; 1653 if (str + len < end) 1654 memcpy(str, save_str, len); 1655 str += len; 1656 break; 1657 } 1658 1659 case FORMAT_TYPE_PTR: 1660 save_arg(void *); 1661 /* skip all alphanumeric pointer suffixes */ 1662 while (isalnum(*fmt)) 1663 fmt++; 1664 break; 1665 1666 case FORMAT_TYPE_NRCHARS: { 1667 /* skip %n 's argument */ 1668 u8 qualifier = spec.qualifier; 1669 void *skip_arg; 1670 if (qualifier == 'l') 1671 skip_arg = va_arg(args, long *); 1672 else if (TOLOWER(qualifier) == 'z') 1673 skip_arg = va_arg(args, size_t *); 1674 else 1675 skip_arg = va_arg(args, int *); 1676 break; 1677 } 1678 1679 default: 1680 switch (spec.type) { 1681 1682 case FORMAT_TYPE_LONG_LONG: 1683 save_arg(long long); 1684 break; 1685 case FORMAT_TYPE_ULONG: 1686 case FORMAT_TYPE_LONG: 1687 save_arg(unsigned long); 1688 break; 1689 case FORMAT_TYPE_SIZE_T: 1690 save_arg(size_t); 1691 break; 1692 case FORMAT_TYPE_PTRDIFF: 1693 save_arg(ptrdiff_t); 1694 break; 1695 case FORMAT_TYPE_UBYTE: 1696 case FORMAT_TYPE_BYTE: 1697 save_arg(char); 1698 break; 1699 case FORMAT_TYPE_USHORT: 1700 case FORMAT_TYPE_SHORT: 1701 save_arg(short); 1702 break; 1703 default: 1704 save_arg(int); 1705 } 1706 } 1707 } 1708 1709 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1710 #undef save_arg 1711 } 1712 EXPORT_SYMBOL_GPL(vbin_printf); 1713 1714 /** 1715 * bstr_printf - Format a string from binary arguments and place it in a buffer 1716 * @buf: The buffer to place the result into 1717 * @size: The size of the buffer, including the trailing null space 1718 * @fmt: The format string to use 1719 * @bin_buf: Binary arguments for the format string 1720 * 1721 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1722 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1723 * a binary buffer that generated by vbin_printf. 1724 * 1725 * The format follows C99 vsnprintf, but has some extensions: 1726 * see vsnprintf comment for details. 1727 * 1728 * The return value is the number of characters which would 1729 * be generated for the given input, excluding the trailing 1730 * '\0', as per ISO C99. If you want to have the exact 1731 * number of characters written into @buf as return value 1732 * (not including the trailing '\0'), use vscnprintf(). If the 1733 * return is greater than or equal to @size, the resulting 1734 * string is truncated. 1735 */ 1736 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1737 { 1738 struct printf_spec spec = {0}; 1739 char *str, *end; 1740 const char *args = (const char *)bin_buf; 1741 1742 if (WARN_ON_ONCE((int) size < 0)) 1743 return 0; 1744 1745 str = buf; 1746 end = buf + size; 1747 1748 #define get_arg(type) \ 1749 ({ \ 1750 typeof(type) value; \ 1751 if (sizeof(type) == 8) { \ 1752 args = PTR_ALIGN(args, sizeof(u32)); \ 1753 *(u32 *)&value = *(u32 *)args; \ 1754 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1755 } else { \ 1756 args = PTR_ALIGN(args, sizeof(type)); \ 1757 value = *(typeof(type) *)args; \ 1758 } \ 1759 args += sizeof(type); \ 1760 value; \ 1761 }) 1762 1763 /* Make sure end is always >= buf */ 1764 if (end < buf) { 1765 end = ((void *)-1); 1766 size = end - buf; 1767 } 1768 1769 while (*fmt) { 1770 const char *old_fmt = fmt; 1771 int read = format_decode(fmt, &spec); 1772 1773 fmt += read; 1774 1775 switch (spec.type) { 1776 case FORMAT_TYPE_NONE: { 1777 int copy = read; 1778 if (str < end) { 1779 if (copy > end - str) 1780 copy = end - str; 1781 memcpy(str, old_fmt, copy); 1782 } 1783 str += read; 1784 break; 1785 } 1786 1787 case FORMAT_TYPE_WIDTH: 1788 spec.field_width = get_arg(int); 1789 break; 1790 1791 case FORMAT_TYPE_PRECISION: 1792 spec.precision = get_arg(int); 1793 break; 1794 1795 case FORMAT_TYPE_CHAR: { 1796 char c; 1797 1798 if (!