/* * linux/lib/vsprintf.c * * Copyright (C) 1991, 1992 Linus Torvalds */ /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ /* * Wirzenius wrote this portably, Torvalds fucked it up :-) */ /* * Fri Jul 13 2001 Crutcher Dunnavant * - changed to provide snprintf and vsnprintf functions * So Feb 1 16:51:32 CET 2004 Juergen Quade * - scnprintf and vscnprintf */ #include #include #include #include #include #include #include #include #include #include struct va_format { const char *fmt; va_list *va; }; #ifndef dereference_function_descriptor #define dereference_function_descriptor(p) (p) #endif const char hex_asc[] = "0123456789abcdef"; /* Works only for digits and letters, but small and fast */ #define TOLOWER(x) ((x) | 0x20) static unsigned int simple_guess_base(const char *cp) { if (cp[0] == '0') { if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2])) return 16; else return 8; } else { return 10; } } /** * simple_strtoull - convert a string to an unsigned long long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) { unsigned long long result = 0; if (!base) base = simple_guess_base(cp); if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x') cp += 2; while (isxdigit(*cp)) { unsigned int value; value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10; if (value >= base) break; result = result * base + value; cp++; } if (endp) *endp = (char *)cp; return result; } EXPORT_SYMBOL(simple_strtoull); /** * simple_strtoul - convert a string to an unsigned long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) { return simple_strtoull(cp, endp, base); } EXPORT_SYMBOL(simple_strtoul); /** * simple_strtol - convert a string to a signed long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ long simple_strtol(const char *cp, char **endp, unsigned int base) { if (*cp == '-') return -simple_strtoul(cp + 1, endp, base); return simple_strtoul(cp, endp, base); } EXPORT_SYMBOL(simple_strtol); /** * simple_strtoll - convert a string to a signed long long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ long long simple_strtoll(const char *cp, char **endp, unsigned int base) { if (*cp == '-') return -simple_strtoull(cp + 1, endp, base); return simple_strtoull(cp, endp, base); } EXPORT_SYMBOL(simple_strtoll); /** * strict_strtoul - convert a string to an unsigned long strictly * @cp: The string to be converted * @base: The number base to use * @res: The converted result value * * strict_strtoul converts a string to an unsigned long only if the * string is really an unsigned long string, any string containing * any invalid char at the tail will be rejected and -EINVAL is returned, * only a newline char at the tail is acceptible because people generally * change a module parameter in the following way: * * echo 1024 > /sys/module/e1000/parameters/copybreak * * echo will append a newline to the tail. * * It returns 0 if conversion is successful and *res is set to the converted * value, otherwise it returns -EINVAL and *res is set to 0. * * simple_strtoul just ignores the successive invalid characters and * return the converted value of prefix part of the string. */ int strict_strtoul(const char *cp, unsigned int base, unsigned long *res) { char *tail; unsigned long val; *res = 0; if (!