kservice.c.svn-base

RT-Thread是发展中的下一代微内核嵌入式实时操作系统

/*
 * File      : kservice.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006, RT-Thread Development Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://openlab.rt-thread.com/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-03-16     Bernard      the first version
 * 2006-05-25     Bernard      rewrite vsprintf
 * 2006-08-10     Bernard      add rt_show_version
 */

#include <rtthread.h>
#include <rthw.h>

/**
 * @addtogroup KernelService
 */
/*@{*/

/**
 * This function will set the content of memory to specified value
 *
 * @param s the address of source memory
 * @param c the value shall be set in content
 * @param count the copied length
 *
 * @return the address of source memory
 *
 */
void *rt_memset(void * s, int c, rt_uint16 count)
{
    char *xs = (char *) s;

    while (count--)
        *xs++ = c;

    return s;
}

/**
 * This function will copy memory content from source address to destination
 * address.
 *
 * @param dest the address of destination memory
 * @param src  the address of source memory
 * @param count the copied length
 *
 * @return the address of destination memory
 *
 */
void *rt_memcpy(void *dest, const void *src, rt_uint16 count)
{
    char *tmp = (char *) dest, *s = (char *) src;

    while (count--)
        *tmp++ = *s++;

    return dest;
}

/**
 * This function will compare two strings with specified maximum length
 *
 * @param cs the string to be compared
 * @param ct the string to be compared
 * @param count the maximum compare length
 *
 * @return the result
 */
rt_uint16 rt_strncmp(const char * cs, const char * ct, rt_uint16 count)
{
    register signed char __res = 0;

    while (count)
    {
        if ((__res = *cs - *ct++) != 0 || !*cs++)
            break;
        count--;
    }

    return __res;
}

/**
 * This function will return the length of a string, which terminate will 
 * null character.
 *
 * @param s the string
 *
 * @return the length of string
 */
rt_uint16 rt_strlen(const char *s)
{
    const char *sc;

    for (sc = s; *sc != '\0'; ++sc) /* nothing */
        ;

    return sc - s;
}

/**
 * This function will show the version of rt-thread rtos
 */
void rt_show_version(void)
{
	rt_kprintf(" \\ | /\n");
	rt_kprintf("- RT - Thread Operating System\n");
	rt_kprintf(" / | \\ 0.%d.%d build %s\n", RT_VERSION, RT_SUBVERSION, __DATE__);
	rt_kprintf(" 2006 Copyright by rt-thread team\n");
}

static char rt_log_buf[RT_CONSOLEBUF_SIZE]; /* Message log buffer */

/* private function */
#define isdigit(c)  ((unsigned)((c) - '0') < 10)

rt_inline rt_int32 divide(rt_int32 *n, rt_int32 base)
{
    rt_int32 res;

	/* optimized for processor which does not support divide instructions. */
    if (base == 10)
    {
        res = ((rt_uint32)*n) % 10U;
        *n = ((rt_uint32)*n) / 10U;
    }
    else
    {
        res = ((rt_uint32)*n) % 16U;
        *n = ((rt_uint32)*n) / 16U;
    }

    return res;
}

rt_inline int skip_atoi(const char **s)
{
    register int i=0;
    while (isdigit(**s)) i = i*10 + *((*s)++) - '0';

    return i;
}

#define ZEROPAD 	(1 << 0)	/* pad with zero */
#define SIGN 		(1 << 1)	/* unsigned/signed long */
#define PLUS 		(1 << 2)	/* show plus */
#define SPACE 		(1 << 3)	/* space if plus */
#define LEFT 		(1 << 4)	/* left justified */
#define SPECIAL 	(1 << 5)	/* 0x */
#define LARGE		(1 << 6)	/* use 'ABCDEF' instead of 'abcdef' */

