src/common/file.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        file.cpp
// Purpose:     wxFile - encapsulates low-level "file descriptor"
//              wxTempFile
// Author:      Vadim Zeitlin
// Modified by:
// Created:     29/01/98
// RCS-ID:      $Id$
// Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
// Licence:     wxWindows license
/////////////////////////////////////////////////////////////////////////////

// ----------------------------------------------------------------------------
// headers
// ----------------------------------------------------------------------------

#ifdef __GNUG__
    #pragma implementation "file.h"
#endif

// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"

#ifdef __BORLANDC__
  #pragma hdrstop
#endif

#ifndef WX_PRECOMP
  #include "wx/defs.h"
#endif

#if wxUSE_FILE

// standard
#if defined(__WXMSW__) && !defined(__GNUWIN32__) && !defined(__WXWINE__)
  #include  <io.h>

#ifndef __SALFORDC__
    #define   WIN32_LEAN_AND_MEAN
    #define   NOSERVICE
    #define   NOIME
    #define   NOATOM
    #define   NOGDI
    #define   NOGDICAPMASKS
    #define   NOMETAFILE
    #define   NOMINMAX
    #define   NOMSG
    #define   NOOPENFILE
    #define   NORASTEROPS
    #define   NOSCROLL
    #define   NOSOUND
    #define   NOSYSMETRICS
    #define   NOTEXTMETRIC
    #define   NOWH
    #define   NOCOMM
    #define   NOKANJI
    #define   NOCRYPT
    #define   NOMCX
#endif

    #include  <windows.h>     // for GetTempFileName
#elif (defined(__UNIX__) || defined(__GNUWIN32__))
    #include  <unistd.h>
    #ifdef __GNUWIN32__
        #include <windows.h>
    #endif
#elif (defined(__WXSTUBS__))
    // Have to ifdef this for different environments
    #include <io.h>
#elif (defined(__WXMAC__))
    int access( const char *path, int mode ) { return 0 ; }
    char* mktemp( char * path ) { return path ;}
    #include  <unistd.h>
    #include  <unix.h>
    #define   W_OK        2
    #define   R_OK        4
#else
    #error  "Please specify the header with file functions declarations."
#endif  //Win/UNIX

#include  <stdio.h>       // SEEK_xxx constants
#include  <fcntl.h>       // O_RDONLY &c

#ifndef __MWERKS__
    #include  <sys/types.h>   // needed for stat
    #include  <sys/stat.h>    // stat
#endif

// Microsoft compiler loves underscores, feed them to it
#ifdef  __VISUALC__
    // functions
    #define   open        _open
    #define   close       _close
    #define   read        _read
    #define   write       _write
    #define   lseek       _lseek
    #define   fsync       _commit
    #define   access      _access
    #define   eof         _eof

    // types
    #define   stat        _stat

    // constants

    #define   O_RDONLY    _O_RDONLY
    #define   O_WRONLY    _O_WRONLY
    #define   O_RDWR      _O_RDWR
    #define   O_EXCL      _O_EXCL
    #define   O_CREAT     _O_CREAT
    #define   O_BINARY    _O_BINARY

    #define   S_IFDIR     _S_IFDIR
    #define   S_IFREG     _S_IFREG
#else
    #define   tell(fd)    lseek(fd, 0, SEEK_CUR)
#endif  // VC++

#if defined(__BORLANDC__) || defined(_MSC_VER)
    #define   W_OK        2
    #define   R_OK        4
#endif

// there is no distinction between text and binary files under Unix
#ifdef    __UNIX__
    #define   O_BINARY    (0)
#endif  //__UNIX__

#ifdef __SALFORDC__
    #include <unix.h>
#endif

// wxWindows
#include  <wx/string.h>
#include  <wx/intl.h>
#include  <wx/file.h>
#include  <wx/log.h>

#ifndef MAX_PATH
    #define MAX_PATH 512
#endif

#ifdef __WXMAC__
    char gwxMacFileName[ MAX_PATH ] ;
    char gwxMacFileName2[ MAX_PATH ] ;
    char gwxMacFileName3[ MAX_PATH ] ;
#endif

// some broken compilers don't have 3rd argument in open() and creat()
#ifdef __SALFORDC__
    #define ACCESS(access)
    #define stat    _stat
#else // normal compiler
    #define ACCESS(access)  , (access)
#endif // Salford C

// ============================================================================
// implementation of wxFile
// ============================================================================

