Implement an example application for libdtm.

kvap · kvap · commit 0582c5d115e9 · 2015-09-09T14:24:53.000+03:00
diff --git a/contrib/pg_xtm/dtmd/include/clogfile.h b/contrib/pg_xtm/dtmd/include/clogfile.h
@@ -11,7 +11,7 @@
 #define BITS_PER_COMMIT 2
 #define COMMIT_MASK ((1 << BITS_PER_COMMIT) - 1)
 #define COMMITS_PER_BYTE 4
-#define COMMITS_PER_FILE 1024 // 0x100000000
+#define COMMITS_PER_FILE 0x100000000
 #define BYTES_PER_FILE ((COMMITS_PER_FILE) / (COMMITS_PER_BYTE))
 #define XID_TO_FILEID(XID) ((XID) / (COMMITS_PER_FILE))
 #define XID_TO_OFFSET(XID) (((XID) % (COMMITS_PER_FILE)) / (COMMITS_PER_BYTE))
diff --git a/contrib/pg_xtm/dtmd/src/main.c b/contrib/pg_xtm/dtmd/src/main.c
@@ -308,6 +308,7 @@ static char *onsnapshot(void *client, cmd_t *cmd) {
 	}
 	assert(t->sent_seqno < t->snapshot.seqno);
 
+	t->sent_seqno++;
 	return snapshot_serialize(&t->snapshot);
 }
 
diff --git a/contrib/pg_xtm/dtmd/src/transaction.c b/contrib/pg_xtm/dtmd/src/transaction.c
@@ -38,7 +38,6 @@ bool global_transaction_mark(clog_t clg, GlobalTransaction *gt, int status) {
 		Transaction *t = gt->participants + node;
 		if (t->active) {
 			assert(t->node == node);
-			assert(t->vote == POSITIVE);
 			if (!clog_write(clg, MUX_XID(node, t->xid), status)) {
 				shout("clog write failed");
 				return false;
diff --git a/contrib/pg_xtm/libdtm/src/example.c b/contrib/pg_xtm/libdtm/src/example.c
@@ -3,20 +3,130 @@
 
 #include "libdtm.h"
 
+#define NODES 5
+
+void start_transaction(DTMConn conn, TransactionId base) {
+	GlobalTransactionId gtid;
+	gtid.nNodes = NODES;
+	gtid.xids = malloc(sizeof(TransactionId) * gtid.nNodes);
+	gtid.nodes = malloc(sizeof(NodeId) * gtid.nNodes);
+
+	int n;
+	for (n = 0; n < gtid.nNodes; n++) {
+		gtid.xids[n] = base + n;
+		gtid.nodes[n] = n;
+	}
+
+	if (!DtmGlobalStartTransaction(conn, &gtid)) {
+		fprintf(stdout, "global transaction not started\n");
+		exit(EXIT_FAILURE);
+	}
+	fprintf(stdout, "global transaction started\n");
+
+	free(gtid.xids);
+	free(gtid.nodes);
+}
+
+void commit_transaction(DTMConn conn, TransactionId base) {
+	int n;
+	for (n = 0; n < NODES; n++) {
+		if (!DtmGlobalSetTransStatus(conn, n, base + n, TRANSACTION_STATUS_COMMITTED)) {
+			fprintf(stdout, "global transaction not committed\n");
+			exit(EXIT_FAILURE);
+		}
+	}
+	fprintf(stdout, "global transaction committed\n");
+}
+
+void abort_transaction(DTMConn conn, TransactionId base) {
+	if (!DtmGlobalSetTransStatus(conn, 0, base + 0, TRANSACTION_STATUS_ABORTED)) {
+		fprintf(stdout, "global transaction not aborted\n");
+		exit(EXIT_FAILURE);
+	}
+	fprintf(stdout, "global transaction aborted\n");
+}
+
+void show_snapshots(DTMConn conn, TransactionId base) {
+	int i, n;
+	for (n = 0; n < NODES; n++) {
+		Snapshot s = malloc(sizeof(SnapshotData));
+		s->xip = NULL;
+
+		if (!DtmGlobalGetSnapshot(conn, n, base + n, s)) {
+			fprintf(stdout, "failed to get a snapshot[%d]\n", n);
+			exit(EXIT_FAILURE);
+		}
+		fprintf(stdout, "snapshot[%d, %#x]: xmin = %#x, xmax = %#x, active =", n, base + n, s->xmin, s->xmax);
+		for (i = 0; i < s->xcnt; i++) {
+			fprintf(stdout, " %#x", s->xip[i]);
+		}
+		fprintf(stdout, "\n");
+
+		free(s->xip);
+		free(s);
+	}
+}
+
+void show_status(DTMConn conn, TransactionId base) {
+	int n;
+	for (n = 0; n < NODES; n++) {
+		XidStatus s = DtmGlobalGetTransStatus(conn, n, base + n);
+		if (s == -1) {
+			fprintf(stdout, "failed to get transaction status [%d, %#x]\n", n, base + n);
+			exit(EXIT_FAILURE);
+		}
+		fprintf(stdout, "status[%d, %#x]: ", n, base + n);
+		switch (s) {
+			case TRANSACTION_STATUS_COMMITTED:
+				fprintf(stdout, "committed\n");
+				break;
+			case TRANSACTION_STATUS_ABORTED:
+				fprintf(stdout, "aborted\n");
+				break;
+			case TRANSACTION_STATUS_IN_PROGRESS:
+				fprintf(stdout, "in progress\n");
+				break;
+			default:
+				fprintf(stdout, "(error)\n");
+				break;
+		}
+	}
+}
+
 int main() {
 	DTMConn conn = DtmConnect("localhost", 5431);
 	if (!conn) {
 		fprintf(stderr, "failed to connect to dtmd\n");
 		exit(1);
 	}
 
