xref: /qemu/migration/exec.c (revision ec6f3fc3) 
1 /*
2  * QEMU live migration
3  *
4  * Copyright IBM, Corp. 2008
5  * Copyright Dell MessageOne 2008
6  * Copyright Red Hat, Inc. 2015-2016
7  *
8  * Authors:
9  *  Anthony Liguori   <aliguori@us.ibm.com>
10  *  Charles Duffy     <charles_duffy@messageone.com>
11  *  Daniel P. Berrange <berrange@redhat.com>
12  *
13  * This work is licensed under the terms of the GNU GPL, version 2.  See
14  * the COPYING file in the top-level directory.
15  *
16  * Contributions after 2012-01-13 are licensed under the terms of the
17  * GNU GPL, version 2 or (at your option) any later version.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/error-report.h"
22 #include "channel.h"
23 #include "exec.h"
24 #include "migration.h"
25 #include "io/channel-command.h"
26 #include "trace.h"
27 #include "qemu/cutils.h"
28 
29 #ifdef WIN32
30 const char *exec_get_cmd_path(void)
31 {
32     g_autofree char *detected_path = g_new(char, MAX_PATH);
33     if (GetSystemDirectoryA(detected_path, MAX_PATH) == 0) {
34         warn_report("Could not detect cmd.exe path, using default.");
35         return "C:\\Windows\\System32\\cmd.exe";
36     }
37     pstrcat(detected_path, MAX_PATH, "\\cmd.exe");
38     return g_steal_pointer(&detected_path);
39 }
40 #endif
41 
42 /* provides the length of strList */
43 static int
44 str_list_length(strList *list)
45 {
46     int len = 0;
47     strList *elem;
48 
49     for (elem = list; elem != NULL; elem = elem->next) {
50         len++;
51     }
52 
53     return len;
54 }
55 
56 static void
57 init_exec_array(strList *command, char **argv, Error **errp)
58 {
59     int i = 0;
60     strList *lst;
61 
62     for (lst = command; lst; lst = lst->next) {
63         argv[i++] = lst->value;
64     }
65 
66     argv[i] = NULL;
67     return;
68 }
69 
70 void exec_start_outgoing_migration(MigrationState *s, strList *command,
71                                    Error **errp)
72 {
73     QIOChannel *ioc;
74 
75     int length = str_list_length(command);
76     g_auto(GStrv) argv = (char **) g_new0(const char *, length + 1);
77 
78     init_exec_array(command, argv, errp);
79     g_autofree char *new_command = g_strjoinv(" ", (char **)argv);
80 
81     trace_migration_exec_outgoing(new_command);
82     ioc = QIO_CHANNEL(
83         qio_channel_command_new_spawn(
84                             (const char * const *) g_steal_pointer(&argv),
85                             O_RDWR,
86                             errp));
87     if (!ioc) {
88         return;
89     }
90 
91     qio_channel_set_name(ioc, "migration-exec-outgoing");
92     migration_channel_connect(s, ioc, NULL, NULL);
93     object_unref(OBJECT(ioc));
94 }
95 
96 static gboolean exec_accept_incoming_migration(QIOChannel *ioc,
97                                                GIOCondition condition,
98                                                gpointer opaque)
99 {
100     migration_channel_process_incoming(ioc);
101     object_unref(OBJECT(ioc));
102     return G_SOURCE_REMOVE;
103 }
104 
105 void exec_start_incoming_migration(strList *command, Error **errp)
106 {
107     QIOChannel *ioc;
108 
109     int length = str_list_length(command);
110     g_auto(GStrv) argv = (char **) g_new0(const char *, length + 1);
111 
112     init_exec_array(command, argv, errp);
113     g_autofree char *new_command = g_strjoinv(" ", (char **)argv);
114 
115     trace_migration_exec_incoming(new_command);
116     ioc = QIO_CHANNEL(
117         qio_channel_command_new_spawn(
118                             (const char * const *) g_steal_pointer(&argv),
119                             O_RDWR,
120                             errp));
121     if (!ioc) {
122         return;
123     }
124 
125     qio_channel_set_name(ioc, "migration-exec-incoming");
126     qio_channel_add_watch_full(ioc, G_IO_IN,
127                                exec_accept_incoming_migration,
128                                NULL, NULL,
129                                g_main_context_get_thread_default());
130 }
131