Implement host-based deletion for the hostname resolution cache.

net/dns/host_cache.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/dns/host_cache.h"
 
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 180 matching lines @@
 void HostCache::OnNetworkChange() {
   ++network_changes_;
 }
 
 void HostCache::clear() {
   DCHECK(CalledOnValidThread());
   RecordEraseAll(ERASE_CLEAR, base::TimeTicks::Now());
   entries_.clear();
 }
 
+void HostCache::ClearForHosts(
+    const base::Callback<bool(const std::string&)>& host_filter) {
+  DCHECK(CalledOnValidThread());
+
+  if (host_filter.is_null()) {
+    clear();
+    return;
+  }
+
+  base::TimeTicks now = base::TimeTicks::Now();
+  for (EntryMap::iterator it = entries_.begin(); it != entries_.end();) {
+    EntryMap::iterator next_it = std::next(it);
+
+    if (host_filter.Run(it->first.hostname)) {
+      RecordErase(ERASE_CLEAR, now, it->second);
+      entries_.erase(it);
+    }
+
+    it = next_it;
+  }
+}
+
 size_t HostCache::size() const {
   DCHECK(CalledOnValidThread());
   return entries_.size();
 }
 
 size_t HostCache::max_entries() const {
   DCHECK(CalledOnValidThread());
   return max_entries_;
 }
 
@@ skipping 124 matching lines @@
     CACHE_HISTOGRAM_TIME("EraseValid.ValidFor", -stale.expired_by);
   }
 }
 
 void HostCache::RecordEraseAll(EraseReason reason, base::TimeTicks now) {
   for (const auto& it : entries_)
     RecordErase(reason, now, it.second);
 }
 
 }  // namespace net