From 2b883e4f4318dea02d83e8730e04098e95aab9af Mon Sep 17 00:00:00 2001
From: Lasse Herskind <16536249+LHerskind@users.noreply.github.com>
Date: Wed, 24 Nov 2021 10:18:22 +0000
Subject: [PATCH] fix: Adapt code to support >128 reserves

---
 .../protocol/lendingpool/LendingPool.sol      |  4 +-
 .../configuration/UserConfiguration.sol       | 51 ++++++++++++++-----
 .../protocol/libraries/types/DataTypes.sol    |  2 +-
 3 files changed, 40 insertions(+), 17 deletions(-)

diff --git a/contracts/protocol/lendingpool/LendingPool.sol b/contracts/protocol/lendingpool/LendingPool.sol
index 8e38650c..304fa3a6 100644
--- a/contracts/protocol/lendingpool/LendingPool.sol
+++ b/contracts/protocol/lendingpool/LendingPool.sol
@@ -87,7 +87,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
     _addressesProvider = provider;
     _maxStableRateBorrowSizePercent = 2500;
     _flashLoanPremiumTotal = 9;
-    _maxNumberOfReserves = 128;
+    _maxNumberOfReserves = UserConfiguration._maxReserves;
   }
 
   /**
@@ -713,7 +713,7 @@ contract LendingPool is VersionedInitializable, ILendingPool, LendingPoolStorage
   }
 
   /**
-   * @dev Returns the fee on flash loans 
+   * @dev Returns the fee on flash loans
    */
   function FLASHLOAN_PREMIUM_TOTAL() public view returns (uint256) {
     return _flashLoanPremiumTotal;
diff --git a/contracts/protocol/libraries/configuration/UserConfiguration.sol b/contracts/protocol/libraries/configuration/UserConfiguration.sol
index 2994f05d..fed8ffda 100644
--- a/contracts/protocol/libraries/configuration/UserConfiguration.sol
+++ b/contracts/protocol/libraries/configuration/UserConfiguration.sol
@@ -13,6 +13,9 @@ library UserConfiguration {
   uint256 internal constant BORROWING_MASK =
     0x5555555555555555555555555555555555555555555555555555555555555555;
 
+  uint256 internal constant _maxReserves = 256;
+  uint256 internal constant _indexCount = _maxReserves / 128 + ((_maxReserves % 128 > 0) ? 1 : 0);
+
   /**
    * @dev Sets if the user is borrowing the reserve identified by reserveIndex
    * @param self The configuration object
@@ -24,9 +27,11 @@ library UserConfiguration {
     uint256 reserveIndex,
     bool borrowing
   ) internal {
-    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
-    self.data =
-      (self.data & ~(1 << (reserveIndex * 2))) |
+    require(reserveIndex < _maxReserves, Errors.UL_INVALID_INDEX);
+    uint256 index = reserveIndex / 128;
+    reserveIndex = reserveIndex % 128;
+    self.data[index] =
+      (self.data[index] & ~(1 << (reserveIndex * 2))) |
       (uint256(borrowing ? 1 : 0) << (reserveIndex * 2));
   }
 
@@ -41,9 +46,11 @@ library UserConfiguration {
     uint256 reserveIndex,
     bool usingAsCollateral
   ) internal {
-    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
-    self.data =
-      (self.data & ~(1 << (reserveIndex * 2 + 1))) |
+    require(reserveIndex < _maxReserves, Errors.UL_INVALID_INDEX);
+    uint256 index = reserveIndex / 128;
+    reserveIndex = reserveIndex % 128;
+    self.data[index] =
+      (self.data[index] & ~(1 << (reserveIndex * 2 + 1))) |
       (uint256(usingAsCollateral ? 1 : 0) << (reserveIndex * 2 + 1));
   }
 
@@ -57,8 +64,10 @@ library UserConfiguration {
     DataTypes.UserConfigurationMap memory self,
     uint256 reserveIndex
   ) internal pure returns (bool) {
-    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
-    return (self.data >> (reserveIndex * 2)) & 3 != 0;
+    require(reserveIndex < _maxReserves, Errors.UL_INVALID_INDEX);
+    uint256 index = reserveIndex / 128;
+    reserveIndex = reserveIndex % 128;
+    return (self.data[index] >> (reserveIndex * 2)) & 3 != 0;
   }
 
   /**
@@ -72,8 +81,10 @@ library UserConfiguration {
     pure
     returns (bool)
   {
-    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
-    return (self.data >> (reserveIndex * 2)) & 1 != 0;
+    require(reserveIndex < _maxReserves, Errors.UL_INVALID_INDEX);
+    uint256 index = reserveIndex / 128;
+    reserveIndex = reserveIndex % 128;
+    return (self.data[index] >> (reserveIndex * 2)) & 1 != 0;
   }
 
   /**
@@ -87,8 +98,10 @@ library UserConfiguration {
     pure
     returns (bool)
   {
-    require(reserveIndex < 128, Errors.UL_INVALID_INDEX);
-    return (self.data >> (reserveIndex * 2 + 1)) & 1 != 0;
+    require(reserveIndex < _maxReserves, Errors.UL_INVALID_INDEX);
+    uint256 index = reserveIndex / 128;
+    reserveIndex = reserveIndex % 128;
+    return (self.data[index] >> (reserveIndex * 2 + 1)) & 1 != 0;
   }
 
   /**
@@ -97,7 +110,12 @@ library UserConfiguration {
    * @return True if the user has been borrowing any reserve, false otherwise
    **/
   function isBorrowingAny(DataTypes.UserConfigurationMap memory self) internal pure returns (bool) {
-    return self.data & BORROWING_MASK != 0;
+    for (uint8 i = 0; i < _indexCount; i++) {
+      if (self.data[i] & BORROWING_MASK != 0) {
+        return true;
+      }
+    }
+    return false;
   }
 
   /**
@@ -106,6 +124,11 @@ library UserConfiguration {
    * @return True if the user has been borrowing any reserve, false otherwise
    **/
   function isEmpty(DataTypes.UserConfigurationMap memory self) internal pure returns (bool) {
-    return self.data == 0;
+    for (uint8 i = 0; i < _indexCount; i++) {
+      if (self.data[i] != 0) {
+        return false;
+      }
+    }
+    return true;
   }
 }
diff --git a/contracts/protocol/libraries/types/DataTypes.sol b/contracts/protocol/libraries/types/DataTypes.sol
index a19e5efc..b3b76b15 100644
--- a/contracts/protocol/libraries/types/DataTypes.sol
+++ b/contracts/protocol/libraries/types/DataTypes.sol
@@ -42,7 +42,7 @@ library DataTypes {
   }
 
   struct UserConfigurationMap {
-    uint256 data;
+    uint256[2] data; // size is _maxReserves / 128 + ((_maxReserves % 128 > 0) ? 1 : 0), but need to be literal
   }
 
   enum InterestRateMode {NONE, STABLE, VARIABLE}