usbloadergx/source/libntfs/ntfsfile.c
giantpune 9e79c9d99b * remove little unused code
* code cleanup
2010-09-18 23:16:05 +00:00

582 lines
14 KiB
C

/**
* ntfsfile.c - devoptab file routines for NTFS-based devices.
*
* Copyright (c) 2010 Dimok
* Copyright (c) 2009 Rhys "Shareese" Koedijk
* Copyright (c) 2006 Michael "Chishm" Chisholm
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program/include file is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include "ntfsinternal.h"
#include "ntfsfile.h"
#define STATE(x) ((ntfs_file_state*)x)
void ntfsCloseFile ( ntfs_file_state *file )
{
// Sanity check
if ( !file || !file->vd )
return;
// Special case fix ups for compressed and/or encrypted files
if ( file->compressed )
ntfs_attr_pclose( file->data_na );
#ifdef HAVE_SETXATTR
if ( file->encrypted )
ntfs_efs_fixup_attribute( NULL, file->data_na );
#endif
// Close the file data attribute (if open)
if ( file->data_na )
ntfs_attr_close( file->data_na );
// Sync the file (and its attributes) to disc
if ( file->write )
{
ntfsUpdateTimes( file->vd, file->ni, NTFS_UPDATE_ATIME | NTFS_UPDATE_CTIME );
ntfsSync( file->vd, file->ni );
}
if ( file->read )
ntfsUpdateTimes( file->vd, file->ni, NTFS_UPDATE_ATIME );
// Close the file (if open)
if ( file->ni )
ntfsCloseEntry( file->vd, file->ni );
// Reset the file state
file->ni = NULL;
file->data_na = NULL;
file->flags = 0;
file->read = false;
file->write = false;
file->append = false;
file->pos = 0;
file->len = 0;
return;
}
int ntfs_open_r ( struct _reent *r, void *fileStruct, const char *path, int flags, int mode )
{
ntfs_log_trace( "fileStruct %p, path %s, flags %i, mode %i\n", fileStruct, path, flags, mode );
ntfs_file_state* file = STATE( fileStruct );
// Get the volume descriptor for this path
file->vd = ntfsGetVolume( path );
if ( !file->vd )
{
r->_errno = ENODEV;
return -1;
}
// Lock
ntfsLock( file->vd );
// Determine which mode the file is opened for
file->flags = flags;
if ( ( flags & 0x03 ) == O_RDONLY )
{
file->read = true;
file->write = false;
file->append = false;
}
else if ( ( flags & 0x03 ) == O_WRONLY )
{
file->read = false;
file->write = true;
file->append = ( flags & O_APPEND );
}
else if ( ( flags & 0x03 ) == O_RDWR )
{
file->read = true;
file->write = true;
file->append = ( flags & O_APPEND );
}
else
{
r->_errno = EACCES;
ntfsUnlock( file->vd );
return -1;
}
// Try and find the file and (if found) ensure that it is not a directory
file->ni = ntfsOpenEntry( file->vd, path );
if ( file->ni && ( file->ni->mrec->flags & MFT_RECORD_IS_DIRECTORY ) )
{
ntfsCloseEntry( file->vd, file->ni );
ntfsUnlock( file->vd );
r->_errno = EISDIR;
return -1;
}
// Are we creating this file?
