Dynamically calculate number of participants

knizhnik · knizhnik · commit e9335ab4dffa · 2015-10-01T19:27:30.000+03:00
diff --git a/contrib/pg_xtm/dtmd/include/transaction.h b/contrib/pg_xtm/dtmd/include/transaction.h
@@ -14,7 +14,8 @@
 typedef struct Transaction {
 	xid_t xid;
 
-	int size;
+	int size; // number of paritcipants
+	int max_size; // maximal number of participants
 
 	// for + against ≤ size
 	int votes_for;
diff --git a/contrib/pg_xtm/dtmd/src/main.c b/contrib/pg_xtm/dtmd/src/main.c
@@ -280,7 +280,8 @@ static char *onbegin(void *stream, void *clientdata, cmd_t *cmd) {
 
 	prev_gxid = t->xid = next_gxid++;
 	t->snapshots_count = 0;
-	t->size = size;
+	t->max_size = size;
+    t->size = 1;
 
 	CLIENT_SNAPSENT(clientdata) = 0;
 	CLIENT_XID(clientdata) = t->xid;
@@ -436,6 +437,12 @@ static char *onsnapshot(void *stream, void *clientdata, cmd_t *cmd) {
 	if (CLIENT_XID(clientdata) == INVALID_XID) {
 		CLIENT_SNAPSENT(clientdata) = 0;
 		CLIENT_XID(clientdata) = t->xid;
+        t->size += 1;
+        CHECK(
+            t->size <= t->max_size,
+            clientdata,
+            "SNAPSHOT: too many participants"
+            );
 	}
 
 	CHECK(
diff --git a/contrib/pg_xtm/dtmd/src/transaction.c b/contrib/pg_xtm/dtmd/src/transaction.c
@@ -28,6 +28,7 @@ void transaction_clear(Transaction *t) {
 
 	t->xid = INVALID_XID;
 	t->size = 0;
+	t->max_size = 0;
 	t->votes_for = 0;
 	t->votes_against = 0;
 	t->snapshots_count = 0;