(spec.flags & LEFT)) { 1799 while (--spec.field_width > 0) { 1800 if (str < end) 1801 *str = ' '; 1802 ++str; 1803 } 1804 } 1805 c = (unsigned char) get_arg(char); 1806 if (str < end) 1807 *str = c; 1808 ++str; 1809 while (--spec.field_width > 0) { 1810 if (str < end) 1811 *str = ' '; 1812 ++str; 1813 } 1814 break; 1815 } 1816 1817 case FORMAT_TYPE_STR: { 1818 const char *str_arg = args; 1819 args += strlen(str_arg) + 1; 1820 str = string(str, end, (char *)str_arg, spec); 1821 break; 1822 } 1823 1824 case FORMAT_TYPE_PTR: 1825 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1826 while (isalnum(*fmt)) 1827 fmt++; 1828 break; 1829 1830 case FORMAT_TYPE_PERCENT_CHAR: 1831 case FORMAT_TYPE_INVALID: 1832 if (str < end) 1833 *str = '%'; 1834 ++str; 1835 break; 1836 1837 case FORMAT_TYPE_NRCHARS: 1838 /* skip */ 1839 break; 1840 1841 default: { 1842 unsigned long long num; 1843 1844 switch (spec.type) { 1845 1846 case FORMAT_TYPE_LONG_LONG: 1847 num = get_arg(long long); 1848 break; 1849 case FORMAT_TYPE_ULONG: 1850 case FORMAT_TYPE_LONG: 1851 num = get_arg(unsigned long); 1852 break; 1853 case FORMAT_TYPE_SIZE_T: 1854 num = get_arg(size_t); 1855 break; 1856 case FORMAT_TYPE_PTRDIFF: 1857 num = get_arg(ptrdiff_t); 1858 break; 1859 case FORMAT_TYPE_UBYTE: 1860 num = get_arg(unsigned char); 1861 break; 1862 case FORMAT_TYPE_BYTE: 1863 num = get_arg(signed char); 1864 break; 1865 case FORMAT_TYPE_USHORT: 1866 num = get_arg(unsigned short); 1867 break; 1868 case FORMAT_TYPE_SHORT: 1869 num = get_arg(short); 1870 break; 1871 case FORMAT_TYPE_UINT: 1872 num = get_arg(unsigned int); 1873 break; 1874 default: 1875 num = get_arg(int); 1876 } 1877 1878 str = number(str, end, num, spec); 1879 } /* default: */ 1880 } /* switch(spec.type) */ 1881 } /* while(*fmt) */ 1882 1883 if (size > 0) { 1884 if (str < end) 1885 *str = '\0'; 1886 else 1887 end[-1] = '\0'; 1888 } 1889 1890 #undef get_arg 1891 1892 /* the trailing null byte doesn't count towards the total */ 1893 return str - buf; 1894 } 1895 EXPORT_SYMBOL_GPL(bstr_printf); 1896 1897 /** 1898 * bprintf - Parse a format string and place args' binary value in a buffer 1899 * @bin_buf: The buffer to place args' binary value 1900 * @size: The size of the buffer(by words(32bits), not characters) 1901 * @fmt: The format string to use 1902 * @...: Arguments for the format string 1903 * 1904 * The function returns the number of words(u32) written 1905 * into @bin_buf. 1906 */ 1907 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1908 { 1909 va_list args; 1910 int ret; 1911 1912 va_start(args, fmt); 1913 ret = vbin_printf(bin_buf, size, fmt, args); 1914 va_end(args); 1915 1916 return ret; 1917 } 1918 EXPORT_SYMBOL_GPL(bprintf); 1919 1920 #endif /* CONFIG_BINARY_PRINTF */ 1921 1922 /** 1923 * vsscanf - Unformat a buffer into a list of arguments 1924 * @buf: input buffer 1925 * @fmt: format of buffer 1926 * @args: arguments 1927 */ 1928 int vsscanf(const char *buf, const char *fmt, va_list args) 1929 { 1930 const char *str = buf; 1931 char *next; 1932 char digit; 1933 int num = 0; 1934 u8 qualifier; 1935 u8 base; 1936 s16 field_width; 1937 bool is_sign; 1938 1939 while (*fmt && *str) { 1940 /* skip any white space in format */ 1941 /* white space in format matchs any amount of 1942 * white space, including none, in the input. 1943 */ 1944 if (isspace(*fmt)) { 1945 fmt = skip_spaces(++fmt); 1946 str = skip_spaces(str); 1947 } 1948 1949 /* anything that is not a conversion must match exactly */ 1950 if (*fmt != '%' && *fmt) { 1951 if (*fmt++ != *str++) 1952 break; 1953 continue; 1954 } 1955 1956 if (!*fmt) 1957 break; 1958 ++fmt; 1959 1960 /* skip this conversion. 1961 * advance both strings to next white space 1962 */ 1963 if (*fmt == '*') { 1964 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1965 fmt++; 1966 while (!isspace(*str) && *str) 1967 str++; 1968 continue; 1969 } 1970 1971 /* get field width */ 1972 field_width = -1; 1973 if (isdigit(*fmt)) 1974 field_width = skip_atoi(&fmt); 1975 1976 /* get conversion qualifier */ 1977 qualifier = -1; 1978 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1979 TOLOWER(*fmt) == 'z') { 1980 qualifier = *fmt++; 1981 if (unlikely(qualifier == *fmt)) { 1982 if (qualifier == 'h') { 1983 qualifier = 'H'; 1984 fmt++; 1985 } else if (qualifier == 'l') { 1986 qualifier = 'L'; 1987 fmt++; 1988 } 1989 } 1990 } 1991 1992 if (!*fmt || !