*cp) return -EINVAL; val = simple_strtoul(cp, &tail, base); if (tail == cp) return -EINVAL; if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) { *res = val; return 0; } return -EINVAL; } EXPORT_SYMBOL(strict_strtoul); /** * strict_strtol - convert a string to a long strictly * @cp: The string to be converted * @base: The number base to use * @res: The converted result value * * strict_strtol is similiar to strict_strtoul, but it allows the first * character of a string is '-'. * * It returns 0 if conversion is successful and *res is set to the converted * value, otherwise it returns -EINVAL and *res is set to 0. */ int strict_strtol(const char *cp, unsigned int base, long *res) { int ret; if (*cp == '-') { ret = strict_strtoul(cp + 1, base, (unsigned long *)res); if (!ret) *res = -(*res); } else { ret = strict_strtoul(cp, base, (unsigned long *)res); } return ret; } EXPORT_SYMBOL(strict_strtol); /** * strict_strtoull - convert a string to an unsigned long long strictly * @cp: The string to be converted * @base: The number base to use * @res: The converted result value * * strict_strtoull converts a string to an unsigned long long only if the * string is really an unsigned long long string, any string containing * any invalid char at the tail will be rejected and -EINVAL is returned, * only a newline char at the tail is acceptible because people generally * change a module parameter in the following way: * * echo 1024 > /sys/module/e1000/parameters/copybreak * * echo will append a newline to the tail of the string. * * It returns 0 if conversion is successful and *res is set to the converted * value, otherwise it returns -EINVAL and *res is set to 0. * * simple_strtoull just ignores the successive invalid characters and * return the converted value of prefix part of the string. */ int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res) { char *tail; unsigned long long val; *res = 0; if (!*cp) return -EINVAL; val = simple_strtoull(cp, &tail, base); if (tail == cp) return -EINVAL; if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) { *res = val; return 0; } return -EINVAL; } EXPORT_SYMBOL(strict_strtoull); /** * strict_strtoll - convert a string to a long long strictly * @cp: The string to be converted * @base: The number base to use * @res: The converted result value * * strict_strtoll is similiar to strict_strtoull, but it allows the first * character of a string is '-'. * * It returns 0 if conversion is successful and *res is set to the converted * value, otherwise it returns -EINVAL and *res is set to 0. */ int strict_strtoll(const char *cp, unsigned int base, long long *res) { int ret; if (*cp == '-') { ret = strict_strtoull(cp + 1, base, (unsigned long long *)res); if (!ret) *res = -(*res); } else { ret = strict_strtoull(cp, base, (unsigned long long *)res); } return ret; } EXPORT_SYMBOL(strict_strtoll); static noinline_for_stack int skip_atoi(const char **s) { int i = 0; while (isdigit(**s)) i = i*10 + *((*s)++) - '0'; return i; } /* Decimal conversion is by far the most typical, and is used * for /proc and /sys data. This directly impacts e.g. top performance * with many processes running. We optimize it for speed * using code from * http://www.cs.uiowa.edu/~jones/bcd/decimal.html * (with permission from the author, Douglas W. Jones). */ /* Formats correctly any integer in [0,99999]. * Outputs from one to five digits depending on input. * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ static noinline_for_stack char *put_dec_trunc(char *buf, unsigned q) { unsigned d3, d2, d1, d0; d1 = (q>>4) & 0xf; d2 = (q>>8) & 0xf; d3 = (q>>12); d0 = 6*(d3 + d2 + d1) + (q & 0xf); q = (d0 * 0xcd) >> 11; d0 = d0 - 10*q; *buf++ = d0 + '0'; /* least significant digit */ d1 = q + 9*d3 + 5*d2 + d1; if (d1 != 0) { q = (d1 * 0xcd) >> 11; d1 = d1 - 10*q; *buf++ = d1 + '0'; /* next digit */ d2 = q + 2*d2; if ((d2 != 0) || (d3 != 0)) { q = (d2 * 0xd) >> 7; d2 = d2 - 10*q; *buf++ = d2 + '0'; /* next digit */ d3 = q + 4*d3; if (d3 != 0) { q = (d3 * 0xcd) >> 11; d3 = d3 - 10*q; *buf++ = d3 + '0'; /* next digit */ if (q != 0) *buf++ = q + '0'; /* most sign. digit */ } } } return buf; } /* Same with