Add timestamp field to transactions - allows multiple transactions with the same Ins/Outs

include/block/transaction.h

@@ -20,9 +20,10 @@ static inline bool Address_IsCoinbase(const uint8_t address[32]) {
     return true;
 }
 
-// 160 bytes total for v1
+// 168 bytes total for v1
 #pragma pack(push, 1) // Ensure no padding for consistent file storage
 typedef struct {
+    uint64_t timestamp; // Unix timestamp in seconds - not enforced, but used for uniqueness when everything else is the same.
     uint64_t fee; // Rewarded to the miner; can be zero, but the miner may choose to ignore transactions with very low fees
     uint64_t amount1;
     uint64_t amount2;

src/main.c

@@ -148,6 +148,7 @@ static void AddCoinbaseTransaction(block_t* block, const uint8_t minerAddress[32
     coinbaseTx.transaction.amount2 = 0;
     memset(coinbaseTx.transaction.compressedPublicKey, 0, sizeof(coinbaseTx.transaction.compressedPublicKey));
     memset(coinbaseTx.transaction.senderAddress, 0xFF, sizeof(coinbaseTx.transaction.senderAddress));
+    coinbaseTx.transaction.timestamp = (uint64_t)time(NULL);
     Block_AddTransaction(block, &coinbaseTx);
 }
 
@@ -1014,6 +1015,7 @@ int main(int argc, char* argv[]) {
             spendTx.transaction.fee = (uint64_t)fee;
             spendTx.transaction.amount1 = (uint64_t)amount;
             spendTx.transaction.amount2 = 0;
+            spendTx.transaction.timestamp = (uint64_t)time(NULL);
             memcpy(spendTx.transaction.senderAddress, minerAddress, sizeof(minerAddress));
             memcpy(spendTx.transaction.recipientAddress1, recipientAddress, sizeof(recipientAddress));
             memset(spendTx.transaction.recipientAddress2, 0, sizeof(spendTx.transaction.recipientAddress2));
@@ -1364,6 +1366,7 @@ int main(int argc, char* argv[]) {
             printf("  Amount1: %llu\n", (unsigned long long)tx.transaction.amount1);
             printf("  Amount2: %llu\n", (unsigned long long)tx.transaction.amount2);
             printf("  Fee: %llu\n", (unsigned long long)tx.transaction.fee);
+            printf("  Timestamp: %llu\n", (unsigned long long)tx.transaction.timestamp);
             continue;
         }