// ----------------------------------------------------------------------------
// static functions
// ----------------------------------------------------------------------------
bool wxFile::Exists(const wxChar *name)
{
    struct stat st;
#if wxUSE_UNICODE && wxMBFILES
    wxCharBuffer fname = wxConvFile.cWC2MB(name);

    return !access(fname, 0) &&
           !stat(MBSTRINGCAST fname, &st) &&
           (st.st_mode & S_IFREG);
#else
    return !access(name, 0) &&
           !stat((wxChar*) name, &st) &&
           (st.st_mode & S_IFREG);
#endif
}

bool wxFile::Access(const wxChar *name, OpenMode mode)
{
    int how = 0;

    switch ( mode ) {
        case read:
            how = R_OK;
            break;

        case write:
            how = W_OK;
            break;

        default:
            wxFAIL_MSG(_T("bad wxFile::Access mode parameter."));
    }

    return access(wxFNCONV(name), how) == 0;
}

// ----------------------------------------------------------------------------
// opening/closing
// ----------------------------------------------------------------------------

// ctors
wxFile::wxFile(const wxChar *szFileName, OpenMode mode)
{
    m_fd = fd_invalid;
    m_error = FALSE;

    Open(szFileName, mode);
}

// dtor
wxFile::~wxFile()
{
    Close();
}

// create the file, fail if it already exists and bOverwrite
bool wxFile::Create(const wxChar *szFileName, bool bOverwrite, int accessMode)
{
    // if bOverwrite we create a new file or truncate the existing one,
    // otherwise we only create the new file and fail if it already exists
    int fd = open(wxFNCONV(szFileName),
                  O_WRONLY | O_CREAT | (bOverwrite ? O_TRUNC : O_EXCL)
                  ACCESS(accessMode));

    if ( fd == -1 ) {
        wxLogSysError(_("can't create file '%s'"), szFileName);
        return FALSE;
    }
    else {
        Attach(fd);
        return TRUE;
    }
}

// open the file
bool wxFile::Open(const wxChar *szFileName, OpenMode mode, int accessMode)
{
    int flags = O_BINARY;

    switch ( mode ) {
        case read:
            flags |= O_RDONLY;
            break;

        case write:
            flags |= O_WRONLY | O_CREAT | O_TRUNC;
            break;

        case write_append:
            flags |= O_WRONLY | O_APPEND;
            break;

        case read_write:
            flags |= O_RDWR;
            break;
    }

    int fd = open(wxFNCONV(szFileName), flags ACCESS(accessMode));

    if ( fd == -1 ) {
        wxLogSysError(_("can't open file '%s'"), szFileName);
        return FALSE;
    }
    else {
        Attach(fd);
        return TRUE;
    }
}

// close
bool wxFile::Close()
{
    if ( IsOpened() ) {
        if ( close(m_fd) == -1 ) {
            wxLogSysError(_("can't close file descriptor %d"), m_fd);
            m_fd = fd_invalid;
            return FALSE;
        }
        else
            m_fd = fd_invalid;
    }

    return TRUE;
}

// ----------------------------------------------------------------------------
// read/write
// ----------------------------------------------------------------------------

// read
off_t wxFile::Read(void *pBuf, off_t nCount)
{
    wxCHECK( (pBuf != NULL) && IsOpened(), 0 );

#ifdef __MWERKS__
    int iRc = ::read(m_fd, (char*) pBuf, nCount);
#else
    int iRc = ::read(m_fd, pBuf, nCount);
#endif
    if ( iRc == -1 ) {
        wxLogSysError(_("can't read from file descriptor %d"), m_fd);
        return wxInvalidOffset;
    }
    else
        return (size_t)iRc;
}

// write
size_t wxFile::Write(const void *pBuf, size_t nCount)
{
    wxCHECK( (pBuf != NULL) && IsOpened(), 0 );

#ifdef __MWERKS__
    int iRc = ::write(m_fd, (const char*) pBuf, nCount);
#else
    int iRc = ::write(m_fd, pBuf, nCount);
#endif
    if ( iRc == -1 ) {
        wxLogSysError(_("can't write to file descriptor %d"), m_fd);
        m_error = TRUE;
        return 0;
    }
    else
        return iRc;
}

