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> /* for KSYM_SYMBOL_LEN */ 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 #include "kstrtox.h" 35 36 /** 37 * simple_strtoull - convert a string to an unsigned long long 38 * @cp: The start of the string 39 * @endp: A pointer to the end of the parsed string will be placed here 40 * @base: The number base to use 41 */ 42 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 43 { 44 unsigned long long result; 45 unsigned int rv; 46 47 cp = _parse_integer_fixup_radix(cp, &base); 48 rv = _parse_integer(cp, base, &result); 49 /* FIXME */ 50 cp += (rv & ~KSTRTOX_OVERFLOW); 51 52 if (endp) 53 *endp = (char *)cp; 54 55 return result; 56 } 57 EXPORT_SYMBOL(simple_strtoull); 58 59 /** 60 * simple_strtoul - convert a string to an unsigned long 61 * @cp: The start of the string 62 * @endp: A pointer to the end of the parsed string will be placed here 63 * @base: The number base to use 64 */ 65 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 66 { 67 return simple_strtoull(cp, endp, base); 68 } 69 EXPORT_SYMBOL(simple_strtoul); 70 71 /** 72 * simple_strtol - convert a string to a signed long 73 * @cp: The start of the string 74 * @endp: A pointer to the end of the parsed string will be placed here 75 * @base: The number base to use 76 */ 77 long simple_strtol(const char *cp, char **endp, unsigned int base) 78 { 79 if (*cp == '-') 80 return -simple_strtoul(cp + 1, endp, base); 81 82 return simple_strtoul(cp, endp, base); 83 } 84 EXPORT_SYMBOL(simple_strtol); 85 86 /** 87 * simple_strtoll - convert a string to a signed long long 88 * @cp: The start of the string 89 * @endp: A pointer to the end of the parsed string will be placed here 90 * @base: The number base to use 91 */ 92 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 93 { 94 if (*cp == '-') 95 return -simple_strtoull(cp + 1, endp, base); 96 97 return simple_strtoull(cp, endp, base); 98 } 99 EXPORT_SYMBOL(simple_strtoll); 100 101 static noinline_for_stack 102 int skip_atoi(const char **s) 103 { 104 int i = 0; 105 106 while (isdigit(**s)) 107 i = i*10 + *((*s)++) - '0'; 108 109 return i; 110 } 111 112 /* Decimal conversion is by far the most typical, and is used 113 * for /proc and /sys data. This directly impacts e.g. top performance 114 * with many processes running. We optimize it for speed 115 * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html> 116 * (with permission from the author, Douglas W. Jones). 117 */ 118 119 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64 120 /* Formats correctly any integer in [0, 999999999] */ 121 static noinline_for_stack 122 char *put_dec_full9(char *buf, unsigned q) 123 { 124 unsigned r; 125 126 /* 127 * Possible ways to approx. divide by 10 128 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit) 129 * (x * 0xcccd) >> 19 x < 81920 (x < 262149 when 64-bit mul) 130 * (x * 0x6667) >> 18 x < 43699 131 * (x * 0x3334) >> 17 x < 16389 132 * (x * 0x199a) >> 16 x < 16389 133 * (x * 0x0ccd) >> 15 x < 16389 134 * (x * 0x0667) >> 14 x < 2739 135 * (x * 0x0334) >> 13 x < 1029 136 * (x * 0x019a) >> 12 x < 1029 137 * (x * 0x00cd) >> 11 x < 1029 shorter code than * 0x67 (on i386) 138 * (x * 0x0067) >> 10 x < 179 139 * (x * 0x0034) >> 9 x < 69 same 140 * (x * 0x001a) >> 8 x < 69 same 141 * (x * 0x000d) >> 7 x < 69 same, shortest code (on i386) 142 * (x * 0x0007) >> 6 x < 19 143 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html> 144 */ 145 r = (q * (uint64_t)0x1999999a) >> 32; 146 *buf++ = (q - 10 * r) + '0'; /* 1 */ 147 q = (r * (uint64_t)0x1999999a) >> 32; 148 *buf++ = (r - 10 * q) + '0'; /* 2 */ 149 r = (q * (uint64_t)0x1999999a) >> 32; 150 *buf++ = (q - 10 * r) + '0'; /* 3 */ 151 q = (r * (uint64_t)0x1999999a) >> 32; 152 *buf++ = (r - 10 * q) + '0'; /* 4 */ 153 r = (q * (uint64_t)0x1999999a) >> 32; 154 *buf++ = (q - 10 * r) + '0'; /* 5 */ 155 /* Now value is under 10000, can avoid 64-bit multiply */ 156 q = (r * 0x199a) >> 16; 157 *buf++ = (r - 10 * q) + '0'; /* 6 */ 158 r = (q * 0xcd) >> 11; 159 *buf++ = (q - 10 * r) + '0'; /* 7 */ 160 q = (r * 0xcd) >> 11; 161 *buf++ = (r - 10 * q) + '0'; /* 8 */ 162 *buf++ = q + '0'; /* 9 */ 163 return buf; 164 } 165 #endif 166 167 /* Similar to above but do not pad with zeros. 168 * Code can be easily arranged to print 9 digits too, but our callers 169 * always call put_dec_full9() instead when the number has 9 decimal digits. 170 */ 171 static noinline_for_stack 172 char *put_dec_trunc8(char *buf, unsigned r) 173 { 174 unsigned q; 175 176 /* Copy of previous function's body with added early returns */ 177 q = (r * (uint64_t)0x1999999a) >> 32; 178 *buf++ = (r - 10 * q) + '0'; /* 2 */ 179 if (q == 0) 180 return buf; 181 r = (q * (uint64_t)0x1999999a) >> 32; 182 *buf++ = (q - 10 * r) + '0'; /* 3 */ 183 if (r == 0) 184 return buf; 185 q = (r * (uint64_t)0x1999999a) >> 32; 186 *buf++ = (r - 10 * q) + '0'; /* 4 */ 187 if (q == 0) 188 return buf; 189 r = (q * (uint64_t)0x1999999a) >> 32; 190 *buf++ = (q - 10 * r) + '0'; /* 5 */ 191 if (r == 0) 192 return buf; 193 q = (r * 0x199a) >> 16; 194 *buf++ = (r - 10 * q) + '0'; /* 6 */ 195 if (q == 0) 196 return buf; 197 r = (q * 0xcd) >> 11; 198 *buf++ = (q - 10 * r) + '0'; /* 7 */ 199 if (r == 0) 200 return buf; 201 q = (r * 0xcd) >> 11; 202 *buf++ = (r - 10 * q) + '0'; /* 8 */ 203 if (q == 0) 204 return buf; 205 *buf++ = q + '0'; /* 9 */ 206 return buf; 207 } 208 209 /* There are two algorithms to print larger numbers. 210 * One is generic: divide by 1000000000 and repeatedly print 211 * groups of (up to) 9 digits. It's conceptually simple, 212 * but requires a (unsigned long long) / 1000000000 division. 213 * 214 * Second algorithm splits 64-bit unsigned long long into 16-bit chunks, 215 * manipulates them cleverly and generates groups of 4 decimal digits. 216 * It so happens that it does NOT require long long division. 217 * 218 * If long is > 32 bits, division of 64-bit values is relatively easy, 219 * and we will use the first algorithm. 220 * If long long is > 64 bits (strange architecture with VERY large long long), 221 * second algorithm can't be used, and we again use the first one. 222 * 223 * Else (if long is 32 bits and long long is 64 bits) we use second one. 224 */ 225 226 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64 227 228 /* First algorithm: generic */ 229 230 static 231 char *put_dec(char *buf, unsigned long long n) 232 { 233 if (n >= 100*1000*1000) { 234 while (n >= 1000*1000*1000) 235 buf = put_dec_full9(buf, do_div(n, 1000*1000*1000)); 236 if (n >= 100*1000*1000) 237 return put_dec_full9(buf, n); 238 } 239 return put_dec_trunc8(buf, n); 240 } 241 242 #else 243 244 /* Second algorithm: valid only for 64-bit long longs */ 245 246 static noinline_for_stack 247 char *put_dec_full4(char *buf, unsigned q) 248 { 249 unsigned r; 250 r = (q * 0xcccd) >> 19; 251 *buf++ = (q - 10 * r) + '0'; 252 q = (r * 0x199a) >> 16; 253 *buf++ = (r - 10 * q) + '0'; 254 r = (q * 0xcd) >> 11; 255 *buf++ = (q - 10 * r) + '0'; 256 *buf++ = r + '0'; 257 return buf; 258 } 259 260 /* Based on code by Douglas W. Jones found at 261 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 262 * (with permission from the author). 