millisecond timestamps

include/utils.h

@@ -8,6 +8,7 @@
 #include <stdbool.h>
 #include <crypto/crypto.h>
 #include <uint256.h>
+#include <time.h>
 
 typedef struct {
     uint8_t bytes[32];
@@ -26,6 +27,15 @@ static inline int eq_key32(key32_t a, key32_t b) {
     return memcmp(a.bytes, b.bytes, 32) == 0;
 }
 
+static inline uint64_t get_current_time_ms(void) {
+    struct timespec spec;
+    if (clock_gettime(CLOCK_REALTIME, &spec) == -1) {
+        return 0; // Handle error
+    }
+    // Convert seconds to milliseconds and add nanoseconds converted to milliseconds
+    return (spec.tv_sec * 1000) + (spec.tv_nsec / 1000000);
+}
+
 static inline void AddressToHexString(const uint8_t address[32], char out[65]) {
     if (!address || !out) {
         return;

src/block/chain.c

@@ -804,6 +804,7 @@ uint32_t Chain_ComputeNextTarget(blockchain_t* chain, uint32_t currentTarget) {
 
     // Retarget uses whole-window span. Per-block average is implicit:
     // (actualTime / interval) / targetBlockTime == actualTime / targetTime.
+    // Block timestamps are stored in milliseconds, so the target window must be ms too.
     uint64_t actualTime = 0;
     if (lastBlock->header.timestamp > adjustmentBlock->header.timestamp) {
         actualTime = lastBlock->header.timestamp - adjustmentBlock->header.timestamp;
@@ -812,7 +813,7 @@ uint32_t Chain_ComputeNextTarget(blockchain_t* chain, uint32_t currentTarget) {
         return currentTarget; // Invalid/non-increasing time window; keep current target
     }
 
-    const uint64_t targetTime = (uint64_t)TARGET_BLOCK_TIME * (uint64_t)DIFFICULTY_ADJUSTMENT_INTERVAL;
+    const uint64_t targetTime = (uint64_t)TARGET_BLOCK_TIME * 1000ULL * (uint64_t)DIFFICULTY_ADJUSTMENT_INTERVAL;
     double timeRatio = (double)actualTime / (double)targetTime;
 
     // Clamp per-epoch target movement: at most x2 easier or x2 harder. TODO: Check if the clamp should be more aggressive or looser

src/main.c

@@ -85,7 +85,7 @@ static block_t* BuildNextBlock(blockchain_t* chain, uint32_t difficultyTarget) {
     } else {
         memset(block->header.prevHash, 0, sizeof(block->header.prevHash));
     }
-    block->header.timestamp = (uint64_t)time(NULL);
+    block->header.timestamp = (uint64_t)get_current_time_ms();
     block->header.difficultyTarget = difficultyTarget;
     block->header.nonce = 0;