[Libguestfs] Libguestfs (1.22.6) driver/changes for mingw/win32
Daniel P. Berrange
berrange at redhat.com
Mon Feb 17 14:40:42 UTC 2014
On Mon, Feb 17, 2014 at 01:53:02PM +0000, Richard W.M. Jones wrote:
> On Thu, Feb 13, 2014 at 04:54:09PM +0200, Or Goshen wrote:
> > Hi,
> >
> > I attached the changes I made to a vanilla libguestfs-1.22.6 in order to
> > make it work in mingw/win32.
> > Added is also the patch required to make QEMU compatible (add a command to
> > QMP that lists the supported devices (the regilat way you do it print it to
> > stderr, which is difficult to redirect in win32)).
>
> A couple of points first:
>
> - You need to start using git.
>
> - You need to develop against the git head, not the old 1.22 branch.
>
> I took the tarball and turned it into a git commit, which I then
> cherry picked on top of head. (Except for 'bootstrap' which seems to
> be a completely rewritten file -- so I created it as
> 'bootstrap.win32').
>
> This is attached so you can take it from here. As this was mostly an
> automatic process -- git did the hard work, I just resolved a few
> things that git could not resolve -- you need to check carefully that
> this patch still works.
>
> About the patch itself:
>
> The patch looks fairly sensible. There's some tidying up that could
> be done, and it would be nice to confine more of the changes so they
> don't affect the main code. But there's nothing here that can't be
> pushed upstream in some form, after a proper review and more testing.
IMHO most of the diff that involves socket accept/select/read/write
and the Windows HANDLE <-> FD conversion looks really dubious and is
likely redundant. If you're using enough of the GNULIB modules, then
it should make all the WINSOCK awfulness go away such that normal
POSIX calls and poll/select stuff 'just works'.
The main missing socket functionality in Win32 that GNULIB doesn't
solve is a socketpair() impl, for which localhost bound IPv4 socket,
is normal.
GNULIB also solves the O_NONBLOCK vs FIONBIO problem too via
its 'set_nonblocking_flag' function.
IOW from here onwards:
> diff --git a/src/conn-socket.c b/src/conn-socket.c
> index fe3ca04..e21fde7 100644
> --- a/src/conn-socket.c
> +++ b/src/conn-socket.c
> @@ -20,16 +20,22 @@
>
> #include <config.h>
>
> -#include <stdio.h>
> -#include <stdlib.h>
> -#include <string.h>
> +#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
> +#include <io.h>
> +#include <Winsock2.h>
> +#else
> #include <unistd.h>
> #include <fcntl.h>
> -#include <errno.h>
> #include <poll.h>
> #include <sys/stat.h>
> #include <sys/socket.h>
> #include <sys/types.h>
> +#endif
> +
> +#include <string.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <errno.h>
> #include <assert.h>
>
> #include "guestfs.h"
> @@ -47,8 +53,12 @@ struct connection_socket {
> int daemon_accept_sock;
> };
>
> +#define FD_TO_SOCKET(fd) ((SOCKET) _get_osfhandle ((fd)))
> +#define SOCKET_TO_FD(fh) (_open_osfhandle ((intptr_t) (fh), O_RDWR | O_BINARY))
> +
> static int handle_log_message (guestfs_h *g, struct connection_socket *conn);
>
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> static int
> accept_connection (guestfs_h *g, struct connection *connv)
> {
> @@ -125,12 +135,75 @@ accept_connection (guestfs_h *g, struct connection *connv)
> /* Make sure the new socket is non-blocking. */
> if (fcntl (conn->daemon_sock, F_SETFL, O_NONBLOCK) == -1) {
> perrorf (g, "accept_connection: fcntl");
> - return -1;
> + return -1;
> }
> -
> return 1;
> }
> +#else
> +static int accept_connection(guestfs_h *g, struct connection *connv) {
> + struct connection_socket *conn = (struct connection_socket *) connv;
> + SOCKET sock = INVALID_SOCKET;
>
> + if (conn->daemon_accept_sock == -1) {
> + error(g, _("accept_connection called twice"));
> + return -1;
> + }
> +
> + while (sock == INVALID_SOCKET) {
> + int r;
> + fd_set rfds;
> +
> + FD_ZERO (&rfds);
> +
> + FD_SET (FD_TO_SOCKET(conn->daemon_accept_sock), &rfds);
> + if (conn->console_sock >= 0) {
> + FD_SET (FD_TO_SOCKET(conn->console_sock), &rfds);
> + }
> +
> + r = select(0, &rfds, NULL, NULL, NULL);
> + if (r > 0) {
> + if (FD_ISSET(FD_TO_SOCKET(conn->console_sock), &rfds)) {
> + r = handle_log_message (g, conn);
> + if (r <= 0)
> + return r;
> + }
> +
> + if (FD_ISSET(FD_TO_SOCKET(conn->daemon_accept_sock), &rfds)) {
> + sock = accept(FD_TO_SOCKET(conn->daemon_accept_sock), NULL, NULL);
> + if (sock == INVALID_SOCKET) {
> + if (errno == EINTR || errno == EAGAIN)
> + continue;
> + perrorf(g, "accept_connection: accept");
> + return -1;
> + }
> + }
> + } else if (r == SOCKET_ERROR) {
> + errno = WSAGetLastError();
> + if (errno == EINTR || errno == EAGAIN)
> + continue;
> + perrorf (g, "accept_connection: select");
> + return -1;
> + }
> + }
> +
> + /* Got a connection and accepted it, so update the connection's
> + * internal status.
