Increase test coverage for addrman and addrinfo

Adds several unittests for CAddrMan and CAddrInfo.
Increases the accuracy of addrman tests.
Removes non-determinism in tests by overriding the random number generator.
Extracts testing code from addrman class to test class.

Author: EthanHeilman

src/addrman.cpp

@@ -224,7 +224,7 @@ void CAddrMan::Good_(const CService& addr, int64_t nTime)
         return;
 
     // find a bucket it is in now
-    int nRnd = GetRandInt(ADDRMAN_NEW_BUCKET_COUNT);
+    int nRnd = RandomInt(ADDRMAN_NEW_BUCKET_COUNT);
     int nUBucket = -1;
     for (unsigned int n = 0; n < ADDRMAN_NEW_BUCKET_COUNT; n++) {
         int nB = (n + nRnd) % ADDRMAN_NEW_BUCKET_COUNT;
@@ -281,7 +281,7 @@ bool CAddrMan::Add_(const CAddress& addr, const CNetAddr& source, int64_t nTimeP
         int nFactor = 1;
         for (int n = 0; n < pinfo->nRefCount; n++)
             nFactor *= 2;
-        if (nFactor > 1 && (GetRandInt(nFactor) != 0))
+        if (nFactor > 1 && (RandomInt(nFactor) != 0))
             return false;
     } else {
         pinfo = Create(addr, source, &nId);
@@ -342,37 +342,37 @@ CAddrInfo CAddrMan::Select_(bool newOnly)
         return CAddrInfo();
 
     // Use a 50% chance for choosing between tried and new table entries.
-    if (!newOnly && (nTried > 0 && (nNew == 0 || GetRandInt(2) == 0))) {
+    if (!newOnly && (nTried > 0 && (nNew == 0 || RandomInt(2) == 0))) {
         // use a tried node
         double fChanceFactor = 1.0;
         while (1) {
-            int nKBucket = GetRandInt(ADDRMAN_TRIED_BUCKET_COUNT);
-            int nKBucketPos = GetRandInt(ADDRMAN_BUCKET_SIZE);
+            int nKBucket = RandomInt(ADDRMAN_TRIED_BUCKET_COUNT);
+            int nKBucketPos = RandomInt(ADDRMAN_BUCKET_SIZE);
             while (vvTried[nKBucket][nKBucketPos] == -1) {
                 nKBucket = (nKBucket + insecure_rand()) % ADDRMAN_TRIED_BUCKET_COUNT;
                 nKBucketPos = (nKBucketPos + insecure_rand()) % ADDRMAN_BUCKET_SIZE;
             }
             int nId = vvTried[nKBucket][nKBucketPos];
             assert(mapInfo.count(nId) == 1);
             CAddrInfo& info = mapInfo[nId];
-            if (GetRandInt(1 << 30) < fChanceFactor * info.GetChance() * (1 << 30))
+            if (RandomInt(1 << 30) < fChanceFactor * info.GetChance() * (1 << 30))
                 return info;
             fChanceFactor *= 1.2;
         }
     } else {
         // use a new node
         double fChanceFactor = 1.0;
         while (1) {
-            int nUBucket = GetRandInt(ADDRMAN_NEW_BUCKET_COUNT);
-            int nUBucketPos = GetRandInt(ADDRMAN_BUCKET_SIZE);
+            int nUBucket = RandomInt(ADDRMAN_NEW_BUCKET_COUNT);
+            int nUBucketPos = RandomInt(ADDRMAN_BUCKET_SIZE);
             while (vvNew[nUBucket][nUBucketPos] == -1) {
                 nUBucket = (nUBucket + insecure_rand()) % ADDRMAN_NEW_BUCKET_COUNT;
                 nUBucketPos = (nUBucketPos + insecure_rand()) % ADDRMAN_BUCKET_SIZE;
             }
             int nId = vvNew[nUBucket][nUBucketPos];
             assert(mapInfo.count(nId) == 1);
             CAddrInfo& info = mapInfo[nId];
-            if (GetRandInt(1 << 30) < fChanceFactor * info.GetChance() * (1 << 30))
+            if (RandomInt(1 << 30) < fChanceFactor * info.GetChance() * (1 << 30))
                 return info;
             fChanceFactor *= 1.2;
         }
@@ -468,7 +468,7 @@ void CAddrMan::GetAddr_(std::vector<CAddress>& vAddr)
         if (vAddr.size() >= nNodes)
             break;
 
-        int nRndPos = GetRandInt(vRandom.size() - n) + n;
+        int nRndPos = RandomInt(vRandom.size() - n) + n;
         SwapRandom(n, nRndPos);
         assert(mapInfo.count(vRandom[n]) == 1);
 
@@ -497,3 +497,7 @@ void CAddrMan::Connected_(const CService& addr, int64_t nTime)
     if (nTime - info.nTime > nUpdateInterval)
         info.nTime = nTime;
 }
+
+int CAddrMan::RandomInt(int nMax){
+    return GetRandInt(nMax);
+}

src/addrman.h

@@ -176,9 +176,6 @@ class CAddrMan
     //! critical section to protect the inner data structures
     mutable CCriticalSection cs;
 
-    //! secret key to randomize bucket select with
-    uint256 nKey;
-
     //! last used nId
     int nIdCount;
 
@@ -204,6 +201,9 @@ class CAddrMan
     int vvNew[ADDRMAN_NEW_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE];
 
 protected:
+    //! secret key to randomize bucket select with
+    uint256 nKey;
+
     //! Find an entry.
     CAddrInfo* Find(const CNetAddr& addr, int* pnId = NULL);
 
@@ -235,6 +235,9 @@ class CAddrMan
     //! Select an address to connect to, if newOnly is set to true, only the new table is selected from.
     CAddrInfo Select_(bool newOnly);
 
+    //! Wraps GetRandInt to allow tests to override RandomInt and make it determinismistic.
+    virtual int RandomInt(int nMax);
+
 #ifdef DEBUG_ADDRMAN
     //! Perform consistency check. Returns an error code or zero.
     int Check_();
@@ -570,12 +573,6 @@ class CAddrMan
             Check();
         }
     }
-
-    //! Ensure that bucket placement is always the same for testing purposes.
-    void MakeDeterministic(){
-        nKey.SetNull(); //Do not use outside of tests.
-    }
-
 };
 
 #endif // BITCOIN_ADDRMAN_H