-;;; cmacexp.el --- C macro expansion
+;;; cmacexp.el --- expand C macros in a region
-;; Copyright (C) 1988 Free Software Foundation, Inc.
+;; Copyright (C) 1992, 1994, 1996 Free Software Foundation, Inc.
-;; Maintainer: FSF
+;; Author: Francesco Potorti` <pot@cnuce.cnr.it>
+;; Adapted-By: ESR
;; Keywords: c
;; This file is part of GNU Emacs.
;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
-
-;;; Code:
-
-(defvar c-macro-preprocessor "/lib/cpp"
- "*Command to be used for C preprocessing.")
-
-(defvar c-macro-options nil
- "*List of options to use in C preprocessing.
-Each string in the list becomes a separate argument to the preprocessor.
-These arguments precede the filename.
-Use the `-I' option here to specify directories for header files.")
-
-(defun c-macro-expand (beg end)
- "Display the result of expanding all C macros occurring in the region.
-The expansion is entirely correct because it uses the C preprocessor.
-You can use the variables `c-macro-preprocessor' and `c-macro-options'
-to customize how preprocessing is done, or specify header file directories
-and macros to predefine."
- (interactive "r")
- (let ((outbuf (get-buffer-create "*Macroexpansion*"))
- (tempfile "%%macroexpand%%")
- expanded
- process
- last-needed)
- (setq expanded (expand-file-name tempfile))
- (save-excursion
- (set-buffer outbuf)
- (erase-buffer))
- (setq process (apply 'start-process "macros" outbuf c-macro-preprocessor
- c-macro-options))
- (set-process-sentinel process '(lambda (&rest x)))
- (save-restriction
- (widen)
- (save-excursion
- (goto-char beg)
- (beginning-of-line)
- (setq last-needed (point))
- (if (re-search-backward "^[ \t]*#" nil t)
- (progn
- ;; Skip continued lines.
- (while (progn (end-of-line) (= (preceding-char) ?\\))
- (forward-line 1))
- ;; Skip the last line of the macro definition we found.
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;; USAGE =============================================================
+
+;; In C mode C-C C-e is bound to c-macro-expand. The result of the
+;; expansion is put in a separate buffer. A user option allows the
+;; window displaying the buffer to be optimally sized.
+;;
+;; When called with a C-u prefix, c-macro-expand replaces the selected
+;; region with the expansion. Both the preprocessor name and the
+;; initial flag can be set by the user. If c-macro-prompt-flag is set
+;; to a non-nil value the user is offered to change the options to the
+;; preprocessor each time c-macro-expand is invoked. Preprocessor
+;; arguments default to the last ones entered. If c-macro-prompt-flag
+;; is nil, one must use M-x set-variable to set a different value for
+;; c-macro-cppflags.
+
+;; A c-macro-expansion function is provided for non-interactive use.
+
+;; INSTALLATION ======================================================
+
+;; Put the following in your ~/.emacs file.
+
+;; If you want the *Macroexpansion* window to be not higher than
+;; necessary:
+;;(setq c-macro-shrink-window-flag t)
+;;
+;; If you use a preprocessor other than /lib/cpp (be careful to set a
+;; -C option or equivalent in order to make the preprocessor not to
+;; strip the comments):
+;;(setq c-macro-preprocessor "gpp -C")
+;;
+;; If you often use a particular set of flags:
+;;(setq c-macro-cppflags "-I /usr/include/local -DDEBUG"
+;;
+;; If you want the "Preprocessor arguments: " prompt:
+;;(setq c-macro-prompt-flag t)
+
+;; BUG REPORTS =======================================================
+
+;; Please report bugs, suggestions, complaints and so on to
+;; pot@cnuce.cnr.it (Francesco Potorti`).
+
+;; IMPROVEMENTS OVER emacs 18.xx cmacexp.el ==========================
+
+;; - A lot of user and programmer visible changes. See above.
+;; - #line directives are inserted, so __LINE__ and __FILE__ are
+;; correctly expanded. Works even with START inside a string, a
+;; comment or a region #ifdef'd away by cpp. cpp is invoked with -C,
+;; making comments visible in the expansion.
