geo-rep: checkpointing

- gluster vol geo-rep M S conf checkpoint <LABEL|now>

  sets a checkpoint with LABEL (the keyword "now" is special,
  it's rendered to the label "as of <timestamp of current time>")
  that's used to refer to the checkpoint in the sequel.

  (Technically, gsyncd makes a note of the xtime of master's root
  as of setting the checkpoint, called the "checkpoint target".)

- gluster vol geo-rep M S conf \!checkpoint

  deletes the checkpoint.

- gluster vol geo-rep M S stat

  if status is OK, and there is a checkpoint configured, the checkpoint
  info is appended to status (either "not yet reached", or
  "completed at <timestamp of completion>").

  (Technically, the worker runs a thread that monitors / serializes /
  verifies checkpoint status, and answers checkpoint status requests
  through a UNIX socket; monitoring boils down to querying the xtime
  of slave's root and comparing with the target.)

- gluster vol geo-rep M S conf log-file | xargs grep checkpoint

  displays the checkpoint history. Set, delete and completion events
  are logged properly.

Change-Id: I4398e0819f1504e6e496b4209e91a0e156e1a0f8
BUG: 826512
Signed-off-by: Csaba Henk <csaba@redhat.com>
Reviewed-on: http://review.gluster.com/3491
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Venky Shankar <vshankar@redhat.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index f447ccae3d5..931d89ae1bd 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -1577,6 +1577,29 @@ cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
                         }
                         append_str[append_len - 2] = '\0';
 
+                        /* "checkpoint now" is special: we resolve that "now" */
+                        if (strcmp (words[cmdi + 1], "checkpoint") == 0 &&
+                            strcmp (append_str, "now") == 0) {
+                                struct timeval tv = {0,};
+                                struct tm     *tm = NULL;
+
+                                ret = gettimeofday (&tv, NULL);
+                                if (ret == -1)
+                                         goto out;
+                                tm = localtime (&tv.tv_sec);
+
+                                GF_FREE (append_str);
+                                append_str = GF_CALLOC (1, 300, cli_mt_append_str);
+                                if (!append_str) {
+                                        ret = -1;
+                                        goto out;
+                                }
+                                strcpy (append_str, "as of ");
+                                strftime (append_str + strlen ("as of "),
+                                          300 - strlen ("as of "),
+                                          "%Y-%m-%d %H:%M:%S", tm);
+                        }
+
                         ret = dict_set_dynstr (dict, "op_value", append_str);
                 }