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campo-sirio/al/cpp_all/filestor.cpp

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Archive Library versione 2.00 git-svn-id: svn://10.65.10.50/trunk@5350 c028cbd2-c16b-5b4b-a496-9718f37d4682
1997-10-09 16:09:54 +00:00
//
// FILESTOR.CPP
//
// Source file for ArchiveLib 2.0
//
// Copyright (c) Greenleaf Software, Inc. 1994-1996
// All Rights Reserved
//
// CONTENTS
//
// ALFile::operator new()
// ALFile::ALFile()
// newALFile()
// ALFile::~ALFile()
// ALFile::LoadBuffer()
// ALFile::FlushBuffer()
// ALFile::Seek()
// ALFile::Open()
// ALFile::MakeTempName()
// ALFile::Create()
// ALFile::Close()
// ALFile::RenameToBackup()
// ALFile::Rename()
// ALFile::UnRename()
// ALFile::Delete()
// ALFile::Clone()
// ALFile::MakeDirectory()
//
// DESCRIPTION
//
// This file contains the C++ member functions to support class
// ALFile. This class works very closely with the parent class,
// ALStorage, found in STORAGE.CPP. You will find in many cases
// the virtual functions found here in the derived class call
// the same function in the parent class to help out with some
// of the work.
// We don't really do anything exciting in the WEP, it is just
//
// REVISION HISTORY
//
// May 22, 1994 1.0A : First release
//
// July 7, 1994 1.0B : Had to make a lot of changes to support file
// management under UNIX.
//
#include "arclib.h"
#if !defined( AL_IBM )
#pragma hdrstop
#endif
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <time.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#if defined( AL_OS2 )
#define INCL_DOSFILEMGR
#include <os2.h>
#include <io.h>
#if defined( AL_BORLAND )
#include <dir.h>
#else
#include <direct.h>
#endif
#else
#include <io.h>
#include <dos.h>
#include <direct.h>
#endif
#include "filestor.h"
//
// NAME
//
// ALFile::operator new()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Memory allocator used when ArchiveLib resides in a 16 bit DLL.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// void * ALArchive::operator new( size_t size )
//
// C SYNOPSIS
//
// None.
//
// VB SYNOPSIS
//
// None.
//
// DELPHI SYNOPSIS
//
// None.
//
// ARGUMENTS
//
// size : The number of bytes that the compiler has decided will be
// necessary to construct a new ALFile object.
//
// DESCRIPTION
//
// When using a DLL, it is easy to get into a dangerous situation when
// creating objects whose ctor and dtor are both in the DLL. The problem
// arises because when you create an object using new, the memory for
// the object will be allocated from the EXE. However, when you destroy
// the object using delete, the memory is freed inside the DLL. Since
// the DLL doesn't really own that memory, bad things can happen.
//
// But, you say, won't the space just go back to the Windows heap regardless
// of who tries to free it? Maybe, but maybe not. If the DLL is using
// a subsegment allocation scheme, it might do some sort of local free
// before returning the space to the windows heap. That is the point where
// you could conceivably cook your heap.
//
// By providing our own version of operator new inside this class, we
// ensure that all memory allocation for the class will be done from
// inside the DLL, not the EXE calling the DLL.
//
// RETURNS
//
// A pointer to some memory that should have been pulled out of the
// heap for the DLL.
//
// EXAMPLE
//
// SEE ALSO
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New release
//
#if defined( AL_BUILDING_DLL )
void AL_DLL_FAR * AL_PROTO
ALFile::operator new( size_t size ) /* Tag internal function */
{
return ::new char[ size ];
}
#endif
//
// NAME
//
// ALFile::ALFile()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++ C VB Delphi
//
// SHORT DESCRIPTION
//
// The ALFile constructor.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// ALFile::ALFile( const char *file_name = "",
// int buffer_size = 4096,
// ALCase name_case = AL_LOWER );
//
// C SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// hALStorage newALFile( char *file_name );
//
// VB SYNOPSIS
//
// Declare Function newALFile Lib "AL20LW" (ByVal file_name$) As Long
//
// DELPHI SYNOPSIS
//
// function newALFile( file_name : PChar ) : hALStorage;
//
// ARGUMENTS
//
// file_name : The initial file name of the ALFile object you are
// creating. The C++ version has a default argument,
// which is a blank string, which will get converted to a
// temporary name before opening the actual disk file.