#ifdef RT_PRINTF_PRECISION
static char *print_number(char * buf, char * end, long num, int base, int s, int precision, int type)
#else
static char *print_number(char * buf, char * end, long num, int base, int s, int type)
#endif
{
    char c, sign;
#ifdef RT_PRINTF_LONGLONG
    char tmp[32];
#else
	char tmp[16];
#endif
    const char *digits;
    static const char small_digits[] = "0123456789abcdef";
    static const char large_digits[] = "0123456789ABCDEF";
    register int i;
    register int size;

	size = s;

    digits = (type & LARGE) ? large_digits : small_digits;
    if (type & LEFT) type &= ~ZEROPAD;

    c = (type & ZEROPAD) ? '0' : ' ';
    
    /* get sign */
    sign = 0;
    if (type & SIGN)
    {
        if (num < 0)
        {
            sign = '-';
            num = -num;
        }
        else if (type & PLUS) sign = '+';
        else if (type & SPACE) sign = ' ';
    }

#ifdef RT_PRINTF_SPECIAL
    if (type & SPECIAL)
    {
        if (base == 16) size -= 2;
        else if (base == 8) size--;
    }
#endif

    i = 0;
    if (num == 0) tmp[i++]='0';
    else
    {
        while (num != 0) tmp[i++] = digits[divide(&num, base)];
    }

#ifdef RT_PRINTF_PRECISION
    if (i > precision) precision = i;
    size -= precision;
#else
	size -= i;
#endif

    if (!(type&(ZEROPAD | LEFT)))
    {
        while(size-->0)
        {
            if (buf <= end) *buf = ' ';
            ++buf;
        }
    }

    if (sign)
    {
        if (buf <= end)
        {
			*buf = sign;
			--size;
		}
        ++buf;
    }

#ifdef RT_PRINTF_SPECIAL
    if (type & SPECIAL)
    {
        if (base==8)
        {
            if (buf <= end) *buf = '0';
            ++buf;
        }
        else if (base==16)
        {
            if (buf <= end) *buf = '0';
            ++buf;
            if (buf <= end)
            {
				*buf = type & LARGE? 'X' : 'x';
			}
            ++buf;
        }
    }
#endif

	/* no align to the left */
    if (!(type & LEFT))
    {
        while (size-- > 0)
        {
            if (buf <= end) *buf = c;
            ++buf;
        }
    }

#ifdef RT_PRINTF_PRECISION
    while (i < precision--)
    {
        if (buf <= end) *buf = '0';
        ++buf;
    }
#endif

	/* put number in the temporary buffer */
    while (i-- > 0)
    {
        if (buf <= end) *buf = tmp[i];
        ++buf;
    }

    while (size-- > 0)
    {
        if (buf <= end) *buf = ' ';
        ++buf;
    }

    return buf;
}

static rt_int32 vsnprintf(char *buf, rt_size_t size, const char *fmt, va_list args)
{
#ifdef RT_PRINTF_LONGLONG
    unsigned long long num;
#else
	rt_uint32 num;
#endif
    int i, len;
    char *str, *end, c;
    const char *s;

	rt_uint8 base;			/* the base of number */
    rt_uint8 flags;			/* flags to print number */
    rt_uint8 qualifier;		/* 'h', 'l', or 'L' for integer fields */
    rt_int32 field_width;	/* width of output field */

#ifdef RT_PRINTF_PRECISION
    int precision;		/* min. # of digits for integers and max for a string */
#endif

    str = buf;
    end = buf + size - 1;

    for (; *fmt ; ++fmt)
    {
        if (*fmt != '%')
        {
            if (str <= end) *str = *fmt;
            ++str;
            continue;
        }
        
        /* process flags */
        flags = 0;
        
		while(1)
		{
			/* skips the first '%' also */
			++fmt;
			if (*fmt == '-') flags |= LEFT;
			else if (*fmt == '+') flags |= PLUS;
			else if (*fmt == ' ') flags |= SPACE;
			else if (*fmt == '#') flags |= SPECIAL;
			else if (*fmt == '0') flags |= ZEROPAD;
			else break;
		}

