Commit 0983f5e6 authored by Daniel P. Berrangé's avatar Daniel P. Berrangé
Browse files

sockets: allow port to be NULL when listening on IP address 



If the port in the SocketAddress struct is NULL, it can allow
the kernel to automatically select a free port. This is useful
in particular in unit tests to avoid a race trying to find a
free port to run a test case on.

Signed-off-by: default avatarDaniel P. Berrange <berrange@redhat.com>
parent 2a8e21c7

qapi-schema.json

+4 −2
Original line number Diff line number Diff line
@@ -2614,7 +2614,9 @@ 
#

# @host: host part of the address

#

# @port: port part of the address, or lowest port if @to is present

# @port: port part of the address, or lowest port if @to is present.

#        Kernel selects a free port if omitted for listener addresses.

#        #optional

#

# @to: highest port to try

#
@@ -2629,7 +2631,7 @@ 
{ 'struct': 'InetSocketAddress',

  'data': {

    'host': 'str',

    'port': 'str',

    '*port': 'str',

    '*to': 'uint16',

    '*ipv4': 'bool',

    '*ipv6': 'bool' } }

util/qemu-sockets.c

+13 −5
Original line number Diff line number Diff line
@@ -128,12 +128,15 @@ int inet_listen_opts(QemuOpts *opts, int port_offset, Error **errp) 
    ai.ai_family = PF_UNSPEC;

    ai.ai_socktype = SOCK_STREAM;



    if ((qemu_opt_get(opts, "host") == NULL) ||

        (qemu_opt_get(opts, "port") == NULL)) {

        error_setg(errp, "host and/or port not specified");

    if ((qemu_opt_get(opts, "host") == NULL)) {

        error_setg(errp, "host not specified");

        return -1;

    }

    if (qemu_opt_get(opts, "port") != NULL) {

        pstrcpy(port, sizeof(port), qemu_opt_get(opts, "port"));

    } else {

        port[0] = '\0';

    }

    addr = qemu_opt_get(opts, "host");



    to = qemu_opt_get_number(opts, "to", 0);
@@ -145,6 +148,10 @@ int inet_listen_opts(QemuOpts *opts, int port_offset, Error **errp) 
    /* lookup */

    if (port_offset) {

        unsigned long long baseport;

        if (strlen(port) == 0) {

            error_setg(errp, "port not specified");

            return -1;

        }

        if (parse_uint_full(port, &baseport, 10) < 0) {

            error_setg(errp, "can't convert to a number: %s", port);

            return -1;
@@ -156,7 +163,8 @@ int inet_listen_opts(QemuOpts *opts, int port_offset, Error **errp) 
        }

        snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);

    }

    rc = getaddrinfo(strlen(addr) ? addr : NULL, port, &ai, &res);

    rc = getaddrinfo(strlen(addr) ? addr : NULL,

                     strlen(port) ? port : NULL, &ai, &res);

    if (rc != 0) {

        error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,

                   gai_strerror(rc));