//
// buffer_size : The size of the object's I/O buffer. The default of 4096
// should give very good performance. Note that C/VB/Delphi
// users don't get any choice about the buffer size! This
// was done strictly in order to cut back on confusion.
//
// name_case : This parameter determines whether the file names will
// always be converted to upper case, lower case, or left
// in mixed case. Under MS-DOS, you shouldn't use mixed
// case, because the O/S file naming convention is case
// insensitive. ArchiveLib will think "TEMP.BAK" and
// "temp.bak" are different, when they really aren't.
//
// Once again, C/VB/Delphi users are stuck with the default.
//
//
// DESCRIPTION
//
// This constructor is used to create a new ALFile object, which will
// usually be treated as an ALStorage object by ArchiveLib functions.
// It is important to note that not much happens during construction of
// this object, the real activity happens after you call the Open()
// function. Just creating this object *does not* create a file on disk!
//
// RETURNS
//
// Nothing, this is a constructor. The C/VB/Delphi translation routines
// return a handle pointing to the newly created ALFile object.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::ALStorage()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New release
//
AL_PROTO
ALFile::ALFile( const char AL_DLL_FAR *file_name /* = "" */, /* Tag public function */
int buffer_size /* = 4096 */,
ALCase name_case /* = AL_LOWER */)
// Note: if non-msdos, change case parameter to AL_MIXED
: ALStorage( file_name, buffer_size, AL_FILE_OBJECT, name_case ) {
miHandle = -1;
}
#if !defined( AL_NO_C )
extern "C" AL_LINKAGE hALStorage AL_FUNCTION
newALFile( char AL_DLL_FAR *file_name ) /* Tag public function */
{
return (hALStorage) new ALFile( file_name );
}
#endif
//
// NAME
//
// ALFile::~ALFile()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// The ALFile destructor.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// ALFile::~ALFile()
//
// C SYNOPSIS
//
// None, use deleteALStorage();
//
// VB SYNOPSIS
//
// None, use deleteALStorage();
//
// DELPHI SYNOPSIS
//
// None, use deleteALStorage();
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// The destructor for an ALFile object doesn't have to do much work.
// The base class destructor will take care of freeing the I/O buffer,
// and any other loose ends. All we have to do here is make sure
// the file gets closed, and that its buffers get flushed to the disk
// file.
//
// Note that in debug mode, the destructor also checks this for the
// correct class type. This helps flag erroneous or duplicated
// destructor calls.
//
// C/VB/Delphi users don't have a specific function to call this guy.
// Instead, the call deleteALStorage(), which will in turn call the
// virtual destructor. If it's an ALFile object, it will get here
// one way or another.
//
// RETURNS
//
// Nothing, it's a dtor!
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::~ALStorage(), ALFile::ALFile()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New release
//
AL_PROTO
ALFile::~ALFile() /* Tag public function */
{
AL_ASSERT( GoodTag(), "~ALFile: attempting to delete invalid object" );
if ( miHandle != -1 )
Close();
}
//
// NAME
//
// ALFile::LoadBuffer()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Load a new batch of data from the file into the local buffer.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::LoadBuffer( long address )
//
// C SYNOPSIS
//
// None, use ALStorageLoadBuffer().
//
// VB SYNOPSIS
//
// None, use ALStorageLoadBuffer().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageLoadBuffer().
//
// ARGUMENTS
//
// address : The long offset into the physical file. A seek/read
// combination will be executed at this location,
// so that subsequent calls to read data will start at
// the given address.
//
// DESCRIPTION
//
// This function is used in the library whenever a byte needs to be read
// that isn't present in the current I/O buffer. It has to use
// the C RTL function lseek() to go to the correct position in the library.
// If that works, it uses the C RTL function read() to read in an I/O
// buffer full of data.
//
// After that operation is performed, muReadIndex is set to 0, indicating
// that the next read from the I/O buffer will take place at location 0.
// mlFilePointer is set to 'address' plus the number of bytes read, so
// we know where the next read from the file will take place. And
// muBufferValidData is set to the count of bytes read in from this
// location. That lets us know how far we can read in the I/O buffer
// before we run out of space.
//
// Note that if CRC checking has been turned on, we will update the
// current working CRC value with the new data that has been read
// in from the buffer.
