/******************************************************************************
*
*
*
* Copyright (C) 1997-2001 by Dimitri van Heesch.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation under the terms of the GNU General Public License is hereby
* granted. No representations are made about the suitability of this software
* for any purpose. It is provided "as is" without express or implied warranty.
* See the GNU General Public License for more details.
*
* Documents produced by Doxygen are derivative works derived from the
* input used in their production; they are not affected by this license.
*
* Based on qfile_unix.cpp
*
* Copyright (C) 1992-2000 Trolltech AS.
*/
#include "qglobal.h"
#include "qfile.h"
#include "qfiledefs_p.h"
#if defined(_OS_MAC_) || defined(_OS_MSDOS_) || defined(_OS_WIN32_) || defined(_OS_OS2_)
# 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
static void reslashify( QString& n )
{
for ( int i=0; i<(int)n.length(); i++ )
{
if ( n[i] == '/' )
n[i] = '\\';
}
}
bool qt_file_access( const QString& fn, int t )
{
if ( fn.isEmpty() )
return FALSE;
#if defined(__CYGWIN32_)
return ACCESS( QFile::encodeName(fn), t ) == 0;
#else
QString str = fn;
reslashify(str);
return ( _waccess( (wchar_t*) str.ucs2(), t ) == 0 );
#endif
}
/*!
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;
}
#if defined(__CYGWIN32_)
// unlink more common in UNIX
return ::remove( QFile::encodeName(fileName) ) == 0;
#else
QString str = fileName;
reslashify(str);
return ( _wunlink( (wchar_t*) str.ucs2() ) == 0 );
#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
/*!
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() )
oflags |= OPEN_TEXT;
else
oflags |= OPEN_BINARY;
#endif
#if defined(HAS_ASYNC_FILEMODE)
if ( isAsynchronous() )
oflags |= OPEN_ASYNC;
#endif
#if defined(__CYGWIN32_)
fd = OPEN( QFile::encodeName(fn), oflags, 0666 );
#else
QString str = fn;
reslashify(str);
fd = _wopen( (wchar_t*) str.ucs2(), oflags, 0666 );
#endif
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 ( isTranslated() )
strcat( perm2, "t" );
else
strcat( perm2, "b" );
while (1) { // At most twice
#if defined(__CYGWIN32_)
fh = fopen( QFile::encodeName(fn), perm2 );
#else
QString str = fn;
QString prm( perm2 );
reslashify(str);
fh = _wfopen( (wchar_t*) str.ucs2(), (wchar_t*) prm.ucs2() );
#endif
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 ) {
// 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 ) {
// 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;
}
}
}
return TRUE;
}
/*!
Returns the file size.
\sa at()
*/
uint QFile::size() const
{
STATBUF st;
if ( isOpen() ) {
FSTAT( fh ? FILENO(fh) : fd, &st );
return st.st_size;
} else {
#if defined(__CYGWIN32_)
STAT( QFile::encodeName(fn), &st );
#else
QString str = fn;
reslashify(str);
#ifdef QT_LARGEFILE_SUPPORT
if ( _wstati64( (wchar_t*) str.ucs2(), &st ) != -1 ) {
#else
if ( _wstat( (wchar_t*) str.ucs2(), &st ) != -1 ) {
#endif
#endif
return st.st_size;
}
}
return 0;
}
/*!
\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; // number of bytes read
if ( isRaw() ) { // raw file
nread = READ( fd, p, len );
if ( len && nread <= 0 ) {
nread = 0;
setStatus(IO_ReadError);
}
} else { // buffered file
nread = fread( p, 1, len, 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
int nwritten; // number of bytes written
if ( isRaw() ) // raw file
nwritten = WRITE( fd, p, len );
else // buffered file
nwritten = 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, pos, SEEK_SET )!=-1;
}
return FALSE;
}