263 * Performs no 64-bit division and hence should be fast on 32-bit machines. 264 */ 265 static 266 char *put_dec(char *buf, unsigned long long n) 267 { 268 uint32_t d3, d2, d1, q, h; 269 270 if (n < 100*1000*1000) 271 return put_dec_trunc8(buf, n); 272 273 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 274 h = (n >> 32); 275 d2 = (h ) & 0xffff; 276 d3 = (h >> 16); /* implicit "& 0xffff" */ 277 278 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 279 280 buf = put_dec_full4(buf, q % 10000); 281 q = q / 10000; 282 283 d1 = q + 7671 * d3 + 9496 * d2 + 6 * d1; 284 buf = put_dec_full4(buf, d1 % 10000); 285 q = d1 / 10000; 286 287 d2 = q + 4749 * d3 + 42 * d2; 288 buf = put_dec_full4(buf, d2 % 10000); 289 q = d2 / 10000; 290 291 d3 = q + 281 * d3; 292 if (!d3) 293 goto done; 294 buf = put_dec_full4(buf, d3 % 10000); 295 q = d3 / 10000; 296 if (!q) 297 goto done; 298 buf = put_dec_full4(buf, q); 299 done: 300 while (buf[-1] == '0') 301 --buf; 302 303 return buf; 304 } 305 306 #endif 307 308 /* 309 * Convert passed number to decimal string. 310 * Returns the length of string. On buffer overflow, returns 0. 311 * 312 * If speed is not important, use snprintf(). It's easy to read the code. 313 */ 314 int num_to_str(char *buf, int size, unsigned long long num) 315 { 316 char tmp[sizeof(num) * 3]; 317 int idx, len; 318 319 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 320 if (num <= 9) { 321 tmp[0] = '0' + num; 322 len = 1; 323 } else { 324 len = put_dec(tmp, num) - tmp; 325 } 326 327 if (len > size) 328 return 0; 329 for (idx = 0; idx < len; ++idx) 330 buf[idx] = tmp[len - idx - 1]; 331 return len; 332 } 333 334 #define ZEROPAD 1 /* pad with zero */ 335 #define SIGN 2 /* unsigned/signed long */ 336 #define PLUS 4 /* show plus */ 337 #define SPACE 8 /* space if plus */ 338 #define LEFT 16 /* left justified */ 339 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 340 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 341 342 enum format_type { 343 FORMAT_TYPE_NONE, /* Just a string part */ 344 FORMAT_TYPE_WIDTH, 345 FORMAT_TYPE_PRECISION, 346 FORMAT_TYPE_CHAR, 347 FORMAT_TYPE_STR, 348 FORMAT_TYPE_PTR, 349 FORMAT_TYPE_PERCENT_CHAR, 350 FORMAT_TYPE_INVALID, 351 FORMAT_TYPE_LONG_LONG, 352 FORMAT_TYPE_ULONG, 353 FORMAT_TYPE_LONG, 354 FORMAT_TYPE_UBYTE, 355 FORMAT_TYPE_BYTE, 356 FORMAT_TYPE_USHORT, 357 FORMAT_TYPE_SHORT, 358 FORMAT_TYPE_UINT, 359 FORMAT_TYPE_INT, 360 FORMAT_TYPE_NRCHARS, 361 FORMAT_TYPE_SIZE_T, 362 FORMAT_TYPE_PTRDIFF 363 }; 364 365 struct printf_spec { 366 u8 type; /* format_type enum */ 367 u8 flags; /* flags to number() */ 368 u8 base; /* number base, 8, 10 or 16 only */ 369 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ 370 s16 field_width; /* width of output field */ 371 s16 precision; /* # of digits/chars */ 372 }; 373 374 static noinline_for_stack 375 char *number(char *buf, char *end, unsigned long long num, 376 struct printf_spec spec) 377 { 378 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 379 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 380 381 char tmp[66]; 382 char sign; 383 char locase; 384 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 385 int i; 386 bool is_zero = num == 0LL; 387 388 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 389 * produces same digits or (maybe lowercased) letters */ 390 locase = (spec.flags & SMALL); 391 if (spec.flags & LEFT) 392 spec.flags &= ~ZEROPAD; 393 sign = 0; 394 if (spec.flags & SIGN) { 395 if ((signed long long)num < 0) { 396 sign = '-'; 397 num = -(signed long long)num; 398 spec.field_width--; 399 } else if (spec.flags & PLUS) { 400 sign = '+'; 401 spec.field_width--; 402 } else if (spec.flags & SPACE) { 403 sign = ' '; 404 spec.field_width--; 405 } 406 } 407 if (need_pfx) { 408 if (spec.base == 16) 409 spec.field_width -= 2; 410 else if (!is_zero) 411 spec.field_width--; 412 } 413 414 /* generate full string in tmp[], in reverse order */ 415 i = 0; 416 if (num < spec.base) 417 tmp[i++] = digits[num] | locase; 418 /* Generic code, for any base: 419 else do { 420 tmp[i++] = (digits[do_div(num,base)] | locase); 421 } while (num != 0); 422 */ 423 else if (spec.base != 10) { /* 8 or 16 */ 424 int mask = spec.base - 1; 425 int shift = 3; 426 427 if (spec.base == 16) 428 shift = 4; 429 do { 430 tmp[i++] = (digits[((unsigned char)num) & mask] | locase); 431 num >>= shift; 432 } while (num); 433 } else { /* base 10 */ 434 i = put_dec(tmp, num) - tmp; 435 } 436 437 /* printing 100 using %2d gives "100", not "00" */ 438 if (i > spec.precision) 439 spec.precision = i; 440 /* leading space padding */ 441 spec.field_width -= spec.precision; 442 if (!(spec.flags & (ZEROPAD+LEFT))) { 443 while (--spec.field_width >= 0) { 444 if (buf < end) 445 *buf = ' '; 446 ++buf; 447 } 448 } 449 /* sign */ 450 if (sign) { 451 if (buf < end) 452 *buf = sign; 453 ++buf; 454 } 455 /* "0x" / "0" prefix */ 456 if (need_pfx) { 457 if (spec.base == 16 || !is_zero) { 458 if (buf < end) 459 *buf = '0'; 460 ++buf; 461 } 462 if (spec.base == 16) { 463 if (buf < end) 464 *buf = ('X' | locase); 465 ++buf; 466 } 467 } 468 /* zero or space padding */ 469 if (!(spec.flags & LEFT)) { 470 char c = (spec.flags & ZEROPAD) ? '0' : ' '; 471 while (--spec.field_width >= 0) { 472 if (buf < end) 473 *buf = c; 474 ++buf; 475 } 476 } 477 /* hmm even more zero padding? */ 478 while (i <= --spec.precision) { 479 if (buf < end) 480 *buf = '0'; 481 ++buf; 482 } 483 /* actual digits of result */ 484 while (--i >= 0) { 485 if (buf < end) 486 *buf = tmp[i]; 487 ++buf; 488 } 489 /* trailing space padding */ 490 while (--spec.field_width >= 0) { 491 if (buf < end) 492 *buf = ' '; 493 ++buf; 494 } 495 496 return buf; 497 } 498 499 static noinline_for_stack 500 char *string(char *buf, char *end, const char *s, struct printf_spec spec) 501 { 502 int len, i; 503 504 if ((unsigned long)s < PAGE_SIZE) 505 s = "(null)"; 506 507 len = strnlen(s, spec.precision); 508 509 if (!