/****************************************************************************
**
**
** Implementation of QFileInfo class
**
** Created : 950628
**
** Copyright (C) 1992-2000 Trolltech AS. All rights reserved.
**
** This file is part of the tools module of the Qt GUI Toolkit.
**
** This file may be distributed under the terms of the Q Public License
** as defined by Trolltech AS of Norway and appearing in the file
** LICENSE.QPL included in the packaging of this file.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
** licenses for Unix/X11 or for Qt/Embedded may use this file in accordance
** with the Qt Commercial License Agreement provided with the Software.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
** information about Qt Commercial License Agreements.
** See http://www.trolltech.com/qpl/ for QPL licensing information.
** See http://www.trolltech.com/gpl/ for GPL licensing information.
**
** Contact info@trolltech.com if any conditions of this licensing are
** not clear to you.
**
**********************************************************************/
#include "qglobal.h"
#include "qfile.h"
#include "qfiledefs_p.h"
#if (defined(_OS_MAC_) && (!defined(_OS_UNIX_))) || defined(_OS_MSDOS_) || defined(_OS_WIN32_) || defined(_OS_OS2_) || defined(_OS_CYGWIN_)
# define HAS_TEXT_FILEMODE // has translate/text filemode
#endif
#if defined(O_NONBLOCK)
# define HAS_ASYNC_FILEMODE
# define OPEN_ASYNC O_NONBLOCK
#elif defined(O_NDELAY)
# define HAS_ASYNC_FILEMODE
# define OPEN_ASYNC O_NDELAY
#endif
bool qt_file_access( const QString& fn, int t )
{
if ( fn.isEmpty() )
return FALSE;
return ACCESS( QFile::encodeName(fn), t ) == 0;
}
/*!
Removes the file \a fileName.
Returns TRUE if successful, otherwise FALSE.
*/
bool QFile::remove( const QString &fileName )
{
if ( fileName.isEmpty() ) {
#if defined(CHECK_NULL)
qWarning( "QFile::remove: Empty or null file name" );
#endif
return FALSE;
}
return unlink( QFile::encodeName(fileName) ) == 0;
// unlink more common in UNIX
}
#if defined(O_NONBLOCK)
# define HAS_ASYNC_FILEMODE
# define OPEN_ASYNC O_NONBLOCK
#elif defined(O_NDELAY)
# define HAS_ASYNC_FILEMODE
# define OPEN_ASYNC O_NDELAY
#endif
/*!
Opens the file specified by the file name currently set, using the mode \e m.
Returns TRUE if successful, otherwise FALSE.
The mode parameter \e m must be a combination of the following flags:
<ul>
<li>\c IO_Raw specified raw (non-buffered) file access.
<li>\c IO_ReadOnly opens the file in read-only mode.
<li>\c IO_WriteOnly opens the file in write-only mode (and truncates).
<li>\c IO_ReadWrite opens the file in read/write mode, equivalent to
\c (IO_ReadOnly|IO_WriteOnly).
<li>\c IO_Append opens the file in append mode. This mode is very useful
when you want to write something to a log file. The file index is set to
the end of the file. Note that the result is undefined if you position the
file index manually using at() in append mode.
<li>\c IO_Truncate truncates the file.
<li>\c IO_Translate enables carriage returns and linefeed translation
for text files under MS-DOS, Windows and OS/2.
</ul>
The raw access mode is best when I/O is block-operated using 4kB block size
or greater. Buffered access works better when reading small portions of
data at a time.
<strong>Important:</strong> When working with buffered files, data may
not be written to the file at once. Call \link flush() flush\endlink
to make sure the data is really written.
\warning We have experienced problems with some C libraries when a buffered
file is opened for both reading and writing. If a read operation takes place
immediately after a write operation, the read buffer contains garbage data.
Worse, the same garbage is written to the file. Calling flush() before
readBlock() solved this problem.
If the file does not exist and \c IO_WriteOnly or \c IO_ReadWrite is
specified, it is created.