+;; - All work is done in core memory, no need for temporary files.
+
+;; ACKNOWLEDGEMENTS ==================================================
+
+;; A lot of thanks to Don Maszle who did a great work of testing, bug
+;; reporting and suggestion of new features. This work has been
+;; partially inspired by Don Maszle and Jonathan Segal's.
+
+;; BUGS ==============================================================
+
+;; If the start point of the region is inside a macro definition the
+;; macro expansion is often inaccurate.
+
+
+(require 'cc-mode)
+
+(provide 'cmacexp)
+
+(defgroup c-macro nil
+ "Expand C macros in a region."
+ :group 'c)
+
+
+(defcustom c-macro-shrink-window-flag nil
+ "*Non-nil means shrink the *Macroexpansion* window to fit its contents."
+ :type 'boolean
+ :group 'c-macro)
+
+(defcustom c-macro-prompt-flag nil
+ "*Non-nil makes `c-macro-expand' prompt for preprocessor arguments."
+ :type 'boolean
+ :group 'c-macro)
+
+(defcustom c-macro-preprocessor
+ ;; Cannot rely on standard directory on MS-DOS to find CPP.
+ (cond ((eq system-type 'ms-dos) "cpp -C")
+ ;; Solaris has it in an unusual place.
+ ((and (string-match "^[^-]*-[^-]*-\\(solaris\\|sunos5\\)"
+ system-configuration)
+ (file-exists-p "/opt/SUNWspro/SC3.0.1/bin/acomp"))
+ "/opt/SUNWspro/SC3.0.1/bin/acomp -C -E")
+ (t "/lib/cpp -C"))
+ "The preprocessor used by the cmacexp package.
+
+If you change this, be sure to preserve the `-C' (don't strip comments)
+option, or to set an equivalent one."
+ :type 'string
+ :group 'c-macro)
+
+(defcustom c-macro-cppflags ""
+ "*Preprocessor flags used by `c-macro-expand'."
+ :type 'string
+ :group 'c-macro)
+
+(defconst c-macro-buffer-name "*Macroexpansion*")
+
+;;;###autoload
+(defun c-macro-expand (start end subst)
+ "Expand C macros in the region, using the C preprocessor.
+Normally display output in temp buffer, but
+prefix arg means replace the region with it.
+
+`c-macro-preprocessor' specifies the preprocessor to use.
+Prompt for arguments to the preprocessor \(e.g. `-DDEBUG -I ./include')
+if the user option `c-macro-prompt-flag' is non-nil.
+
+Noninteractive args are START, END, SUBST.
+For use inside Lisp programs, see also `c-macro-expansion'."
+
+ (interactive "r\nP")
+ (let ((inbuf (current-buffer))
+ (displaybuf (if subst
+ (get-buffer c-macro-buffer-name)
+ (get-buffer-create c-macro-buffer-name)))
+ (expansion ""))
+ ;; Build the command string.
+ (if c-macro-prompt-flag
+ (setq c-macro-cppflags
+ (read-string "Preprocessor arguments: "
+ c-macro-cppflags)))
+ ;; Decide where to display output.
+ (if (and subst
+ (and buffer-read-only (not inhibit-read-only))
+ (not (eq inbuf displaybuf)))
+ (progn
+ (message
+ "Buffer is read only: displaying expansion in alternate window")
+ (sit-for 2)
+ (setq subst nil)
+ (or displaybuf
+ (setq displaybuf (get-buffer-create c-macro-buffer-name)))))
+ ;; Expand the macro and output it.
+ (setq expansion (c-macro-expansion start end
+ (concat c-macro-preprocessor " "
+ c-macro-cppflags) t))
+ (if subst
+ (let ((exchange (= (point) start)))
+ (delete-region start end)
+ (insert expansion)
+ (if exchange
+ (exchange-point-and-mark)))
+ (set-buffer displaybuf)
+ (setq buffer-read-only nil)
+ (buffer-disable-undo displaybuf)
+ (erase-buffer)
+ (insert expansion)
+ (set-buffer-modified-p nil)
+ (if (string= "" expansion)
+ (message "Null expansion")
+ (c-macro-display-buffer))
+ (setq buffer-read-only t)
+ (setq buffer-auto-save-file-name nil)
+ (bury-buffer displaybuf))))
+
+
+;; Display the current buffer in a window which is either just large
+;; enough to contain the entire buffer, or half the size of the
+;; screen, whichever is smaller. Do not select the new
+;; window.
