Il 22/09/2014 01:04, 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>
Comments inline.
> ---
> qapi-schema.json | 14 +++++----
> qemu-char.c | 89
> ++++++++++++++++++++++++++++++++++++++++++++++++++++----
> qemu-options.hx | 20 ++++++++-----
> 3 files changed, 106 insertions(+), 17 deletions(-)
>
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 689b548..79f7a07 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -2648,14 +2648,18 @@
> # @nodelay: #optional set TCP_NODELAY socket option (default: false)
> # @telnet: #optional enable telnet protocol on server
> # sockets (default: false)
> +# @reconnect: #optional If not a server socket, if the socket disconnect
> +# then reconnect after the given number of seconds. Setting
> +# 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 8418e33..eefebd4 100644
> --- a/qemu-char.c
> +++ b/qemu-char.c
> @@ -2493,8 +2493,20 @@ 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;
> + 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
> @@ -2776,6 +2788,9 @@ 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)
> @@ -2956,6 +2971,9 @@ static void tcp_chr_close(CharDriverState *chr)
> TCPCharDriver *s = chr->opaque;
> int i;
>
> + if (s->reconnect_timer) {
> + g_source_remove(s->reconnect_timer);
Please add "s->reconnect_timer = 0;" here for easier debugging.
> + }
> qapi_free_SocketAddress(s->addr);
> if (s->fd >= 0) {
> remove_fd_in_watch(chr);
> @@ -3005,7 +3023,28 @@ static bool
> qemu_chr_finish_socket_connection(CharDriverState *chr, int fd,
> tcp_chr_connect(chr);
> }
>
> - return chr;
> + return true;
> +}
> +
> +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)) {
> + return;
> + }
> + if (err) {
> + error_report("%s", error_get_pretty(err));
> + error_free(err);
> + }
> + closesocket(fd);
> + }
> +
> + s->connected = 0;
> + qemu_chr_socket_restart_timer(chr);
> }
>
> static bool qemu_chr_open_socket_fd(CharDriverState *chr, Error **errp)
> @@ -3013,6 +3052,11 @@ static bool qemu_chr_open_socket_fd(CharDriverState
> *chr, Error **errp)
> TCPCharDriver *s = chr->opaque;
> int fd;
>
> + if (s->reconnect_time) {
> + fd = socket_connect(s->addr, errp, qemu_chr_socket_connected, chr);
> + return (fd >= 0);
> + }
The placement of this condition looks weird...
You're missing a check somewhere that reconnect is not specified
together with listen. Please add it, and move the condition in the
"else" side of the "if" just below.
> if (s->is_listen) {
> fd = socket_listen(s->addr, errp);
> } else {
> @@ -3442,6 +3486,7 @@ 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");
> @@ -4020,6 +4090,7 @@ 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));
> @@ -4036,6 +4107,8 @@ static CharDriverState
> *qmp_chardev_open_socket(ChardevSocket *sock,
> s->is_telnet = is_telnet;
> s->do_nodelay = do_nodelay;
> qapi_copy_SocketAddress(&s->addr, sock->addr);
> + s->reconnect_timer = 0;
> + s->reconnect_time = 0;
Not needed after g_malloc0.
>
> chr->opaque = s;
> chr->chr_write = tcp_chr_write;
> @@ -4057,13 +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..0cb856f 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=reconnect_time]\n"
s/reconnect_time/seconds/
> + "
> [,server][,nowait][,telnet][,reconnect=reconnect_time][,mux=on|off] (tcp)\n"
> + "-chardev
> socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=reconnect_time][,mux=on|off]
> (unix)\n"
s/reconnect_time/seconds/
> "-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=reconnect_time]
s/reconnect_time/@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=reconnect_time]
s/reconnect_time/@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=reconnect_time]
s/reconnect_time/@var{seconds}/
Paolo
> 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.
>
