ABANDONED Handle multiple AlternateProtocols for each HostPortPair.

net/http/http_server_properties_impl.cc

Index: net/http/http_server_properties_impl.cc
diff --git a/net/http/http_server_properties_impl.cc b/net/http/http_server_properties_impl.cc
index a8bc04a685980d1f5adb6d1ec778cdbc58f77968..75f66250acc4edb4de6366ab56bd9186b2344df8 100644
--- a/net/http/http_server_properties_impl.cc
+++ b/net/http/http_server_properties_impl.cc
@@ -50,13 +50,22 @@ void HttpServerPropertiesImpl::InitializeSpdyServers(
 
 void HttpServerPropertiesImpl::InitializeAlternateProtocolServers(
     AlternateProtocolMap* alternate_protocol_map) {
-  // Keep all the broken ones since those don't get persisted.
-  for (AlternateProtocolMap::iterator it = alternate_protocol_map_.begin();
-       it != alternate_protocol_map_.end();) {
-    AlternateProtocolMap::iterator old_it = it;
-    ++it;
-    if (!old_it->second.is_broken) {
-      alternate_protocol_map_.Erase(old_it);
+  for (AlternateProtocolMap::iterator alternate_protocols =
+           alternate_protocol_map_.begin();
+       alternate_protocols != alternate_protocol_map_.end();) {
+    // Keep all the broken ones since those don't get persisted.
+    for (AlternateProtocols::iterator it = alternate_protocols->second.begin();
+         it != alternate_protocols->second.end();) {
+      if (!it->is_broken) {
+        it = alternate_protocols->second.erase(it);
+      } else {
+        ++it;
+      }
+    }
+    if (alternate_protocols->second.size() == 0) {
+      alternate_protocols = alternate_protocol_map_.Erase(alternate_protocols);
+    } else {
+      ++alternate_protocols;
     }
   }
 
@@ -137,21 +146,20 @@ void HttpServerPropertiesImpl::GetSpdyServerList(
   }
 }
 
-static const AlternateProtocolInfo* g_forced_alternate_protocol = NULL;
+static AlternateProtocols* g_forced_alternate_protocol =
+    new AlternateProtocols();
 
 // static
 void HttpServerPropertiesImpl::ForceAlternateProtocol(
     const AlternateProtocolInfo& info) {
+  DisableForcedAlternateProtocol();
   // Note: we're going to leak this.
-  if (g_forced_alternate_protocol)
-    delete g_forced_alternate_protocol;
-  g_forced_alternate_protocol = new AlternateProtocolInfo(info);
+  g_forced_alternate_protocol->push_back(info);
 }
 
 // static
 void HttpServerPropertiesImpl::DisableForcedAlternateProtocol() {
-  delete g_forced_alternate_protocol;
-  g_forced_alternate_protocol = NULL;
+  g_forced_alternate_protocol->clear();
 }
 
 base::WeakPtr<HttpServerProperties> HttpServerPropertiesImpl::GetWeakPtr() {
@@ -225,11 +233,21 @@ void HttpServerPropertiesImpl::MaybeForceHTTP11(const HostPortPair& server,
 
 bool HttpServerPropertiesImpl::HasAlternateProtocol(
     const HostPortPair& server) {
-  if (g_forced_alternate_protocol)
+  if (!g_forced_alternate_protocol->empty())
     return true;
-  AlternateProtocolMap::const_iterator it = alternate_protocol_map_.Get(server);
-  if (it != alternate_protocol_map_.end())
-    return it->second.probability >= alternate_protocol_probability_threshold_;
+  AlternateProtocolMap::const_iterator alternate_protocols =
+      alternate_protocol_map_.Get(server);
+  if (alternate_protocols != alternate_protocol_map_.end()) {
+    for (AlternateProtocols::const_iterator alternate_protocol =
+             alternate_protocols->second.begin();
+         alternate_protocol != alternate_protocols->second.end();
+         alternate_protocol++) {
+      if (alternate_protocol->probability >=
+          alternate_protocol_probability_threshold_) {
+        return true;
+      }
+    }
+  }
 
   auto canonical = GetCanonicalHost(server);
   if (canonical == canonical_host_to_origin_map_.end() ||
@@ -253,8 +271,7 @@ std::string HttpServerPropertiesImpl::GetCanonicalSuffix(
   return std::string();
 }
 