> + */
> + closesocket(FD_TO_SOCKET(conn->daemon_accept_sock));
> + conn->daemon_accept_sock = -1;
> + conn->daemon_sock = sock;
> +
> + /* Make sure the new socket is non-blocking. */
> + u_long iMode = 0;
> + if (ioctlsocket(conn->daemon_sock, FIONBIO, &iMode) == SOCKET_ERROR) {
> + perrorf(g, "accept_connection: ioctlsocket");
> + return -1;
> + }
> + return 1;
> +}
> +#endif
> +
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> static ssize_t
> read_data (guestfs_h *g, struct connection *connv, void *bufv, size_t len)
> {
> @@ -205,7 +278,75 @@ read_data (guestfs_h *g, struct connection *connv, void *bufv, size_t len)
>
> return original_len;
> }
> +#else
> +static ssize_t
> +read_data (guestfs_h *g, struct connection *connv, void *bufv, size_t len)
> +{
> + char *buf = bufv;
> + struct connection_socket *conn = (struct connection_socket *) connv;
> + size_t original_len = len;
>
> + if (conn->daemon_sock == -1) {
> + error (g, _("read_data: socket not connected"));
> + return -1;
> + }
> +
> + while (len > 0) {
> + int r;
> + fd_set rfds;
> +
> + FD_ZERO (&rfds);
> +
> + FD_SET (conn->daemon_sock, &rfds);
> + if (conn->console_sock >= 0)
> + FD_SET (FD_TO_SOCKET(conn->console_sock), &rfds);
> +
> + r = select(0, &rfds, NULL, NULL, NULL);
> + if (r > 0) {
> + if (FD_ISSET(FD_TO_SOCKET(conn->console_sock), &rfds)) {
> + r = handle_log_message (g, conn);
> + if (r <= 0)
> + return r;
> + }
> +
> + if (FD_ISSET(conn->daemon_sock, &rfds)) {
> + int n = recv(conn->daemon_sock, buf, len, 0);
> + if (n == -1) {
> + if (errno == EINTR || errno == EAGAIN)
> + continue;
> + if (errno == ECONNRESET) /* essentially the same as EOF case */
> + goto closed;
> + perrorf(g, "read_data: read");
> + return -1;
> + }
> + if (n == 0) {
> + closed:
> + /* Even though qemu has gone away, there could be more log
> + * messages in the console socket buffer in the kernel. Read
> + * them out here.
