migration: convert migration 'uri' into 'MigrateAddress'

This patch parses 'migrate' and 'migrate-incoming' QAPI's 'uri'
string containing migration connection related information
and stores them inside well defined 'MigrateAddress' struct.

Fabiano fixed for "file" transport.

Suggested-by: Aravind Retnakaran <aravind.retnakaran@nutanix.com>
Signed-off-by: Het Gala <het.gala@nutanix.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231023182053.8711-4-farosas@suse.de>
Message-ID: <20231023182053.8711-5-farosas@suse.de>

migration/exec.c

@@ -27,7 +27,6 @@
 #include "qemu/cutils.h"
 
 #ifdef WIN32
-const char *exec_get_cmd_path(void);
 const char *exec_get_cmd_path(void)
 {
     g_autofree char *detected_path = g_new(char, MAX_PATH);

migration/exec.h

@@ -19,6 +19,10 @@
 
 #ifndef QEMU_MIGRATION_EXEC_H
 #define QEMU_MIGRATION_EXEC_H
+
+#ifdef WIN32
+const char *exec_get_cmd_path(void);
+#endif
 void exec_start_incoming_migration(const char *host_port, Error **errp);
 
 void exec_start_outgoing_migration(MigrationState *s, const char *host_port,

migration/file.c

@@ -19,7 +19,7 @@
 
 /* Remove the offset option from @filespec and return it in @offsetp. */
 
-static int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp)
+int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp)
 {
     char *option = strstr(filespec, OFFSET_OPTION);
     int ret;

migration/file.h

@@ -11,4 +11,5 @@ void file_start_incoming_migration(const char *filename, Error **errp);
 
 void file_start_outgoing_migration(MigrationState *s, const char *filename,
                                    Error **errp);
+int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp);
 #endif

migration/migration.c

@@ -66,6 +66,7 @@
 #include "sysemu/qtest.h"
 #include "options.h"
 #include "sysemu/dirtylimit.h"
+#include "qemu/sockets.h"
 
 static NotifierList migration_state_notifiers =
     NOTIFIER_LIST_INITIALIZER(migration_state_notifiers);
@@ -453,9 +454,62 @@ void migrate_add_address(SocketAddress *address)
                       QAPI_CLONE(SocketAddress, address));
 }
 
+static bool migrate_uri_parse(const char *uri,
+                              MigrationAddress **channel,
+                              Error **errp)
+{
+    g_autoptr(MigrationAddress) addr = g_new0(MigrationAddress, 1);
+    SocketAddress *saddr = NULL;
+    InetSocketAddress *isock = &addr->u.rdma;
+    strList **tail = &addr->u.exec.args;
+
+    if (strstart(uri, "exec:", NULL)) {
+        addr->transport = MIGRATION_ADDRESS_TYPE_EXEC;
+#ifdef WIN32
+        QAPI_LIST_APPEND(tail, g_strdup(exec_get_cmd_path()));
+        QAPI_LIST_APPEND(tail, g_strdup("/c"));
+#else
+        QAPI_LIST_APPEND(tail, g_strdup("/bin/sh"));
+        QAPI_LIST_APPEND(tail, g_strdup("-c"));
+#endif
+        QAPI_LIST_APPEND(tail, g_strdup(uri + strlen("exec:")));
+    } else if (strstart(uri, "rdma:", NULL)) {
+        if (inet_parse(isock, uri + strlen("rdma:"), errp)) {
+            qapi_free_InetSocketAddress(isock);
+            return false;
+        }
+        addr->transport = MIGRATION_ADDRESS_TYPE_RDMA;
+    } else if (strstart(uri, "tcp:", NULL) ||
+                strstart(uri, "unix:", NULL) ||
+                strstart(uri, "vsock:", NULL) ||
+                strstart(uri, "fd:", NULL)) {
+        addr->transport = MIGRATION_ADDRESS_TYPE_SOCKET;
+        saddr = socket_parse(uri, errp);
+        if (!saddr) {
+            return false;
+        }
+        addr->u.socket.type = saddr->type;
+        addr->u.socket.u = saddr->u;
+    } else if (strstart(uri, "file:", NULL)) {
+        addr->transport = MIGRATION_ADDRESS_TYPE_FILE;
+        addr->u.file.filename = g_strdup(uri + strlen("file:"));
+        if (file_parse_offset(addr->u.file.filename, &addr->u.file.offset,
+                              errp)) {
+            return false;
+        }
+    } else {
+        error_setg(errp, "unknown migration protocol: %s", uri);
+        return false;
+    }
+
+    *channel = g_steal_pointer(&addr);
+    return true;
+}
+
 static void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p = NULL;
+    g_autoptr(MigrationAddress) channel = NULL;
     MigrationIncomingState *mis = migration_incoming_get_current();
 
     /* URI is not suitable for migration? */
@@ -463,6 +517,10 @@ static void qemu_start_incoming_migration(const char *uri, Error **errp)
         return;
     }
 
+    if (uri && !migrate_uri_parse(uri, &channel, errp)) {
+        return;
+    }
+
     migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
                       MIGRATION_STATUS_SETUP);
 
@@ -1840,12 +1898,17 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
     Error *local_err = NULL;
     MigrationState *s = migrate_get_current();
     const char *p = NULL;
+    g_autoptr(MigrationAddress) channel = NULL;
 
     /* URI is not suitable for migration? */
     if (!migration_channels_and_uri_compatible(uri, errp)) {
         return;
     }
 
+    if (!migrate_uri_parse(uri, &channel, errp)) {
+        return;
+    }
+
     resume_requested = has_resume && resume;
     if (!migrate_prepare(s, has_blk && blk, has_inc && inc,
                          resume_requested, errp)) {