Il 01/10/2014 23:09, miny...@acm.org ha scritto:
> From: Corey Minyard <cminy...@mvista.com>
>
> Adds a "reconnect" option to socket backends that gives a reconnect
> timeout. This only applies to client sockets. If the other end
> of a socket closes the connection, qemu will attempt to reconnect
> after the given number of seconds.
>
> Signed-off-by: Corey Minyard <cminy...@mvista.com>
> ---
> qapi-schema.json | 15 ++++++----
> qemu-char.c | 88
> ++++++++++++++++++++++++++++++++++++++++++++++++++++----
> qemu-options.hx | 20 ++++++++-----
> 3 files changed, 105 insertions(+), 18 deletions(-)
>
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 4bfaf20..148097b 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -2651,14 +2651,19 @@
> # @nodelay: #optional set TCP_NODELAY socket option (default: false)
> # @telnet: #optional enable telnet protocol on server
> # sockets (default: false)
> +# @reconnect: #optional For a client socket, if a socket is disconnected,
> +# then attempt a reconnect after the given number of seconds.
> +# Setting this to zero disables this function. (default: 0)
> +# (Since: 2.2)
> #
> # Since: 1.4
> ##
> -{ 'type': 'ChardevSocket', 'data': { 'addr' : 'SocketAddress',
> - '*server' : 'bool',
> - '*wait' : 'bool',
> - '*nodelay' : 'bool',
> - '*telnet' : 'bool' } }
> +{ 'type': 'ChardevSocket', 'data': { 'addr' : 'SocketAddress',
> + '*server' : 'bool',
> + '*wait' : 'bool',
> + '*nodelay' : 'bool',
> + '*telnet' : 'bool',
> + '*reconnect' : 'int' } }
>
> ##
> # @ChardevUdp:
> diff --git a/qemu-char.c b/qemu-char.c
> index b118e88..f33173c 100644
> --- a/qemu-char.c
> +++ b/qemu-char.c
> @@ -2501,8 +2501,20 @@ typedef struct {
> SocketAddress *addr;
> bool is_listen;
> bool is_telnet;
> +
> + guint reconnect_timer;
> + int64_t reconnect_time;
> } TCPCharDriver;
>
> +static gboolean socket_reconnect_timeout(gpointer opaque);
> +
> +static void qemu_chr_socket_restart_timer(CharDriverState *chr)
> +{
> + TCPCharDriver *s = chr->opaque;
Please assert that s->connected == 0 here.
> + s->reconnect_timer = g_timeout_add_seconds(s->reconnect_time,
> + socket_reconnect_timeout,
> chr);
> +}
> +
> static gboolean tcp_chr_accept(GIOChannel *chan, GIOCondition cond, void
> *opaque);
>
> #ifndef _WIN32
> @@ -2784,6 +2796,9 @@ static void tcp_chr_disconnect(CharDriverState *chr)
> SocketAddress_to_str(chr->filename, CHR_MAX_FILENAME_SIZE,
> "disconnected:", s->addr, s->is_listen,
> s->is_telnet);
> qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
> + if (s->reconnect_time) {
> + qemu_chr_socket_restart_timer(chr);
> + }
> }
>
> static gboolean tcp_chr_read(GIOChannel *chan, GIOCondition cond, void
> *opaque)
> @@ -2964,6 +2979,10 @@ static void tcp_chr_close(CharDriverState *chr)
> TCPCharDriver *s = chr->opaque;
> int i;
>
> + if (s->reconnect_timer) {
> + g_source_remove(s->reconnect_timer);
> + s->reconnect_timer = 0;
> + }
> qapi_free_SocketAddress(s->addr);
> if (s->fd >= 0) {
> remove_fd_in_watch(chr);
> @@ -3013,7 +3032,28 @@ static bool
> qemu_chr_finish_socket_connection(CharDriverState *chr, int fd,
> tcp_chr_connect(chr);
> }
>
> - return chr;
> + return true;
As mentioned in patch 2, this should be done there.
