conv.c

用C语言实现的字符型的菜单界面

/*----------------------------------------------------------------------------*
 * 功    能: 字符串转换操作库.						      *
 * 版    本: 1.00							      *
 * 运行环境: SCO UNIX V3.2.4 以上版本.					      *
 * 历史记录: 日      期	作  者	备    注				      *
 *----------------------------------------------------------------------------*
 *           1999/10/20	赖正兴	创建				      	      *
 *----------------------------------------------------------------------------*
 * All rights reserved. Copyright (C) 1999-20001.			      *
 *----------------------------------------------------------------------------*/

/*
  Includes
*/
#include <port.h>
#include <string.h>


/*
  Macros
*/


/*
  Local types
*/


/*
  Exported variables
*/


/*
  Local variables
*/


/*
  Macro functions
*/
#define hex(x)		((x)<=9 ? ((x)+'0') : ((x)+('A'-0x0a)) )


/*
  Functions
*/


static u_1by_t	char_ascii_to_hex( u_1by_t ascii)
{
    u_1by_t	val;

    val = ascii;
    if( (val>='0') && (val<='9'))
    {
      val = val & 0x0f;
    }
    else
    if( (val>='a') && (val<='f'))
    {
      val = val - 'a' + 0x0a;
    }
    else
    if( (val>='A') && (val<='F'))
    {
      val = val - 'A' + 0x0a;
    }
    else
    {
      val = 0;
    }
    return( val);
} /* char_ascii_to_hex */


static void	convert_to_leading_spaces( u_1by_t *buf, u_2by_t len)
{
  u_2by_t	i;

  i = 0;
  while( (i<len) and (*buf == '0'))
  {
    *buf = ' ';				/* change leading zeroes to spaces. */
    buf++;
    i++;
  }
  buf--;				/* got to last byte */

  if( (i==len) and (*buf==' '))		/* if all spaces */
  {
    *buf = '0';				/* change last space back to zero */
  }
}


void	hex_to_ascii( u_1by_t *ascii_buf,	u_1by_t *hex_buf,	u_2by_t ascii_len)
{
  u_2by_t	i;
  u_1by_t	val;

  for( i=0; i<ascii_len; i++)
  {
    if( even( i))
    {
      val = *hex_buf;
      *ascii_buf = hex( val >> 4);
      ascii_buf++;
    }
    else
    {
      *ascii_buf = hex( val & 0x0f);
      ascii_buf++;
      hex_buf++;
    }
  }

  convert_to_leading_spaces( ascii_buf - ascii_len, ascii_len);
} /* hex_to_ascii */


void	ascii_to_hex( u_1by_t *hex_buf,	u_1by_t *ascii_buf,	u_2by_t ascii_len)
{
  u_2by_t	i, len;

  len = (ascii_len+1) / 2;
  for( i=0; i<len; i++)
  {
    *hex_buf  = char_ascii_to_hex( *ascii_buf) << 4;	/* high nibble */
    ascii_buf++;
    *hex_buf |= char_ascii_to_hex( *ascii_buf);		/* low  nibble */
    ascii_buf++;
    hex_buf++;
  }
  if( odd( ascii_len))
  {
    hex_buf--;
    *hex_buf &= 0xf0;	/* odd lengths have the extra digit set to 0 */
  }
} /* ascii_to_hex */


u_2by_t	bcd_to_bin(	u_1by_t *bcd_buf,	u_2by_t bcd_len)
{
  u_2by_t	rc;
  u_2by_t	i;
  u_1by_t	val;

  rc = 0;
  for( i=0; i<bcd_len; i++)
  {
    val = *bcd_buf;
    rc = rc*10 + (val >> 4);
    rc = rc*10 + (val & 0x0f);
    bcd_buf++;
  }
  return( rc);
} /* bcd_to_bin */


void	bin_to_bcd(	u_1by_t *bcd_buf,	u_2by_t bin,	u_2by_t bcd_len)
{
  u_2by_t	i;
  u_2by_t	multiple, remainder;

  bcd_buf += bcd_len - 1;
  for( i=bcd_len; i>0; i--)
  {
    multiple  = bin / 10;
    remainder = bin - (multiple * 10);
    bin = multiple;
    *bcd_buf  = remainder;

    multiple  = bin / 10;
    remainder = bin - (multiple * 10);
    bin = multiple;
    *bcd_buf |= remainder << 4;