-AlternateProtocolInfo
-HttpServerPropertiesImpl::GetAlternateProtocol(
+const AlternateProtocols& HttpServerPropertiesImpl::GetAlternateProtocols(
     const HostPortPair& server) {
   DCHECK(HasAlternateProtocol(server));
 
@@ -269,39 +286,50 @@ HttpServerPropertiesImpl::GetAlternateProtocol(
     return alternate_protocol_map_.Get(canonical_host->second)->second;
 
   // We must be forcing an alternate.
-  DCHECK(g_forced_alternate_protocol);
+  DCHECK(!g_forced_alternate_protocol->empty());
   return *g_forced_alternate_protocol;
 }
 
-void HttpServerPropertiesImpl::SetAlternateProtocol(
+void HttpServerPropertiesImpl::AddAlternateProtocol(
     const HostPortPair& server,
     uint16 alternate_port,
     AlternateProtocol alternate_protocol,
     double alternate_probability) {
-
   AlternateProtocolInfo alternate(alternate_port,
                                   alternate_protocol,
                                   alternate_probability);
-  if (HasAlternateProtocol(server)) {
-    const AlternateProtocolInfo existing_alternate =
-        GetAlternateProtocol(server);
-
-    if (existing_alternate.is_broken) {
-      DVLOG(1) << "Ignore alternate protocol since it's known to be broken.";
-      return;
+  // Do not call HasAlternateProtocol(), because we don't care about
+  // |g_forced_alternate_protocol|, or whether the alternate protocol
+  // probability is higher than the threshold.
+  AlternateProtocolMap::iterator map_it = alternate_protocol_map_.Get(server);
+  if (map_it != alternate_protocol_map_.end()) {
+    AlternateProtocols existing_alternates = map_it->second;
+    AlternateProtocols::iterator it;
+    for (it = existing_alternates.begin(); it != existing_alternates.end();
+         ++it) {
+      if (it->EqualsModuloProbabilityAndProtocol(alternate)) {

[Bence, 2015/01/30 21:24:50]

This needs to be EqualsModuloProbability.  We couldn't check for protocol
equality while brokenness was encoded in that, but since
https://crrev.com/701163002, we should.

+        break;
+      }
     }
 
-    if (!existing_alternate.Equals(alternate)) {
-      LOG(WARNING) << "Changing the alternate protocol for: "
-                   << server.ToString()
-                   << " from [Port: " << existing_alternate.port
-                   << ", Protocol: " << existing_alternate.protocol
-                   << ", Probability: " << existing_alternate.probability
-                   << "] to [Port: " << alternate_port
-                   << ", Protocol: " << alternate_protocol
-                   << ", Probability: " << alternate_probability
-                   << "].";
+    if (it != existing_alternates.end()) {
+      if (it->is_broken) {
+        DVLOG(1) << "Ignore alternate protocol since it's known to be broken.";
+        return;
+      }
+      if (it->probability != alternate_probability) {
+        LOG(WARNING) << "Changing the probability of alternate protocol for: "
+                     << server.ToString() << " Port: " << it->port
+                     << ", Protocol: " << it->protocol
+                     << ", Probability from: " << it->probability
+                     << " to: " << alternate_probability << ".";
+        it->probability = alternate_probability;
+      }
+    } else {
+      existing_alternates.push_back(alternate);
     }
+
+    alternate_protocol_map_.Put(server, existing_alternates);
   } else {
     if (alternate_probability >= alternate_protocol_probability_threshold_) {
       // TODO(rch): Consider the case where multiple requests are started
@@ -309,10 +337,10 @@ void HttpServerPropertiesImpl::SetAlternateProtocol(
       // would reach this code, whereas all of them should should have.
       HistogramAlternateProtocolUsage(ALTERNATE_PROTOCOL_USAGE_MAPPING_MISSING);
     }
+    alternate_protocol_map_.Put(server,
+                                AlternateProtocols(/*size=*/1, alternate));
   }
 
