reactos/reactos/lib/crtdll/stdio/fopen.c
Boudewijn Dekker d21b624ded no message
svn path=/trunk/; revision=509
1999-05-24 14:47:21 +00:00

77 lines
1.5 KiB
C

/* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */
#include <crtdll/sys/types.h>
#include <crtdll/stdio.h>
#include <crtdll/io.h>
#include <crtdll/fcntl.h>
#include <crtdll/internal/file.h>
//might change fopen(file,mode) -> fsopen(file,mode,_SH_DENYNO);
FILE * __alloc_file(void);
FILE* fopen(const char *file, const char *mode)
{
FILE *f;
int fd, rw, oflags = 0;
char tbchar;
if (file == 0)
return 0;
if (mode == 0)
return 0;
f = __alloc_file();
if (f == NULL)
return NULL;
rw = (mode[1] == '+') || (mode[1] && (mode[2] == '+'));
switch (*mode)
{
case 'a':
oflags = O_CREAT | (rw ? O_RDWR : O_WRONLY);
break;
case 'r':
oflags = rw ? O_RDWR : O_RDONLY;
break;
case 'w':
oflags = O_TRUNC | O_CREAT | (rw ? O_RDWR : O_WRONLY);
break;
default:
return (NULL);
}
if (mode[1] == '+')
tbchar = mode[2];
else
tbchar = mode[1];
if (tbchar == 't')
oflags |= O_TEXT;
else if (tbchar == 'b')
oflags |= O_BINARY;
else
oflags |= (_fmode & (O_TEXT|O_BINARY));
fd = _open(file, oflags, 0);
if (fd < 0)
return NULL;
// ms crtdll ensures that writes will end up at the end of file in append mode
// we just move the file pointer to the end of file initially
if (*mode == 'a')
lseek(fd, 0, SEEK_END);
f->_cnt = 0;
f->_file = fd;
f->_bufsiz = 0;
if (rw)
f->_flag = _IOREAD | _IOWRT;
else if (*mode == 'r')
f->_flag = _IOREAD;
else
f->_flag = _IOWRT;
f->_base = f->_ptr = NULL;
return f;
}