*str) 1993 break; 1994 1995 base = 10; 1996 is_sign = 0; 1997 1998 switch (*fmt++) { 1999 case 'c': 2000 { 2001 char *s = (char *)va_arg(args, char*); 2002 if (field_width == -1) 2003 field_width = 1; 2004 do { 2005 *s++ = *str++; 2006 } while (--field_width > 0 && *str); 2007 num++; 2008 } 2009 continue; 2010 case 's': 2011 { 2012 char *s = (char *)va_arg(args, char *); 2013 if (field_width == -1) 2014 field_width = SHRT_MAX; 2015 /* first, skip leading white space in buffer */ 2016 str = skip_spaces(str); 2017 2018 /* now copy until next white space */ 2019 while (*str && !isspace(*str) && field_width--) 2020 *s++ = *str++; 2021 *s = '\0'; 2022 num++; 2023 } 2024 continue; 2025 case 'n': 2026 /* return number of characters read so far */ 2027 { 2028 int *i = (int *)va_arg(args, int*); 2029 *i = str - buf; 2030 } 2031 continue; 2032 case 'o': 2033 base = 8; 2034 break; 2035 case 'x': 2036 case 'X': 2037 base = 16; 2038 break; 2039 case 'i': 2040 base = 0; 2041 case 'd': 2042 is_sign = 1; 2043 case 'u': 2044 break; 2045 case '%': 2046 /* looking for '%' in str */ 2047 if (*str++ != '%') 2048 return num; 2049 continue; 2050 default: 2051 /* invalid format; stop here */ 2052 return num; 2053 } 2054 2055 /* have some sort of integer conversion. 2056 * first, skip white space in buffer. 2057 */ 2058 str = skip_spaces(str); 2059 2060 digit = *str; 2061 if (is_sign && digit == '-') 2062 digit = *(str + 1); 2063 2064 if (!digit 2065 || (base == 16 && !isxdigit(digit)) 2066 || (base == 10 && !isdigit(digit)) 2067 || (base == 8 && (!isdigit(digit) || digit > '7')) 2068 || (base == 0 && !isdigit(digit))) 2069 break; 2070 2071 switch (qualifier) { 2072 case 'H': /* that's 'hh' in format */ 2073 if (is_sign) { 2074 signed char *s = (signed char *)va_arg(args, signed char *); 2075 *s = (signed char)simple_strtol(str, &next, base); 2076 } else { 2077 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 2078 *s = (unsigned char)simple_strtoul(str, &next, base); 2079 } 2080 break; 2081 case 'h': 2082 if (is_sign) { 2083 short *s = (short *)va_arg(args, short *); 2084 *s = (short)simple_strtol(str, &next, base); 2085 } else { 2086 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 2087 *s = (unsigned short)simple_strtoul(str, &next, base); 2088 } 2089 break; 2090 case 'l': 2091 if (is_sign) { 2092 long *l = (long *)va_arg(args, long *); 2093 *l = simple_strtol(str, &next, base); 2094 } else { 2095 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 2096 *l = simple_strtoul(str, &next, base); 2097 } 2098 break; 2099 case 'L': 2100 if (is_sign) { 2101 long long *l = (long long *)va_arg(args, long long *); 2102 *l = simple_strtoll(str, &next, base); 2103 } else { 2104 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 2105 *l = simple_strtoull(str, &next, base); 2106 } 2107 break; 2108 case 'Z': 2109 case 'z': 2110 { 2111 size_t *s = (size_t *)va_arg(args, size_t *); 2112 *s = (size_t)simple_strtoul(str, &next, base); 2113 } 2114 break; 2115 default: 2116 if (is_sign) { 2117 int *i = (int *)va_arg(args, int *); 2118 *i = (int)simple_strtol(str, &next, base); 2119 } else { 2120 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2121 *i = (unsigned int)simple_strtoul(str, &next, base); 2122 } 2123 break; 2124 } 2125 num++; 2126 2127 if (!next) 2128 break; 2129 str = next; 2130 } 2131 2132 /* 2133 * Now we've come all the way through so either the input string or the 2134 * format ended. In the former case, there can be a %n at the current 2135 * position in the format that needs to be filled. 2136 */ 2137 if (*fmt == '%' && *(fmt + 1) == 'n') { 2138 int *p = (int *)va_arg(args, int *); 2139 *p = str - buf; 2140 } 2141 2142 return num; 2143 } 2144 EXPORT_SYMBOL(vsscanf); 2145 2146 /** 2147 * sscanf - Unformat a buffer into a list of arguments 2148 * @buf: input buffer 2149 * @fmt: formatting of buffer 2150 * @...: resulting arguments 2151 */ 2152 int sscanf(const char *buf, const char *fmt, ...) 2153 { 2154 va_list args; 2155 int i; 2156 2157 va_start(args, fmt); 2158 i = vsscanf(buf, fmt, args); 2159 va_end(args); 2160 2161 return i; 2162 } 2163 EXPORT_SYMBOL(sscanf); 2164