Add a snapshot dumping function into pg_dtm for debugging.

kvap · kvap · commit bca149517164 · 2015-09-16T02:19:28.000+03:00
diff --git a/contrib/pg_xtm/libdtm.c b/contrib/pg_xtm/libdtm.c
@@ -233,11 +233,11 @@ bool DtmGlobalGetSnapshot(DTMConn dtm, NodeId nodeid, TransactionId xid, Snapsho
 		Assert(s->xip[i] == number); // the number should fit into xip[i] size
 	}
 
-	fprintf(stdout, "snapshot: xmin = %#x, xmax = %#x, active =", s->xmin, s->xmax);
-	for (i = 0; i < s->xcnt; i++) {
-		fprintf(stdout, " %#x", s->xip[i]);
-	}
-	fprintf(stdout, "\n");
+	//fprintf(stdout, "snapshot: xmin = %#x, xmax = %#x, active =", s->xmin, s->xmax);
+	//for (i = 0; i < s->xcnt; i++) {
+	//	fprintf(stdout, " %#x", s->xip[i]);
+	//}
+	//fprintf(stdout, "\n");
 
 	return true;
 }
diff --git a/contrib/pg_xtm/pg_dtm.c b/contrib/pg_xtm/pg_dtm.c
@@ -70,6 +70,27 @@ static void DtmEnsureConnection(void)
     }
 }
 
+static void DumpSnapshot(Snapshot s, char *name)
+{
+	int i;
+	char buf[10000];
+	char *cursor = buf;
+	cursor += sprintf(
+		cursor,
+		"snapshot %s: xmin=%d, xmax=%d, active=[",
+		name, s->xmin, s->xmax
+	);
+	for (i = 0; i < s->xcnt; i++) {
+		if (i == 0) {
+			cursor += sprintf(cursor, "%d", s->xip[i]);
+		} else {
+			cursor += sprintf(cursor, ", %d", s->xip[i]);
+		}
+	}
+	cursor += sprintf(cursor, "]");
+	XTM_TRACE("%s\n", buf);
+}
+
 static void DtmCopySnapshot(Snapshot dst, Snapshot src)
 {
     int i, j, n;
