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FileHeader Class Reference

#include <filehdr.h>

List of all members.

Public Methods

bool Allocate (BitMap *bitMap, int fileSize)
void Deallocate (BitMap *bitMap)
void FetchFrom (int sectorNumber)
void WriteBack (int sectorNumber)
int ByteToSector (int offset)
int FileLength ()
void Print ()

Private Attributes

int numBytes
int numSectors
int dataSectors [NumDirect]

Member Function Documentation

bool FileHeader::Allocate (  BitMap *    bitMap,
int    fileSize
) 
 

Definition at line 42 of file filehdr.cc.

References dataSectors, divRoundUp, FALSE, BitMap::Find, numBytes, BitMap::NumClear, numSectors, SectorSize, and TRUE.

Referenced by FileSystem::Create, and FileSystem::FileSystem. 

00043 { 
00044     numBytes = fileSize;
00045     numSectors  = divRoundUp(fileSize, SectorSize);
00046     if (freeMap->NumClear() < numSectors)
00047         return FALSE;           // not enough space
00048 
00049     for (int i = 0; i < numSectors; i++)
00050         dataSectors[i] = freeMap->Find();
00051     return TRUE;
00052 }

int FileHeader::ByteToSector (  int    offset ) 
 

Definition at line 107 of file filehdr.cc.

References dataSectors, and SectorSize.

Referenced by OpenFile::ReadAt, and OpenFile::WriteAt. 

00108 {
00109     return(dataSectors[offset / SectorSize]);
00110 }

void FileHeader::Deallocate (  BitMap *    bitMap ) 
 

Definition at line 62 of file filehdr.cc.

References ASSERT, BitMap::Clear, dataSectors, numSectors, and BitMap::Test.

Referenced by FileSystem::Remove. 

00063 {
00064     for (int i = 0; i < numSectors; i++) {
00065         ASSERT(freeMap->Test((int) dataSectors[i]));  // ought to be marked!
00066         freeMap->Clear((int) dataSectors[i]);
00067     }
00068 }

void FileHeader::FetchFrom (  int    sectorNumber ) 
 

Definition at line 78 of file filehdr.cc.

Referenced by OpenFile::OpenFile, FileSystem::Print, Directory::Print, and FileSystem::Remove. 

00079 {
00080     synchDisk->ReadSector(sector, (char *)this);
00081 }

int FileHeader::FileLength (    ) 
 

Definition at line 118 of file filehdr.cc.

References numBytes.

Referenced by OpenFile::Length, OpenFile::ReadAt, and OpenFile::WriteAt. 

00119 {
00120     return numBytes;
00121 }

void FileHeader::Print (    ) 
 

Definition at line 130 of file filehdr.cc.

References dataSectors, j, numBytes, numSectors, and SectorSize.

Referenced by FileSystem::Print, and Directory::Print. 

00131 {
00132     int i, j, k;
00133     char *data = new char[SectorSize];
00134 
00135     printf("FileHeader contents.  File size: %d.  File blocks:\n", numBytes);
00136     for (i = 0; i < numSectors; i++)
00137         printf("%d ", dataSectors[i]);
00138     printf("\nFile contents:\n");
00139     for (i = k = 0; i < numSectors; i++) {
00140         synchDisk->ReadSector(dataSectors[i], data);
00141         for (j = 0; (j < SectorSize) && (k < numBytes); j++, k++) {
00142             if ('\040' <= data[j] && data[j] <= '\176')   // isprint(data[j])
00143                 printf("%c", data[j]);
00144             else
00145                 printf("\\%x", (unsigned char)data[j]);
00146         }
00147         printf("\n"); 
00148     }
00149     delete [] data;
00150 }

void FileHeader::WriteBack (  int    sectorNumber ) 
 

Definition at line 91 of file filehdr.cc.

Referenced by FileSystem::Create, and FileSystem::FileSystem. 

00092 {
00093     synchDisk->WriteSector(sector, (char *)this); 
00094 }

Member Data Documentation

int FileHeader::dataSectors[NumDirect] [private]
 

Definition at line 62 of file filehdr.h.

Referenced by Allocate, ByteToSector, Deallocate, and Print.

int FileHeader::numBytes [private]
 

Definition at line 60 of file filehdr.h.

Referenced by Allocate, FileLength, and Print.

int FileHeader::numSectors [private]
 

Definition at line 61 of file filehdr.h.

Referenced by Allocate, Deallocate, and Print.

The documentation for this class was generated from the following files:
Generated on Mon Feb 10 09:54:55 2003 for nachos by doxygen1.2.14 written by Dimitri van Heesch, © 1997-2002
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