Example:
\code
QFile f1( "/tmp/data.bin" );
QFile f2( "readme.txt" );
f1.open( IO_Raw | IO_ReadWrite | IO_Append );
f2.open( IO_ReadOnly | IO_Translate );
\endcode
\sa name(), close(), isOpen(), flush()
*/
bool QFile::open( int m )
{
if ( isOpen() ) { // file already open
#if defined(CHECK_STATE)
qWarning( "QFile::open: File already open" );
#endif
return FALSE;
}
if ( fn.isNull() ) { // no file name defined
#if defined(CHECK_NULL)
qWarning( "QFile::open: No file name specified" );
#endif
return FALSE;
}
init(); // reset params
setMode( m );
if ( !(isReadable() || isWritable()) ) {
#if defined(CHECK_RANGE)
qWarning( "QFile::open: File access not specified" );
#endif
return FALSE;
}
bool ok = TRUE;
STATBUF st;
if ( isRaw() ) { // raw file I/O
int oflags = OPEN_RDONLY;
if ( isReadable() && isWritable() )
oflags = OPEN_RDWR;
else if ( isWritable() )
oflags = OPEN_WRONLY;
if ( flags() & IO_Append ) { // append to end of file?
if ( flags() & IO_Truncate )
oflags |= (OPEN_CREAT | OPEN_TRUNC);
else
oflags |= (OPEN_APPEND | OPEN_CREAT);
setFlags( flags() | IO_WriteOnly ); // append implies write
} else if ( isWritable() ) { // create/trunc if writable
if ( flags() & IO_Truncate )
oflags |= (OPEN_CREAT | OPEN_TRUNC);
else
oflags |= OPEN_CREAT;
}
#if defined(HAS_TEXT_FILEMODE)
if ( isTranslated() )
#ifdef __CYGWIN__
/* Do nothing, allowing the Cygwin mount mode to take effect. */;
#else
oflags |= OPEN_TEXT;
#endif
else
oflags |= OPEN_BINARY;
#endif
#if defined(HAS_ASYNC_FILEMODE)
if ( isAsynchronous() )
oflags |= OPEN_ASYNC;
#endif
fd = OPEN( QFile::encodeName(fn), oflags, 0666 );
if ( fd != -1 ) { // open successful
FSTAT( fd, &st ); // get the stat for later usage
} else {
ok = FALSE;
}
} else { // buffered file I/O
QCString perm;
char perm2[4];
bool try_create = FALSE;
if ( flags() & IO_Append ) { // append to end of file?
setFlags( flags() | IO_WriteOnly ); // append implies write
perm = isReadable() ? "a+" : "a";
} else {
if ( isReadWrite() ) {
if ( flags() & IO_Truncate ) {
perm = "w+";
} else {
perm = "r+";
try_create = TRUE; // try to create if not exists
}
} else if ( isReadable() ) {
perm = "r";
} else if ( isWritable() ) {
perm = "w";
}
}
qstrcpy( perm2, perm );
#if defined(HAS_TEXT_FILEMODE)
if ( isTranslated() )
#ifdef __CYGWIN__
/* Do nothing, allowing the Cygwin mount mode to take effect. */;
#else
strcat( perm2, "t" );
#endif
else
strcat( perm2, "b" );
#endif
while (1) { // At most twice
fh = fopen( QFile::encodeName(fn), perm2 );
if ( !fh && try_create ) {
perm2[0] = 'w'; // try "w+" instead of "r+"
try_create = FALSE;
} else {
break;
}
}
if ( fh ) {
FSTAT( FILENO(fh), &st ); // get the stat for later usage
} else {
ok = FALSE;
}
}
if ( ok ) {
setState( IO_Open );
// on successful open the file stat was got; now test what type
// of file we have
if ( (st.st_mode & STAT_MASK) != STAT_REG ) {
// non-seekable
setType( IO_Sequential );
length = INT_MAX;
ioIndex = (flags() & IO_Append) == 0 ? 0 : length;
} else {
length = (int)st.st_size;
ioIndex = (flags() & IO_Append) == 0 ? 0 : length;
if ( !(flags()&IO_Truncate) && length == 0 && isReadable() ) {
// try if you can read from it (if you can, it's a sequential
// device; e.g. a file in the /proc filesystem)
int c = getch();
if ( c != -1 ) {
ungetch(c);
setType( IO_Sequential );
length = INT_MAX;
}
}
}
} else {
init();
if ( errno == EMFILE ) // no more file handles/descrs
setStatus( IO_ResourceError );
else
setStatus( IO_OpenError );
}
return ok;
}
/*!
Opens a file in the mode \e m using an existing file handle \e f.
Returns TRUE if successful, otherwise FALSE.
Example:
\code
#include <stdio.h>
void printError( const char* msg )
{
QFile f;
f.open( IO_WriteOnly, stderr );
f.writeBlock( msg, qstrlen(msg) ); // write to stderr
f.close();
}
\endcode
When a QFile is opened using this function, close() does not actually
close the file, only flushes it.
\warning If \e f is \c stdin, \c stdout, \c stderr, you may not
be able to seek. See QIODevice::isSequentialAccess() for more
information.