//
// RETURNS
//
// AL_SUCCESS, AL_SEEK_ERROR, AL_END_OF_FILE, or possibly another
// error code < AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::LoadBuffer(), ALFile::FlushBuffer(), ALStorage::ReadChar()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::LoadBuffer( long address ) /* Tag public function */
{
if ( mStatus < AL_SUCCESS )
return mStatus;
if ( mlFilePointer != address ) {
long result = lseek( miHandle, address, SEEK_SET );
if ( result == -1L )
return mStatus.SetError( AL_SEEK_ERROR,
"Seek failure on %s. errno = %d",
mName.GetName(),
errno );
}
int result = read( miHandle, mpcBuffer, muBufferSize );
if ( result == 0 )
return AL_END_OF_FILE;
if ( result < 0 )
return mStatus.SetError( AL_READ_ERROR,
"Read failure on %s. errno = %d",
mName.GetName(),
errno );
if ( miUpdateCrcFlag )
UpdateCrc( result );
muReadIndex = 0; //Reading can resume at this location in the I/O buffer
mlFilePointer += result;
muBufferValidData = result;
YieldTime();
return result;
}
//
// NAME
//
// ALFile::FlushBuffer()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Flush the internal read/write buffer.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::FlushBuffer()
//
// C SYNOPSIS
//
// None, use ALStorageFlushBuffer().
//
// VB SYNOPSIS
//
// None, use ALStorageFlushBuffer().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageFlushBuffer();
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// This function is the counterpart to LoadBuffer(). It gets called
// when a write operation is poised to overflow the I/O buffer. This
// means we need to flush the buffer out to disk, then reset some
// data members.
//
// Unlike LoadBuffer(), this function doesn't have an address argument,
// so we don't have to perform a seek(). Instead, the data will be
// written out to the current position of the file pointer. If the
// write is successful, muWriteIndex is set to 0, indicating that the
// next write to the I/O buffer can go to position 0. mlFilePointer is
// incremented by the length of the write, so we know where the next read
// or write will occur. Finally, muBufferValidData is set to 0, indicating
// that there is no data in the I/O buffer that has been written, and
// there is no data that can be read.
//
// C/VB/Delphi programmers don't have a direct translation function for
// this call. Instead, the call ALStorageLoadBuffer(), which in turn
// will use the virtual function calling mechanism to come here. At least
// if 'this' is an ALFile object, that is.
//
// RETURNS
//
// An integer status value, AL_SUCCESS, AL_WRITE_ERROR, or possibly some
// status code < AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::FlushBuffer(), ALFile::LoadBuffer()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::FlushBuffer() /* Tag public function */
{
if ( mStatus < 0 )
return mStatus;
if ( muWriteIndex != 0 ) {
if ( miUpdateCrcFlag )
UpdateCrc( muWriteIndex );
int result = write( miHandle, mpcBuffer, muWriteIndex );
if ( (unsigned int) result != muWriteIndex )
return mStatus.SetError( AL_WRITE_ERROR,
"Write failure on %s. "
"result = %d, errno = %d",
mName.GetName(),
result,
errno );
muWriteIndex = 0;
mlFilePointer += result;
}
muReadIndex = 0;
muBufferValidData = 0;
YieldTime();
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::Seek()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Seek to a given position in an input file.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::Seek( long address )
//
// C SYNOPSIS
//
// None, use ALStorageSeek().
//
// VB SYNOPSIS
//
// None, use ALStorageSeek().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageSeek().
//
// ARGUMENTS
//
// address : The address in the physical file to seek to.
//
// DESCRIPTION
//
// This is a function the user can call to position the read/write pointer
// to a new location in the disk file. If there is any data that has been
// written to the I/O buffer, it gets flushed first. After that, we do
// a seek, and update mlFilePointer to reflect the new reality. Note that
// the other important data members will have been updated by FlushBuffer().
//
// And no, this guy doesn't do a LoadBuffer(). Which is fine if you are
// going to do a bunch of writes afterwards. If you are going to read data
// immediately after Seek(), you would have been better of calling
// LoadBuffer().
//
// C/VB/Delphi programmers don't have a direct translation function for
// this call. Instead, they should call ALStorageSeek(), which in turn
// will use the virtual function calling mechanism to come here. At least
// if 'this' is an ALFile object, that is.
//
// RETURNS
//
// AL_SUCCESS, AL_SEEK_ERROR, or possibly some other status code < AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::Seek(), ALFile::Tell()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::Seek( long address ) /* Tag public function */
{
FlushBuffer();
if ( mStatus < 0 )
return mStatus;
if ( mlFilePointer != address ) {
long result = lseek( miHandle, address, SEEK_SET );
if ( result == -1L )
return mStatus.SetError( AL_SEEK_ERROR,
"Seek failure on %s. errno = %d",
mName.GetName(),
errno );
}
mlFilePointer = address;
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::Open()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Open an ALFile object.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::Open()
//
// C SYNOPSIS
//
// None, use ALStorageOpen().