+;;
+;; Several factors influence window resizing so that the window is
+;; sized optimally if it is created anew, and so that it is messed
+;; with minimally if it has been created by the user. If the window
+;; chosen for display exists already but contains something else, the
+;; window is not re-sized. If the window already contains the current
+;; buffer, it is never shrunk, but possibly expanded. Finally, if the
+;; variable c-macro-shrink-window-flag is nil the window size is *never*
+;; changed.
+(defun c-macro-display-buffer ()
+ (goto-char (point-min))
+ (c-mode)
+ (let ((oldwinheight (window-height))
+ (alreadythere ;the window was already there
+ (get-buffer-window (current-buffer)))
+ (popped nil)) ;the window popped changing the layout
+ (or alreadythere
+ (progn
+ (display-buffer (current-buffer) t)
+ (setq popped (/= oldwinheight (window-height)))))
+ (if (and c-macro-shrink-window-flag ;user wants fancy shrinking :\)
+ (or alreadythere popped))
+ ;; Enlarge up to half screen, or shrink properly.
+ (let ((oldwin (selected-window))
+ (minheight 0)
+ (maxheight 0))
+ (save-excursion
+ (select-window (get-buffer-window (current-buffer)))
+ (setq minheight (if alreadythere
+ (window-height)
+ window-min-height))
+ (setq maxheight (/ (frame-height) 2))
+ (enlarge-window (- (min maxheight
+ (max minheight
+ (+ 2 (vertical-motion (point-max)))))
+ (window-height)))
+ (goto-char (point-min))
+ (select-window oldwin))))))
+
+
+(defun c-macro-expansion (start end cppcommand &optional display)
+ "Run a preprocessor on region and return the output as a string.
+Expand the region between START and END in the current buffer using
+the shell command CPPCOMMAND (e.g. \"/lib/cpp -C -DDEBUG\").
+Be sure to use a -C (don't strip comments) or equivalent option.
+Optional arg DISPLAY non-nil means show messages in the echo area."
+
+;; Copy the current buffer's contents to a temporary hidden buffer.
+;; Delete from END to end of buffer. Insert a preprocessor #line
+;; directive at START and after each #endif following START that are
+;; not inside a comment or a string. Put all the strings thus
+;; inserted (without the "line" substring) in a list named linelist.
+;; If START is inside a comment, prepend "*/" and append "/*" to the
+;; #line directive. If inside a string, prepend and append "\"".
+;; Preprocess the buffer contents, then look for all the lines stored
+;; in linelist starting from end of buffer. The last line so found is
+;; where START was, so return the substring from point to end of
+;; buffer.
+ (let ((inbuf (current-buffer))
+ (outbuf (get-buffer-create " *C Macro Expansion*"))
+ (filename (if (and buffer-file-name
+ (string-match (regexp-quote default-directory)
+ buffer-file-name))
+ (substring buffer-file-name (match-end 0))
+ (buffer-name)))
+ (mymsg (format "Invoking %s%s%s on region..."
+ c-macro-preprocessor
+ (if (string= "" c-macro-cppflags) "" " ")
+ c-macro-cppflags))
+ (uniquestring "??? !!! ??? start of c-macro expansion ??? !!! ???")
+ (startlinenum 0)
+ (linenum 0)
+ (startstat ())
+ (startmarker "")
+ (exit-status 0)
+ (tempname (make-temp-name
+ (expand-file-name "cmacexp"
+ temporary-file-directory))))
+ (unwind-protect
+ (save-excursion
+ (save-restriction
+ (widen)
+ (let ((in-syntax-table (syntax-table)))
+ (set-buffer outbuf)
+ (setq buffer-read-only nil)
+ (erase-buffer)
+ (set-syntax-table in-syntax-table))
+ (insert-buffer-substring inbuf 1 end))
+
+ ;; We have copied inbuf to outbuf. Point is at end of
+ ;; outbuf. Inset a newline at the end, so cpp can correctly
+ ;; parse a token ending at END.
