From f70fc781adf0833ecd148d672f22d6a1d860c365 Mon Sep 17 00:00:00 2001
From: Michael Banck <michael.banck@credativ.de>
Date: Thu, 31 Oct 2024 18:49:14 +0100
Subject: [PATCH v3 2/2] Add support for database service to psql prompt.

This adds a new psql variable SERVICE as well as the string '%s' for the
psql PROMPT, displaying the service (from PGSERVICEFILE) if so desired.
---
 doc/src/sgml/ref/psql-ref.sgml | 14 ++++++++++++++
 src/bin/psql/command.c         |  2 ++
 src/bin/psql/prompt.c          |  6 ++++++
 3 files changed, 22 insertions(+)

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index e42073ed74..6ba85d9acf 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -4380,6 +4380,15 @@ bar
         </listitem>
       </varlistentry>
 
+      <varlistentry id="app-psql-variables-service">
+        <term><varname>SERVICE</varname></term>
+        <listitem>
+        <para>
+        The service name, if applicable.
+        </para>
+        </listitem>
+      </varlistentry>
+
       <varlistentry id="app-psql-variables-shell-error">
        <term><varname>SHELL_ERROR</varname></term>
        <listitem>
@@ -4685,6 +4694,11 @@ testdb=&gt; <userinput>INSERT INTO my_table VALUES (:'content');</userinput>
          (tilde) if the database is your default database.</para></listitem>
       </varlistentry>
 
+      <varlistentry id="app-psql-prompting-s">
+        <term><literal>%s</literal></term>
+        <listitem><para>The name of the service entry.</para></listitem>
+      </varlistentry>
+
       <varlistentry id="app-psql-prompting-numbersign">
         <term><literal>%#</literal></term>
         <listitem>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 1f3cbb11f7..cd16f27947 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -4082,6 +4082,7 @@ SyncVariables(void)
 	pset.sversion = PQserverVersion(pset.db);
 
 	SetVariable(pset.vars, "DBNAME", PQdb(pset.db));
+	SetVariable(pset.vars, "SERVICE", PQservice(pset.db));
 	SetVariable(pset.vars, "USER", PQuser(pset.db));
 	SetVariable(pset.vars, "HOST", PQhost(pset.db));
 	SetVariable(pset.vars, "PORT", PQport(pset.db));
@@ -4115,6 +4116,7 @@ void
 UnsyncVariables(void)
 {
 	SetVariable(pset.vars, "DBNAME", NULL);
+	SetVariable(pset.vars, "SERVICE", NULL);
 	SetVariable(pset.vars, "USER", NULL);
 	SetVariable(pset.vars, "HOST", NULL);
 	SetVariable(pset.vars, "PORT", NULL);
diff --git a/src/bin/psql/prompt.c b/src/bin/psql/prompt.c
index 0d99d00ac9..3b3f079229 100644
--- a/src/bin/psql/prompt.c
+++ b/src/bin/psql/prompt.c
@@ -33,6 +33,7 @@
  * %p - backend pid
  * %> - database server port number
  * %n - database user name
+ * %s - service
  * %/ - current database
  * %~ - like %/ but "~" when database name equals user name
  * %w - whitespace of the same width as the most recent output of PROMPT1
@@ -246,6 +247,11 @@ get_prompt(promptStatus_t status, ConditionalStack cstack)
 						}
 					break;
 
+				case 's':
+					if (pset.db && PQservice(pset.db))
+						strlcpy(buf, PQservice(pset.db), sizeof(buf));
+					break;
+
 				case 'l':
 					snprintf(buf, sizeof(buf), UINT64_FORMAT, pset.stmt_lineno);
 					break;
-- 
2.39.5