From: Chad Goodman Date: Sun, 25 Nov 2012 08:56:52 +0000 (-0800) Subject: KSTRTO*: converting strings to integers X-Git-Url: https://ziggy471.com/git/gitweb.cgi?p=ziggy471-sgn2-jb.git;a=commitdiff;h=b0e78db03980b0223eaa068629b584f05b79881d KSTRTO*: converting strings to integers Signed-off-by: Ziggy --- --- a/include/linux/ctype.h +++ b/include/linux/ctype.h @@ -52,4 +52,13 @@ static inline unsigned char __toupper(un #define tolower(c) __tolower(c) #define toupper(c) __toupper(c) +/* + * Fast implementation of tolower() for internal usage. Do not use in your + * code. + */ +static inline char _tolower(const char c) +{ + return c | 0x20; +} + #endif --- a/lib/kstrtox.c +++ b/lib/kstrtox.c @@ -18,31 +18,40 @@ #include #include #include +#include "kstrtox.h" -static inline char _tolower(const char c) +const char *_parse_integer_fixup_radix(const char *s, unsigned int *base) { - return c | 0x20; -} - -static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res) -{ - unsigned long long acc; - int ok; - - if (base == 0) { + if (*base == 0) { if (s[0] == '0') { if (_tolower(s[1]) == 'x' && isxdigit(s[2])) - base = 16; + *base = 16; else - base = 8; + *base = 8; } else - base = 10; + *base = 10; } - if (base == 16 && s[0] == '0' && _tolower(s[1]) == 'x') + if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x') s += 2; + return s; +} + +/* + * Convert non-negative integer string representation in explicitly given radix + * to an integer. + * Return number of characters consumed maybe or-ed with overflow bit. + * If overflow occurs, result integer (incorrect) is still returned. + * + * Don't you dare use this function. + */ +unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *res) +{ + unsigned int rv; + int overflow; - acc = 0; - ok = 0; + *res = 0; + rv = 0; + overflow = 0; while (*s) { unsigned int val; @@ -50,23 +59,40 @@ static int _kstrtoull(const char *s, uns val = *s - '0'; else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f') val = _tolower(*s) - 'a' + 10; - else if (*s == '\n' && *(s + 1) == '\0') - break; else - return -EINVAL; + break; if (val >= base) - return -EINVAL; - if (acc > div_u64(ULLONG_MAX - val, base)) - return -ERANGE; - acc = acc * base + val; - ok = 1; - + break; + if (*res > div_u64(ULLONG_MAX - val, base)) + overflow = 1; + *res = *res * base + val; + rv++; s++; } - if (!ok) + if (overflow) + rv |= KSTRTOX_OVERFLOW; + return rv; +} + +static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res) +{ + unsigned long long _res; + unsigned int rv; + + s = _parse_integer_fixup_radix(s, &base); + rv = _parse_integer(s, base, &_res); + if (rv & KSTRTOX_OVERFLOW) + return -ERANGE; + rv &= ~KSTRTOX_OVERFLOW; + if (rv == 0) + return -EINVAL; + s += rv; + if (*s == '\n') + s++; + if (*s) return -EINVAL; - *res = acc; + *res = _res; return 0; } --- /dev/null +++ b/lib/kstrtox.h @@ -0,0 +1,8 @@ +#ifndef _LIB_KSTRTOX_H +#define _LIB_KSTRTOX_H + +#define KSTRTOX_OVERFLOW (1U << 31) +const char *_parse_integer_fixup_radix(const char *s, unsigned int *base); +unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *res); + +#endif --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -31,20 +31,7 @@ #include #include /* for dereference_function_descriptor() */ -/* 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; - } -} +#include "kstrtox.h" /** * simple_strtoull - convert a string to an unsigned long long @@ -54,23 +41,14 @@ static unsigned int simple_guess_base(co */ unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) { - unsigned long long result = 0; + unsigned long long result; + unsigned int rv; - if (!base) - base = simple_guess_base(cp); + cp = _parse_integer_fixup_radix(cp, &base); + rv = _parse_integer(cp, base, &result); + /* FIXME */ + cp += (rv & ~KSTRTOX_OVERFLOW); - 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; @@ -1010,9 +988,15 @@ char *pointer(const char *fmt, char *buf case 'U': return uuid_string(buf, end, ptr, spec, fmt); case 'V': - return buf + vsnprintf(buf, end > buf ? end - buf : 0, - ((struct va_format *)ptr)->fmt, - *(((struct va_format *)ptr)->va)); + { + va_list va; + + va_copy(va, *((struct va_format *)ptr)->va); + buf += vsnprintf(buf, end > buf ? end - buf : 0, + ((struct va_format *)ptr)->fmt, va); + va_end(va); + return buf; + } case 'K': /* * %pK cannot be used in IRQ context because its test @@ -1146,8 +1130,8 @@ precision: qualifier: /* get the conversion qualifier */ spec->qualifier = -1; - if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || - TOLOWER(*fmt) == 'z' || *fmt == 't') { + if (*fmt == 'h' || _tolower(*fmt) == 'l' || + _tolower(*fmt) == 'z' || *fmt == 't') { spec->qualifier = *fmt++; if (unlikely(spec->qualifier == *fmt)) { if (spec->qualifier == 'l') { @@ -1214,7 +1198,7 @@ qualifier: spec->type = FORMAT_TYPE_LONG; else spec->type = FORMAT_TYPE_ULONG; - } else if (TOLOWER(spec->qualifier) == 'z') { + } else if (_tolower(spec->qualifier) == 'z') { spec->type = FORMAT_TYPE_SIZE_T; } else if (spec->qualifier == 't') { spec->type = FORMAT_TYPE_PTRDIFF; @@ -1259,8 +1243,7 @@ qualifier: * %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 + * %pI6c print an IPv6 address as specified by RFC 5952 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper * case. * %n is ignored @@ -1373,7 +1356,7 @@ int vsnprintf(char *buf, size_t size, co if (qualifier == 'l') { long *ip = va_arg(args, long *); *ip = (str - buf); - } else if (TOLOWER(qualifier) == 'z') { + } else if (_tolower(qualifier) == 'z') { size_t *ip = va_arg(args, size_t *); *ip = (str - buf); } else { @@ -1660,7 +1643,7 @@ do { \ void *skip_arg; if (qualifier == 'l') skip_arg = va_arg(args, long *); - else if (TOLOWER(qualifier) == 'z') + else if (_tolower(qualifier) == 'z') skip_arg = va_arg(args, size_t *); else skip_arg = va_arg(args, int *); @@ -1966,8 +1949,8 @@ int vsscanf(const char *buf, const char /* get conversion qualifier */ qualifier = -1; - if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || - TOLOWER(*fmt) == 'z') { + if (*fmt == 'h' || _tolower(*fmt) == 'l' || + _tolower(*fmt) == 'z') { qualifier = *fmt++; if (unlikely(qualifier == *fmt)) { if (qualifier == 'h') {