migration/exec.c

   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 }