Allow TID filter in ovnidump

dump.c

@@ -15,6 +15,8 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+#define _GNU_SOURCE
+
 #include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -24,11 +26,15 @@
 #include <sys/stat.h>
 #include <stdatomic.h>
 #include <dirent.h> 
+#include <unistd.h>
 
 #include "ovni.h"
 #include "trace.h"
 #include "emu.h"
 
+int filter_tid = -1;
+char *tracedir;
+
 //static void
 //hexdump(uint8_t *buf, size_t size)
 //{
@@ -88,6 +94,10 @@ dump_events(struct ovni_trace *trace)
 	for(i=0; i<trace->nstreams; i++)
 	{
 		stream = &trace->stream[i];
+
+		/* It can be inactive if it has been disabled by the
+		 * thread TID filter */
+		if(stream->active)
 			ovni_load_next_event(stream);
 	}
 
@@ -142,26 +152,56 @@ dump_events(struct ovni_trace *trace)
 	}
 }
 
+static void
+usage(int argc, char *argv[])
+{
+	UNUSED(argc);
+	UNUSED(argv);
+
+	err("Usage: ovnidump [-t TID] tracedir\n");
+	err("\n");
+	err("Dumps the events of the trace to the standard output.\n");
+	err("\n");
+	err("Options:\n");
+	err("  -t TID      Only events from the given TID are shown\n");
+	err("\n");
+	err("  tracedir    The trace directory generated by ovni.\n");
+	err("\n");
+
+	exit(EXIT_FAILURE);
+}
+
+static void
+parse_args(int argc, char *argv[])
+{
+	int opt;
+
+	while((opt = getopt(argc, argv, "t:")) != -1)
+	{
+		switch(opt)
+		{
+			case 't':
+				filter_tid = atoi(optarg);
+				break;
+			default: /* '?' */
+				usage(argc, argv);
+		}
+	}
+
+	if(optind >= argc)
+	{
+		err("missing tracedir\n");
+		usage(argc, argv);
+	}
+
+	tracedir = argv[optind];
+}
+
 int main(int argc, char *argv[])
 {
-	char *tracedir;
-	struct ovni_trace *trace;
+	parse_args(argc, argv);
 
-	trace = calloc(1, sizeof(struct ovni_trace));
-
-	if(trace == NULL)
-	{
-		perror("calloc");
-		exit(EXIT_FAILURE);
-	}
-
-	if(argc != 2)
-	{
-		fprintf(stderr, "missing tracedir\n");
-		exit(EXIT_FAILURE);
-	}
-
-	tracedir = argv[1];
+	struct ovni_trace *trace = calloc(1, sizeof(struct ovni_trace));
 
 	if(ovni_load_trace(trace, tracedir))
 		return 1;
@@ -169,6 +209,17 @@ int main(int argc, char *argv[])
 	if(ovni_load_streams(trace))
 		return 1;
 
+	if(filter_tid != -1)
+	{
+		for(size_t i=0; i<trace->nstreams; i++)
+		{
+			struct ovni_stream *stream;
+			stream = &trace->stream[i];
+			if(stream->tid != filter_tid)
+				stream->active = 0;
+		}
+	}
+
 	dump_events(trace);
 
 	ovni_free_streams(trace);