;;; hideif.el --- hides selected code within ifdef -*- lexical-binding:t -*-
;; Copyright (C) 1988, 1994, 2001-2020 Free Software Foundation, Inc.
;; Author: Brian Marick
;; Daniel LaLiberte <liberte@holonexus.org>
;; Maintainer: Luke Lee <luke.yx.lee@gmail.com>
;; Keywords: c, outlines
;; 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 3 of the License, 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. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;; To initialize, toggle the hide-ifdef minor mode with
;;
;; M-x hide-ifdef-mode
;;
;; This will set up key bindings and call hide-ifdef-mode-hook if it
;; has a value. To explicitly hide ifdefs using a buffer-local
;; define list (default empty), type
;;
;; M-x hide-ifdefs or C-c @ h
;;
;; Hide-ifdef suppresses the display of code that the preprocessor wouldn't
;; pass through. Support complete C/C++ expression and precedence.
;; It will automatically scan for new #define symbols and macros on the way
;; parsing.
;;
;; The hidden code is marked by ellipses (...). Be
;; cautious when editing near ellipses, since the hidden text is
;; still in the buffer, and you can move the point into it and modify
;; text unawares.
;; You can make your buffer read-only while hide-ifdef-hiding by setting
;; hide-ifdef-read-only to a non-nil value. You can toggle this
;; variable with hide-ifdef-toggle-read-only (C-c @ C-q).
;;
;; You can undo the effect of hide-ifdefs by typing
;;
;; M-x show-ifdefs or C-c @ s
;;
;; Use M-x hide-ifdef-define (C-c @ d) to define a symbol.
;; Use M-x hide-ifdef-undef (C-c @ u) to undefine a symbol.
;;
;; If you define or undefine a symbol while hide-ifdef-mode is in effect,
;; the display will be updated. Only the define list for the current
;; buffer will be affected. You can save changes to the local define
;; list with hide-ifdef-set-define-alist. This adds entries
;; to hide-ifdef-define-alist.
;;
;; If you have defined a hide-ifdef-mode-hook, you can set
;; up a list of symbols that may be used by hide-ifdefs as in the
;; following example:
;;
;; (add-hook 'hide-ifdef-mode-hook
;; (lambda ()
;; (unless hide-ifdef-define-alist
;; (setq hide-ifdef-define-alist
;; '((list1 ONE TWO)
;; (list2 TWO THREE))))
;; (hide-ifdef-use-define-alist 'list2))) ; use list2 by default
;;
;; You can call hide-ifdef-use-define-alist (C-c @ U) at any time to specify
;; another list to use.
;;
;; To cause ifdefs to be hidden as soon as hide-ifdef-mode is called,
;; set hide-ifdef-initially to non-nil.
;;
;; If you set hide-ifdef-lines to t, hide-ifdefs hides all the #ifdef lines.
;; In the absence of highlighting, that might be a bad idea. If you set
;; hide-ifdef-lines to nil (the default), the surrounding preprocessor
;; lines will be displayed. That can be confusing in its own
;; right. Other variations on display are possible, but not much
;; better.
;;
;; You can explicitly hide or show individual ifdef blocks irrespective
;; of the define list by using hide-ifdef-block and show-ifdef-block.
;;
;; You can move the point between ifdefs with forward-ifdef, backward-ifdef,
;; up-ifdef, down-ifdef, next-ifdef, and previous-ifdef.
;;
;; If you have minor-mode-alist in your mode line (the default) two labels
;; may appear. "Ifdef" will appear when hide-ifdef-mode is active. "Hiding"
;; will appear when text may be hidden ("hide-ifdef-hiding" is non-nil).
;;
;; Written by Brian Marick, at Gould, Computer Systems Division, Urbana IL.
;; Extensively modified by Daniel LaLiberte (while at Gould).
;;
;; Extensively modified by Luke Lee in 2013 to support complete C expression
;; evaluation and argumented macro expansion.
;;; Code:
(require 'cc-mode)
(require 'cl-lib)
(defgroup hide-ifdef nil
"Hide selected code within `ifdef'."
:group 'c)
(defcustom hide-ifdef-initially nil
"Non-nil means call `hide-ifdefs' when Hide-Ifdef mode is first activated."
:type 'boolean)
(defcustom hide-ifdef-read-only nil
"Set to non-nil if you want buffer to be read-only while hiding text."
:type 'boolean)
(defcustom hide-ifdef-lines nil
"Non-nil means hide the #ifX, #else, and #endif lines."
:type 'boolean)
(defcustom hide-ifdef-shadow nil
"Non-nil means shadow text instead of hiding it."
:type 'boolean
:version "23.1")
(defface hide-ifdef-shadow '((t (:inherit shadow)))
"Face for shadowing ifdef blocks."
:version "23.1")
(defcustom hide-ifdef-exclude-define-regexp nil
"Ignore #define names if those names match this exclusion pattern."
:type '(choice (const nil) string)
:version "25.1")
(defcustom hide-ifdef-expand-reinclusion-protection t
"Non-nil means don't hide an entire header file enclosed by #ifndef...#endif.
Most C/C++ headers are usually wrapped with ifdefs to prevent re-inclusion:
----- beginning of file -----
#ifndef _XXX_HEADER_FILE_INCLUDED_
#define _XXX_HEADER_FILE_INCLUDED_
xxx
xxx
xxx...
#endif
----- end of file -----
The first time we visit such a file, _XXX_HEADER_FILE_INCLUDED_ is
undefined, and so nothing is hidden. The next time we visit it, everything will
be hidden.
This behavior is generally undesirable. If this option is non-nil, the outermost
#if is always visible."
:type 'boolean
:version "25.1")
(defcustom hide-ifdef-header-regexp
"\\.h\\(h\\|xx\\|pp\\|\\+\\+\\)?\\'"
"C/C++ header file name patterns to determine if current buffer is a header.
Effective only if `hide-ifdef-expand-reinclusion-protection' is t."
:type 'regexp
:version "25.1")
(defvar hide-ifdef-mode-submap
;; Set up the submap that goes after the prefix key.
(let ((map (make-sparse-keymap)))
(define-key map "d" 'hide-ifdef-define)
(define-key map "u" 'hide-ifdef-undef)
(define-key map "D" 'hide-ifdef-set-define-alist)
(define-key map "U" 'hide-ifdef-use-define-alist)
(define-key map "h" 'hide-ifdefs)
(define-key map "s" 'show-ifdefs)
(define-key map "\C-d" 'hide-ifdef-block)
(define-key map "\C-s" 'show-ifdef-block)
(define-key map "e" 'hif-evaluate-macro)
(define-key map "C" 'hif-clear-all-ifdef-defined)
(define-key map "\C-q" 'hide-ifdef-toggle-read-only)
(define-key map "\C-w" 'hide-ifdef-toggle-shadowing)
(substitute-key-definition
'read-only-mode 'hide-ifdef-toggle-outside-read-only map)
;; `toggle-read-only' is obsoleted by `read-only-mode'.
(substitute-key-definition
'toggle-read-only 'hide-ifdef-toggle-outside-read-only map)
map)
"Keymap used by `hide-ifdef-mode' under `hide-ifdef-mode-prefix-key'.")
(defcustom hide-ifdef-mode-prefix-key "\C-c@"
"Prefix key for all Hide-Ifdef mode commands."
:type 'key-sequence
:version "27.1")
(defvar hide-ifdef-mode-map
;; Set up the mode's main map, which leads via the prefix key to the submap.
(let ((map (make-sparse-keymap)))
(define-key map hide-ifdef-mode-prefix-key hide-ifdef-mode-submap)
map)
"Keymap used with `hide-ifdef-mode'.")
(easy-menu-define hide-ifdef-mode-menu hide-ifdef-mode-map
"Menu for `hide-ifdef-mode'."
'("Hide-Ifdef"
["Hide some ifdefs" hide-ifdefs
:help "Hide the contents of some #ifdefs"]
["Show all ifdefs" show-ifdefs
:help "Cancel the effects of `hide-ifdef': show the contents of all #ifdefs"]
["Hide ifdef block" hide-ifdef-block
:help "Hide the ifdef block (true or false part) enclosing or before the cursor"]
["Show ifdef block" show-ifdef-block
:help "Show the ifdef block (true or false part) enclosing or before the cursor"]
["Define a variable..." hide-ifdef-define
:help "Define a VAR so that #ifdef VAR would be included"]
["Undefine a variable..." hide-ifdef-undef
:help "Undefine a VAR so that #ifdef VAR would not be included"]
["Define an alist..." hide-ifdef-set-define-alist
:help "Set the association for NAME to `hide-ifdef-env'"]
["Use an alist..." hide-ifdef-use-define-alist
:help "Set `hide-ifdef-env' to the define list specified by NAME"]
["Toggle read only" hide-ifdef-toggle-read-only
:style toggle :selected hide-ifdef-read-only
:help "Buffer should be read-only while hiding text"]
["Toggle shadowing" hide-ifdef-toggle-shadowing
:style toggle :selected hide-ifdef-shadow
:help "Text should be shadowed instead of hidden"]))
(defvar hide-ifdef-hiding nil
"Non-nil when text may be hidden.")