// flush
bool wxFile::Flush()
{
    if ( IsOpened() ) {
#if defined(__VISUALC__) || wxHAVE_FSYNC
        if ( fsync(m_fd) == -1 )
        {
            wxLogSysError(_("can't flush file descriptor %d"), m_fd);
            return FALSE;
        }
#else // no fsync
        // just do nothing
#endif // fsync
    }

    return TRUE;
}

// ----------------------------------------------------------------------------
// seek
// ----------------------------------------------------------------------------

// seek
off_t wxFile::Seek(off_t ofs, wxSeekMode mode)
{
    wxASSERT( IsOpened() );

    int flag = -1;
    switch ( mode ) {
        case wxFromStart:
            flag = SEEK_SET;
            break;

        case wxFromCurrent:
            flag = SEEK_CUR;
            break;

        case wxFromEnd:
            flag = SEEK_END;
            break;

        default:
            wxFAIL_MSG(_("unknown seek origin"));
    }

    int iRc = lseek(m_fd, ofs, flag);
    if ( iRc == -1 ) {
        wxLogSysError(_("can't seek on file descriptor %d"), m_fd);
        return wxInvalidOffset;
    }
    else
        return (off_t)iRc;
}

// get current off_t
off_t wxFile::Tell() const
{
    wxASSERT( IsOpened() );

    int iRc = tell(m_fd);
    if ( iRc == -1 ) {
        wxLogSysError(_("can't get seek position on file descriptor %d"), m_fd);
        return wxInvalidOffset;
    }
    else
        return (off_t)iRc;
}

// get current file length
off_t wxFile::Length() const
{
    wxASSERT( IsOpened() );

#ifdef __VISUALC__
    int iRc = _filelength(m_fd);
#else // !VC++
    int iRc = tell(m_fd);
    if ( iRc != -1 ) {
        // @ have to use const_cast :-(
        int iLen = ((wxFile *)this)->SeekEnd();
        if ( iLen != -1 ) {
            // restore old position
            if ( ((wxFile *)this)->Seek(iRc) == -1 ) {
                // error
                iLen = -1;
            }
        }

        iRc = iLen;
    }
#endif  // VC++

    if ( iRc == -1 ) {
        wxLogSysError(_("can't find length of file on file descriptor %d"), m_fd);
        return wxInvalidOffset;
    }
    else
        return (off_t)iRc;
}

// is end of file reached?
bool wxFile::Eof() const
{
    wxASSERT( IsOpened() );

    int iRc;

#if defined(__UNIX__) || defined(__GNUWIN32__) || defined( __MWERKS__ ) || defined(__SALFORDC__)
    // @@ this doesn't work, of course, on unseekable file descriptors
    off_t ofsCur = Tell(),
    ofsMax = Length();
    if ( ofsCur == wxInvalidOffset || ofsMax == wxInvalidOffset )
        iRc = -1;
    else
        iRc = ofsCur == ofsMax;
#else  // Windows and "native" compiler
    iRc = eof(m_fd);
#endif // Windows/Unix

    switch ( iRc ) {
        case 1:
            break;

        case 0:
            return FALSE;

        case -1:
            wxLogSysError(_("can't determine if the end of file is reached on \
                descriptor %d"), m_fd);
                break;

        default:
            wxFAIL_MSG(_("invalid eof() return value."));
    }

    return TRUE;
}

// ============================================================================
// implementation of wxTempFile
// ============================================================================

// ----------------------------------------------------------------------------
// construction
// ----------------------------------------------------------------------------
wxTempFile::wxTempFile(const wxString& strName)
{
    Open(strName);
}

bool wxTempFile::Open(const wxString& strName)
{
    m_strName = strName;

    // we want to create the file in the same directory as strName because
    // otherwise rename() in Commit() might not work (if the files are on
    // different partitions for example). Unfortunately, the only standard
    // (POSIX) temp file creation function tmpnam() can't do it.
#if defined(__UNIX__) || defined(__WXSTUBS__)|| defined( __WXMAC__ )
    static const wxChar *szMktempSuffix = _T("XXXXXX");
    m_strTemp << strName << szMktempSuffix;
    mktemp(MBSTRINGCAST m_strTemp.mb_str()); // will do because length doesn't change
#else // Windows
    wxString strPath;
    wxSplitPath(strName, &strPath, NULL, NULL);
    if ( strPath.IsEmpty() )
        strPath = _T('.');  // GetTempFileName will fail if we give it empty string
#ifdef __WIN32__
    if ( !GetTempFileName(strPath, _T("wx_"),0, m_strTemp.GetWriteBuf(MAX_PATH)) )
#else
        // Not sure why MSVC++ 1.5 header defines first param as BYTE - bug?
        if ( !GetTempFileName((BYTE) (const wxChar*) strPath, _T("wx_"),0, m_strTemp.GetWriteBuf(MAX_PATH)) )
#endif
            wxLogLastError(_T("GetTempFileName"));
    m_strTemp.UngetWriteBuf();
#endif  // Windows/Unix