//
// VB SYNOPSIS
//
// None, use ALStorageOpen().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageOpen().
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// This is an important function, because it converts the ALFile
// object from a dinky little unimportant object, to a big massive
// thing that is ready to do serious work.
//
// The first thing we do here is see if we can open the file. We try
// to open it with READ/WRITE privileges, but we give up and drop back
// to READ only if that doesn't work out.
//
// We then call the base class ALStorage::Open() who takes care of
// allocating buffers and initializing data members.
//
// Finally, we have to get the protection attributes and time date
// stamps for the file. After those are stored off, the file is ready
// for abuse.
//
// C/VB/Delphi programmers don't have a direct translation function for
// this call. Instead, they should call ALStorageOpen(), which in turn
// will use the virtual function calling mechanism to come here. At least
// if 'this' is an ALFile object, that is.
//
// RETURNS
//
// AL_CANT_OPEN_FILE, AL_SUCCESS, or possibly some other error code
// < AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALFile::Create(), ALStorage::Open()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::Open() /* Tag public function */
{
if ( mStatus < AL_SUCCESS )
return mStatus;
miHandle = open( mName, O_BINARY | O_RDWR );
if ( miHandle == -1 && errno == EACCES )
miHandle = open( mName, O_BINARY | O_RDONLY );
if ( miHandle == -1 )
return mStatus.SetError( AL_CANT_OPEN_FILE,
"File open failure. Open of %s returned "
"errno = %d",
mName.GetName(),
errno );
ALStorage::Open();
struct stat buf;
struct tm AL_DLL_FAR *tblock;
if ( stat( mName, &buf ) == -1 )
return mStatus.SetError( AL_CANT_OPEN_FILE,
"Couldn't get time, date, and size "
"information for %s. errno = %d.",
mName.GetName(),
errno );
mlSize = buf.st_size;
tblock = localtime( &buf.st_mtime );
mTimeDate.SetTimeDate( tblock );
#if defined( AL_WINDOWS ) && defined( AL_FLAT_MODEL )
TIME_ZONE_INFORMATION tzi;
GetTimeZoneInformation( &tzi );
long result = mTimeDate.GetUnixTime();
result -= tzi.Bias * 60;
mTimeDate.SetTimeDate( result );
#endif
ReadAttributesFromFileSys();
if ( mStatus < 0 )
return mStatus;
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::MakeTempName( int i )
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Private function to make a temporary filename.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// void ALFile::MakeTempName( int i )
//
// C SYNOPSIS
//
// None, this is an internal C++ member function.
//
// VB SYNOPSIS
//
// None, this is an internal C++ member function.
//
// DELPHI SYNOPSIS
//
// None, this is an internal C++ member function.
//
// ARGUMENTS
//
// i : A numeric argument that can somehow be incorporated into
// the temporary file name. Create() will call this function
// while incrementing this number in an attempt to find a unique
// name.
//
// DESCRIPTION
//
// This function is called by Create() and other functions when they
// decide they need to cook up a temporary file name. The single parameter
// i is incremented by the calling program so that repeated calls should
// eventually produce a unique name.
//
// All this function does to create that unique name is perform a sprintf()
// into a buffer using a simple template. The result is copied into the
// mName member, and is ready to be tried out.
//
//
// RETURNS
//
// Nothing.
//
// EXAMPLE
//
// SEE ALSO
//
// ALFile::Create()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
void AL_PROTO
ALFile::MakeTempName( int i ) /* Tag protected function */
{
char name[ 21 ];
sprintf( name, "~al~%03d.tmp", i );
mName = name;
}
//
// NAME
//
// ALFile::Create()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Create a new physical file using an ALFile object.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::Create( long )
//
// C SYNOPSIS
//
// None, use ALStorageCreate().
//
// VB SYNOPSIS
//
// None, use ALStorageCreate().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageCreate().
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// This function is used to create a new file storage object. Since
// we are creating a new object, we must be able to open it with read
// access. We will also rudely obliterate any existing file.
//
// The first thing we do here is call the base class Create() function.
// It takes care of setting up the I/O buffer and initializing the
// data members used to support the class.
