hashrate: format units based on the value size

ccminer.cpp

@@ -1483,9 +1483,8 @@ static void *miner_thread(void *userdata)
 
 		/* output */
 		if (!opt_quiet && loopcnt) {
-			sprintf(s, thr_hashrates[thr_id] >= 1e6 ? "%.0f" : "%.2f",
-				1e-3 * thr_hashrates[thr_id]);
-			applog(LOG_INFO, "GPU #%d: %s, %s kH/s",
+			format_hashrate(thr_hashrates[thr_id], s);
+			applog(LOG_INFO, "GPU #%d: %s, %s",
 				device_map[thr_id], device_name[device_map[thr_id]], s);
 		}
 
@@ -1497,8 +1496,8 @@ static void *miner_thread(void *userdata)
 				hashrate += stats_get_speed(i, thr_hashrates[i]);
 			pthread_mutex_unlock(&stats_lock);
 			if (opt_benchmark) {
-				sprintf(s, hashrate >= 1e6 ? "%.0f" : "%.2f", hashrate / 1000.);
-				applog(LOG_NOTICE, "Total: %s kH/s", s);
+				format_hashrate(hashrate, s);
+				applog(LOG_NOTICE, "Total: %s", s);
 			}
 
 			// X-Mining-Hashrate

miner.h

@@ -517,6 +517,7 @@ extern uint32_t gpus_intensity[MAX_GPUS];
 
 #define CL_WHT  "\x1B[01;37m" /* white */
 
+extern void format_hashrate(double hashrate, char *output);
 extern void applog(int prio, const char *fmt, ...);
 void get_defconfig_path(char *out, size_t bufsize, char *argv0);
 extern json_t *json_rpc_call(CURL *curl, const char *url, const char *userpass,

util.cpp

@@ -173,6 +173,60 @@ void get_defconfig_path(char *out, size_t bufsize, char *argv0)
 #endif
 }
 
+void format_hashrate(double hashrate, char *output)
+{
+	char prefix;
+
+	if (hashrate < 1e3)
+		prefix = ' ';
+	else if (hashrate < 1e6)
+	{
+		prefix = 'k';
+		hashrate *= 1e-3;
+	}
+	else if (hashrate < 1e9)
+	{
+		prefix = 'M';
+		hashrate *= 1e-6;
+	}
+	else if (hashrate < 1e12)
+	{
+		prefix = 'G';
+		hashrate *= 1e-9;
+	}
+	else if (hashrate < 1e15)
+	{
+		prefix = 'T';
+		hashrate *= 1e-12;
+	}
+	else if (hashrate < 1e18)
+	{
+		prefix = 'P';
+		hashrate *= 1e-15;
+	}
+	else if (hashrate < 1e21)
+	{
+		prefix = 'E';
+		hashrate *= 1e-18;
+	}
+	else if (hashrate < 1e24)
+	{
+		prefix = 'Z';
+		hashrate *= 1e-21;
+	}
+	else
+	{
+		prefix = 'Y';
+		hashrate *= 1e-24;
+	}
+
+	sprintf(
+		output,
+		prefix == ' ' ? "%.0f%cH/s" : "%.2f %cH/s",
+		hashrate, prefix
+	);
+}
+
 static void databuf_free(struct data_buffer *db)
 {
 	if (!db)