\sa close()
*/
bool QFile::open( int m, FILE *f )
{
if ( isOpen() ) {
#if defined(CHECK_RANGE)
qWarning( "QFile::open: File already open" );
#endif
return FALSE;
}
init();
setMode( m &~IO_Raw );
setState( IO_Open );
fh = f;
ext_f = TRUE;
STATBUF st;
FSTAT( FILENO(fh), &st );
ioIndex = (int)ftell( fh );
if ( (st.st_mode & STAT_MASK) != STAT_REG || f == stdin ) { //stdin is non seekable
// non-seekable
setType( IO_Sequential );
length = INT_MAX;
} else {
length = (int)st.st_size;
if ( !(flags()&IO_Truncate) && length == 0 && isReadable() ) {
// try if you can read from it (if you can, it's a sequential
// device; e.g. a file in the /proc filesystem)
int c = getch();
if ( c != -1 ) {
ungetch(c);
setType( IO_Sequential );
length = INT_MAX;
}
}
}
return TRUE;
}
/*!
Opens a file in the mode \e m using an existing file descriptor \e f.
Returns TRUE if successful, otherwise FALSE.
When a QFile is opened using this function, close() does not actually
close the file.
\warning If \e f is one of 0 (stdin), 1 (stdout) or 2 (stderr), you may not
be able to seek. size() is set to \c INT_MAX (in limits.h).
\sa close()
*/
bool QFile::open( int m, int f )
{
if ( isOpen() ) {
#if defined(CHECK_RANGE)
qWarning( "QFile::open: File already open" );
#endif
return FALSE;
}
init();
setMode( m |IO_Raw );
setState( IO_Open );
fd = f;
ext_f = TRUE;
STATBUF st;
FSTAT( fd, &st );
ioIndex = (int)LSEEK(fd, 0, SEEK_CUR);
if ( (st.st_mode & STAT_MASK) != STAT_REG || f == 0 ) { // stdin is not seekable...
// non-seekable
setType( IO_Sequential );
length = INT_MAX;
} else {
length = (int)st.st_size;
if ( length == 0 && isReadable() ) {
// try if you can read from it (if you can, it's a sequential
// device; e.g. a file in the /proc filesystem)
int c = getch();
if ( c != -1 ) {
ungetch(c);
setType( IO_Sequential );
length = INT_MAX;
}
resetStatus();
}
}
return TRUE;
}
/*!
Returns the file size.
\sa at()
*/
uint QFile::size() const
{
STATBUF st;
if ( isOpen() ) {
FSTAT( fh ? FILENO(fh) : fd, &st );
} else {
STAT( QFile::encodeName(fn), &st );
}
return (uint)st.st_size;
}
/*!
\fn int QFile::at() const
Returns the file index.
\sa size()
*/
/*!
Sets the file index to \e pos. Returns TRUE if successful, otherwise FALSE.
Example:
\code
QFile f( "data.bin" );
f.open( IO_ReadOnly ); // index set to 0
f.at( 100 ); // set index to 100
f.at( f.at()+50 ); // set index to 150
f.at( f.size()-80 ); // set index to 80 before EOF
f.close();
\endcode
\warning The result is undefined if the file was \link open() opened\endlink
using the \c IO_Append specifier.
\sa size(), open()
*/
bool QFile::at( int pos )
{
if ( !isOpen() ) {
#if defined(CHECK_STATE)
qWarning( "QFile::at: File is not open" );
#endif
return FALSE;
}
bool ok;
if ( isRaw() ) { // raw file
pos = (int)LSEEK(fd, pos, SEEK_SET);
ok = pos != -1;
} else { // buffered file
ok = fseek(fh, pos, SEEK_SET) == 0;
}
if ( ok )
ioIndex = pos;
#if defined(CHECK_RANGE)
else
qWarning( "QFile::at: Cannot set file position %d", pos );
#endif
return ok;
}
/*!
Reads at most \e len bytes from the file into \e p and returns the
number of bytes actually read.
Returns -1 if a serious error occurred.
\warning We have experienced problems with some C libraries when a buffered
file is opened for both reading and writing. If a read operation takes place
immediately after a write operation, the read buffer contains garbage data.
Worse, the same garbage is written to the file. Calling flush() before
readBlock() solved this problem.
