2020-09-30 17:12:29 +02:00

887 lines
21 KiB
C

/***
*open.c - file open
*
* Copyright (c) 1989-1995, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines _open() and _sopen() - open or create a file
*
*Revision History:
* 06-13-89 PHG Module created, based on asm version
* 11-11-89 JCR Replaced DOS32QUERYFILEMODE with DOS32QUERYPATHINFO
* 03-13-90 GJF Made calling type _CALLTYPE2 (for now), added #include
* <cruntime.h>, fixed some compiler warnings and fixed
* copyright. Also, cleaned up the formatting a bit.
* 07-24-90 SBM Removed '32' from API names
* 08-14-90 SBM Compiles cleanly with -W3
* 09-07-90 SBM Added stdarg code (inside #if 0..#endif) to make
* open and sopen match prototypes. Test and use this
* someday.
* 10-01-90 GJF New-style function declarators.
* 11-16-90 GJF Wrote version for Win32 API and appended it via an
* #ifdef. The Win32 version is similar to the old DOS
* version (though in C) and far different from either
* the Cruiser or OS/2 versions.
* 12-03-90 GJF Fixed a dozen or so minor errors in the Win32 version.
* 12-06-90 SRW Changed to use _osfile and _osfhnd instead of _osfinfo
* 12-28-90 SRW Added cast of void * to char * for Mips C Compiler
* 12-31-90 SRW Fixed spen to call CreateFile instead of OpenFile
* 01-16-91 GJF ANSI naming.
* 02-07-91 SRW Changed to call _get_osfhandle [_WIN32_]
* 02-19-91 SRW Adapt to OpenFile/CreateFile changes [_WIN32_]
* 02-25-91 SRW Renamed _get_free_osfhnd to be _alloc_osfhnd [_WIN32_]
* 04-09-91 PNT Added _MAC_ conditional
* 07-10-91 GJF Store fileflags into _osfile array before call to
* _lseek_lk (bug found by LarryO) [_WIN32_].
* 01-02-92 GJF Fixed Win32 version (not Cruiser!) so that pmode is not
* referenced unless _O_CREAT has been specified.
* 02-04-92 GJF Make better use of CreateFile options.
* 04-06-92 SRW Pay attention to _O_NOINHERIT flag in oflag parameter
* 05-02-92 SRW Add support for _O_TEMPORARY flag in oflag parameter.
* Causes FILE_ATTRIBUTE_TEMPORARY flag to be set in call
* to the Win32 CreateFile API.
* 07-01-92 GJF Close handle in case of error. Also, don't try to set
* FRDONLY bit anymore - no longer needed/used. [_WIN32_].
* 01-03-93 SRW Fix va_arg/va_end usage
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* 05-24-93 PML Add support for _O_SEQUENTIAL, _O_RANDOM,
* and _O_SHORT_LIVED
* 07-12-93 GJF Fixed bug in reading last char in text file. Also,use
* proper SEEK constants in _lseek_lk calls.
* 11-01-93 CFW Enable Unicode variant, rip out CRUISER.
* 02-15-95 GJF Appended Mac version of source file (somewhat cleaned
* up), with appropriate #ifdef-s.
* 06-06-95 CFW Enable shared writing.
* 06-12-95 GJF Replaced _osfile[] with _osfile() (macro referencing
* field in ioinfo struct).
*
*******************************************************************************/
#ifdef _WIN32
#include <cruntime.h>
#include <oscalls.h>
#include <msdos.h>
#include <errno.h>
#include <fcntl.h>
#include <internal.h>
#include <io.h>
#include <share.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys\types.h>
#include <sys\stat.h>
#include <mtdll.h>
#include <stdarg.h>
#include <tchar.h>
/***
*int _open(path, flag, pmode) - open or create a file
*
*Purpose:
* Opens the file and prepares for subsequent reading or writing.
* the flag argument specifies how to open the file:
* _O_APPEND - reposition file ptr to end before every write
* _O_BINARY - open in binary mode
* _O_CREAT - create a new file* no effect if file already exists
* _O_EXCL - return error if file exists, only use with O_CREAT
* _O_RDONLY - open for reading only
* _O_RDWR - open for reading and writing
* _O_TEXT - open in text mode
* _O_TRUNC - open and truncate to 0 length (must have write permission)
* _O_WRONLY - open for writing only
* _O_NOINHERIT -handle will not be inherited by child processes.
