ocaml/otherlibs/win32unix/channels.c

142 lines
4.5 KiB
C

/**************************************************************************/
/* */
/* OCaml */
/* */
/* Xavier Leroy, projet Cristal, INRIA Rocquencourt */
/* */
/* Copyright 1996 Institut National de Recherche en Informatique et */
/* en Automatique. */
/* */
/* All rights reserved. This file is distributed under the terms of */
/* the GNU Lesser General Public License version 2.1, with the */
/* special exception on linking described in the file LICENSE. */
/* */
/**************************************************************************/
#define CAML_INTERNALS
#include <caml/mlvalues.h>
#include <caml/alloc.h>
#include <caml/io.h>
#include <caml/memory.h>
#include "unixsupport.h"
#include <fcntl.h>
#include <io.h>
/* Check that the given file descriptor has "stream semantics" and
can therefore be used as part of buffered I/O. Things that
don't have "stream semantics" include block devices and
UDP (datagram) sockets.
Returns 0 if OK, a Win32 error code if error. */
static DWORD win_check_stream_semantics(value handle)
{
switch (Descr_kind_val(handle)) {
case KIND_HANDLE:
switch (GetFileType(Handle_val(handle)) & ~FILE_TYPE_REMOTE) {
case FILE_TYPE_DISK: case FILE_TYPE_CHAR: case FILE_TYPE_PIPE:
return 0;
default: {
DWORD err = GetLastError();
return err == NO_ERROR ? ERROR_INVALID_ACCESS : err;
}
}
case KIND_SOCKET: {
int so_type;
int so_type_len = sizeof(so_type);
if (getsockopt(Socket_val(handle), SOL_SOCKET, SO_TYPE,
(void *) &so_type, &so_type_len) != 0)
return WSAGetLastError();
switch (so_type) {
case SOCK_STREAM:
return 0;
default:
return ERROR_INVALID_ACCESS;
}
}
default:
return ERROR_INVALID_ACCESS;
}
}
int win_CRT_fd_of_filedescr(value handle)
{
if (CRT_fd_val(handle) != NO_CRT_FD) {
return CRT_fd_val(handle);
} else {
int fd = _open_osfhandle((intptr_t) Handle_val(handle), O_BINARY);
if (fd == -1) uerror("channel_of_descr", Nothing);
CRT_fd_val(handle) = fd;
return fd;
}
}
CAMLprim value win_inchannel_of_filedescr(value handle)
{
CAMLparam1(handle);
CAMLlocal1(vchan);
struct channel * chan;
DWORD err;
#if defined(_MSC_VER) && _MSC_VER < 1400
fflush(stdin);
#endif
err = win_check_stream_semantics(handle);
if (err != 0) { win32_maperr(err); uerror("in_channel_of_descr", Nothing); }
chan = caml_open_descriptor_in(win_CRT_fd_of_filedescr(handle));
chan->flags |= CHANNEL_FLAG_MANAGED_BY_GC;
/* as in caml_ml_open_descriptor_in() */
if (Descr_kind_val(handle) == KIND_SOCKET)
chan->flags |= CHANNEL_FLAG_FROM_SOCKET;
vchan = caml_alloc_channel(chan);
CAMLreturn(vchan);
}
CAMLprim value win_outchannel_of_filedescr(value handle)
{
CAMLparam1(handle);
CAMLlocal1(vchan);
int fd;
struct channel * chan;
DWORD err;
err = win_check_stream_semantics(handle);
if (err != 0) { win32_maperr(err); uerror("out_channel_of_descr", Nothing); }
chan = caml_open_descriptor_out(win_CRT_fd_of_filedescr(handle));
chan->flags |= CHANNEL_FLAG_MANAGED_BY_GC;
/* as in caml_ml_open_descriptor_out() */
if (Descr_kind_val(handle) == KIND_SOCKET)
chan->flags |= CHANNEL_FLAG_FROM_SOCKET;
vchan = caml_alloc_channel(chan);
CAMLreturn(vchan);
}
CAMLprim value win_filedescr_of_channel(value vchan)
{
CAMLparam1(vchan);
CAMLlocal1(fd);
struct channel * chan;
HANDLE h;
chan = Channel(vchan);
if (chan->fd == -1) uerror("descr_of_channel", Nothing);
h = (HANDLE) _get_osfhandle(chan->fd);
if (chan->flags & CHANNEL_FLAG_FROM_SOCKET)
fd = win_alloc_socket((SOCKET) h);
else
fd = win_alloc_handle(h);
CRT_fd_val(fd) = chan->fd;
CAMLreturn(fd);
}
CAMLprim value win_handle_fd(value vfd)
{
int crt_fd = Int_val(vfd);
/* PR#4750: do not use the _or_socket variant as it can cause performance
degradation and this function is only used with the standard
handles 0, 1, 2, which are not sockets. */
value res = win_alloc_handle((HANDLE) _get_osfhandle(crt_fd));
CRT_fd_val(res) = crt_fd;
return res;
}