gambas-source-code/main/gbx/gbx_stream_direct.c
Benoît Minisini a3c4a852e3 [INTERPRETER]
* NEW: When opening an existing file descriptor, check that it is opened 
  with a compatible mode. Otherwise raise an "Access forbidden" error.


git-svn-id: svn://localhost/gambas/trunk@4133 867c0c6c-44f3-4631-809d-bfa615b0a4ec
2011-09-18 15:36:30 +00:00

190 lines
3.5 KiB
C

/***************************************************************************
gbx_stream_direct.c
(c) 2000-2011 Benoît Minisini <gambas@users.sourceforge.net>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
MA 02110-1301, USA.
***************************************************************************/
#define __STREAM_IMPL_C
#include "gb_common.h"
#include "gb_error.h"
#include "gbx_value.h"
#include "gb_limit.h"
#include "gbx_number.h"
#include <fcntl.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#include "gbx_stream.h"
#define FD (stream->direct.fd)
static int stream_open(STREAM *stream, const char *path, int mode)
{
int fd;
struct stat info;
int fmode;
VALUE val;
if (mode & ST_CREATE)
fmode = O_CREAT | O_TRUNC;
else if (mode & ST_APPEND)
fmode = O_APPEND | O_CREAT;
else
fmode = 0;
switch (mode & ST_MODE)
{
case ST_READ: fmode |= O_RDONLY; break;
case ST_WRITE: fmode |= O_WRONLY; break;
case ST_READ_WRITE: fmode |= O_RDWR; break;
default: fmode |= O_RDONLY;
}
if (path[0] == '.' && isdigit(path[1]))
{
if ((mode & ST_CREATE) || (mode & ST_APPEND))
THROW(E_ACCESS);
if (NUMBER_from_string(NB_READ_INTEGER, &path[1], strlen(path) - 1, &val) || val._integer.value < 0)
{
errno = ENOENT;
return TRUE;
}
fd = val._integer.value;
if ((fcntl(fd, F_GETFL, NULL) & O_RDWR) != (fmode & O_RDWR))
THROW(E_ACCESS);
stream->direct.watch = TRUE;
}
else
{
stream->direct.watch = FALSE;
fd = open(path, fmode, 0666);
if (fd < 0)
return TRUE;
if (fstat(fd, &info) < 0)
return TRUE;
if (S_ISDIR(info.st_mode))
{
errno = EISDIR;
return TRUE;
}
if (!S_ISREG(info.st_mode))
{
stream->common.available_now = FALSE;
fcntl(fd, F_SETFL, O_NONBLOCK);
}
else
stream->common.available_now = TRUE;
}
FD = fd;
return FALSE;
}
static int stream_close(STREAM *stream)
{
if (!stream->direct.watch)
{
if (close(FD) < 0)
return TRUE;
}
FD = -1;
return FALSE;
}
static int stream_read(STREAM *stream, char *buffer, int len)
{
return STREAM_read_direct(FD, buffer, len);
}
static int stream_getchar(STREAM *stream, char *buffer)
{
return read(FD, buffer, 1) <= 0;
}
static int stream_write(STREAM *stream, char *buffer, int len)
{
return STREAM_write_direct(FD, buffer, len);
}
static int stream_seek(STREAM *stream, int64_t pos, int whence)
{
return (lseek(FD, pos, whence) < 0);
}
static int stream_tell(STREAM *stream, int64_t *pos)
{
*pos = lseek(FD, 0, SEEK_CUR);
return (*pos < 0);
}
static int stream_flush(STREAM *stream)
{
return FALSE;
}
#define stream_eof NULL
static int stream_lof(STREAM *stream, int64_t *len)
{
struct stat info;
if (!stream->common.available_now)
return TRUE;
if (fstat(FD, &info) < 0)
return TRUE;
*len = info.st_size;
return FALSE;
}
static int stream_handle(STREAM *stream)
{
return FD;
}
DECLARE_STREAM(STREAM_direct);