binutils/dwarf-mode.el - binutils-gdb - Git at Google

 ;;; dwarf-mode.el --- Browser for DWARF information. -*-lexical-binding:t-*-

 ;; Version: 1.9

 ;; Copyright (C) 2012-2025 Free Software Foundation, Inc.

 ;; This file is not part of GNU Emacs, but is distributed under the
 ;; same terms:

 ;; 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 <http://www.gnu.org/licenses/>.

 ;;; Code:

 (defvar dwarf-objdump-program "objdump")

 (defconst dwarf-font-lock-keywords
   '(
     ;; Name and linkage name.
     ("DW_AT_[a-zA-Z_]*name\\s *:\\(?:\\s *(.*):\\)?\\s *\\(.*\\)\\s *$"
      (1 font-lock-function-name-face))

     ("Compilation Unit @ offset \\(0x[0-9a-f]+\\|0\\)"
      (0 font-lock-string-face))
     ))

 (defvar dwarf-file nil
   "Buffer-local variable holding the file name passed to objdump.")

 (defvar dwarf--process nil
   "Running objdump process, or nil.")

 (defvar dwarf--deletion-region nil
   "Region to delete before inserting text in `dwarf--filter'.")

 (defun dwarf--check-running ()
   "Throw an exception if an objdump process is already running."
   (when dwarf--process
     (error "An objdump process is still running in this buffer")))

 (defun dwarf--filter (proc string)
   "Filter function for objdump processes."
   (when (buffer-live-p (process-buffer proc))
     (with-current-buffer (process-buffer proc)
       (save-excursion
 	(let ((inhibit-read-only t))
 	  (when dwarf--deletion-region
 	    (apply #'delete-region dwarf--deletion-region)
 	    (setq dwarf--deletion-region nil))
           (goto-char (process-mark proc))
           (insert string)
           (set-marker (process-mark proc) (point))
 	  (set-buffer-modified-p nil))))))

 (defun dwarf--sentinel (proc _status)
   (when (buffer-live-p (process-buffer proc))
     (with-current-buffer (process-buffer proc)
       (setq mode-line-process nil)
       (setq dwarf--process nil))))

 (defun dwarf--invoke (start end &rest command)
   "Invoke a command and arrange to insert output into the current buffer."
   (setq mode-line-process "[Running]")
   (setq dwarf--deletion-region (list start end))
   (setq dwarf--process (make-process :name "objdump"
 				     :buffer (current-buffer)
 				     :command command
 				     :connection-type 'pipe
 				     :noquery t
 				     :filter #'dwarf--filter
 				     :sentinel #'dwarf--sentinel))
   (set-marker (process-mark dwarf--process) (point)))

 ;; Expand a "..." to show all the child DIES.  NEW-DEPTH controls how
 ;; deep to display the new dies; `nil' means display all of them.
 (defun dwarf-do-insert-substructure (new-depth die)
   (dwarf--check-running)
   (let ((inhibit-read-only t))
     (beginning-of-line)
     (apply #'dwarf--invoke
 	   (point) (save-excursion
 		     (end-of-line)
 		     (forward-char)
 		     (point))
 	   dwarf-objdump-program "-Wi" (concat "--dwarf-start=0x" die)
 	   (expand-file-name dwarf-file)
 	   (if new-depth (list (concat "--dwarf-depth="
 				       (int-to-string new-depth)))))
     (set-buffer-modified-p nil)))

 (defun dwarf-insert-substructure-button (die)
   (beginning-of-line)
   (unless (looking-at "^ <\\([0-9]+\\)>")
     (error "Unrecognized line."))
   (let ((new-depth (1+ (string-to-number (match-string 1)))))
     (dwarf-do-insert-substructure new-depth die)))

 (defun dwarf-insert-substructure (arg)
   "Expand a `...' to show children of the current DIE.
 By default, expands just one level of children.
 A prefix argument means expand all children."
   (interactive "P")
   (beginning-of-line)
   (unless (looking-at "^ <\\([0-9]+\\)><\\([0-9a-f]+\\)>: \\.\\.\\.")
     (error "Unrecognized line."))
   (let ((die (match-string 2)))
     (if arg
 	(dwarf-do-insert-substructure nil die)
       (dwarf-insert-substructure-button die))))

