* bindings.el (completion-ignored-extensions): Remove pdf and dvi

extensions since they can be viewed with doc-view.

* files.el (auto-mode-alist): Make doc-view-mode the default mode
for pdf, ps and dvi files.

* doc-view.el: Make doc-view-mode the standard mode for viewing
pdf, [e]ps and dvi files and add binding C-c C-c to toggle between
text and image display.  Add binding C-c C-e to switch to an
editing mode.
(doc-view-ghostscript-options, doc-view-ps->pdf): Add "-dSAFER" to
avoid security problems when rendering files untrusted sources.

4 files changed, 231 insertions, 157 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 77740d1f910..d6b0dd86cac 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,18 @@
+2007-10-17  Tassilo Horn  <tassilo@member.fsf.org>
+
+        * bindings.el (completion-ignored-extensions): Remove pdf and dvi
+        extensions since they can be viewed with doc-view.
+
+        * files.el (auto-mode-alist): Make doc-view-mode the default mode
+        for pdf, ps and dvi files.
+
+        * doc-view.el: Make doc-view-mode the standard mode for viewing
+        pdf, [e]ps and dvi files and add binding C-c C-c to toggle between
+        text and image display.  Add binding C-c C-e to switch to an
+        editing mode.
+        (doc-view-ghostscript-options, doc-view-ps->pdf): Add "-dSAFER" to
+        avoid security problems when rendering files untrusted sources.
+
 2007-10-17  Aaron Hawley  <aaronh@garden.org>
 
         * tutorial.el (tutorial--save-tutorial): Display message when tutorial
diff --git a/lisp/bindings.el b/lisp/bindings.el
index bab319fa029..5080eb8c3b0 100644
--- a/lisp/bindings.el
+++ b/lisp/bindings.el
@@ -536,7 +536,7 @@ is okay.  See `mode-line-format'.")
        '(".elc" ".lof"
          ".glo" ".idx" ".lot"
          ;; TeX-related
-         ".dvi" ".fmt" ".tfm" ".pdf"
+         ".fmt" ".tfm"
          ;; Java compiled
          ".class"
          ;; CLISP
diff --git a/lisp/doc-view.el b/lisp/doc-view.el
index 40c91ffe016..64ee1bbd8ea 100644
--- a/lisp/doc-view.el
+++ b/lisp/doc-view.el
@@ -5,7 +5,7 @@
 ;; Author: Tassilo Horn <tassilo@member.fsf.org>
 ;; Maintainer: Tassilo Horn <tassilo@member.fsf.org>
 ;; Keywords: files, pdf, ps, dvi
-;; Version: <2007-10-02 Tue 18:21>
+;; Version: <2007-10-17 Wed 22:15>
 
 ;; This file is part of GNU Emacs.
 
@@ -28,8 +28,7 @@
 
 ;; doc-view.el requires GNU Emacs 22.1 or newer.  You also need Ghostscript,
 ;; `dvipdfm' which comes with teTeX and `pdftotext', which comes with xpdf
-;; (http://www.foolabs.com/xpdf/) or poppler
-;; (http://poppler.freedesktop.org/).
+;; (http://www.foolabs.com/xpdf/) or poppler (http://poppler.freedesktop.org/).
 
 ;;; Commentary:
 
@@ -38,16 +37,19 @@
 ;; inside an Emacs buffer.  This buffer uses `doc-view-mode' which provides
 ;; convenient key bindings for browsing the document.
 ;;
-;; To use it simply do
+;; To use it simply open a document file with
 ;;
-;;     M-x doc-view RET
+;;     C-x C-f ~/path/to/document RET
 ;;
-;; and you'll be queried for a document to open.
+;; and the document will be converted and displayed, if your emacs supports png
+;; images.  With `C-c C-c' you can toggle between the rendered images
+;; representation and the source text representation of the document.  With
+;; `C-c C-e' you can switch to an appropriate editing mode for the document.
 ;;
 ;; Since conversion may take some time all the PNG images are cached in a
 ;; subdirectory of `doc-view-cache-directory' and reused when you want to view
-;; that file again.  This reusing can be omitted if you provide a prefx
-;; argument to `doc-view'.  To delete all cached files use
+;; that file again.  To reconvert a document hit `g' (`doc-view-reconvert-doc')
+;; when displaying the document.  To delete all cached files use
 ;; `doc-view-clear-cache'.  To open the cache with dired, so that you can tidy
 ;; it out use `doc-view-dired-cache'.
 ;;
@@ -68,8 +70,6 @@
 ;; bottom-right corner of the desired slice.  To reset the slice use
 ;; `doc-view-reset-slice' (bound to `s r').
 ;;
-;; Dired users should have a look at `doc-view-dired'.
-;;
 ;; You can also search within the document.  The command `doc-view-search'
 ;; (bound to `C-s') queries for a search regexp and initializes a list of all
 ;; matching pages and messages how many match-pages were found.  After that you
@@ -81,17 +81,16 @@
 ;; conversion.  When that finishes and you're still viewing the document
 ;; (i.e. you didn't switch to another buffer) you're queried for the regexp
 ;; then.
+;;
+;; Dired users can simply hit `v' on a document file.  If it's a PS, PDF or DVI
+;; it will be opened using `doc-view-mode'.
+;;
 
