From 060ff57642fc74f320761586e244151c04e63755 Mon Sep 17 00:00:00 2001
From: David Bremner <david@tethera.net>
Date: Thu, 9 Sep 2021 09:51:03 -0300
Subject: [PATCH] lib: use 'localhost' rather than fqdn for default mail
 address.

As discussed in the thread starting at [1], the fully qualified domain
name is a bit tricky to get reproducibly, might reveal information
people prefer to keep private, and somewhat unlikely to provide
reliable mail routing.

The new approach of $current_username@localhost is better for the
first two considerations, and probably at least as good as a test mail
address.

[1]: id:87sfyibqhj.fsf@tethera.net
---
 lib/config.cc          | 16 +---------------
 test/T590-libconfig.sh | 10 ++++------
 2 files changed, 5 insertions(+), 21 deletions(-)

diff --git a/lib/config.cc b/lib/config.cc
index 7ecc3c7b..8775b00a 100644
--- a/lib/config.cc
+++ b/lib/config.cc
@@ -543,25 +543,11 @@ _get_username_from_passwd_file (void *ctx)
 static const char *
 _get_email_from_passwd_file (void *ctx)
 {
-
-    char hostname[256];
-    struct hostent *hostent;
-    const char *domainname;
     char *email;
 
     char *username = _get_username_from_passwd_file (ctx);
 
-    gethostname (hostname, 256);
-    hostname[255] = '\0';
-
-    hostent = gethostbyname (hostname);
-    if (hostent && (domainname = strchr (hostent->h_name, '.')))
-	domainname += 1;
-    else
-	domainname = "(none)";
-
-    email = talloc_asprintf (ctx, "%s@%s.%s",
-			     username, hostname, domainname);
+    email = talloc_asprintf (ctx, "%s@localhost", username);
 
     talloc_free (username);
     return email;
diff --git a/test/T590-libconfig.sh b/test/T590-libconfig.sh
index 41f67bae..59b82a6f 100755
--- a/test/T590-libconfig.sh
+++ b/test/T590-libconfig.sh
@@ -12,12 +12,10 @@ import os, sys, pwd, socket
 pw = pwd.getpwuid(os.getuid())
 user = pw.pw_name
 name = pw.pw_gecos.partition(",")[0]
-fqdn = socket.getaddrinfo(socket.gethostname(), 0, 0,
-                          socket.SOCK_STREAM, 0, socket.AI_CANONNAME)[0][3]
+
 for l in sys.stdin:
     if l[:4] == "08: ":
-        l = l.replace(user, "USERNAME", 1).replace("@" + fqdn, "@FQDN", 1)
-        l = l.replace(".(none)", "", 1).replace(".localdomain", "", 1)
+        l = l.replace(user, "USERNAME", 1)
     elif l[:4] == "10: ":
         l = l.replace("'" + name, "'USER_FULL_NAME", 1)
     sys.stdout.write(l)
@@ -416,7 +414,7 @@ cat <<'EOF' >EXPECTED
 05: 'unread;inbox'
 06: ''
 07: 'true'
-08: 'USERNAME@FQDN'
+08: 'USERNAME@localhost'
 09: 'NULL'
 10: 'USER_FULL_NAME'
 11: '8000'
@@ -761,7 +759,7 @@ cat <<'EOF' >EXPECTED
 05: 'unread;inbox'
 06: ''
 07: 'true'
-08: 'USERNAME@FQDN'
+08: 'USERNAME@localhost'
 09: 'NULL'
 10: 'USER_FULL_NAME'
 11: '8000'