From dcca1b5b0ef4d84460e1dfb583f1085cc1ce5b9c Mon Sep 17 00:00:00 2001
From: Hartmut Becker <becker.ismaning@freenet.de>
Date: Wed, 3 Sep 2014 23:39:25 +0200
Subject: [PATCH] Enhance VMS exporting make environment variables.

* config.h-vms.template: add feature macro USE_DCL_COM_FILE to always
write a DCL command file, enabled by default.
* vmsjobs.c: with USE_DCL_COM_FILE enabled write make variables as DCL
symbol assignments into the command file.  This enables printing
directory and make level info for recursive use of make. This also
enables forced DCL symbol substitution in the actions.
---
 config.h-vms.template | 10 +++++++++-
 vmsjobs.c             | 29 ++++++++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/config.h-vms.template b/config.h-vms.template
index eefc2993..71fe269f 100644
--- a/config.h-vms.template
+++ b/config.h-vms.template
@@ -1,6 +1,6 @@
 /* config.h-vms. Generated by hand by Klaus Kämpf <kkaempf@rmi.de>      -*-C-*-
 
-Copyright (C) 1996-2013 Free Software Foundation, Inc.
+Copyright (C) 1996-2014 Free Software Foundation, Inc.
 This file is part of GNU Make.
 
 GNU Make is free software; you can redistribute it and/or modify it under the
@@ -414,5 +414,13 @@ this program.  If not, see <http://www.gnu.org/licenses/>.  */
 /* Output sync sypport */
 #define NO_OUTPUT_SYNC
 
+/* Define to 1 to write even short single-line actions into a VMS/DCL command
+   file; this also enables exporting make environment variables into the
+   (sub-)process, which executes the action.
+   The usual make rules apply whether a shell variable - here a DCL symbol or
+   VMS logical [see CRTL getenv()] - is added to the make environment and
+   is exported. */
+#define USE_DCL_COM_FILE 1
+
 /* Build host information. */
 #define MAKE_HOST "VMS"
diff --git a/vmsjobs.c b/vmsjobs.c
index e81d0894..c49d3b9f 100644
--- a/vmsjobs.c
+++ b/vmsjobs.c
@@ -613,14 +613,24 @@ child_execute_job (char *argv, struct child *child)
 
       cmd = tmp_cmd;
     }
+
+#ifdef USE_DCL_COM_FILE
+  /* Enforce the creation of a command file.
+     Then all the make environment variables are written as DCL symbol
+     assignments into the command file as well, so that they are visible
+     in the sub-process but do not affect the current process.
+     Further, this way DCL reads the input stream and therefore does
+     'forced' symbol substitution, which it doesn't do for one-liners when
+     they are 'lib$spawn'ed. */
+#else
   /* Create a *.com file if either the command is too long for
      lib$spawn, or the command contains a newline, or if redirection
      is desired. Forcing commands with newlines into DCLs allows to
      store search lists on user mode logicals.  */
-
   if (strlen (cmd) > MAXCMDLEN
       || (have_redirection != 0)
       || (have_newline != 0))
+#endif
     {
       FILE *outfile;
       char c;
@@ -686,6 +696,23 @@ child_execute_job (char *argv, struct child *child)
             DB (DB_JOBS, (_("Redirected output to %s\n"), ofile));
             ofiledsc.dsc$w_length = 0;
           }
+#ifdef USE_DCL_COM_FILE
+      /* Export the child environment into DCL symbols */
+      if (child->environment != 0)
+        {
+          char **ep = child->environment;
+          char *valstr;
+          while (*ep != 0)
+            {
+              valstr = strchr(*ep, '=');
+              if (valstr == NULL)
+                continue;
+              fprintf(outfile, "$ %.*s=\"%s\"\n", valstr - *ep, *ep,
+                  valstr + 1);
+              ep++;
+            }
+        }
+#endif
       fprintf (outfile, "$ %.*s_ = f$verify(%.*s_1)\n", tmpstrlen, tmpstr, tmpstrlen, tmpstr);
       p = sep = q = cmd;
       for (c = '\n'; c; c = *q++)