> +}
> +
> +static void qemu_chr_socket_connected(int fd, void *opaque)
> +{
> + CharDriverState *chr = opaque;
> + TCPCharDriver *s = chr->opaque;
> + Error *err = NULL;
> +
> + if (fd >= 0) {
> + if (qemu_chr_finish_socket_connection(chr, fd, &err)) {
If the errp argument is removed in qemu_chr_finish_socket_connection...
> + return;
> + }
> + if (err) {
> + error_report("%s", error_get_pretty(err));
> + error_free(err);
> + }
> + closesocket(fd);
> + }
> +
> + s->connected = 0;
... and we are sure that s->connected is already 0, this function can be
simply
CharDriverState *chr = opaque;
if (fd < 0) {
qemu_chr_socket_restart_timer(chr);
return;
}
qemu_chr_finish_socket_connection(chr, fd);
I have no other comment. Everything here is basically rippling from the
observation that errp is unused after patch 4; sorry for not noticing
that earlier.
Paolo
> + qemu_chr_socket_restart_timer(chr);
> }
>
> static bool qemu_chr_open_socket_fd(CharDriverState *chr, Error **errp)
> @@ -3023,7 +3063,10 @@ static bool qemu_chr_open_socket_fd(CharDriverState
> *chr, Error **errp)
>
> if (s->is_listen) {
> fd = socket_listen(s->addr, errp);
> - } else {
> + } else if (s->reconnect_time) {
> + fd = socket_connect(s->addr, errp, qemu_chr_socket_connected, chr);
> + return fd >= 0;
> + } else {
> fd = socket_connect(s->addr, errp, NULL, NULL);
> }
> if (fd < 0) {
> @@ -3450,6 +3493,7 @@ static void qemu_chr_parse_socket(QemuOpts *opts,
> ChardevBackend *backend,
> bool is_waitconnect = is_listen && qemu_opt_get_bool(opts, "wait", true);
> bool is_telnet = qemu_opt_get_bool(opts, "telnet", false);
> bool do_nodelay = !qemu_opt_get_bool(opts, "delay", true);
> + int64_t reconnect = qemu_opt_get_number(opts, "reconnect", 0);
> const char *path = qemu_opt_get(opts, "path");
> const char *host = qemu_opt_get(opts, "host");
> const char *port = qemu_opt_get(opts, "port");
> @@ -3476,6 +3520,8 @@ static void qemu_chr_parse_socket(QemuOpts *opts,
> ChardevBackend *backend,
> backend->socket->telnet = is_telnet;
> backend->socket->has_wait = true;
> backend->socket->wait = is_waitconnect;
> + backend->socket->has_reconnect = true;
> + backend->socket->reconnect = reconnect;
>
> addr = g_new0(SocketAddress, 1);
> if (path) {
> @@ -3875,6 +3921,9 @@ QemuOptsList qemu_chardev_opts = {
> .name = "delay",
> .type = QEMU_OPT_BOOL,
> },{
> + .name = "reconnect",
> + .type = QEMU_OPT_NUMBER,
> + },{
> .name = "telnet",
> .type = QEMU_OPT_BOOL,
> },{
> @@ -4018,6 +4067,26 @@ static CharDriverState
> *qmp_chardev_open_parallel(ChardevHostdev *parallel,
>
> #endif /* WIN32 */
>
> +static gboolean socket_reconnect_timeout(gpointer opaque)
> +{
> + CharDriverState *chr = opaque;
> + TCPCharDriver *s = chr->opaque;
> + Error *err;
> +
> + s->reconnect_timer = 0;
> +
> + if (chr->be_open) {
> + return false;
> + }
> +
> + if (!qemu_chr_open_socket_fd(chr, &err)) {
> + error_report("Unable to connect to char device %s\n", chr->label);
> + qemu_chr_socket_restart_timer(chr);
> + }
> +
> + return false;
> +}
> +
> static CharDriverState *qmp_chardev_open_socket(ChardevSocket *sock,
> Error **errp)
> {
> @@ -4028,6 +4097,7 @@ static CharDriverState
> *qmp_chardev_open_socket(ChardevSocket *sock,
> bool is_listen = sock->has_server ? sock->server : true;
> bool is_telnet = sock->has_telnet ? sock->telnet : false;
> bool is_waitconnect = sock->has_wait ? sock->wait : false;
> + int64_t reconnect = sock->has_reconnect ? sock->reconnect : 0;
>
> chr = qemu_chr_alloc();
> s = g_malloc0(sizeof(TCPCharDriver));
> @@ -4060,13 +4130,19 @@ static CharDriverState
> *qmp_chardev_open_socket(ChardevSocket *sock,
> if (is_telnet) {
> s->do_telnetopt = 1;
> }
> + } else if (reconnect > 0) {
> + s->reconnect_time = reconnect;
> }
>
> if (!qemu_chr_open_socket_fd(chr, errp)) {
