(c-macro-preprocessor): Define a preprocessor name

which is valid on MS-DOS.

(c-macro-expansion): Do not rely on ``/tmp/'' being present; use
environment variables as alternatives (MSDOS).  Use
`shell-file-name' rather than ``sh''.  Redirect `stderr' with
`call-process-region' option, not from the shell.  Handle shells
which don't return exit code from `cpp' (MSDOS).  Put messages
from `cpp' inside a comment, to avoid messing up syntax highlighting.

diff --git a/lisp/progmodes/cmacexp.el b/lisp/progmodes/cmacexp.el
index 0eaac943382bb5db0e3fa9dfec5f1b85e86225ec..0a7734041869f738d30796290206fd84ee13caf2 100644 (file)
--- a/lisp/progmodes/cmacexp.el
+++ b/lisp/progmodes/cmacexp.el
@@ -3,7 +3,7 @@
 ;; Copyright (C) 1992, 1994 Free Software Foundation, Inc.
 
 ;; Author: Francesco Potorti` <pot@cnuce.cnr.it>
-;; Version: $Id: cmacexp.el,v 1.20 1995/10/26 03:14:40 rms Exp erik $
+;; Version: $Id: cmacexp.el,v 1.21 1996/01/14 07:34:30 erik Exp rms $
 ;; Adapted-By: ESR
 ;; Keywords: c
 
@@ -96,7 +96,9 @@
 (defvar c-macro-prompt-flag nil
   "*Non-nil makes `c-macro-expand' prompt for preprocessor arguments.")
 
-(defvar c-macro-preprocessor "/lib/cpp -C"
+(defvar c-macro-preprocessor
+  ;; Cannot rely on standard directory on MS-DOS to find CPP.
+  (if (eq system-type 'ms-dos) "cpp -C" "/lib/cpp -C")
   "The preprocessor used by the cmacexp package.
 
 If you change this, be sure to preserve the `-C' (don't strip comments)
@@ -244,7 +246,8 @@ Optional arg DISPLAY non-nil means show messages in the echo area."
        (startstat ())
        (startmarker "")
        (exit-status 0)
-       (tempname (make-temp-name "/tmp/")))
+       (tempname (make-temp-name (or (getenv "TMPDIR") (getenv "TEMP")
+                                     (getenv "TMP") "/tmp/"))))
     (unwind-protect
        (save-excursion
          (save-restriction
@@ -306,8 +309,10 @@ Optional arg DISPLAY non-nil means show messages in the echo area."
          ;; Call the preprocessor.
          (if display (message mymsg))
          (setq exit-status
-               (call-process-region 1 (point-max) "sh" t t nil "-c"
-                                    (concat cppcommand " 2>" tempname)))
+               (call-process-region 1 (point-max)
+                                    shell-file-name
+                                    t (list t tempname) nil "-c"
+                                    cppcommand))
          (if display (message (concat mymsg "done")))
          (if (= (buffer-size) 0)
              ;; Empty output is normal after a fatal error.
@@ -326,13 +331,25 @@ Optional arg DISPLAY non-nil means show messages in the echo area."
              (delete-region beg (point))))
 
          ;; If CPP got errors, show them at the beginning.
-         (or (eq exit-status 0)
+         ;; MS-DOS shells don't return the exit code of their children.
+         ;; Look at the size of the error message file instead, but
+         ;; don't punish those MS-DOS users who have a shell that does
+         ;; return an error code.
+         (or (and (or (not (boundp 'msdos-shells))
+                      (not (member (file-name-nondirectory shell-file-name)
+                                   msdos-shells)))
+                  (eq exit-status 0))
+             (zerop (nth 7 (file-attributes (expand-file-name tempname))))
              (progn
                (goto-char (point-min))
-               (insert (format "Preprocessor terminated with status %s\n"
-                               exit-status))
-               (insert-file-contents tempname)
-               (insert "\n")))
+               ;; Put the messages inside a comment, so they won't get in
+               ;; the way of font-lock, highlighting etc.
+               (insert
+                (format "/* Preprocessor terminated with status %s\n\n   Messages from `%s\':\n\n"
+                        exit-status cppcommand))
+               (goto-char (+ (point)
+                             (nth 1 (insert-file-contents tempname))))
+               (insert "\n\n*/\n")))
          (delete-file tempname)
 
          ;; Compute the return value, keeping in account the space