(spec.flags & LEFT)) { 510 while (len < spec.field_width--) { 511 if (buf < end) 512 *buf = ' '; 513 ++buf; 514 } 515 } 516 for (i = 0; i < len; ++i) { 517 if (buf < end) 518 *buf = *s; 519 ++buf; ++s; 520 } 521 while (len < spec.field_width--) { 522 if (buf < end) 523 *buf = ' '; 524 ++buf; 525 } 526 527 return buf; 528 } 529 530 static noinline_for_stack 531 char *symbol_string(char *buf, char *end, void *ptr, 532 struct printf_spec spec, char ext) 533 { 534 unsigned long value = (unsigned long) ptr; 535 #ifdef CONFIG_KALLSYMS 536 char sym[KSYM_SYMBOL_LEN]; 537 if (ext == 'B') 538 sprint_backtrace(sym, value); 539 else if (ext != 'f' && ext != 's') 540 sprint_symbol(sym, value); 541 else 542 sprint_symbol_no_offset(sym, value); 543 544 return string(buf, end, sym, spec); 545 #else 546 spec.field_width = 2 * sizeof(void *); 547 spec.flags |= SPECIAL | SMALL | ZEROPAD; 548 spec.base = 16; 549 550 return number(buf, end, value, spec); 551 #endif 552 } 553 554 static noinline_for_stack 555 char *resource_string(char *buf, char *end, struct resource *res, 556 struct printf_spec spec, const char *fmt) 557 { 558 #ifndef IO_RSRC_PRINTK_SIZE 559 #define IO_RSRC_PRINTK_SIZE 6 560 #endif 561 562 #ifndef MEM_RSRC_PRINTK_SIZE 563 #define MEM_RSRC_PRINTK_SIZE 10 564 #endif 565 static const struct printf_spec io_spec = { 566 .base = 16, 567 .field_width = IO_RSRC_PRINTK_SIZE, 568 .precision = -1, 569 .flags = SPECIAL | SMALL | ZEROPAD, 570 }; 571 static const struct printf_spec mem_spec = { 572 .base = 16, 573 .field_width = MEM_RSRC_PRINTK_SIZE, 574 .precision = -1, 575 .flags = SPECIAL | SMALL | ZEROPAD, 576 }; 577 static const struct printf_spec bus_spec = { 578 .base = 16, 579 .field_width = 2, 580 .precision = -1, 581 .flags = SMALL | ZEROPAD, 582 }; 583 static const struct printf_spec dec_spec = { 584 .base = 10, 585 .precision = -1, 586 .flags = 0, 587 }; 588 static const struct printf_spec str_spec = { 589 .field_width = -1, 590 .precision = 10, 591 .flags = LEFT, 592 }; 593 static const struct printf_spec flag_spec = { 594 .base = 16, 595 .precision = -1, 596 .flags = SPECIAL | SMALL, 597 }; 598 599 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 600 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 601 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 602 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 603 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 604 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 605 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 606 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 607 608 char *p = sym, *pend = sym + sizeof(sym); 609 int decode = (fmt[0] == 'R') ? 1 : 0; 610 const struct printf_spec *specp; 611 612 *p++ = '['; 613 if (res->flags & IORESOURCE_IO) { 614 p = string(p, pend, "io ", str_spec); 615 specp = &io_spec; 616 } else if (res->flags & IORESOURCE_MEM) { 617 p = string(p, pend, "mem ", str_spec); 618 specp = &mem_spec; 619 } else if (res->flags & IORESOURCE_IRQ) { 620 p = string(p, pend, "irq ", str_spec); 621 specp = &dec_spec; 622 } else if (res->flags & IORESOURCE_DMA) { 623 p = string(p, pend, "dma ", str_spec); 624 specp = &dec_spec; 625 } else if (res->flags & IORESOURCE_BUS) { 626 p = string(p, pend, "bus ", str_spec); 627 specp = &bus_spec; 628 } else { 629 p = string(p, pend, "??? ", str_spec); 630 specp = &mem_spec; 631 decode = 0; 632 } 633 p = number(p, pend, res->start, *specp); 634 if (res->start != res->end) { 635 *p++ = '-'; 636 p = number(p, pend, res->end, *specp); 637 } 638 if (decode) { 639 if (res->flags & IORESOURCE_MEM_64) 640 p = string(p, pend, " 64bit", str_spec); 641 if (res->flags & IORESOURCE_PREFETCH) 642 p = string(p, pend, " pref", str_spec); 643 if (res->flags & IORESOURCE_WINDOW) 644 p = string(p, pend, " window", str_spec); 645 if (res->flags & IORESOURCE_DISABLED) 646 p = string(p, pend, " disabled", str_spec); 647 } else { 648 p = string(p, pend, " flags ", str_spec); 649 p = number(p, pend, res->flags, flag_spec); 650 } 651 *p++ = ']'; 652 *p = '\0'; 653 654 return string(buf, end, sym, spec); 655 } 656 657 static noinline_for_stack 658 char *mac_address_string(char *buf, char *end, u8 *addr, 659 struct printf_spec spec, const char *fmt) 660 { 661 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 662 char *p = mac_addr; 663 int i; 664 char separator; 665 666 if (fmt[1] == 'F') { /* FDDI canonical format */ 667 separator = '-'; 668 } else { 669 separator = ':'; 670 } 671 672 for (i = 0; i < 6; i++) { 673 p = hex_byte_pack(p, addr[i]); 674 if (fmt[0] == 'M' && i != 5) 675 *p++ = separator; 676 } 677 *p = '\0'; 678 679 return string(buf, end, mac_addr, spec); 680 } 681 682 static noinline_for_stack 683 char *ip4_string(char *p, const u8 *addr, const char *fmt) 684 { 685 int i; 686 bool leading_zeros = (fmt[0] == 'i'); 687 int index; 688 int step; 689 690 switch (fmt[2]) { 691 case 'h': 692 #ifdef __BIG_ENDIAN 693 index = 0; 694 step = 1; 695 #else 696 index = 3; 697 step = -1; 698 #endif 699 break; 700 case 'l': 701 index = 3; 702 step = -1; 703 break; 704 case 'n': 705 case 'b': 706 default: 707 index = 0; 708 step = 1; 709 break; 710 } 711 for (i = 0; i < 4; i++) { 712 char temp[3]; /* hold each IP quad in reverse order */ 713 int digits = put_dec_trunc8(temp, addr[index]) - temp; 714 if (leading_zeros) { 715 if (digits < 3) 716 *p++ = '0'; 717 if (digits < 2) 718 *p++ = '0'; 719 } 720 /* reverse the digits in the quad */ 721 while (digits--) 722 *p++ = temp[digits]; 723 if (i < 3) 724 *p++ = '.'; 725 index += step; 726 } 727 *p = '\0'; 728 729 return p; 730 } 731 732 static noinline_for_stack 733 char *ip6_compressed_string(char *p, const char *addr) 734 { 735 int i, j, range; 736 unsigned char zerolength[8]; 737 int longest = 1; 738 int colonpos = -1; 739 u16 word; 740 u8 hi, lo; 741 bool needcolon = false; 742 bool useIPv4; 743 struct in6_addr in6; 744 745 memcpy(&in6, addr, sizeof(struct in6_addr)); 746 747 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 748 749 memset(zerolength, 0, sizeof(zerolength)); 750 751 if (useIPv4) 752 range = 6; 753 else 754 range = 8; 755 756 /* find position of longest 0 run */ 757 for (i = 0; i < range; i++) { 758 for (j = i; j < range; j++) { 759 if (in6.s6_addr16[j] != 0) 760 break; 761 zerolength[i]++; 762 } 763 } 764 for (i = 0; i < range; i++) { 765 if (zerolength[i] > longest) { 766 longest = zerolength[i]; 767 colonpos = i; 768 } 769 } 770 if (longest == 1) /* don't compress a single 0 */ 771 colonpos = -1; 772 773 /* emit address */ 774 for (i = 0; i < range; i++) { 775 if (i == colonpos) { 776 if (needcolon || i == 0) 777 *p++ = ':'; 778 *p++ = ':'; 779 needcolon = false; 780 i += longest - 1; 781 continue; 782 } 783 if (needcolon) { 784 *p++ = ':'; 785 needcolon = false; 786 } 787 /* hex u16 without leading 0s */ 788 word = ntohs(in6.s6_addr16[i]); 789 hi = word >> 8; 790 lo = word & 0xff; 791 if (hi) { 792 if (hi > 0x0f) 793 p = hex_byte_pack(p, hi); 794 else 795 *p++ = hex_asc_lo(hi); 796 p = hex_byte_pack(p, lo); 797 } 798 else if (lo > 0x0f) 799 p = hex_byte_pack(p, lo); 800 else 801 *p++ = hex_asc_lo(lo); 802 needcolon = true; 803 } 804 805 if (useIPv4) { 806 if (needcolon) 807 *p++ = ':'; 808 p = ip4_string(p, &in6.s6_addr[12], "I4"); 809 } 810 *p = '\0'; 811 812 return p; 813 } 814 815 static noinline_for_stack 816 char *ip6_string(char *p, const char *addr, const char *fmt) 817 { 818 int i; 819 820 for (i = 0; i < 8; i++) { 821 p = hex_byte_pack(p, *addr++); 822 p = hex_byte_pack(p, *addr++); 823 if (fmt[0] == 'I' && i != 7) 824 *p++ = ':'; 825 } 826 *p = '\0'; 827 828 return p; 829 } 830 831 static noinline_for_stack 832 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 833 struct printf_spec spec, const char *fmt) 834 { 835 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 836 837 if (fmt[0] == 'I' && fmt[2] == 'c') 838 ip6_compressed_string(ip6_addr, addr); 839 else 840 ip6_string(ip6_addr, addr, fmt); 841 842 return string(buf, end, ip6_addr, spec); 843 } 