if's removed. Always emits five digits */ static noinline_for_stack char *put_dec_full(char *buf, unsigned q) { /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ /* but anyway, gcc produces better code with full-sized ints */ unsigned d3, d2, d1, d0; d1 = (q>>4) & 0xf; d2 = (q>>8) & 0xf; d3 = (q>>12); /* * Possible ways to approx. divide by 10 * gcc -O2 replaces multiply with shifts and adds * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) * (x * 0x67) >> 10: 1100111 * (x * 0x34) >> 9: 110100 - same * (x * 0x1a) >> 8: 11010 - same * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) */ d0 = 6*(d3 + d2 + d1) + (q & 0xf); q = (d0 * 0xcd) >> 11; d0 = d0 - 10*q; *buf++ = d0 + '0'; d1 = q + 9*d3 + 5*d2 + d1; q = (d1 * 0xcd) >> 11; d1 = d1 - 10*q; *buf++ = d1 + '0'; d2 = q + 2*d2; q = (d2 * 0xd) >> 7; d2 = d2 - 10*q; *buf++ = d2 + '0'; d3 = q + 4*d3; q = (d3 * 0xcd) >> 11; /* - shorter code */ /* q = (d3 * 0x67) >> 10; - would also work */ d3 = d3 - 10*q; *buf++ = d3 + '0'; *buf++ = q + '0'; return buf; } /* No inlining helps gcc to use registers better */ static noinline_for_stack char *put_dec(char *buf, unsigned long long num) { while (1) { unsigned rem; if (num < 100000) return put_dec_trunc(buf, num); rem = do_div(num, 100000); buf = put_dec_full(buf, rem); } } #define ZEROPAD 1 /* pad with zero */ #define SIGN 2 /* unsigned/signed long */ #define PLUS 4 /* show plus */ #define SPACE 8 /* space if plus */ #define LEFT 16 /* left justified */ #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ enum format_type { FORMAT_TYPE_NONE, /* Just a string part */ FORMAT_TYPE_WIDTH, FORMAT_TYPE_PRECISION, FORMAT_TYPE_CHAR, FORMAT_TYPE_STR, FORMAT_TYPE_PTR, FORMAT_TYPE_PERCENT_CHAR, FORMAT_TYPE_INVALID, FORMAT_TYPE_LONG_LONG, FORMAT_TYPE_ULONG, FORMAT_TYPE_LONG, FORMAT_TYPE_UBYTE, FORMAT_TYPE_BYTE, FORMAT_TYPE_USHORT, FORMAT_TYPE_SHORT, FORMAT_TYPE_UINT, FORMAT_TYPE_INT, FORMAT_TYPE_NRCHARS, FORMAT_TYPE_SIZE_T, FORMAT_TYPE_PTRDIFF }; struct printf_spec { u8 type; /* format_type enum */ u8 flags; /* flags to number() */ u8 base; /* number base, 8, 10 or 16 only */ u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ s16 field_width; /* width of output field */ s16 precision; /* # of digits/chars */ }; static noinline_for_stack char *number(char *buf, char *end, unsigned long long num, struct printf_spec spec) { /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ char tmp[66]; char sign; char locase; int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); int i; /* locase = 0 or 0x20. ORing digits or letters with 'locase' * produces same digits or (maybe lowercased) letters */ locase = (spec.flags & SMALL); if (spec.flags & LEFT) spec.flags &= ~ZEROPAD; sign = 0; if (spec.flags & SIGN) { if ((signed long long)num < 0) { sign = '-'; num = -(signed long long)num; spec.field_width--; } else if (spec.flags & PLUS) { sign = '+'; spec.field_width--; } else if (spec.flags & SPACE) { sign = ' '; spec.field_width--; } } if (need_pfx) { spec.field_width--; if (spec.base == 16) spec.field_width--; } /* generate full string in tmp[], in reverse order */ i = 0; if (num == 0) tmp[i++] = '0'; /* Generic code, for any base: else do { tmp[i++] = (digits[do_div(num,base)] | locase); } while (num != 0); */ else if (spec.base != 10) { /* 8 or 16 */ int mask = spec.base - 1; int shift = 3; if (spec.base == 16) shift = 4; do { tmp[i++] = (digits[((unsigned char)num) & mask] | locase); num >>= shift; } while (num); } else { /* base 10 */ i = put_dec(tmp, num) - tmp; } /* printing 100 using %2d gives "100", not "00" */ if (i > spec.precision) spec.precision = i; /* leading space padding */ spec.field_width -= spec.precision; if (!