(or (assq 'hide-ifdef-hiding minor-mode-alist)
(setq minor-mode-alist
(cons '(hide-ifdef-hiding " Hiding")
minor-mode-alist)))
;; Fix c-mode syntax table so we can recognize whole symbols.
(defvar hide-ifdef-syntax-table
(let ((st (copy-syntax-table c-mode-syntax-table)))
(modify-syntax-entry ?_ "w" st)
(modify-syntax-entry ?& "." st)
(modify-syntax-entry ?\| "." st)
st)
"Syntax table used for tokenizing #if expressions.")
(defvar hide-ifdef-env nil
"An alist of defined symbols and their values.")
(defvar hide-ifdef-env-backup nil
"This variable is a backup of the previously cleared `hide-ifdef-env'.
This backup prevents any accidental clearance of `hide-fidef-env' by
`hif-clear-all-ifdef-defined'.")
(defvar hif-outside-read-only nil
"Internal variable. Saves the value of `buffer-read-only' while hiding.")
;;;###autoload
(define-minor-mode hide-ifdef-mode
"Toggle features to hide/show #ifdef blocks (Hide-Ifdef mode).
Hide-Ifdef mode is a buffer-local minor mode for use with C and
C-like major modes. When enabled, code within #ifdef constructs
that the C preprocessor would eliminate may be hidden from view.
Several variables affect how the hiding is done:
`hide-ifdef-env'
An association list of defined and undefined symbols for the
current project. Initially, the global value of `hide-ifdef-env'
is used. This variable was a buffer-local variable, which limits
hideif to parse only one C/C++ file at a time. We've extended
hideif to support parsing a C/C++ project containing multiple C/C++
source files opened simultaneously in different buffers. Therefore
`hide-ifdef-env' can no longer be buffer local but must be global.
`hide-ifdef-define-alist'
An association list of defined symbol lists.
Use `hide-ifdef-set-define-alist' to save the current `hide-ifdef-env'
and `hide-ifdef-use-define-alist' to set the current `hide-ifdef-env'
from one of the lists in `hide-ifdef-define-alist'.
`hide-ifdef-lines'
Set to non-nil to not show #if, #ifdef, #ifndef, #else, and
#endif lines when hiding.
`hide-ifdef-initially'
Indicates whether `hide-ifdefs' should be called when Hide-Ifdef mode
is activated.
`hide-ifdef-read-only'
Set to non-nil if you want to make buffers read only while hiding.
After `show-ifdefs', read-only status is restored to previous value.
\\{hide-ifdef-mode-map}"
:group 'hide-ifdef :lighter " Ifdef"
(if hide-ifdef-mode
(progn
;; inherit global values
;; `hide-ifdef-env' is now a global variable.
;; We can still simulate the behavior of older hideif versions (i.e.
;; `hide-ifdef-env' being buffer local) by clearing this variable
;; (C-c @ C) everytime before hiding current buffer.
;; (set (make-local-variable 'hide-ifdef-env)
;; (default-value 'hide-ifdef-env))
(set 'hide-ifdef-env (default-value 'hide-ifdef-env))
;; Some C/C++ headers might have other ways to prevent reinclusion and
;; thus would like `hide-ifdef-expand-reinclusion-protection' to be nil.
(set (make-local-variable 'hide-ifdef-expand-reinclusion-protection)
(default-value 'hide-ifdef-expand-reinclusion-protection))
(set (make-local-variable 'hide-ifdef-hiding)
(default-value 'hide-ifdef-hiding))
(set (make-local-variable 'hif-outside-read-only) buffer-read-only)
(set (make-local-variable 'line-move-ignore-invisible) t)
(add-hook 'change-major-mode-hook
(lambda () (hide-ifdef-mode -1)) nil t)
(add-to-invisibility-spec '(hide-ifdef . t))
(if hide-ifdef-initially
(hide-ifdefs)
(show-ifdefs)))
;; else end hide-ifdef-mode
(kill-local-variable 'line-move-ignore-invisible)
(remove-from-invisibility-spec '(hide-ifdef . t))
(when hide-ifdef-hiding
(show-ifdefs))))
(defun hif-clear-all-ifdef-defined ()
"Clears all symbols defined in `hide-ifdef-env'.
It will backup this variable to `hide-ifdef-env-backup' before clearing to
prevent accidental clearance."
(interactive)
(when (y-or-n-p "Clear all #defined symbols? ")
(setq hide-ifdef-env-backup hide-ifdef-env)
(setq hide-ifdef-env nil)))
(defun hif-show-all ()
"Show all of the text in the current buffer."
(interactive)
(hif-show-ifdef-region (point-min) (point-max)))
;; By putting this on after-revert-hook, we arrange that it only
;; does anything when revert-buffer avoids turning off the mode.
;; (That can happen in VC.)
(defun hif-after-revert-function ()
(and hide-ifdef-mode hide-ifdef-hiding
(hide-ifdefs t)))
(add-hook 'after-revert-hook 'hif-after-revert-function)
(defun hif-end-of-line ()
(end-of-line)
(while (= (logand 1 (skip-chars-backward "\\\\")) 1)
(end-of-line 2)))
(defun hif-merge-ifdef-region (start end)
"This function merges nearby ifdef regions to form a bigger overlay.
The region is defined by START and END. This will decrease the number of
overlays created."
;; Generally there is no need to call itself recursively since there should
;; originally exists no un-merged regions; however, if a part of the file is
;; hidden with `hide-ifdef-lines' equals to nil while another part with 't,
;; this case happens.
;; TODO: Should we merge? or just create a container overlay? -- this can
;; prevent `hideif-show-ifdef' expanding too many hidden contents since there
;; is only a big overlay exists there without any smaller overlays.
(save-restriction
(widen) ; Otherwise `point-min' and `point-max' will be restricted and thus
; fail to find neighbor overlays
(let ((begovrs (overlays-in
(max (- start 2) (point-min))
(max (- start 1) (point-min))))
(endovrs (overlays-in
(min (+ end 1) (point-max))
(min (+ end 2) (point-max))))
(ob nil)
(oe nil)
b e)
;; Merge overlays before START
(dolist (o begovrs)
(when (overlay-get o 'hide-ifdef)
(setq b (min start (overlay-start o))
e (max end (overlay-end o)))
(move-overlay o b e)
(hif-merge-ifdef-region b e)
(setq ob o)))
;; Merge overlays after END
(dolist (o endovrs)
(when (overlay-get o 'hide-ifdef)
(setq b (min start (overlay-start o))
e (max end (overlay-end o)))
(move-overlay o b e)
(hif-merge-ifdef-region b e)
(setf oe o)))
;; If both START and END merging happens, merge into bigger one
(when (and ob oe)
(let ((b (min (overlay-start ob) (overlay-start oe)))
(e (max (overlay-end ob) (overlay-end oe))))
(delete-overlay oe)
(move-overlay ob b e)
(hif-merge-ifdef-region b e)))
(or ob oe))))
(defun hide-ifdef-region-internal (start end)
(unless (hif-merge-ifdef-region start end)
(let ((o (make-overlay start end)))
(overlay-put o 'hide-ifdef t)
(if hide-ifdef-shadow
(overlay-put o 'face 'hide-ifdef-shadow)
(overlay-put o 'invisible 'hide-ifdef)))))
(defun hide-ifdef-region (start end)
"START is the start of a #if, #elif, or #else form. END is the ending part.
Everything including these lines is made invisible."
(save-excursion
(goto-char start) (hif-end-of-line) (setq start (point))
(goto-char end) (hif-end-of-line) (setq end (point))
(hide-ifdef-region-internal start end)))
(defun hif-show-ifdef-region (start end)
"Everything between START and END is made visible."
(let ((onum (length (overlays-in start end))))
(remove-overlays start end 'hide-ifdef t)
(/= onum (length (overlays-in start end)))))
;;===%%SF%% evaluation (Start) ===
;; It is not useful to set this to anything but `eval'.
;; In fact, the variable might as well be eliminated.
(defvar hide-ifdef-evaluator 'eval
"The function to use to evaluate a form.
The evaluator is given a canonical form and returns t if text under
that form should be displayed.")
(defvar hif-undefined-symbol nil
"...is by default considered to be false.")
(defun hif-set-var (var value)
"Prepend (VAR VALUE) pair to `hide-ifdef-env'."
(setq hide-ifdef-env (cons (cons var value) hide-ifdef-env)))
(declare-function semantic-c-hideif-lookup "semantic/bovine/c" (var))
(declare-function semantic-c-hideif-defined "semantic/bovine/c" (var))
(defun hif-lookup (var)
(or (when (bound-and-true-p semantic-c-takeover-hideif)
(semantic-c-hideif-lookup var))
(let ((val (assoc var hide-ifdef-env)))
(if val
(cdr val)
hif-undefined-symbol))))
(defun hif-defined (var)
(cond
((bound-and-true-p semantic-c-takeover-hideif)
(semantic-c-hideif-defined var))
((assoc var hide-ifdef-env) 1)
(t 0)))
;;===%%SF%% evaluation (End) ===
;;===%%SF%% parsing (Start) ===
;;; The code that understands what ifs and ifdef in files look like.
