diff options
Diffstat (limited to 'lib/vsprintf.c')
| -rw-r--r-- | lib/vsprintf.c | 1221 |
1 files changed, 1221 insertions, 0 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c new file mode 100644 index 0000000..a013bbc --- /dev/null +++ b/lib/vsprintf.c @@ -0,0 +1,1221 @@ +/* + * 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 <crutcher+kernel@datastacks.com> + * - changed to provide snprintf and vsnprintf functions + * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> + * - scnprintf and vscnprintf + */ + +#include <stdarg.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/ctype.h> +#include <linux/kernel.h> +#include <linux/kallsyms.h> +#include <linux/uaccess.h> +#include <linux/ioport.h> + +#include <asm/page.h> /* for PAGE_SIZE */ +#include <asm/div64.h> +#include <asm/sections.h> /* 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; + } +} + +/** + * 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) +{ + unsigned 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_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_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_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); +} + +/** + * 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; + size_t len; + + *res = 0; + len = strlen(cp); + if (len == 0) + return -EINVAL; + + val = simple_strtoul(cp, &tail, base); + if ((*tail == '\0') || + ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) { + *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; + size_t len; + + *res = 0; + len = strlen(cp); + if (len == 0) + return -EINVAL; + + val = simple_strtoull(cp, &tail, base); + if ((*tail == '\0') || + ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) { + *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 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 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 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 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 /* Must be 32 == 0x20 */ +#define SPECIAL 64 /* 0x */ + +static char *number(char *buf, char *end, unsigned long long num, int base, int size, int precision, int type) +{ + /* 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 = ((type & SPECIAL) && base != 10); + int i; + + /* locase = 0 or 0x20. ORing digits or letters with 'locase' + * produces same digits or (maybe lowercased) letters */ + locase = (type & SMALL); + if (type & LEFT) + type &= ~ZEROPAD; + sign = 0; + if (type & SIGN) { + if ((signed long long) num < 0) { + sign = '-'; + num = - (signed long long) num; + size--; + } else if (type & PLUS) { + sign = '+'; + size--; + } else if (type & SPACE) { + sign = ' '; + size--; + } + } + if (need_pfx) { + size--; + if (base == 16) + size--; + } + + /* 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 (base != 10) { /* 8 or 16 */ + int mask = base - 1; + int shift = 3; + if (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 > precision) + precision = i; + /* leading space padding */ + size -= precision; + if (!(type & (ZEROPAD+LEFT))) { + while(--size >= 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 (base == 16) { + if (buf < end) + *buf = ('X' | locase); + ++buf; + } + } + /* zero or space padding */ + if (!(type & LEFT)) { + char c = (type & ZEROPAD) ? '0' : ' '; + while (--size >= 0) { + if (buf < end) + *buf = c; + ++buf; + } + } + /* hmm even more zero padding? */ + while (i <= --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 (--size >= 0) { + if (buf < end) + *buf = ' '; + ++buf; + } + return buf; +} + +static char *string(char *buf, char *end, char *s, int field_width, int precision, int flags) +{ + int len, i; + + if ((unsigned long)s < PAGE_SIZE) + s = "<NULL>"; + + len = strnlen(s, precision); + + if (!