* exactly one of _O_RDONLY, _O_WRONLY, _O_RDWR must be given
*
* The pmode argument is only required when _O_CREAT is specified. Its
* flag settings:
* _S_IWRITE - writing permitted
* _S_IREAD - reading permitted
* _S_IREAD | _S_IWRITE - both reading and writing permitted
* The current file-permission maks is applied to pmode before
* setting the permission (see umask).
*
* The oflag and mode parameter have different meanings under DOS. See
* the A_xxx attributes in msdos.inc
*
* Note, the _creat() function also uses this function but setting up the
* correct arguments and calling _open(). _creat() sets the __creat_flag
* to 1 prior to calling _open() so _open() can return correctly. _open()
* returns the file handle in eax in this case.
*
*Entry:
* _TSCHAR *path - file name
* int flag - flags for _open()
* int pmode - permission mode for new files
*
*Exit:
* returns file handle of open file if successful
* returns -1 (and sets errno) if fails
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _topen (
const _TSCHAR *path,
int oflag,
...
)
{
va_list ap;
int pmode;
va_start(ap, oflag);
pmode = va_arg(ap, int);
va_end(ap);
/* default sharing mode is DENY NONE */
return _tsopen(path, oflag, _SH_DENYNO, pmode);
}
/***
*int _sopen(path, oflag, shflag, pmode) - opne a file with sharing
*
*Purpose:
* Opens the file with possible file sharing.
* shflag defines the sharing flags:
* _SH_COMPAT - set compatability mode
* _SH_DENYRW - deny read and write access to the file
* _SH_DENYWR - deny write access to the file
* _SH_DENYRD - deny read access to the file
* _SH_DENYNO - permit read and write access
*
* Other flags are the same as _open().
*
* SOPEN is the routine used when file sharing is desired.
*
*Entry:
* _TSCHAR *path - file to open
* int oflag - open flag
* int shflag - sharing flag
* int pmode - permission mode (needed only when creating file)
*
*Exit:
* returns file handle for the opened file
* returns -1 and sets errno if fails.
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _tsopen (
const _TSCHAR *path,
int oflag,
int shflag,
...
)
{
int fh; /* handle of opened file */
int filepos; /* length of file - 1 */
_TSCHAR ch; /* character at end of file */
char fileflags; /* _osfile flags */
va_list ap; /* variable argument (pmode) */
int pmode;
HANDLE osfh; /* OS handle of opened file */
DWORD fileaccess; /* OS file access (requested) */
DWORD fileshare; /* OS file sharing mode */
DWORD filecreate; /* OS method of opening/creating */
DWORD fileattrib; /* OS file attribute flags */
DWORD isdev; /* device indicator in low byte */
SECURITY_ATTRIBUTES SecurityAttributes;
SecurityAttributes.nLength = sizeof( SecurityAttributes );
SecurityAttributes.lpSecurityDescriptor = NULL;
if (oflag & _O_NOINHERIT) {
SecurityAttributes.bInheritHandle = FALSE;
}
else {
SecurityAttributes.bInheritHandle = TRUE;
}
/* figure out binary/text mode */
if (oflag & _O_BINARY)
fileflags = 0;
else if (oflag & _O_TEXT)
fileflags = (_TSCHAR)FTEXT;
else if (_fmode == _O_BINARY) /* check default mode */
fileflags = 0;
else
fileflags = (_TSCHAR)FTEXT;
/*
* decode the access flags
*/
switch( oflag & (_O_RDONLY | _O_WRONLY | _O_RDWR) ) {
case _O_RDONLY: /* read access */
fileaccess = GENERIC_READ;
break;
case _O_WRONLY: /* write access */
fileaccess = GENERIC_WRITE;