(defconst hif-cpp-prefix "\\(^\\|\r\\)[ \t]*#[ \t]*")
(defconst hif-ifxdef-regexp (concat hif-cpp-prefix "if\\(n\\)?def"))
(defconst hif-ifndef-regexp (concat hif-cpp-prefix "ifndef"))
(defconst hif-ifx-regexp (concat hif-cpp-prefix "if\\(n?def\\)?[ \t]+"))
(defconst hif-elif-regexp (concat hif-cpp-prefix "elif"))
(defconst hif-else-regexp (concat hif-cpp-prefix "else"))
(defconst hif-endif-regexp (concat hif-cpp-prefix "endif"))
(defconst hif-ifx-else-endif-regexp
(concat hif-ifx-regexp "\\|" hif-elif-regexp "\\|" hif-else-regexp "\\|"
hif-endif-regexp))
(defconst hif-macro-expr-prefix-regexp
(concat hif-cpp-prefix "\\(if\\(n?def\\)?\\|elif\\|define\\)[ \t]+"))
(defconst hif-white-regexp "[ \t]*")
(defconst hif-define-regexp (concat hif-cpp-prefix "\\(define\\|undef\\)"))
(defconst hif-id-regexp (concat "[[:alpha:]_][[:alnum:]_]*"))
(defconst hif-macroref-regexp
(concat hif-white-regexp "\\(" hif-id-regexp "\\)" hif-white-regexp
"\\("
"(" hif-white-regexp
"\\(" hif-id-regexp "\\)?" hif-white-regexp
"\\(" "," hif-white-regexp hif-id-regexp hif-white-regexp "\\)*"
"\\(\\.\\.\\.\\)?" hif-white-regexp
")"
"\\)?" ))
;; Store the current token and the whole token list during parsing.
;; Bound dynamically.
(defvar hif-token)
(defvar hif-token-list)
(defconst hif-token-alist
'(("||" . hif-or)
("&&" . hif-and)
("|" . hif-logior)
("^" . hif-logxor)
("&" . hif-logand)
("<<" . hif-shiftleft)
(">>" . hif-shiftright)
("==" . hif-equal)
;; Note: we include tokens like `=' which aren't supported by CPP's
;; expression syntax, because they are still relevant for the tokenizer,
;; especially in conjunction with ##.
("=" . hif-assign)
("!=" . hif-notequal)
("##" . hif-token-concat)
("!" . hif-not)
("~" . hif-lognot)
("(" . hif-lparen)
(")" . hif-rparen)
(">" . hif-greater)
("<" . hif-less)
(">=" . hif-greater-equal)
("<=" . hif-less-equal)
("+" . hif-plus)
("-" . hif-minus)
("*" . hif-multiply)
("/" . hif-divide)
("%" . hif-modulo)
("?" . hif-conditional)
(":" . hif-colon)
("," . hif-comma)
("#" . hif-stringify)
("..." . hif-etc)))
(defconst hif-valid-token-list (mapcar 'cdr hif-token-alist))
(defconst hif-token-regexp
(concat (regexp-opt (mapcar 'car hif-token-alist))
"\\|0x[[:xdigit:]]+\\.?[[:xdigit:]]*"
"\\|[0-9]+\\.?[0-9]*" ;; decimal/octal
"\\|\\w+"))
(defconst hif-string-literal-regexp "\\(\"\\(?:[^\"\\]\\|\\\\.\\)*\"\\)")
(defun hif-string-to-number (string &optional base)
"Like `string-to-number', but it understands non-decimal floats."
(if (or (not base) (= base 10))
(string-to-number string base)
(let* ((parts (split-string string "\\." t "[ \t]+"))
(frac (cadr parts))
(fraclen (length frac))
(quot (expt (if (zerop fraclen)
base
(* base 1.0)) fraclen)))
(/ (string-to-number (concat (car parts) frac) base) quot))))
;; The dynamic binding variable `hif-simple-token-only' is shared only by
;; `hif-tokenize' and `hif-find-define'. The purpose is to prevent `hif-tokenize'
;; from returning one more value to indicate a simple token is scanned. This help
;; speeding up macro evaluation on those very simple cases like integers or
;; literals.
;; Check the long comments before `hif-find-define' for more details. [lukelee]
(defvar hif-simple-token-only)
(defun hif-tokenize (start end)
"Separate string between START and END into a list of tokens."
(let ((token-list nil))
(setq hif-simple-token-only t)
(with-syntax-table hide-ifdef-syntax-table
(save-excursion
(goto-char start)
(while (progn (forward-comment (point-max)) (< (point) end))
;; (message "expr-start = %d" expr-start) (sit-for 1)
(cond
((looking-at "\\\\\n")
(forward-char 2))
((looking-at hif-string-literal-regexp)
(push (substring-no-properties (match-string 1)) token-list)
(goto-char (match-end 0)))
((looking-at hif-token-regexp)
(let ((token (buffer-substring-no-properties
(point) (match-end 0))))
(goto-char (match-end 0))
;; (message "token: %s" token) (sit-for 1)
(push
(or (cdr (assoc token hif-token-alist))
(if (string-equal token "defined") 'hif-defined)
;; TODO:
;; 1. postfix 'l', 'll', 'ul' and 'ull'
;; 2. floating number formats (like 1.23e4)
;; 3. 098 is interpreted as octal conversion error
(if (string-match "0x\\([[:xdigit:]]+\\.?[[:xdigit:]]*\\)"
token)
(hif-string-to-number (match-string 1 token) 16)) ;; hex
(if (string-match "\\`0[0-9]+\\(\\.[0-9]+\\)?\\'" token)
(hif-string-to-number token 8)) ;; octal
(if (string-match "\\`[1-9][0-9]*\\(\\.[0-9]+\\)?\\'"
token)
(string-to-number token)) ;; decimal
(prog1 (intern token)
(setq hif-simple-token-only nil)))
token-list)))
((looking-at "\r") ; Sometimes MS-Windows user will leave CR in
(forward-char 1)) ; the source code. Let's not get stuck here.
(t (error "Bad #if expression: %s" (buffer-string)))))))
(nreverse token-list)))
;;------------------------------------------------------------------------
;; Translate C preprocessor #if expressions using recursive descent.
;; This parser was limited to the operators &&, ||, !, and "defined".
;; Added ==, !=, +, and -. Gary Oberbrunner, garyo@avs.com, 8/9/94
;;
;; Implement the C language operator precedence table. Add all those
;; missing operators that could be used in macros. Luke Lee 2013-09-04
;; | Operator Type | Operator | Associativity |
;; +----------------------+-----------------------------+---------------+
;; | Primary Expression | () [] . -> expr++ expr-- | left-to-right |
;; | Unary Operators | * & + - ! ~ ++expr --expr | right-to-left |
;; | | (typecast) sizeof | |
;; | Binary Operators | * / % | left-to-right |
;; | | + - | |
;; | | >> << | |
;; | | < > <= >= | |
;; | | == != | |
;; | | & | |
;; | | ^ | |
;; | | | | |
;; | | && | |
;; | | || | |
;; | Ternary Operator | ?: | right-to-left |
;; x| Assignment Operators | = += -= *= /= %= >>= <<= &= | right-to-left |
;; | | ^= = | |
;; | Comma | , | left-to-right |
(defsubst hif-nexttoken ()
"Pop the next token from token-list into the let variable `hif-token'."
(setq hif-token (pop hif-token-list)))
(defsubst hif-if-valid-identifier-p (id)
(not (or (numberp id)
(stringp id))))
(defun hif-define-operator (tokens)
"\"Upgrade\" hif-define XXX to `(hif-define XXX)' so it won't be substituted."
(let ((result nil)
(tok nil))
(while (setq tok (pop tokens))
(push
(if (eq tok 'hif-defined)
(progn
(setq tok (cadr tokens))
(if (eq (car tokens) 'hif-lparen)
(if (and (hif-if-valid-identifier-p tok)
(eq (nth 2 tokens) 'hif-rparen))
(setq tokens (cl-cdddr tokens))
(error "#define followed by non-identifier: %S" tok))
(setq tok (car tokens)
tokens (cdr tokens))
(unless (hif-if-valid-identifier-p tok)
(error "#define followed by non-identifier: %S" tok)))
(list 'hif-defined 'hif-lparen tok 'hif-rparen))
tok)
result))
(nreverse result)))
(define-obsolete-function-alias 'hif-flatten #'flatten-tree "27.1")
(defun hif-expand-token-list (tokens &optional macroname expand_list)
"Perform expansion on TOKENS till everything expanded.
Self-reference (directly or indirectly) tokens are not expanded.
EXPAND_LIST is the list of macro names currently being expanded, used for
detecting self-reference."
(catch 'self-referencing
(let ((expanded nil)
(remains (hif-define-operator
(hif-token-concatenation
(hif-token-stringification tokens))))
tok rep)
(if macroname
(setq expand_list (cons macroname expand_list)))
;; Expanding all tokens till list exhausted
(while (setq tok (pop remains))
(if (memq tok expand_list)
;; For self-referencing tokens, don't expand it
(throw 'self-referencing tokens))
(push
(cond
((or (memq tok hif-valid-token-list)
(numberp tok)
(stringp tok))
tok)
((setq rep (hif-lookup tok))
(if (and (listp rep)
(eq (car rep) 'hif-define-macro)) ; A defined macro
;; Recursively expand it
(if (cadr rep) ; Argument list is not nil
(if (not (eq (car remains) 'hif-lparen))
;; No argument, no invocation
tok
;; Argumented macro, get arguments and invoke it.
