Fix backup-quorum-size and use it.

1 files changed, 10 insertions, 3 deletions

diff --git a/tools/merge_sth.py b/tools/merge_sth.py
index 68b52a0..bd49c9f 100755
--- a/tools/merge_sth.py
+++ b/tools/merge_sth.py
@@ -8,7 +8,7 @@ import sys
 import json
 import urllib2
 import time
-from base64 import b64encode, b64decode
+from base64 import b64encode
 from mergetools import parse_args, get_nfetched, hexencode, hexdecode, \
      get_logorder, get_sth
 from certtools import create_ssl_context, get_public_key_from_file, \
@@ -26,13 +26,15 @@ def merge_sth(args, config, localconfig):
     mergedb = paths["mergedb"]
     sthfile = mergedb + "/sth"
     logorderfile = mergedb + "/logorder"
+    currentsizefile = mergedb + "/fetched"
     logpublickey = get_public_key_from_file(paths["logpublickey"])
-    backupquorum = localconfig.get("backupquorum", 0)
+    backupquorum = config.get("backup-quorum-size", 0)
     assert backupquorum <= len(mergenodes) - 1
     create_ssl_context(cafile=paths["https_cacertfile"])
     timing = timing_point()
 
-    trees = [{'tree_size': 0, 'sha256_root_hash': ''}]
+    trees = [{'tree_size': get_nfetched(currentsizefile, logorderfile),
+              'sha256_root_hash': ''}]
     for mergenode in mergenodes:
         if mergenode["name"] == config["primarymergenode"]:
             continue
@@ -44,6 +46,11 @@ def merge_sth(args, config, localconfig):
         trees.append(tree)
     trees.sort(key=lambda e: e['tree_size'], reverse=True)
     print >>sys.stderr, "DEBUG: trees:", trees
+
+    if backupquorum > len(trees) - 1:
+        print >>sys.stderr, "backup quorum > number of secondaries:", \
+          backupquorum, ">", len(trees) - 1
+        return
     tree_size = trees[backupquorum]['tree_size']
     root_hash = hexdecode(trees[backupquorum]['sha256_root_hash'])
     print >>sys.stderr, "DEBUG: tree size candidate at backupquorum", \