/* * freopen.c - open a file and associate a stream with it *//* $Header: /cvsup/minix/src/lib/stdio/freopen.c,v 1.3 2005/09/05 17:17:58 beng Exp $ */#if	defined(_POSIX_SOURCE)#include	<sys/types.h>#endif#include	<stdio.h>#include	<stdlib.h>#include	"loc_incl.h"#include	<sys/stat.h>#define	PMODE		0666/* Do not "optimize" this file to use the open with O_CREAT if the file * does not exist. The reason is given in fopen.c. */#define	O_RDONLY	0#define	O_WRONLY	1#define	O_RDWR		2#define	O_CREAT		0x010#define	O_TRUNC		0x020#define	O_APPEND	0x040int _open(const char *path, int flags);int _creat(const char *path, _mnx_Mode_t mode);int _close(int d);FILE *freopen(const char *name, const char *mode, FILE *stream){	register int i;	struct stat st;	int rwmode = 0, rwflags = 0;	int fd, flags = stream->_flags & (_IONBF | _IOFBF | _IOLBF | _IOMYBUF);	(void) fflush(stream);				/* ignore errors */	(void) _close(fileno(stream));	switch(*mode++) {	case 'r':		flags |= _IOREAD;			rwmode = O_RDONLY;		break;	case 'w':		flags |= _IOWRITE;		rwmode = O_WRONLY;		rwflags = O_CREAT | O_TRUNC;		break;	case 'a': 		flags |= _IOWRITE | _IOAPPEND;		rwmode = O_WRONLY;		rwflags |= O_APPEND | O_CREAT;		break;         	default:		goto loser;	}	while (*mode) {		switch(*mode++) {		case 'b':			continue;		case '+':			rwmode = O_RDWR;			flags |= _IOREAD | _IOWRITE;			continue;		/* The sequence may be followed by aditional characters */		default:			break;		}		break;	}	if ((rwflags & O_TRUNC)	    || (((fd = _open(name, rwmode)) < 0)		    && (rwflags & O_CREAT))) {		if (((fd = _creat(name, PMODE)) < 0) && flags | _IOREAD) {			(void) _close(fd);			fd = _open(name, rwmode);		}	}	if (fd < 0) {		goto loser;	}	if ( fstat( fd, &st ) == 0 ) {		if ( st.st_mode & S_IFIFO ) flags |= _IOFIFO;	} else {		goto loser;	}		stream->_count = 0;	stream->_fd = fd;	stream->_flags = flags;	return stream;loser:	for( i = 0; i < FOPEN_MAX; i++) {		if (stream == __iotab[i]) {			__iotab[i] = 0;			break;		}	}	if (stream != stdin && stream != stdout && stream != stderr)		free((void *)stream);	return (FILE *)NULL;	}