findx.c

嵌入式系统中文件系统源代码

			// fill in the ffblk structure
			ffres->ff_reserved = (long)ffInfo;
			ffres->ff_attrib = curEntry->attribute;
			ffres->ff_ftime = curEntry->time;
			ffres->ff_fdate = curEntry->date;
			ffres->ff_fsize = curEntry->fsize;
			ffres->ff_drive = RAMDISK_ID;
			// copy the name from dir entry to result
			i = 0;
			
			// modified by chilong 01/29/2002
			//while (curEntry->name[i] != '\0')
			while(curEntry->name[i] != '\0' && i < RD_FNAME_LEN)
			{
				ffres->ff_name[i] = curEntry->name[i];
				i++;
			}
			ffres->ff_name[i] = '\0';

#ifdef CURRENT_DIR_ENABLE
			ap_free(completeName);
#endif

			return 0;
		} // if loop status
		// not found, try next entry
		curEntry = (struct directory *)((unsigned long)curEntry + dirSize);
	} // for loop i

	// not found in this cluster, try next cluster in the chain
	curBlock = (struct diskBlock *)curBlock->nextBlock;
  }

  // all clusters in the chain have been searched, file not found
#ifdef CURRENT_DIR_ENABLE
  ap_free(completeName);
#endif

  ffres->ff_reserved = 0;

  RDerrno = ERROR_FILE_NOT_EXIST;
  return -1;
}



/*************************************************************
Function : RD_findnext
Description:
	find the next file that match the requirement
Input:
	ffres - a structure to hold the results of the search
Output:
	0	if a match has been found
	-1	if the searching failed

Note:
	There is a hidden attribute in [attrib]. If the highest
	bit in [attrib] is 0, only directories will be found
	if DA_DIR is set. If the highest bit in [attrib] is 1,
	both files and directories will be found if DA_DIR is
	set.
	
**************************************************************/
int RD_findnext(struct ffblk *ffres)
{
  int status;

  RDerrno = 0;

  if (InitRD == FALSE)
  {
	RDerrno = ERROR_FILE_SYSTEM_NOT_INIT;
	return -1;
  }

  if (ffres->ff_reserved == 0)
  {
	RDerrno = ERROR_FILE_NOT_EXIST;
	return -1;
  }

  if (ffres->ff_drive != RAMDISK_ID)
  {
	RDerrno = ERROR_INVALID_DEVICE;
	return -1;
  }

  sc_waitSemaphore(RD_SemaphoreID);

  status = RD_findnext_r(ffres);

  sc_signalSemaphore(RD_SemaphoreID);

  return status;
}


int RD_findnext_r(struct ffblk *ffres)
{
  struct ffInternal *ffInfo;	/* internal information for findnext */
  struct diskBlock *curBlock;
  struct directory *curEntry;
  long dirSize;
  long i;
  int nThEntry;			/* the n-th entry in root block */

  // get the pointer to the internal filefind structure
  ffInfo = (struct ffInternal *)ffres->ff_reserved;

  // start searching from this cluster
  curBlock = ffInfo->block;
  nThEntry = (int)ffInfo->nThEntry;

  dirSize = sizeof(struct directory);

  while (curBlock != NULL)
  {
	curEntry = (struct directory *)((unsigned long)curBlock + sizeof(struct diskBlock) + (nThEntry + 1) * dirSize);

	// compare entry by entry in the sector
	for (i = (nThEntry + 1) * dirSize; i < DIR_BLOCK_SIZE; i+= dirSize)
	{
		// this entry and every following entry are empty => not found
		if (curEntry->name[0] == '\0')
		{
			RDerrno = ERROR_FILE_NOT_EXIST;
			return -1;
		}

		// skip this entry if it an deleted entry
		if (curEntry->name[0] == DELETED_ENTRY)
		{
			curEntry = (struct directory *)((unsigned long)curEntry + dirSize);
			continue;
		}

		// compare the attribute of this entry with the given attribute
		// go to next entry if the attributes unmatch
		if ((curEntry->attribute & ffInfo->attrib) != curEntry->attribute)
		{
			curEntry = (struct directory *)((unsigned long)curEntry + dirSize);
			continue;
		}
		
		/* marked by chilong 03/07/2002
		// DIR are shown only if DA_DIR is specified by user
		if ((ffInfo->attrib & DA_DIR) == DA_DIR)
			if ((curEntry->attribute & DA_DIR) != DA_DIR)
			{
				curEntry = (struct directory *)((unsigned long)curEntry + dirSize);
				continue;
			}
		   marked by chilong 03/07/2002 */
		   
		/**** modified by MSC 03/07/2002 ****/
		if ((ffInfo->attrib & FF_DA_DIR_OR) == 0)
		{
			// DIR are shown only if DA_DIR is specified by user
			if ((ffInfo->attrib & DA_DIR) == DA_DIR)
				if ((curEntry->attribute & DA_DIR) != DA_DIR)
				{
					curEntry = (struct directory *)((unsigned long)curEntry + dirSize);
					continue;
				}
		}
		/**** modified by MSC 03/07/2002 ****/
				   