-  alternate_protocol_map_.Put(server, alternate);
-
   // If this host ends with a canonical suffix, then set it as the
   // canonical host.
   for (size_t i = 0; i < canonical_suffixes_.size(); ++i) {
@@ -326,19 +354,24 @@ void HttpServerPropertiesImpl::SetAlternateProtocol(
 }
 
 void HttpServerPropertiesImpl::SetBrokenAlternateProtocol(
-    const HostPortPair& server) {
-  AlternateProtocolMap::iterator it = alternate_protocol_map_.Get(server);
-  if (it == alternate_protocol_map_.end()) {
-    if (!HasAlternateProtocol(server)) {
-      LOG(DFATAL) << "Trying to mark unknown alternate protocol broken.";
-      return;
+    const HostPortPair& server,
+    const AlternateProtocolInfo& broken_alternate_protocol) {
+  AddAlternateProtocol(server, broken_alternate_protocol.port,
+                       broken_alternate_protocol.protocol,
+                       broken_alternate_protocol.probability);
+  AlternateProtocolMap::iterator alternate_protocols =
+      alternate_protocol_map_.Get(server);
+  DCHECK(alternate_protocols != alternate_protocol_map_.end());
+  AlternateProtocols::iterator it;
+  for (it = alternate_protocols->second.begin();
+       it != alternate_protocols->second.end(); ++it) {
+    if (it->Equals(broken_alternate_protocol)) {
+      it->is_broken = true;
+      break;
     }
-    // This server's alternate protocol information is coming from a canonical
-    // server. Add an entry in the map for this server explicitly so that
-    // it can be marked as broken.
-    it = alternate_protocol_map_.Put(server, GetAlternateProtocol(server));
   }
-  it->second.is_broken = true;
+  DCHECK(it != alternate_protocols->second.end());
+
   int count = ++broken_alternate_protocol_map_[server];
   base::TimeDelta delay =
       base::TimeDelta::FromSeconds(kBrokenAlternateProtocolDelaySecs);
@@ -352,20 +385,21 @@ void HttpServerPropertiesImpl::SetBrokenAlternateProtocol(
   RemoveCanonicalHost(server);
 
   // If this is the only entry in the list, schedule an expiration task.
-  // Otherwse it will be rescheduled automatically when the pending
-  // task runs.
+  // Otherwise it will be rescheduled automatically when the pending task runs.
   if (broken_alternate_protocol_list_.size() == 1) {
     ScheduleBrokenAlternateProtocolMappingsExpiration();
   }
 }
 
 bool HttpServerPropertiesImpl::WasAlternateProtocolRecentlyBroken(
-    const HostPortPair& server) {
+    const HostPortPair& server,
+    const AlternateProtocolInfo& alternate_protocol) {
   return ContainsKey(broken_alternate_protocol_map_, server);
 }
 
 void HttpServerPropertiesImpl::ConfirmAlternateProtocol(
-    const HostPortPair& server) {
+    const HostPortPair& server,
+    const AlternateProtocolInfo& alternate_protocol) {
   broken_alternate_protocol_map_.erase(server);
 }
 
@@ -378,6 +412,47 @@ void HttpServerPropertiesImpl::ClearAlternateProtocol(
   RemoveCanonicalHost(server);
 }
 
+void HttpServerPropertiesImpl::ClearNonBrokenAlternateProtocols(
+    const HostPortPair& server) {
+  AlternateProtocolMap::iterator alternate_protocols =
+      alternate_protocol_map_.Peek(server);
+  if (alternate_protocols != alternate_protocol_map_.end()) {
+    for (AlternateProtocols::iterator it = alternate_protocols->second.begin();
+         it != alternate_protocols->second.end();) {
+      if (!it->is_broken) {
+        it = alternate_protocols->second.erase(it);
+      } else {
+        ++it;
+      }
+    }
+    if (alternate_protocols->second.size() == 0) {
+      alternate_protocols = alternate_protocol_map_.Erase(alternate_protocols);
+      RemoveCanonicalHost(server);
+    }
+  }
+}
+
+void HttpServerPropertiesImpl::RemoveAlternateProtocol(
+    const HostPortPair& server,
+    const AlternateProtocolInfo& alternate_protocol) {
+  AlternateProtocolMap::iterator alternate_protocols =
+      alternate_protocol_map_.Peek(server);
+  if (alternate_protocols == alternate_protocol_map_.end()) {
+    return;
+  }
+  for (AlternateProtocols::iterator it = alternate_protocols->second.begin();
+       it != alternate_protocols->second.end(); ++it) {
+    if (it->Equals(alternate_protocol)) {
+      alternate_protocols->second.erase(it);
+      break;
+    }
+  }
+  if (alternate_protocols->second.size() == 0) {
+    alternate_protocol_map_.Erase(alternate_protocols);
+    RemoveCanonicalHost(server);
+  }
+}
+
 const AlternateProtocolMap&
 HttpServerPropertiesImpl::alternate_protocol_map() const {
   return alternate_protocol_map_;