(spec.flags & (ZEROPAD+LEFT))) { while (--spec.field_width >= 0) { if (buf < end) *buf = ' '; ++buf; } } /* sign */ if (sign) { if (buf < end) *buf = sign; ++buf; } /* "0x" / "0" prefix */ if (need_pfx) { if (buf < end) *buf = '0'; ++buf; if (spec.base == 16) { if (buf < end) *buf = ('X' | locase); ++buf; } } /* zero or space padding */ if (!(spec.flags & LEFT)) { char c = (spec.flags & ZEROPAD) ? '0' : ' '; while (--spec.field_width >= 0) { if (buf < end) *buf = c; ++buf; } } /* hmm even more zero padding? */ while (i <= --spec.precision) { if (buf < end) *buf = '0'; ++buf; } /* actual digits of result */ while (--i >= 0) { if (buf < end) *buf = tmp[i]; ++buf; } /* trailing space padding */ while (--spec.field_width >= 0) { if (buf < end) *buf = ' '; ++buf; } return buf; } static noinline_for_stack char *string(char *buf, char *end, const char *s, struct printf_spec spec) { int len, i; if ((unsigned long)s < PAGE_SIZE) s = "(null)"; len = strnlen(s, spec.precision); if (!(spec.flags & LEFT)) { while (len < spec.field_width--) { if (buf < end) *buf = ' '; ++buf; } } for (i = 0; i < len; ++i) { if (buf < end) *buf = *s; ++buf; ++s; } while (len < spec.field_width--) { if (buf < end) *buf = ' '; ++buf; } return buf; } static noinline_for_stack char *symbol_string(char *buf, char *end, void *ptr, struct printf_spec spec, char ext) { unsigned long value = (unsigned long) ptr; #ifdef CONFIG_KALLSYMS char sym[KSYM_SYMBOL_LEN]; if (ext != 'f' && ext != 's') sprint_symbol(sym, value); else kallsyms_lookup(value, NULL, NULL, NULL, sym); return string(buf, end, sym, spec); #else spec.field_width = 2 * sizeof(void *); spec.flags |= SPECIAL | SMALL | ZEROPAD; spec.base = 16; return number(buf, end, value, spec); #endif } static noinline_for_stack char *resource_string(char *buf, char *end, struct resource *res, struct printf_spec spec, const char *fmt) { #ifndef IO_RSRC_PRINTK_SIZE #define IO_RSRC_PRINTK_SIZE 6 #endif #ifndef MEM_RSRC_PRINTK_SIZE #define MEM_RSRC_PRINTK_SIZE 10 #endif static const struct printf_spec io_spec = { .base = 16, .field_width = IO_RSRC_PRINTK_SIZE, .precision = -1, .flags = SPECIAL | SMALL | ZEROPAD, }; static const struct printf_spec mem_spec = { .base = 16, .field_width = MEM_RSRC_PRINTK_SIZE, .precision = -1, .flags = SPECIAL | SMALL | ZEROPAD, }; static const struct printf_spec bus_spec = { .base = 16, .field_width = 2, .precision = -1, .flags = SMALL | ZEROPAD, }; static const struct printf_spec dec_spec = { .base = 10, .precision = -1, .flags = 0, }; static const struct printf_spec str_spec = { .field_width = -1, .precision = 10, .flags = LEFT, }; static const struct printf_spec flag_spec = { .base = 16, .precision = -1, .flags = SPECIAL | SMALL, }; /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") #undef max #define max(a,b) ((a) > (b) ? (a) : (b)) char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; char *p = sym, *pend = sym + sizeof(sym); int decode = (fmt[0] == 'R') ? 1 : 0; const struct printf_spec *specp; *p++ = '['; if (res->flags & IORESOURCE_IO) { p = string(p, pend, "io ", str_spec); specp = &io_spec; } else if (res->flags & IORESOURCE_MEM) { p = string(p, pend, "mem ", str_spec); specp = &mem_spec; } else if (res->flags & IORESOURCE_IRQ) { p = string(p, pend, "irq ", str_spec); specp = &dec_spec; } else if (res->flags & IORESOURCE_DMA) { p = string(p, pend, "dma ", str_spec); specp = &dec_spec; } else if (res->flags & IORESOURCE_BUS) { p = string(p, pend, "bus ", str_spec); specp = &bus_spec; } else { p = string(p, pend, "??? ", str_spec); specp = &mem_spec; decode = 0; } p = number(p, pend, res->start, *specp); if (res->start != res->end) { *p++ = '-'; p = number(p, pend, res->end, *specp); } if (decode) { if (res->flags & IORESOURCE_MEM_64) p = string(p, pend, " 64bit", str_spec); if (res->flags & IORESOURCE_PREFETCH) p = string(p, pend, " pref", str_spec); if (res->flags & IORESOURCE_WINDOW) p = string(p, pend, " window", str_spec); if (res->flags & IORESOURCE_DISABLED) p = string(p, pend, " disabled", str_spec); } else { p = string(p, pend, " flags ", str_spec); p = number(p, pend, res->flags, flag_spec); } *p++ = ']'; *p = '\0'; return string(buf, end, sym, spec); } static noinline_for_stack char *mac_address_string(char *buf, char *end, u8 *addr, struct printf_spec spec, const char *fmt) { char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; char *p = mac_addr; int i; char separator; if (fmt[1] == 'F') { /* FDDI canonical format */ separator = '-'; } else { separator = ':'; } for (i = 0; i < 6; i++) { p = pack_hex_byte(p, addr[i]); if (fmt[0] == 'M' && i != 5) *p++ = separator; } *p = '\0'; return string(buf, end, mac_addr, spec); } static noinline_for_stack char *ip4_string(char *p, const u8 *addr, const char *fmt) { int i; bool leading_zeros = (fmt[0] == 'i'); int index; int step; switch (fmt[2]) { case 'h': #ifdef __BIG_ENDIAN index = 0; step = 1; #else index = 3; step = -1; #endif break; case 'l': index = 3; step = -1; break; case 'n': case 'b': default: index = 0; step = 1; break; } for (i = 0; i < 4; i++) { char temp[3]; /* hold each IP quad in reverse order */ int digits = put_dec_trunc(temp, addr[index]) - temp; if (leading_zeros) { if (digits < 3) *p++ = '0'; if (digits < 2) *p++ = '0'; } /* reverse the digits in the quad */ while (digits--) *p++ = temp[digits]; if (i < 3) *p++ = '.'; index += step; } *p = '\0'; return p; } static noinline_for_stack char *ip4_addr_string(char *buf, char *end, const u8 *addr, struct printf_spec spec, const char *fmt) { char ip4_addr[sizeof("255.255.255.255")]; ip4_string(ip4_addr, addr, fmt); return string(buf, end, ip4_addr, spec); } int kptr_restrict = 1; /* * Show a '%p' thing. A kernel extension is that the '%p' is followed * by an extra set of alphanumeric characters that are extended format * specifiers. * * Right now we handle: * * - 'F' For symbolic function descriptor pointers with offset * - 'f' For simple symbolic function names without offset * - 'S' For symbolic direct pointers with offset * - 's' For symbolic direct pointers without offset * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] * - 'M' For a 6-byte MAC address, it prints the address in the * usual colon-separated hex notation * - 'm' For a 6-byte MAC address, it prints the hex address without colons * - 'MF' For a 6-byte MAC FDDI address, it prints the address * with a dash-separated hex notation * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) * IPv6 uses colon separated network-order 16 bit hex with leading 0's * - 'i' [46] for 'raw' IPv4/IPv6 addresses * IPv6 omits the colons (01020304...0f) * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order * - 'I6c' for IPv6 addresses printed as specified by * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" * Options for %pU are: * b big endian lower case hex (default) * B big endian UPPER case hex * l little endian lower case hex * L little endian UPPER case hex * big endian output byte order is: * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] * little endian output byte order is: * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] * - 'V' For a struct va_format which contains a format string * and va_list *, * call vsnprintf(->format, *->va_list). * Implements a "recursive vsnprintf". * Do not use this feature without some mechanism to verify the * correctness of the format string and va_list arguments. * - 'K' For a kernel pointer that should be hidden