(flags & LEFT)) { + while (len < field_width--) { + if (buf < end) + *buf = ' '; + ++buf; + } + } + for (i = 0; i < len; ++i) { + if (buf < end) + *buf = *s; + ++buf; ++s; + } + while (len < field_width--) { + if (buf < end) + *buf = ' '; + ++buf; + } + return buf; +} + +static char *symbol_string(char *buf, char *end, void *ptr, int field_width, int precision, int flags) +{ + unsigned long value = (unsigned long) ptr; +#ifdef CONFIG_KALLSYMS + char sym[KSYM_SYMBOL_LEN]; + sprint_symbol(sym, value); + return string(buf, end, sym, field_width, precision, flags); +#else + field_width = 2*sizeof(void *); + flags |= SPECIAL | SMALL | ZEROPAD; + return number(buf, end, value, 16, field_width, precision, flags); +#endif +} + +static char *resource_string(char *buf, char *end, struct resource *res, int field_width, int precision, int flags) +{ +#ifndef IO_RSRC_PRINTK_SIZE +#define IO_RSRC_PRINTK_SIZE 4 +#endif + +#ifndef MEM_RSRC_PRINTK_SIZE +#define MEM_RSRC_PRINTK_SIZE 8 +#endif + + /* room for the actual numbers, the two "0x", -, [, ] and the final zero */ + char sym[4*sizeof(resource_size_t) + 8]; + char *p = sym, *pend = sym + sizeof(sym); + int size = -1; + + if (res->flags & IORESOURCE_IO) + size = IO_RSRC_PRINTK_SIZE; + else if (res->flags & IORESOURCE_MEM) + size = MEM_RSRC_PRINTK_SIZE; + + *p++ = '['; + p = number(p, pend, res->start, 16, size, -1, SPECIAL | SMALL | ZEROPAD); + *p++ = '-'; + p = number(p, pend, res->end, 16, size, -1, SPECIAL | SMALL | ZEROPAD); + *p++ = ']'; + *p = 0; + + return string(buf, end, sym, field_width, precision, flags); +} + +/* + * 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 + * - 'S' For symbolic direct pointers + * - 'R' For a struct resource pointer, it prints the range of + * addresses (not the name nor the flags) + * + * 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 char *pointer(const char *fmt, char *buf, char *end, void *ptr, int field_width, int precision, int flags) +{ + switch (*fmt) { + case 'F': + ptr = dereference_function_descriptor(ptr); + /* Fallthrough */ + case 'S': + return symbol_string(buf, end, ptr, field_width, precision, flags); + case 'R': + return resource_string(buf, end, ptr, field_width, precision, flags); + } + flags |= SMALL; + if (field_width == -1) { + field_width = 2*sizeof(void *); + flags |= ZEROPAD; + } + return number(buf, end, (unsigned long) ptr, 16, field_width, precision, flags); +} + +/** + * 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 + * %pF output the name of a function pointer + * %pR output the address range in a struct resource + * + * 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; + int base; + char *str, *end, c; + + int flags; /* flags to number() */ + + int field_width; /* width of output field */ + int precision; /* min. # of digits for integers; max + number of chars for from string */ + int qualifier; /* '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 */ + + /* Reject out-of-range values early. Large positive sizes are + used for unknown buffer sizes. */ + if (unlikely((int) size < 0)) { + /* There can be only one.. */ + static char warn = 1; + WARN_ON(warn); + warn = 0; + return 0; + } + + str = buf; + end = buf + size; + + /* Make sure end is always >= buf */ + if (end < buf) { + end = ((void *)-1); + size = end - buf; + } + + for (; *fmt ; ++fmt) { + if (*fmt != '%') { + if (str < end) + *str = *fmt; + ++str; + continue; + } + + /* process flags */ + flags = 0; + repeat: + ++fmt; /* this also skips first '%' */ + switch (*fmt) { + case '-': flags |= LEFT; goto repeat; + case '+': flags |= PLUS; goto repeat; + case ' ': flags |= SPACE; goto repeat; + case '#': flags |= SPECIAL; goto repeat; + case '0': flags |= ZEROPAD; goto repeat; + } + + /* get field width */ + field_width = -1; + if (isdigit(*fmt)) + field_width = skip_atoi(&fmt); + else if (*fmt == '*') { + ++fmt; + /* it's the next argument */ + field_width = va_arg(args, int); + if (field_width < 0) { + field_width = -field_width; + flags |= LEFT; + } + } + + /* get the precision */ + precision = -1; + if (*fmt == '.') { + ++fmt; + if (isdigit(*fmt)) + precision = skip_atoi(&fmt); + else if (*fmt == '*') { + ++fmt; + /* it's the next argument */ + precision = va_arg(args, int); + } + if (precision < 0) + precision = 0; + } + + /* get the conversion qualifier */ + qualifier = -1; + if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || + *fmt =='Z' || *fmt == 'z' || *fmt == 't') { + qualifier = *fmt; + ++fmt; + if (qualifier == 'l' && *fmt == 'l') { + qualifier = 'L'; + ++fmt; + } + } + + /* default base */ + base = 10; + + switch (*fmt) { + case 'c': + if (!