diff options
Diffstat (limited to 'lib_generic/vsprintf.c')
-rw-r--r-- | lib_generic/vsprintf.c | 479 |
1 files changed, 373 insertions, 106 deletions
diff --git a/lib_generic/vsprintf.c b/lib_generic/vsprintf.c index 767dde1ba7..3ab1f5cb07 100644 --- a/lib_generic/vsprintf.c +++ b/lib_generic/vsprintf.c @@ -21,6 +21,31 @@ extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]); #endif +#ifdef CONFIG_SYS_64BIT_VSPRINTF +# define NUM_TYPE long long +#else +# define NUM_TYPE long +#endif +#define noinline __attribute__((noinline)) + +#define do_div(n, base) ({ \ + unsigned int __res; \ + __res = ((unsigned NUM_TYPE) n) % base; \ + n = ((unsigned NUM_TYPE) n) / base; \ + __res; \ +}) + +const char hex_asc[] = "0123456789abcdef"; +#define hex_asc_lo(x) hex_asc[((x) & 0x0f)] +#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] + +static inline char *pack_hex_byte(char *buf, u8 byte) +{ + *buf++ = hex_asc_hi(byte); + *buf++ = hex_asc_lo(byte); + return buf; +} + unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base) { unsigned long result = 0,value; @@ -120,52 +145,132 @@ static int skip_atoi(const char **s) 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 NUM_TYPE 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 SPECIAL 32 /* 0x */ -#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */ +#define SMALL 32 /* Must be 32 == 0x20 */ +#define SPECIAL 64 /* 0x */ -#ifdef CONFIG_SYS_64BIT_VSPRINTF -#define do_div(n,base) ({ \ - unsigned int __res; \ - __res = ((unsigned long long) n) % base; \ - n = ((unsigned long long) n) / base; \ - __res; \ -}) -#else -#define do_div(n,base) ({ \ - int __res; \ - __res = ((unsigned long) n) % base; \ - n = ((unsigned long) n) / base; \ - __res; \ -}) -#endif - -#ifdef CONFIG_SYS_64BIT_VSPRINTF -static char * number(char * str, long long num, unsigned int base, int size, int precision ,int type) -#else -static char * number(char * str, long num, unsigned int base, int size, int precision ,int type) -#endif +static char *number(char *buf, unsigned NUM_TYPE num, int base, int size, int precision, int type) { - char c,sign,tmp[66]; - const char *digits="0123456789abcdefghijklmnopqrstuvwxyz"; + /* 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; - if (type & LARGE) - digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; + /* 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; - if (base < 2 || base > 36) - return 0; - c = (type & ZEROPAD) ? '0' : ' '; sign = 0; if (type & SIGN) { - if (num < 0) { + if ((signed NUM_TYPE) num < 0) { sign = '-'; - num = -num; + num = - (signed NUM_TYPE) num; size--; } else if (type & PLUS) { sign = '+'; @@ -175,68 +280,231 @@ static char * number(char * str, long num, unsigned int base, int size, int prec size--; } } - if (type & SPECIAL) { + if (need_pfx) { + size--; if (base == 16) - size -= 2; - else if (base == 8) size--; } + + /* generate full string in tmp[], in reverse order */ i = 0; if (num == 0) - tmp[i++]='0'; - else while (num != 0) - tmp[i++] = digits[do_div(num,base)]; + 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) - *str++ = ' '; + if (!(type & (ZEROPAD+LEFT))) + while(--size >= 0) + *buf++ = ' '; + /* sign */ if (sign) - *str++ = sign; - if (type & SPECIAL) { - if (base==8) - *str++ = '0'; - else if (base==16) { - *str++ = '0'; - *str++ = digits[33]; - } + *buf++ = sign; + /* "0x" / "0" prefix */ + if (need_pfx) { + *buf++ = '0'; + if (base == 16) + *buf++ = ('X' | locase); + } + /* zero or space padding */ + if (!(type & LEFT)) { + char c = (type & ZEROPAD) ? '0' : ' '; + while (--size >= 0) + *buf++ = c; } - if (!