svn commit: r299035 - head/bin/sh

[Eric van Gyzen]

Author: vangyzen
Date: Wed May  4 02:06:46 2016
New Revision: 299035
URL: https://svnweb.freebsd.org/changeset/base/299035

Log:
  sh: Handle empty hostname and $PWD when building prompt
  
  If the hostname is empty and \h is used in $PS1,
  the remainder of the prompt following \h will be empty.
  Likewise for $PWD and \w.  Fix it.
  
  Reviewed by:	jilles
  MFC after:	1 week
  Sponsored by:	Dell Inc.
  Differential Revision:	https://reviews.freebsd.org/D6188

Modified:
  head/bin/sh/parser.c

Modified: head/bin/sh/parser.c
==============================================================================
--- head/bin/sh/parser.c	Wed May  4 01:56:37 2016	(r299034)
+++ head/bin/sh/parser.c	Wed May  4 02:06:46 2016	(r299035)
@@ -2014,8 +2014,9 @@ getprompt(void *unused __unused)
 				gethostname(&ps[i], PROMPTLEN - i);
 				/* Skip to end of hostname. */
 				trim = (*fmt == 'h') ? '.' : '\0';
-				while ((ps[i+1] != '\0') && (ps[i+1] != trim))
+				while ((ps[i] != '\0') && (ps[i] != trim))
 					i++;
+				--i;
 				break;
 
 				/*
@@ -2027,7 +2028,7 @@ getprompt(void *unused __unused)
 			case 'W':
 			case 'w':
 				pwd = lookupvar("PWD");
-				if (pwd == NULL)
+				if (pwd == NULL || *pwd == '\0')
 					pwd = "?";
 				if (*fmt == 'W' &&
 				    *pwd == '/' && pwd[1] != '\0')