 ;; Called when a button is pressed.
 ;; Either follows a DIE reference, or expands a "...".
 (defun dwarf-die-button-action (button)
   (let* ((die (button-get button 'die))
 	 ;; Note that the first number can only be decimal.  It is
 	 ;; included in this search because otherwise following a ref
 	 ;; might lead to a zero-length boolean attribute in the
 	 ;; previous DIE.
 	 (die-rx (concat "^\\s *<[0-9]+><" die ">:"))
 	 (old (point))
 	 (is-ref (button-get button 'die-ref)))
     (if is-ref
 	(progn
 	  (goto-char (point-min))
 	  (if (re-search-forward die-rx nil 'move)
 	      (push-mark old)
 	    (goto-char old)
 	    (error "Could not find DIE <0x%s>" die)))
       (dwarf-insert-substructure-button die))))

 ;; Button definition.
 (define-button-type 'dwarf-die-button
   'follow-link t
   'action #'dwarf-die-button-action)

 ;; Helper regexp to match a DIE reference.
 (defconst dwarf-die-reference "\\(<0x\\([0-9a-f]+\\)>\\)")

 ;; Helper regexp to match a `...' indicating that there are hidden
 ;; children.
 (defconst dwarf-die-more "^ <[0-9]+><\\([0-9a-z]+\\)>: \\([.][.][.]\\)")

 ;; jit-lock callback function to fontify a region.  This applies the
 ;; buttons, since AFAICT there is no good way to apply buttons via
 ;; font-lock.
 (defun dwarf-fontify-region (start end)
   (save-excursion
     (let ((beg-line (progn (goto-char start) (line-beginning-position)))
 	  (end-line (progn (goto-char end) (line-end-position))))
       (goto-char beg-line)
       (while (re-search-forward dwarf-die-reference end-line 'move)
 	(let ((b-start (match-beginning 1))
 	      (b-end (match-end 1))
 	      (hex (match-string-no-properties 2)))
 	  (make-text-button b-start b-end :type 'dwarf-die-button
 			    'die hex 'die-ref t)))
       ;; This is a bogus approach.  Why can't we make buttons from the
       ;; font-lock defaults?
       (goto-char beg-line)
       (while (re-search-forward dwarf-die-more end-line 'move)
 	(let ((hex (match-string-no-properties 1))
 	      (b-start (match-beginning 2))
 	      (b-end (match-end 2)))
 	  (make-text-button b-start b-end :type 'dwarf-die-button
 			    'die hex 'die-ref nil))))))

 ;; Run objdump and insert the contents into the buffer.  The arguments
 ;; are the way they are because this is also called as a
 ;; revert-buffer-function.
 (defun dwarf-do-refresh (&rest _ignore)
   (dwarf--check-running)
   (let ((inhibit-read-only t))
     (dwarf--invoke (point-min) (point-max)
 		   dwarf-objdump-program "-Wi" "--dwarf-depth=1"
 		   (expand-file-name dwarf-file))
     (set-buffer-modified-p nil)))

 (defun dwarf-refresh-all ()
   "Refresh the current buffer without eliding substructure.
 Note that this can result in very voluminous output."
   (interactive)
   (dwarf--check-running)
   (let ((inhibit-read-only t))
     (dwarf--invoke (point-min) (point-max)
 		   dwarf-objdump-program "-Wi"
 		   (expand-file-name dwarf-file))
     (set-buffer-modified-p nil)))

 (defvar dwarf-mode-syntax-table
   (let ((table (make-syntax-table)))
     ;; This at least makes it so mark-sexp on some hex digits inside
     ;; <...> does not also copy the ">".
     (modify-syntax-entry ?< "(>" table)
     (modify-syntax-entry ?> ")<" table)
     table)
   "Syntax table for dwarf-mode buffers.")

 (defvar dwarf-mode-map
   (let ((map (make-sparse-keymap)))
     (set-keymap-parent map special-mode-map)
     (define-key map [(control ?m)] #'dwarf-insert-substructure)
     (define-key map "A" #'dwarf-refresh-all)
     map)
   "Keymap for dwarf-mode buffers.")

 (define-derived-mode dwarf-mode special-mode "DWARF"
   "Major mode for browsing DWARF output.

 \\{dwarf-mode-map}"

   (set (make-local-variable 'font-lock-defaults) '(dwarf-font-lock-keywords))
   (set (make-local-variable 'revert-buffer-function) #'dwarf-do-refresh)
   (jit-lock-register #'dwarf-fontify-region))

 ;;;###autoload
 (defun dwarf-browse (file)
   "Invoke `objdump' and put output into a `dwarf-mode' buffer.
 This is the main interface to `dwarf-mode'."
   (interactive "fFile name: ")
   (let* ((base-name (file-name-nondirectory file))
 	 (buffer (generate-new-buffer (concat "*DWARF for " base-name "*"))))
     (pop-to-buffer buffer)
     (dwarf-mode)
     (setq default-directory (file-name-directory file))
     (set (make-local-variable 'dwarf-file) file)
     (set (make-local-variable 'dwarf--process) nil)
     (set (make-local-variable 'dwarf--deletion-region) nil)
     (dwarf-do-refresh)))

 (provide 'dwarf-mode)

 ;;; dwarf-mode.el ends here
	;;; dwarf-mode.el --- Browser for DWARF information. --lexical-binding:t--

	;; Version: 1.9

	;; Copyright (C) 2012-2025 Free Software Foundation, Inc.

