Read and Write fee estimate file directly from CBlockPolicyEstimator

2 files changed, 35 insertions, 15 deletions

diff --git a/src/policy/fees.cpp b/src/policy/fees.cpp
index 66da753a8b..eed71089e4 100644
--- a/src/policy/fees.cpp
+++ b/src/policy/fees.cpp
@@ -7,6 +7,7 @@
 #include "policy/policy.h"
 
 #include "amount.h"
+#include "clientversion.h"
 #include "primitives/transaction.h"
 #include "random.h"
 #include "streams.h"
@@ -173,7 +174,7 @@ double TxConfirmStats::EstimateMedianVal(int confTarget, double sufficientTxVal,
     return median;
 }
 
-void TxConfirmStats::Write(CAutoFile& fileout)
+void TxConfirmStats::Write(CAutoFile& fileout) const
 {
     fileout << decay;
     fileout << buckets;
@@ -464,21 +465,40 @@ CFeeRate CBlockPolicyEstimator::estimateSmartFee(int confTarget, int *answerFoun
     return CFeeRate(median);
 }
 
-void CBlockPolicyEstimator::Write(CAutoFile& fileout)
+bool CBlockPolicyEstimator::Write(CAutoFile& fileout) const
 {
-    LOCK(cs_feeEstimator);
-    fileout << nBestSeenHeight;
-    feeStats.Write(fileout);
+    try {
+        LOCK(cs_feeEstimator);
+        fileout << 139900; // version required to read: 0.13.99 or later
+        fileout << CLIENT_VERSION; // version that wrote the file
+        fileout << nBestSeenHeight;
+        feeStats.Write(fileout);
+    }
+    catch (const std::exception&) {
+        LogPrintf("CBlockPolicyEstimator::Write(): unable to read policy estimator data (non-fatal)\n");
+        return false;
+    }
+    return true;
 }
 
-void CBlockPolicyEstimator::Read(CAutoFile& filein, int nFileVersion)
+bool CBlockPolicyEstimator::Read(CAutoFile& filein)
 {
-    LOCK(cs_feeEstimator);
-    int nFileBestSeenHeight;
-    filein >> nFileBestSeenHeight;
-    feeStats.Read(filein);
-    nBestSeenHeight = nFileBestSeenHeight;
-    // if nVersionThatWrote < 139900 then another TxConfirmStats (for priority) follows but can be ignored.
+    try {
+        LOCK(cs_feeEstimator);
+        int nVersionRequired, nVersionThatWrote, nFileBestSeenHeight;
+        filein >> nVersionRequired >> nVersionThatWrote;
+        if (nVersionRequired > CLIENT_VERSION)
+            return error("CBlockPolicyEstimator::Read(): up-version (%d) fee estimate file", nVersionRequired);
+        filein >> nFileBestSeenHeight;
+        feeStats.Read(filein);
+        nBestSeenHeight = nFileBestSeenHeight;
+        // if nVersionThatWrote < 139900 then another TxConfirmStats (for priority) follows but can be ignored.
+    }
+    catch (const std::exception&) {
+        LogPrintf("CBlockPolicyEstimator::Read(): unable to read policy estimator data (non-fatal)\n");
+        return false;
+    }
+    return true;
 }
 
 FeeFilterRounder::FeeFilterRounder(const CFeeRate& minIncrementalFee)
diff --git a/src/policy/fees.h b/src/policy/fees.h
index 2299144b94..d11de81ee3 100644
--- a/src/policy/fees.h
+++ b/src/policy/fees.h
@@ -156,7 +156,7 @@ public:
     unsigned int GetMaxConfirms() const { return confAvg.size(); }
 
     /** Write state of estimation data to a file*/
-    void Write(CAutoFile& fileout);
+    void Write(CAutoFile& fileout) const;
 
     /**
      * Read saved state of estimation data from a file and replace all internal data structures and
@@ -226,10 +226,10 @@ public:
     CFeeRate estimateSmartFee(int confTarget, int *answerFoundAtTarget, const CTxMemPool& pool) const;
 
     /** Write estimation data to a file */
-    void Write(CAutoFile& fileout);
+    bool Write(CAutoFile& fileout) const;
 
     /** Read estimation data from a file */
-    void Read(CAutoFile& filein, int nFileVersion);
+    bool Read(CAutoFile& filein);
 
 private:
     CFeeRate minTrackedFee;    //!< Passed to constructor to avoid dependency on main