 ;;; Configuration:
 
-;; Basically doc-view should be quite usable with its standard settings, so
-;; putting
-;;
-;;     (require 'doc-view)
-;;
-;; into your `user-init-file' should be enough.  If the images are too small or
-;; too big you should set the "-rXXX" option in `doc-view-ghostscript-options'
-;; to another value.  (The bigger your screen, the higher the value.)
+;; If the images are too small or too big you should set the "-rXXX" option in
+;; `doc-view-ghostscript-options' to another value.  (The bigger your screen,
+;; the higher the value.)
 ;;
 ;; This and all other options can be set with the customization interface.
 ;; Simply do
@@ -123,7 +122,7 @@
 (defcustom doc-view-ghostscript-options
   '("-dNOPAUSE" "-sDEVICE=png16m" "-dTextAlphaBits=4"
     "-dBATCH" "-dGraphicsAlphaBits=4" "-dQUIET"
-    "-r100")
+    "-dSAFER" "-r100")
   "A list of options to give to ghostscript."
   :type '(sexp)
   :group 'doc-view)
@@ -202,7 +201,10 @@ has finished."
 (defvar doc-view-current-info nil
   "Only used internally.")
 
-;;;; DocView Keymap
+(defvar doc-view-current-display nil
+  "Only used internally.")
+
+;;;; DocView Keymaps
 
 (defvar doc-view-mode-map
   (let ((map (make-sparse-keymap)))
@@ -236,9 +238,26 @@ has finished."
     (define-key map (kbd "M-v")       'scroll-down)
     ;; Show the tooltip
     (define-key map (kbd "C-t")       'doc-view-show-tooltip)
+    ;; Toggle between text and image display or editing
+    (define-key map (kbd "C-c C-c")   'doc-view-toggle-display)
+    (define-key map (kbd "C-c C-e")   'doc-view-edit-doc)
+    ;; Reconvert the current document
+    (define-key map (kbd "g")         'doc-view-reconvert-doc)
     (suppress-keymap map)
     map)
-  "Keymap used by `doc-view-mode'.")
+  "Keymap used by `doc-view-mode' when displaying a doc as a set of images.")
+
+(defvar doc-view-mode-text-map
+  (let ((map (make-sparse-keymap)))
+    ;; Toggle between text and image display or editing
+    (define-key map (kbd "C-c C-c") 'doc-view-toggle-display)
+    (define-key map (kbd "C-c C-e") 'doc-view-edit-doc)
+    ;; Killing/burying the buffer (and the process)
+    (define-key map (kbd "q")         'bury-buffer)
+    (define-key map (kbd "k")         'doc-view-kill-proc-and-buffer)
+    (define-key map (kbd "C-x k")     'doc-view-kill-proc-and-buffer)
+    map)
+  "Keymap used by `doc-view-mode' when displaying a document as text.")
 
