From 08843fa1763723edec3f01b98dc2edbd9946d65d Mon Sep 17 00:00:00 2001
From: MestryOmkar <mestryomkar@gmail.com>
Date: Mon, 10 Dec 2018 11:12:07 +0530
Subject: [PATCH] set min gas price for tx

---
 core/tx_pool.go | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/core/tx_pool.go b/core/tx_pool.go
index 63dbf3ac9e..496f881787 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -81,7 +81,11 @@ var (
 
 	ErrZeroGasPrice = errors.New("zero gas price")
 
+	ErrUnderMinGasPrice = errors.New("under min gas price")
+
 	ErrDuplicateSpecialTransaction = errors.New("duplicate a special transaction")
+
+	ErrMinDeploySMC = errors.New("smart contract creation cost is under allowance")
 )
 
 var (
@@ -587,7 +591,7 @@ func (pool *TxPool) validateTx(tx *types.Transaction, local bool) error {
 	}
 	// Drop non-local transactions under our own minimal accepted gas price
 	local = local || pool.locals.contains(from) // account may be local even if the transaction arrived from the network
-	if !local && tx.To() != nil && pool.gasPrice.Cmp(tx.GasPrice()) > 0 {
+	if !local && pool.gasPrice.Cmp(tx.GasPrice()) > 0 {
 		if !tx.IsSpecialTransaction() || (pool.IsMasterNode != nil && !pool.IsMasterNode(from)) {
 			return ErrUnderpriced
 		}
@@ -619,6 +623,16 @@ func (pool *TxPool) validateTx(tx *types.Transaction, local bool) error {
 		if tx.GasPrice().Cmp(new(big.Int).SetInt64(0)) == 0 {
 			return ErrZeroGasPrice
 		}
+
+		// under min gas price
+		if tx.GasPrice().Cmp(new(big.Int).SetInt64(common.MinGasPrice)) < 0 {
+			return ErrUnderMinGasPrice
+		}
+	}
+
+	minGasDeploySMC := new(big.Int).Mul(new(big.Int).SetUint64(10), new(big.Int).SetUint64(params.Ether))
+	if tx.To() == nil && (tx.Cost().Cmp(minGasDeploySMC) < 0 || tx.GasPrice().Cmp(new(big.Int).SetUint64(10000*params.Shannon)) < 0) {
+		return ErrMinDeploySMC
 	}
 
 	return nil
@@ -1229,4 +1243,4 @@ func (as *accountSet) containsTx(tx *types.Transaction) bool {
 // add inserts a new address into the set to track.
 func (as *accountSet) add(addr common.Address) {
 	as.accounts[addr] = struct{}{}
-}
+}
\ No newline at end of file