//
// Since this is a virtual function in a derived class, C/VB/Delphi
// programmers aren't going to be able to call it directly. They
// will instead call ALStorageCreate(), which will wind up here
// via the virtual function mechanism.
//
// RETURNS
//
// AL_SUCCESS, AL_CANT_OPEN_FILE, or possibly some other error code
// < AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::Create(), ALFile::Open()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::Create( long ) /* Tag public function */
{
ALStorage::Create();
if ( mStatus < AL_SUCCESS )
return mStatus;
char AL_DLL_FAR *p = mName;
int i;
//
// We don't try to make a directory for unnamed temp files.
//
if ( p == 0 || p[ 0 ] == 0 ) {
for ( i = 0 ; i < 999 ; i++ ) {
MakeTempName( i );
miHandle = open( mName,
O_CREAT | O_RDWR | O_BINARY | O_EXCL,
S_IREAD | S_IWRITE );
if ( miHandle != -1 )
break;
else if ( errno != EEXIST && errno != EACCES ) {
mStatus.SetError( AL_CANT_OPEN_FILE,
"Temporary file creation failure. "
"Open of %s returned errno = %d",
mName.GetName(),
errno );
mName = "";
return AL_CANT_OPEN_FILE;
}
}
if ( i == 1000 ) {
mStatus.SetError( AL_CANT_OPEN_FILE,
"Temporary file creation failure. "
"Tried 1000 times to open %s "
"(or a name something like that).",
mName.GetName() );
mName = "";
return AL_CANT_OPEN_FILE;
}
} else {
miHandle = open( mName,
O_CREAT | O_RDWR | O_BINARY | O_TRUNC,
S_IREAD | S_IWRITE );
//
// Handle failure to make directories here
//
if ( miHandle == -1 &&
errno == ENOENT &&
( strchr( mName, '/' ) || strchr( mName, '\\' ) ) ) {
if ( MakeDirectory() ) {
miHandle = open( mName,
O_CREAT | O_RDWR | O_BINARY | O_TRUNC,
S_IREAD | S_IWRITE );
}
}
}
if ( miHandle == -1 && mAttributes.Directory() == 0 )
return mStatus.SetError( AL_CANT_OPEN_FILE,
"File creation failure. "
"Open of %s returned errno = %d",
mName.GetName(),
errno );
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::Close()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Close the physical file associated with an ALFile object.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::Close()
//
// C SYNOPSIS
//
// None, use ALStorageClose().
//
// VB SYNOPSIS
//
// None, use ALStorageClose().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageClose().
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// This function is called when you are done accessing a file, and want
// to free up its resources. The first thing it does is check to see
// if the file was ever actually opened. If it was, we flush the output
// buffer, then calculate and store the file length. Finally, we close
// the disk file, then call the base class Close() function to clean up
// the buffers and deal with other miscellaneous dirty work.
//
// Since this is a virtual function in a derived class, C/VB/Delphi
// programmers aren't going to be able to call it directly. They
// will instead call ALStorageClose(), which will wind up here
// via the virtual function mechanism.
//
// RETURNS
//
// Any status code, hopefully AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::Close(), ALFile::Create(), ALFile::Open()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
//
// Note: eventually I need to move the O/S specific code here into
// cpp_fs.nt, cpp_fs.os2, and cpp_fs.dos.
//
int AL_PROTO
ALFile::Close() /* Tag public function */
{
if ( miHandle == -1 )
return mStatus;
FlushBuffer();
mlSize = filelength( miHandle );
if ( miCreated && mTimeDate.Valid() ) {
#if defined( AL_WIN32 )
TIME_ZONE_INFORMATION tzi;
GetTimeZoneInformation( &tzi );
long result = mTimeDate.GetUnixTime();
result += tzi.Bias * 60;
mTimeDate.SetTimeDate( result );
FILETIME FileTime;
LPFILETIME lpFileTime = &FileTime;
WORD wDosDate = (WORD) mTimeDate.GetDosDate();
WORD wDosTime = (WORD) mTimeDate.GetDosTime();
DosDateTimeToFileTime( wDosDate, wDosTime, lpFileTime );
# if defined( AL_WATCOM )
SetFileTime( (HANDLE) _os_handle( miHandle ), NULL, NULL, lpFileTime );
# else
SetFileTime( (HANDLE) _get_osfhandle( miHandle ), NULL, NULL, lpFileTime );
# endif
#elif defined( AL_OS2 )
// going to do it all after the file is closed
#else
_dos_setftime( miHandle,
mTimeDate.GetDosDate(),
mTimeDate.GetDosTime() );
#endif
}
close( miHandle );
miHandle = -1;
ALStorage::Close();
if ( miCreated && mTimeDate.Valid() )
WriteAttributesToFileSys();
return mStatus;
}
//
// NAME
//
// ALFile::RenameToBackup()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Rename the physical file on disk to a suitable backup name.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::RenameToBackup( int delete_on_clash = 1 );
//
// C SYNOPSIS
//
// None, use ALStorageRenameToBackup().
