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