 ;;;; Navigation Commands
 
@@ -272,16 +291,16 @@ has finished."
                          (setq contexts (concat contexts "  - \"" m "\"\n")))
                        contexts)))))
     ;; Update the buffer
-    (setq inhibit-read-only t)
-    (erase-buffer)
-    (let ((beg (point)))
-      (doc-view-insert-image (nth (1- page) doc-view-current-files)
-                             :pointer 'arrow)
-      (put-text-property beg (point) 'help-echo doc-view-current-info))
-    (insert "\n" doc-view-current-info)
-    (goto-char (point-min))
-    (forward-char)
-    (setq inhibit-read-only nil)))
+    (let ((inhibit-read-only t))
+      (erase-buffer)
+      (let ((beg (point)))
+        (doc-view-insert-image (nth (1- page) doc-view-current-files)
+                               :pointer 'arrow)
+        (put-text-property beg (point) 'help-echo doc-view-current-info))
+      (insert "\n" doc-view-current-info)
+      (goto-char (point-min))
+      (forward-char))
+    (set-buffer-modified-p nil)))
 
 (defun doc-view-next-page (&optional arg)
   "Browse ARG pages forward."
@@ -318,42 +337,62 @@ has finished."
     (error (doc-view-previous-page)
            (goto-char (point-max)))))
 
+(defun doc-view-kill-proc ()
+  "Kill the current converter process."
+  (interactive)
+  (when doc-view-current-converter-process
+    (kill-process doc-view-current-converter-process))
+  (when doc-view-current-timer
+    (cancel-timer doc-view-current-timer)
+    (setq doc-view-current-timer nil))
+  (setq mode-line-process nil))
+
 (defun doc-view-kill-proc-and-buffer ()
   "Kill the current converter process and buffer."
   (interactive)
+  (doc-view-kill-proc)
   (when (eq major-mode 'doc-view-mode)
-    (when doc-view-current-converter-process
-      (kill-process doc-view-current-converter-process))
-    (when doc-view-current-timer
-      (cancel-timer doc-view-current-timer)
-      (setq doc-view-current-timer nil))
     (kill-buffer (current-buffer))))
 
 ;;;; Conversion Functions
 
-(defun doc-view-file-name-to-directory-name (file)
-  "Return the directory where the png files of FILE should be saved.
-
-It'a a subdirectory of `doc-view-cache-directory'."
+(defun doc-view-reconvert-doc (&rest args)
+  "Reconvert the current document.
+Should be invoked when the cached images aren't up-to-date."
+  (interactive)
+  (let ((inhibit-read-only t)
+        (doc doc-view-current-doc))
+    (doc-view-kill-proc)
+    ;; Clear the old cached files
+    (when (file-exists-p (doc-view-current-cache-dir))
+      (dired-delete-file (doc-view-current-cache-dir) 'always))
+    (doc-view-kill-proc-and-buffer)
+    (find-file doc)))
+
+(defun doc-view-current-cache-dir ()
+  "Return the directory where the png files of the current doc should be saved.
+It's a subdirectory of `doc-view-cache-directory'."
   (if doc-view-current-cache-dir
       doc-view-current-cache-dir
-    (file-name-as-directory
-     (concat (file-name-as-directory doc-view-cache-directory)
-             (with-temp-buffer
-               (insert-file-contents-literally file)
-               (md5 (current-buffer)))))))
+    (setq doc-view-current-cache-dir
+          (file-name-as-directory
+           (concat (file-name-as-directory doc-view-cache-directory)
+                   (let ((doc doc-view-current-doc))
+                     (with-temp-buffer
+                       (insert-file-contents-literally doc)
+                       (md5 (current-buffer)))))))))
 
 (defun doc-view-dvi->pdf-sentinel (proc event)
   "If DVI->PDF conversion was successful, convert the PDF to PNG now."
   (if (not (string-match "finished" event))
       (message "DocView: dvi->pdf process changed status to %s." event)
     (set-buffer (process-get proc 'buffer))
-    (setq doc-view-current-converter-process nil)
+    (setq doc-view-current-converter-process nil
+          mode-line-process nil)
     (message "DocView: finished conversion from DVI to PDF!")
     ;; Now go on converting this PDF to a set of PNG files.
     (let* ((pdf (process-get proc 'pdf-file))
-           (png (concat (doc-view-file-name-to-directory-name
-                         doc-view-current-doc)
+           (png (concat (doc-view-current-cache-dir)
                         "page-%d.png")))
       (doc-view-pdf/ps->png pdf png))))
 