//
// VB SYNOPSIS
//
// None, use ALStorageRenameToBackup().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageRenameToBackup().
//
// ARGUMENTS
//
// delete_on_clash : If this flag is set, it means that we will overwrite
// an existing file with this file if the names clash.
// For example, if I am renaming TEMP.DAT to TEMP.BAK,
// and a TEMP.BAK already exists, I will delete it
// before renaming if this arg is set.
//
// DESCRIPTION
//
// This function is a quick way to rename a storage object. The new
// name created is the default name, which usually means changing the
// file extension to ".BAK", from whatever it was.
//
// You don't see it here, but both the mName member and the physical file
// name are updated. That all happens in the Rename() function.
//
// Since this is a virtual function in a derived class, C/VB/Delphi
// programmers aren't going to be able to call it directly. They
// will instead call ALStorageRenameToBackup(), which will wind up here
// via the virtual function mechanism.
//
// RETURNS
//
// AL_SUCCESS or AL_RENAME_ERROR.
//
// EXAMPLE
//
// SEE ALSO
//
// ALFile::Rename(), ALStorage::RenameToBackup()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::RenameToBackup( int delete_on_clash /* = 1 */ ) /* Tag public function */
{
mName.ChangeExtension();
return Rename( 0, delete_on_clash );
}
//
// NAME
//
// ALFile::Rename()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Rename an existing file on disk.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::Rename( const char *new_name = 0,
// int delete_on_clash = 1 );
//
// C SYNOPSIS
//
// None, use ALStorageRename().
//
// VB SYNOPSIS
//
// None, use ALStorageRename().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageRename().
//
// ARGUMENTS
//
// new_name : A character pointer to a new file name. If a name is
// defined here, the file is renamed to this new value.
// If this value is 0, it means that we expect that
// the mName member has already been updated with a
// new name. In this case, the old name of the
// file is renamed to the new name.
//
// delete_on_clash : If this flag is set, it means that we will overwrite
// an existing file with this file if the names clash.
// For example, if I am renaming TEMP.DAT to TEMP.BAK,
// and a TEMP.BAK already exists, I will delete it
// before renaming if this arg is set.
//
//
// DESCRIPTION
//
// This virtual function provides a way to rename a storage object's
// physical implementation. It first updates the mName member if a
// new_name argument is provided. After that, we unlink the clash file
// if one exists, then do a simple rename of mName.mszOldName to
// new_name.
//
// Note that this function does a lot of error checking in debug mode.
// It also does a little error checking in release mode.
//
// Since this is a virtual function in a derived class, C/VB/Delphi
// programmers aren't going to be able to call it directly. They
// will instead call ALStorageRename(), which will wind up here
// via the virtual function mechanism.
//
// RETURNS
//
// AL_SUCCESS or AL_RENAME_ERROR.
//
// EXAMPLE
//
// SEE ALSO
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::Rename( const char AL_DLL_FAR *new_name /* = 0 */, /* Tag public function */
int delete_on_clash /* = 1 */ )
{
AL_ASSERT( miHandle == -1, "Rename: attempting to rename open file" );
AL_ASSERT( mName.GetName() != 0, "Rename: attempting to rename file with null name" );
AL_ASSERT( strlen( mName ) > 0, "Rename: attempting to rename file with 0 length name" );
int status;
const char AL_DLL_FAR *real_old_name;
const char AL_DLL_FAR *real_new_name;
if ( new_name ) {
real_old_name = mName.GetSafeName();
real_new_name = new_name;
} else {
real_old_name = mName.GetSafeOldName();
real_new_name = mName.GetSafeName();
}
#if !defined( AL_WIN32 )
const char AL_DLL_FAR *p = strrchr( real_new_name, '.' );
if ( p && strlen( p ) > 4 )
return mStatus.SetError( AL_RENAME_ERROR,
"Error trying to rename %s. It has a long "
"extension, which could lead to inadvertent "
"deletion of a file when trying to rename.",
real_old_name );
#endif
if ( delete_on_clash ) {
if ( mName.mCase == AL_MIXED )
status = strcmp( real_new_name, real_old_name );
else
status = stricmp( real_new_name, real_old_name );
if ( status == 0 )
return mStatus.SetError( AL_RENAME_ERROR,
"Error attempting to rename %s to %s. "
"Can't rename to the same name!",
real_new_name,
real_old_name );
status = unlink( real_new_name );
if ( status != 0 && errno != ENOENT )
return mStatus.SetError( AL_RENAME_ERROR,
"Error deleting %s before renaming %s. "
"errno = %d",
real_new_name,
real_old_name,
errno );
}
status = rename( real_old_name, real_new_name );
if ( status != 0 )
return mStatus.SetError( AL_RENAME_ERROR,
"Error renaming %s to %s. errno = %d",
real_old_name,
real_new_name,
errno );
if ( new_name != 0 )
mName = new_name;
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::UnRename()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Undo the renaming of a file.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::UnRename( int delete_on_clash = 1 );
///
// C SYNOPSIS
//
// None, use ALStorageUnRename().