break;
case _O_RDWR: /* read and write access */
fileaccess = GENERIC_READ | GENERIC_WRITE;
break;
default: /* error, bad oflag */
errno = EINVAL;
_doserrno = 0L; /* not an OS error */
return -1;
}
/*
* decode sharing flags
*/
switch ( shflag ) {
case _SH_DENYRW: /* exclusive access */
fileshare = 0L;
break;
case _SH_DENYWR: /* share read access */
fileshare = FILE_SHARE_READ;
break;
case _SH_DENYRD: /* share write access */
fileshare = FILE_SHARE_WRITE;
break;
case _SH_DENYNO: /* share read and write access */
fileshare = FILE_SHARE_READ | FILE_SHARE_WRITE;
break;
default: /* error, bad shflag */
errno = EINVAL;
_doserrno = 0L; /* not an OS error */
return -1;
}
/*
* decode open/create method flags
*/
switch ( oflag & (_O_CREAT | _O_EXCL | _O_TRUNC) ) {
case 0:
case _O_EXCL: // ignore EXCL w/o CREAT
filecreate = OPEN_EXISTING;
break;
case _O_CREAT:
filecreate = OPEN_ALWAYS;
break;
case _O_CREAT | _O_EXCL:
case _O_CREAT | _O_TRUNC | _O_EXCL:
filecreate = CREATE_NEW;
break;
case _O_TRUNC:
case _O_TRUNC | _O_EXCL: // ignore EXCL w/o CREAT
filecreate = TRUNCATE_EXISTING;
break;
case _O_CREAT | _O_TRUNC:
filecreate = CREATE_ALWAYS;
break;
default:
// this can't happen ... all cases are covered
errno = EINVAL;
_doserrno = 0L;
return -1;
}
/*
* decode file attribute flags if _O_CREAT was specified
*/
fileattrib = FILE_ATTRIBUTE_NORMAL; /* default */
if ( oflag & _O_CREAT ) {
/*
* set up variable argument list stuff
*/
va_start(ap, shflag);
pmode = va_arg(ap, int);
va_end(ap);
if ( !((pmode & ~_umaskval) & _S_IWRITE) )
fileattrib = FILE_ATTRIBUTE_READONLY;
}
/*
* Set temporary file (delete-on-close) attribute if requested.
*/
if ( oflag & _O_TEMPORARY ) {
fileattrib |= FILE_FLAG_DELETE_ON_CLOSE;
fileaccess |= DELETE;
}
/*
* Set temporary file (delay-flush-to-disk) attribute if requested.
*/
if ( oflag & _O_SHORT_LIVED )
fileattrib |= FILE_ATTRIBUTE_TEMPORARY;
/*
* Set sequential or random access attribute if requested.
*/
if ( oflag & _O_SEQUENTIAL )
fileattrib |= FILE_FLAG_SEQUENTIAL_SCAN;
else if ( oflag & _O_RANDOM )
fileattrib |= FILE_FLAG_RANDOM_ACCESS;
/*
* get an available handle.
*
* multi-thread note: the returned handle is locked!
*/
if ( (fh = _alloc_osfhnd()) == -1 ) {
errno = EMFILE; /* too many open files */
_doserrno = 0L; /* not an OS error */
return -1; /* return error to caller */
}
/*
* try to open/create the file
*/
if ( (osfh = CreateFile((LPTSTR)path,
fileaccess,
fileshare,
&SecurityAttributes,
filecreate,
fileattrib,
NULL
))
== (HANDLE)0xffffffff ) {
/*
* OS call to open/create file failed! map the error, release
* the lock, and return -1. note that it's not necessary to
* call _free_osfhnd (it hasn't been used yet).
*/
_dosmaperr(GetLastError()); /* map error */
_unlock_fh(fh);
return -1; /* return error to caller */
}
/* find out what type of file (file/device/pipe) */
if ( (isdev = GetFileType(osfh)) == FILE_TYPE_UNKNOWN ) {
CloseHandle(osfh);
_dosmaperr(GetLastError()); /* map error */
_unlock_fh(fh);
return -1;
}
/* is isdev value to set flags */
if (isdev == FILE_TYPE_CHAR)
fileflags |= FDEV;
else if (isdev == FILE_TYPE_PIPE)
fileflags |= FPIPE;
/*
* the file is open. now, set the info in _osfhnd array
*/
_set_osfhnd(fh, (long)osfh);
/*
* mark the handle as open. store flags gathered so far in _osfile
* array.
