[PATCH v10 27/31] COLO proxy: preresume, postresume and checkpoint

[Wen Congyang <wency@cn.fujitsu.com>]

preresume, postresume and checkpoint

Signed-off-by: Yang Hongyang <hongyang.yang@easystack.cn>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
---
 tools/libxl/libxl_colo.h       |  4 +++
 tools/libxl/libxl_colo_proxy.c | 62 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)

diff --git a/tools/libxl/libxl_colo.h b/tools/libxl/libxl_colo.h
index 6d8cd4f..17dd07f 100644
--- a/tools/libxl/libxl_colo.h
+++ b/tools/libxl/libxl_colo.h
@@ -29,4 +29,8 @@ extern void libxl__colo_save_teardown(libxl__egc *egc,
 
 extern int colo_proxy_setup(libxl__colo_proxy_state *cps);
 extern void colo_proxy_teardown(libxl__colo_proxy_state *cps);
+extern void colo_proxy_preresume(libxl__colo_proxy_state *cps);
+extern void colo_proxy_postresume(libxl__colo_proxy_state *cps);
+extern int colo_proxy_checkpoint(libxl__colo_proxy_state *cps,
+                                 unsigned int timeout_us);
 #endif
diff --git a/tools/libxl/libxl_colo_proxy.c b/tools/libxl/libxl_colo_proxy.c
index e07e640..c714b52 100644
--- a/tools/libxl/libxl_colo_proxy.c
+++ b/tools/libxl/libxl_colo_proxy.c
@@ -228,3 +228,65 @@ void colo_proxy_teardown(libxl__colo_proxy_state *cps)
         cps->sock_fd = -1;
     }
 }
+
+/* ========= colo-proxy: preresume, postresume and checkpoint ========== */
+
+void colo_proxy_preresume(libxl__colo_proxy_state *cps)
+{
+    colo_proxy_send(cps, NULL, 0, COLO_CHECKPOINT);
+    /* TODO: need to handle if the call fails... */
+}
+
+void colo_proxy_postresume(libxl__colo_proxy_state *cps)
+{
+    /* nothing to do... */
+}
+
+typedef struct colo_msg {
+    bool is_checkpoint;
+} colo_msg;
+
+/*
+ * Return value:
+ * -1: error
+ *  0: no checkpoint event is received before timeout
+ *  1: do checkpoint
+ */
+int colo_proxy_checkpoint(libxl__colo_proxy_state *cps,
+                          unsigned int timeout_us)
+{
+    uint8_t *buff;
+    int64_t size;
+    struct nlmsghdr *h;
+    struct colo_msg *m;
+    int ret = -1;
+
+    STATE_AO_GC(cps->ao);
+
+    size = colo_proxy_recv(cps, &buff, timeout_us);
+
+    /* timeout, return no checkpoint message. */
+    if (size <= 0) {
+        return 0;
+    }
+
+    h = (struct nlmsghdr *) buff;
+
+    if (h->nlmsg_type == NLMSG_ERROR) {
+        LOG(ERROR, "receive NLMSG_ERROR");
+        goto out;
+    }
+
+    if (h->nlmsg_len < NLMSG_LENGTH(sizeof(*m))) {
+        LOG(ERROR, "NLMSG_LENGTH is too short");
+        goto out;
+    }
+
+    m = NLMSG_DATA(h);
+
+    ret = m->is_checkpoint ? 1 : 0;
+
+out:
+    free(buff);
+    return ret;
+}
-- 
2.5.0