    int access = wxS_DEFAULT;
#ifdef __UNIX__
    // create the file with the same mode as the original one under Unix
    mode_t umaskOld = 0; // just to suppress compiler warning
    bool changedUmask;

    struct stat st;
    if ( stat(strName.fn_str(), &st) == 0 )
    {
        // this assumes that only lower bits of st_mode contain the access
        // rights, but it's true for at least all Unices which have S_IXXXX()
        // macros, so should not be less portable than using (not POSIX)
        // S_IFREG &c
        access = st.st_mode & 0777;

        // we want to create the file with exactly the same access rights as
        // the original one, so disable the user's umask for the moment
        umaskOld = umask(0);
        changedUmask = TRUE;
    }
    else
    {
        // file probably didn't exist, just create with default mode _using_
        // user's umask (new files creation should respet umask)
        changedUmask = FALSE;
    }
#endif // Unix

    bool ok = m_file.Open(m_strTemp, wxFile::write, access);

#ifdef __UNIX__
    if ( changedUmask )
    {
        // restore umask now that the file is created
        (void)umask(umaskOld);
    }
#endif // Unix

    return ok;
}

// ----------------------------------------------------------------------------
// destruction
// ----------------------------------------------------------------------------

wxTempFile::~wxTempFile()
{
    if ( IsOpened() )
        Discard();
}

bool wxTempFile::Commit()
{
    m_file.Close();

    if ( wxFile::Exists(m_strName) && remove(m_strName.fn_str()) != 0 ) {
        wxLogSysError(_("can't remove file '%s'"), m_strName.c_str());
        return FALSE;
    }

    if ( rename(m_strTemp.fn_str(), m_strName.fn_str()) != 0 ) {
        wxLogSysError(_("can't commit changes to file '%s'"), m_strName.c_str());
        return FALSE;
    }

    return TRUE;
}

void wxTempFile::Discard()
{
    m_file.Close();
    if ( remove(m_strTemp.fn_str()) != 0 )
        wxLogSysError(_("can't remove temporary file '%s'"), m_strTemp.c_str());
}

