virtio-serial: avoid crash when port has no name
[qemu.git] / migration-unix.c
1 /*
2 * QEMU live migration via Unix Domain Sockets
3 *
4 * Copyright Red Hat, Inc. 2009
5 *
6 * Authors:
7 * Chris Lalancette <clalance@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
14 */
15
16 #include <string.h>
17
18 #include "qemu-common.h"
19 #include "qemu/error-report.h"
20 #include "qemu/sockets.h"
21 #include "qemu/main-loop.h"
22 #include "migration/migration.h"
23 #include "migration/qemu-file.h"
24 #include "block/block.h"
25
26 //#define DEBUG_MIGRATION_UNIX
27
28 #ifdef DEBUG_MIGRATION_UNIX
29 #define DPRINTF(fmt, ...) \
30 do { printf("migration-unix: " fmt, ## __VA_ARGS__); } while (0)
31 #else
32 #define DPRINTF(fmt, ...) \
33 do { } while (0)
34 #endif
35
36 static void unix_wait_for_connect(int fd, Error *err, void *opaque)
37 {
38 MigrationState *s = opaque;
39
40 if (fd < 0) {
41 DPRINTF("migrate connect error: %s\n", error_get_pretty(err));
42 s->file = NULL;
43 migrate_fd_error(s);
44 } else {
45 DPRINTF("migrate connect success\n");
46 s->file = qemu_fopen_socket(fd, "wb");
47 migrate_fd_connect(s);
48 }
49 }
50
51 void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp)
52 {
53 unix_nonblocking_connect(path, unix_wait_for_connect, s, errp);
54 }
55
56 static void unix_accept_incoming_migration(void *opaque)
57 {
58 struct sockaddr_un addr;
59 socklen_t addrlen = sizeof(addr);
60 int s = (intptr_t)opaque;
61 QEMUFile *f;
62 int c, err;
63
64 do {
65 c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
66 err = errno;
67 } while (c < 0 && err == EINTR);
68 qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
69 close(s);
70
71 DPRINTF("accepted migration\n");
72
73 if (c < 0) {
74 error_report("could not accept migration connection (%s)",
75 strerror(err));
76 return;
77 }
78
79 f = qemu_fopen_socket(c, "rb");
80 if (f == NULL) {
81 error_report("could not qemu_fopen socket");
82 goto out;
83 }
84
85 process_incoming_migration(f);
86 return;
87
88 out:
89 close(c);
90 }
91
92 void unix_start_incoming_migration(const char *path, Error **errp)
93 {
94 int s;
95
96 s = unix_listen(path, NULL, 0, errp);
97 if (s < 0) {
98 return;
99 }
100
101 qemu_set_fd_handler2(s, NULL, unix_accept_incoming_migration, NULL,
102 (void *)(intptr_t)s);
103 }