libpq: Add service name to PGconn and PQservice()

michaelpq · michaelpq · commit 4b99fed7541e · 2024-12-18T14:53:42.000+09:00
This commit adds one field to PGconn for the database service name (if any), with PQservice() as routine to retrieve it. Like the other routines of this area, NULL is returned as result if the connection is NULL. A follow-up patch will make use of this feature to be able to display the service name in the psql prompt. Author: Michael Banck Reviewed-by: Greg Sabino Mullane Discusion: https://postgr.es/m/6723c612.050a0220.1567f4.b94a@mx.google.com
diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
@@ -2530,6 +2530,26 @@ char *PQport(const PGconn *conn);
      </listitem>
     </varlistentry>
 
+    <varlistentry id="libpq-PQservice">
+     <term><function>PQservice</function><indexterm><primary>PQservice</primary></indexterm></term>
+
+     <listitem>
+      <para>
+       Returns the service of the active connection.
+
+<synopsis>
+char *PQservice(const PGconn *conn);
+</synopsis>
+      </para>
+
+      <para>
+       <xref linkend="libpq-PQservice"/> returns <symbol>NULL</symbol> if the
+       <parameter>conn</parameter> argument is <symbol>NULL</symbol>.
+       Otherwise, if there was no service provided, it returns an empty string.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry id="libpq-PQtty">
      <term><function>PQtty</function><indexterm><primary>PQtty</primary></indexterm></term>
 
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
@@ -205,3 +205,4 @@ PQcancelFinish            202
 PQsocketPoll              203
 PQsetChunkedRowsMode      204
 PQgetCurrentTimeUSec      205
+PQservice                 206
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
@@ -190,7 +190,8 @@ typedef struct _internalPQconninfoOption
 
 static const internalPQconninfoOption PQconninfoOptions[] = {
 	{"service", "PGSERVICE", NULL, NULL,
-	"Database-Service", "", 20, -1},
+		"Database-Service", "", 20,
+	offsetof(struct pg_conn, pgservice)},
 
 	{"user", "PGUSER", NULL, NULL,
 		"Database-User", "", 20,
@@ -7040,6 +7041,14 @@ PQdb(const PGconn *conn)
 	return conn->dbName;
 }
 
+char *
+PQservice(const PGconn *conn)
+{
+	if (!conn)
+		return NULL;
+	return conn->pgservice;
+}
+
 char *
 PQuser(const PGconn *conn)
 {
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
@@ -385,6 +385,7 @@ extern int	PQrequestCancel(PGconn *conn);
 
 /* Accessor functions for PGconn objects */
 extern char *PQdb(const PGconn *conn);
+extern char *PQservice(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
@@ -394,6 +394,7 @@ struct pg_conn
 	char	   *fbappname;		/* fallback application name */
 	char	   *dbName;			/* database name */
 	char	   *replication;	/* connect as the replication standby? */
+	char	   *pgservice;		/* Postgres service, if any */
 	char	   *pguser;			/* Postgres username and password, if any */
 	char	   *pgpass;
 	char	   *pgpassfile;		/* path to a file containing password(s) */