> + */
> + if (g->verbose && conn->console_sock >= 0) {
> + while (handle_log_message(g, conn) == 1);
> + }
> + return 0;
> + }
> +
> + buf += n;
> + len -= n;
> + }
> + } else if (r == -1) {
> + if (errno == EINTR || errno == EAGAIN)
> + continue;
> + perrorf (g, "read_data: select");
> + return -1;
> + }
> + }
> +
> + return original_len;
> +}
> +#endif
> +
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> static int
> can_read_data (guestfs_h *g, struct connection *connv)
> {
> @@ -233,7 +374,40 @@ can_read_data (guestfs_h *g, struct connection *connv)
>
> return (fd.revents & POLLIN) != 0 ? 1 : 0;
> }
> +#else
> +static int
> +can_read_data (guestfs_h *g, struct connection *connv)
> +{
> + struct connection_socket *conn = (struct connection_socket *) connv;
> + int r;
> + fd_set rfds;
> + //struct timeval tv0 = { .tv_sec = 0, .tv_usec = 0};
> + const struct timeval timeout = {0, 0};
>
> +
> + if (conn->daemon_sock == -1) {
> + error (g, _("can_read_data: socket not connected"));
> + return -1;
> + }
> +
> + FD_ZERO (&rfds);
> +
> + FD_SET (conn->daemon_sock, &rfds);
> +
> + again:
> + r = select(0, &rfds, NULL, NULL, &timeout);
> + if (r == -1) {
> + if (errno == EINTR || errno == EAGAIN)
> + goto again;
> + perrorf (g, "can_read_data: select");
> + return -1;
> + }
> +
> + return FD_ISSET(conn->daemon_sock, &rfds) ? 1 : 0;
> +}
> +#endif
> +
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> static ssize_t
> write_data (guestfs_h *g, struct connection *connv,
> const void *bufv, size_t len)
> @@ -263,7 +437,8 @@ write_data (guestfs_h *g, struct connection *connv,
> nfds++;
> }
>
> - r = poll (fds, nfds, -1);
> + r = 1;//poll (fds, nfds, -1);
> + fds[0].revents = POLLOUT;
> if (r == -1) {
> if (errno == EINTR || errno == EAGAIN)
> continue;
> @@ -297,6 +472,64 @@ write_data (guestfs_h *g, struct connection *connv,
>
> return original_len;
> }
> +#else
> +static ssize_t
> +write_data (guestfs_h *g, struct connection *connv,
> + const void *bufv, size_t len)
> +{
> + const char *buf = bufv;
> + struct connection_socket *conn = (struct connection_socket *) connv;
> + size_t original_len = len;
> +
> + if (conn->daemon_sock == -1) {
> + error (g, _("write_data: socket not connected"));
> + return -1;
> + }
> +
> + while (len > 0) {
> + int r;
> + fd_set rfds, wfds;
> +
> + FD_ZERO (&rfds);
> + FD_ZERO (&wfds);
> +
> + FD_SET (conn->daemon_sock, &wfds);
> + if (conn->console_sock >= 0)
> + FD_SET (FD_TO_SOCKET(conn->console_sock), &rfds);
> +
> + r = select(0, &rfds, &wfds, NULL, NULL);
> + if (r > 0) {
> + if (FD_ISSET(FD_TO_SOCKET(conn->console_sock), &rfds)) {
> + r = handle_log_message (g, conn);
> + if (r <= 0)
> + return r;
> + }
> +
> + if (FD_ISSET(conn->daemon_sock, &wfds)) {
> + int n = send(conn->daemon_sock, buf, len, 0);
> + if (n == -1) {
> + if (errno == EINTR || errno == EAGAIN)
> + continue;
> + if (errno == EPIPE) /* Disconnected from guest (RHBZ#508713). */
> + return 0;
> + perrorf(g, "write_data: write");
> + return -1;
> + }
> +
> + buf += n;
> + len -= n;
> + }
> + } else if (r == -1) {
> + if (errno == EINTR || errno == EAGAIN)
> + continue;
> + perrorf (g, "write_data: select");
> + return -1;
> + }
> + }
> +
> + return original_len;
> +}
> +#endif
>
> /* This is called if conn->console_sock becomes ready to read while we
> * are doing one of the connection operations above. It reads and
> @@ -326,7 +559,9 @@ handle_log_message (guestfs_h *g,
> * based console (not yet implemented) we may be able to remove
> * this. XXX"
> */
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> usleep (1000);
> +#endif
>
> n = read (conn->console_sock, buf, sizeof buf);
> if (n == 0)
> @@ -366,6 +601,7 @@ handle_log_message (guestfs_h *g,
> return 1;
> }
>
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> static void
> free_conn_socket (guestfs_h *g, struct connection *connv)
> {
> @@ -380,6 +616,22 @@ free_conn_socket (guestfs_h *g, struct connection *connv)
>
> free (conn);
> }
> +#else
> +static void
> +free_conn_socket (guestfs_h *g, struct connection *connv)
> +{
> + struct connection_socket *conn = (struct connection_socket *) connv;
> +
> + if (conn->console_sock >= 0)