@@ -361,9 +400,10 @@ It'a a subdirectory of `doc-view-cache-directory'."
   "Convert DVI to PDF asynchrounously."
   (message "DocView: converting DVI to PDF now!")
   (setq doc-view-current-converter-process
-        (start-process "doc-view-dvi->pdf" doc-view-conversion-buffer
+        (start-process "dvi->pdf" doc-view-conversion-buffer
                        doc-view-dvipdfm-program
-                       "-o" pdf dvi))
+                       "-o" pdf dvi)
+        mode-line-process (list (format ":%s" doc-view-current-converter-process)))
   (set-process-sentinel doc-view-current-converter-process
                         'doc-view-dvi->pdf-sentinel)
   (process-put doc-view-current-converter-process 'buffer   (current-buffer))
@@ -374,7 +414,8 @@ It'a a subdirectory of `doc-view-cache-directory'."
   (if (not (string-match "finished" event))
       (message "DocView: converter process changed status to %s." event)
     (set-buffer (process-get proc 'buffer))
-    (setq doc-view-current-converter-process nil)
+    (setq doc-view-current-converter-process nil
+          mode-line-process nil)
     (when doc-view-current-timer
       (cancel-timer doc-view-current-timer)
       (setq doc-view-current-timer nil))
@@ -387,11 +428,12 @@ It'a a subdirectory of `doc-view-cache-directory'."
   (message "DocView: converting PDF or PS to PNG now!")
   (setq doc-view-current-converter-process
         (apply 'start-process
-               (append (list "doc-view-pdf/ps->png" doc-view-conversion-buffer
+               (append (list "pdf/ps->png" doc-view-conversion-buffer
                              doc-view-ghostscript-program)
                        doc-view-ghostscript-options
                        (list (concat "-sOutputFile=" png))
-                       (list pdf-ps))))
+                       (list pdf-ps)))
+        mode-line-process (list (format ":%s" doc-view-current-converter-process)))
   (process-put doc-view-current-converter-process
                'buffer (current-buffer))
   (set-process-sentinel doc-view-current-converter-process
@@ -399,7 +441,7 @@ It'a a subdirectory of `doc-view-cache-directory'."
   (when doc-view-conversion-refresh-interval
     (setq doc-view-current-timer
           (run-at-time "1 secs" doc-view-conversion-refresh-interval
-                       'doc-view-display
+                       'doc-view-display-maybe
                        doc-view-current-doc))))
 
 (defun doc-view-pdf->txt-sentinel (proc event)
@@ -408,7 +450,8 @@ It'a a subdirectory of `doc-view-cache-directory'."
     (let ((current-buffer (current-buffer))
           (proc-buffer    (process-get proc 'buffer)))
       (set-buffer proc-buffer)
-      (setq doc-view-current-converter-process nil)
+      (setq doc-view-current-converter-process nil
+            mode-line-process nil)
       (message "DocView: finished conversion from PDF to TXT!")
       ;; If the user looks at the DocView buffer where the conversion was
       ;; performed, search anew.  This time it will be queried for a regexp.
@@ -419,9 +462,10 @@ It'a a subdirectory of `doc-view-cache-directory'."
   "Convert PDF to TXT asynchrounously."
   (message "DocView: converting PDF to TXT now!")
   (setq doc-view-current-converter-process
-        (start-process "doc-view-pdf->txt" doc-view-conversion-buffer
+        (start-process "pdf->txt" doc-view-conversion-buffer
                        doc-view-pdftotext-program "-raw"
-                       pdf txt))
+                       pdf txt)
+        mode-line-process (list (format ":%s" doc-view-current-converter-process)))
   (set-process-sentinel doc-view-current-converter-process
                         'doc-view-pdf->txt-sentinel)
   (process-put doc-view-current-converter-process 'buffer (current-buffer)))
@@ -430,65 +474,44 @@ It'a a subdirectory of `doc-view-cache-directory'."
   (if (not (string-match "finished" event))
       (message "DocView: converter process changed status to %s." event)
     (set-buffer (process-get proc 'buffer))
-    (setq doc-view-current-converter-process nil)
+    (setq doc-view-current-converter-process nil
+          mode-line-process nil)
     (message "DocView: finished conversion from PS to PDF!")
     ;; Now we can transform to plain text.
     (doc-view-pdf->txt (process-get proc 'pdf-file)
-                       (concat (doc-view-file-name-to-directory-name
-                                doc-view-current-doc)
+                       (concat (doc-view-current-cache-dir)
                                "doc.txt"))))
 