;; Dynamically bind hif-token-list and hif-token
;; for hif-macro-supply-arguments
(let* ((hif-token-list (cdr remains))
(hif-token nil)
(parmlist (mapcar #'hif-expand-token-list
(hif-get-argument-list)))
(result
(hif-expand-token-list
(hif-macro-supply-arguments tok parmlist)
tok expand_list)))
(setq remains (cons hif-token hif-token-list))
result))
;; Argument list is nil, direct expansion
(setq rep (hif-expand-token-list
(nth 2 rep) ; Macro's token list
tok expand_list))
;; Replace all remaining references immediately
(setq remains (cl-substitute tok rep remains))
rep)
;; Lookup tok returns an atom
rep))
;;[2013-10-22 16:06:12 +0800] Must keep the token, removing
;; this token might results in an incomplete expression that
;; cannot be parsed further.
;;((= 1 (hif-defined tok)) ; defined (hif-defined tok)=1,
;; ;;but empty (hif-lookup tok)=nil, thus remove this token
;; (setq remains (delete tok remains))
;; nil)
(t ; Usual IDs
tok))
expanded))
(flatten-tree (nreverse expanded)))))
(defun hif-parse-exp (token-list &optional macroname)
"Parse the TOKEN-LIST.
Return translated list in prefix form. MACRONAME is applied when invoking
macros to prevent self-reference."
(let ((hif-token-list (hif-expand-token-list token-list macroname)))
(hif-nexttoken)
(prog1
(and hif-token
(hif-exprlist))
(if hif-token ; is there still a token?
(error "Error: unexpected token: %s" hif-token)))))
(defun hif-exprlist ()
"Parse an exprlist: expr { `,' expr}."
(let ((result (hif-expr)))
(if (eq hif-token 'hif-comma)
(let ((temp (list result)))
(while
(progn
(hif-nexttoken)
(push (hif-expr) temp)
(eq hif-token 'hif-comma)))
(cons 'hif-comma (nreverse temp)))
result)))
(defun hif-expr ()
"Parse an expression as found in #if.
expr : or-expr | or-expr `?' expr `:' expr."
(let ((result (hif-or-expr))
middle)
(while (eq hif-token 'hif-conditional)
(hif-nexttoken)
(setq middle (hif-expr))
(if (eq hif-token 'hif-colon)
(progn
(hif-nexttoken)
(setq result (list 'hif-conditional result middle (hif-expr))))
(error "Error: unexpected token: %s" hif-token)))
result))
(defun hif-or-expr ()
"Parse an or-expr : and-expr | or-expr `||' and-expr."
(let ((result (hif-and-expr)))
(while (eq hif-token 'hif-or)
(hif-nexttoken)
(setq result (list 'hif-or result (hif-and-expr))))
result))
(defun hif-and-expr ()
"Parse an and-expr : logior-expr | and-expr `&&' logior-expr."
(let ((result (hif-logior-expr)))
(while (eq hif-token 'hif-and)
(hif-nexttoken)
(setq result (list 'hif-and result (hif-logior-expr))))
result))
(defun hif-logior-expr ()
"Parse a logor-expr : logxor-expr | logor-expr `|' logxor-expr."
(let ((result (hif-logxor-expr)))
(while (eq hif-token 'hif-logior)
(hif-nexttoken)
(setq result (list 'hif-logior result (hif-logxor-expr))))
result))
(defun hif-logxor-expr ()
"Parse a logxor-expr : logand-expr | logxor-expr `^' logand-expr."
(let ((result (hif-logand-expr)))
(while (eq hif-token 'hif-logxor)
(hif-nexttoken)
(setq result (list 'hif-logxor result (hif-logand-expr))))
result))
(defun hif-logand-expr ()
"Parse a logand-expr : eq-expr | logand-expr `&' eq-expr."
(let ((result (hif-eq-expr)))
(while (eq hif-token 'hif-logand)
(hif-nexttoken)
(setq result (list 'hif-logand result (hif-eq-expr))))
result))
(defun hif-eq-expr ()
"Parse an eq-expr : comp | eq-expr `=='|`!=' comp."
(let ((result (hif-comp-expr))
(eq-token nil))
(while (memq hif-token '(hif-equal hif-notequal))
(setq eq-token hif-token)
(hif-nexttoken)
(setq result (list eq-token result (hif-comp-expr))))
result))
(defun hif-comp-expr ()
"Parse a comp-expr : logshift | comp-expr `<'|`>'|`>='|`<=' logshift."
(let ((result (hif-logshift-expr))
(comp-token nil))
(while (memq hif-token '(hif-greater hif-less hif-greater-equal
hif-less-equal))
(setq comp-token hif-token)
(hif-nexttoken)
(setq result (list comp-token result (hif-logshift-expr))))
result))
(defun hif-logshift-expr ()
"Parse a logshift : math | logshift `<<'|`>>' math."
(let ((result (hif-math))
(shift-token nil))
(while (memq hif-token '(hif-shiftleft hif-shiftright))
(setq shift-token hif-token)
(hif-nexttoken)
(setq result (list shift-token result (hif-math))))
result))
(defun hif-math ()
"Parse an expression with + or -.
math : muldiv | math `+'|`-' muldiv."
(let ((result (hif-muldiv-expr))
(math-op nil))
(while (memq hif-token '(hif-plus hif-minus))
(setq math-op hif-token)
(hif-nexttoken)
(setq result (list math-op result (hif-muldiv-expr))))
result))
(defun hif-muldiv-expr ()
"Parse an expression with *,/,%.
muldiv : factor | muldiv `*'|`/'|`%' factor."
(let ((result (hif-factor))
(math-op nil))
(while (memq hif-token '(hif-multiply hif-divide hif-modulo))
(setq math-op hif-token)
(hif-nexttoken)
(setq result (list math-op result (hif-factor))))
result))
(defun hif-factor ()
"Parse a factor.
factor : `!' factor | `~' factor | `(' expr `)' | `defined(' id `)' |
id `(' parmlist `)' | strings | id."
(cond
((eq hif-token 'hif-not)
(hif-nexttoken)
(list 'hif-not (hif-factor)))
((eq hif-token 'hif-lognot)
(hif-nexttoken)
(list 'hif-lognot (hif-factor)))
((eq hif-token 'hif-lparen)
(hif-nexttoken)
(let ((result (hif-exprlist)))
(if (not (eq hif-token 'hif-rparen))
(error "Bad token in parenthesized expression: %s" hif-token)
(hif-nexttoken)
result)))
((eq hif-token 'hif-defined)
(hif-nexttoken)
(let ((paren (when (eq hif-token 'hif-lparen) (hif-nexttoken) t))
(ident hif-token))
(if (memq hif-token '(or and not hif-defined hif-lparen hif-rparen))
(error "Error: unexpected token: %s" hif-token))
(when paren
(hif-nexttoken)
(unless (eq hif-token 'hif-rparen)
(error "Error: expected \")\" after identifier")))
(hif-nexttoken)
`(hif-defined (quote ,ident))))
((numberp hif-token)
(prog1 hif-token (hif-nexttoken)))
((stringp hif-token)
(hif-string-concatenation))
;; Unary plus/minus.
((memq hif-token '(hif-minus hif-plus))
(list (prog1 hif-token (hif-nexttoken)) 0 (hif-factor)))
(t ; identifier
(let ((ident hif-token))
(hif-nexttoken)
(if (eq hif-token 'hif-lparen)
(hif-place-macro-invocation ident)
`(hif-lookup (quote ,ident)))))))
(defun hif-get-argument-list ()
(let ((nest 0)
(parmlist nil) ; A "token" list of parameters, will later be parsed
(parm nil))
(while (or (not (eq (hif-nexttoken) 'hif-rparen))
(/= nest 0))
(if (eq (car (last parm)) 'hif-comma)
(setq parm nil))
(cond
((eq hif-token 'hif-lparen)
(setq nest (1+ nest)))
((eq hif-token 'hif-rparen)
(setq nest (1- nest)))
((and (eq hif-token 'hif-comma)
(= nest 0))
(push (nreverse parm) parmlist)
(setq parm nil)))
(push hif-token parm))
(push (nreverse parm) parmlist) ; Okay even if PARM is nil
(hif-nexttoken) ; Drop the `hif-rparen', get next token
(nreverse parmlist)))
(defun hif-place-macro-invocation (ident)
(let ((parmlist (hif-get-argument-list)))
`(hif-invoke (quote ,ident) (quote ,parmlist))))
(defun hif-string-concatenation ()
"Parse concatenated strings: string | strings string."
(let ((result (substring-no-properties hif-token)))
(while (stringp (hif-nexttoken))
(setq result (concat
(substring result 0 -1) ; remove trailing '"'
(substring hif-token 1)))) ; remove leading '"'
result))
(defun hif-define-macro (_parmlist _token-body)
"A marker for defined macro with arguments.