844 845 static noinline_for_stack 846 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 847 struct printf_spec spec, const char *fmt) 848 { 849 char ip4_addr[sizeof("255.255.255.255")]; 850 851 ip4_string(ip4_addr, addr, fmt); 852 853 return string(buf, end, ip4_addr, spec); 854 } 855 856 static noinline_for_stack 857 char *uuid_string(char *buf, char *end, const u8 *addr, 858 struct printf_spec spec, const char *fmt) 859 { 860 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 861 char *p = uuid; 862 int i; 863 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 864 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 865 const u8 *index = be; 866 bool uc = false; 867 868 switch (*(++fmt)) { 869 case 'L': 870 uc = true; /* fall-through */ 871 case 'l': 872 index = le; 873 break; 874 case 'B': 875 uc = true; 876 break; 877 } 878 879 for (i = 0; i < 16; i++) { 880 p = hex_byte_pack(p, addr[index[i]]); 881 switch (i) { 882 case 3: 883 case 5: 884 case 7: 885 case 9: 886 *p++ = '-'; 887 break; 888 } 889 } 890 891 *p = 0; 892 893 if (uc) { 894 p = uuid; 895 do { 896 *p = toupper(*p); 897 } while (*(++p)); 898 } 899 900 return string(buf, end, uuid, spec); 901 } 902 903 static 904 char *netdev_feature_string(char *buf, char *end, const u8 *addr, 905 struct printf_spec spec) 906 { 907 spec.flags |= SPECIAL | SMALL | ZEROPAD; 908 if (spec.field_width == -1) 909 spec.field_width = 2 + 2 * sizeof(netdev_features_t); 910 spec.base = 16; 911 912 return number(buf, end, *(const netdev_features_t *)addr, spec); 913 } 914 915 int kptr_restrict __read_mostly; 916 917 /* 918 * Show a '%p' thing. A kernel extension is that the '%p' is followed 919 * by an extra set of alphanumeric characters that are extended format 920 * specifiers. 921 * 922 * Right now we handle: 923 * 924 * - 'F' For symbolic function descriptor pointers with offset 925 * - 'f' For simple symbolic function names without offset 926 * - 'S' For symbolic direct pointers with offset 927 * - 's' For symbolic direct pointers without offset 928 * - 'B' For backtraced symbolic direct pointers with offset 929 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 930 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 931 * - 'M' For a 6-byte MAC address, it prints the address in the 932 * usual colon-separated hex notation 933 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 934 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 935 * with a dash-separated hex notation 936 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 937 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 938 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 939 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 940 * IPv6 omits the colons (01020304...0f) 941 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 942 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 943 * - 'I6c' for IPv6 addresses printed as specified by 944 * http://tools.ietf.org/html/rfc5952 945 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 946 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 947 * Options for %pU are: 948 * b big endian lower case hex (default) 949 * B big endian UPPER case hex 950 * l little endian lower case hex 951 * L little endian UPPER case hex 952 * big endian output byte order is: 953 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 954 * little endian output byte order is: 955 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 956 * - 'V' For a struct va_format which contains a format string * and va_list *, 957 * call vsnprintf(->format, *->va_list). 958 * Implements a "recursive vsnprintf". 959 * Do not use this feature without some mechanism to verify the 960 * correctness of the format string and va_list arguments. 961 * - 'K' For a kernel pointer that should be hidden from unprivileged users 962 * - 'NF' For a netdev_features_t 963 * 964 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 965 * function pointers are really function descriptors, which contain a 966 * pointer to the real address. 967 */ 968 static noinline_for_stack 969 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 970 struct printf_spec spec) 971 { 972 int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0); 973 974 if (!ptr && *fmt != 'K') { 975 /* 976 * Print (null) with the same width as a pointer so it makes 977 * tabular output look nice. 978 */ 979 if (spec.field_width == -1) 980 spec.field_width = default_width; 981 return string(buf, end, "(null)", spec); 982 } 983 984 switch (*fmt) { 985 case 'F': 986 case 'f': 987 ptr = dereference_function_descriptor(ptr); 988 /* Fallthrough */ 989 case 'S': 990 case 's': 991 case 'B': 992 return symbol_string(buf, end, ptr, spec, *fmt); 993 case 'R': 994 case 'r': 995 return resource_string(buf, end, ptr, spec, fmt); 996 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 997 case 'm': /* Contiguous: 000102030405 */ 998 /* [mM]F (FDDI, bit reversed) */ 999 return mac_address_string(buf, end, ptr, spec, fmt); 1000 case 'I': /* Formatted IP supported 1001 * 4: 1.2.3.4 1002 * 6: 0001:0203:...:0708 1003 * 6c: 1::708 or 1::1.2.3.4 1004 */ 1005 case 'i': /* Contiguous: 1006 * 4: 001.002.003.004 1007 * 6: 000102...0f 1008 */ 1009 switch (fmt[1]) { 1010 case '6': 1011 return ip6_addr_string(buf, end, ptr, spec, fmt); 1012 case '4': 1013 return ip4_addr_string(buf, end, ptr, spec, fmt); 1014 } 1015 break; 1016 case 'U': 1017 return uuid_string(buf, end, ptr, spec, fmt); 1018 case 'V': 1019 { 1020 va_list va; 1021 1022 va_copy(va, *((struct va_format *)ptr)->va); 1023 buf += vsnprintf(buf, end > buf ? end - buf : 0, 1024 ((struct va_format *)ptr)->fmt, va); 1025 va_end(va); 1026 return buf; 1027 } 1028 case 'K': 1029 /* 1030 * %pK cannot be used in IRQ context because its test 1031 * for CAP_SYSLOG would be meaningless. 1032 */ 1033 if (in_irq() || in_serving_softirq() || in_nmi()) { 1034 if (spec.field_width == -1) 1035 spec.field_width = default_width; 1036 return string(buf, end, "pK-error", spec); 1037 } 1038 if (!((kptr_restrict == 0) || 1039 (kptr_restrict == 1 && 1040 has_capability_noaudit(current, CAP_SYSLOG)))) 1041 ptr = NULL; 1042 break; 1043 case 'N': 1044 switch (fmt[1]) { 1045 case 'F': 1046 return netdev_feature_string(buf, end, ptr, spec); 1047 } 1048 break; 1049 } 1050 spec.flags |= SMALL; 1051 if (spec.field_width == -1) { 1052 spec.field_width = default_width; 1053 spec.flags |= ZEROPAD; 1054 } 1055 spec.base = 16; 1056 1057 return number(buf, end, (unsigned long) ptr, spec); 1058 } 1059 1060 /* 1061 * Helper function to decode printf style format. 1062 * Each call decode a token from the format and return the 1063 * number of characters read (or likely the delta where it wants 1064 * to go on the next call). 1065 * The decoded token is returned through the parameters 1066 * 1067 * 'h', 'l', or 'L' for integer fields 1068 * 'z' support added 23/7/1999 S.H. 1069 * 'z' changed to 'Z' --davidm 1/25/99 1070 * 't' added for ptrdiff_t 1071 * 1072 * @fmt: the format string 1073 * @type of the token returned 1074 * @flags: various flags such as +, -, # tokens.. 