	;; This file is not part of GNU Emacs, but is distributed under the
	;; same terms:

	;; 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 <http://www.gnu.org/licenses/>.

	;;; Code:

	(defvar dwarf-objdump-program "objdump")

	(defconst dwarf-font-lock-keywords
	'(
	;; Name and linkage name.
	("DW_AT_[a-zA-Z_]name\\s :\\(?:\\s (.):\\)?\\s \\(.\\)\\s *$"
	(1 font-lock-function-name-face))

	("Compilation Unit @ offset \\(0x[0-9a-f]+\\\|0\\)"
	(0 font-lock-string-face))
	))

	(defvar dwarf-file nil
	"Buffer-local variable holding the file name passed to objdump.")

	(defvar dwarf--process nil
	"Running objdump process, or nil.")

	(defvar dwarf--deletion-region nil
	"Region to delete before inserting text in `dwarf--filter'.")

	(defun dwarf--check-running ()
	"Throw an exception if an objdump process is already running."
	(when dwarf--process
	(error "An objdump process is still running in this buffer")))

	(defun dwarf--filter (proc string)
	"Filter function for objdump processes."
	(when (buffer-live-p (process-buffer proc))
	(with-current-buffer (process-buffer proc)
	(save-excursion
	(let ((inhibit-read-only t))
	(when dwarf--deletion-region
	(apply #'delete-region dwarf--deletion-region)
	(setq dwarf--deletion-region nil))
	(goto-char (process-mark proc))
	(insert string)
	(set-marker (process-mark proc) (point))
	(set-buffer-modified-p nil))))))

	(defun dwarf--sentinel (proc _status)
	(when (buffer-live-p (process-buffer proc))
	(with-current-buffer (process-buffer proc)
	(setq mode-line-process nil)
	(setq dwarf--process nil))))

	(defun dwarf--invoke (start end &rest command)
	"Invoke a command and arrange to insert output into the current buffer."
	(setq mode-line-process "[Running]")
	(setq dwarf--deletion-region (list start end))
	(setq dwarf--process (make-process :name "objdump"
	:buffer (current-buffer)
	:command command
	:connection-type 'pipe
	:noquery t
	:filter #'dwarf--filter
	:sentinel #'dwarf--sentinel))
	(set-marker (process-mark dwarf--process) (point)))

	;; Expand a "..." to show all the child DIES. NEW-DEPTH controls how
	;; deep to display the new dies; `nil' means display all of them.
	(defun dwarf-do-insert-substructure (new-depth die)
	(dwarf--check-running)
	(let ((inhibit-read-only t))
	(beginning-of-line)
	(apply #'dwarf--invoke
	(point) (save-excursion
	(end-of-line)
	(forward-char)
	(point))
	dwarf-objdump-program "-Wi" (concat "--dwarf-start=0x" die)
	(expand-file-name dwarf-file)
	(if new-depth (list (concat "--dwarf-depth="
	(int-to-string new-depth)))))
	(set-buffer-modified-p nil)))

	(defun dwarf-insert-substructure-button (die)
	(beginning-of-line)
	(unless (looking-at "^ <\\([0-9]+\\)>")
	(error "Unrecognized line."))
	(let ((new-depth (1+ (string-to-number (match-string 1)))))
	(dwarf-do-insert-substructure new-depth die)))

	(defun dwarf-insert-substructure (arg)
	"Expand a `...' to show children of the current DIE.
	By default, expands just one level of children.
	A prefix argument means expand all children."
	(interactive "P")
	(beginning-of-line)
	(unless (looking-at "^ <\\([0-9]+\\)><\\([0-9a-f]+\\)>: \\.\\.\\.")
	(error "Unrecognized line."))
	(let ((die (match-string 2)))
	(if arg
	(dwarf-do-insert-substructure nil die)
	(dwarf-insert-substructure-button die))))

	;; Called when a button is pressed.
	;; Either follows a DIE reference, or expands a "...".
	(defun dwarf-die-button-action (button)
	(let* ((die (button-get button 'die))
	;; Note that the first number can only be decimal. It is
	;; included in this search because otherwise following a ref
	;; might lead to a zero-length boolean attribute in the
	;; previous DIE.
	(die-rx (concat "^\\s *<[0-9]+><" die ">:"))
	(old (point))
	(is-ref (button-get button 'die-ref)))
	(if is-ref
	(progn
	(goto-char (point-min))
	(if (re-search-forward die-rx nil 'move)
	(push-mark old)
	(goto-char old)
	(error "Could not find DIE <0x%s>" die)))
	(dwarf-insert-substructure-button die))))