This macro cannot be evaluated alone without parameters input."
;;TODO: input arguments at run time, use minibuffer to query all arguments
(error
"Argumented macro cannot be evaluated without passing any parameter"))
(defun hif-stringify (a)
"Stringify a number, string or symbol."
(cond
((numberp a)
(number-to-string a))
((atom a)
(symbol-name a))
((stringp a)
(concat "\"" a "\""))
(t
(error "Invalid token to stringify"))))
(defun intern-safe (str)
(if (stringp str)
(intern str)))
(defun hif-token-concat (a b)
"Concatenate two tokens into a longer token.
Currently support only simple token concatenation. Also support weird (but
valid) token concatenation like `>' ## `>' becomes `>>'. Here we take care only
those that can be evaluated during preprocessing time and ignore all those that
can only be evaluated at C(++) runtime (like `++', `--' and `+='...)."
(if (or (memq a hif-valid-token-list)
(memq b hif-valid-token-list))
(let* ((ra (car (rassq a hif-token-alist)))
(rb (car (rassq b hif-token-alist)))
(result (and ra rb
(cdr (assoc (concat ra rb) hif-token-alist)))))
(or result
;;(error "Invalid token to concatenate")
(error "Concatenating \"%s\" and \"%s\" does not give a valid \
preprocessing token"
(or ra (symbol-name a))
(or rb (symbol-name b)))))
(intern-safe (concat (hif-stringify a)
(hif-stringify b)))))
(defun hif-mathify (val)
"Treat VAL as a number: if it's t or nil, use 1 or 0."
(cond ((eq val t) 1)
((null val) 0)
(t val)))
(defun hif-conditional (a b c)
(if (not (zerop (hif-mathify a))) (hif-mathify b) (hif-mathify c)))
(defun hif-and (a b)
(and (not (zerop (hif-mathify a))) (not (zerop (hif-mathify b)))))
(defun hif-or (a b)
(or (not (zerop (hif-mathify a))) (not (zerop (hif-mathify b)))))
(defun hif-not (a)
(zerop (hif-mathify a)))
(defun hif-lognot (a)
(lognot (hif-mathify a)))
(defmacro hif-mathify-binop (fun)
`(lambda (a b)
,(format "Like `%s' but treat t and nil as 1 and 0." fun)
(,fun (hif-mathify a) (hif-mathify b))))
(defun hif-shiftleft (a b)
(setq a (hif-mathify a))
(setq b (hif-mathify b))
(ash a b))
(defun hif-shiftright (a b)
(setq a (hif-mathify a))
(setq b (hif-mathify b))
(ash a (- b)))
(defalias 'hif-multiply (hif-mathify-binop *))
(defalias 'hif-divide (hif-mathify-binop /))
(defalias 'hif-modulo (hif-mathify-binop %))
(defalias 'hif-plus (hif-mathify-binop +))
(defalias 'hif-minus (hif-mathify-binop -))
(defalias 'hif-equal (hif-mathify-binop =))
(defalias 'hif-notequal (hif-mathify-binop /=))
(defalias 'hif-greater (hif-mathify-binop >))
(defalias 'hif-less (hif-mathify-binop <))
(defalias 'hif-greater-equal (hif-mathify-binop >=))
(defalias 'hif-less-equal (hif-mathify-binop <=))
(defalias 'hif-logior (hif-mathify-binop logior))
(defalias 'hif-logxor (hif-mathify-binop logxor))
(defalias 'hif-logand (hif-mathify-binop logand))
(defun hif-comma (&rest expr)
"Evaluate a list of EXPR, return the result of the last item."
(let ((result nil))
(dolist (e expr)
(ignore-errors
(setq result (funcall hide-ifdef-evaluator e))))
result))
(defun hif-token-stringification (l)
"Scan token list for `hif-stringify' ('#') token and stringify the next token."
(let (result)
(while l
(push (if (eq (car l) 'hif-stringify)
(prog1
(if (cadr l)
(hif-stringify (cadr l))
(error "No token to stringify"))
(setq l (cdr l)))
(car l))
result)
(setq l (cdr l)))
(nreverse result)))
(defun hif-token-concatenation (l)
"Scan token list for `hif-token-concat' ('##') token and concatenate two tokens."
(let ((prev nil)
result)
(while l
(while (eq (car l) 'hif-token-concat)
(unless prev
(error "No token before ## to concatenate"))
(unless (cdr l)
(error "No token after ## to concatenate"))
(setq prev (hif-token-concat prev (cadr l)))
(setq l (cddr l)))
(if prev
(setq result (append result (list prev))))
(setq prev (car l)
l (cdr l)))
(if prev
(append result (list prev))
result)))
(defun hif-delimit (lis atom)
(nconc (mapcan (lambda (l) (list l atom))
(butlast lis))
(last lis)))
;; Perform token replacement:
(defun hif-macro-supply-arguments (macro-name actual-parms)
"Expand a macro call, replace ACTUAL-PARMS in the macro body."
(let* ((SA (assoc macro-name hide-ifdef-env))
(macro (and SA
(cdr SA)
(eq (cadr SA) 'hif-define-macro)
(cddr SA)))
(formal-parms (and macro (car macro)))
(macro-body (and macro (cadr macro)))
actual-count
formal-count
formal
etc)
(when (and actual-parms formal-parms macro-body)
;; For each actual parameter, evaluate each one and associate it
;; with an actual parameter, put it into local table and finally
;; evaluate the macro body.
(if (setq etc (eq (car formal-parms) 'hif-etc))
;; Take care of `hif-etc' first. Prefix `hif-comma' back if needed.
(setq formal-parms (cdr formal-parms)))
(setq formal-count (length formal-parms)
actual-count (length actual-parms))
(if (> formal-count actual-count)
(error "Too few parameters for macro %S" macro-name)
(if (< formal-count actual-count)
(or etc
(error "Too many parameters for macro %S" macro-name))))
;; Perform token replacement on the MACRO-BODY with the parameters
(while (setq formal (pop formal-parms))
;; Prevent repetitive substitution, thus cannot use `subst'
;; for example:
;; #define mac(a,b) (a+b)
;; #define testmac mac(b,y)
;; testmac should expand to (b+y): replace of argument a and b
;; occurs simultaneously, not sequentially. If sequentially,
;; according to the argument order, it will become:
;; 1. formal parm #1 'a' replaced by actual parm 'b', thus (a+b)
;; becomes (b+b)
;; 2. formal parm #2 'b' replaced by actual parm 'y', thus (b+b)
;; becomes (y+y).
(setq macro-body
;; Unlike `subst', `substitute' replace only the top level
;; instead of the whole tree; more importantly, it's not
;; destructive.
(cl-substitute (if (and etc (null formal-parms))
(hif-delimit actual-parms 'hif-comma)
(car actual-parms))
formal macro-body))
(setq actual-parms (cdr actual-parms)))
;; Replacement completed, flatten the whole token list
(setq macro-body (flatten-tree macro-body))
;; Stringification and token concatenation happens here
(hif-token-concatenation (hif-token-stringification macro-body)))))
(defun hif-invoke (macro-name actual-parms)
"Invoke a macro by expanding it, reparse macro-body and finally invoke it."
;; Reparse the macro body and evaluate it
(funcall hide-ifdef-evaluator
(hif-parse-exp
(hif-macro-supply-arguments macro-name actual-parms)
macro-name)))
;;;----------- end of parser -----------------------
(defun hif-canonicalize-tokens (regexp) ; For debugging
"Return the expanded result of the scanned tokens."
(save-excursion
(re-search-forward regexp)
(let* ((curr-regexp (match-string 0))
(defined (string-match hif-ifxdef-regexp curr-regexp))
(negate (and defined
(string= (match-string 2 curr-regexp) "n")))
(hif-simple-token-only nil) ;; Dynamic binding var for `hif-tokenize'
(tokens (hif-tokenize (point)
(progn (hif-end-of-line) (point)))))
(if defined
(setq tokens (list 'hif-defined tokens)))
(if negate
(setq tokens (list 'hif-not tokens)))
tokens)))
(defun hif-canonicalize (regexp)
"Return a Lisp expression for its condition by scanning current buffer.
Do this when cursor is at the beginning of `regexp' (i.e. #ifX)."
(let ((case-fold-search nil))
(save-excursion
(re-search-forward regexp)
(let* ((curr-regexp (match-string 0))
(defined (string-match hif-ifxdef-regexp curr-regexp))
(negate (and defined
(string= (match-string 2 curr-regexp) "n")))
(hif-simple-token-only nil) ; Dynamic binding for `hif-tokenize'
(tokens (hif-tokenize (point)
(progn (hif-end-of-line) (point)))))
(if defined
(setq tokens (list 'hif-defined tokens)))
(if negate
(setq tokens (list 'hif-not tokens)))
(hif-parse-exp tokens)))))
(defun hif-find-any-ifX ()
"Move to next #if..., or #ifndef, at point or after."
;; (message "find ifX at %d" (point))
(prog1
(re-search-forward hif-ifx-regexp (point-max) t)
(beginning-of-line)))
(defun hif-find-next-relevant ()
"Move to next #if..., #elif..., #else, or #endif, after the current line."
