Modernize C by changing #define constants to enum

lib/instructions/instruction_metrics.c

@@ -5,30 +5,33 @@
 #include <evmc/instructions.h>
 
 /**
- * Marks an instruction as undefined.
- *
- * The gas cost for undefined instructions is 0 because this is the cost of executing them
- * in practice in EVM implementations.
+ * Gas cost tiers, names from Yellow Paper.
  */
-#define UNDEFINED 0
-
-/**
- * Gas price tiers, names from Yellow Paper.
- * @{
- */
-#define ZERO 0
-#define BASE 2
-#define VERYLOW 3
-#define LOW 5
-#define MID 8
-#define HIGH 10
+enum
+{
+    ZERO = 0,
+    BASE = 2,
+    VERYLOW = 3,
+    LOW = 5,
+    MID = 8,
+    HIGH = 10,
 
-/** @} */
+    /**
+     * Marks an instruction as undefined.
+     *
+     * The gas cost for undefined instructions is 0 because this is the cost of executing them
+     * in practice in EVM implementations.
+     */
+    UNDEFINED = ZERO
+};
 
-/**
- * Defined in EIP-2929: Gas cost increases for state access opcodes.
- */
-#define WARM_STORAGE_READ_COST 100
+enum
+{
+    /**
+     * Defined in EIP-2929: Gas cost increases for state access opcodes.
+     */
+    WARM_STORAGE_READ_COST = 100
+};
 
 
 static struct evmc_instruction_metrics cancun_metrics[256] = {

lib/loader/loader.c

@@ -66,12 +66,14 @@ static
     return 0;
 }
 
-#define PATH_MAX_LENGTH 4096
+enum
+{
+    PATH_MAX_LENGTH = 4096,
+    LAST_ERROR_MSG_BUFFER_SIZE = 511
+};
 
 static const char* last_error_msg = NULL;
 
-#define LAST_ERROR_MSG_BUFFER_SIZE 511
-
 // Buffer for formatted error messages.
 // It has one null byte extra to avoid buffer read overflow during concurrent access.
 static char last_error_msg_buffer[LAST_ERROR_MSG_BUFFER_SIZE + 1];