1075 * @field_width: overwritten width 1076 * @base: base of the number (octal, hex, ...) 1077 * @precision: precision of a number 1078 * @qualifier: qualifier of a number (long, size_t, ...) 1079 */ 1080 static noinline_for_stack 1081 int format_decode(const char *fmt, struct printf_spec *spec) 1082 { 1083 const char *start = fmt; 1084 1085 /* we finished early by reading the field width */ 1086 if (spec->type == FORMAT_TYPE_WIDTH) { 1087 if (spec->field_width < 0) { 1088 spec->field_width = -spec->field_width; 1089 spec->flags |= LEFT; 1090 } 1091 spec->type = FORMAT_TYPE_NONE; 1092 goto precision; 1093 } 1094 1095 /* we finished early by reading the precision */ 1096 if (spec->type == FORMAT_TYPE_PRECISION) { 1097 if (spec->precision < 0) 1098 spec->precision = 0; 1099 1100 spec->type = FORMAT_TYPE_NONE; 1101 goto qualifier; 1102 } 1103 1104 /* By default */ 1105 spec->type = FORMAT_TYPE_NONE; 1106 1107 for (; *fmt ; ++fmt) { 1108 if (*fmt == '%') 1109 break; 1110 } 1111 1112 /* Return the current non-format string */ 1113 if (fmt != start || !*fmt) 1114 return fmt - start; 1115 1116 /* Process flags */ 1117 spec->flags = 0; 1118 1119 while (1) { /* this also skips first '%' */ 1120 bool found = true; 1121 1122 ++fmt; 1123 1124 switch (*fmt) { 1125 case '-': spec->flags |= LEFT; break; 1126 case '+': spec->flags |= PLUS; break; 1127 case ' ': spec->flags |= SPACE; break; 1128 case '#': spec->flags |= SPECIAL; break; 1129 case '0': spec->flags |= ZEROPAD; break; 1130 default: found = false; 1131 } 1132 1133 if (!found) 1134 break; 1135 } 1136 1137 /* get field width */ 1138 spec->field_width = -1; 1139 1140 if (isdigit(*fmt)) 1141 spec->field_width = skip_atoi(&fmt); 1142 else if (*fmt == '*') { 1143 /* it's the next argument */ 1144 spec->type = FORMAT_TYPE_WIDTH; 1145 return ++fmt - start; 1146 } 1147 1148 precision: 1149 /* get the precision */ 1150 spec->precision = -1; 1151 if (*fmt == '.') { 1152 ++fmt; 1153 if (isdigit(*fmt)) { 1154 spec->precision = skip_atoi(&fmt); 1155 if (spec->precision < 0) 1156 spec->precision = 0; 1157 } else if (*fmt == '*') { 1158 /* it's the next argument */ 1159 spec->type = FORMAT_TYPE_PRECISION; 1160 return ++fmt - start; 1161 } 1162 } 1163 1164 qualifier: 1165 /* get the conversion qualifier */ 1166 spec->qualifier = -1; 1167 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 1168 _tolower(*fmt) == 'z' || *fmt == 't') { 1169 spec->qualifier = *fmt++; 1170 if (unlikely(spec->qualifier == *fmt)) { 1171 if (spec->qualifier == 'l') { 1172 spec->qualifier = 'L'; 1173 ++fmt; 1174 } else if (spec->qualifier == 'h') { 1175 spec->qualifier = 'H'; 1176 ++fmt; 1177 } 1178 } 1179 } 1180 1181 /* default base */ 1182 spec->base = 10; 1183 switch (*fmt) { 1184 case 'c': 1185 spec->type = FORMAT_TYPE_CHAR; 1186 return ++fmt - start; 1187 1188 case 's': 1189 spec->type = FORMAT_TYPE_STR; 1190 return ++fmt - start; 1191 1192 case 'p': 1193 spec->type = FORMAT_TYPE_PTR; 1194 return fmt - start; 1195 /* skip alnum */ 1196 1197 case 'n': 1198 spec->type = FORMAT_TYPE_NRCHARS; 1199 return ++fmt - start; 1200 1201 case '%': 1202 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1203 return ++fmt - start; 1204 1205 /* integer number formats - set up the flags and "break" */ 1206 case 'o': 1207 spec->base = 8; 1208 break; 1209 1210 case 'x': 1211 spec->flags |= SMALL; 1212 1213 case 'X': 1214 spec->base = 16; 1215 break; 1216 1217 case 'd': 1218 case 'i': 1219 spec->flags |= SIGN; 1220 case 'u': 1221 break; 1222 1223 default: 1224 spec->type = FORMAT_TYPE_INVALID; 1225 return fmt - start; 1226 } 1227 1228 if (spec->qualifier == 'L') 1229 spec->type = FORMAT_TYPE_LONG_LONG; 1230 else if (spec->qualifier == 'l') { 1231 if (spec->flags & SIGN) 1232 spec->type = FORMAT_TYPE_LONG; 1233 else 1234 spec->type = FORMAT_TYPE_ULONG; 1235 } else if (_tolower(spec->qualifier) == 'z') { 1236 spec->type = FORMAT_TYPE_SIZE_T; 1237 } else if (spec->qualifier == 't') { 1238 spec->type = FORMAT_TYPE_PTRDIFF; 1239 } else if (spec->qualifier == 'H') { 1240 if (spec->flags & SIGN) 1241 spec->type = FORMAT_TYPE_BYTE; 1242 else 1243 spec->type = FORMAT_TYPE_UBYTE; 1244 } else if (spec->qualifier == 'h') { 1245 if (spec->flags & SIGN) 1246 spec->type = FORMAT_TYPE_SHORT; 1247 else 1248 spec->type = FORMAT_TYPE_USHORT; 1249 } else { 1250 if (spec->flags & SIGN) 1251 spec->type = FORMAT_TYPE_INT; 1252 else 1253 spec->type = FORMAT_TYPE_UINT; 1254 } 1255 1256 return ++fmt - start; 1257 } 1258 1259 /** 1260 * vsnprintf - Format a string and place it in a buffer 1261 * @buf: The buffer to place the result into 1262 * @size: The size of the buffer, including the trailing null space 1263 * @fmt: The format string to use 1264 * @args: Arguments for the format string 1265 * 1266 * This function follows C99 vsnprintf, but has some extensions: 1267 * %pS output the name of a text symbol with offset 1268 * %ps output the name of a text symbol without offset 1269 * %pF output the name of a function pointer with its offset 1270 * %pf output the name of a function pointer without its offset 1271 * %pB output the name of a backtrace symbol with its offset 1272 * %pR output the address range in a struct resource with decoded flags 1273 * %pr output the address range in a struct resource with raw flags 1274 * %pM output a 6-byte MAC address with colons 1275 * %pm output a 6-byte MAC address without colons 1276 * %pI4 print an IPv4 address without leading zeros 1277 * %pi4 print an IPv4 address with leading zeros 1278 * %pI6 print an IPv6 address with colons 1279 * %pi6 print an IPv6 address without colons 1280 * %pI6c print an IPv6 address as specified by RFC 5952 1281 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1282 * case. 1283 * %n is ignored 1284 * 1285 * The return value is the number of characters which would 1286 * be generated for the given input, excluding the trailing 1287 * '\0', as per ISO C99. If you want to have the exact 1288 * number of characters written into @buf as return value 1289 * (not including the trailing '\0'), use vscnprintf(). If the 1290 * return is greater than or equal to @size, the resulting 1291 * string is truncated. 1292 * 1293 * If you're not already dealing with a va_list consider using snprintf(). 1294 */ 1295 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1296 { 1297 unsigned long long num; 1298 char *str, *end; 1299 struct printf_spec spec = {0}; 1300 1301 /* Reject out-of-range values early. Large positive sizes are 1302 used for unknown buffer sizes. */ 1303 if (WARN_ON_ONCE((int) size < 0)) 1304 return 0; 1305 1306 str = buf; 1307 end = buf + size; 1308 1309 /* Make sure end is always >= buf */ 1310 if (end < buf) { 1311 end = ((void *)-1); 1312 size = end - buf; 1313 } 1314 1315 while (*fmt) { 1316 const char *old_fmt = fmt; 1317 int read = format_decode(fmt, &spec); 1318 1319 fmt += read; 1320 1321 switch (spec.type) { 1322 case FORMAT_TYPE_NONE: { 1323 int copy = read; 1324 if (str < end) { 1325 if (copy > end - str) 1326 copy = end - str; 1327 memcpy(str, old_fmt, copy); 1328 } 1329 str += read; 1330 break; 1331 } 1332 1333 case FORMAT_TYPE_WIDTH: 1334 spec.field_width = va_arg(args, int); 1335 break; 1336 1337 case FORMAT_TYPE_PRECISION: 1338 spec.precision = va_arg(args, int); 1339 break; 1340 1341 case FORMAT_TYPE_CHAR: { 1342 char c; 1343 1344 if (!