;; (message "hif-find-next-relevant at %d" (point))
(end-of-line)
;; Avoid infinite recursion by only going to line-beginning if match found
(if (re-search-forward hif-ifx-else-endif-regexp (point-max) t)
(beginning-of-line)))
(defun hif-find-previous-relevant ()
"Move to previous #if..., #else, or #endif, before the current line."
;; (message "hif-find-previous-relevant at %d" (point))
(beginning-of-line)
;; Avoid infinite recursion by only going to line-beginning if match found
(if (re-search-backward hif-ifx-else-endif-regexp (point-min) t)
(beginning-of-line)))
(defun hif-looking-at-ifX ()
(looking-at hif-ifx-regexp)) ; Should eventually see #if
(defun hif-looking-at-endif ()
(looking-at hif-endif-regexp))
(defun hif-looking-at-else ()
(looking-at hif-else-regexp))
(defun hif-looking-at-elif ()
(looking-at hif-elif-regexp))
(defun hif-ifdef-to-endif ()
"If positioned at #ifX, #elif, or #else form, skip to corresponding #endif."
;; (message "hif-ifdef-to-endif at %d" (point)) (sit-for 1)
(hif-find-next-relevant)
(cond ((hif-looking-at-ifX)
(hif-ifdef-to-endif) ; Find endif of nested if
(hif-ifdef-to-endif)) ; Find outer endif or else
((hif-looking-at-elif)
(hif-ifdef-to-endif))
((hif-looking-at-else)
(hif-ifdef-to-endif)) ; Find endif following else
((hif-looking-at-endif)
'done)
(t
(error "Mismatched #ifdef #endif pair"))))
(defun hif-endif-to-ifdef ()
"If positioned at #endif form, skip backward to corresponding #ifX."
;; (message "hif-endif-to-ifdef at %d" (point))
(let ((start (point)))
(hif-find-previous-relevant)
(if (= start (point))
(error "Mismatched #ifdef #endif pair")))
(cond ((hif-looking-at-endif)
(hif-endif-to-ifdef) ; Find beginning of nested if
(hif-endif-to-ifdef)) ; Find beginning of outer if or else
((hif-looking-at-elif)
(hif-endif-to-ifdef))
((hif-looking-at-else)
(hif-endif-to-ifdef))
((hif-looking-at-ifX)
'done)
(t
(error "Mismatched #endif")))) ; never gets here
(defun forward-ifdef (&optional arg)
"Move point to beginning of line of the next ifdef-endif.
With argument, do this that many times."
(interactive "p")
(or arg (setq arg 1))
(if (< arg 0) (backward-ifdef (- arg))
(while (< 0 arg)
(setq arg (- arg))
(let ((start (point)))
(unless (hif-looking-at-ifX)
(hif-find-next-relevant))
(if (hif-looking-at-ifX)
(hif-ifdef-to-endif)
(goto-char start)
(error "No following #ifdef"))))))
(defun backward-ifdef (&optional arg)
"Move point to beginning of the previous ifdef-endif.
With argument, do this that many times."
(interactive "p")
(or arg (setq arg 1))
(if (< arg 0) (forward-ifdef (- arg))
(while (< 0 arg)
(setq arg (1- arg))
(beginning-of-line)
(let ((start (point)))
(unless (hif-looking-at-endif)
(hif-find-previous-relevant))
(if (hif-looking-at-endif)
(hif-endif-to-ifdef)
(goto-char start)
(error "No previous #ifdef"))))))
(defun down-ifdef ()
"Move point to beginning of nested ifdef or else-part."
(interactive)
(let ((start (point)))
(hif-find-next-relevant)
(if (or (hif-looking-at-ifX) (hif-looking-at-else))
()
(goto-char start)
(error "No following #ifdef"))))
(defun up-ifdef ()
"Move point to beginning of enclosing ifdef or else-part."
(interactive)
(beginning-of-line)
(let ((start (point)))
(unless (hif-looking-at-endif)
(hif-find-previous-relevant))
(if (hif-looking-at-endif)
(hif-endif-to-ifdef))
(if (= start (point))
(error "No previous #ifdef"))))
(defun next-ifdef (&optional arg)
"Move to the beginning of the next #ifX, #else, or #endif.
With argument, do this that many times."
(interactive "p")
(or arg (setq arg 1))
(if (< arg 0) (previous-ifdef (- arg))
(while (< 0 arg)
(setq arg (1- arg))
(hif-find-next-relevant)
(when (eolp)
(beginning-of-line)
(error "No following #ifdefs, #elses, or #endifs")))))
(defun previous-ifdef (&optional arg)
"Move to the beginning of the previous #ifX, #else, or #endif.
With argument, do this that many times."
(interactive "p")
(or arg (setq arg 1))
(if (< arg 0) (next-ifdef (- arg))
(while (< 0 arg)
(setq arg (1- arg))
(let ((start (point)))
(hif-find-previous-relevant)
(if (= start (point))
(error "No previous #ifdefs, #elses, or #endifs"))))))
;;===%%SF%% parsing (End) ===
;;===%%SF%% hide-ifdef-hiding (Start) ===
;; A range is a structure with four components:
;; START The start of the range. (beginning of line)
;; ELSE The else marker (beginning of line)
;; END The end of the range. (beginning of line)
;; ELIF A sequence of #elif markers (beginning of line)
(defsubst hif-make-range (start end &optional else elif)
(list start else end elif))
(defsubst hif-range-start (range) (elt range 0))
(defsubst hif-range-else (range) (elt range 1))
(defsubst hif-range-end (range) (elt range 2))
(defsubst hif-range-elif (range) (elt range 3))
;; Find-Range
;; The workhorse, it delimits the #if region. Reasonably simple:
;; Skip until an #else or #endif is found, remembering positions. If
;; an #else was found, skip some more, looking for the true #endif.
(defun hif-find-range ()
"Return a Range structure describing the current #if region.
Point is left unchanged."
;; (message "hif-find-range at %d" (point))
(save-excursion
(beginning-of-line)
(let ((start (point))
(elif nil)
(else nil)
(end nil))
;; Part one. Look for either #elif, #else or #endif.
;; This loop-and-a-half dedicated to E. Dijkstra.
(while (and (not else) (not end))
(while (progn
(hif-find-next-relevant)
(hif-looking-at-ifX)) ; Skip nested ifdef
(hif-ifdef-to-endif))
;; Found either a #else, #elif, or an #endif.
(cond ((hif-looking-at-elif)
(setq elif (nconc elif (list (point)))))
((hif-looking-at-else)
(setq else (point)))
(t
(setq end (point)))))
;; If found #else, look for #endif.
(when else
(while (progn
(hif-find-next-relevant)
(hif-looking-at-ifX)) ; Skip nested ifdef
(hif-ifdef-to-endif))
(if (hif-looking-at-else)
(error "Found two elses in a row? Broken!"))
(setq end (point))) ; (line-end-position)
(hif-make-range start end else elif))))
;; A bit slimy.
(defun hif-hide-line (point)
"Hide the line containing point.
Does nothing if `hide-ifdef-lines' is nil."
(when hide-ifdef-lines
(save-excursion
(goto-char point)
(hide-ifdef-region-internal
(line-beginning-position) (progn (hif-end-of-line) (point))))))
;; Hif-Possibly-Hide
;; There are four cases. The #ifX expression is "taken" if it
;; the hide-ifdef-evaluator returns T. Presumably, this means the code
;; inside the #ifdef would be included when the program was
;; compiled.
;;
;; Case 1: #ifX taken, and there's an #else.
;; The #else part must be hidden. The #if (then) part must be
;; processed for nested #ifX's.
;; Case 2: #ifX taken, and there's no #else.
;; The #if part must be processed for nested #ifX's.
;; Case 3: #ifX not taken, and there's an #elif
;; The #if part must be hidden, and then evaluate
;; the #elif condition like a new #ifX.
;; Case 4: #ifX not taken, and there's just an #else.
;; The #if part must be hidden. The #else part must be processed
;; for nested #ifs.
;; Case 5: #ifX not taken, and there's no #else.
;; The #ifX part must be hidden.
;;
;; Further processing is done by narrowing to the relevant region
;; and just recursively calling hide-ifdef-guts.
;;
;; When hif-possibly-hide returns, point is at the end of the
;; possibly-hidden range.
(defvar hif-recurse-level 0)
(defun hif-recurse-on (start end &optional dont-go-eol)
"Call `hide-ifdef-guts' after narrowing to end of START line and END line."
(save-excursion
(save-restriction
(goto-char start)
(unless dont-go-eol
(end-of-line))
(narrow-to-region (point) end)
(let ((hif-recurse-level (1+ hif-recurse-level)))
(hide-ifdef-guts)))))
(defun hif-possibly-hide (expand-reinclusion)
"Called at #ifX expression, this hides those parts that should be hidden.
It uses the judgment of `hide-ifdef-evaluator'. EXPAND-REINCLUSION is a flag
indicating that we should expand the #ifdef even if it should be hidden.
Refer to `hide-ifdef-expand-reinclusion-protection' for more details."