#endif
Commit	Line	Data
	1	/////////////////////////////////////////////////////////////////////////////
	2	// Name: file.cpp
	3	// Purpose: wxFile - encapsulates low-level "file descriptor"
	4	// wxTempFile
	5	// Author: Vadim Zeitlin
	6	// Modified by:
	7	// Created: 29/01/98
	8	// RCS-ID: $Id$
	9	// Copyright: (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
	10	// Licence: wxWindows license
	11	/////////////////////////////////////////////////////////////////////////////
	12
	13	// ----------------------------------------------------------------------------
	14	// headers
	15	// ----------------------------------------------------------------------------
	16
	17	#ifdef __GNUG__
	18	#pragma implementation "file.h"
	19	#endif
	20
	21	// For compilers that support precompilation, includes "wx.h".
	22	#include "wx/wxprec.h"
	23
	24	#ifdef __BORLANDC__
	25	#pragma hdrstop
	26	#endif
	27
	28	#ifndef WX_PRECOMP
	29	#include "wx/defs.h"
	30	#endif
	31
	32	#if wxUSE_FILE
	33
	34	// standard
	35	#if defined(__WXMSW__) && !defined(__GNUWIN32__) && !defined(__WXWINE__)
	36	#include <io.h>
	37
	38	#ifndef __SALFORDC__
	39	#define WIN32_LEAN_AND_MEAN
	40	#define NOSERVICE
	41	#define NOIME
	42	#define NOATOM
	43	#define NOGDI
	44	#define NOGDICAPMASKS
	45	#define NOMETAFILE
	46	#define NOMINMAX
	47	#define NOMSG
	48	#define NOOPENFILE
	49	#define NORASTEROPS
	50	#define NOSCROLL
	51	#define NOSOUND
	52	#define NOSYSMETRICS
	53	#define NOTEXTMETRIC
	54	#define NOWH
	55	#define NOCOMM
	56	#define NOKANJI
	57	#define NOCRYPT
	58	#define NOMCX
	59	#endif
	60
	61	#include <windows.h> // for GetTempFileName
	62	#elif (defined(__UNIX__) \|\| defined(__GNUWIN32__))
	63	#include <unistd.h>
	64	#ifdef __GNUWIN32__
	65	#include <windows.h>
	66	#endif
	67	#elif (defined(__WXSTUBS__))
	68	// Have to ifdef this for different environments
	69	#include <io.h>
	70	#elif (defined(__WXMAC__))
	71	int access( const char *path, int mode ) { return 0 ; }
	72	char* mktemp( char * path ) { return path ;}
	73	#include <unistd.h>
	74	#include <unix.h>
	75	#define W_OK 2
	76	#define R_OK 4
	77	#else
	78	#error "Please specify the header with file functions declarations."
	79	#endif //Win/UNIX
	80
	81	#include <stdio.h> // SEEK_xxx constants
	82	#include <fcntl.h> // O_RDONLY &c
	83
	84	#ifndef __MWERKS__
	85	#include <sys/types.h> // needed for stat
	86	#include <sys/stat.h> // stat
	87	#endif
	88
	89	// Microsoft compiler loves underscores, feed them to it
	90	#ifdef __VISUALC__
	91	// functions
	92	#define open _open
	93	#define close _close
	94	#define read _read
	95	#define write _write
	96	#define lseek _lseek
	97	#define fsync _commit
	98	#define access _access
	99	#define eof _eof
	100
	101	// types
	102	#define stat _stat
	103
	104	// constants
	105
	106	#define O_RDONLY _O_RDONLY
	107	#define O_WRONLY _O_WRONLY
	108	#define O_RDWR _O_RDWR
	109	#define O_EXCL _O_EXCL
	110	#define O_CREAT _O_CREAT
	111	#define O_BINARY _O_BINARY
	112
	113	#define S_IFDIR _S_IFDIR
	114	#define S_IFREG _S_IFREG
	115	#else
	116	#define tell(fd) lseek(fd, 0, SEEK_CUR)
	117	#endif // VC++
	118
	119	#if defined(__BORLANDC__) \|\| defined(_MSC_VER)
	120	#define W_OK 2
	121	#define R_OK 4
	122	#endif
	123
	124	// there is no distinction between text and binary files under Unix
	125	#ifdef __UNIX__
	126	#define O_BINARY (0)
	127	#endif //__UNIX__
	128
	129	#ifdef __SALFORDC__
	130	#include <unix.h>
	131	#endif
	132
	133	// wxWindows
	134	#include <wx/string.h>
	135	#include <wx/intl.h>
	136	#include <wx/file.h>
	137	#include <wx/log.h>
	138
	139	#ifndef MAX_PATH
	140	#define MAX_PATH 512
	141	#endif
	142
	143	#ifdef __WXMAC__
	144	char gwxMacFileName[ MAX_PATH ] ;
	145	char gwxMacFileName2[ MAX_PATH ] ;
	146	char gwxMacFileName3[ MAX_PATH ] ;
	147	#endif
	148
	149	// some broken compilers don't have 3rd argument in open() and creat()