if ( flags & O_CREAT )
{
// The file SHOULD NOT already exist
if ( file->ni )
{
ntfsCloseEntry( file->vd, file->ni );
ntfsUnlock( file->vd );
r->_errno = EEXIST;
return -1;
}
// Create the file
file->ni = ntfsCreate( file->vd, path, S_IFREG, NULL );
if ( !file->ni )
{
ntfsUnlock( file->vd );
return -1;
}
}
// Sanity check, the file should be open by now
if ( !file->ni )
{
ntfsUnlock( file->vd );
r->_errno = ENOENT;
return -1;
}
// Open the files data attribute
file->data_na = ntfs_attr_open( file->ni, AT_DATA, AT_UNNAMED, 0 );
if ( !file->data_na )
{
ntfsCloseEntry( file->vd, file->ni );
ntfsUnlock( file->vd );
return -1;
}
// Determine if this files data is compressed and/or encrypted
file->compressed = NAttrCompressed( file->data_na ) || ( file->ni->flags & FILE_ATTR_COMPRESSED );
file->encrypted = NAttrEncrypted( file->data_na ) || ( file->ni->flags & FILE_ATTR_ENCRYPTED );
// We cannot read/write encrypted files
if ( file->encrypted )
{
ntfs_attr_close( file->data_na );
ntfsCloseEntry( file->vd, file->ni );
ntfsUnlock( file->vd );
r->_errno = EACCES;
return -1;
}
// Make sure we aren't trying to write to a read-only file
if ( ( file->ni->flags & FILE_ATTR_READONLY ) && file->write )
{
ntfs_attr_close( file->data_na );
ntfsCloseEntry( file->vd, file->ni );
ntfsUnlock( file->vd );
r->_errno = EROFS;
return -1;
}
// Truncate the file if requested
if ( ( flags & O_TRUNC ) && file->write )
{
if ( ntfs_attr_truncate( file->data_na, 0 ) )
{
ntfs_attr_close( file->data_na );
ntfsCloseEntry( file->vd, file->ni );
ntfsUnlock( file->vd );
r->_errno = errno;
return -1;
}
}
// Set the files current position and length
file->pos = 0;
file->len = file->data_na->data_size;
ntfs_log_trace( "file->len %d\n", file->len );
// Update file times
ntfsUpdateTimes( file->vd, file->ni, NTFS_UPDATE_ATIME );
// Insert the file into the double-linked FILO list of open files
if ( file->vd->firstOpenFile )
{
file->nextOpenFile = file->vd->firstOpenFile;
file->vd->firstOpenFile->prevOpenFile = file;
}
else
{
file->nextOpenFile = NULL;
}
file->prevOpenFile = NULL;
file->vd->firstOpenFile = file;
file->vd->openFileCount++;
// Unlock
ntfsUnlock( file->vd );
return ( int )fileStruct;
}
int ntfs_close_r ( struct _reent *r, int fd )
{
ntfs_log_trace( "fd %p\n", fd );
ntfs_file_state* file = STATE( fd );
// Sanity check
if ( !file || !file->vd )
{
r->_errno = EBADF;
return -1;
}
// Lock
ntfsLock( file->vd );
// Close the file
ntfsCloseFile( file );
// Remove the file from the double-linked FILO list of open files
file->vd->openFileCount--;
if ( file->nextOpenFile )
file->nextOpenFile->prevOpenFile = file->prevOpenFile;
if ( file->prevOpenFile )
file->prevOpenFile->nextOpenFile = file->nextOpenFile;
else
file->vd->firstOpenFile = file->nextOpenFile;
// Unlock
ntfsUnlock( file->vd );
return 0;
}
ssize_t ntfs_write_r ( struct _reent *r, int fd, const char *ptr, size_t len )
{
ntfs_log_trace( "fd %p, ptr %p, len %Li\n", fd, ptr, len );
ntfs_file_state* file = STATE( fd );
ssize_t written = 0;
off_t old_pos = 0;
// Sanity check
if ( !file || !file->vd || !file->ni || !file->data_na )
{
r->_errno = EINVAL;
return -1;
}
// Short circuit cases where we don't actually have to do anything
if ( !ptr || len <= 0 )
{
return 0;
}
// Lock
ntfsLock( file->vd );
// Check that we are allowed to write to this file
if ( !file->write )
{
ntfsUnlock( file->vd );
r->_errno = EACCES;
return -1;
}
// If we are in append mode, backup the current position and move to the end of the file
if ( file->append )
{
old_pos = file->pos;
file->pos = file->len;
}
// Write to the files data atrribute
while ( len )
{
ssize_t ret = ntfs_attr_pwrite( file->data_na, file->pos, len, ptr );
if ( ret <= 0 )
{
ntfsUnlock( file->vd );
r->_errno = errno;
return -1;
}
len -= ret;
file->pos += ret;
written += ret;
}
// If we are in append mode, restore the current position to were it was prior to this write
if ( file->append )
{
file->pos = old_pos;
}
// Mark the file for archiving (if we actually wrote something)
if ( written )
file->ni->flags |= FILE_ATTR_ARCHIVE;
// Update the files data length
file->len = file->data_na->data_size;
// Unlock
ntfsUnlock( file->vd );
return written;
}
ssize_t ntfs_read_r ( struct _reent *r, int fd, char *ptr, size_t len )
{