;; (message "hif-possibly-hide") (sit-for 1)
(let* ((case-fold-search nil)
(test (hif-canonicalize hif-ifx-regexp))
(range (hif-find-range))
(elifs (hif-range-elif range))
(if-part t) ; Everytime we start from if-part
(complete nil))
;; (message "test = %s" test) (sit-for 1)
(hif-hide-line (hif-range-end range))
(while (not complete)
(if (and (not (and expand-reinclusion if-part))
(hif-not (funcall hide-ifdef-evaluator test)))
;; ifX/elif is FALSE
(if elifs
;; Case 3 - Hide the #ifX and eval #elif
(let ((newstart (car elifs)))
(hif-hide-line (hif-range-start range))
(hide-ifdef-region (hif-range-start range)
(1- newstart))
(setcar range newstart)
(goto-char newstart)
(setq elifs (cdr elifs))
(setq test (hif-canonicalize hif-elif-regexp)))
;; Check for #else
(cond ((hif-range-else range)
;; Case 4 - #else block visible
(hif-hide-line (hif-range-else range))
(hide-ifdef-region (hif-range-start range)
(1- (hif-range-else range)))
(hif-recurse-on (hif-range-else range)
(hif-range-end range)))
(t
;; Case 5 - No #else block, hide #ifX
(hide-ifdef-region (point)
(1- (hif-range-end range)))))
(setq complete t))
;; ifX/elif is TRUE
(cond (elifs
;; Luke fix: distinguish from #elif..#elif to #elif..#else
(let ((elif (car elifs)))
;; hide all elifs
(hif-hide-line elif)
(hide-ifdef-region elif (1- (hif-range-end range)))
(hif-recurse-on (hif-range-start range)
elif)))
((hif-range-else range)
;; Case 1 - Hide #elif and #else blocks, recurse #ifX
(hif-hide-line (hif-range-else range))
(hide-ifdef-region (hif-range-else range)
(1- (hif-range-end range)))
(hif-recurse-on (hif-range-start range)
(hif-range-else range)))
(t
;; Case 2 - No #else, just recurse #ifX
(hif-recurse-on (hif-range-start range)
(hif-range-end range))))
(setq complete t))
(setq if-part nil))
;; complete = t
(hif-hide-line (hif-range-start range)) ; Always hide start.
(goto-char (hif-range-end range))
(end-of-line)))
(defun hif-evaluate-region (start end)
(let* ((tokens (ignore-errors ; Prevent C statement things like
; 'do { ... } while (0)'
(hif-tokenize start end)))
(expr (and tokens
(condition-case nil
(hif-parse-exp tokens)
(error
tokens))))
(result (funcall hide-ifdef-evaluator expr)))
result))
(defun hif-evaluate-macro (rstart rend)
"Evaluate the macro expansion result for the active region.
If no region active, find the current #ifdefs and evaluate the result.
Currently it supports only math calculations, strings or argumented macros can
not be expanded."
(interactive
(if (use-region-p)
(list (region-beginning) (region-end))
'(nil nil)))
(let ((case-fold-search nil))
(save-excursion
(unless (use-region-p)
(setq rstart nil rend nil)
(beginning-of-line)
(when (and (re-search-forward hif-macro-expr-prefix-regexp nil t)
(string= "define" (match-string 2)))
(re-search-forward hif-macroref-regexp nil t)))
(let* ((start (or rstart (point)))
(end (or rend (progn (hif-end-of-line) (point))))
(defined nil)
(simple 't)
(tokens (ignore-errors ; Prevent C statement things like
; 'do { ... } while (0)'
(hif-tokenize start end)))
(expr (or (and (<= (length tokens) 1) ; Simple token
(setq defined (assoc (car tokens) hide-ifdef-env))
(setq simple (atom (hif-lookup (car tokens))))
(hif-lookup (car tokens)))
(and tokens
(condition-case nil
(hif-parse-exp tokens)
(error
nil)))))
(result (funcall hide-ifdef-evaluator expr))
(exprstring (replace-regexp-in-string
;; Trim off leading/trailing whites
"^[ \t]*\\([^ \t]+\\)[ \t]*" "\\1"
(replace-regexp-in-string
"\\(//.*\\)" "" ; Trim off end-of-line comments
(buffer-substring-no-properties start end)))))
(cond
((and (<= (length tokens) 1) simple) ; Simple token
(if defined
(message "%S <= `%s'" result exprstring)
(message "`%s' is not defined" exprstring)))
((integerp result)
(if (or (= 0 result) (= 1 result))
(message "%S <= `%s'" result exprstring)
(message "%S (%#x) <= `%s'" result result exprstring)))
((null result) (message "%S <= `%s'" 'false exprstring))
((eq t result) (message "%S <= `%s'" 'true exprstring))
(t (message "%S <= `%s'" result exprstring)))
result))))
(defun hif-parse-macro-arglist (str)
"Parse argument list formatted as `( arg1 [ , argn] [...] )'.
The `...' is also included. Return a list of the arguments, if `...' exists the
first arg will be `hif-etc'."
(let* ((hif-simple-token-only nil) ; Dynamic binding var for `hif-tokenize'
(tokenlist
(cdr (hif-tokenize
(- (point) (length str)) (point)))) ; Remove `hif-lparen'
etc result token)
(while (not (eq (setq token (pop tokenlist)) 'hif-rparen))
(cond
((eq token 'hif-etc)
(setq etc t))
((eq token 'hif-comma)
t)
(t
(push token result))))
(if etc
(cons 'hif-etc (nreverse result))
(nreverse result))))
;; The original version of hideif evaluates the macro early and store the
;; final values for the defined macro into the symbol database (aka
;; `hide-ifdef-env'). The evaluation process is "strings -> tokens -> parsed
;; tree -> [value]". (The square bracket refers to what's stored in our
;; `hide-ifdef-env'.)
;;
;; This forbids the evaluation of an argumented macro since the parameters
;; are applied at run time. In order to support argumented macro I then
;; postponed the evaluation process one stage and store the "parsed tree"
;; into symbol database. The evaluation process was then "strings -> tokens
;; -> [parsed tree] -> value". Hideif therefore run slower since it need to
;; evaluate the parsed tree everytime when trying to expand the symbol. These
;; temporarily code changes are obsolete and not in Emacs source repository.
;;
;; Furthermore, CPP did allow partial expression to be defined in several
;; macros and later got concatenated into a complete expression and then
;; evaluate it. In order to match this behavior I had to postpone one stage
;; further, otherwise those partial expression will be fail on parsing and
;; we'll miss all macros that reference it. The evaluation process thus
;; became "strings -> [tokens] -> parsed tree -> value." This degraded the
;; performance since we need to parse tokens and evaluate them everytime
;; when that symbol is referenced.
;;
;; In real cases I found a lot portion of macros are "simple macros" that
;; expand to literals like integers or other symbols. In order to enhance
;; the performance I use this `hif-simple-token-only' to notify my code and
;; save the final [value] into symbol database. [lukelee]
(defun hif-find-define (&optional min max)
"Parse texts and retrieve all defines within the region MIN and MAX."
(interactive)
(and min (goto-char min))
(and (re-search-forward hif-define-regexp max t)
(or
(let* ((defining (string= "define" (match-string 2)))
(name (and (re-search-forward hif-macroref-regexp max t)
(match-string 1)))
(parmlist (and (match-string 3) ; First arg id found
(hif-parse-macro-arglist (match-string 2)))))
(if defining
;; Ignore name (still need to return 't), or define the name
(or (and hide-ifdef-exclude-define-regexp
(string-match hide-ifdef-exclude-define-regexp
name))
(let* ((start (point))
(end (progn (hif-end-of-line) (point)))
(hif-simple-token-only nil) ; Dynamic binding
(tokens
(and name
;; `hif-simple-token-only' is set/clear
;; only in this block
(condition-case nil
;; Prevent C statements like
;; 'do { ... } while (0)'
(hif-tokenize start end)
(error
;; We can't just return nil here since
;; this will stop hideif from searching
;; for more #defines.
(setq hif-simple-token-only t)
(buffer-substring-no-properties
start end)))))
;; For simple tokens we save only the parsed result;
;; otherwise we save the tokens and parse it after
;; parameter replacement
(expr (and tokens
;; `hif-simple-token-only' is checked only
;; here.
(or (and hif-simple-token-only
(listp tokens)
(= (length tokens) 1)
(hif-parse-exp tokens))
`(hif-define-macro ,parmlist
,tokens))))
(SA (and name
(assoc (intern name) hide-ifdef-env))))
(and name
(if SA
(or (setcdr SA expr) t)
;; Lazy evaluation, eval only if hif-lookup find it.
;; Define it anyway, even if nil it's still in list
;; and therefore considered defined.
(push (cons (intern name) expr) hide-ifdef-env)))))
;; #undef
(and name
(hif-undefine-symbol (intern name))))))
t))
(defun hif-add-new-defines (&optional min max)
"Scan and add all #define macros between MIN and MAX."
(interactive)
(save-excursion
(save-restriction
;; (mark-region min max) ;; for debugging
(while (hif-find-define min max)
(setf min (point)))
(if max (goto-char max)
(goto-char (point-max))))))
(defun hide-ifdef-guts ()
"Does most of the work of `hide-ifdefs'.
