summaryrefslogtreecommitdiff
path: root/vms/make-mms-derivative.el
blob: 4d226374cfd0f1b021cf536c780c92aa4c196b2f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
;;; make-mms-derivative.el --- framework to do horrible things for VMS support

;; Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.

;; Author: Thien-Thi Nguyen <ttn@gnu.org>
;; Keywords: maint build vms mms makefile levitte autoconf war-is-a-lose

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;; Under VMS the standard make-like program is called MMS, which looks
;; for an input file in the default directory named DESCRIP.MMS and runs
;; the DCL command rules therein.  As of 2005, the build process
;; requires a hand translation of the Makefile.in and Emacs-specific
;; methodology to DCL and TPU commands, so to alleviate this pain, we
;; provide `make-mms-derivative', which given a source FILENAME, inserts
;; the file contents in a new buffer and loads FILENAME-2mms.  The lisp
;; code in the -2mms file can (do whatever -- it's emacs -- and), as
;; long as it arranges to write out the modified buffer after loading by
;; specifying, on a line of its own, the directive:
;;
;;  :output RELATIVE-OUTPUT
;;
;; where RELATIVE-OUTPUT is a filename (a string) relative to FILENAME's
;; directory, typically something simple like "descrip.mms_in_in".  Only
;; the first :output directive is recognized.
;;
;; The only other special directive at this time has the form:
;;
;;  :gigo NAME
;;  ;;blah blah blah
;;  ;;(more text here)
;;
;; NAME is anything distinguishable w/ `eq' (number, symbol or keyword).
;; This associates NAME with the block of text starting immediately below
;; the :gigo directive and ending at the first line that does not begin
;; with two semicolons (which are stripped from each line in the block).
;; To insert this block of text, pass NAME to `make-mms-derivative-gigo'.
;;
;; Directives are scanned before normal evaluation, so their placement
;; in the file is not important.  During loading, plain strings are
;; displayed in the echo area, prefixed with the current line number.
;;
;; Over the long run, the convenience functions provided (see source)
;; will be augmented by factoring maximally the -2mms files, squeezing
;; as much algorithm out of those nasty heuristics as possible.  What
;; makes them nasty is not that they rely on the conventions of the
;; Emacs makefiles; that's no big deal.  What makes them nasty is that
;; they rely on the conventions of separately maintained tools (namely
;; Autoconf for VMS and GNU Autoconf), and the separation of conventions
;; is how people drift apart, dragging their software behind
;; mercilessly.
;;
;; In general, codified thought w/o self-synchronization is doomed.
;; That a generation would eat its young (most discriminatingly, even)
;; is no reason GNU cannot build around such woe.

;;; Code:

(defvar make-mms-derivative-data nil
  "Plist of data specific to `make-mms-derivative'.")

(defun make-mms-derivative-data (key &optional newval)
  (if newval (setq make-mms-derivative-data
		   (plist-put make-mms-derivative-data key newval))
    (plist-get make-mms-derivative-data key)))

(defun make-mms-derivative-gigo (name)
  "Insert the text associated with :gigo NAME."
  (insert (cdr (assq name (make-mms-derivative-data :gigo)))))

(defun make-mms-derivative (filename)
  "Take FILENAME contents, load FILENAME-2mms, and write out the result.
The output file is specified by the :output directive in FILENAME-2mms.
See commentary of make-mms-derivative.el for full documentation."
  (interactive "fSource File: ")
  (let* ((todo (let ((fn (concat filename "-2mms")))
		 (unless (file-exists-p fn)
		   (error "Could not find %s" fn))
		 (set-buffer (get-buffer-create " *make-mms-derivative todo*"))
		 (insert-file-contents fn)
		 (current-buffer)))
	 (deriv (get-buffer-create (format "*mms-derivative: %s"
					   (file-relative-name filename))))
	 output gigo form)
    (set-buffer todo)
    (re-search-forward "^:output")
    (setq output (expand-file-name (read (current-buffer))
				   (file-name-directory filename)))
    (goto-char (point-min))
    (while (re-search-forward "^:gigo" (point-max) t)
      (let ((name (read (current-buffer)))
	    (p (progn (forward-line 1) (point))))
	(while (looking-at ";;")
	  (delete-char 2)
	  (forward-line 1))
	(setq gigo (cons (cons name (buffer-substring p (point))) gigo))
	(delete-region p (point))))
    (message "Munging...")
    (switch-to-buffer deriv)
    (erase-buffer)
    (insert-file-contents filename)
    (set (make-local-variable 'make-mms-derivative-data)
	 (list :gigo gigo))
    (set-buffer todo)
    (goto-char (point-min))
    (while (condition-case nil
	       (setq form (read (current-buffer)))
	     (end-of-file nil))
      (if (stringp form)
	  (message "%d: %s" (count-lines (point-min) (point)) form)
	(save-excursion
	  (set-buffer deriv)
	  (eval form))))
    (set-buffer deriv)
    (message "Munging...done")
    (write-file output)
    (kill-buffer todo)
    (kill-buffer deriv)))

(provide 'make-mms-derivative)

;;; arch-tag: a5b08625-3952-4053-be16-296220e27bb0
;;; make-mms-derivative.el ends here