1 files changed, 35 insertions, 49 deletions

diff --git a/src/test/examples/testlibpq.c b/src/test/examples/testlibpq.c
index ca5ebbafba6..20dfb7220d9 100644
--- a/src/test/examples/testlibpq.c
+++ b/src/test/examples/testlibpq.c
@@ -1,10 +1,10 @@
 /*
  * testlibpq.c
- *		Test the C version of LIBPQ, the POSTGRES frontend library.
- *
  *
+ *		Test the C version of LIBPQ, the POSTGRES frontend library.
  */
 #include <stdio.h>
+#include <stdlib.h>
 #include "libpq-fe.h"
 
 static void
@@ -15,76 +15,66 @@ exit_nicely(PGconn *conn)
 }
 
 int
-main()
+main(int argc, char **argv)
 {
-	char	   *pghost,
-			   *pgport,
-			   *pgoptions,
-			   *pgtty;
-	char	   *dbName;
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
 	int			nFields;
 	int			i,
 				j;
 
-#ifdef DEBUG
-	FILE	   *debug;
-#endif   /* DEBUG */
-
-	PGconn	   *conn;
-	PGresult   *res;
-
 	/*
-	 * begin, by setting the parameters for a backend connection if the
-	 * parameters are null, then the system will try to use reasonable
-	 * defaults by looking up environment variables or, failing that,
-	 * using hardwired constants
+	 * If the user supplies a parameter on the command line, use it as
+	 * the conninfo string; otherwise default to setting dbname=template1
+	 * and using environment variables or defaults for all other connection
+	 * parameters.
 	 */
-	pghost = NULL;				/* host name of the backend server */
-	pgport = NULL;				/* port of the backend server */
-	pgoptions = NULL;			/* special options to start up the backend
-								 * server */
-	pgtty = NULL;				/* debugging tty for the backend server */
-	dbName = "template1";
-
-	/* make a connection to the database */
-	conn = PQsetdb(pghost, pgport, pgoptions, pgtty, dbName);
-
-	/* check to see that the backend connection was successfully made */
-	if (PQstatus(conn) == CONNECTION_BAD)
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = template1";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
 	{
-		fprintf(stderr, "Connection to database '%s' failed.\n", dbName);
+		fprintf(stderr, "Connection to database '%s' failed.\n", PQdb(conn));
 		fprintf(stderr, "%s", PQerrorMessage(conn));
 		exit_nicely(conn);
 	}
 
-#ifdef DEBUG
-	debug = fopen("/tmp/trace.out", "w");
-	PQtrace(conn, debug);
-#endif   /* DEBUG */
+	/*
+	 * Our test case here involves using a cursor, for which we must be
+	 * inside a transaction block.  We could do the whole thing with a
+	 * single PQexec() of "select * from pg_database", but that's too
+	 * trivial to make a good example.
+	 */
 
-	/* start a transaction block */
+	/* Start a transaction block */
 	res = PQexec(conn, "BEGIN");
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
 	{
-		fprintf(stderr, "BEGIN command failed\n");
+		fprintf(stderr, "BEGIN command failed: %s", PQerrorMessage(conn));
 		PQclear(res);
 		exit_nicely(conn);
 	}
 
 	/*
-	 * should PQclear PGresult whenever it is no longer needed to avoid
+	 * Should PQclear PGresult whenever it is no longer needed to avoid
 	 * memory leaks
 	 */
 	PQclear(res);
 
 	/*
-	 * fetch instances from the pg_database, the system catalog of
-	 * databases
+	 * Fetch rows from pg_database, the system catalog of databases
 	 */
 	res = PQexec(conn, "DECLARE myportal CURSOR FOR select * from pg_database");
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
 	{
-		fprintf(stderr, "DECLARE CURSOR command failed\n");
+		fprintf(stderr, "DECLARE CURSOR failed: %s", PQerrorMessage(conn));
 		PQclear(res);
 		exit_nicely(conn);
 	}
@@ -93,7 +83,7 @@ main()
 	res = PQexec(conn, "FETCH ALL in myportal");
 	if (PQresultStatus(res) != PGRES_TUPLES_OK)
 	{
-		fprintf(stderr, "FETCH ALL command didn't return tuples properly\n");
+		fprintf(stderr, "FETCH ALL failed: %s", PQerrorMessage(conn));
 		PQclear(res);
 		exit_nicely(conn);
 	}
@@ -104,7 +94,7 @@ main()
 		printf("%-15s", PQfname(res, i));
 	printf("\n\n");
 
-	/* next, print out the instances */
+	/* next, print out the rows */
 	for (i = 0; i < PQntuples(res); i++)
 	{
 		for (j = 0; j < nFields; j++)
@@ -114,7 +104,7 @@ main()
 
 	PQclear(res);
 
-	/* close the portal */
+	/* close the portal ... we don't bother to check for errors ... */
 	res = PQexec(conn, "CLOSE myportal");
 	PQclear(res);
 
@@ -125,9 +115,5 @@ main()
 	/* close the connection to the database and cleanup */
 	PQfinish(conn);
 
-#ifdef DEBUG
-	fclose(debug);
-#endif   /* DEBUG */
-
 	return 0;
 }