from unprivileged users * * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 * function pointers are really function descriptors, which contain a * pointer to the real address. */ static noinline_for_stack char *pointer(const char *fmt, char *buf, char *end, void *ptr, struct printf_spec spec) { if (!ptr) { /* * Print (null) with the same width as a pointer so it makes * tabular output look nice. */ if (spec.field_width == -1) spec.field_width = 2 * sizeof(void *); return string(buf, end, "(null)", spec); } switch (*fmt) { case 'F': case 'f': ptr = dereference_function_descriptor(ptr); /* Fallthrough */ case 'S': case 's': return symbol_string(buf, end, ptr, spec, *fmt); case 'R': case 'r': return resource_string(buf, end, ptr, spec, fmt); case 'M': /* Colon separated: 00:01:02:03:04:05 */ case 'm': /* Contiguous: 000102030405 */ /* [mM]F (FDDI, bit reversed) */ return mac_address_string(buf, end, ptr, spec, fmt); case 'I': /* Formatted IP supported * 4: 1.2.3.4 * 6: 0001:0203:...:0708 * 6c: 1::708 or 1::1.2.3.4 */ case 'i': /* Contiguous: * 4: 001.002.003.004 * 6: 000102...0f */ switch (fmt[1]) { case '4': return ip4_addr_string(buf, end, ptr, spec, fmt); } break; case 'V': return buf + vsnprintf(buf, end - buf, ((struct va_format *)ptr)->fmt, *(((struct va_format *)ptr)->va)); } spec.flags |= SMALL; if (spec.field_width == -1) { spec.field_width = 2 * sizeof(void *); spec.flags |= ZEROPAD; } spec.base = 16; return number(buf, end, (unsigned long) ptr, spec); } /* * Helper function to decode printf style format. * Each call decode a token from the format and return the * number of characters read (or likely the delta where it wants * to go on the next call). * The decoded token is returned through the parameters * * 'h', 'l', or 'L' for integer fields * 'z' support added 23/7/1999 S.H. * 'z' changed to 'Z' --davidm 1/25/99 * 't' added for ptrdiff_t * * @fmt: the format string * @type of the token returned * @flags: various flags such as +, -, # tokens.. * @field_width: overwritten width * @base: base of the number (octal, hex, ...) * @precision: precision of a number * @qualifier: qualifier of a number (long, size_t, ...) */ static noinline_for_stack int format_decode(const char *fmt, struct printf_spec *spec) { const char *start = fmt; /* we finished early by reading the field width */ if (spec->type == FORMAT_TYPE_WIDTH) { if (spec->field_width < 0) { spec->field_width = -spec->field_width; spec->flags |= LEFT; } spec->type = FORMAT_TYPE_NONE; goto precision; } /* we finished early by reading the precision */ if (spec->type == FORMAT_TYPE_PRECISION) { if (spec->precision < 0) spec->precision = 0; spec->type = FORMAT_TYPE_NONE; goto qualifier; } /* By default */ spec->type = FORMAT_TYPE_NONE; for (; *fmt ; ++fmt) { if (*fmt == '%') break; } /* Return the current non-format string */ if (fmt != start || !*fmt) return fmt - start; /* Process flags */ spec->flags = 0; while (1) { /* this also skips first '%' */ bool found = true; ++fmt; switch (*fmt) { case '-': spec->flags |= LEFT; break; case '+': spec->flags |= PLUS; break; case ' ': spec->flags |= SPACE; break; case '#': spec->flags |= SPECIAL; break; case '0': spec->flags |= ZEROPAD; break; default: found = false; } if (!found) break; } /* get field width */ spec->field_width = -1; if (isdigit(*fmt)) spec->field_width = skip_atoi(&fmt); else if (*fmt == '*') { /* it's the next argument */ spec->type = FORMAT_TYPE_WIDTH; return ++fmt - start; } precision: /* get the precision */ spec->precision = -1; if (*fmt == '.') { ++fmt; if (isdigit(*fmt)) { spec->precision = skip_atoi(&fmt); if (spec->precision < 0) spec->precision = 0; } else if (*fmt == '*') { /* it's the next argument */ spec->type = FORMAT_TYPE_PRECISION; return ++fmt - start; } } qualifier: /* get the conversion qualifier */ spec->qualifier = -1; if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || TOLOWER(*fmt) == 'z' || *fmt == 't') { spec->qualifier = *fmt++; if (unlikely(spec->qualifier == *fmt)) { if (spec->qualifier == 'l') { spec->qualifier = 'L'; ++fmt; } else if (spec->qualifier == 'h') { spec->qualifier = 'H'; ++fmt; } } } /* default base */ spec->base = 10; switch (*fmt) { case 'c': spec->type = FORMAT_TYPE_CHAR; return ++fmt - start; case 's': spec->type = FORMAT_TYPE_STR; return ++fmt - start; case 'p': spec->type = FORMAT_TYPE_PTR; return fmt - start; /* skip alnum */ case 'n': spec->type = FORMAT_TYPE_NRCHARS; return ++fmt - start; case '%': spec->type = FORMAT_TYPE_PERCENT_CHAR; return ++fmt - start; /* integer number formats - set up the flags and "break" */ case 'o': spec->base = 8; break; case 'x': spec->flags |= SMALL; case 'X': spec->base = 16; break; case 'd': case 'i': spec->flags |= SIGN; case 'u': break; default: spec->type = FORMAT_TYPE_INVALID; return fmt - start; } if (spec->qualifier == 'L') spec->type = FORMAT_TYPE_LONG_LONG; else if (spec->qualifier == 'l') { if (spec->flags & SIGN) spec->type = FORMAT_TYPE_LONG; else spec->type = FORMAT_TYPE_ULONG; } else if (TOLOWER(spec->qualifier) == 'z') { spec->type = FORMAT_TYPE_SIZE_T; } else if (spec->qualifier == 't') { spec->type = FORMAT_TYPE_PTRDIFF; } else if (spec->qualifier == 'H') { if (spec->flags & SIGN) spec->type = FORMAT_TYPE_BYTE; else spec->type = FORMAT_TYPE_UBYTE; } else if (spec->qualifier == 'h') { if (spec->flags & SIGN) spec->type = FORMAT_TYPE_SHORT; else spec->type = FORMAT_TYPE_USHORT; } else { if (spec->flags & SIGN) spec->type = FORMAT_TYPE_INT; else spec->type = FORMAT_TYPE_UINT; } return ++fmt - start; } /** * vsnprintf - Format a string and place it in a buffer * @buf: The buffer to place the result into * @size: The size of the buffer, including the trailing null space * @fmt: The format string to use * @args: Arguments for the format string * * This function follows C99 vsnprintf, but has some extensions: * %pS output the name of a text symbol with offset * %ps output the name of a text symbol without offset * %pF output the name of a function pointer with its offset * %pf output the name of a function pointer without its offset * %pR output the address range in a struct resource with decoded flags * %pr output the address range in a struct resource with raw flags * %pM output a 6-byte MAC address with colons * %pm output a 6-byte MAC address without colons * %pI4 print an IPv4 address without leading zeros * %pi4 print an IPv4 address with leading zeros * %pI6 print an IPv6 address with colons * %pi6 print an IPv6 address without colons * %pI6c print an IPv6 address as specified by * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper * case. * %n is ignored * * The return value is the number of characters which would * be generated for the given input, excluding the trailing * '\0', as per ISO C99. If you want to have the exact * number of characters written into @buf as return value * (not including the trailing '\0'), use vscnprintf(). If the * return is greater than or equal to @size, the resulting * string is truncated. * * Call this function if you are already dealing with a va_list. * You probably want snprintf() instead. */ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) { unsigned long long num; char *str, *end; struct printf_spec spec = {0}; /* Reject out-of-range values early. Large positive sizes are used for unknown buffer sizes. */ if ((int)size < 0) return 0; str = buf; end = buf + size; /* Make sure end is always >= buf */ if (end < buf) { end = ((void *)-1); size = end - buf; } while (*fmt) { const char *old_fmt = fmt; int read = format_decode(fmt, &spec); fmt += read; switch (spec.type) { case FORMAT_TYPE_NONE: { int copy = read; if (str < end) { if (copy > end - str) copy = end - str; memcpy(str, old_fmt, copy); } str += read; break; } case FORMAT_TYPE_WIDTH: spec.field_width = va_arg(args, int); break; case FORMAT_TYPE_PRECISION: spec.precision = va_arg(args, int); break; case FORMAT_TYPE_CHAR: { char c; if (!