	150	#ifdef __SALFORDC__
	151	#define ACCESS(access)
	152	#define stat _stat
	153	#else // normal compiler
	154	#define ACCESS(access) , (access)
	155	#endif // Salford C
	156
	157	// ============================================================================
	158	// implementation of wxFile
	159	// ============================================================================
	160
	161	// ----------------------------------------------------------------------------
	162	// static functions
	163	// ----------------------------------------------------------------------------
	164	bool wxFile::Exists(const wxChar *name)
	165	{
	166	struct stat st;
	167	#if wxUSE_UNICODE && wxMBFILES
	168	wxCharBuffer fname = wxConvFile.cWC2MB(name);
	169
	170	return !access(fname, 0) &&
	171	!stat(MBSTRINGCAST fname, &st) &&
	172	(st.st_mode & S_IFREG);
	173	#else
	174	return !access(name, 0) &&
	175	!stat((wxChar*) name, &st) &&
	176	(st.st_mode & S_IFREG);
	177	#endif
	178	}
	179
	180	bool wxFile::Access(const wxChar *name, OpenMode mode)
	181	{
	182	int how = 0;
	183
	184	switch ( mode ) {
	185	case read:
	186	how = R_OK;
	187	break;
	188
	189	case write:
	190	how = W_OK;
	191	break;
	192
	193	default:
	194	wxFAIL_MSG(_T("bad wxFile::Access mode parameter."));
	195	}
	196
	197	return access(wxFNCONV(name), how) == 0;
	198	}
	199
	200	// ----------------------------------------------------------------------------
	201	// opening/closing
	202	// ----------------------------------------------------------------------------
	203
	204	// ctors
	205	wxFile::wxFile(const wxChar *szFileName, OpenMode mode)
	206	{
	207	m_fd = fd_invalid;
	208	m_error = FALSE;
	209
	210	Open(szFileName, mode);
	211	}
	212
	213	// dtor
	214	wxFile::~wxFile()
	215	{
	216	Close();
	217	}
	218
	219	// create the file, fail if it already exists and bOverwrite
	220	bool wxFile::Create(const wxChar *szFileName, bool bOverwrite, int accessMode)
	221	{
	222	// if bOverwrite we create a new file or truncate the existing one,
	223	// otherwise we only create the new file and fail if it already exists
	224	int fd = open(wxFNCONV(szFileName),
	225	O_WRONLY \| O_CREAT \| (bOverwrite ? O_TRUNC : O_EXCL)
	226	ACCESS(accessMode));
	227
	228	if ( fd == -1 ) {
	229	wxLogSysError(_("can't create file '%s'"), szFileName);
	230	return FALSE;
	231	}
	232	else {
	233	Attach(fd);
	234	return TRUE;
	235	}
	236	}
	237
	238	// open the file
	239	bool wxFile::Open(const wxChar *szFileName, OpenMode mode, int accessMode)
	240	{
	241	int flags = O_BINARY;
	242
	243	switch ( mode ) {
	244	case read:
	245	flags \|= O_RDONLY;
	246	break;
	247
	248	case write:
	249	flags \|= O_WRONLY \| O_CREAT \| O_TRUNC;
	250	break;
	251
	252	case write_append:
	253	flags \|= O_WRONLY \| O_APPEND;
	254	break;
	255
	256	case read_write:
	257	flags \|= O_RDWR;
	258	break;
	259	}
	260
	261	int fd = open(wxFNCONV(szFileName), flags ACCESS(accessMode));
	262
	263	if ( fd == -1 ) {
	264	wxLogSysError(_("can't open file '%s'"), szFileName);
	265	return FALSE;
	266	}
	267	else {
	268	Attach(fd);
	269	return TRUE;
	270	}
	271	}
	272
	273	// close
	274	bool wxFile::Close()
	275	{
	276	if ( IsOpened() ) {
	277	if ( close(m_fd) == -1 ) {
	278	wxLogSysError(_("can't close file descriptor %d"), m_fd);
	279	m_fd = fd_invalid;
	280	return FALSE;
	281	}
	282	else
	283	m_fd = fd_invalid;
	284	}
	285
	286	return TRUE;
	287	}
	288
	289	// ----------------------------------------------------------------------------
	290	// read/write
	291	// ----------------------------------------------------------------------------
	292
	293	// read
	294	off_t wxFile::Read(void *pBuf, off_t nCount)
	295	{
	296	wxCHECK( (pBuf != NULL) && IsOpened(), 0 );
	297
	298	#ifdef __MWERKS__
	299	int iRc = ::read(m_fd, (char*) pBuf, nCount);
	300	#else
	301	int iRc = ::read(m_fd, pBuf, nCount);