        /* 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;
            }
        }

#ifdef RT_PRINTF_PRECISION
        /* 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;
        }
#endif
        /* get the conversion qualifier */
        qualifier = 0;
        if (*fmt == 'h' || *fmt == 'l'
#ifdef RT_PRINTF_LONGLONG
		|| *fmt == 'L'
#endif
		)
        {
            qualifier = *fmt;
            ++fmt;
#ifdef RT_PRINTF_LONGLONG            
            if (qualifier == 'l' && *fmt == 'l')
            {
                qualifier = 'L';
                ++fmt;
            }
#endif
        }
        
        /* the default base */
        base = 10;
        
        switch (*fmt)
        {
		case 'c':
            if (!(flags & LEFT))
            {
                while (--field_width > 0)
                {
                    if (str <= end) *str = ' ';
                    ++str;
                }
            }
            
            /* get character */
            c = (rt_uint8) va_arg(args, int);
            if (str <= end) *str = c;
            ++str;
            
            /* put width */
            while (--field_width > 0)
            {
                if (str <= end) *str = ' ';
                ++str;
            }
            continue;
            
		case 's':
            s = va_arg(args, char *);
            if (!s) s = "(NULL)";
            
			len = rt_strlen(s);
#ifdef RT_PRINTF_PRECISION
			if (precision > 0 && len > precision) len = precision;
#endif
			
            if (!(flags & LEFT))
            {
                while (len < field_width--)
                {
                    if (str <= end) *str = ' ';
                    ++str;
                }
            }
            
            for (i = 0; i < len; ++i)
            {
                if (str <= end) *str = *s;
                ++str;
                ++s;
            }
            
            while (len < field_width--)
            {
                if (str <= end) *str = ' ';
                ++str;
            }
            continue;
            
		case 'p':
            if (field_width == -1)
            {
                field_width = sizeof(void *) << 1;
                flags |= ZEROPAD;
            }
#ifdef RT_PRINTF_PRECISION
            str = print_number(str, end,
                         (long) va_arg(args, void *),
                         16, field_width, precision, flags);
#else
            str = print_number(str, end,
                         (long) va_arg(args, void *),
                         16, field_width, flags);
#endif
            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 |= LARGE;
		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;
        }

#ifdef RT_PRINTF_LONGLONG
        if (qualifier == 'L') num = va_arg(args, long long);
        else if (qualifier == 'l')
#else
        if (qualifier == 'l')
#endif
        {
            num = va_arg(args, rt_uint32);
            if (flags & SIGN) num = (rt_int32) num;
        }
        else if (qualifier == 'h')
        {
            num = (rt_uint16) va_arg(args, rt_int32);
            if (flags & SIGN) num = (rt_int16) num;
        }
        else
        {
            num = va_arg(args, rt_uint32);
            if (flags & SIGN) num = (rt_int32) num;
        }
#ifdef RT_PRINTF_PRECISION
        str = print_number(str, end, num, base, field_width, precision, flags);
#else
        str = print_number(str, end, num, base, field_width, flags);
#endif
    }

    if (str <= end) *str = '\0';
    else *end = '\0';

    /* the trailing null byte doesn't count towards the total
    * ++str;
    */
    return str-buf;
}

/**
 * This function will fill a formatted string to buffer
 *
 * @param buf the buffer to save formatted string
 * @param size the buffer size
 * @param fmt the format
 */
void rt_snprintf(char *buf, rt_size_t size, const char *fmt, ...)
{
    va_list args;

    va_start(args, fmt);
    vsnprintf(buf, size, fmt, args);
    va_end(args);
}

/**
 * This function will print a formatted string on system console
 *
 * @param fmt the format
 */
void rt_kprintf(const char *fmt, ...)
{
    va_list args;
    va_start(args, fmt);

    vsnprintf(rt_log_buf, sizeof(rt_log_buf), fmt, args);
    rt_console_puts(rt_log_buf);

    va_end(args);
}

/*@}*/