fsutils.c

嵌入式系统中文件系统源代码

/****************************************************************
File Name: FSUTILS.C						*
*****************************************************************
Last Modified Date: 2001/04/17
Compiler : GNU Cross-compiler/SDS
Platform : X86 protection mode, MIPS, Dragonball
Usage :
	Utility functions for file system, including my
	replacement functions for ANSI-C functions.
****************************************************************/
#include <sys/syscall.h>

//#include <ansi_c/stdio.h>
/**** modified by chilong 8/23/2001 ****/
#include <stdio.h>
/**** modified by chilong 8/23/2001 ****/

#include <kernel/general.h>
//#include "../rDebug/include/rdebug.h"
#include "../include/FileSys.h"


extern void printString(char *string);


/*************************************************************
Function: myStrLen
Description:
	get the length of a string
Input:
	src - the source string with a mix of single-byte and
	      double-byte chars
Output:
**************************************************************/
int myStrLen(unsigned char *src)
{
  int length = 0;

  while (*src != '\0')
  {
	length++;
	src++;
  }
  return length;
}



/**************************************************************
Function: myMemSet
Description:
	set every byte in the destination buffer to a value
Input:
	dest - the destination buffer
	value - the target value
	length - the length of the buffer in bytes
**************************************************************/
void *myMemSet(void *dest, char value, unsigned long length)
{
  char *dp = (char *)dest;

  while (length !=0)
  {
	*dp++ = value;
	length--;
  }

  return(dest);
}



/**************************************************************
Function: myMemCpy
Description:
	copy the content of one buffer to another buffer
Input:
	out - the source
	in - the destination
	length - amount of data to be copied in bytes
**************************************************************/
void *myMemCpy(void *out, const void *in, unsigned long length)
{
  char *dst = (char *)out;
  char *src = (char *)in;
  void *save = (char *)out;

  while (length--)
  {
	*dst++ = *src++;
  }

  return save;
}



/**************************************************************
Function: myStrCpy
Description:
	copy the content of a string to another buffer
Input:
	to - the source string
	from - the destination string
**************************************************************/
char *myStrCpy(char *to, const char *from)
{
  char *p = to;

  while (*p++ = *from++)
	;

  return(to);
}



/*************************************************************
Function: endian_little2local_short
Description:
	Convert a short integer from little endian to the
	endian used by the current CPU
Input:
	little - the value in little endian
	local - the short integer in the endian used by the local CPU
**************************************************************/
void endian_little2local_short(unsigned char *little, unsigned short *local)
{
  *local = (unsigned short)little[1];
  *local = (*local << 8) | little[0];

  return;
}



/*************************************************************
Function: endian_local2little_short
Description:
	Convert a short integer from the endian used by the
	current CPU to little endian
Input:
	local - the short integer in the endian used by the local CPU
	little - the resulting value in little endian
**************************************************************/
void endian_local2little_short(unsigned short *local, unsigned char *little)
{
  little[1] = (*local >> 8);
  little[0] = *local & 0x00FF;

  return;
}



/*************************************************************
Function: endian_little2local_long
Description:
	Convert a long integer from little endian to the
	endian used by the current CPU
Input:
	little - the value in little endian
	local - the long integer in the endian used by the local CPU
**************************************************************/
void endian_little2local_long(unsigned char *little, unsigned long *local)
{
  *local = (unsigned short)little[3];
  *local = (*local << 8) | little[2];
  *local = (*local << 8) | little[1];
  *local = (*local << 8) | little[0];

  return;
}



/*************************************************************
Function: endian_local2little_long
Description:
	Convert a long integer from the endian used by the
	current CPU to little endian
Input:
	local - the long integer in the endian used by the local CPU
	little - the resulting value in little endian
**************************************************************/
void endian_local2little_long(unsigned long *local, unsigned char *little)
{
  little[3] = (unsigned char)((*local >> 24) & 0x000000FF);
  little[2] = (unsigned char)((*local >> 16) & 0x000000FF);
  little[1] = (unsigned char)((*local >> 8) & 0x000000FF);
  little[0] = (unsigned char)(*local & 0x000000FF);

  return;
}



/*************************************************************
Function: toUpperCase
Description:
	Converts all lowercase char in a string to uppercase.
Input:
	string - target string
Output:
	string - in uppercase
Note:
	The original string with lowercase char is destroyed
	after this function.
**************************************************************/
void toUpperCase(unsigned char *string)
{
  while (*string != '\0')
  {
	if (*string < 0x80)
	{
		if ((*string >= 'a') && (*string <= 'z'))
			*string -= (char)('a' - 'A');
		string++;	
	}
	else
	{
		string++;
		if (*string == '\0')
			return;
		else
			string++;
	}
  }
}



/*************************************************************
Function: iCompareChar
Description:
	Case-insensitive comparison of 2 characters
Input:
	char1, char2 - the two chars to be compared
Output:
	1	match
	0	unmatch
**************************************************************/
#if 0//Kevin
int iCompareChar(unsigned char char1, unsigned char char2)
{
  if (char1 >= 'a' && char1 <= 'z')
	char1 -= ('a' - 'A');
  if (char2 >= 'a' && char2 <= 'z')
	char2 -= ('a' - 'A');
  if (char1 == char2)
	return 1;
  else
	return 0;
}
#endif


/*************************************************************
Function: timeConvert
Description:
	convert file's date and time to time in seconds
Input:
	fDate - file date
	fTime - file time
	timeInSec - the resulting time in seconds
Output:
	NONE
**************************************************************/
void timeConvert(unsigned short fDate, unsigned short fTime, unsigned long *timeInSec)
{
  int tm_sec;
  int tm_min;
  int tm_hour;
  int tm_mday;
  int tm_mon;
  int tm_year;
  unsigned int days = 0;

  //  16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1  
  //   h  h  h  h  h  m  m m m m m s s s s s	 

  //  16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
  //   y  y  y  y  y  y  y m m m m d d d d d	 

  tm_sec = (fTime & 0x001F) * 2;
  tm_min = (fTime & 0x07E0) >> 5;
  tm_hour = (fTime & 0xf800) >> 11;

  tm_mday = (fDate & 0x001F);

  /* because the available value of month is 0~6 */
  tm_mon = ((fDate & 0x01E0) >> 5);

  /* in C, year base is 1900 , but in TICKERS base is 1990 and in fat12 year base is 1980 */
  tm_year = ((fDate & 0xFE00) >> 9) + 90;

  *timeInSec = tm_sec + tm_min * 60 + tm_hour * 3600;

  days = (tm_year - 70) / 4;
  if (tm_year >= 100)
	days--;
  days += ((tm_year - 70) * 365);
  tm_year += 1900;
  days += ((tm_mon * 3057 - 3007) / 100);
  if (tm_mon > 2)
  {
	if (tm_year % 400 == 0 || (tm_year % 4 == 0 && tm_year % 100 != 0))
		days--;
	else
		days -= 2;
  }
  days += tm_mday;

  *timeInSec += days * 3600 * 24;

  return;
}



/*************************************************************
Function: myPrintInt
Description:
	Similar to printInt() but without going to the next line
Input:
	number - the number to be printed
	type - type of printing
**************************************************************/
void myPrintInt(unsigned long number, int type)
{
  char string[20];

  intToString((unsigned int)number, string, type);
  printString(string);
}