 (defun doc-view-ps->pdf (ps pdf)
   "Convert PS to PDF asynchronously."
   (message "DocView: converting PS to PDF now!")
   (setq doc-view-current-converter-process
-        (start-process "doc-view-ps->pdf" doc-view-conversion-buffer
+        (start-process "ps->pdf" doc-view-conversion-buffer
                        doc-view-ps2pdf-program
-                       ps pdf))
+                       ps pdf "-dSAFER")
+        mode-line-process (list (format ":%s" doc-view-current-converter-process)))
   (set-process-sentinel doc-view-current-converter-process
                         'doc-view-ps->pdf-sentinel)
   (process-put doc-view-current-converter-process 'buffer   (current-buffer))
   (process-put doc-view-current-converter-process 'pdf-file pdf))
 
-(defun doc-view-convert-doc (doc)
-  "Convert DOC to a set of png files, one file per page.
-
-Those files are saved in the directory given by
-`doc-view-file-name-to-directory-name'."
+(defun doc-view-convert-current-doc ()
+  "Convert `doc-view-current-doc' to a set of png files, one file per page.
+Those files are saved in the directory given by the function
+`doc-view-current-cache-dir'."
   (clear-image-cache)
-  (let* ((dir (doc-view-file-name-to-directory-name doc))
-         (png-file (concat (file-name-as-directory dir) "page-%d.png")))
-    (when (file-exists-p dir)
-      (dired-delete-file dir 'always))
-    (make-directory dir t)
-    (if (not (string= (file-name-extension doc) "dvi"))
+  (let ((png-file (concat (doc-view-current-cache-dir)
+                          "page-%d.png")))
+    (make-directory doc-view-current-cache-dir t)
+    (if (not (string= (file-name-extension doc-view-current-doc) "dvi"))
         ;; Convert to PNG images.
-        (doc-view-pdf/ps->png doc png-file)
+        (doc-view-pdf/ps->png doc-view-current-doc png-file)
       ;; DVI files have to be converted to PDF before Ghostscript can process
       ;; it.
-      (doc-view-dvi->pdf doc
-                         (concat (file-name-as-directory dir)
+      (doc-view-dvi->pdf doc-view-current-doc
+                         (concat (file-name-as-directory doc-view-current-cache-dir)
                                  "doc.pdf")))))
 
-;;;; DocView Mode
-
-(define-derived-mode doc-view-mode nil "DocView"
-  "Major mode in DocView buffers.
-
-\\{doc-view-mode-map}"
-  :group 'doc-view
-  (setq buffer-read-only t)
-  (make-local-variable 'doc-view-current-files)
-  (make-local-variable 'doc-view-current-doc)
-  (make-local-variable 'doc-view-current-image)
-  (make-local-variable 'doc-view-current-page)
-  (make-local-variable 'doc-view-current-converter-process)
-  (make-local-variable 'doc-view-current-timer)
-  (make-local-variable 'doc-view-current-slice)
-  (make-local-variable 'doc-view-current-cache-dir)
-  (make-local-variable 'doc-view-current-info)
-  (make-local-variable 'doc-view-current-search-matches))
-
 ;;;; Slicing
 
 (defun doc-view-set-slice (x y width height)
@@ -556,19 +579,22 @@ Predicate for sorting `doc-view-current-files'."
         nil
       (string< a b))))
 
+(defun doc-view-display-maybe (doc)
+  "Call `doc-view-display' iff we're in the image display."
+  (when (eq doc-view-current-display 'image)
+    (doc-view-display doc)))
+
 (defun doc-view-display (doc)
   "Start viewing the document DOC."
-  (let ((dir (doc-view-file-name-to-directory-name doc)))
-    (set-buffer (format "*DocView: %s*" doc))
-    (setq doc-view-current-files
-          (sort (directory-files dir t "page-[0-9]+\\.png" t)
-                'doc-view-sort))
-    (when (> (length doc-view-current-files) 0)
-      (doc-view-goto-page doc-view-current-page))))
+  (set-buffer (get-file-buffer doc))
+  (setq doc-view-current-files
+        (sort (directory-files (doc-view-current-cache-dir) t
+                               "page-[0-9]+\\.png" t)
+              'doc-view-sort))
+  (when (> (length doc-view-current-files) 0)
+    (doc-view-goto-page doc-view-current-page)))
 
 (defun doc-view-buffer-message ()
-  (setq inhibit-read-only t)
-  (erase-buffer)
   (insert (propertize "Welcome to DocView!" 'face 'bold)
           "\n"
           "
@@ -581,12 +607,58 @@ For now these keys are useful:
 
