Report the true database name on connection errors

alvherre · alvherre · commit bcae842b962a · 2021-01-26T16:42:13.000-03:00
When reporting connection errors, we might show a database name in the message that's not the one we actually tried to connect to, if the database was taken from libpq defaults instead of from user parameters. Fix such error messages to use PQdb(), which reports the correct name. (But, per commit 2930c05, make sure not to try to print NULL.) Apply to branches 9.5 through 13. Branch master has already been changed differently by commit 58cd8dc. Reported-by: Robert Haas <robertmhaas@gmail.com> Discussion: https://postgr.es/m/CA+TgmobssJ6rS22dspWnu-oDxXevGmhMD8VcRBjmj-b9UDqRjw@mail.gmail.com
diff --git a/contrib/oid2name/oid2name.c b/contrib/oid2name/oid2name.c
@@ -319,7 +319,7 @@ sql_conn(struct options * my_opts)
 	if (PQstatus(conn) == CONNECTION_BAD)
 	{
 		fprintf(stderr, "%s: could not connect to database %s: %s",
-				"oid2name", my_opts->dbname, PQerrorMessage(conn));
+				"oid2name", PQdb(conn) ? PQdb(conn) : "", PQerrorMessage(conn));
 		PQfinish(conn);
 		exit(1);
 	}
diff --git a/contrib/vacuumlo/vacuumlo.c b/contrib/vacuumlo/vacuumlo.c
@@ -124,7 +124,7 @@ vacuumlo(const char *database, const struct _param * param)
 	if (PQstatus(conn) == CONNECTION_BAD)
 	{
 		fprintf(stderr, "Connection to database \"%s\" failed:\n%s",
-				database, PQerrorMessage(conn));
+				PQdb(conn) ? PQdb(conn) : "", PQerrorMessage(conn));
 		PQfinish(conn);
 		return -1;
 	}
diff --git a/src/bin/pg_dump/pg_dumpall.c b/src/bin/pg_dump/pg_dumpall.c
@@ -2088,7 +2088,7 @@ connectDatabase(const char *dbname, const char *connection_string,
 		{
 			fprintf(stderr,
 					_("%s: could not connect to database \"%s\": %s"),
-					progname, dbname, PQerrorMessage(conn));
+					progname, PQdb(conn) ? PQdb(conn) : "", PQerrorMessage(conn));
 			exit_nicely(1);
 		}
 		else
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
@@ -828,7 +828,7 @@ doConnect(void)
 	if (PQstatus(conn) == CONNECTION_BAD)
 	{
 		fprintf(stderr, "connection to database \"%s\" failed:\n%s",
-				dbName, PQerrorMessage(conn));
+				PQdb(conn), PQerrorMessage(conn));
 		PQfinish(conn);
 		return NULL;
 	}
@@ -3913,7 +3913,8 @@ main(int argc, char **argv)
 
 	if (PQstatus(con) == CONNECTION_BAD)
 	{
-		fprintf(stderr, "connection to database \"%s\" failed\n", dbName);
+		fprintf(stderr, "connection to database \"%s\" failed\n",
+				PQdb(con) ? PQdb(con) : "");
 		fprintf(stderr, "%s", PQerrorMessage(con));
 		exit(1);
 	}

Original file line number	Diff line number	Diff line change
`@@ -319,7 +319,7 @@ sql_conn(struct options * my_opts)`
`319`	`319`	`if (PQstatus(conn) == CONNECTION_BAD)`
`320`	`320`	`{`
`321`	`321`	`fprintf(stderr, "%s: could not connect to database %s: %s",`
`322`		`- "oid2name", my_opts->dbname, PQerrorMessage(conn));`
	`322`	`+ "oid2name", PQdb(conn) ? PQdb(conn) : "", PQerrorMessage(conn));`
`323`	`323`	`PQfinish(conn);`
`324`	`324`	`exit(1);`
`325`	`325`	`}`
Original file line number	Diff line number	Diff line change
`@@ -124,7 +124,7 @@ vacuumlo(const char database, const struct _param param)`
`124`	`124`	`if (PQstatus(conn) == CONNECTION_BAD)`
`125`	`125`	`{`
`126`	`126`	`fprintf(stderr, "Connection to database \"%s\" failed:\n%s",`
`127`		`- database, PQerrorMessage(conn));`
	`127`	`+ PQdb(conn) ? PQdb(conn) : "", PQerrorMessage(conn));`
`128`	`128`	`PQfinish(conn);`
`129`	`129`	`return -1;`
`130`	`130`	`}`
Original file line number	Diff line number	Diff line change
`@@ -2088,7 +2088,7 @@ connectDatabase(const char dbname, const char connection_string,`
`2088`	`2088`	`{`
`2089`	`2089`	`fprintf(stderr,`
`2090`	`2090`	`_("%s: could not connect to database \"%s\": %s"),`
`2091`		`- progname, dbname, PQerrorMessage(conn));`
	`2091`	`+ progname, PQdb(conn) ? PQdb(conn) : "", PQerrorMessage(conn));`
`2092`	`2092`	`exit_nicely(1);`
`2093`	`2093`	`}`
`2094`	`2094`	`else`
Original file line number	Diff line number	Diff line change
`@@ -828,7 +828,7 @@ doConnect(void)`
`828`	`828`	`if (PQstatus(conn) == CONNECTION_BAD)`
`829`	`829`	`{`
`830`	`830`	`fprintf(stderr, "connection to database \"%s\" failed:\n%s",`
`831`		`- dbName, PQerrorMessage(conn));`
	`831`	`+ PQdb(conn), PQerrorMessage(conn));`
`832`	`832`	`PQfinish(conn);`
`833`	`833`	`return NULL;`
`834`	`834`	`}`
`@@ -3913,7 +3913,8 @@ main(int argc, char **argv)`
`3913`	`3913`
`3914`	`3914`	`if (PQstatus(con) == CONNECTION_BAD)`
`3915`	`3915`	`{`
`3916`		`- fprintf(stderr, "connection to database \"%s\" failed\n", dbName);`
	`3916`	`+ fprintf(stderr, "connection to database \"%s\" failed\n",`
	`3917`	`+ PQdb(con) ? PQdb(con) : "");`
`3917`	`3918`	`fprintf(stderr, "%s", PQerrorMessage(con));`
`3918`	`3919`	`exit(1);`
`3919`	`3920`	`}`