When QEMU is executed as part of a test case or from a script, it is
usually desirable to exit if the parent process terminates. This
ensures that "leaked" QEMU processes do not continue consuming resources
after their parent has died.
This patch adds the -chardev exit-on-eof option causing socket and pipe
chardevs to exit QEMU upon close. This happens when a parent process
deliberately closes its file descriptor but also when the kernel cleans
up a crashed process.
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
include/sysemu/char.h | 1 +
qapi-schema.json | 23 ++++++++++++++++-------
qemu-char.c | 33 +++++++++++++++++++++++++++------
qemu-options.hx | 19 +++++++++++++------
4 files changed, 57 insertions(+), 19 deletions(-)
diff --git a/include/sysemu/char.h b/include/sysemu/char.h
index 0bbd631..382b320 100644
--- a/include/sysemu/char.h
+++ b/include/sysemu/char.h
@@ -86,6 +86,7 @@ struct CharDriverState {
guint fd_in_tag;
QemuOpts *opts;
QTAILQ_ENTRY(CharDriverState) next;
+ bool exit_on_eof;
};
/**
diff --git a/qapi-schema.json b/qapi-schema.json
index b11aad2..9b13da1 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2630,10 +2630,13 @@
# @device: The name of the special file for the device,
# i.e. /dev/ttyS0 on Unix or COM1: on Windows
# @type: What kind of device this is.
+# @exit-on-eof: #optional terminate when other side closes the pipe
+# (default: false, since: 2.2)
#
# Since: 1.4
##
-{ 'type': 'ChardevHostdev', 'data': { 'device' : 'str' } }
+{ 'type': 'ChardevHostdev', 'data': { 'device' : 'str',
+ '*exit-on-eof' : 'bool' } }
##
# @ChardevSocket:
@@ -2648,14 +2651,17 @@
# @nodelay: #optional set TCP_NODELAY socket option (default: false)
# @telnet: #optional enable telnet protocol on server
# sockets (default: false)
+# @exit-on-eof: #optional terminate when other side closes socket
+# (default: false, 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',
+ '*exit-on-eof' : 'bool' } }
##
# @ChardevUdp:
@@ -2689,10 +2695,13 @@
# @signal: #optional Allow signals (such as SIGINT triggered by ^C)
# be delivered to qemu. Default: true in -nographic mode,
# false otherwise.
+# @exit-on-eof: #optional terminate when other side sends EOF
+# (default: false, since: 2.2)
#
# Since: 1.5
##
-{ 'type': 'ChardevStdio', 'data': { '*signal' : 'bool' } }
+{ 'type': 'ChardevStdio', 'data': { '*signal' : 'bool',
+ '*exit-on-eof' : 'bool' } }
##
# @ChardevSpiceChannel:
diff --git a/qemu-char.c b/qemu-char.c
index 7acc03f..1974b8f 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -110,9 +110,15 @@ void qemu_chr_be_event(CharDriverState *s, int event)
break;
}
- if (!s->chr_event)
- return;
- s->chr_event(s->handler_opaque, event);
+ if (s->chr_event) {
+ s->chr_event(s->handler_opaque, event);
+ }
+
+ if (s->exit_on_eof && event == CHR_EVENT_CLOSED) {
+ fprintf(stderr, "qemu: terminating due to eof on chardev '%s'\n",
+ s->label);
+ qemu_system_shutdown_force();
+ }
}
void qemu_chr_be_generic_open(CharDriverState *s)
@@ -991,6 +997,7 @@ static CharDriverState *qemu_chr_open_pipe(ChardevHostdev
*opts)
int fd_in, fd_out;
char filename_in[256], filename_out[256];
const char *filename = opts->device;
+ CharDriverState *chr;
if (filename == NULL) {
fprintf(stderr, "chardev: pipe: no filename given\n");
@@ -1011,7 +1018,9 @@ static CharDriverState *qemu_chr_open_pipe(ChardevHostdev
*opts)
return NULL;
}
}
- return qemu_chr_open_fd(fd_in, fd_out);
+ chr = qemu_chr_open_fd(fd_in, fd_out);
+ chr->exit_on_eof = opts->has_exit_on_eof && opts->exit_on_eof;
+ return chr;
}
/* init terminal so that we can grab keys */
@@ -2893,6 +2902,7 @@ static void tcp_chr_close(CharDriverState *chr)
static CharDriverState *qemu_chr_open_socket_fd(int fd, bool do_nodelay,
bool is_listen, bool is_telnet,
bool is_waitconnect,
+ bool is_exit_on_eof,
Error **errp)
{
CharDriverState *chr = NULL;
@@ -2955,6 +2965,7 @@ static CharDriverState *qemu_chr_open_socket_fd(int fd,
bool do_nodelay,
chr->chr_update_read_handler = tcp_chr_update_read_handler;
/* be isn't opened until we get a connection */
chr->explicit_be_open = true;
+ chr->exit_on_eof = is_exit_on_eof;
if (is_listen) {
s->listen_fd = fd;
@@ -2991,6 +3002,7 @@ static CharDriverState *qemu_chr_open_socket(QemuOpts
*opts)
bool is_telnet = qemu_opt_get_bool(opts, "telnet", false);
bool do_nodelay = !qemu_opt_get_bool(opts, "delay", true);
bool is_unix = qemu_opt_get(opts, "path") != NULL;
+ bool is_exit_on_eof = qemu_opt_get_bool(opts, "exit-on-eof", false);
if (is_unix) {