*/
fileflags |= FOPEN;
_osfile(fh) = fileflags;
if (!(fileflags & (FDEV|FPIPE)) && (fileflags & FTEXT) &&
(oflag & _O_RDWR)) {
/* We have a text mode file. If it ends in CTRL-Z, we wish to
remove the CTRL-Z character, so that appending will work.
We do this by seeking to the end of file, reading the last
byte, and shortening the file if it is a CTRL-Z. */
if ((filepos = _lseek_lk(fh, -1, SEEK_END)) == -1) {
/* OS error -- should ignore negative seek error,
since that means we had a zero-length file. */
if (_doserrno != ERROR_NEGATIVE_SEEK) {
_close(fh);
_unlock_fh(fh);
return -1;
}
}
else {
/* Seek was OK, read the last char in file. The last
char is a CTRL-Z if and only if _read returns 0
and ch ends up with a CTRL-Z. */
ch = 0;
if (_read_lk(fh, &ch, 1) == 0 && ch == 26) {
/* read was OK and we got CTRL-Z! Wipe it
out! */
if (_chsize_lk(fh,filepos) == -1)
{
_close(fh);
_unlock_fh(fh);
return -1;
}
}
/* now rewind the file to the beginning */
if ((filepos = _lseek_lk(fh, 0, SEEK_SET)) == -1) {
_close(fh);
_unlock_fh(fh);
return -1;
}
}
}
/*
* Set FAPPEND flag if appropriate. Don't do this for devices or pipes.
*/
if ( !(fileflags & (FDEV|FPIPE)) && (oflag & _O_APPEND) )
_osfile(fh) |= FAPPEND;
_unlock_fh(fh); /* unlock handle */
return fh; /* return handle */
}
#else /* ndef _WIN32 */
#if defined(_M_MPPC) || defined(_M_M68K)
#include <cruntime.h>
#include <internal.h>
#include <string.h>
#include <memory.h>
#include <msdos.h>
#include <errno.h>
#include <fcntl.h>
#include <macos\files.h>
#include <string.h>
#include <macos\errors.h>
#include <macos\types.h>
#include <io.h>
#include <share.h>
#include <stdlib.h>
#include <sys\types.h>
#include <sys\stat.h>
#include <stdarg.h>
/* define the entry in terminator table */
#pragma data_seg(".CRT$XTX")
const _PVFV pendlowio = _endlowio;
#pragma data_seg()
/* Mac definitions for ioDenyModes */
#define MAC_PERMRD 0x0001
#define MAC_PERMWR 0x0002
#define MAC_DENYRD 0x0010
#define MAC_DENYWR 0x0020
/***
*int _open(path, flag, pmode) - open or create a file
*
*Purpose:
* Opens the file and prepares for subsequent reading or writing.
* the flag argument specifies how to open the file:
* _O_APPEND - reposition file ptr to end before every write
* _O_BINARY - open in binary mode
* _O_CREAT - create a new file* no effect if file already exists
* _O_EXCL - return error if file exists, only use with O_CREAT
* _O_RDONLY - open for reading only
* _O_RDWR - open for reading and writing
* _O_TEXT - open in text mode
* _O_TRUNC - open and truncate to 0 length (must have write permission)
* _O_WRONLY - open for writing only
* exactly one of _O_RDONLY, _O_WRONLY, _O_RDWR must be given
*
* The pmode argument is only required when _O_CREAT is specified. Its
* flag settings:
* _S_IWRITE - writing permitted
* _S_IREAD - reading permitted
* _S_IREAD | _S_IWRITE - both reading and writing permitted
* The current file-permission masks is applied to pmode before
* setting the permission (see umask).
*
* Note, the _creat() function also uses this function but setting up the
* correct arguments and calling _open().
*
*Entry:
* char *path - file name
* int flag - flags for _open()
* int pmode - permission mode for new files
*
*Exit:
* returns file handle of open file if successful
* returns -1 (and sets errno) if fails
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _open (
const char *path,
int oflag,
...
)
{
va_list ap;
va_start(ap, oflag);
/* default sharing mode is DENY NONE */
return _sopen(path, oflag, _SH_DENYNO, va_arg(ap, int));
}
/***
*void __mopen(stpath, fh, ioPermssn, ioDenyModes) - MAC open a file with sharing
*
*Purpose:
* Worker routine to open a file on the MAC. It only opens the file.