(spec.flags & LEFT)) { while (--spec.field_width > 0) { if (str < end) *str = ' '; ++str; } } c = (unsigned char) va_arg(args, int); if (str < end) *str = c; ++str; while (--spec.field_width > 0) { if (str < end) *str = ' '; ++str; } break; } case FORMAT_TYPE_STR: str = string(str, end, va_arg(args, char *), spec); break; case FORMAT_TYPE_PTR: str = pointer(fmt+1, str, end, va_arg(args, void *), spec); while (isalnum(*fmt)) fmt++; break; case FORMAT_TYPE_PERCENT_CHAR: if (str < end) *str = '%'; ++str; break; case FORMAT_TYPE_INVALID: if (str < end) *str = '%'; ++str; break; case FORMAT_TYPE_NRCHARS: { u8 qualifier = spec.qualifier; if (qualifier == 'l') { long *ip = va_arg(args, long *); *ip = (str - buf); } else if (TOLOWER(qualifier) == 'z') { size_t *ip = va_arg(args, size_t *); *ip = (str - buf); } else { int *ip = va_arg(args, int *); *ip = (str - buf); } break; } default: switch (spec.type) { case FORMAT_TYPE_LONG_LONG: num = va_arg(args, long long); break; case FORMAT_TYPE_ULONG: num = va_arg(args, unsigned long); break; case FORMAT_TYPE_LONG: num = va_arg(args, long); break; case FORMAT_TYPE_SIZE_T: num = va_arg(args, size_t); break; case FORMAT_TYPE_PTRDIFF: num = va_arg(args, ptrdiff_t); break; case FORMAT_TYPE_UBYTE: num = (unsigned char) va_arg(args, int); break; case FORMAT_TYPE_BYTE: num = (signed char) va_arg(args, int); break; case FORMAT_TYPE_USHORT: num = (unsigned short) va_arg(args, int); break; case FORMAT_TYPE_SHORT: num = (short) va_arg(args, int); break; case FORMAT_TYPE_INT: num = (int) va_arg(args, int); break; default: num = va_arg(args, unsigned int); } str = number(str, end, num, spec); } } if (size > 0) { if (str < end) *str = '\0'; else end[-1] = '\0'; } /* the trailing null byte doesn't count towards the total */ return str-buf; } EXPORT_SYMBOL(vsnprintf); int vsprintf(char *buf, const char *fmt, va_list args) { return vsnprintf(buf, INT_MAX, fmt, args); } /** * snprintf - Format a string and place it in a buffer * @buf: The buffer to place the result into * @size: The size of the buffer, including the trailing null space * @fmt: The format string to use * @...: Arguments for the format string * * The return value is the number of characters which would be * generated for the given input, excluding the trailing null, * as per ISO C99. If the return is greater than or equal to * @size, the resulting string is truncated. * * See the vsnprintf() documentation for format string extensions over C99. */ int snprintf(char *buf, size_t size, const char *fmt, ...) { va_list args; int i; va_start(args, fmt); i = vsnprintf(buf, size, fmt, args); va_end(args); return i; } EXPORT_SYMBOL(snprintf); /** * sprintf - Format a string and place it in a buffer * @buf: The buffer to place the result into * @fmt: The format string to use * @...: Arguments for the format string * * The function returns the number of characters written * into @buf. Use snprintf() or scnprintf() in order to avoid * buffer overflows. * * See the vsnprintf() documentation for format string extensions over C99. */ int sprintf(char *buf, const char *fmt, ...) { va_list args; int i; va_start(args, fmt); i = vsnprintf(buf, INT_MAX, fmt, args); va_end(args); return i; }