diff options
Diffstat (limited to 'kernel/arch/x86/boot/printf.c')
| -rw-r--r-- | kernel/arch/x86/boot/printf.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/kernel/arch/x86/boot/printf.c b/kernel/arch/x86/boot/printf.c new file mode 100644 index 000000000..565083c16 --- /dev/null +++ b/kernel/arch/x86/boot/printf.c @@ -0,0 +1,309 @@ +/* -*- linux-c -*- ------------------------------------------------------- * + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright 2007 rPath, Inc. - All Rights Reserved + * + * This file is part of the Linux kernel, and is made available under + * the terms of the GNU General Public License version 2. + * + * ----------------------------------------------------------------------- */ + +/* + * Oh, it's a waste of space, but oh-so-yummy for debugging. This + * version of printf() does not include 64-bit support. "Live with + * it." + * + */ + +#include "boot.h" + +static int skip_atoi(const char **s) +{ + int i = 0; + + while (isdigit(**s)) + i = i * 10 + *((*s)++) - '0'; + return i; +} + +#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 */ + +#define __do_div(n, base) ({ \ +int __res; \ +__res = ((unsigned long) n) % (unsigned) base; \ +n = ((unsigned long) n) / (unsigned) base; \ +__res; }) + +static char *number(char *str, 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 c, sign, locase; + 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; + if (base < 2 || base > 16) + return NULL; + c = (type & ZEROPAD) ? '0' : ' '; + sign = 0; + if (type & SIGN) { + if (num < 0) { + sign = '-'; + num = -num; + size--; + } else if (type & PLUS) { + sign = '+'; + size--; + } else if (type & SPACE) { + sign = ' '; + size--; + } + } + if (type & SPECIAL) { + if (base == 16) + size -= 2; + else if (base == 8) + size--; + } + i = 0; + if (num == 0) + tmp[i++] = '0'; + else + while (num != 0) + tmp[i++] = (digits[__do_div(num, base)] | locase); + if (i > precision) + precision = i; + size -= precision; + if (!(type & (ZEROPAD + LEFT))) + while (size-- > 0) + *str++ = ' '; + if (sign) + *str++ = sign; + if (type & SPECIAL) { + if (base == 8) + *str++ = '0'; + else if (base == 16) { + *str++ = '0'; + *str++ = ('X' | locase); + } + } + 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; +} + +int vsprintf(char *buf, const char *fmt, va_list args) +{ + int len; + unsigned long num; + int i, base; + char *str; + const char *s; + + 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 */ + + for (str = buf; *fmt; ++fmt) { + if (*fmt != '%') { + *str++ = *fmt; + 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') { + qualifier = *fmt; + ++fmt; + } + + /* default base */ + base = 10; + + switch (*fmt) { + case 'c': + if (!(flags & LEFT)) + while (--field_width > 0) + *str++ = ' '; + *str++ = (unsigned char)va_arg(args, int); + while (--field_width > 0) + *str++ = ' '; + continue; + + case 's': + s = va_arg(args, char *); + 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++ = ' '; + 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); + continue; + + case 'n': + if (qualifier == 'l') { + long *ip = va_arg(args, long *); + *ip = (str - buf); + } else { + int *ip = va_arg(args, int *); + *ip = (str - buf); + } + continue; + + case '%': + *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: + *str++ = '%'; + if (*fmt) + *str++ = *fmt; + else + --fmt; + continue; + } + if (qualifier == 'l') + num = va_arg(args, unsigned long); + 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 = va_arg(args, unsigned int); + str = number(str, num, base, field_width, precision, flags); + } + *str = '\0'; + return str - buf; +} + +int sprintf(char *buf, const char *fmt, ...) +{ + va_list args; + int i; + + va_start(args, fmt); + i = vsprintf(buf, fmt, args); + va_end(args); + return i; +} + +int printf(const char *fmt, ...) +{ + char printf_buf[1024]; + va_list args; + int printed; + + va_start(args, fmt); + printed = vsprintf(printf_buf, fmt, args); + va_end(args); + + puts(printf_buf); + + return printed; +} |