	302	#endif
	303	if ( iRc == -1 ) {
	304	wxLogSysError(_("can't read from file descriptor %d"), m_fd);
	305	return wxInvalidOffset;
	306	}
	307	else
	308	return (size_t)iRc;
	309	}
	310
	311	// write
	312	size_t wxFile::Write(const void *pBuf, size_t nCount)
	313	{
	314	wxCHECK( (pBuf != NULL) && IsOpened(), 0 );
	315
	316	#ifdef __MWERKS__
	317	int iRc = ::write(m_fd, (const char*) pBuf, nCount);
	318	#else
	319	int iRc = ::write(m_fd, pBuf, nCount);
	320	#endif
	321	if ( iRc == -1 ) {
	322	wxLogSysError(_("can't write to file descriptor %d"), m_fd);
	323	m_error = TRUE;
	324	return 0;
	325	}
	326	else
	327	return iRc;
	328	}
	329
	330	// flush
	331	bool wxFile::Flush()
	332	{
	333	if ( IsOpened() ) {
	334	#if defined(__VISUALC__) \|\| wxHAVE_FSYNC
	335	if ( fsync(m_fd) == -1 )
	336	{
	337	wxLogSysError(_("can't flush file descriptor %d"), m_fd);
	338	return FALSE;
	339	}
	340	#else // no fsync
	341	// just do nothing
	342	#endif // fsync
	343	}
	344
	345	return TRUE;
	346	}
	347
	348	// ----------------------------------------------------------------------------
	349	// seek
	350	// ----------------------------------------------------------------------------
	351
	352	// seek
	353	off_t wxFile::Seek(off_t ofs, wxSeekMode mode)
	354	{
	355	wxASSERT( IsOpened() );
	356
	357	int flag = -1;
	358	switch ( mode ) {
	359	case wxFromStart:
	360	flag = SEEK_SET;
	361	break;
	362
	363	case wxFromCurrent:
	364	flag = SEEK_CUR;
	365	break;
	366
	367	case wxFromEnd:
	368	flag = SEEK_END;
	369	break;
	370
	371	default:
	372	wxFAIL_MSG(_("unknown seek origin"));
	373	}
	374
	375	int iRc = lseek(m_fd, ofs, flag);
	376	if ( iRc == -1 ) {
	377	wxLogSysError(_("can't seek on file descriptor %d"), m_fd);
	378	return wxInvalidOffset;
	379	}
	380	else
	381	return (off_t)iRc;
	382	}
	383
	384	// get current off_t
	385	off_t wxFile::Tell() const
	386	{
	387	wxASSERT( IsOpened() );
	388
	389	int iRc = tell(m_fd);
	390	if ( iRc == -1 ) {
	391	wxLogSysError(_("can't get seek position on file descriptor %d"), m_fd);
	392	return wxInvalidOffset;
	393	}
	394	else
	395	return (off_t)iRc;
	396	}
	397
	398	// get current file length
	399	off_t wxFile::Length() const
	400	{
	401	wxASSERT( IsOpened() );
	402
	403	#ifdef __VISUALC__
	404	int iRc = _filelength(m_fd);
	405	#else // !VC++
	406	int iRc = tell(m_fd);
	407	if ( iRc != -1 ) {
	408	// @ have to use const_cast :-(
	409	int iLen = ((wxFile *)this)->SeekEnd();
	410	if ( iLen != -1 ) {
	411	// restore old position
	412	if ( ((wxFile *)this)->Seek(iRc) == -1 ) {
	413	// error
	414	iLen = -1;
	415	}
	416	}
	417
	418	iRc = iLen;
	419	}
	420	#endif // VC++
	421
	422	if ( iRc == -1 ) {
	423	wxLogSysError(_("can't find length of file on file descriptor %d"), m_fd);
	424	return wxInvalidOffset;
	425	}
	426	else
	427	return (off_t)iRc;
	428	}
	429
	430	// is end of file reached?
	431	bool wxFile::Eof() const
	432	{
	433	wxASSERT( IsOpened() );
	434
	435	int iRc;
	436
	437	#if defined(__UNIX__) \|\| defined(__GNUWIN32__) \|\| defined( __MWERKS__ ) \|\| defined(__SALFORDC__)
	438	// @@ this doesn't work, of course, on unseekable file descriptors
	439	off_t ofsCur = Tell(),
	440	ofsMax = Length();
	441	if ( ofsCur == wxInvalidOffset \|\| ofsMax == wxInvalidOffset )
	442	iRc = -1;
	443	else
	444	iRc = ofsCur == ofsMax;
	445	#else // Windows and "native" compiler
	446	iRc = eof(m_fd);
	447	#endif // Windows/Unix
	448
	449	switch ( iRc ) {
	450	case 1:
	451	break;
	452
	453	case 0:
	454	return FALSE;
	455
	456	case -1:
	457	wxLogSysError(_("can't determine if the end of file is reached on \
	458	descriptor %d"), m_fd);
	459	break;
	460
	461	default:
	462	wxFAIL_MSG(_("invalid eof() return value."));
	463	}
	464
	465	return TRUE;
	466	}
	467
	468	// ============================================================================
	469	// implementation of wxTempFile
