From ebbb0348dc3ad57f6be8208a90f3c2fd9fe2cbf7 Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Tue, 26 Jun 2018 13:20:54 -0400
Subject: [PATCH] Finish renaming digestset_contains to
 digestset_probably_contains

Since bloom filters are probabilistic, it's nice to make it clear
that the "contains" operation can have false positives.
---
 src/lib/crypt_ops/digestset.h |  3 ---
 src/or/entrynodes.c           |  2 +-
 src/or/routerlist.c           |  7 ++++---
 src/test/bench.c              | 10 ++++++----
 src/test/test_containers.c    |  6 +++---
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/lib/crypt_ops/digestset.h b/src/lib/crypt_ops/digestset.h
index 3b5d62c310..328979ae0d 100644
--- a/src/lib/crypt_ops/digestset.h
+++ b/src/lib/crypt_ops/digestset.h
@@ -26,7 +26,4 @@ void digestset_add(digestset_t *set, const char *addr);
 int digestset_probably_contains(const digestset_t *set,
                                 const char *addr);
 
-// XXXX to remove.
-#define digestset_contains digestset_probably_contains
-
 #endif
diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c
index 9d27d80a84..47e689b5cb 100644
--- a/src/or/entrynodes.c
+++ b/src/or/entrynodes.c
@@ -1065,7 +1065,7 @@ get_eligible_guards(const or_options_t *options,
           continue;
       }
       ++n_guards;
-      if (digestset_contains(sampled_guard_ids, node->identity))
+      if (digestset_probably_contains(sampled_guard_ids, node->identity))
         continue;
       smartlist_add(eligible_guards, (node_t*)node);
     } SMARTLIST_FOREACH_END(node);
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index a7dda68a56..66967f13f5 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -4116,7 +4116,8 @@ routerlist_remove_old_cached_routers_with_id(time_t now,
     signed_descriptor_t *r_next;
     lifespans[i-lo].idx = i;
     if (r->last_listed_as_valid_until >= now ||
-        (retain && digestset_contains(retain, r->signed_descriptor_digest))) {
+        (retain && digestset_probably_contains(retain,
+                                               r->signed_descriptor_digest))) {
       must_keep[i-lo] = 1;
     }
     if (i < hi) {
@@ -4211,7 +4212,7 @@ routerlist_remove_old_routers(void)
       router = smartlist_get(routerlist->routers, i);
       if (router->cache_info.published_on <= cutoff &&
           router->cache_info.last_listed_as_valid_until < now &&
-          !digestset_contains(retain,
+          !digestset_probably_contains(retain,
                           router->cache_info.signed_descriptor_digest)) {
         /* Too old: remove it.  (If we're a cache, just move it into
          * old_routers.) */
@@ -4232,7 +4233,7 @@ routerlist_remove_old_routers(void)
     sd = smartlist_get(routerlist->old_routers, i);
     if (sd->published_on <= cutoff &&
         sd->last_listed_as_valid_until < now &&
-        !digestset_contains(retain, sd->signed_descriptor_digest)) {
+        !digestset_probably_contains(retain, sd->signed_descriptor_digest)) {
       /* Too old.  Remove it. */
       routerlist_remove_old(routerlist, sd, i--);
     }
diff --git a/src/test/bench.c b/src/test/bench.c
index aa4af703f5..6653f4942f 100644
--- a/src/test/bench.c
+++ b/src/test/bench.c
@@ -404,18 +404,20 @@ bench_dmap(void)
          NANOCOUNT(pt3, pt4, iters*elts));
 
   for (i = 0; i < iters; ++i) {
-    SMARTLIST_FOREACH(sl, const char *, cp, n += digestset_contains(ds, cp));
-    SMARTLIST_FOREACH(sl2, const char *, cp, n += digestset_contains(ds, cp));
+    SMARTLIST_FOREACH(sl, const char *, cp,
+                      n += digestset_probably_contains(ds, cp));
+    SMARTLIST_FOREACH(sl2, const char *, cp,
+                      n += digestset_probably_contains(ds, cp));
   }
   end = perftime();
-  printf("digestset_contains: %.2f ns per element.\n",
+  printf("digestset_probably_contains: %.2f ns per element.\n",
          NANOCOUNT(pt4, end, iters*elts*2));
   /* We need to use this, or else the whole loop gets optimized out. */
   printf("Hits == %d\n", n);
 
   for (i = 0; i < fpostests; ++i) {
     crypto_rand(d, 20);
-    if (digestset_contains(ds, d)) ++fp;
+    if (digestset_probably_contains(ds, d)) ++fp;
   }
   printf("False positive rate on digestset: %.2f%%\n",
          (fp/(double)fpostests)*100);
diff --git a/src/test/test_containers.c b/src/test/test_containers.c
index acb7543b39..5c712a9b16 100644
--- a/src/test/test_containers.c
+++ b/src/test/test_containers.c
@@ -644,18 +644,18 @@ test_container_digestset(void *arg)
   }
   set = digestset_new(1000);
   SMARTLIST_FOREACH(included, const char *, cp,
-                    if (digestset_contains(set, cp))
+                    if (digestset_probably_contains(set, cp))
                       ok = 0);
   tt_assert(ok);
   SMARTLIST_FOREACH(included, const char *, cp,
                     digestset_add(set, cp));
   SMARTLIST_FOREACH(included, const char *, cp,
-                    if (!digestset_contains(set, cp))
+                    if (!digestset_probably_contains(set, cp))
                       ok = 0);
   tt_assert(ok);
   for (i = 0; i < 1000; ++i) {
     crypto_rand(d, DIGEST_LEN);
-    if (digestset_contains(set, d))
+    if (digestset_probably_contains(set, d))
       ++false_positives;
   }
   tt_int_op(50, OP_GT, false_positives); /* Should be far lower. */