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author | dimitri <dimitri@afe2bf4a-e733-0410-8a33-86f594647bc7> | 2000-10-15 15:32:16 (GMT) |
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committer | dimitri <dimitri@afe2bf4a-e733-0410-8a33-86f594647bc7> | 2000-10-15 15:32:16 (GMT) |
commit | 868208ab61ca3aa6f506076f60de2745eaa8a6be (patch) | |
tree | 7824ba2a5c9f1fe6ddc8633a13cc7d1e7a6c79a3 /qtools/qfile_unix.cpp | |
parent | 499475795ed160e3a1e9cb571adc1ad86dc6a8ba (diff) | |
download | Doxygen-868208ab61ca3aa6f506076f60de2745eaa8a6be.zip Doxygen-868208ab61ca3aa6f506076f60de2745eaa8a6be.tar.gz Doxygen-868208ab61ca3aa6f506076f60de2745eaa8a6be.tar.bz2 |
Release-1.2.2-20001015
Diffstat (limited to 'qtools/qfile_unix.cpp')
-rw-r--r-- | qtools/qfile_unix.cpp | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/qtools/qfile_unix.cpp b/qtools/qfile_unix.cpp new file mode 100644 index 0000000..5c27988 --- /dev/null +++ b/qtools/qfile_unix.cpp @@ -0,0 +1,601 @@ +/**************************************************************************** +** +** +** 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" + +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() ) + oflags |= OPEN_TEXT; + 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() ) + strcat( perm2, "t" ); + 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 ) { + // 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 ); + } else { + STAT( QFile::encodeName(fn), &st ); + } + return 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; // 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; +} |