xref: /netbsd-src/external/gpl3/binutils.old/dist/binutils/dwarf-mode.el (revision fdd524d4ccd2bb0c6f67401e938dabf773eb0372)
1;;; dwarf-mode.el --- Browser for DWARF information.
2
3;; Version: 1.1
4
5;; This file is not part of GNU Emacs, but is distributed under the
6;; same terms:
7
8;; GNU Emacs is free software: you can redistribute it and/or modify
9;; it under the terms of the GNU General Public License as published by
10;; the Free Software Foundation, either version 3 of the License, or
11;; (at your option) any later version.
12
13;; GNU Emacs is distributed in the hope that it will be useful,
14;; but WITHOUT ANY WARRANTY; without even the implied warranty of
15;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16;; GNU General Public License for more details.
17
18;; You should have received a copy of the GNU General Public License
19;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
20
21;;; Code:
22
23(defvar dwarf-objdump-program "objdump")
24
25(defconst dwarf-font-lock-keywords
26  '(
27    ;; Name and linkage name.
28    ("DW_AT_[a-z_]*name\\s *: .*:\\(.*\\)\\s *$"
29     (1 font-lock-function-name-face))
30
31    ("Compilation Unit @ offset 0x[0-9a-f]+"
32     (0 font-lock-string-face))
33    ))
34
35(defvar dwarf-file nil
36  "Buffer-local variable holding the file name passed to objdump.")
37
38;; Expand a "..." to show all the child DIES.  NEW-DEPTH controls how
39;; deep to display the new dies; `nil' means display all of them.
40(defun dwarf-do-insert-substructure (new-depth die)
41  (let ((inhibit-read-only t))
42    (beginning-of-line)
43    (delete-region (point) (progn
44			     (end-of-line)
45			     (forward-char)
46			     (point)))
47    (save-excursion
48      (apply #'call-process dwarf-objdump-program nil (current-buffer) nil
49	     "-Wi" (concat "--dwarf-start=0x" die)
50	     (expand-file-name dwarf-file)
51	     (if new-depth (list (concat "--dwarf-depth="
52					 (int-to-string new-depth))))))
53    (set-buffer-modified-p nil)))
54
55(defun dwarf-insert-substructure-button (die)
56  (beginning-of-line)
57  (unless (looking-at "^ <\\([0-9]+\\)>")
58    (error "Unrecognized line."))
59  (let ((new-depth (1+ (string-to-number (match-string 1)))))
60    (dwarf-do-insert-substructure new-depth die)))
61
62(defun dwarf-insert-substructure (arg)
63  "Expand a `...' to show children of the current DIE.
64By default, expands just one level of children.
65A prefix argument means expand all children."
66  (interactive "P")
67  (beginning-of-line)
68  (unless (looking-at "^ <\\([0-9]+\\)><\\([0-9a-f]+\\)>")
69    (error "Unrecognized line."))
70  (let ((die (match-string 2)))
71    (if arg
72	(dwarf-do-insert-substructure nil die)
73      (dwarf-insert-substructure-button die))))
74
75;; Called when a button is pressed.
76;; Either follows a DIE reference, or expands a "...".
77(defun dwarf-die-button-action (button)
78  (let* ((die (button-get button 'die))
79	 ;; Note that the first number can only be decimal.
80	 (die-rx (concat "^\\s *\\(<[0-9]+>\\)?<"
81			 die ">[^<]"))
82	 (old (point))
83	 (is-ref (button-get button 'die-ref)))
84    (if is-ref
85	(progn
86	  (goto-char (point-min))
87	  (if (re-search-forward die-rx nil 'move)
88	      (push-mark old)
89	    (goto-char old)
90	    (error "Could not find DIE <0x%s>" die)))
91      (dwarf-insert-substructure-button die))))
92
93;; Button definition.
94(define-button-type 'dwarf-die-button
95  'follow-link t
96  'action #'dwarf-die-button-action)
97
98;; Helper regexp to match a DIE reference.
99(defconst dwarf-die-reference ": \\(<0x\\([0-9a-f]+\\)>\\)\\s *$")
100
101;; Helper regexp to match a `...' indicating that there are hidden
102;; children.
103(defconst dwarf-die-more "^ <[0-9]+><\\([0-9a-z]+\\)>: \\([.][.][.]\\)")
104
105;; jit-lock callback function to fontify a region.  This applies the
106;; buttons, since AFAICT there is no good way to apply buttons via
107;; font-lock.
108(defun dwarf-fontify-region (start end)
109  (save-excursion
110    (let ((beg-line (progn (goto-char start) (line-beginning-position)))
111	  (end-line (progn (goto-char end) (line-end-position))))
112      (goto-char beg-line)
113      (while (re-search-forward dwarf-die-reference end-line 'move)
114	(let ((b-start (match-beginning 1))
115	      (b-end (match-end 1))
116	      (hex (match-string-no-properties 2)))
117	  (make-text-button b-start b-end :type 'dwarf-die-button
118			    'die hex 'die-ref t)))
119      ;; This is a bogus approach.  Why can't we make buttons from the
120      ;; font-lock defaults?
121      (goto-char beg-line)
122      (while (re-search-forward dwarf-die-more end-line 'move)
123	(let ((hex (match-string-no-properties 1))
124	      (b-start (match-beginning 2))
125	      (b-end (match-end 2)))
126	  (make-text-button b-start b-end :type 'dwarf-die-button
127			    'die hex 'die-ref nil))))))
128
129;; Run objdump and insert the contents into the buffer.  The arguments
130;; are the way they are because this is also called as a
131;; revert-buffer-function.
132(defun dwarf-do-refresh (&rest ignore)
133  (let ((inhibit-read-only t))
134    (erase-buffer)
135    (save-excursion
136      (call-process dwarf-objdump-program
137		    nil (current-buffer) nil
138		    "-Wi" "--dwarf-depth=1"
139		    (expand-file-name dwarf-file)))
140    (set-buffer-modified-p nil)))
141
142;;;###autoload
143(define-derived-mode dwarf-mode special-mode "DWARF"
144  "Major mode for browsing DWARF output.
145
146\\{dwarf-mode-map}"
147
148  (set (make-local-variable 'font-lock-defaults) '(dwarf-font-lock-keywords))
149  ;; FIXME: we could be smarter and check the file time.
150  (set (make-local-variable 'revert-buffer-function) #'dwarf-do-refresh)
151  (jit-lock-register #'dwarf-fontify-region))
152
153(define-key dwarf-mode-map [(control ?m)] #'dwarf-insert-substructure)
154
155;;;###autoload
156(defun dwarf-browse (file)
157  "Invoke `objdump' and put output into a `dwarf-mode' buffer.
158This is the main interface to `dwarf-mode'."
159  (interactive "fFile name: ")
160  (let* ((base-name (file-name-nondirectory file))
161	 (buffer (generate-new-buffer (concat "*DWARF for " base-name "*"))))
162    (pop-to-buffer buffer)
163    (dwarf-mode)
164    (set (make-local-variable 'dwarf-file) file)
165    (dwarf-do-refresh)))
166
167(provide 'dwarf-mode)
168
169;;; dwarf-mode.el ends here
170