newlib/winsup/cygwin/fhandler_virtual.cc

237 lines
4.3 KiB
C++

/* fhandler_virtual.cc: base fhandler class for virtual filesystems
Copyright 2002 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <unistd.h>
#include <stdlib.h>
#include <sys/cygwin.h>
#include "cygerrno.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "shared_info.h"
#include "cygheap.h"
#include <assert.h>
#include <dirent.h>
fhandler_virtual::fhandler_virtual ():
fhandler_base (), filebuf (NULL), bufalloc ((size_t) -1),
fileid (-1)
{
}
fhandler_virtual::~fhandler_virtual ()
{
if (filebuf)
free (filebuf);
filebuf = NULL;
}
void
fhandler_virtual::fixup_after_exec (HANDLE)
{
if (filebuf)
filebuf = NULL;
}
DIR *
fhandler_virtual::opendir ()
{
DIR *dir;
DIR *res = NULL;
size_t len;
if (exists () <= 0)
set_errno (ENOTDIR);
else if ((len = strlen (get_name ())) > MAX_PATH - 3)
set_errno (ENAMETOOLONG);
else if ((dir = (DIR *) malloc (sizeof (DIR))) == NULL)
set_errno (ENOMEM);
else if ((dir->__d_dirname = (char *) malloc (len + 3)) == NULL)
{
free (dir);
set_errno (ENOMEM);
}
else if ((dir->__d_dirent =
(struct dirent *) malloc (sizeof (struct dirent))) == NULL)
{
free (dir);
set_errno (ENOMEM);
}
else
{
strcpy (dir->__d_dirname, get_name ());
dir->__d_dirent->d_version = __DIRENT_VERSION;
cygheap_fdnew fd;
if (fd >= 0)
{
fd = this;
fd->set_nohandle (true);
dir->__d_dirent->d_fd = fd;
dir->__fh = this;
dir->__d_cookie = __DIRENT_COOKIE;
dir->__handle = INVALID_HANDLE_VALUE;
dir->__d_position = 0;
dir->__d_dirhash = get_namehash ();
res = dir;
}
}
syscall_printf ("%p = opendir (%s)", res, get_name ());
return res;
}
_off64_t fhandler_virtual::telldir (DIR * dir)
{
return dir->__d_position;
}
void
fhandler_virtual::seekdir (DIR * dir, _off64_t loc)
{
dir->__d_position = loc;
return;
}
void
fhandler_virtual::rewinddir (DIR * dir)
{
dir->__d_position = 0;
return;
}
int
fhandler_virtual::closedir (DIR * dir)
{
return 0;
}
_off64_t
fhandler_virtual::lseek (_off64_t offset, int whence)
{
/*
* On Linux, when you lseek within a /proc file,
* the contents of the file are updated.
*/
if (!fill_filebuf ())
return (_off64_t) -1;
switch (whence)
{
case SEEK_SET:
position = offset;
break;
case SEEK_CUR:
position += offset;
break;
case SEEK_END:
position = filesize + offset;
break;
default:
set_errno (EINVAL);
return (_off64_t) -1;
}
return position;
}
int
fhandler_virtual::dup (fhandler_base * child)
{
int ret = fhandler_base::dup (child);
if (!ret)
{
fhandler_virtual *fhproc_child = (fhandler_virtual *) child;
fhproc_child->filebuf = (char *) malloc (filesize);
fhproc_child->bufalloc = fhproc_child->filesize = filesize;
fhproc_child->position = position;
memcpy (fhproc_child->filebuf, filebuf, filesize);
fhproc_child->set_flags (get_flags ());
}
return ret;
}
int
fhandler_virtual::close ()
{
if (filebuf)
free (filebuf);
filebuf = NULL;
bufalloc = (size_t) -1;
user_shared->delqueue.process_queue ();
return 0;
}
void
fhandler_virtual::read (void *ptr, size_t& len)
{
if (len == 0)
return;
if (openflags & O_DIROPEN)
{
set_errno (EISDIR);
len = (size_t) -1;
return;
}
if (!filebuf)
{
len = (size_t) 0;
return;
}
if ((ssize_t) len > filesize - position)
len = (size_t) (filesize - position);
if ((ssize_t) len < 0)
len = 0;
else
memcpy (ptr, filebuf + position, len);
position += len;
}
int
fhandler_virtual::write (const void *ptr, size_t len)
{
set_errno (EACCES);
return -1;
}
/* low-level open for all proc files */
int
fhandler_virtual::open (int flags, mode_t mode)
{
set_r_binary (1);
set_w_binary (1);
set_has_acls (false);
set_isremote (false);
/* what to do about symlinks? */
set_symlink_p (false);
set_execable_p (not_executable);
set_socket_p (false);
set_flags ((flags & ~O_TEXT) | O_BINARY);
return 1;
}
int
fhandler_virtual::exists ()
{
return 0;
}
bool
fhandler_virtual::fill_filebuf ()
{
return true;
}