(flags & LEFT)) { + while (--field_width > 0) { + if (str < end) + *str = ' '; + ++str; + } + } + c = (unsigned char) va_arg(args, int); + if (str < end) + *str = c; + ++str; + while (--field_width > 0) { + if (str < end) + *str = ' '; + ++str; + } + continue; + + case 's': + str = string(str, end, va_arg(args, char *), field_width, precision, flags); + continue; + + case 'p': + str = pointer(fmt+1, str, end, + va_arg(args, void *), + field_width, precision, flags); + /* Skip all alphanumeric pointer suffixes */ + while (isalnum(fmt[1])) + fmt++; + continue; + + case 'n': + /* FIXME: + * What does C99 say about the overflow case here? */ + if (qualifier == 'l') { + long * ip = va_arg(args, long *); + *ip = (str - buf); + } else if (qualifier == 'Z' || qualifier == 'z') { + size_t * ip = va_arg(args, size_t *); + *ip = (str - buf); + } else { + int * ip = va_arg(args, int *); + *ip = (str - buf); + } + continue; + + case '%': + if (str < end) + *str = '%'; + ++str; + continue; + + /* integer number formats - set up the flags and "break" */ + case 'o': + base = 8; + break; + + case 'x': + flags |= SMALL; + case 'X': + base = 16; + break; + + case 'd': + case 'i': + flags |= SIGN; + case 'u': + break; + + default: + if (str < end) + *str = '%'; + ++str; + if (*fmt) { + if (str < end) + *str = *fmt; + ++str; + } else { + --fmt; + } + continue; + } + if (qualifier == 'L') + num = va_arg(args, long long); + else if (qualifier == 'l') { + num = va_arg(args, unsigned long); + if (flags & SIGN) + num = (signed long) num; + } else if (qualifier == 'Z' || qualifier == 'z') { + num = va_arg(args, size_t); + } else if (qualifier == 't') { + num = va_arg(args, ptrdiff_t); + } else if (qualifier == 'h') { + num = (unsigned short) va_arg(args, int); + if (flags & SIGN) + num = (signed short) num; + } else { + num = va_arg(args, unsigned int); + if (flags & SIGN) + num = (signed int) num; + } + str = number(str, end, num, base, + field_width, precision, flags); + } + 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); + +/** + * vscnprintf - 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 + * + * The return value is the number of characters which have been written into + * the @buf not including the trailing '\0'. If @size is <= 0 the function + * returns 0. + * + * Call this function if you are already dealing with a va_list. + * You probably want scnprintf() instead. + * + * See the vsnprintf() documentation for format string extensions over C99. + */ +int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) +{ + int i; + + i=vsnprintf(buf,size,fmt,args); + return (i >= size) ? (size - 1) : i; +} +EXPORT_SYMBOL(vscnprintf); + +/** + * 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); + +/** + * scnprintf - 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 written into @buf not including + * the trailing '\0'. If @size is <= 0 the function returns 0. + */ + +int scnprintf(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 >= size) ? (size - 1) : i; +} +EXPORT_SYMBOL(scnprintf); + +/** + * vsprintf - Format a string and place it in a buffer + * @buf: The buffer to place the result into + * @fmt: The format string to use + * @args: Arguments for the format string + * + * The function returns the number of characters written + * into @buf. Use vsnprintf() or vscnprintf() in order to avoid + * buffer overflows. + * + * Call this function if you are already dealing with a va_list. + * You probably want sprintf() instead. + * + * See the vsnprintf() documentation for format string extensions over C99. + */ +int vsprintf(char *buf, const char *fmt, va_list args) +{ + return vsnprintf(buf, INT_MAX, fmt, args); +} +EXPORT_SYMBOL(vsprintf); + +/** + * 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; +} +EXPORT_SYMBOL(sprintf); + +/** + * vsscanf - Unformat a buffer into a list of arguments + * @buf: input buffer + * @fmt: format of buffer + * @args: arguments + */ +int vsscanf(const char * buf, const char * fmt, va_list args) +{ + const char *str = buf; + char *next; + char digit; + int num = 0; + int qualifier; + int base; + int field_width; + int is_sign = 0; + + while(*fmt && *str) { + /* skip any white space in format */ + /* white space in format matchs any amount of + * white space, including none, in the input. + */ + if (isspace(*fmt)) { + while (isspace(*fmt)) + ++fmt; + while (isspace(*str)) + ++str; + } + + /* anything that is not a conversion must match exactly */ + if (*fmt != '%' && *fmt) { + if (*fmt++ != *str++) + break; + continue; + } + + if (!