IDBObserver: Lifetime Management: Adding Observer

content/browser/indexed_db/indexed_db_connection.cc

Index: content/browser/indexed_db/indexed_db_connection.cc
diff --git a/content/browser/indexed_db/indexed_db_connection.cc b/content/browser/indexed_db/indexed_db_connection.cc
index f7133a69230da18b88b9deb75e84775823d9467e..469ba1b41f1d087262946f70f5bb8ce82c52dca8 100644
--- a/content/browser/indexed_db/indexed_db_connection.cc
+++ b/content/browser/indexed_db/indexed_db_connection.cc
@@ -4,6 +4,9 @@
 
 #include "content/browser/indexed_db/indexed_db_connection.h"
 
+#include "base/logging.h"
+#include "base/stl_util.h"
+
 namespace content {
 
 IndexedDBConnection::IndexedDBConnection(
@@ -21,6 +24,7 @@ void IndexedDBConnection::Close() {
   if (this_obj) {
     database_ = nullptr;
     callbacks_ = nullptr;
+    active_observers_.clear();
   }
 }
 
@@ -35,6 +39,7 @@ void IndexedDBConnection::ForceClose() {
   if (this_obj) {
     database_ = nullptr;
     callbacks_ = nullptr;
+    active_observers_.clear();
   }
   callbacks->OnForcedClose();
 }
@@ -49,4 +54,36 @@ bool IndexedDBConnection::IsConnected() {
   return database_.get() != NULL;
 }
 
+void IndexedDBConnection::ActivatePendingObservers(
+    std::vector<std::unique_ptr<IndexedDBObserver>> pending_observers) {
+  for (uint32_t i = 0; i < pending_observers.size(); i++) {
+    active_observers_.push_back(std::move(pending_observers[i]));
+  }
+  // pending_observers->clear();

[dmurph, 2016/06/27 21:20:51]

Probably safe to clear here.

[palakj1, 2016/06/27 23:13:08]

Done. Is it okay to pass the argument by value?

+}
+
+void IndexedDBConnection::RemoveObservers(
+    const std::vector<int32_t>& observer_ids_to_remove) {
+  // TODO(palakj): Change from vector to set or create tmp vector instead of
+  // erase.
+  std::vector<int32_t> pending_observer_ids;
+  for (int32_t id_to_remove : observer_ids_to_remove) {
+    bool removed = false;
+    for (size_t j = 0; j < active_observers_.size(); j++) {
+      if (active_observers_[j]->id() == id_to_remove) {
+        active_observers_.erase(active_observers_.begin() + j);

[dmurph, 2016/06/27 21:20:51]

Again, this won't work. You'll remove the item at 'i', which shifts the array
back to that the item at 'i' is different, then you increment and skip that
item.

Ok, so let's do the temp vector route. If the ids don't match, add it to the
temporary vector, and then swap them at the end. Then, you can send that active
list to the database.

[dmurph, 2016/06/27 21:44:06]

Nevermind, this works.

+        removed = true;
+        break;
+      }
+    }
+    // If observer not in active_observers_ , must be in pending_observer list
+    // of one of the transactions.
+    if (!removed) {
+      pending_observer_ids.push_back(id_to_remove);
+    }
+  }
+  if (!pending_observer_ids.empty())
+    database_->RemovePendingObservers(this, pending_observer_ids);
+}
+
 }  // namespace content