> - g_free(s);
> - g_free(chr->filename);
> - g_free(chr);
> - return NULL;
> + if (s->reconnect_time) {
> + qemu_chr_socket_restart_timer(chr);
> + } else {
> + g_free(s);
> + g_free(chr->filename);
> + g_free(chr);
> + return NULL;
> + }
> }
>
> if (is_listen && is_waitconnect) {
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 365b56c..22cf3b9 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -1930,9 +1930,9 @@ ETEXI
>
> DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
> "-chardev null,id=id[,mux=on|off]\n"
> - "-chardev
> socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay]\n"
> - " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
> - "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off]
> (unix)\n"
> + "-chardev
> socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
> + " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]
> (tcp)\n"
> + "-chardev
> socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]
> (unix)\n"
> "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
> " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
> "-chardev msmouse,id=id[,mux=on|off]\n"
> @@ -2004,7 +2004,7 @@ Options to each backend are described below.
> A void device. This device will not emit any data, and will drop any data it
> receives. The null backend does not take any options.
>
> -@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}]
> [,server] [,nowait] [,telnet]
> +@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}]
> [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}]
>
> Create a two-way stream socket, which can be either a TCP or a unix socket. A
> unix socket will be created if @option{path} is specified. Behaviour is
> @@ -2018,6 +2018,10 @@ connect to a listening socket.
> @option{telnet} specifies that traffic on the socket should interpret telnet
> escape sequences.
>
> +@option{reconnect} sets the timeout for reconnecting on non-server sockets
> when
> +the remote end goes away. qemu will delay this many seconds and then attempt
> +to reconnect. Zero disables reconnecting, and is the default.
> +
> TCP and unix socket options are given below:
>
> @table @option
> @@ -2687,14 +2691,16 @@ telnet on port 5555 to access the QEMU port.
> localhost 5555
> @end table
>
> -@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
> +@item
> tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
> The TCP Net Console has two modes of operation. It can send the serial
> I/O to a location or wait for a connection from a location. By default
> the TCP Net Console is sent to @var{host} at the @var{port}. If you use
> the @var{server} option QEMU will wait for a client socket application
> to connect to the port before continuing, unless the @code{nowait}
> option was specified. The @code{nodelay} option disables the Nagle buffering
> -algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
> +algorithm. The @code{reconnect} option only applies if @var{noserver} is
> +set, if the connection goes down it will attempt to reconnect at the
> +given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
> one TCP connection at a time is accepted. You can use @code{telnet} to
> connect to the corresponding character device.
> @table @code
> @@ -2715,7 +2721,7 @@ MAGIC_SYSRQ sequence if you use a telnet that supports
> sending the break
> sequence. Typically in unix telnet you do it with Control-] and then
> type "send break" followed by pressing the enter key.
>
> -@item unix:@var{path}[,server][,nowait]
> +@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
> A unix domain socket is used instead of a tcp socket. The option works the
> same as if you had specified @code{-serial tcp} except the unix domain socket
> @var{path} is used for connections.
>