* If local open fails it will try AppleShare oepn.
*
*Entry:
* char *stpath - file to open (Pascal string)
* int fh - file handle to use
* int ioPermssn - persmission modes flags
* int ioDenyModes - Deny mode flags
*
*Exit:
* returns TRUE if successful and sets errno & _osfhnd[fh] &
* _osfile[fh] if successful
*
*Exceptions:
*
*******************************************************************************/
int __cdecl __mopen (
char *stpath,
int fh,
int ioPermssn,
int ioDenyModes
)
{
HParamBlockRec parm;
OSErr osErr;
char sz[256];
char buf[10];
char *pch;
//if starts with full path, test the availability of the volume
memcpy(sz, stpath, (*stpath+1));
_p2cstr(sz);
if (*sz != ':' && (pch = strchr(sz, ':')) != NULL)
{
*(pch+1) = '\0';
_c2pstr(sz);
memset(&parm, 0, sizeof(HParamBlockRec));
memset(buf, 0, 10);
parm.ioParam.ioNamePtr = sz;
parm.ioParam.ioBuffer = buf;
parm.ioParam.ioReqCount = 6;
osErr = PBHGetVolParmsSync(&parm);
if (!osErr)
{
if (!(buf[4]&0x8000))
{
parm.ioParam.ioNamePtr = stpath;
parm.ioParam.ioVRefNum = 0;
goto local;
}
}
else
{
_dosmaperr(osErr);
return osErr;
}
}
/* try to open the file using Appleshare calls*/
parm.ioParam.ioNamePtr = stpath;
parm.ioParam.ioVRefNum = 0;
parm.accessParam.ioDenyModes = (unsigned char)ioDenyModes;
_osperm[fh] = (unsigned char)ioDenyModes;
parm.fileParam.ioDirID = 0;
parm.ioParam.ioMisc = NULL;
osErr = PBHOpenDenySync(&parm);
if (osErr == paramErr)
{
local:
/* Try local open */
parm.ioParam.ioPermssn = ioPermssn;
_osperm[fh] = (unsigned char)ioPermssn;
osErr = PBHOpenSync(&parm);
}
if (!osErr)
{
_osfile[fh] |= FOPEN;
_osfhnd[fh] = parm.ioParam.ioRefNum;
}
else
{
_dosmaperr(osErr);
}
return osErr;
}
/***
*int _sopen(path, oflag, shflag, pmode) - open a file with sharing
*
*Purpose:
* Opens the file with possible file sharing.
* shflag defines the sharing flags:
* _SH_DENYRW - deny read and write access to the file
* _SH_DENYNO - permit read and write access
*
* Other flags are the same as _open().
*
* SOPEN is the routine used when file sharing is desired.
*
*Entry:
* char *path - file to open (C string)
* int oflag - open flag
* int shflag - sharing flag
* int pmode - permission mode (needed only when creating file)
*
*Exit:
* returns file handle for the opened file
* returns -1 and sets errno if fails.
*
*Exceptions:
*
*******************************************************************************/
int _cdecl _sopen (
const char *path,
int oflag,
int shflag,
...