(spec.flags & LEFT)) { 1345 while (--spec.field_width > 0) { 1346 if (str < end) 1347 *str = ' '; 1348 ++str; 1349 1350 } 1351 } 1352 c = (unsigned char) va_arg(args, int); 1353 if (str < end) 1354 *str = c; 1355 ++str; 1356 while (--spec.field_width > 0) { 1357 if (str < end) 1358 *str = ' '; 1359 ++str; 1360 } 1361 break; 1362 } 1363 1364 case FORMAT_TYPE_STR: 1365 str = string(str, end, va_arg(args, char *), spec); 1366 break; 1367 1368 case FORMAT_TYPE_PTR: 1369 str = pointer(fmt+1, str, end, va_arg(args, void *), 1370 spec); 1371 while (isalnum(*fmt)) 1372 fmt++; 1373 break; 1374 1375 case FORMAT_TYPE_PERCENT_CHAR: 1376 if (str < end) 1377 *str = '%'; 1378 ++str; 1379 break; 1380 1381 case FORMAT_TYPE_INVALID: 1382 if (str < end) 1383 *str = '%'; 1384 ++str; 1385 break; 1386 1387 case FORMAT_TYPE_NRCHARS: { 1388 u8 qualifier = spec.qualifier; 1389 1390 if (qualifier == 'l') { 1391 long *ip = va_arg(args, long *); 1392 *ip = (str - buf); 1393 } else if (_tolower(qualifier) == 'z') { 1394 size_t *ip = va_arg(args, size_t *); 1395 *ip = (str - buf); 1396 } else { 1397 int *ip = va_arg(args, int *); 1398 *ip = (str - buf); 1399 } 1400 break; 1401 } 1402 1403 default: 1404 switch (spec.type) { 1405 case FORMAT_TYPE_LONG_LONG: 1406 num = va_arg(args, long long); 1407 break; 1408 case FORMAT_TYPE_ULONG: 1409 num = va_arg(args, unsigned long); 1410 break; 1411 case FORMAT_TYPE_LONG: 1412 num = va_arg(args, long); 1413 break; 1414 case FORMAT_TYPE_SIZE_T: 1415 num = va_arg(args, size_t); 1416 break; 1417 case FORMAT_TYPE_PTRDIFF: 1418 num = va_arg(args, ptrdiff_t); 1419 break; 1420 case FORMAT_TYPE_UBYTE: 1421 num = (unsigned char) va_arg(args, int); 1422 break; 1423 case FORMAT_TYPE_BYTE: 1424 num = (signed char) va_arg(args, int); 1425 break; 1426 case FORMAT_TYPE_USHORT: 1427 num = (unsigned short) va_arg(args, int); 1428 break; 1429 case FORMAT_TYPE_SHORT: 1430 num = (short) va_arg(args, int); 1431 break; 1432 case FORMAT_TYPE_INT: 1433 num = (int) va_arg(args, int); 1434 break; 1435 default: 1436 num = va_arg(args, unsigned int); 1437 } 1438 1439 str = number(str, end, num, spec); 1440 } 1441 } 1442 1443 if (size > 0) { 1444 if (str < end) 1445 *str = '\0'; 1446 else 1447 end[-1] = '\0'; 1448 } 1449 1450 /* the trailing null byte doesn't count towards the total */ 1451 return str-buf; 1452 1453 } 1454 EXPORT_SYMBOL(vsnprintf); 1455 1456 /** 1457 * vscnprintf - Format a string and place it in a buffer 1458 * @buf: The buffer to place the result into 1459 * @size: The size of the buffer, including the trailing null space 1460 * @fmt: The format string to use 1461 * @args: Arguments for the format string 1462 * 1463 * The return value is the number of characters which have been written into 1464 * the @buf not including the trailing '\0'. If @size is == 0 the function 1465 * returns 0. 1466 * 1467 * If you're not already dealing with a va_list consider using scnprintf(). 1468 * 1469 * See the vsnprintf() documentation for format string extensions over C99. 1470 */ 1471 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1472 { 1473 int i; 1474 1475 i = vsnprintf(buf, size, fmt, args); 1476 1477 if (likely(i < size)) 1478 return i; 1479 if (size != 0) 1480 return size - 1; 1481 return 0; 1482 } 1483 EXPORT_SYMBOL(vscnprintf); 1484 1485 /** 1486 * snprintf - Format a string and place it in a buffer 1487 * @buf: The buffer to place the result into 1488 * @size: The size of the buffer, including the trailing null space 1489 * @fmt: The format string to use 1490 * @...: Arguments for the format string 1491 * 1492 * The return value is the number of characters which would be 1493 * generated for the given input, excluding the trailing null, 1494 * as per ISO C99. If the return is greater than or equal to 1495 * @size, the resulting string is truncated. 1496 * 1497 * See the vsnprintf() documentation for format string extensions over C99. 1498 */ 1499 int snprintf(char *buf, size_t size, const char *fmt, ...) 1500 { 1501 va_list args; 1502 int i; 1503 1504 va_start(args, fmt); 1505 i = vsnprintf(buf, size, fmt, args); 1506 va_end(args); 1507 1508 return i; 1509 } 1510 EXPORT_SYMBOL(snprintf); 1511 1512 /** 1513 * scnprintf - Format a string and place it in a buffer 1514 * @buf: The buffer to place the result into 1515 * @size: The size of the buffer, including the trailing null space 1516 * @fmt: The format string to use 1517 * @...: Arguments for the format string 1518 * 1519 * The return value is the number of characters written into @buf not including 1520 * the trailing '\0'. If @size is == 0 the function returns 0. 1521 */ 1522 1523 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1524 { 1525 va_list args; 1526 int i; 1527 1528 va_start(args, fmt); 1529 i = vscnprintf(buf, size, fmt, args); 1530 va_end(args); 1531 1532 return i; 1533 } 1534 EXPORT_SYMBOL(scnprintf); 1535 1536 /** 1537 * vsprintf - Format a string and place it in a buffer 1538 * @buf: The buffer to place the result into 1539 * @fmt: The format string to use 1540 * @args: Arguments for the format string 1541 * 1542 * The function returns the number of characters written 1543 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1544 * buffer overflows. 1545 * 1546 * If you're not already dealing with a va_list consider using sprintf(). 1547 * 1548 * See the vsnprintf() documentation for format string extensions over C99. 1549 */ 1550 int vsprintf(char *buf, const char *fmt, va_list args) 1551 { 1552 return vsnprintf(buf, INT_MAX, fmt, args); 1553 } 1554 EXPORT_SYMBOL(vsprintf); 1555 1556 /** 1557 * sprintf - Format a string and place it in a buffer 1558 * @buf: The buffer to place the result into 1559 * @fmt: The format string to use 1560 * @...: Arguments for the format string 1561 * 1562 * The function returns the number of characters written 1563 * into @buf. Use snprintf() or scnprintf() in order to avoid 1564 * buffer overflows. 1565 * 1566 * See the vsnprintf() documentation for format string extensions over C99. 1567 */ 1568 int sprintf(char *buf, const char *fmt, ...) 1569 { 1570 va_list args; 1571 int i; 1572 1573 va_start(args, fmt); 1574 i = vsnprintf(buf, INT_MAX, fmt, args); 1575 va_end(args); 1576 1577 return i; 1578 } 1579 EXPORT_SYMBOL(sprintf); 1580 1581 #ifdef CONFIG_BINARY_PRINTF 1582 /* 1583 * bprintf service: 1584 * vbin_printf() - VA arguments to binary data 1585 * bstr_printf() - Binary data to text string 1586 */ 1587 1588 /** 1589 * vbin_printf - Parse a format string and place args' binary value in a buffer 1590 * @bin_buf: The buffer to place args' binary value 1591 * @size: The size of the buffer(by words(32bits), not characters) 1592 * @fmt: The format string to use 1593 * @args: Arguments for the format string 1594 * 1595 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1596 * is skiped. 