*fmt) + break; + ++fmt; + + /* skip this conversion. + * advance both strings to next white space + */ + if (*fmt == '*') { + while (!isspace(*fmt) && *fmt) + fmt++; + while (!isspace(*str) && *str) + str++; + continue; + } + + /* get field width */ + field_width = -1; + if (isdigit(*fmt)) + field_width = skip_atoi(&fmt); + + /* get conversion qualifier */ + qualifier = -1; + if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || + *fmt == 'Z' || *fmt == 'z') { + qualifier = *fmt++; + if (unlikely(qualifier == *fmt)) { + if (qualifier == 'h') { + qualifier = 'H'; + fmt++; + } else if (qualifier == 'l') { + qualifier = 'L'; + fmt++; + } + } + } + base = 10; + is_sign = 0; + + if (!*fmt || !*str) + break; + + switch(*fmt++) { + case 'c': + { + char *s = (char *) va_arg(args,char*); + if (field_width == -1) + field_width = 1; + do { + *s++ = *str++; + } while (--field_width > 0 && *str); + num++; + } + continue; + case 's': + { + char *s = (char *) va_arg(args, char *); + if(field_width == -1) + field_width = INT_MAX; + /* first, skip leading white space in buffer */ + while (isspace(*str)) + str++; + + /* now copy until next white space */ + while (*str && !isspace(*str) && field_width--) { + *s++ = *str++; + } + *s = '\0'; + num++; + } + continue; + case 'n': + /* return number of characters read so far */ + { + int *i = (int *)va_arg(args,int*); + *i = str - buf; + } + continue; + case 'o': + base = 8; + break; + case 'x': + case 'X': + base = 16; + break; + case 'i': + base = 0; + case 'd': + is_sign = 1; + case 'u': + break; + case '%': + /* looking for '%' in str */ + if (*str++ != '%') + return num; + continue; + default: + /* invalid format; stop here */ + return num; + } + + /* have some sort of integer conversion. + * first, skip white space in buffer. + */ + while (isspace(*str)) + str++; + + digit = *str; + if (is_sign && digit == '-') + digit = *(str + 1); + + if (!digit + || (base == 16 && !isxdigit(digit)) + || (base == 10 && !isdigit(digit)) + || (base == 8 && (!isdigit(digit) || digit > '7')) + || (base == 0 && !isdigit(digit))) + break; + + switch(qualifier) { + case 'H': /* that's 'hh' in format */ + if (is_sign) { + signed char *s = (signed char *) va_arg(args,signed char *); + *s = (signed char) simple_strtol(str,&next,base); + } else { + unsigned char *s = (unsigned char *) va_arg(args, unsigned char *); + *s = (unsigned char) simple_strtoul(str, &next, base); + } + break; + case 'h': + if (is_sign) { + short *s = (short *) va_arg(args,short *); + *s = (short) simple_strtol(str,&next,base); + } else { + unsigned short *s = (unsigned short *) va_arg(args, unsigned short *); + *s = (unsigned short) simple_strtoul(str, &next, base); + } + break; + case 'l': + if (is_sign) { + long *l = (long *) va_arg(args,long *); + *l = simple_strtol(str,&next,base); + } else { + unsigned long *l = (unsigned long*) va_arg(args,unsigned long*); + *l = simple_strtoul(str,&next,base); + } + break; + case 'L': + if (is_sign) { + long long *l = (long long*) va_arg(args,long long *); + *l = simple_strtoll(str,&next,base); + } else { + unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*); + *l = simple_strtoull(str,&next,base); + } + break; + case 'Z': + case 'z': + { + size_t *s = (size_t*) va_arg(args,size_t*); + *s = (size_t) simple_strtoul(str,&next,base); + } + break; + default: + if (is_sign) { + int *i = (int *) va_arg(args, int*); + *i = (int) simple_strtol(str,&next,base); + } else { + unsigned int *i = (unsigned int*) va_arg(args, unsigned int*); + *i = (unsigned int) simple_strtoul(str,&next,base); + } + break; + } + num++; + + if (!next) + break; + str = next; + } + + /* + * Now we've come all the way through so either the input string or the + * format ended. In the former case, there can be a %n at the current + * position in the format that needs to be filled. + */ + if (*fmt == '%' && *(fmt + 1) == 'n') { + int *p = (int *)va_arg(args, int *); + *p = str - buf; + } + + return num; +} +EXPORT_SYMBOL(vsscanf); + +/** + * sscanf - Unformat a buffer into a list of arguments + * @buf: input buffer + * @fmt: formatting of buffer + * @...: resulting arguments + */ +int sscanf(const char * buf, const char * fmt, ...) +{ + va_list args; + int i; + + va_start(args,fmt); + i = vsscanf(buf,fmt,args); + va_end(args); + return i; +} +EXPORT_SYMBOL(sscanf); |
