From 444010ea3c3183af00f9726795a446481949c5c2 Mon Sep 17 00:00:00 2001
From: Tapan Karwa <tkarwa@juniper.net>
Date: Wed, 29 Apr 2015 16:13:59 -0700
Subject: [PATCH] Fix for assert in IFMapExporter::StateUpdateOnDequeue

The following sequences causes the problem. Fixing it:
The sequence is:
1. Exporter gets an add or change. Exporter processes it and adds it to the
queue as an 'update'.
2. The queue 'update' has not been processed yet and exporter gets a delete for
the node.
3. The queue 'update' (not 'delete') is processed leading to the assert being
true.

Change-Id: I38b6d1dbedaaafe8d631276d5c97b1485e6a2f42
Closes-Bug: 1430091
---
 src/ifmap/ifmap_exporter.cc | 2 +-
 src/ifmap/ifmap_update.h    | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/ifmap/ifmap_exporter.cc b/src/ifmap/ifmap_exporter.cc
index ac47dd519ac..53ed297225c 100644
--- a/src/ifmap/ifmap_exporter.cc
+++ b/src/ifmap/ifmap_exporter.cc
@@ -544,7 +544,7 @@ void IFMapExporter::StateUpdateOnDequeue(IFMapUpdate *update,
     }
     if (update->advertise().empty()) {
         state->Remove(update);
-        if (state->update_list().empty() && state->IsInvalid()) {
+        if (state->CanDelete()) {
             assert(state->advertised().empty());
             db_entry->ClearState(table, TableListenerId(table));
             delete state;
diff --git a/src/ifmap/ifmap_update.h b/src/ifmap/ifmap_update.h
index 02ef713f780..1fc1c48855a 100644
--- a/src/ifmap/ifmap_update.h
+++ b/src/ifmap/ifmap_update.h
@@ -134,6 +134,7 @@ class IFMapState : public DBState {
     virtual bool IsInvalid() const { return sig_ == kInvalidSig; }
     const crc32type &crc() const { return crc_; }
     void SetCrc(crc32type &crc) { crc_ = crc; }
+    virtual bool CanDelete() = 0;
 
 protected:
     static const uint32_t kInvalidSig = -1;
@@ -171,6 +172,9 @@ class IFMapNodeState : public IFMapState {
     const BitSet &nmask() const { return nmask_; }
     void nmask_clear() { nmask_.clear(); }
     void nmask_set(int bit) { nmask_.set(bit); }
+    virtual bool CanDelete() {
+        return (update_list().empty() && IsInvalid() && !HasDependents());
+    }
 
 private:
     DEPENDENCY_LIST(IFMapLink, IFMapNodeState, dependents_);
@@ -189,6 +193,9 @@ class IFMapLinkState : public IFMapState {
 
     IFMapNodeState *left() { return left_.get(); }
     IFMapNodeState *right() { return right_.get(); }
+    virtual bool CanDelete() {
+        return (update_list().empty() && IsInvalid());
+    }
 
 private:
     DependencyRef<IFMapLink, IFMapNodeState> left_;