+ (insert "\n")
+
+ ;; Save sexp status and line number at START.
+ (setq startstat (parse-partial-sexp 1 start))
+ (setq startlinenum (+ (count-lines 1 (point))
+ (if (bolp) 1 0)))
+
+ ;; Now we insert the #line directives after all #endif or
+ ;; #else following START going backward, so the lines we
+ ;; insert don't change the line numbers.
+ ;(switch-to-buffer outbuf) (debug) ;debugging instructions
+ (goto-char (point-max))
+ (while (re-search-backward "\n#\\(endif\\|else\\)\\>" start 'move)
+ (if (equal (nthcdr 3 (parse-partial-sexp start (point)
+ nil nil startstat))
+ '(nil nil nil 0 nil)) ;neither in string nor in
+ ;comment nor after quote
+ (progn
+ (goto-char (match-end 0))
+ (setq linenum (+ startlinenum
+ (count-lines start (point))))
+ (insert (format "\n#line %d \"%s\"\n" linenum filename))
+ (goto-char (match-beginning 0)))))
+
+ ;; Now we are at START. Insert the first #line directive.
+ ;; This must work even inside a string or comment, or after a
+ ;; quote.
+ (let* ((startinstring (nth 3 startstat))
+ (startincomment (nth 4 startstat))
+ (startafterquote (nth 5 startstat))
+ (startinbcomment (nth 7 startstat)))
+ (insert (if startafterquote " " "")
+ (cond (startinstring
+ (char-to-string startinstring))
+ (startincomment "*/")
+ (""))
+ (setq startmarker
+ (concat "\n" uniquestring
+ (cond (startinstring
+ (char-to-string startinstring))
+ (startincomment "/*")
+ (startinbcomment "//"))
+ (if startafterquote "\\")))
+ (format "\n#line %d \"%s\"\n" startlinenum filename)))
+
+ ;; Call the preprocessor.
+ (if display (message mymsg))
+ (setq exit-status
+ (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.
+ (insert "\nPreprocessor produced no output\n")
+ ;; Find and delete the mark of the start of the expansion.
+ ;; Look for `# nn "file.c"' lines and delete them.
+ (goto-char (point-min))
+ (search-forward startmarker)
+ (delete-region 1 (point)))
+ (while (re-search-forward (concat "^# [0-9]+ \""
+ (regexp-quote filename)
+ "\"") nil t)
+ (beginning-of-line)
+ (let ((beg (point)))
(forward-line 1)
- (setq last-needed (point)))))
- (write-region (point-min) last-needed expanded nil 'nomsg)
- ;; Output comment ender in case last #-directive is inside a comment.
- ;; Also, terminate any string that we are in.
- (write-region "*//*\"*/\n" nil expanded t 'nomsg)
- (write-region beg end (concat expanded "x") nil 'nomsg)
- (process-send-string process (concat "#include \"" tempfile "\"\n"))
- (process-send-string process "\n")
- (process-send-string process (concat "#include \"" tempfile "x\"\n"))
- (process-send-eof process)
- ;; HPUX seems to want two eofs.
- (process-send-eof process))
- (while (eq (process-status process) 'run)
- (accept-process-output))
- (delete-file expanded)
- (delete-file (concat expanded "x"))
- (display-buffer outbuf)
- (save-excursion
- (set-buffer outbuf)
- (goto-char (point-max))
- (forward-line -1)
- (delete-region (point) (point-max))
- (re-search-backward "\n# 1 ")
- (forward-line 2)
- (while (eolp) (delete-char 1))
- (delete-region (point-min) (point)))
- (display-buffer outbuf)))
+ (delete-region beg (point))))
+
+ ;; If CPP got errors, show them at the beginning.
+ ;; 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))
+ ;; 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
+ ;; inserted at the end of the buffer.
+ (buffer-substring 1 (max 1 (- (point-max) 1))))
+
+ ;; Cleanup.
+ (kill-buffer outbuf))))
;;; cmacexp.el ends here