 `q' : Bury this buffer.  Conversion will go on in background.
 `k' : Kill the conversion process and this buffer.\n")
-  (setq inhibit-read-only nil))
+  (set-buffer-modified-p nil))
 
 (defun doc-view-show-tooltip ()
   (interactive)
   (tooltip-show doc-view-current-info))
 
+;;;;; Toggle between text and image display
+
+(defun doc-view-toggle-display ()
+  "Start or stop displaying a document file as a set of images.
+This command toggles between showing the text of the document
+file and showing the document as a set of images."
+  (interactive)
+  (if (get-text-property (point-min) 'display)
+      ;; Switch to text display
+      (let ((inhibit-read-only t))
+        (erase-buffer)
+        (insert-file-contents doc-view-current-doc)
+        (use-local-map doc-view-mode-text-map)
+        (setq mode-name "DocView[text]"
+              doc-view-current-display 'text)
+        (if (called-interactively-p)
+            (message "Repeat this command to go back to displaying the file as images")))
+    ;; Switch to image display
+    (let ((inhibit-read-only t))
+      (erase-buffer)
+      (doc-view-buffer-message)
+      (setq doc-view-current-page (or doc-view-current-page 1))
+      (if (file-exists-p (doc-view-current-cache-dir))
+          (progn
+            (message "DocView: using cached files!")
+            (doc-view-display doc-view-current-doc))
+        (doc-view-convert-current-doc))
+      (use-local-map doc-view-mode-map)
+      (setq mode-name (format "DocView")
+            doc-view-current-display 'image)
+      (if (called-interactively-p)
+          (message "Repeat this command to go back to displaying the file as text"))))
+  (set-buffer-modified-p nil))
+
+;;;;; Leave doc-view-mode and open the file for edit
+
+(defun doc-view-edit-doc ()
+  "Leave `doc-view-mode' and open the current doc with an appropriate editing mode."
+  (interactive)
+  (let ((filename doc-view-current-doc)
+        (auto-mode-alist (append '(("\\.[eE]?[pP][sS]\\'" . ps-mode)
+                                   ("\\.\\(pdf\\|PDF\\|dvi\\|DVI\\)$" . fundamental-mode))
+                                 auto-mode-alist)))
+    (kill-buffer (current-buffer))
+    (find-file filename)))
+
 ;;;; Searching
 
 (defun doc-view-search-internal (regexp file)
@@ -637,8 +709,7 @@ conversion finished."
   (interactive)
   ;; New search, so forget the old results.
   (setq doc-view-current-search-matches nil)
-  (let ((txt (concat (doc-view-file-name-to-directory-name
-                      doc-view-current-doc)
+  (let ((txt (concat (doc-view-current-cache-dir)
                      "doc.txt")))
     (if (file-readable-p txt)
         (progn
@@ -661,14 +732,12 @@ conversion finished."
             ;; Doc is a PS, so convert it to PDF (which will be converted to
             ;; TXT thereafter).
             (doc-view-ps->pdf doc-view-current-doc
-                              (concat (doc-view-file-name-to-directory-name
-                                       doc-view-current-doc)
+                              (concat (doc-view-current-cache-dir)
                                       "doc.pdf")))
            ((string= ext "dvi")
             ;; Doc is a DVI.  This means that a doc.pdf already exists in its
             ;; cache subdirectory.
-            (doc-view-pdf->txt (concat (doc-view-file-name-to-directory-name
-                                        doc-view-current-doc)
+            (doc-view-pdf->txt (concat (doc-view-current-cache-dir)
                                        "doc.pdf")
                                txt))
            (t (error "DocView doesn't know what to do"))))))))
@@ -699,52 +768,42 @@ conversion finished."
              (y-or-n-p "No more matches before current page.  Wrap to last match? "))
         (doc-view-goto-page (caar (last doc-view-current-search-matches)))))))
 