> + closesocket (FD_TO_SOCKET(conn->console_sock));
> + if (conn->daemon_sock >= 0)
> + closesocket (conn->daemon_sock);
> + if (conn->daemon_accept_sock >= 0)
> + closesocket (FD_TO_SOCKET(conn->daemon_accept_sock));
> +
> + free (conn);
> +}
> +#endif
>
> static struct connection_ops ops = {
> .free_connection = free_conn_socket,
> @@ -407,13 +659,23 @@ guestfs___new_conn_socket_listening (guestfs_h *g,
>
> assert (daemon_accept_sock >= 0);
>
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> if (fcntl (daemon_accept_sock, F_SETFL, O_NONBLOCK) == -1) {
> +#else
> + u_long iMode = 0;
> + if (ioctlsocket(FD_TO_SOCKET(daemon_accept_sock), FIONBIO, &iMode) == SOCKET_ERROR) {
> +#endif
> perrorf (g, "new_conn_socket_listening: fcntl");
> return NULL;
> }
>
> if (console_sock >= 0) {
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> if (fcntl (console_sock, F_SETFL, O_NONBLOCK) == -1) {
> +#else
> + u_long iMode1 = 0;
> + if (ioctlsocket(FD_TO_SOCKET(console_sock), FIONBIO, &iMode1) == SOCKET_ERROR) {
> +#endif
> perrorf (g, "new_conn_socket_listening: fcntl");
> return NULL;
> }
> @@ -446,13 +708,23 @@ guestfs___new_conn_socket_connected (guestfs_h *g,
>
> assert (daemon_sock >= 0);
>
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> if (fcntl (daemon_sock, F_SETFL, O_NONBLOCK) == -1) {
> +#else
> + u_long iMode = 0;
> + if (ioctlsocket(FD_TO_SOCKET(daemon_sock), FIONBIO, &iMode) == SOCKET_ERROR) {
> +#endif
> perrorf (g, "new_conn_socket_connected: fcntl");
> return NULL;
> }
>
> if (console_sock >= 0) {
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> if (fcntl (console_sock, F_SETFL, O_NONBLOCK) == -1) {
> +#else
> + u_long iMode1 = 0;
> + if (ioctlsocket(FD_TO_SOCKET(console_sock), FIONBIO, &iMode1) == SOCKET_ERROR) {
> +#endif
> perrorf (g, "new_conn_socket_connected: fcntl");
> return NULL;
> }
...to here should pretty much all be redundant.
The socketpair code in this file:
> diff --git a/src/launch-direct.c b/src/launch-direct.c
> index 964a507..1bc33c5 100644
> --- a/src/launch-direct.c
> +++ b/src/launch-direct.c
> @@ -257,6 +257,90 @@ debian_kvm_warning (guestfs_h *g)
> }
>
> static int
> +get_listener_socket()
> +{
> + union
> + {
> + struct sockaddr_in inaddr;
> + struct sockaddr addr;
> + } a;
> +
> + int listener;
> + int reuse = 1;
> +
> + listener = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
> + if (listener == -1)
> + return -1;
> +
> + memset(&a, 0, sizeof(a));
> + a.inaddr.sin_family = AF_INET;
> + a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
> + a.inaddr.sin_port = 0;
> +
> + if (setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, (char*)&reuse, (socklen_t)sizeof(reuse)) == -1)
> + goto error1;
> +
> + if (bind(listener, &a.addr, sizeof(a.inaddr)) == -1)
> + goto error1;
> +
> + return listener;
> +
> +error1:
> + close(listener);
> +
> + return -1;
> +}
> +
> +static int
> +mingw_socketpair(int socks[2])
> +{
> + union
> + {
> + struct sockaddr_in inaddr;
> + struct sockaddr addr;
> + } a;
> +
> + socklen_t addrlen;
> + int listener = get_listener_socket();
> + if (listener == -1)
> + return -1;
> +
> + memset(&a, 0, sizeof(a));
> +
> + if (getsockname(listener, &a.addr, &addrlen) == -1)
> + goto error1;
> +
> + a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
> + a.inaddr.sin_family = AF_INET;
> +
> + if (listen(listener, 1) == -1)
> + goto error1;
> +
> + socks[0] = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
> + if (socks[0] == -1)
> + goto error1;
> +
> + if (connect(socks[0], &a.addr, sizeof(a.inaddr)) == -1)
> + goto error2;
> +
> + socks[1] = accept(listener, NULL, NULL);
> + if (socks[1] == -1)
> + goto error2;
> +
> + close(listener);
> +
> + return 0;
> +
> +error2:
> + close(socks[0]);
> +
> +error1:
> + close(listener);
> +
> + return -1;
> +}
Seems to have been copied again in this file:
> diff --git a/src/launch-mingw.c b/src/launch-mingw.c
> new file mode 100644
> index 0000000..b944644
> --- /dev/null
> +++ b/src/launch-mingw.c
> +
> +#define QEMU_PORT 0
> +static int
> +get_listener_socket()
> +{
> + union
> + {
> + struct sockaddr_in inaddr;
> + struct sockaddr addr;
> + } a;
