227 lines
8 KiB
C
227 lines
8 KiB
C
|
/***
|
||
|
|
*_filbuf.c - fill buffer and get character
|
||
|
|
*
|
||
|
|
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* defines _filbuf() - fill buffer and read first character, allocate
|
||
|
|
* buffer if there is none. Used from getc().
|
||
|
|
* defines _filwbuf() - fill buffer and read first wide character, allocate
|
||
|
|
* buffer if there is none. Used from getwc().
|
||
|
|
*
|
||
|
|
*Revision History:
|
||
|
|
* 09-01-83 RN initial version
|
||
|
|
* 06-26-85 TC added code to handle variable length buffers
|
||
|
|
* 04-16-87 JCR added _IOUNGETC support
|
||
|
|
* 08-04-87 JCR added _getbuff routine
|
||
|
|
* 09-28-87 JCR Corrected _iob2 indexing (now uses _iob_index() macro).
|
||
|
|
* 11-06-87 JCR Multi-thread support; also, split _getbuf() off
|
||
|
|
* 12-11-87 JCR Added "_LOAD_DS" to declaration
|
||
|
|
* 01-11-88 JCR Merged mthread version into normal code
|
||
|
|
* 01-13-88 SKS Changed bogus "_fileno_lk" to "fileno"
|
||
|
|
* 03-04-88 JCR Read() return value must be considered unsigned, not
|
||
|
|
* signed
|
||
|
|
* 06-06-88 JCR Optimized _iob2 references
|
||
|
|
* 06-13-88 JCR Use near pointer to reference _iob[] entries
|
||
|
|
* 08-25-88 GJF Don't use FP_OFF() macro for the 386
|
||
|
|
* 06-20-89 PHG Re-activate C version, propogated fixes
|
||
|
|
* 08-28-89 JCR Removed _NEAR_ for 386
|
||
|
|
* 02-15-90 GJF _iob[], _iob2[] merge. Also, fixed copyright and
|
||
|
|
* alignment.
|
||
|
|
* 03-16-90 GJF Replaced cdecl _LOAD_DS with _CALLTYPE1, added #include
|
||
|
|
* <cruntime.h> and removed #include <register.h>. Also,
|
||
|
|
* removed some leftover 16-bit support.
|
||
|
|
* 03-27-90 GJF Added #include <io.h>.
|
||
|
|
* 07-23-90 SBM Replaced <assertm.h> by <assert.h>
|
||
|
|
* 10-03-90 GJF New-style function declarator.
|
||
|
|
* 01-22-91 GJF ANSI naming.
|
||
|
|
* 03-27-92 DJM POSIX support.
|
||
|
|
* 08-26-92 GJF Include unistd.h for POSIX build.
|
||
|
|
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
|
||
|
|
* 04-26-93 CFW Wide char enable.
|
||
|
|
* 05-06-93 CFW Optimize wide char conversion.
|
||
|
|
* 05-24-93 GJF Detect small buffer size (_SMALL_BUFSIZ) resulting
|
||
|
|
* from fseek call on read-access-only stream and
|
||
|
|
* restore the larger size (_INTERNAL_BUFSIZ) for the
|
||
|
|
* next _filbuf call.
|
||
|
|
* 06-22-93 GJF Check _IOSETVBUF (new) before changing buffer size.
|
||
|
|
* 11-05-93 GJF Merged with NT SDK version (picked up _NTSUBSET_
|
||
|
|
* stuff).
|
||
|
|
* 10-17-94 BWT Move wchar.h to non-POSIX build (ino_t definitions conflict)
|
||
|
|
* 02-06-94 CFW assert -> _ASSERTE.
|
||
|
|
* 02-16-95 GJF Appended Mac version of source file (somewhat cleaned
|
||
|
|
* up), with appropriate #ifdef-s.
|
||
|
|
* 06-12-95 GJF Replaced _osfile[] with _osfile() (macro referencing
|
||
|
|
* field in ioinfo struct).
|
||
|
|
* 07-27-95 GJF Replaced _osfile() with _osfile_safe().
|
||
|
|
* 12-07-95 SKS Fix misspelling of _NTSUBSET_ (final _ was missing)
|
||
|
|
* 05-17-99 PML Remove all Macintosh support.
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
#include <cruntime.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <file2.h>
|
||
|
|
#include <io.h>
|
||
|
|
#include <dbgint.h>
|
||
|
|
#include <malloc.h>
|
||
|
|
#include <internal.h>
|
||
|
|
#ifdef _POSIX_
|
||
|
|
#include <unistd.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#else
|
||
|
|
#include <msdos.h>
|
||
|
|
#include <wchar.h>
|
||
|
|
#endif
|
||
|
|
#ifdef _MT
|
||
|
|
#include <mtdll.h>
|
||
|
|
#endif
|
||
|
|
#include <tchar.h>
|
||
|
|
|
||
|
|
#ifndef _UNICODE
|
||
|
|
|
||
|
|
/***
|
||
|
|
*int _filbuf(stream) - fill buffer and get first character
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* get a buffer if the file doesn't have one, read into it, return first
|
||
|
|
* char. try to get a buffer, if a user buffer is not assigned. called
|
||
|
|
* only from getc; intended for use only within library. assume no input
|
||
|
|
* stream is to remain unbuffered when memory is available unless it is
|
||
|
|
* marked _IONBF. at worst, give it a single char buffer. the need for a
|
||
|
|
* buffer, no matter how small, becomes evident when we consider the
|
||
|
|
* ungetc's necessary in scanf
|
||
|
|
*
|
||
|
|
* [NOTE: Multi-thread - _filbuf() assumes that the caller has aquired
|
||
|
|
* the stream lock, if needed.]