-;;;; User Interface Commands
+;;;; User interface commands and the mode
 
-;;;###autoload
-(defun doc-view (no-cache &optional file)
-  "Convert FILE to png and start viewing it.
-If no FILE is given, query for on.
-If this FILE is still in the cache, don't convert and use the
-existing page files.  With prefix arg NO-CACHE, don't use the
-cached files and convert anew."
-  (interactive "P")
-  (if (not (and (image-type-available-p 'png)
-                (display-images-p)))
-      (message "DocView: your emacs or display doesn't support png images.")
-    (let* ((doc (or file
-                    (expand-file-name
-                     (let ((completion-ignored-extensions
-                            ;; Don't hide files doc-view can display
-                            (remove-if (lambda (str)
-                                         (string-match "\\.\\(ps\\|pdf\\|dvi\\)$"
-                                                       str))
-                                       completion-ignored-extensions)))
-                       (read-file-name "File: " nil nil t)))))
-           (buffer (get-buffer-create (format "*DocView: %s*" doc)))
-           (dir (doc-view-file-name-to-directory-name doc)))
-      (switch-to-buffer buffer)
-      (doc-view-buffer-message)
-      (doc-view-mode)
-      (setq doc-view-current-doc doc)
-      (setq doc-view-current-page 1)
-      (if (not (and (file-exists-p dir)
-                    (not no-cache)))
-          (progn
-            (setq doc-view-current-cache-dir nil)
-            (doc-view-convert-doc doc-view-current-doc))
-        (message "DocView: using cached files!")
-        (doc-view-display doc-view-current-doc)))))
+(put 'doc-view-mode 'mode-class 'special)
 
-(defun doc-view-dired (no-cache)
-  "View the current dired file with doc-view.
-NO-CACHE is the same as in `doc-view'.
-
-You might want to bind this command to a dired key, e.g.
-
-    (define-key dired-mode-map (kbd \"C-c d\") 'doc-view-dired)"
-  (interactive "P")
-  (doc-view no-cache (dired-get-file-for-visit)))
+;;;###autoload
+(define-derived-mode doc-view-mode nil "DocView"
+  "Major mode in DocView buffers.
+You can use \\<doc-view-mode-map>\\[doc-view-toggle-display] to
+toggle between display as a set of images and display as text."
+  :group 'doc-view
+  (make-local-variable 'doc-view-current-files)
+  (make-local-variable 'doc-view-current-doc)
+  (make-local-variable 'doc-view-current-image)
+  (make-local-variable 'doc-view-current-page)
+  (make-local-variable 'doc-view-current-converter-process)
+  (make-local-variable 'doc-view-current-timer)
+  (make-local-variable 'doc-view-current-slice)
+  (make-local-variable 'doc-view-current-cache-dir)
+  (make-local-variable 'doc-view-current-info)
+  (make-local-variable 'doc-view-current-search-matches)
+  (setq doc-view-current-doc (buffer-file-name))
+  (insert-file-contents doc-view-current-doc)
+  (use-local-map doc-view-mode-text-map)
+  (setq mode-name "DocView[text]"
+        doc-view-current-display 'text
+        buffer-read-only t
+        revert-buffer-function 'doc-view-reconvert-doc)
+  ;; Switch to image display if possible
+  (if (and (display-images-p)
+           (image-type-available-p 'png)
+           (not (get-text-property (point-min) 'display)))
+      (doc-view-toggle-display))
+  (message
+   "%s"
+   (substitute-command-keys
+    "Type \\[doc-view-toggle-display] to toggle between image and text display.")))
 
 (defun doc-view-clear-cache ()
   "Delete the whole cache (`doc-view-cache-directory')."
diff --git a/lisp/files.el b/lisp/files.el
index be28dec4c40..3b0b670e21f 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -2059,7 +2059,7 @@ ARC\\|ZIP\\|LZH\\|LHA\\|ZOO\\|[JEW]AR\\|XPI\\|RAR\\)\\'" . archive-mode)
      ("\\.\\(as\\|mi\\|sm\\)2\\'" . snmpv2-mode)
      ("\\.\\(diffs?\\|patch\\|rej\\)\\'" . diff-mode)
      ("\\.\\(dif\\|pat\\)\\'" . diff-mode) ; for MSDOG
-     ("\\.[eE]?[pP][sS]\\'" . ps-mode)
+     ("\\(?:DVI\\|EPS\\|P\\(?:DF\\|S\\)\\|dvi\\|eps\\|p\\(?:df\\|s\\)\\)" . doc-view-mode)
      ("configure\\.\\(ac\\|in\\)\\'" . autoconf-mode)
      ("BROWSE\\'" . ebrowse-tree-mode)
      ("\\.ebrowse\\'" . ebrowse-tree-mode)