[SYNC] Refactor SyncSourceInfo and add support in chrome invalidation client ...

chrome/browser/sync/engine/syncer_thread.cc

Index: chrome/browser/sync/engine/syncer_thread.cc
===================================================================
--- chrome/browser/sync/engine/syncer_thread.cc	(revision 71061)
+++ chrome/browser/sync/engine/syncer_thread.cc	(working copy)
@@ -7,6 +7,8 @@
 #include <algorithm>
 #include <map>
 #include <queue>
+#include <string>
+#include <vector>
 
 #include "base/rand_util.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
@@ -54,6 +56,19 @@
 
 const int SyncerThread::kMaxBackoffSeconds = 60 * 60 * 4;  // 4 hours.
 
+void SyncerThread::NudgeSyncerWithPayloads(
+    int milliseconds_from_now,
+    NudgeSource source,
+    const std::vector<std::string>& payloads) {
+  base::AutoLock lock(lock_);
+  if (vault_.syncer_ == NULL) {
+    return;
+  }
+
+  syncable::ModelTypeBitSet model_types;  // All false by default.
+  NudgeSyncImpl(milliseconds_from_now, source, model_types, payloads);
+}
+
 void SyncerThread::NudgeSyncerWithDataTypes(
     int milliseconds_from_now,
     NudgeSource source,
@@ -63,7 +78,8 @@
     return;
   }
 
-  NudgeSyncImpl(milliseconds_from_now, source, model_types);
+  std::vector<std::string> empty_payload;
+  NudgeSyncImpl(milliseconds_from_now, source, model_types, empty_payload);
 }
 
 void SyncerThread::NudgeSyncer(
@@ -74,8 +90,10 @@
     return;
   }
 
-  syncable::ModelTypeBitSet model_types;  // All false by default.
-  NudgeSyncImpl(milliseconds_from_now, source, model_types);
+  syncable::ModelTypeBitSet model_types;
+  model_types.set();  // The default nudge acts on all datatypes.
+  std::vector<std::string> empty_payload;  // No payloads.
+  NudgeSyncImpl(milliseconds_from_now, source, model_types, empty_payload);
 }
 
 SyncerThread::SyncerThread(sessions::SyncSessionContext* context)
@@ -342,12 +360,14 @@
     // Update timing information for how often these datatypes are triggering
     // nudges.
     base::TimeTicks now = TimeTicks::Now();
-    for (size_t i = syncable::FIRST_REAL_MODEL_TYPE;
-         i < session->source().second.size();
-         ++i) {
-      if (session->source().second[i]) {
-        syncable::PostTimeToTypeHistogram(syncable::ModelType(i),
-                                          now - last_sync_time);
+    if (!last_sync_time.is_null()) {
+      for (size_t i = syncable::FIRST_REAL_MODEL_TYPE;
+           i < session->source().types().size();
+           ++i) {
+        if (session->source().types()[i]) {
+          syncable::PostTimeToTypeHistogram(syncable::ModelType(i),
+                                            now - last_sync_time);
+        }
       }
     }
 
@@ -575,6 +595,7 @@
   bool nudged = false;
   NudgeSource nudge_source = kUnknown;
   syncable::ModelTypeBitSet model_types;
+  std::vector<std::string> payloads;
   // Has the previous sync cycle completed?
   if (continue_sync_cycle)
     nudge_source = kContinuation;
@@ -584,12 +605,14 @@
     if (!was_throttled) {
       nudge_source = vault_.pending_nudge_source_;
       model_types = vault_.pending_nudge_types_;
+      payloads = vault_.datatype_payloads_;
       nudged = true;
     }
     VLOG(1) << "Clearing pending nudge from " << vault_.pending_nudge_source_
             << " at tick " << vault_.pending_nudge_time_.ToInternalValue();
     vault_.pending_nudge_source_ = kUnknown;
     vault_.pending_nudge_types_.reset();
+    vault_.datatype_payloads_.clear();
     vault_.pending_nudge_time_ = base::TimeTicks();
   }
 