-	xid_t xid = 0xdeadbeefcafebabe;
-	Snapshot s = malloc(sizeof(SnapshotData));
-	
-	DtmGlobalGetSnapshot(conn, 0, xid, s);
-	fprintf(stdout, "snapshot is %d xids wide\n", s->xcnt);
+	TransactionId base0 = 0xdeadbeef;
+	TransactionId base1 = base0 + NODES;
+	TransactionId base2 = base1 + NODES;
 
-	DtmDisconnect(conn);
+	start_transaction(conn, base0);
+	show_snapshots(conn, base0);
+
+	start_transaction(conn, base1);
+	show_snapshots(conn, base0);
+	show_snapshots(conn, base1);
+
+	start_transaction(conn, base2);
+	show_snapshots(conn, base0);
+	show_snapshots(conn, base1);
+	show_snapshots(conn, base2);
+
+	commit_transaction(conn, base0);
+	show_snapshots(conn, base1);
+	show_snapshots(conn, base2);
 
-	return 0;
+	abort_transaction(conn, base1);
+	show_snapshots(conn, base2);
+
+	show_status(conn, base0);
+	show_status(conn, base1);
+	show_status(conn, base2);
+
+	DtmDisconnect(conn);
+	return EXIT_SUCCESS;
 }
diff --git a/contrib/pg_xtm/libdtm/src/libdtm.c b/contrib/pg_xtm/libdtm/src/libdtm.c
@@ -0,0 +1 @@
+../../libdtm.c
diff --git a/contrib/pg_xtm/libdtm/src/libdtm.h b/contrib/pg_xtm/libdtm/src/libdtm.h
@@ -0,0 +1 @@
+../../libdtm.h

Original file line number	Diff line number	Diff line change
`@@ -308,6 +308,7 @@ static char onsnapshot(void client, cmd_t *cmd) {`
`308`	`308`	`}`
`309`	`309`	`assert(t->sent_seqno < t->snapshot.seqno);`
`310`	`310`
	`311`	`+ t->sent_seqno++;`
`311`	`312`	`return snapshot_serialize(&t->snapshot);`
`312`	`313`	`}`
`313`	`314`