/***
*getcwd.c - get current working directory
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
*
* contains functions _getcwd, _getdcwd and _getcdrv for getting the
* current working directory. getcwd gets the c.w.d. for the default disk
* drive, whereas _getdcwd allows one to get the c.w.d. for whatever disk
* drive is specified. _getcdrv gets the current drive.
*
*Revision History:
* 09-09-83 RKW created
* 05-??-84 DCW added conditional compilation to handle case of library
* where SS != DS (can't take address of a stack variable).
* 09-??-84 DCW changed comparison of path length to maxlen to take the
* terminating null character into account.
* 11-28-84 DCW changed to return errno values compatibly with the
* System 3 version.
* 05-19-86 SKS adapted for OS/2
* 11-19-86 SKS if pnbuf==NULL, maxlen is ignored;
* eliminated use of intermediate buffer "buf[]"; added
* entry point "_getdcwd()" which takes a drive number.
* 12-03-86 SKS if pnbuf==NULL, maxlen is the minimum allocation size
* 02-05-87 BCM fixed comparison in _getdcwd,
* (unsigned)(len+3) > (int)(maxlen), to handle maxlen < 0,
* since implicit cast to (unsigned) was occurring.
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 12-21-87 WAJ Added _getcdrv()
* 06-22-88 WAJ _getcdrv() is now made for all OS/2 libs
* 10-03-88 JCR 386: Change DOS calls to SYS calls
* 10-04-88 JCR 386: Removed 'far' keyword
* 10-10-88 GJF Made API names match DOSCALLS.H
* 01-31-89 JCR Remove _getcdrv(), which has been renamed _getdrive()
* 04-12-89 JCR Use new OS/2 system calls
* 05-25-89 JCR 386 OS/2 calls use '_syscall' calling convention
* 11-27-89 JCR Corrected ERRNO values
* 12-12-89 JCR Fixed bogus syscall introduced in previous fix (oops)
* 03-07-90 GJF Replaced _LOAD_DS by _CALLTYPE1, added #include
* <cruntime.h>, removed #include <register.h>, removed
* some leftover 16-bit support and fixed the copyright.
* Also, cleaned up the formatting a bit.
* 07-24-90 SBM Compiles cleanly with -W3 (removed unreferenced
* variable), removed redundant includes, removed
* '32' from API names
* 08-10-90 SBM Compiles cleanly with -W3 with new build of compiler
* 09-27-90 GJF New-style function declarator.
* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
* 12-06-90 SRW Added _CRUISER_ and _WIN32 conditionals.
* 01-16-91 GJF ANSI naming.
* 08-21-91 JCR Test DOSQUERYCURRENTDIR call for error return (bug fix)
* 04-23-92 GJF Fixed initialization of DriveVar[].
* 04-28-92 GJF Revised Win32 version.
* 12-09-92 PLM Removed _getdcwd (Mac version only)
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* Change _ValidDrive to _validdrive
* 04-19-93 SKS Move _validdrive to this module
* 04-26-93 SKS Set _doserrno on invalid drive
* 05-26-93 SKS Change _getdcwd to call GetFullPathName() instead of
* reading a current directory environment variable.
* 09-30-93 GJF Removed #include <error.h> (thereby getting rid of a
* bunch of compiler warnings). Also, MTHREAD -> _MT.
* 11-01-93 CFW Enable Unicode variant.
* 12-21-93 CFW Fix API failure error handling.
* 01-04-94 CFW Fix API failure error handling correctly.
* 08-11-94 GJF Revised _validdrive() to use GetDriveType (suggestion
* from Richard Shupak).
* 08-18-94 GJF Revised _validdrive() logic slightly per suggestion
* of Richard Shupak.
* 02-08-95 JWM Spliced _WIN32 & Mac versions.
* 07-01-96 GJF Replaced defined(_WIN32) with !defined(_MAC). Also,
* detab-ed and cleaned up the format a bit.
* 12-17-97 GJF Exception-safe locking.
* 05-17-99 PML Remove all Macintosh support.
*
*******************************************************************************/
#include <cruntime.h>
#include <mtdll.h>
#include <msdos.h>
#include <errno.h>
#include <malloc.h>
#include <oscalls.h>
#include <stdlib.h>
#include <internal.h>
#include <direct.h>
#include <tchar.h>
/***
*_TSCHAR *_getcwd(pnbuf, maxlen) - get current working directory of default drive
*
*Purpose:
* _getcwd gets the current working directory for the user,
* placing it in the buffer pointed to by pnbuf. It returns
* the length of the string put in the buffer. If the length
* of the string exceeds the length of the buffer, maxlen,
* then NULL is returned. If pnbuf = NULL, maxlen is ignored.
* An entry point "_getdcwd()" is defined with takes the above
* parameters, plus a drive number. "_getcwd()" is implemented
* as a call to "_getcwd()" with the default drive (0).
*
* If pnbuf = NULL, maxlen is ignored, and a buffer is automatically
* allocated using malloc() -- a pointer to which is returned by
* _getcwd().