It does not do the work that's pointless to redo on a recursive entry."
;; (message "hide-ifdef-guts")
(save-excursion
(let* ((case-fold-search t) ; Ignore case for `hide-ifdef-header-regexp'
(expand-header (and hide-ifdef-expand-reinclusion-protection
(string-match hide-ifdef-header-regexp
(buffer-file-name))
(zerop hif-recurse-level)))
(case-fold-search nil)
min max)
(goto-char (point-min))
(setf min (point))
(cl-loop do
(setf max (hif-find-any-ifX))
(hif-add-new-defines min max)
(if max
(hif-possibly-hide expand-header))
(setf min (point))
while max))))
;;===%%SF%% hide-ifdef-hiding (End) ===
;;===%%SF%% exports (Start) ===
(defun hide-ifdef-toggle-read-only ()
"Toggle `hide-ifdef-read-only'."
(interactive)
(setq hide-ifdef-read-only (not hide-ifdef-read-only))
(message "Hide-Read-Only %s"
(if hide-ifdef-read-only "ON" "OFF"))
(if hide-ifdef-hiding
(setq buffer-read-only (or hide-ifdef-read-only
hif-outside-read-only)))
(force-mode-line-update))
(defun hide-ifdef-toggle-outside-read-only ()
"Replacement for `read-only-mode' within Hide-Ifdef mode."
(interactive)
(setq hif-outside-read-only (not hif-outside-read-only))
(message "Read only %s"
(if hif-outside-read-only "ON" "OFF"))
(setq buffer-read-only
(or (and hide-ifdef-hiding hide-ifdef-read-only)
hif-outside-read-only))
(force-mode-line-update))
(defun hide-ifdef-toggle-shadowing ()
"Toggle shadowing."
(interactive)
(set (make-local-variable 'hide-ifdef-shadow) (not hide-ifdef-shadow))
(message "Shadowing %s" (if hide-ifdef-shadow "ON" "OFF"))
(save-restriction
(widen)
(dolist (overlay (overlays-in (point-min) (point-max)))
(when (overlay-get overlay 'hide-ifdef)
(if hide-ifdef-shadow
(progn
(overlay-put overlay 'invisible nil)
(overlay-put overlay 'face 'hide-ifdef-shadow))
(overlay-put overlay 'face nil)
(overlay-put overlay 'invisible 'hide-ifdef))))))
(defun hide-ifdef-define (var &optional val)
"Define a VAR to VAL (default 1) in `hide-ifdef-env'.
This allows #ifdef VAR to be hidden."
(interactive
(let* ((default (save-excursion
(beginning-of-line)
(cond ((looking-at hif-ifx-else-endif-regexp)
(forward-word-strictly 2)
(current-word 'strict))
(t
nil))))
(var (read-minibuffer "Define what? " default))
(val (read-from-minibuffer (format "Set %s to? (default 1): " var)
nil nil t nil "1")))
(list var val)))
(hif-set-var var (or val 1))
(message "%s set to %s" var (or val 1))
(sleep-for 1)
(if hide-ifdef-hiding (hide-ifdefs)))
(defun hif-undefine-symbol (var)
(setq hide-ifdef-env
(delete (assoc var hide-ifdef-env) hide-ifdef-env)))
(defun hide-ifdef-undef (start end)
"Undefine a VAR so that #ifdef VAR would not be included."
(interactive
(if (use-region-p)
(list (region-beginning) (region-end))
'(nil nil)))
(let* ((symstr
(or (and (number-or-marker-p start)
(number-or-marker-p end)
(buffer-substring-no-properties start end))
(read-string "Undefine what? " (current-word))))
(sym (and symstr
(intern symstr))))
(if (zerop (hif-defined sym))
(message "`%s' not defined, no need to undefine it" symstr)
(hif-undefine-symbol sym)
(if hide-ifdef-hiding (hide-ifdefs))
(message "`%S' undefined" sym))))
(defun hide-ifdefs (&optional nomsg)
"Hide the contents of some #ifdefs.
Assume that defined symbols have been added to `hide-ifdef-env'.
The text hidden is the text that would not be included by the C
preprocessor if it were given the file with those symbols defined.
With prefix command presents it will also hide the #ifdefs themselves.
Turn off hiding by calling `show-ifdefs'."
(interactive)
(let ((hide-ifdef-lines current-prefix-arg))
(or nomsg
(message "Hiding..."))
(setq hif-outside-read-only buffer-read-only)
(unless hide-ifdef-mode (hide-ifdef-mode 1)) ; Turn on hide-ifdef-mode
(if hide-ifdef-hiding
(show-ifdefs)) ; Otherwise, deep confusion.
(setq hide-ifdef-hiding t)
(hide-ifdef-guts)
(setq buffer-read-only (or hide-ifdef-read-only hif-outside-read-only))
(or nomsg
(message "Hiding done"))))
(defun show-ifdefs ()
"Cancel the effects of `hide-ifdef': show the contents of all #ifdefs."
(interactive)
(setq buffer-read-only hif-outside-read-only)
(hif-show-all)
(setq hide-ifdef-hiding nil))
(defun hif-find-ifdef-block ()
"Utility to hide and show ifdef block.
Return as (TOP . BOTTOM) the extent of ifdef block."
(let (max-bottom)
(cons (save-excursion
(beginning-of-line)
(unless (or (hif-looking-at-else) (hif-looking-at-ifX))
(up-ifdef))
(prog1 (point)
(hif-ifdef-to-endif)
(setq max-bottom (1- (point)))))
(save-excursion
(beginning-of-line)
(unless (hif-looking-at-endif)
(hif-find-next-relevant))
(while (hif-looking-at-ifX)
(hif-ifdef-to-endif)
(hif-find-next-relevant))
(min max-bottom (1- (point)))))))
(defun hide-ifdef-block (&optional arg start end)
"Hide the ifdef block (true or false part) enclosing or before the cursor.
With optional prefix argument ARG, also hide the #ifdefs themselves."
(interactive "P\nr")
(let ((hide-ifdef-lines arg))
(if (use-region-p)
(let ((hif-recurse-level (1+ hif-recurse-level)))
(hif-recurse-on start end t)
(setq mark-active nil))
(unless hide-ifdef-mode (hide-ifdef-mode 1))
(let ((top-bottom (hif-find-ifdef-block)))
(hide-ifdef-region (car top-bottom) (cdr top-bottom))
(when hide-ifdef-lines
(hif-hide-line (car top-bottom))
(hif-hide-line (1+ (cdr top-bottom))))
(setq hide-ifdef-hiding t))
(setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only)))))
(defun show-ifdef-block (&optional start end)
"Show the ifdef block (true or false part) enclosing or before the cursor."
(interactive
(if (use-region-p)
(list (region-beginning) (region-end))
'(nil nil)))
(if (and (number-or-marker-p start)
(number-or-marker-p end))
(progn
(dolist (o (overlays-in start end))
(if (overlay-get o 'hide-ifdef)
(delete-overlay o)))
(setq mark-active nil))
(let ((top-bottom (condition-case nil
(hif-find-ifdef-block)
(error
nil)))
(ovrs (overlays-in (max (point-min) (1- (point)))
(min (point-max) (1+ (point)))))
(del nil))
(if top-bottom
(if hide-ifdef-lines
(hif-show-ifdef-region
(save-excursion
(goto-char (car top-bottom)) (line-beginning-position))
(save-excursion
(goto-char (1+ (cdr top-bottom)))
(hif-end-of-line) (point)))
(setf del (hif-show-ifdef-region
(1- (car top-bottom)) (cdr top-bottom)))))
(if (not (and top-bottom
del))
(dolist (o ovrs)
;;(dolist (o (overlays-in (1- (point)) (1+ (point))))
;; (if (overlay-get o 'hide-ifdef) (message "%S" o)))
(if (overlay-get o 'hide-ifdef)
(delete-overlay o)))))))
;;; definition alist support
(defvar hide-ifdef-define-alist nil
"A global assoc list of pre-defined symbol lists.")
(defun hif-compress-define-list (env)
"Compress the define list ENV into a list of defined symbols only."
(let ((new-defs nil))
(dolist (def env new-defs)
(if (hif-lookup (car def)) (push (car def) new-defs)))))
(defun hide-ifdef-set-define-alist (name)
"Set the association for NAME to `hide-ifdef-env'."
(interactive "SSet define list: ")
(push (cons name (hif-compress-define-list hide-ifdef-env))
hide-ifdef-define-alist))
(defun hide-ifdef-use-define-alist (name)
"Set `hide-ifdef-env' to the define list specified by NAME."
(interactive
(list (completing-read "Use define list: "
(mapcar (lambda (x) (symbol-name (car x)))
hide-ifdef-define-alist)
nil t)))
(if (stringp name) (setq name (intern name)))
(let ((define-list (assoc name hide-ifdef-define-alist)))
(if define-list
(setq hide-ifdef-env
(mapcar (lambda (arg) (cons arg t))
(cdr define-list)))
(error "No define list for %s" name))
(if hide-ifdef-hiding (hide-ifdefs))))
(provide 'hideif)
;;; hideif.el ends here