/**
* @file
*
* @brief Open a File
* @ingroup libcsupport
*/
/*
* COPYRIGHT (c) 1989-2010.
* On-Line Applications Research Corporation (OAR).
*
* Modifications to support reference counting in the file system are
* Copyright (c) 2012 embedded brains GmbH.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/stat.h>
#include <fcntl.h>
#include <stdarg.h>
#include <unistd.h>
#include <rtems/libio_.h>
static void create_regular_file(
rtems_filesystem_eval_path_context_t *ctx,
mode_t mode
)
{
int rv = 0;
const rtems_filesystem_location_info_t *currentloc =
rtems_filesystem_eval_path_get_currentloc( ctx );
const char *token = rtems_filesystem_eval_path_get_token( ctx );
size_t tokenlen = rtems_filesystem_eval_path_get_tokenlen( ctx );
rv = rtems_filesystem_mknod(
currentloc,
token,
tokenlen,
S_IFREG | mode,
0
);
if ( rv == 0 ) {
/* The mode only applies to future accesses of the newly created file */
rtems_filesystem_eval_path_set_flags( ctx, 0 );
rtems_filesystem_eval_path_set_path( ctx, token, tokenlen );
rtems_filesystem_eval_path_continue( ctx );
} else {
rtems_filesystem_eval_path_error( ctx, 0 );
}
}
static int do_open(
rtems_libio_t *iop,
const char *path,
int oflag,
mode_t mode
)
{
int rv = 0;
int fd = rtems_libio_iop_to_descriptor( iop );
int rwflag = oflag + 1;
bool read_access = (rwflag & _FREAD) == _FREAD;
bool write_access = (rwflag & _FWRITE) == _FWRITE;
bool make = (oflag & O_CREAT) == O_CREAT;
bool exclusive = (oflag & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL);
bool truncate = (oflag & O_TRUNC) == O_TRUNC;
bool open_dir;
#ifdef O_NOFOLLOW
int follow = (oflag & O_NOFOLLOW) == O_NOFOLLOW ? 0 : RTEMS_FS_FOLLOW_LINK;
#else
int follow = RTEMS_FS_FOLLOW_LINK;
#endif
int eval_flags = follow
| (read_access ? RTEMS_FS_PERMS_READ : 0)
| (write_access ? RTEMS_FS_PERMS_WRITE : 0)
| (make ? RTEMS_FS_MAKE : 0)
| (exclusive ? RTEMS_FS_EXCLUSIVE : 0);
rtems_filesystem_eval_path_context_t ctx;
rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
if ( rtems_filesystem_eval_path_has_token( &ctx ) ) {
create_regular_file( &ctx, mode );
}
#ifdef O_DIRECTORY
open_dir = ( oflag & O_DIRECTORY ) == O_DIRECTORY;
#else
open_dir = false;
#endif
if ( write_access || open_dir ) {
const rtems_filesystem_location_info_t *currentloc =
rtems_filesystem_eval_path_get_currentloc( &ctx );
mode_t type = rtems_filesystem_location_type( currentloc );
if ( write_access && S_ISDIR( type ) ) {
rtems_filesystem_eval_path_error( &ctx, EISDIR );
}
if ( open_dir && !S_ISDIR( type ) ) {
rtems_filesystem_eval_path_error( &ctx, ENOTDIR );
}
}
rtems_filesystem_eval_path_extract_currentloc( &ctx, &iop->pathinfo );
rtems_filesystem_eval_path_cleanup( &ctx );
rtems_libio_iop_flags_set( iop, rtems_libio_fcntl_flags( oflag ) );
rv = (*iop->pathinfo.handlers->open_h)( iop, path, oflag, mode );
if ( rv == 0 ) {
rtems_libio_iop_flags_set( iop, LIBIO_FLAGS_OPEN );
if ( truncate ) {
rv = ftruncate( fd, 0 );
if ( rv != 0 ) {
(*iop->pathinfo.handlers->close_h)( iop );
}
}
if ( rv == 0 ) {
rv = fd;
} else {
rv = -1;
}
}
if ( rv < 0 ) {
rtems_libio_free( iop );
}
return rv;
}
/**
* POSIX 1003.1 5.3.1 - Open a File
*/
int open( const char *path, int oflag, ... )
{
int rv = 0;
va_list ap;
mode_t mode = 0;
rtems_libio_t *iop = NULL;
va_start( ap, oflag );
mode = va_arg( ap, mode_t );
iop = rtems_libio_allocate();
if ( iop != NULL ) {
rv = do_open( iop, path, oflag, mode );
} else {
errno = ENFILE;
rv = -1;
}
va_end( ap );
return rv;
}
#if defined(RTEMS_NEWLIB) && !defined(HAVE__OPEN_R)
#include <reent.h>
/**
* This is the Newlib dependent reentrant version of open().
*/
int _open_r(
struct _reent *ptr RTEMS_UNUSED,
const char *buf,
int oflag,
int mode
)
{
return open( buf, oflag, mode );
}
#endif