qdev: remove baked in notion of aliases (v2)
[qemu.git] / migration-exec.c
1 /*
2 * QEMU live migration
3 *
4 * Copyright IBM, Corp. 2008
5 * Copyright Dell MessageOne 2008
6 *
7 * Authors:
8 * Anthony Liguori <aliguori@us.ibm.com>
9 * Charles Duffy <charles_duffy@messageone.com>
10 *
11 * This work is licensed under the terms of the GNU GPL, version 2. See
12 * the COPYING file in the top-level directory.
13 *
14 * Contributions after 2012-01-13 are licensed under the terms of the
15 * GNU GPL, version 2 or (at your option) any later version.
16 */
17
18 #include "qemu-common.h"
19 #include "qemu_socket.h"
20 #include "migration.h"
21 #include "qemu-char.h"
22 #include "buffered_file.h"
23 #include "block.h"
24 #include <sys/types.h>
25 #include <sys/wait.h>
26
27 //#define DEBUG_MIGRATION_EXEC
28
29 #ifdef DEBUG_MIGRATION_EXEC
30 #define DPRINTF(fmt, ...) \
31 do { printf("migration-exec: " fmt, ## __VA_ARGS__); } while (0)
32 #else
33 #define DPRINTF(fmt, ...) \
34 do { } while (0)
35 #endif
36
37 static int file_errno(MigrationState *s)
38 {
39 return errno;
40 }
41
42 static int file_write(MigrationState *s, const void * buf, size_t size)
43 {
44 return write(s->fd, buf, size);
45 }
46
47 static int exec_close(MigrationState *s)
48 {
49 int ret = 0;
50 DPRINTF("exec_close\n");
51 if (s->opaque) {
52 ret = qemu_fclose(s->opaque);
53 s->opaque = NULL;
54 s->fd = -1;
55 if (ret >= 0 && !(WIFEXITED(ret) && WEXITSTATUS(ret) == 0)) {
56 /* close succeeded, but non-zero exit code: */
57 ret = -EIO; /* fake errno value */
58 }
59 }
60 return ret;
61 }
62
63 int exec_start_outgoing_migration(MigrationState *s, const char *command)
64 {
65 FILE *f;
66
67 f = popen(command, "w");
68 if (f == NULL) {
69 DPRINTF("Unable to popen exec target\n");
70 goto err_after_popen;
71 }
72
73 s->fd = fileno(f);
74 if (s->fd == -1) {
75 DPRINTF("Unable to retrieve file descriptor for popen'd handle\n");
76 goto err_after_open;
77 }
78
79 socket_set_nonblock(s->fd);
80
81 s->opaque = qemu_popen(f, "w");
82
83 s->close = exec_close;
84 s->get_error = file_errno;
85 s->write = file_write;
86
87 migrate_fd_connect(s);
88 return 0;
89
90 err_after_open:
91 pclose(f);
92 err_after_popen:
93 return -1;
94 }
95
96 static void exec_accept_incoming_migration(void *opaque)
97 {
98 QEMUFile *f = opaque;
99
100 process_incoming_migration(f);
101 qemu_set_fd_handler2(qemu_stdio_fd(f), NULL, NULL, NULL, NULL);
102 qemu_fclose(f);
103 }
104
105 int exec_start_incoming_migration(const char *command)
106 {
107 QEMUFile *f;
108
109 DPRINTF("Attempting to start an incoming migration\n");
110 f = qemu_popen_cmd(command, "r");
111 if(f == NULL) {
112 DPRINTF("Unable to apply qemu wrapper to popen file\n");
113 return -errno;
114 }
115
116 qemu_set_fd_handler2(qemu_stdio_fd(f), NULL,
117 exec_accept_incoming_migration, NULL, f);
118
119 return 0;
120 }