//
// VB SYNOPSIS
//
// None, use ALStorageUnRename().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageUnRename().
//
// ARGUMENTS
//
// delete_on_clash : If this flag is set, it means that we will overwrite
// an existing file with this file if the names clash.
// For example, if I am renaming TEMP.BAK to TEMP.DAT,
// and a TEMP.DAT already exists, I will delete it
// before renaming if this arg is set.
//
// DESCRIPTION
//
// This virtual function provides a way to undo a previous renaming of
// a storage object's physical name. We can do this because the mName
// member of ALStorage keeps track both of the current name of the file,
// and the old name. In this case, we just rename the current name to
// the old name. Then we update the mName member so it is accurate.
//
// Note that this function does a lot of error checking in debug mode.
// It also does a little error checking in release mode.
//
// Since this is a virtual function in a derived class, C/VB/Delphi
// programmers aren't going to be able to call it directly. They
// will instead call ALStorageRename(), which will wind up here
// via the virtual function mechanism.
//
// RETURNS
//
// AL_SUCCESS or AL_RENAME_ERROR.
//
// EXAMPLE
//
// SEE ALSO
//
// ALStorage::UnRename(), ALFile::Rename()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::UnRename( int delete_on_clash /* = 1 */ ) /* Tag public function */
{
AL_ASSERT( miHandle == -1, "UnRename: attempting to rename open file" );
AL_ASSERT( mName.GetName() != 0, "UnRename: attempting to rename file with null name" );
AL_ASSERT( mName.GetOldName() != 0, "UnRename: attempting to rename file with null old name" );
AL_ASSERT( strlen( mName ) > 0, "UnRename: attempting to rename file with 0 length name" );
AL_ASSERT( strlen( mName.GetOldName() ) > 0, "UnRename: attempting to rename file with 0 length old name" );
int status;
if ( delete_on_clash ) {
status = unlink( mName.GetOldName() );
if ( status != 0 && errno != ENOENT )
return mStatus.SetError( AL_RENAME_ERROR,
"Error deleting %s before renaming %s. "
"errno = %d",
mName.GetOldName(),
mName.GetName(),
errno );
}
status = rename( mName, mName.GetOldName() );
if ( status != 0 && errno != ENOENT )
return mStatus.SetError( AL_RENAME_ERROR,
"Error renaming %s to %s. errno = %d",
mName.GetName(),
mName.GetOldName(),
errno );
ALStorage::mName = mName.GetOldName();
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::Delete()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Delete the underlying physical file associated with an ALFile object.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::Delete()
//
// C SYNOPSIS
//
// None, use ALStorageDelete().
//
// VB SYNOPSIS
//
// None, use ALStorageDelete().
//
// DELPHI SYNOPSIS
//
// None, use ALStorageDelete().
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// This function is called to delete the physical object associated with
// a file. This simply means calling the unlink() function for the
// given name.
//
// Since this is a virtual function in a derived class, C/VB/Delphi
// programmers aren't going to be able to call it directly. They
// will instead call ALStorageDelete(), which will wind up here
// via the virtual function mechanism.
//
// RETURNS
//
// AL_DELETE_ERROR or AL_SUCCESS.