*
* side effects: no global data is used or affected
*
*Entry:
* _TSCHAR *pnbuf = pointer to a buffer maintained by the user;
* int maxlen = length of the buffer pointed to by pnbuf;
*
*Exit:
* Returns pointer to the buffer containing the c.w.d. name
* (same as pnbuf if non-NULL; otherwise, malloc is
* used to allocate a buffer)
*
*Exceptions:
*
*******************************************************************************/
_TSCHAR * __cdecl _tgetcwd (
_TSCHAR *pnbuf,
int maxlen
)
{
_TSCHAR *retval;
#ifdef _MT
_mlock( _ENV_LOCK );
__try {
#endif
#ifdef WPRFLAG
retval = _wgetdcwd_lk(0, pnbuf, maxlen);
#else
retval = _getdcwd_lk(0, pnbuf, maxlen);
#endif
#ifdef _MT
}
__finally {
_munlock( _ENV_LOCK );
}
#endif
return retval;
}
/***
*_TSCHAR *_getdcwd(drive, pnbuf, maxlen) - get c.w.d. for given drive
*
*Purpose:
* _getdcwd gets the current working directory for the user,
* placing it in the buffer pointed to by pnbuf. It returns
* the length of the string put in the buffer. If the length
* of the string exceeds the length of the buffer, maxlen,
* then NULL is returned. If pnbuf = NULL, maxlen is ignored,
* and a buffer is automatically allocated using malloc() --
* a pointer to which is returned by _getdcwd().
*
* side effects: no global data is used or affected
*
*Entry:
* int drive - number of the drive being inquired about
* 0 = default, 1 = 'a:', 2 = 'b:', etc.
* _TSCHAR *pnbuf - pointer to a buffer maintained by the user;
* int maxlen - length of the buffer pointed to by pnbuf;
*
*Exit:
* Returns pointer to the buffer containing the c.w.d. name
* (same as pnbuf if non-NULL; otherwise, malloc is
* used to allocate a buffer)
*
*Exceptions:
*
*******************************************************************************/
#ifdef _MT
_TSCHAR * __cdecl _tgetdcwd (
int drive,
_TSCHAR *pnbuf,
int maxlen
)
{
_TSCHAR *retval;
#ifdef _MT
_mlock( _ENV_LOCK );
__try {
#endif
#ifdef WPRFLAG
retval = _wgetdcwd_lk(drive, pnbuf, maxlen);
#else
retval = _getdcwd_lk(drive, pnbuf, maxlen);
#endif
#ifdef _MT
}
_finally {
_munlock( _ENV_LOCK );
}
#endif
return retval;
}
#ifdef WPRFLAG
wchar_t * __cdecl _wgetdcwd_lk (
#else
char * __cdecl _getdcwd_lk (
#endif
int drive,
_TSCHAR *pnbuf,
int maxlen
)
#else
_TSCHAR * __cdecl _tgetdcwd (
int drive,
_TSCHAR *pnbuf,
int maxlen
)
#endif
{
_TSCHAR *p;
_TSCHAR dirbuf[_MAX_PATH];
_TSCHAR drvstr[4];
int len;
_TSCHAR *pname; /* only used as argument to GetFullPathName */
/*
* GetCurrentDirectory only works for the default drive in Win32
*/
if ( drive != 0 ) {
/*
* Not the default drive - make sure it's valid.
*/
if ( !_validdrive(drive) ) {
_doserrno = ERROR_INVALID_DRIVE;
errno = EACCES;
return NULL;
}
/*
* Get the current directory string on that drive and its length
*/
drvstr[0] = _T('A') - 1 + drive;
drvstr[1] = _T(':');
drvstr[2] = _T('.');
drvstr[3] = _T('\0');
len = GetFullPathName( drvstr,
sizeof(dirbuf) / sizeof(_TSCHAR),
dirbuf,
&pname );
} else {
/*
* Get the current directory string and its length
*/
len = GetCurrentDirectory( sizeof(dirbuf) / sizeof(_TSCHAR),
(LPTSTR)dirbuf );
}
/* API call failed, or buffer not large enough */
if ( len == 0 || ++len > sizeof(dirbuf)/sizeof(_TSCHAR) )
return NULL;
/*
* Set up the buffer.
*/
if ( (p = pnbuf) == NULL ) {
/*
* Allocate a buffer for the user.
*/
if ( (p = (_TSCHAR *)malloc(__max(len, maxlen) * sizeof(_TSCHAR)))
== NULL )
{
errno = ENOMEM;
return NULL;
}
}
else if ( len > maxlen ) {
/*
* Won't fit in the user-supplied buffer!
*/
errno = ERANGE; /* Won't fit in user buffer */
return NULL;
}
/*
* Place the current directory string into the user buffer
*/
return _tcscpy(p, dirbuf);
}
#ifndef WPRFLAG
/***
*int _validdrive( unsigned drive ) -
*
*Purpose: returns non zero if drive is a valid drive number.
*
*Entry: drive = 0 => default drive, 1 => a:, 2 => b: ...
*
*Exit: 0 => drive does not exist.
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _validdrive (
unsigned drive
)
{
unsigned retcode;
char drvstr[4];
if ( drive == 0 )
return 1;
drvstr[0] = 'A' + drive - 1;
drvstr[1] = ':';
drvstr[2] = '\\';
drvstr[3] = '\0';
if ( ((retcode = GetDriveType( drvstr )) == DRIVE_UNKNOWN) ||
(retcode == DRIVE_NO_ROOT_DIR) )
return 0;
return 1;
}
#endif /* WPRFLAG */