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* FILE *stream - stream to read from
|
||
|
|
*
|
||
|
|
*Exit:
|
||
|
|
* returns first character from buffer (next character to be read)
|
||
|
|
* returns EOF if the FILE is actually a string, or not open for reading,
|
||
|
|
* or if open for writing or if no more chars to read.
|
||
|
|
* all fields in FILE structure may be changed except _file.
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
int __cdecl _filbuf (
|
||
|
|
FILE *str
|
||
|
|
)
|
||
|
|
|
||
|
|
#else /* _UNICODE */
|
||
|
|
|
||
|
|
/***
|
||
|
|
*int _filwbuf(stream) - fill buffer and get first wide character
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* get a buffer if the file doesn't have one, read into it, return first
|
||
|
|
* char. try to get a buffer, if a user buffer is not assigned. called
|
||
|
|
* only from getc; intended for use only within library. assume no input
|
||
|
|
* stream is to remain unbuffered when memory is available unless it is
|
||
|
|
* marked _IONBF. at worst, give it a single char buffer. the need for a
|
||
|
|
* buffer, no matter how small, becomes evident when we consider the
|
||
|
|
* ungetc's necessary in scanf
|
||
|
|
*
|
||
|
|
* [NOTE: Multi-thread - _filwbuf() assumes that the caller has aquired
|
||
|
|
* the stream lock, if needed.]
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* FILE *stream - stream to read from
|
||
|
|
*
|
||
|
|
*Exit:
|
||
|
|
* returns first wide character from buffer (next character to be read)
|
||
|
|
* returns WEOF if the FILE is actually a string, or not open for reading,
|
||
|
|
* or if open for writing or if no more chars to read.
|
||
|
|
* all fields in FILE structure may be changed except _file.
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
int __cdecl _filwbuf (
|
||
|
|
FILE *str
|
||
|
|
)
|
||
|
|
|
||
|
|
#endif /* _UNICODE */
|
||
|
|
|
||
|
|
{
|
||
|
|
#ifdef _NTSUBSET_
|
||
|
|
|
||
|
|
return(_TEOF);
|
||
|
|
|
||
|
|
#else /* ndef _NTSUBSET_ */
|
||
|
|
|
||
|
|
REG1 FILE *stream;
|
||
|
|
|
||
|
|
_ASSERTE(str != NULL);
|
||
|
|
|
||
|
|
/* Init pointer to _iob2 entry. */
|
||
|
|
stream = str;
|
||
|
|
|
||
|
|
if (!inuse(stream) || stream->_flag & _IOSTRG)
|
||
|
|
return(_TEOF);
|
||
|
|
|
||
|
|
if (stream->_flag & _IOWRT) {
|
||
|
|
#ifdef _POSIX_
|
||
|
|
errno = EBADF;
|
||
|
|
#endif
|
||
|
|
stream->_flag |= _IOERR;
|
||
|
|
return(_TEOF);
|
||
|
|
}
|
||
|
|
|
||
|
|
stream->_flag |= _IOREAD;
|
||
|
|
|
||
|
|
/* Get a buffer, if necessary. */
|
||
|
|
|
||
|
|
if (!anybuf(stream))
|
||
|
|
_getbuf(stream);
|
||
|
|
else
|
||
|
|
stream->_ptr = stream->_base;
|
||
|
|
|
||
|
|
#ifdef _POSIX_
|
||
|
|
stream->_cnt = read(fileno(stream), stream->_base, stream->_bufsiz);
|
||
|
|
#else
|
||
|
|
stream->_cnt = _read(_fileno(stream), stream->_base, stream->_bufsiz);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef _UNICODE
|
||
|
|
if ((stream->_cnt == 0) || (stream->_cnt == -1)) {
|
||
|
|
#else /* _UNICODE */
|
||
|
|
if ((stream->_cnt == 0) || (stream->_cnt == 1) || stream->_cnt == -1) {
|
||
|
|
#endif /* _UNICODE */
|
||
|
|
stream->_flag |= stream->_cnt ? _IOERR : _IOEOF;
|
||
|
|
stream->_cnt = 0;
|
||
|
|
return(_TEOF);
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifndef _POSIX_
|
||
|
|
if ( !(stream->_flag & (_IOWRT|_IORW)) &&
|
||
|
|
((_osfile_safe(_fileno(stream)) & (FTEXT|FEOFLAG)) ==
|
||
|
|
(FTEXT|FEOFLAG)) )
|
||
|
|
stream->_flag |= _IOCTRLZ;
|
||
|
|
#endif
|
||
|
|
/* Check for small _bufsiz (_SMALL_BUFSIZ). If it is small and
|
||
|
|
if it is our buffer, then this must be the first _filbuf after
|
||
|
|
an fseek on a read-access-only stream. Restore _bufsiz to its
|
||
|
|
larger value (_INTERNAL_BUFSIZ) so that the next _filbuf call,
|
||
|
|
if one is made, will fill the whole buffer. */
|
||
|
|
if ( (stream->_bufsiz == _SMALL_BUFSIZ) && (stream->_flag &
|
||
|
|
_IOMYBUF) && !(stream->_flag & _IOSETVBUF) )
|
||
|
|
{
|
||
|
|
stream->_bufsiz = _INTERNAL_BUFSIZ;
|
||
|
|
}
|
||
|
|
#ifndef _UNICODE
|
||
|
|
stream->_cnt--;
|
||
|
|
return(0xff & *stream->_ptr++);
|
||
|
|
#else /* _UNICODE */
|
||
|
|
stream->_cnt -= sizeof(wchar_t);
|
||
|
|
return (0xffff & *((wchar_t *)(stream->_ptr))++);
|
||
|
|
#endif /* _UNICODE */
|
||
|
|
|
||
|
|
#endif /* _NTSUBSET_ */
|
||
|
|
}
|