ntfs_log_trace( "fd %p, ptr %p, len %Li\n", fd, ptr, len );
ntfs_file_state* file = STATE( fd );
ssize_t read = 0;
// Sanity check
if ( !file || !file->vd || !file->ni || !file->data_na )
{
r->_errno = EINVAL;
return -1;
}
// Short circuit cases where we don't actually have to do anything
if ( !ptr || len <= 0 )
{
return 0;
}
// Lock
ntfsLock( file->vd );
// Check that we are allowed to read from this file
if ( !file->read )
{
ntfsUnlock( file->vd );
r->_errno = EACCES;
return -1;
}
// Don't read past the end of file
if ( file->pos + len > file->len )
{
r->_errno = EOVERFLOW;
len = file->len - file->pos;
ntfs_log_trace( "EOVERFLOW" );
}
ntfs_log_trace( "file->pos:%d, len:%d, file->len:%d \n", ( u32 )file->pos, ( u32 )len, ( u32 )file->len );
// Read from the files data attribute
while ( len )
{
ssize_t ret = ntfs_attr_pread( file->data_na, file->pos, len, ptr );
if ( ret <= 0 || ret > len )
{
ntfsUnlock( file->vd );
r->_errno = errno;
return -1;
}
ptr += ret;
len -= ret;
file->pos += ret;
read += ret;
}
//ntfs_log_trace("file->pos: %d \n", (u32)file->pos);
// Update file times (if we actually read something)
// Unlock
ntfsUnlock( file->vd );
return read;
}
off_t ntfs_seek_r ( struct _reent *r, int fd, off_t pos, int dir )
{
ntfs_log_trace( "fd %p, pos %Li, dir %i\n", fd, pos, dir );
ntfs_file_state* file = STATE( fd );
off_t position = 0;
// Sanity check
if ( !file || !file->vd || !file->ni || !file->data_na )
{
r->_errno = EINVAL;
return -1;
}
// Lock
ntfsLock( file->vd );
// Set the files current position
switch ( dir )
{
case SEEK_SET: position = file->pos = MIN( MAX( pos, 0 ), file->len ); break;
case SEEK_CUR: position = file->pos = MIN( MAX( file->pos + pos, 0 ), file->len ); break;
case SEEK_END: position = file->pos = MIN( MAX( file->len + pos, 0 ), file->len ); break;
}
// Unlock
ntfsUnlock( file->vd );
return position;
}
int ntfs_fstat_r ( struct _reent *r, int fd, struct stat *st )
{
ntfs_log_trace( "fd %p\n", fd );
ntfs_file_state* file = STATE( fd );
int ret = 0;
// Sanity check
if ( !file || !file->vd || !file->ni || !file->data_na )
{
r->_errno = EINVAL;
return -1;
}
// Short circuit cases were we don't actually have to do anything
if ( !st )
return 0;
// Get the file stats
ret = ntfsStat( file->vd, file->ni, st );
if ( ret )
r->_errno = errno;
return ret;
}
int ntfs_ftruncate_r ( struct _reent *r, int fd, off_t len )
{
ntfs_log_trace( "fd %p, len %Li\n", fd, len );
ntfs_file_state* file = STATE( fd );
// Sanity check
if ( !file || !file->vd || !file->ni || !file->data_na )
{
r->_errno = EINVAL;
return -1;
}
// Lock
ntfsLock( file->vd );
// Check that we are allowed to write to this file
if ( !file->write )
{
ntfsUnlock( file->vd );
r->_errno = EACCES;
return -1;
}
// For compressed files, only deleting and expanding contents are implemented
if ( file->compressed &&
len > 0 &&
len < file->data_na->initialized_size )
{
ntfsUnlock( file->vd );
r->_errno = EOPNOTSUPP;
return -1;
}
// Resize the files data attribute, either by expanding or truncating
if ( file->compressed && len > file->data_na->initialized_size )
{
char zero = 0;
if ( ntfs_attr_pwrite( file->data_na, len - 1, 1, &zero ) <= 0 )
{
ntfsUnlock( file->vd );
r->_errno = errno;
return -1;
}
}
else
{
if ( ntfs_attr_truncate( file->data_na, len ) )
{
ntfsUnlock( file->vd );
r->_errno = errno;
return -1;
}
}
// Mark the file for archiving (if we actually changed something)
if ( file->len != file->data_na->data_size )
file->ni->flags |= FILE_ATTR_ARCHIVE;
// Update file times (if we actually changed something)
if ( file->len != file->data_na->data_size )
ntfsUpdateTimes( file->vd, file->ni, NTFS_UPDATE_AMCTIME );
// Update the files data length
file->len = file->data_na->data_size;
// Sync the file (and its attributes) to disc
ntfsSync( file->vd, file->ni );
// Unlock
ntfsUnlock( file->vd );
return 0;
}
int ntfs_fsync_r ( struct _reent *r, int fd )
{
ntfs_log_trace( "fd %p\n", fd );
ntfs_file_state* file = STATE( fd );
int ret = 0;
// Sanity check
if ( !file || !file->vd || !file->ni || !file->data_na )
{
r->_errno = EINVAL;
return -1;
}
// Lock
ntfsLock( file->vd );
// Sync the file (and its attributes) to disc
ret = ntfsSync( file->vd, file->ni );
if ( ret )
r->_errno = errno;
// Unlock
ntfsUnlock( file->vd );
return ret;
}