1597 * 1598 * The return value is the number of words(32bits) which would be generated for 1599 * the given input. 1600 * 1601 * NOTE: 1602 * If the return value is greater than @size, the resulting bin_buf is NOT 1603 * valid for bstr_printf(). 1604 */ 1605 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1606 { 1607 struct printf_spec spec = {0}; 1608 char *str, *end; 1609 1610 str = (char *)bin_buf; 1611 end = (char *)(bin_buf + size); 1612 1613 #define save_arg(type) \ 1614 do { \ 1615 if (sizeof(type) == 8) { \ 1616 unsigned long long value; \ 1617 str = PTR_ALIGN(str, sizeof(u32)); \ 1618 value = va_arg(args, unsigned long long); \ 1619 if (str + sizeof(type) <= end) { \ 1620 *(u32 *)str = *(u32 *)&value; \ 1621 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1622 } \ 1623 } else { \ 1624 unsigned long value; \ 1625 str = PTR_ALIGN(str, sizeof(type)); \ 1626 value = va_arg(args, int); \ 1627 if (str + sizeof(type) <= end) \ 1628 *(typeof(type) *)str = (type)value; \ 1629 } \ 1630 str += sizeof(type); \ 1631 } while (0) 1632 1633 while (*fmt) { 1634 int read = format_decode(fmt, &spec); 1635 1636 fmt += read; 1637 1638 switch (spec.type) { 1639 case FORMAT_TYPE_NONE: 1640 case FORMAT_TYPE_INVALID: 1641 case FORMAT_TYPE_PERCENT_CHAR: 1642 break; 1643 1644 case FORMAT_TYPE_WIDTH: 1645 case FORMAT_TYPE_PRECISION: 1646 save_arg(int); 1647 break; 1648 1649 case FORMAT_TYPE_CHAR: 1650 save_arg(char); 1651 break; 1652 1653 case FORMAT_TYPE_STR: { 1654 const char *save_str = va_arg(args, char *); 1655 size_t len; 1656 1657 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1658 || (unsigned long)save_str < PAGE_SIZE) 1659 save_str = "(null)"; 1660 len = strlen(save_str) + 1; 1661 if (str + len < end) 1662 memcpy(str, save_str, len); 1663 str += len; 1664 break; 1665 } 1666 1667 case FORMAT_TYPE_PTR: 1668 save_arg(void *); 1669 /* skip all alphanumeric pointer suffixes */ 1670 while (isalnum(*fmt)) 1671 fmt++; 1672 break; 1673 1674 case FORMAT_TYPE_NRCHARS: { 1675 /* skip %n 's argument */ 1676 u8 qualifier = spec.qualifier; 1677 void *skip_arg; 1678 if (qualifier == 'l') 1679 skip_arg = va_arg(args, long *); 1680 else if (_tolower(qualifier) == 'z') 1681 skip_arg = va_arg(args, size_t *); 1682 else 1683 skip_arg = va_arg(args, int *); 1684 break; 1685 } 1686 1687 default: 1688 switch (spec.type) { 1689 1690 case FORMAT_TYPE_LONG_LONG: 1691 save_arg(long long); 1692 break; 1693 case FORMAT_TYPE_ULONG: 1694 case FORMAT_TYPE_LONG: 1695 save_arg(unsigned long); 1696 break; 1697 case FORMAT_TYPE_SIZE_T: 1698 save_arg(size_t); 1699 break; 1700 case FORMAT_TYPE_PTRDIFF: 1701 save_arg(ptrdiff_t); 1702 break; 1703 case FORMAT_TYPE_UBYTE: 1704 case FORMAT_TYPE_BYTE: 1705 save_arg(char); 1706 break; 1707 case FORMAT_TYPE_USHORT: 1708 case FORMAT_TYPE_SHORT: 1709 save_arg(short); 1710 break; 1711 default: 1712 save_arg(int); 1713 } 1714 } 1715 } 1716 1717 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1718 #undef save_arg 1719 } 1720 EXPORT_SYMBOL_GPL(vbin_printf); 1721 1722 /** 1723 * bstr_printf - Format a string from binary arguments and place it in a buffer 1724 * @buf: The buffer to place the result into 1725 * @size: The size of the buffer, including the trailing null space 1726 * @fmt: The format string to use 1727 * @bin_buf: Binary arguments for the format string 1728 * 1729 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1730 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1731 * a binary buffer that generated by vbin_printf. 1732 * 1733 * The format follows C99 vsnprintf, but has some extensions: 1734 * see vsnprintf comment for details. 1735 * 1736 * The return value is the number of characters which would 1737 * be generated for the given input, excluding the trailing 1738 * '\0', as per ISO C99. If you want to have the exact 1739 * number of characters written into @buf as return value 1740 * (not including the trailing '\0'), use vscnprintf(). If the 1741 * return is greater than or equal to @size, the resulting 1742 * string is truncated. 1743 */ 1744 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1745 { 1746 struct printf_spec spec = {0}; 1747 char *str, *end; 1748 const char *args = (const char *)bin_buf; 1749 1750 if (WARN_ON_ONCE((int) size < 0)) 1751 return 0; 1752 1753 str = buf; 1754 end = buf + size; 1755 1756 #define get_arg(type) \ 1757 ({ \ 1758 typeof(type) value; \ 1759 if (sizeof(type) == 8) { \ 1760 args = PTR_ALIGN(args, sizeof(u32)); \ 1761 *(u32 *)&value = *(u32 *)args; \ 1762 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1763 } else { \ 1764 args = PTR_ALIGN(args, sizeof(type)); \ 1765 value = *(typeof(type) *)args; \ 1766 } \ 1767 args += sizeof(type); \ 1768 value; \ 1769 }) 1770 1771 /* Make sure end is always >= buf */ 1772 if (end < buf) { 1773 end = ((void *)-1); 1774 size = end - buf; 1775 } 1776 1777 while (*fmt) { 1778 const char *old_fmt = fmt; 1779 int read = format_decode(fmt, &spec); 1780 1781 fmt += read; 1782 1783 switch (spec.type) { 1784 case FORMAT_TYPE_NONE: { 1785 int copy = read; 1786 if (str < end) { 1787 if (copy > end - str) 1788 copy = end - str; 1789 memcpy(str, old_fmt, copy); 1790 } 1791 str += read; 1792 break; 1793 } 1794 1795 case FORMAT_TYPE_WIDTH: 1796 spec.field_width = get_arg(int); 1797 break; 1798 1799 case FORMAT_TYPE_PRECISION: 1800 spec.precision = get_arg(int); 1801 break; 1802 1803 case FORMAT_TYPE_CHAR: { 1804 char c; 1805 1806 if (!(spec.flags & LEFT)) { 1807 while (--spec.field_width > 0) { 1808 if (str < end) 1809 *str = ' '; 1810 ++str; 1811 } 1812 } 1813 c = (unsigned char) get_arg(char); 1814 if (str < end) 1815 *str = c; 1816 ++str; 1817 while (--spec.field_width > 0) { 1818 if (str < end) 1819 *str = ' '; 1820 ++str; 1821 } 1822 break; 1823 } 1824 1825 case FORMAT_TYPE_STR: { 1826 const char *str_arg = args; 1827 args += strlen(str_arg) + 1; 1828 str = string(str, end, (char *)str_arg, spec); 1829 break; 1830 } 1831 1832 case FORMAT_TYPE_PTR: 1833 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1834 while (isalnum(*fmt)) 1835 fmt++; 1836 break; 1837 1838 case FORMAT_TYPE_PERCENT_CHAR: 1839 case FORMAT_TYPE_INVALID: 1840 if (str < end) 1841 *str = '%'; 1842 ++str; 1843 break; 1844 1845 case FORMAT_TYPE_NRCHARS: 1846 /* skip */ 1847 break; 1848 1849 default: { 1850 unsigned long long num; 1851 1852 switch (spec.type) { 1853 1854 case FORMAT_TYPE_LONG_LONG: 1855 num = get_arg(long long); 1856 break; 1857 case FORMAT_TYPE_ULONG: 1858 case FORMAT_TYPE_LONG: 1859 num = get_arg(unsigned long); 1860 break; 1861 case FORMAT_TYPE_SIZE_T: 1862 num = get_arg(size_t); 1863 break; 1864 case FORMAT_TYPE_PTRDIFF: 1865 num = get_arg(ptrdiff_t); 1866 break; 1867 case FORMAT_TYPE_UBYTE: 1868 num = get_arg(unsigned char); 1869 break; 1870 case FORMAT_TYPE_BYTE: 1871 num = get_arg(signed char); 1872 break; 1873 case FORMAT_TYPE_USHORT: 1874 num = get_arg(unsigned short); 1875 break; 1876 case