if (is_listen) {
@@ -3013,7 +3025,7 @@ static CharDriverState *qemu_chr_open_socket(QemuOpts
*opts)
qemu_set_nonblock(fd);
chr = qemu_chr_open_socket_fd(fd, do_nodelay, is_listen, is_telnet,
- is_waitconnect, &local_err);
+ is_waitconnect, is_exit_on_eof, &local_err);
if (local_err) {
goto fail;
}
@@ -3376,6 +3388,8 @@ static void qemu_chr_parse_stdio(QemuOpts *opts,
ChardevBackend *backend,
backend->stdio = g_new0(ChardevStdio, 1);
backend->stdio->has_signal = true;
backend->stdio->signal = qemu_opt_get_bool(opts, "signal", true);
+ backend->stdio->has_exit_on_eof = true;
+ backend->stdio->exit_on_eof = qemu_opt_get_bool(opts, "exit-on-eof",
false);
}
static void qemu_chr_parse_serial(QemuOpts *opts, ChardevBackend *backend,
@@ -3415,6 +3429,8 @@ static void qemu_chr_parse_pipe(QemuOpts *opts,
ChardevBackend *backend,
}
backend->pipe = g_new0(ChardevHostdev, 1);
backend->pipe->device = g_strdup(device);
+ backend->pipe->has_exit_on_eof = true;
+ backend->pipe->exit_on_eof = qemu_opt_get_bool(opts, "exit-on-eof", false);
}
static void qemu_chr_parse_ringbuf(QemuOpts *opts, ChardevBackend *backend,
@@ -3848,6 +3864,9 @@ QemuOptsList qemu_chardev_opts = {
},{
.name = "chardev",
.type = QEMU_OPT_STRING,
+ },{
+ .name = "exit-on-eof",
+ .type = QEMU_OPT_BOOL,
},
{ /* end of list */ }
},
@@ -3967,6 +3986,7 @@ 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;
+ bool is_exit_on_eof = sock->has_exit_on_eof ? sock->exit_on_eof : false;
int fd;
if (is_listen) {
@@ -3978,7 +3998,8 @@ static CharDriverState
*qmp_chardev_open_socket(ChardevSocket *sock,
return NULL;
}
return qemu_chr_open_socket_fd(fd, do_nodelay, is_listen,
- is_telnet, is_waitconnect, errp);
+ is_telnet, is_waitconnect,
+ is_exit_on_eof, errp);
}
static CharDriverState *qmp_chardev_open_udp(ChardevUdp *udp,
diff --git a/qemu-options.hx b/qemu-options.hx
index 9e54686..4b4da4f 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1927,8 +1927,9 @@ ETEXI
DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
"-chardev null,id=id[,mux=on|off]\n"
"-chardev
socket,id=id[,host=host],port=host[,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"
+ " [,server][,nowait][,telnet][,mux=on|off][,exit-on-eof] (tcp)\n"
+ "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off]\n"
+ " [,exit-on-eof] (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"
@@ -1936,13 +1937,13 @@ DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
" [,mux=on|off]\n"
"-chardev ringbuf,id=id[,size=size]\n"
"-chardev file,id=id,path=path[,mux=on|off]\n"
- "-chardev pipe,id=id,path=path[,mux=on|off]\n"
+ "-chardev pipe,id=id,path=path[,mux=on|off][,exit-on-eof]\n"
#ifdef _WIN32
"-chardev console,id=id[,mux=on|off]\n"
"-chardev serial,id=id,path=path[,mux=on|off]\n"
#else
"-chardev pty,id=id[,mux=on|off]\n"
- "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
+ "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,exit-on-eof]\n"
#endif
#ifdef CONFIG_BRLAPI
"-chardev braille,id=id[,mux=on|off]\n"
@@ -2000,7 +2001,7 @@ 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] [,exit-on-eof]
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
@@ -2014,6 +2015,8 @@ connect to a listening socket.
@option{telnet} specifies that traffic on the socket should interpret telnet
escape sequences.
+@option{exit-on-eof} specifies that QEMU should terminate upon disconnect
+
TCP and unix socket options are given below:
@table @option
@@ -2094,7 +2097,7 @@ Log all traffic received from the guest to a file.
created if it does not already exist, and overwritten if it does. @option{path}
is required.
-@item -chardev pipe ,id=@var{id} ,path=@var{path}
+@item -chardev pipe ,id=@var{id} ,path=@var{path} [,exit-on-eof]
Create a two-way connection to the guest. The behaviour differs slightly
between
Windows hosts and other hosts:
@@ -2111,6 +2114,8 @@ be present.
@option{path} forms part of the pipe path as described above. @option{path} is
required.
+@option{exit-on-eof} specifies that QEMU should terminate upon disconnect
+
@item -chardev console ,id=@var{id}
Send traffic from the guest to QEMU's standard output. @option{console} does
not
@@ -2141,6 +2146,8 @@ Connect to standard input and standard output of the QEMU
process.
exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
default, use @option{signal=off} to disable it.
+@option{exit-on-eof} specifies that QEMU should terminate upon EOF
+
@option{stdio} is not available on Windows hosts.
@item -chardev braille ,id=@var{id}
--
1.9.3
