From: Karel Zak <kzak@redhat.com>
Date: Thu, 28 Jun 2007 23:50:50 +0000 (+0200)
Subject: agetty: add 'O' escape code to display domain name
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e61e66bd95e20d1a9a101c5a2efb4c638ca732f1;p=util-linux

agetty: add 'O' escape code to display domain name

This patch add a new 'O' escape code to display domain name
by issue-file (/etc/issue) output.

(Based on an Gentoo patch.)

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/login-utils/agetty.8 b/login-utils/agetty.8
index 69be5f2b..dc18691f 100644
--- a/login-utils/agetty.8
+++ b/login-utils/agetty.8
@@ -217,7 +217,10 @@ n
 Insert the nodename of the machine, also known as the hostname.
 .TP
 o
-Insert the domainname of the machine.
+Insert the NIS domainname of the machine.
+.TP
+O
+Insert the DNS domainname of the machine.
 .TP
 r
 Insert the release number of the OS, eg. 1.1.9.
diff --git a/login-utils/agetty.c b/login-utils/agetty.c
index eb9fab56..c8271039 100644
--- a/login-utils/agetty.c
+++ b/login-utils/agetty.c
@@ -30,6 +30,9 @@
 #include <getopt.h>
 #include <time.h>
 #include <sys/file.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
 #include "xstrncpy.h"
 #include "nls.h"
 
@@ -120,6 +123,15 @@
   */
 #ifndef BUFSIZ
 #define	BUFSIZ		1024
+#endif
+
+/* set a maximum length for the hostname,  */
+#ifdef HOST_NAME_MAX
+# define HOSTNAME_LENGTH HOST_NAME_MAX		/* defined by POSIX.1 */
+#elif defined(MAXHOSTNAMELEN)
+# define HOSTNAME_LENGTH MAXHOSTNAMELEN		/* implemented in current Unix-versions */
+#else
+# define HOSTNAME_LENGTH 255
 #endif
 
  /*
@@ -879,6 +891,31 @@ do_prompt(op, tp)
 		   }
 		  break;
 
+		  case 'O':
+		   {
+			char *dom = "unknown_domain";
+			char host[HOST_NAME_MAX + 1];
+			struct addrinfo hints, *info = NULL;
+
+			memset(&hints, 0, sizeof(hints));
+			hints.ai_flags = AI_CANONNAME;
+
+			if (gethostname(host, sizeof(host)) ||
+			    getaddrinfo(host, NULL, &hints, &info) ||
+			    info == NULL)
+				fputs(dom, stdout);
+			else {
+				char *canon;
+
+				if (info->ai_canonname &&
+				    (canon = strchr(info->ai_canonname, '.')))
+					dom = canon + 1;
+				fputs(dom, stdout);
+				freeaddrinfo(info);
+			}
+		   }
+		  break;
+
 		  case 'd':
 		  case 't':
 		    {