(type & LEFT)) - while (size-- > 0) - *str++ = c; - while (i < precision--) - *str++ = '0'; - while (i-- > 0) - *str++ = tmp[i]; - while (size-- > 0) - *str++ = ' '; - return str; + /* hmm even more zero padding? */ + while (i <= --precision) + *buf++ = '0'; + /* actual digits of result */ + while (--i >= 0) + *buf++ = tmp[i]; + /* trailing space padding */ + while (--size >= 0) + *buf++ = ' '; + return buf; } -/* Forward decl. needed for IP address printing stuff... */ -int sprintf(char * buf, const char *fmt, ...); +static char *string(char *buf, char *s, int field_width, int precision, int flags) +{ + int len, i; -int vsprintf(char *buf, const char *fmt, va_list args) + if (s == 0) + s = "<NULL>"; + + len = strnlen(s, precision); + + if (!(flags & LEFT)) + while (len < field_width--) + *buf++ = ' '; + for (i = 0; i < len; ++i) + *buf++ = *s++; + while (len < field_width--) + *buf++ = ' '; + return buf; +} + +#ifdef CONFIG_CMD_NET +static char *mac_address_string(char *buf, u8 *addr, int field_width, + int precision, int flags) { - int len; -#ifdef CONFIG_SYS_64BIT_VSPRINTF - unsigned long long num; -#else - unsigned long num; + char mac_addr[6 * 3]; /* (6 * 2 hex digits), 5 colons and trailing zero */ + char *p = mac_addr; + int i; + + for (i = 0; i < 6; i++) { + p = pack_hex_byte(p, addr[i]); + if (!(flags & SPECIAL) && i != 5) + *p++ = ':'; + } + *p = '\0'; + + return string(buf, mac_addr, field_width, precision, flags & ~SPECIAL); +} + +static char *ip6_addr_string(char *buf, u8 *addr, int field_width, + int precision, int flags) +{ + char ip6_addr[8 * 5]; /* (8 * 4 hex digits), 7 colons and trailing zero */ + char *p = ip6_addr; + int i; + + for (i = 0; i < 8; i++) { + p = pack_hex_byte(p, addr[2 * i]); + p = pack_hex_byte(p, addr[2 * i + 1]); + if (!(flags & SPECIAL) && i != 7) + *p++ = ':'; + } + *p = '\0'; + + return string(buf, ip6_addr, field_width, precision, flags & ~SPECIAL); +} + +static char *ip4_addr_string(char *buf, u8 *addr, int field_width, + int precision, int flags) +{ + char ip4_addr[4 * 4]; /* (4 * 3 decimal digits), 3 dots and trailing zero */ + char temp[3]; /* hold each IP quad in reverse order */ + char *p = ip4_addr; + int i, digits; + + for (i = 0; i < 4; i++) { + digits = put_dec_trunc(temp, addr[i]) - temp; + /* reverse the digits in the quad */ + while (digits--) + *p++ = temp[digits]; + if (i != 3) + *p++ = '.'; + } + *p = '\0'; + + return string(buf, ip4_addr, field_width, precision, flags & ~SPECIAL); +} #endif - int i, base; - char * str; - const char *s; + +/* + * 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: + * + * - 'M' For a 6-byte MAC address, it prints the address in the + * usual colon-separated hex notation + * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated + * decimal for v4 and colon separated network-order 16 bit hex for v6) + * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is + * currently the same + * + * 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, void *ptr, int field_width, int precision, int flags) +{ + if (!ptr) + return string(buf, "(null)", field_width, precision, flags); + +#ifdef CONFIG_CMD_NET + switch (*fmt) { + case 'm': + flags |= SPECIAL; + /* Fallthrough */ + case 'M': + return mac_address_string(buf, ptr, field_width, precision, flags); + case 'i': + flags |= SPECIAL; + /* Fallthrough */ + case 'I': + if (fmt[1] == '6') + return ip6_addr_string(buf, ptr, field_width, precision, flags); + if (fmt[1] == '4') + return ip4_addr_string(buf, ptr, field_width, precision, flags); + flags &= ~SPECIAL; + break; + } +#endif + flags |= SMALL; + if (field_width == -1) { + field_width = 2*sizeof(void *); + flags |= ZEROPAD; + } + return number(buf, (unsigned long) ptr, 16, field_width, precision, flags); +} + +/** + * 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 + * + * This function follows C99 vsprintf, 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 function returns the number of characters written + * into @buf. + * + * Call this function if you are already dealing with a va_list. + * You probably want sprintf() instead. + */ +int vsprintf(char *buf, const char *fmt, va_list args) +{ + unsigned NUM_TYPE num; + int base; + char *str; 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 'q' for integer fields */ + 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 */ + + str = buf; - for (str=buf ; *fmt ; ++fmt) { + for (; *fmt ; ++fmt) { if (*fmt != '%') { *str++ = *fmt; continue; @@ -252,7 +520,7 @@ int vsprintf(char *buf, const char *fmt, va_list args) case ' ': flags |= SPACE; goto repeat; case '#': flags |= SPECIAL; goto repeat; case '0': flags |= ZEROPAD; goto repeat; - } + } /* get field width */ field_width = -1; @@ -286,14 +554,13 @@ int vsprintf(char *buf, const char *fmt, va_list args) /* get the conversion qualifier */ qualifier = -1; if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || - *fmt == 'Z' || *fmt == 'z' || *fmt == 't' || - *fmt == 'q' ) { + *fmt == 'Z' || *fmt == 'z' || *fmt == 't') { qualifier = *fmt; - if (qualifier == 'l' && *(fmt+1) == 'l') { - qualifier = 'q'; + ++fmt; + if (qualifier == 'l' && *fmt == 'l') { + qualifier = 'L'; ++fmt; } - ++fmt; } /* default base */ @@ -310,32 +577,18 @@ int vsprintf(char *buf, const char *fmt, va_list args) continue; case 's': - s = va_arg(args, char *); - if (!s) - s = "<NULL>"; - - len = strnlen(s, precision); - - if (!(flags & LEFT)) - while (len < field_width--) - *str++ = ' '; - for (i = 0; i < len; ++i) - *str++ = *s++; - while (len < field_width--) - *str++ = ' '; + str = string(str, va_arg(args, char *), field_width, precision, flags); continue; case 'p': - if (field_width == -1) { - field_width = 2*sizeof(void *); - flags |= ZEROPAD; - } - str = number(str, - (unsigned long) va_arg(args, void *), 16, - field_width, precision, flags); + str = pointer(fmt+1, str, + va_arg(args, void *), + field_width, precision, flags); + /* Skip all alphanumeric pointer suffixes */ + while (isalnum(fmt[1])) + fmt++; continue; - case 'n': if (qualifier == 'l') { long * ip = va_arg(args, long *); @@ -355,9 +608,9 @@ int vsprintf(char *buf, const char *fmt, va_list args) base = 8; break; - case 'X': - flags |= LARGE; case 'x': + flags |= SMALL; + case 'X': base = 16; break; @@ -376,12 +629,14 @@ int vsprintf(char *buf, const char *fmt, va_list args) continue; } #ifdef CONFIG_SYS_64BIT_VSPRINTF - if (qualifier == 'q') /* "quad" for 64 bit variables */ + if (qualifier == 'L') /* "quad" for 64 bit variables */ num = va_arg(args, unsigned long long); else #endif 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') { @@ -389,17 +644,29 @@ int vsprintf(char *buf, const char *fmt, va_list args) } else if (qualifier == 'h') { num = (unsigned short) va_arg(args, int); if (flags & SIGN) - num = (short) num; - } else if (flags & SIGN) - num = va_arg(args, int); - else + num = (signed short) num; + } else { num = va_arg(args, unsigned int); + if (flags & SIGN) + num = (signed int) num; + } str = number(str, num, base, field_width, precision, flags); } *str = '\0'; return str-buf; } +/** + * 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. + * + * See the vsprintf() documentation for format string extensions over C99. + */ int sprintf(char * buf, const char *fmt, ...) { va_list args; |