FORMAT_TYPE_SHORT: 1877 num = get_arg(short); 1878 break; 1879 case FORMAT_TYPE_UINT: 1880 num = get_arg(unsigned int); 1881 break; 1882 default: 1883 num = get_arg(int); 1884 } 1885 1886 str = number(str, end, num, spec); 1887 } /* default: */ 1888 } /* switch(spec.type) */ 1889 } /* while(*fmt) */ 1890 1891 if (size > 0) { 1892 if (str < end) 1893 *str = '\0'; 1894 else 1895 end[-1] = '\0'; 1896 } 1897 1898 #undef get_arg 1899 1900 /* the trailing null byte doesn't count towards the total */ 1901 return str - buf; 1902 } 1903 EXPORT_SYMBOL_GPL(bstr_printf); 1904 1905 /** 1906 * bprintf - Parse a format string and place args' binary value in a buffer 1907 * @bin_buf: The buffer to place args' binary value 1908 * @size: The size of the buffer(by words(32bits), not characters) 1909 * @fmt: The format string to use 1910 * @...: Arguments for the format string 1911 * 1912 * The function returns the number of words(u32) written 1913 * into @bin_buf. 1914 */ 1915 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1916 { 1917 va_list args; 1918 int ret; 1919 1920 va_start(args, fmt); 1921 ret = vbin_printf(bin_buf, size, fmt, args); 1922 va_end(args); 1923 1924 return ret; 1925 } 1926 EXPORT_SYMBOL_GPL(bprintf); 1927 1928 #endif /* CONFIG_BINARY_PRINTF */ 1929 1930 /** 1931 * vsscanf - Unformat a buffer into a list of arguments 1932 * @buf: input buffer 1933 * @fmt: format of buffer 1934 * @args: arguments 1935 */ 1936 int vsscanf(const char *buf, const char *fmt, va_list args) 1937 { 1938 const char *str = buf; 1939 char *next; 1940 char digit; 1941 int num = 0; 1942 u8 qualifier; 1943 u8 base; 1944 s16 field_width; 1945 bool is_sign; 1946 1947 while (*fmt && *str) { 1948 /* skip any white space in format */ 1949 /* white space in format matchs any amount of 1950 * white space, including none, in the input. 1951 */ 1952 if (isspace(*fmt)) { 1953 fmt = skip_spaces(++fmt); 1954 str = skip_spaces(str); 1955 } 1956 1957 /* anything that is not a conversion must match exactly */ 1958 if (*fmt != '%' && *fmt) { 1959 if (*fmt++ != *str++) 1960 break; 1961 continue; 1962 } 1963 1964 if (!*fmt) 1965 break; 1966 ++fmt; 1967 1968 /* skip this conversion. 1969 * advance both strings to next white space 1970 */ 1971 if (*fmt == '*') { 1972 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1973 fmt++; 1974 while (!isspace(*str) && *str) 1975 str++; 1976 continue; 1977 } 1978 1979 /* get field width */ 1980 field_width = -1; 1981 if (isdigit(*fmt)) 1982 field_width = skip_atoi(&fmt); 1983 1984 /* get conversion qualifier */ 1985 qualifier = -1; 1986 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 1987 _tolower(*fmt) == 'z') { 1988 qualifier = *fmt++; 1989 if (unlikely(qualifier == *fmt)) { 1990 if (qualifier == 'h') { 1991 qualifier = 'H'; 1992 fmt++; 1993 } else if (qualifier == 'l') { 1994 qualifier = 'L'; 1995 fmt++; 1996 } 1997 } 1998 } 1999 2000 if (!*fmt || !*str) 2001 break; 2002 2003 base = 10; 2004 is_sign = 0; 2005 2006 switch (*fmt++) { 2007 case 'c': 2008 { 2009 char *s = (char *)va_arg(args, char*); 2010 if (field_width == -1) 2011 field_width = 1; 2012 do { 2013 *s++ = *str++; 2014 } while (--field_width > 0 && *str); 2015 num++; 2016 } 2017 continue; 2018 case 's': 2019 { 2020 char *s = (char *)va_arg(args, char *); 2021 if (field_width == -1) 2022 field_width = SHRT_MAX; 2023 /* first, skip leading white space in buffer */ 2024 str = skip_spaces(str); 2025 2026 /* now copy until next white space */ 2027 while (*str && !isspace(*str) && field_width--) 2028 *s++ = *str++; 2029 *s = '\0'; 2030 num++; 2031 } 2032 continue; 2033 case 'n': 2034 /* return number of characters read so far */ 2035 { 2036 int *i = (int *)va_arg(args, int*); 2037 *i = str - buf; 2038 } 2039 continue; 2040 case 'o': 2041 base = 8; 2042 break; 2043 case 'x': 2044 case 'X': 2045 base = 16; 2046 break; 2047 case 'i': 2048 base = 0; 2049 case 'd': 2050 is_sign = 1; 2051 case 'u': 2052 break; 2053 case '%': 2054 /* looking for '%' in str */ 2055 if (*str++ != '%') 2056 return num; 2057 continue; 2058 default: 2059 /* invalid format; stop here */ 2060 return num; 2061 } 2062 2063 /* have some sort of integer conversion. 2064 * first, skip white space in buffer. 2065 */ 2066 str = skip_spaces(str); 2067 2068 digit = *str; 2069 if (is_sign && digit == '-') 2070 digit = *(str + 1); 2071 2072 if (!digit 2073 || (base == 16 && !isxdigit(digit)) 2074 || (base == 10 && !isdigit(digit)) 2075 || (base == 8 && (!isdigit(digit) || digit > '7')) 2076 || (base == 0 && !isdigit(digit))) 2077 break; 2078 2079 switch (qualifier) { 2080 case 'H': /* that's 'hh' in format */ 2081 if (is_sign) { 2082 signed char *s = (signed char *)va_arg(args, signed char *); 2083 *s = (signed char)simple_strtol(str, &next, base); 2084 } else { 2085 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 2086 *s = (unsigned char)simple_strtoul(str, &next, base); 2087 } 2088 break; 2089 case 'h': 2090 if (is_sign) { 2091 short *s = (short *)va_arg(args, short *); 2092 *s = (short)simple_strtol(str, &next, base); 2093 } else { 2094 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 2095 *s = (unsigned short)simple_strtoul(str, &next, base); 2096 } 2097 break; 2098 case 'l': 2099 if (is_sign) { 2100 long *l = (long *)va_arg(args, long *); 2101 *l = simple_strtol(str, &next, base); 2102 } else { 2103 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 2104 *l = simple_strtoul(str, &next, base); 2105 } 2106 break; 2107 case 'L': 2108 if (is_sign) { 2109 long long *l = (long long *)va_arg(args, long long *); 2110 *l = simple_strtoll(str, &next, base); 2111 } else { 2112 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 2113 *l = simple_strtoull(str, &next, base); 2114 } 2115 break; 2116 case 'Z': 2117 case 'z': 2118 { 2119 size_t *s = (size_t *)va_arg(args, size_t *); 2120 *s = (size_t)simple_strtoul(str, &next, base); 2121 } 2122 break; 2123 default: 2124 if (is_sign) { 2125 int *i = (int *)va_arg(args, int *); 2126 *i = (int)simple_strtol(str, &next, base); 2127 } else { 2128 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2129 *i = (unsigned int)simple_strtoul(str, &next, base); 2130 } 2131 break; 2132 } 2133 num++; 2134 2135 if (!next) 2136 break; 2137 str = next; 2138 } 2139 2140 /* 2141 * Now we've come all the way through so either the input string or the 2142 * format ended. In the former case, there can be a %n at the current 2143 * position in the format that needs to be filled. 2144 */ 2145 if (*fmt == '%' && *(fmt + 1) == 'n') { 2146 int *p = (int *)va_arg(args, int *); 2147 *p = str - buf; 2148 } 2149 2150 return num; 2151 } 2152 EXPORT_SYMBOL(vsscanf); 2153 2154 /** 2155 * sscanf - Unformat a buffer into a list of arguments 2156 * @buf: input buffer 2157 * @fmt: formatting of buffer 2158 * @...: resulting arguments 2159 */ 2160 int sscanf(const char *buf, const char *fmt, ...) 2161 { 2162 va_list args; 2163 int i; 2164 2165 va_start(args, fmt); 2166 i = vsscanf(buf, fmt, args); 2167 va_end(args); 2168 2169 return i; 2170 } 2171 EXPORT_SYMBOL(sscanf); 2172