> +
> + int listener;
> + int reuse = 1;
> +
> + listener = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
> + if (listener == -1)
> + return -1;
> +
> + memset(&a, 0, sizeof(a));
> + a.inaddr.sin_family = AF_INET;
> + a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
> + a.inaddr.sin_port = 0;//htons(QEMU_PORT);
> +
> + if (setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, (char*)&reuse, (socklen_t)sizeof(reuse)) == -1)
> + goto error1;
> +
> + if (bind(listener, &a.addr, sizeof(a.inaddr)) == -1)
> + goto error1;
> +
> + return listener;
> +
> +error1:
> + close(listener);
> +
> + return -1;
> +}
> +
> +static int
> +mingw_socketpair(int socks[2])
> +{
> + union
> + {
> + struct sockaddr_in inaddr;
> + struct sockaddr addr;
> + } a;
> +
> + socklen_t addrlen = sizeof a.addr;
> + int listener;
> + int reuse = 1;
> +
> + listener = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
> + if (listener == -1)
> + return -1;
> +
> + memset(&a, 0, sizeof(a));
> + a.inaddr.sin_family = AF_INET;
> + a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
> + a.inaddr.sin_port = 0;
> +
> + if (setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, (char*)&reuse, (socklen_t)sizeof(reuse)) == -1)
> + goto error1;
> +
> + if (bind(listener, &a.addr, sizeof(a.inaddr)) == -1)
> + goto error1;
> +
> + if (getsockname(listener, &a.addr, &addrlen) == -1)
> + goto error1;
> +
> + // port number for console to listen to
> + int port = ntohs(a.inaddr.sin_port);
> +
> + if (listen(listener, 1) == -1)
> + goto error1;
> +
> + a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
> + a.inaddr.sin_family = AF_INET;
> +
> + socks[0] = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
> + if (socks[0] == -1)
> + goto error1;
> +
> + if (connect(socks[0], &a.addr, sizeof(a.inaddr)) == -1)
> + goto error2;
> +
> + socks[1] = accept(listener, NULL, NULL);
> + if (socks[1] == -1)
> + goto error2;
> +
> + close(listener);
> +
> + return 0;
> +
> +error2:
> + close(socks[0]);
> +
> +error1:
> + close(listener);
> +
> + return -1;
> +}
> +
> diff --git a/src/proto.c b/src/proto.c
> index 8001c8c..4744b37 100644
> --- a/src/proto.c
> +++ b/src/proto.c
> @@ -328,7 +326,11 @@ guestfs___send_file (guestfs_h *g, const char *filename)
>
> g->user_cancel = 0;
>
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> fd = open (filename, O_RDONLY|O_CLOEXEC);
> +#else
> + fd = _open (filename, _O_RDONLY|_O_BINARY|_O_NOINHERIT|_O_SEQUENTIAL);
> +#endif
> if (fd == -1) {
> perrorf (g, "open: %s", filename);
> send_file_cancellation (g);
> @@ -339,7 +341,11 @@ guestfs___send_file (guestfs_h *g, const char *filename)
>
> /* Send file in chunked encoding. */
> while (!g->user_cancel) {
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> r = read (fd, buf, sizeof buf);
> +#else
> + r = _read (fd, buf, sizeof buf);
> +#endif
> if (r == -1 && (errno == EINTR || errno == EAGAIN))
> continue;
> if (r <= 0) break;
> @@ -370,7 +376,11 @@ guestfs___send_file (guestfs_h *g, const char *filename)
> /* End of file, but before we send that, we need to close
> * the file and check for errors.
> */
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> if (close (fd) == -1) {
> +#else
> + if (_close (fd) == -1) {
> +#endif
> perrorf (g, "close: %s", filename);
> send_file_cancellation (g);
> return -1;
> @@ -734,7 +744,11 @@ xwrite (int fd, const void *v_buf, size_t len)
> int r;
>
> while (len > 0) {
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> r = write (fd, buf, len);
> +#else
> + r = _write (fd, buf, len);
> +#endif
> if (r == -1)
> return -1;
>
> @@ -756,7 +770,11 @@ guestfs___recv_file (guestfs_h *g, const char *filename)
>
> g->user_cancel = 0;
>
> +#if (!defined _WIN32 && !defined __WIN32__) || defined __CYGWIN__
> fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY|O_CLOEXEC, 0666);
> +#else
> + fd = _open (filename, _O_WRONLY|_O_CREAT|_O_BINARY|_O_TRUNC|_O_NOINHERIT, 0666);
> +#endif
> if (fd == -1) {
> perrorf (g, "open: %s", filename);
> goto cancel;
Conditionally calling the versions with _ seems pretty dubious too
Regards,
Daniel
--
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