Small modification to trace_dump.

It can now be used to make a dump from a trace stream on stdin.
Nice for taking a quick look at traces which were dumped to disk first.

common/trace/trace_dump.c

@@ -87,25 +87,45 @@ static void handler_value(struct trace *trace,
 	}
 }
 
+
+void usage(void)
+{
+	printf("Usage:\n\n");
+	printf("trace_dump [host] [port] [trace] <interval>\n");
+	
+	exit(0);
+}
+
 int main(int argc, char **argv)
 {
 	struct trace *trace;
 	struct trace_pkt *pkt;
 	int interval = 1;
 	uint64_t nsec_interval;
+	bool fromstdin = false;
 
-	if (argc < 4) {
-		printf("Usage:\n\n");
-		printf("%s [host] [port] [trace] <interval>\n", argv[0]);
-		return 0;
+	if (argc < 2) {
+		usage();
+	}
+	if (!strcmp(argv[1], "-")) {
+		fromstdin = true;
+	}
+	if (!fromstdin && argc < 4) {
+		usage();
 	}
 
-	tracename = argv[3];
+	if (!fromstdin) {
+		tracename = argv[3];
 
-	trace = trace_open(argv[1], atoi(argv[2]));
+		if (argc >= 5) {
+			interval = atoi(argv[4]);
+		}
+	
+		trace = trace_open(argv[1], atoi(argv[2]));
 
-	if (argc >= 5) {
-		interval = atoi(argv[4]);
+	} else {
+		trace = trace_alloc();
+		trace_initialize_fd(trace, 0);
 	}
 	
 	trace->handler_interval = handler_interval;
@@ -125,29 +145,31 @@ int main(int argc, char **argv)
 		trace_handle(trace, &fdrx);
 	}
 	
-	printf("Connection ready for tracing\n");
+	if (!fromstdin) {
+		printf("Connection ready for tracing\n");
 	
-	if (interval) {
-		nsec_interval = t_int.tv_sec * 1000000000;
-		nsec_interval += t_int.tv_nsec;
+		if (interval) {
+			nsec_interval = t_int.tv_sec * 1000000000;
+			nsec_interval += t_int.tv_nsec;
 		
-		nsec_interval *= interval;
+			nsec_interval *= interval;
 		
-		t_int.tv_nsec = nsec_interval % 1000000000;
-		t_int.tv_sec = nsec_interval / 1000000000;
-
+			t_int.tv_nsec = nsec_interval % 1000000000;
+			t_int.tv_sec = nsec_interval / 1000000000;
+
+			pkt = trace_packet_new();
+			trace_packet_interval_set(pkt, 
+			    &t_int, TRACE_INTERVAL_TYPE_INTERVAL);
+			trace_packet_write(trace, pkt);
+			trace_packet_put(pkt);
+		}
+	
 		pkt = trace_packet_new();
-		trace_packet_interval_set(pkt, 
-		    &t_int, TRACE_INTERVAL_TYPE_INTERVAL);
+		trace_packet_name_set(pkt, tracename);
 		trace_packet_write(trace, pkt);
 		trace_packet_put(pkt);
 	}
 
-	pkt = trace_packet_new();
-	trace_packet_name_set(pkt, tracename);
-	trace_packet_write(trace, pkt);
-	trace_packet_put(pkt);
-
 	printf("Wait for data\n");
 
 	while (trace_state_get(trace) == TRACE_STATE_RECEIVING ||