    bcd_buf--;
  }
} /* bin_to_bcd */


u_2by_t	ascii_to_bin(	u_1by_t *ascii_buf,	u_2by_t ascii_len)
{
  u_2by_t	rc;
  u_2by_t	i;

  rc = 0;
  for( i=0; i<ascii_len; i++)
  {
    rc = rc*10 + char_ascii_to_hex( *ascii_buf);
    ascii_buf++;
  }
  return( rc);
} /* ascii_to_bin */


void	bin_to_ascii(	u_1by_t *ascii_buf,	u_2by_t bin,	u_2by_t ascii_len)
{
  u_2by_t	i;
  u_2by_t	multiple, remainder;

  ascii_buf += ascii_len - 1;
  for( i=ascii_len; i>0; i--)
  {
    multiple  = bin / 10;
    remainder = bin - (multiple * 10);
    bin = multiple;
    *ascii_buf  = hex( remainder);
    ascii_buf--;
  }

  ascii_buf++;		/* go to first byte */
  convert_to_leading_spaces( ascii_buf, ascii_len);
} /* bin_to_ascii */

/*----------------------------------------------------------------------------*
 * FUNCTION: ascii码字符串转成bcd码字符串.
 * Argument:
 *           char *bcd_buf - bcd码字符串.
 *           char *asc_buf - asc码字符串.
 *           int asc_len - asc码字符串的长度.
 * Return  : 
 *           TRUE - 转换成功.                                  
 *           FALSE - 转换失败.                                  
 * Example : "1234567a"  ==> 0x12 0x34 0x56 0x7a
 *           "1234567"   ==> 0x12 0x34 0x56 0x7f
 *----------------------------------------------------------------------------*/
ascii_to_bcd(char *bcd_buf,const char *asc_buf,int asc_len)
{
	int i,bcd_len;
	char ch,ch2,databuf[1025];

	if(asc_len > 1024) return(FALSE);
	bcd_len = (asc_len+1)/2;

	memcpy(databuf,asc_buf,asc_len);
	databuf[asc_len]='\0';

	while(strlen(databuf) < asc_len)
		strcat(databuf,"0");

	for(i=0;i<bcd_len;i++)
	{
		ch =my_tolower(databuf[i*2]);
		ch2=my_tolower(databuf[i*2+1]);

		if(ch>='a' && ch<='z')
		{
			ch=(ch >'f') ? (0) : (ch-'a'+10);
		}
		else
		{
			ch=(ch<'0' || ch>'9') ? (0):(ch-'0');
		}
		if(ch2>='a' && ch2<='z')
		{
			ch2=(ch2 >'f') ? (0) : (ch2-'a'+10);
		}
		else
		{
			ch2=(ch2<'0' || ch2>'9') ? (0):(ch2-'0');
		}
		bcd_buf[i]=ch;
		bcd_buf[i]<<=4;
		bcd_buf[i]+=ch2;
	}
	return(TRUE);
}
/*----------------------------------------------------------------------------*
 * FUNCTION: ascii码字符串转成ascii码字符串(不补空格).
 * Argument:
 *           char *asc_des - asc码字符串.
 *           char *asc_src - asc码字符串.
 *           int asc_len - asc码字符串的长度.
 * Return  : 
 *           TRUE - 转换成功.                                  
 * Example : "12345678"  ==> "12345678" 
 *           "123456"    ==> "123456  "
 *----------------------------------------------------------------------------*/
ascii_to_ascii(char *asc_des,char *asc_src,int asc_len)
{
	int i;

	memcpy(asc_des,asc_src,asc_len);
	i=strlen(asc_src);
	if(i < asc_len)
		memset(asc_des+i,' ',asc_len-i);
	asc_des[asc_len]='\0';

	return(TRUE);
}

/*----------------------------------------------------------------------------*
 * FUNCTION: bcd码字符串转成ascii码字符串.
 * Argument:
 *           char *asc_buf - asc码字符串.
 *           char *bcd_buf - bcd码字符串.
 *           int bcd_len - bcd码字符串的长度.
 * Return  : 
 *           TRUE - 转换成功.                                  
 * Example : "\x12\x34\x56\x7a" ==> "1234567a"
 *----------------------------------------------------------------------------*/
bcd_to_ascii(char *asc_buf,char *bcd_buf,int bcd_len)
{
	int i;

	for(i=0;i<bcd_len;i++)
	{
		sprintf(asc_buf[2*i],"%02x",bcd_buf[i]);
	}
	return(TRUE);
}
/* End of conv.c */