diff options
Diffstat (limited to 'lib/sockets.c')
| -rw-r--r-- | lib/sockets.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/lib/sockets.c b/lib/sockets.c new file mode 100644 index 0000000..eec1ec8 --- /dev/null +++ b/lib/sockets.c @@ -0,0 +1,161 @@ +/* sockets.c --- wrappers for Windows socket functions + + Copyright (C) 2008-2018 Free Software Foundation, Inc. + + 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 3 of the License, 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, see <https://www.gnu.org/licenses/>. */ + +/* Written by Simon Josefsson */ + +#include <config.h> + +/* Specification. */ +#include "sockets.h" + +#if WINDOWS_SOCKETS + +/* This includes winsock2.h on MinGW. */ +# include <sys/socket.h> + +# include "fd-hook.h" +# if GNULIB_MSVC_NOTHROW +# include "msvc-nothrow.h" +# else +# include <io.h> +# endif + +/* Get set_winsock_errno, FD_TO_SOCKET etc. */ +# include "w32sock.h" + +static int +close_fd_maybe_socket (const struct fd_hook *remaining_list, + gl_close_fn primary, + int fd) +{ + /* Note about multithread-safety: There is a race condition where, between + our calls to closesocket() and the primary close(), some other thread + could make system calls that allocate precisely the same HANDLE value + as sock; then the primary close() would call CloseHandle() on it. */ + SOCKET sock; + WSANETWORKEVENTS ev; + + /* Test whether fd refers to a socket. */ + sock = FD_TO_SOCKET (fd); + ev.lNetworkEvents = 0xDEADBEEF; + WSAEnumNetworkEvents (sock, NULL, &ev); + if (ev.lNetworkEvents != 0xDEADBEEF) + { + /* fd refers to a socket. */ + /* FIXME: other applications, like squid, use an undocumented + _free_osfhnd free function. But this is not enough: The 'osfile' + flags for fd also needs to be cleared, but it is hard to access it. + Instead, here we just close twice the file descriptor. */ + if (closesocket (sock)) + { + set_winsock_errno (); + return -1; + } + else + { + /* This call frees the file descriptor and does a + CloseHandle ((HANDLE) _get_osfhandle (fd)), which fails. */ + _close (fd); + return 0; + } + } + else + /* Some other type of file descriptor. */ + return execute_close_hooks (remaining_list, primary, fd); +} + +static int +ioctl_fd_maybe_socket (const struct fd_hook *remaining_list, + gl_ioctl_fn primary, + int fd, int request, void *arg) +{ + SOCKET sock; + WSANETWORKEVENTS ev; + + /* Test whether fd refers to a socket. */ + sock = FD_TO_SOCKET (fd); + ev.lNetworkEvents = 0xDEADBEEF; + WSAEnumNetworkEvents (sock, NULL, &ev); + if (ev.lNetworkEvents != 0xDEADBEEF) + { + /* fd refers to a socket. */ + if (ioctlsocket (sock, request, arg) < 0) + { + set_winsock_errno (); + return -1; + } + else + return 0; + } + else + /* Some other type of file descriptor. */ + return execute_ioctl_hooks (remaining_list, primary, fd, request, arg); +} + +static struct fd_hook fd_sockets_hook; + +static int initialized_sockets_version /* = 0 */; + +#endif /* WINDOWS_SOCKETS */ + +int +gl_sockets_startup (int version _GL_UNUSED) +{ +#if WINDOWS_SOCKETS + if (version > initialized_sockets_version) + { + WSADATA data; + int err; + + err = WSAStartup (version, &data); + if (err != 0) + return 1; + + if (data.wVersion != version) + { + WSACleanup (); + return 2; + } + + if (initialized_sockets_version == 0) + register_fd_hook (close_fd_maybe_socket, ioctl_fd_maybe_socket, + &fd_sockets_hook); + + initialized_sockets_version = version; + } +#endif + + return 0; +} + +int +gl_sockets_cleanup (void) +{ +#if WINDOWS_SOCKETS + int err; + + initialized_sockets_version = 0; + + unregister_fd_hook (&fd_sockets_hook); + + err = WSACleanup (); + if (err != 0) + return 1; +#endif + + return 0; +} |