\sa writeBlock()
*/
int QFile::readBlock( char *p, uint len )
{
#if defined(CHECK_NULL)
if ( !p )
qWarning( "QFile::readBlock: Null pointer error" );
#endif
#if defined(CHECK_STATE)
if ( !isOpen() ) { // file not open
qWarning( "QFile::readBlock: File not open" );
return -1;
}
if ( !isReadable() ) { // reading not permitted
qWarning( "QFile::readBlock: Read operation not permitted" );
return -1;
}
#endif
int nread = 0; // number of bytes read
if ( !ungetchBuffer.isEmpty() ) {
// need to add these to the returned string.
int l = ungetchBuffer.length();
while( nread < l ) {
*p = ungetchBuffer[ l - nread - 1 ];
p++;
nread++;
}
ungetchBuffer.truncate( l - nread );
}
if ( nread < (int)len ) {
if ( isRaw() ) { // raw file
nread += (int)READ( fd, p, len-nread );
if ( len && nread <= 0 ) {
nread = 0;
setStatus(IO_ReadError);
}
} else { // buffered file
nread += (int)fread( p, 1, len-nread, fh );
if ( (uint)nread != len ) {
if ( ferror( fh ) || nread==0 )
setStatus(IO_ReadError);
}
}
}
ioIndex += nread;
return nread;
}
/*! \overload int writeBlock( const QByteArray& data )
*/
/*! \reimp
Writes \e len bytes from \e p to the file and returns the number of
bytes actually written.
Returns -1 if a serious error occurred.
\warning When working with buffered files, data may not be written
to the file at once. Call flush() to make sure the data is really
written.
\sa readBlock()
*/
int QFile::writeBlock( const char *p, uint len )
{
#if defined(CHECK_NULL)
if ( p == 0 && len != 0 )
qWarning( "QFile::writeBlock: Null pointer error" );
#endif
#if defined(CHECK_STATE)
if ( !isOpen() ) { // file not open
qWarning( "QFile::writeBlock: File not open" );
return -1;
}
if ( !isWritable() ) { // writing not permitted
qWarning( "QFile::writeBlock: Write operation not permitted" );
return -1;
}
#endif
if (p==0) return 0;
int nwritten; // number of bytes written
if ( isRaw() ) // raw file
nwritten = (int)WRITE( fd, p, len );
else // buffered file
nwritten = (int)fwrite( p, 1, len, fh );
if ( nwritten != (int)len ) { // write error
if ( errno == ENOSPC ) // disk is full
setStatus( IO_ResourceError );
else
setStatus( IO_WriteError );
if ( isRaw() ) // recalc file position
ioIndex = (int)LSEEK( fd, 0, SEEK_CUR );
else
ioIndex = fseek( fh, 0, SEEK_CUR );
} else {
ioIndex += nwritten;
}
if ( ioIndex > length ) // update file length
length = ioIndex;
return nwritten;
}
/*!
Returns the file handle of the file.
This is a small positive integer, suitable for use with C library
functions such as fdopen() and fcntl(), as well as with QSocketNotifier.
If the file is not open or there is an error, handle() returns -1.
\sa QSocketNotifier
*/
int QFile::handle() const
{
if ( !isOpen() )
return -1;
else if ( fh )
return FILENO( fh );
else
return fd;
}
/*!
Closes an open file.
The file is not closed if it was opened with an existing file handle.
If the existing file handle is a \c FILE*, the file is flushed.
If the existing file handle is an \c int file descriptor, nothing
is done to the file.
Some "write-behind" filesystems may report an unspecified error on
closing the file. These errors only indicate that something may
have gone wrong since the previous open(). In such a case status()
reports IO_UnspecifiedError after close(), otherwise IO_Ok.
\sa open(), flush()
*/
void QFile::close()
{
bool ok = FALSE;
if ( isOpen() ) { // file is not open
if ( fh ) { // buffered file
if ( ext_f )
ok = fflush( fh ) != -1; // flush instead of closing
else
ok = fclose( fh ) != -1;
} else { // raw file
if ( ext_f )
ok = TRUE; // cannot close
else
ok = CLOSE( fd ) != -1;
}
init(); // restore internal state
}
if (!ok)
setStatus (IO_UnspecifiedError);
return;
}
int64 QFile::pos() const
{
if (isOpen())
{
// TODO: support 64 bit size
return ftell( fh );
}
return -1;
}
int64 QFile::toEnd()
{
if (isOpen())
{
// TODO: support 64 bit size
if (fseek( fh, 0, SEEK_END )!=-1)
{
return ftell( fh );
}
}
return -1;
}
bool QFile::seek( int64 pos )
{
if (isOpen())
{
// TODO: support 64 bit size
return fseek( fh, (long)pos, SEEK_SET )!=-1;
}
return FALSE;
}