)
{
int fh; /* handle of opened file */
OSErr osErr = 0;
unsigned char ioPermssn;
short int ioDenyModes;
ParamBlockRec parm;
int pmode;
va_list ap; /* variable argument (pmode) */
char lpath[256];
if (!*path)
{
errno = ENOENT;
return -1;
}
strcpy(lpath,path);
_c2pstr(lpath);
/* get a file handle*/
for (fh=0; fh <_nfile; fh++)
{
if (!(_osfile[fh] & FOPEN))
{
break;
}
}
if (fh >= _nfile)
{
errno = EMFILE;
_macerrno = 0;
return -1;
}
_osfile[fh] = 0;
/* figure out binary/text mode */
switch (oflag & (_O_BINARY | _O_TEXT))
{
case _O_BINARY:
break;
case _O_TEXT:
_osfile[fh] = (unsigned char)FTEXT;
break;
case _O_TEXT | _O_BINARY:
errno = EINVAL;
return -1;
default:
if (_fmode != _O_BINARY)
{
_osfile[fh] = (unsigned char)FTEXT;
}
break;
}
/* figure out read/write modes */
switch (oflag & (_O_RDWR | _O_RDONLY | _O_WRONLY))
{
case _O_RDONLY:
ioPermssn = fsRdPerm;
_osfile[fh] |= FRDONLY;
if (oflag & _O_TRUNC)
{
errno = EINVAL;
return -1;
}
ioDenyModes = MAC_PERMRD;
break;
case _O_WRONLY:
ioPermssn = fsRdWrShPerm;
_osfile[fh] |= FWRONLY;
ioDenyModes = MAC_PERMWR;
break;
case _O_RDWR:
ioPermssn = fsRdWrPerm;
ioDenyModes = MAC_PERMRD | MAC_PERMWR;
break;
default:
errno = EINVAL;
return -1;
}
switch (shflag)
{
case _SH_DENYRD:
ioDenyModes |= MAC_DENYRD;
break;
case _SH_DENYWR:
ioDenyModes |= MAC_DENYWR;
break;
case _SH_DENYRW:
ioDenyModes |= MAC_DENYRD | MAC_DENYWR;
break;
case _SH_DENYNO:
if (ioPermssn == fsRdWrPerm)
{
ioPermssn = fsRdWrShPerm;
}
break;
default:
errno = EINVAL;
return -1;
}
if (!(oflag & _O_CREAT && oflag & _O_EXCL))
{
/* try to open the file */
if (!__mopen(lpath, fh, ioPermssn, ioDenyModes))
{
oflag &= ~_O_CREAT; /*file open - no need to create*/
}
}
/* Didn't work try creating the file if requested */
if (oflag & _O_CREAT)
{
/* reset errno from mopen, since we can try create*/
errno = 0;
va_start(ap, shflag);
pmode = va_arg(ap, int);
pmode &= ~_umaskval;
if (!(pmode & (_S_IREAD | _S_IWRITE)))
{
errno = EINVAL;
return -1;
}
parm.fileParam.ioNamePtr = lpath;
parm.fileParam.ioVRefNum = 0;
osErr = PBCreateSync(&parm);
if (!osErr)
{
parm.fileParam.ioFDirIndex = 0;
PBGetFInfoSync(&parm);
parm.fileParam.ioFlFndrInfo.fdType = (_osfile[fh] & FTEXT ? 'TEXT' : ' ');
parm.fileParam.ioFlFndrInfo.fdCreator = ' ';
PBSetFInfoSync(&parm);
}
else
{
if (osErr == dupFNErr && oflag & _O_EXCL)
{
errno = EEXIST; /*special case normally returns EACCES*/
_macerrno = osErr;
}
else
{
_dosmaperr(osErr);
}
return -1;
}
if (osErr = __mopen(lpath, fh, ioPermssn, ioDenyModes))
{
_dosmaperr(osErr);
return -1;
}
else if (!(pmode & _S_IWRITE))
{
PBSetFLockSync(&parm);
}
}
if (!(_osfile[fh] & FOPEN))
{
goto ErrExit;
}
parm.ioParam.ioRefNum = _osfhnd[fh];
/* Truncate file */
if (oflag & _O_TRUNC)
{
parm.ioParam.ioMisc = 0;
osErr = PBSetEOFSync(&parm);
if (osErr)
{
_dosmaperr(osErr);
goto ErrExit;
}
}
/* get vol reference */
parm.volumeParam.ioVolIndex = -1;
parm.ioParam.ioNamePtr = lpath;
parm.ioParam.ioVRefNum = 0;
osErr = PBGetVInfoSync(&parm);
if (osErr)
{
_dosmaperr(osErr);
goto ErrExit;
}
_osVRefNum[fh] = parm.volumeParam.ioVRefNum;
if (oflag & _O_APPEND)
{
_osfile[fh] |= FAPPEND;
}
return fh; /* return handle */
ErrExit:
if (_osfile[fh] & FOPEN)
{
PBCloseSync(&parm);
_osfile[fh] = 0;
}
return -1;
}
#endif /* defined(_M_MPPC) || defined(_M_M68K) */
#endif /* _WIN32 */