fat16finddirentry.c

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#ifndef _FAT_DEFINE
 #include "FAT.c"
#endif

BYTE FAT16FindDIREntry(CHAR *DirName);

BYTE FAT16FindDIREntry(CHAR *DirName)
{
	xdata BYTE i,j,m;
	xdata CHAR temp[27];
	xdata DWORD Sector;
	xdata struct FATClusterStr ReadCluster;

	if (FAT.CurrentDirectory==FAT.RootClus)						//根目录
	{
		Sector=FAT.CurrentDirectory;
		for(m=0;m<FAT.RootSectors;m++)
		{
			StorageMedia.ReadSector(Sector++,DiskBuffer);
			for (i=0;i<16;i++)
			{
				if (sDIR[i].Attr&FAT_ATTR_VOLUME_ID) continue;		//如果是卷标则跳过
				if (sDIR[i].Name[0]==0xe5||sDIR[i].Name[0]==0x00) continue;			//空目录项跳过
				for(j=0;j<11;j++)
					temp[j]=sDIR[i].Name[j];
				temp[j]=0;
				if (strcmp((const char *)DirName,(const char *)temp)==0) return(i);
			}
		}
	}
	else
	{
		ReadCluster.Cluster=FAT.CurrentDirectory;
		ReadCluster.SecOffset=0;
		while(ReadCluster.Cluster!=FAT_CLUSTER_END16)
		{
			FATReadCluster(&ReadCluster,DiskBuffer);
			for (i=0;i<16;i++)
			{
				if (sDIR[i].Attr&FAT_ATTR_VOLUME_ID) continue;		//如果是卷标则跳过
				if (sDIR[i].Name[0]==0xe5||sDIR[i].Name[0]==0x00) continue;			//空目录项跳过
				for(j=0;j<11;j++)
					temp[j]=sDIR[i].Name[j];
				temp[j]=0;
				if (strcmp((const char *)DirName,(const char *)temp)==0) return(i);
			}
		}
	}
	return(i);
}