@@ -599,12 +622,12 @@
   // from syncer having more work to do.  This will be handled properly with
   // the message loop based syncer thread, bug 26339.
   return MakeSyncSourceInfo(nudged || nudge_source == kContinuation,
-      nudge_source, model_types, initial_sync);
+      nudge_source, model_types, payloads, initial_sync);
 }
 
 SyncSourceInfo SyncerThread::MakeSyncSourceInfo(bool nudged,
     NudgeSource nudge_source, const syncable::ModelTypeBitSet& nudge_types,
-    bool* initial_sync) {
+    const std::vector<std::string>& payloads, bool* initial_sync) {
   sync_pb::GetUpdatesCallerInfo::GetUpdatesSource updates_source =
       sync_pb::GetUpdatesCallerInfo::UNKNOWN;
   if (*initial_sync) {
@@ -632,7 +655,23 @@
         break;
     }
   }
-  return SyncSourceInfo(updates_source, nudge_types);
+
+  syncable::ModelTypeBitSet sync_source_types;
+  if (nudge_types.none()) {
+    // No datatypes requested. This must be a poll so set all enabled datatypes.
+    DCHECK(payloads.empty());  // There should be no payloads
+    ModelSafeRoutingInfo routes;
+    session_context_->registrar()->GetModelSafeRoutingInfo(&routes);
+    for (ModelSafeRoutingInfo::const_iterator i = routes.begin();
+         i != routes.end(); ++i) {
+      sync_source_types.set(i->first);
+    }
+
+  } else {
+    sync_source_types = nudge_types;
+  }
+
+  return SyncSourceInfo(updates_source, sync_source_types, payloads);
 }
 
 void SyncerThread::CreateSyncer(const std::string& dirname) {
@@ -736,7 +775,8 @@
 // Called with mutex_ already locked.
 void SyncerThread::NudgeSyncImpl(int milliseconds_from_now,
                                  NudgeSource source,
-                                 const syncable::ModelTypeBitSet& model_types) {
+                                 const syncable::ModelTypeBitSet& model_types,
+                                 const std::vector<std::string>& payloads) {
   // TODO(sync): Add the option to reset the backoff state machine.
   // This is needed so nudges that are a result of the user's desire
   // to download updates for a new data type can be satisfied quickly.
@@ -753,6 +793,21 @@
   // if pending_source is kLocal and |source| is kClearPrivateData).
   vault_.pending_nudge_types_ |= model_types;
 
+  // Any nudge results in the payloads vector at least having an empty string
+  // for each datatype. Any datatype that does actually have a payload signifies
+  // that we are requesting that datatype (and hence the corresponding
+  // |pending_nudge_types_| slot should be set).
+  vault_.datatype_payloads_.resize(syncable::MODEL_TYPE_COUNT);
+  for (size_t i = syncable::FIRST_REAL_MODEL_TYPE;
+       i < payloads.size();
+       ++i) {
+    if (!payloads[i].empty()) {
+      // This datatype has a payload we should hold on to.
+      vault_.pending_nudge_types_.set(i);
+      vault_.datatype_payloads_[i] = payloads[i];  // Overwrite old payloads.

[akalin, 2011/01/12 09:55:19]

why can we get away with overwriting?  Don't we need to merge (or is it already
merged)?

[Nicolas Zea, 2011/01/13 19:17:30]

We merge across datatypes, but if we receive a payload for datatype x at time 1,
then a different payload for datatype x at time 2, we're only concerned about
the most recent version of datatype x, which is based on the most recent
payload. Feel free to correct if my logic is wrong.

[akalin, 2011/01/13 19:47:41]

Okay, if that's the case, maybe expand the comment, like "// Overwrite old
payloads as we only need to send the most recent one."

[Nicolas Zea, 2011/01/18 06:07:23]

Done.

+    }
+  }
+
   const TimeTicks nudge_time = TimeTicks::Now() +
       TimeDelta::FromMilliseconds(milliseconds_from_now);
   if (nudge_time <= vault_.pending_nudge_time_) {