	;; Button definition.
	(define-button-type 'dwarf-die-button
	'follow-link t
	'action #'dwarf-die-button-action)

	;; Helper regexp to match a DIE reference.
	(defconst dwarf-die-reference "\\(<0x\\([0-9a-f]+\\)>\\)")

	;; Helper regexp to match a `...' indicating that there are hidden
	;; children.
	(defconst dwarf-die-more "^ <[0-9]+><\\([0-9a-z]+\\)>: \\([.][.][.]\\)")

	;; jit-lock callback function to fontify a region. This applies the
	;; buttons, since AFAICT there is no good way to apply buttons via
	;; font-lock.
	(defun dwarf-fontify-region (start end)
	(save-excursion
	(let ((beg-line (progn (goto-char start) (line-beginning-position)))
	(end-line (progn (goto-char end) (line-end-position))))
	(goto-char beg-line)
	(while (re-search-forward dwarf-die-reference end-line 'move)
	(let ((b-start (match-beginning 1))
	(b-end (match-end 1))
	(hex (match-string-no-properties 2)))
	(make-text-button b-start b-end :type 'dwarf-die-button
	'die hex 'die-ref t)))
	;; This is a bogus approach. Why can't we make buttons from the
	;; font-lock defaults?
	(goto-char beg-line)
	(while (re-search-forward dwarf-die-more end-line 'move)
	(let ((hex (match-string-no-properties 1))
	(b-start (match-beginning 2))
	(b-end (match-end 2)))
	(make-text-button b-start b-end :type 'dwarf-die-button
	'die hex 'die-ref nil))))))

	;; Run objdump and insert the contents into the buffer. The arguments
	;; are the way they are because this is also called as a
	;; revert-buffer-function.
	(defun dwarf-do-refresh (&rest _ignore)
	(dwarf--check-running)
	(let ((inhibit-read-only t))
	(dwarf--invoke (point-min) (point-max)
	dwarf-objdump-program "-Wi" "--dwarf-depth=1"
	(expand-file-name dwarf-file))
	(set-buffer-modified-p nil)))

	(defun dwarf-refresh-all ()
	"Refresh the current buffer without eliding substructure.
	Note that this can result in very voluminous output."
	(interactive)
	(dwarf--check-running)
	(let ((inhibit-read-only t))
	(dwarf--invoke (point-min) (point-max)
	dwarf-objdump-program "-Wi"
	(expand-file-name dwarf-file))
	(set-buffer-modified-p nil)))

	(defvar dwarf-mode-syntax-table
	(let ((table (make-syntax-table)))
	;; This at least makes it so mark-sexp on some hex digits inside
	;; <...> does not also copy the ">".
	(modify-syntax-entry ?< "(>" table)
	(modify-syntax-entry ?> ")<" table)
	table)
	"Syntax table for dwarf-mode buffers.")

	(defvar dwarf-mode-map
	(let ((map (make-sparse-keymap)))
	(set-keymap-parent map special-mode-map)
	(define-key map [(control ?m)] #'dwarf-insert-substructure)
	(define-key map "A" #'dwarf-refresh-all)
	map)
	"Keymap for dwarf-mode buffers.")

	(define-derived-mode dwarf-mode special-mode "DWARF"
	"Major mode for browsing DWARF output.

	\\{dwarf-mode-map}"

	(set (make-local-variable 'font-lock-defaults) '(dwarf-font-lock-keywords))
	(set (make-local-variable 'revert-buffer-function) #'dwarf-do-refresh)
	(jit-lock-register #'dwarf-fontify-region))

	;;;###autoload
	(defun dwarf-browse (file)
	"Invoke `objdump' and put output into a `dwarf-mode' buffer.
	This is the main interface to `dwarf-mode'."
	(interactive "fFile name: ")
	(let* ((base-name (file-name-nondirectory file))
	(buffer (generate-new-buffer (concat "DWARF for " base-name ""))))
	(pop-to-buffer buffer)
	(dwarf-mode)
	(setq default-directory (file-name-directory file))
	(set (make-local-variable 'dwarf-file) file)
	(set (make-local-variable 'dwarf--process) nil)
	(set (make-local-variable 'dwarf--deletion-region) nil)
	(dwarf-do-refresh)))

	(provide 'dwarf-mode)

	;;; dwarf-mode.el ends here