	470	// ============================================================================
	471
	472	// ----------------------------------------------------------------------------
	473	// construction
	474	// ----------------------------------------------------------------------------
	475	wxTempFile::wxTempFile(const wxString& strName)
	476	{
	477	Open(strName);
	478	}
	479
	480	bool wxTempFile::Open(const wxString& strName)
	481	{
	482	m_strName = strName;
	483
	484	// we want to create the file in the same directory as strName because
	485	// otherwise rename() in Commit() might not work (if the files are on
	486	// different partitions for example). Unfortunately, the only standard
	487	// (POSIX) temp file creation function tmpnam() can't do it.
	488	#if defined(__UNIX__) \|\| defined(__WXSTUBS__)\|\| defined( __WXMAC__ )
	489	static const wxChar *szMktempSuffix = _T("XXXXXX");
	490	m_strTemp << strName << szMktempSuffix;
	491	mktemp(MBSTRINGCAST m_strTemp.mb_str()); // will do because length doesn't change
	492	#else // Windows
	493	wxString strPath;
	494	wxSplitPath(strName, &strPath, NULL, NULL);
	495	if ( strPath.IsEmpty() )
	496	strPath = _T('.'); // GetTempFileName will fail if we give it empty string
	497	#ifdef __WIN32__
	498	if ( !GetTempFileName(strPath, _T("wx_"),0, m_strTemp.GetWriteBuf(MAX_PATH)) )
	499	#else
	500	// Not sure why MSVC++ 1.5 header defines first param as BYTE - bug?
	501	if ( !GetTempFileName((BYTE) (const wxChar*) strPath, _T("wx_"),0, m_strTemp.GetWriteBuf(MAX_PATH)) )
	502	#endif
	503	wxLogLastError(_T("GetTempFileName"));
	504	m_strTemp.UngetWriteBuf();
	505	#endif // Windows/Unix
	506
	507	int access = wxS_DEFAULT;
	508	#ifdef __UNIX__
	509	// create the file with the same mode as the original one under Unix
	510	mode_t umaskOld = 0; // just to suppress compiler warning
	511	bool changedUmask;
	512
	513	struct stat st;
	514	if ( stat(strName.fn_str(), &st) == 0 )
	515	{
	516	// this assumes that only lower bits of st_mode contain the access
	517	// rights, but it's true for at least all Unices which have S_IXXXX()
	518	// macros, so should not be less portable than using (not POSIX)
	519	// S_IFREG &c
	520	access = st.st_mode & 0777;
	521
	522	// we want to create the file with exactly the same access rights as
	523	// the original one, so disable the user's umask for the moment
	524	umaskOld = umask(0);
	525	changedUmask = TRUE;
	526	}
	527	else
	528	{
	529	// file probably didn't exist, just create with default mode _using_
	530	// user's umask (new files creation should respet umask)
	531	changedUmask = FALSE;
	532	}
	533	#endif // Unix
	534
	535	bool ok = m_file.Open(m_strTemp, wxFile::write, access);
	536
	537	#ifdef __UNIX__
	538	if ( changedUmask )
	539	{
	540	// restore umask now that the file is created
	541	(void)umask(umaskOld);
	542	}
	543	#endif // Unix
	544
	545	return ok;
	546	}
	547
	548	// ----------------------------------------------------------------------------
	549	// destruction
	550	// ----------------------------------------------------------------------------
	551
	552	wxTempFile::~wxTempFile()
	553	{
	554	if ( IsOpened() )
	555	Discard();
	556	}
	557
	558	bool wxTempFile::Commit()
	559	{
	560	m_file.Close();
	561
	562	if ( wxFile::Exists(m_strName) && remove(m_strName.fn_str()) != 0 ) {
	563	wxLogSysError(_("can't remove file '%s'"), m_strName.c_str());
	564	return FALSE;
	565	}
	566
	567	if ( rename(m_strTemp.fn_str(), m_strName.fn_str()) != 0 ) {
	568	wxLogSysError(_("can't commit changes to file '%s'"), m_strName.c_str());
	569	return FALSE;
	570	}
	571
	572	return TRUE;
	573	}
	574
	575	void wxTempFile::Discard()
	576	{
	577	m_file.Close();
	578	if ( remove(m_strTemp.fn_str()) != 0 )
	579	wxLogSysError(_("can't remove temporary file '%s'"), m_strTemp.c_str());
	580	}
	581
	582	#endif