//
// EXAMPLE
//
// SEE ALSO
//
// ALFile::ALFile(), ALStorage::Delete()
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO
ALFile::Delete() /* Tag public function */
{
AL_ASSERT( miHandle == -1, "Delete: attempting to delete open file" );
AL_ASSERT( mName.GetName() != 0, "Delete: attempting to delete file with null name" );
AL_ASSERT( strlen( mName ) > 0, "Delete: attempting to delete file with 0 length name" );
int status = unlink( mName );
if ( status != 0 )
return mStatus.SetError( AL_DELETE_ERROR,
"Error deleting file %s, errno = %d ",
mName.GetName(),
errno );
return AL_SUCCESS;
}
//
// NAME
//
// ALFile::Clone()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Clone this file object.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// ALStorage * ALFile::Clone( const char *name,
// int object_type ) const;
//
// C SYNOPSIS
//
// None, this is an internal C++ function
//
// VB SYNOPSIS
//
// None.
//
// DELPHI SYNOPSIS
//
// None.
//
// ARGUMENTS
//
// name : The desired name of the new object. Usually this will
// be a name found in an Archive directory.
//
// object_type : The type of object we want to create. Only
// AL_STORAGE_DEFAULT and AL_FILE_OBJECT will cause this
// function to succeed.
//
// DESCRIPTION
//
// The virtual Clone() function is used by archiving programs to act
// as a virtual constructor. When preparing to create storage objects
// based on the contents of an Archive directory, the archiving code can
// call Clone() for all the storage objects in its toolkit until it finds
// one that responds to its object type.
//
// For example, if an archive contained an AL_MEMORY object, and we were
// extracting, and an ALFile object was in the toolkit, it would call
// ALFile::Clone() from the toolkit object, with an object type of
// AL_MEMORY_OBJECT. This Clone() function would fail. Hopefully, there
// would be a memory based storage object in the toolkit that would
// respond properly to the Clone() call.
//
// Another object in the same archive might have an AL_FILE_OBJECT type.
// When the archiving code called Clone() again with that object type,
// we would successfully create the new File object in Clone().
//
// RETURNS
//
// Either a pointer to a newly constructed ALFile object, or a zero
// in case of error.
//
// EXAMPLE
//
// SEE ALSO
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
ALStorage AL_DLL_FAR * AL_PROTO
ALFile::Clone( const char AL_DLL_FAR *name, /* Tag public function */
int object_type ) const
{
switch ( object_type ) {
case AL_STORAGE_DEFAULT :
case AL_FILE_OBJECT :
return new ALFile( name );
}
return 0;
}
//
// NAME
//
// ALFile::MakeDirectory()
//
// PLATFORMS/ENVIRONMENTS
//
// Console Windows PM
// C++
//
// SHORT DESCRIPTION
//
// Make a directory or a series of directories.
//
// C++ SYNOPSIS
//
// #include "arclib.h"
// #include "filestor.h"
//
// int ALFile::MakeDirectory()
//
// C SYNOPSIS
//
// None, this is an internal C++ function
//
// VB SYNOPSIS
//
// None.
//
// DELPHI SYNOPSIS
//
// None.
//
// ARGUMENTS
//
// None.
//
// DESCRIPTION
//
// If ALFile::Create() fails due to the target directory
// not existing, it calls this routine. This guy works his
// way through a long file name, trying to make directories
// all the way down, until it finishes or fails.
//
// For example, if the mName member of this contains a string
// like c:\mark\al200\temp\temp.c, this routine will attempt
// to make, in turn:
// c:\ (starts at root)
// c:\mark
// c:\mark\al200
// c:\mark\al200\temp
//
// RETURNS
//
// 1 for success, 0 for failure.
//
// EXAMPLE
//
// SEE ALSO
//
// REVISION HISTORY
//
// February 14, 1996 2.0A : New Release
//
int AL_PROTO ALFile::MakeDirectory() /* Tag protected function */
{
char *p = new char[ strlen( mName ) + 1 ];
if ( p ) {
strcpy( p, mName );
//
// Now I need to work through the entire file name, creating
// each directory in order. I do this by stuffing a 0 into
// successive locations in the string where i find a '/' character,
// and calling mkdir() at each point.
//
for ( size_t i = 0 ; p[ i ] ; i++ ) {
size_t j = i;
i = strcspn( p + i, "/\\" );
if ( i == strlen( p + j ) ) {
delete[] p;
return 1;
}
i += j;
char temp = p[ i ];
p[ i ] = '\0';
if ( mkdir( p ) == -1 && errno != EACCES ) {
delete[] p;
return 0;
}
p[ i ] = temp;
}
delete[] p;
}
return 0;
}
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