win32: add qemu_close_socket_osfhandle()

Close the given file descriptor, but returns the underlying SOCKET.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230320133643.1618437-2-marcandre.lureau@redhat.com>
This commit is contained in:
Marc-André Lureau 2023-03-20 17:36:41 +04:00
parent aa9e7fa468
commit f3ab43accf
2 changed files with 53 additions and 37 deletions

View File

@ -171,10 +171,21 @@ bool qemu_socket_select(int sockfd, WSAEVENT hEventObject,
bool qemu_socket_unselect(int sockfd, Error **errp);
/* We wrap all the sockets functions so that we can
* set errno based on WSAGetLastError()
/* We wrap all the sockets functions so that we can set errno based on
* WSAGetLastError(), and use file-descriptors instead of SOCKET.
*/
/*
* qemu_close_socket_osfhandle:
* @fd: a file descriptor associated with a SOCKET
*
* Close only the C run-time file descriptor, leave the SOCKET opened.
*
* Returns zero on success. On error, -1 is returned, and errno is set to
* indicate the error.
*/
int qemu_close_socket_osfhandle(int fd);
#undef close
#define close qemu_close_wrap
int qemu_close_wrap(int fd);

View File

@ -479,40 +479,27 @@ int qemu_bind_wrap(int sockfd, const struct sockaddr *addr,
return ret;
}
#undef close
int qemu_close_wrap(int fd)
int qemu_close_socket_osfhandle(int fd)
{
int ret;
SOCKET s = _get_osfhandle(fd);
DWORD flags = 0;
SOCKET s = INVALID_SOCKET;
if (fd_is_socket(fd)) {
s = _get_osfhandle(fd);
/*
* If we were to just call _close on the descriptor, it would close the
* HANDLE, but it wouldn't free any of the resources associated to the
* SOCKET, and we can't call _close after calling closesocket, because
* closesocket has already closed the HANDLE, and _close would attempt to
* close the HANDLE again, resulting in a double free. We can however
* protect the HANDLE from actually being closed long enough to close the
* file descriptor, then close the socket itself.
*/
if (!GetHandleInformation((HANDLE)s, &flags)) {
errno = EACCES;
return -1;
}
if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_PROTECT_FROM_CLOSE, HANDLE_FLAG_PROTECT_FROM_CLOSE)) {
errno = EACCES;
return -1;
}
/*
* If we were to just call _close on the descriptor, it would close the
* HANDLE, but it wouldn't free any of the resources associated to the
* SOCKET, and we can't call _close after calling closesocket, because
* closesocket has already closed the HANDLE, and _close would attempt to
* close the HANDLE again, resulting in a double free. We can however
* protect the HANDLE from actually being closed long enough to close the
* file descriptor, then close the socket itself.
*/
if (!GetHandleInformation((HANDLE)s, &flags)) {
errno = EACCES;
return -1;
}
ret = close(fd);
if (s != INVALID_SOCKET && !SetHandleInformation((HANDLE)s, flags, flags)) {
if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_PROTECT_FROM_CLOSE, HANDLE_FLAG_PROTECT_FROM_CLOSE)) {
errno = EACCES;
return -1;
}
@ -521,15 +508,33 @@ int qemu_close_wrap(int fd)
* close() returns EBADF since we PROTECT_FROM_CLOSE the underlying handle,
* but the FD is actually freed
*/
if (ret < 0 && (s == INVALID_SOCKET || errno != EBADF)) {
return ret;
if (close(fd) < 0 && errno != EBADF) {
return -1;
}
if (s != INVALID_SOCKET) {
ret = closesocket(s);
if (ret < 0) {
errno = socket_error();
}
if (!SetHandleInformation((HANDLE)s, flags, flags)) {
errno = EACCES;
return -1;
}
return 0;
}
int qemu_close_wrap(int fd)
{
SOCKET s = INVALID_SOCKET;
int ret = -1;
if (!fd_is_socket(fd)) {
return close(fd);
}
s = _get_osfhandle(fd);
qemu_close_socket_osfhandle(fd);
ret = closesocket(s);
if (ret < 0) {
errno = socket_error();
}
return ret;