		// attributes match, compare filename with the wildcard name
		if (RD_nameCompare(ffInfo->wildname, curEntry->name) == 1)
		{
			// update the ffInternal structure
			ffInfo->nThEntry = i / dirSize;
			ffInfo->block = curBlock;
			// update the ffblk structure
			// copy field from dir entry to result
			ffres->ff_attrib = curEntry->attribute;
			ffres->ff_ftime = curEntry->time;
			ffres->ff_fdate = curEntry->date;
			ffres->ff_fsize = curEntry->fsize;
			// copy the name from dir entry to result
			i = 0;
			
			// modified by chilong 01/29/2002
			//while (curEntry->name[i] != '\0')
			while(curEntry->name[i] != '\0' && i < RD_FNAME_LEN)
			{
				ffres->ff_name[i] = curEntry->name[i];
				i++;
			}
			ffres->ff_name[i] = '\0';

			return 0;
		} // if loop status
		// not found, try next entry
		curEntry = (struct directory *)((unsigned long)curEntry + dirSize);
	} // for loop i

	// not found in this cluster, try next cluster in the chain
	curBlock = (struct diskBlock *)curBlock->nextBlock;
	nThEntry = -1;
  }

  // all clusters in the chain have been searched, file not found
  RDerrno = ERROR_FILE_NOT_EXIST;
  return -1;
}

/*************************************************************
Function : RD_findclose
Description:
	clean up the memory occupied by the previous search
Input:
	ffres - a structure that holds the results of the previous search
Output:
	0	SUCCESS
	-1	FAILURE
**************************************************************/
int RD_findclose(struct ffblk *ffres)
{
  struct ffInternal *ffInfo;	/* internal information for findnext */

  if (InitRD == FALSE)
  {
	RDerrno = ERROR_FILE_SYSTEM_NOT_INIT;
	return -1;
  }

  if (ffres->ff_reserved == 0)
  {
	RDerrno = ERROR_FILE_NOT_EXIST;
	return -1;
  }

  if (ffres->ff_drive != RAMDISK_ID)
  {
	RDerrno = ERROR_INVALID_DEVICE;
	return -1;
  }

  sc_waitSemaphore(RD_SemaphoreID);

  ffInfo = (struct ffInternal *)ffres->ff_reserved;

  ap_free(ffInfo);

  ffres->ff_reserved = 0;

  sc_signalSemaphore(RD_SemaphoreID);

  return 0;
}



/*************************************************************
Function : RD_nameCompare
Description:
	compare a filename with the wildcard name
Input:
	wild - a wildcard name
	name - filename
Output:
	1	the filename matchs
	0	the filename not matchs
**************************************************************/
int RD_nameCompare(unsigned char *wild, unsigned char *name)
{
  int index;

  // added by chilong 01/30/2002
  short cmpIndex = 0;
    
  // still have to deal with single-byte and double-byte mix
  while (*wild != '\0')
  {
	// recursively compare the next part if the current char is a '*'
	// for example,  wild = "*a.txt", name = "aba.txt"
	//		RD_nameCompare("a.txt", "aba.txt")
	// unmatch =>	RD_nameCompare("a.txt", "ba.txt")
	// unmatch =>	RD_nameCompare("a.txt", "a.txt")
	// match!
	if (*wild == '*')
	{
		// skip all successive '*'
		while (*wild == '*')
			wild++;
		if (*wild == '\0')
			return 1;
		index = 0;
		while (*(name + index) != '\0')
		{
			if (RD_nameCompare(wild, (name + index)) == 1)
				return 1;
			if (*(name + index) > 0x80)
				index += 2;	// a double byte char
			else
				index++;	// a single byte char
		}
		return 0;
	}
	// skip one char in name if the current wild name is '?'
	else if (*wild == '?')
	{
		if (*name == '\0')
			return 0;
		else
		{
			wild++;
			if (*name > 0x80)
				name += 2;	// a double byte char
			else
				name++;		// a single byte char
		}
	}
	else if (*wild == '.' && *(wild + 1) == '*' && *(wild + 2) == '\0')
		return 1;
	else
	{
		if (*name > 0x80)
		{
			// the current name char is a double-byte char
			if (*wild != *name || *(wild + 1) != *(name + 1))
				return 0;
			else
			{
				wild += 2;
				name += 2;
			}
		}
		else
		{
			// the current char is a single-byte char
			if (iCompareChar(*wild, *name) != 1)
				return 0;
			else
			{
				wild++;
				name++;
			}
			
			// added by chilong 01/30/2002
			cmpIndex++;
		}
	}
  }

  /* marked by chilong 01/30/2002
  if (*wild == '\0' && *name == '\0')
	return 1;
  else
  	return 0;
     marked by chilong 01/30/2002 */

  /**** modified by chilong 01/30/2002 ****/     
  if (*wild == '\0' && (*name == '\0' || cmpIndex == RD_FNAME_LEN) )
	return 1;
  else
  	return 0;
  /**** modified by chilong 01/30/2002 ****/     
}



#endif	// #ifdef RAMDISK_ID