(Info-find-node, Info-insert-subfile): Do the right thing if info files have

been compressed or gzipped.  This is saving me lots of disk space.

diff --git a/lisp/info.el b/lisp/info.el
index 7ae7542ee0aaaffead48816776bda27e977a1022..672043a0fa342333e8c7330fd4689d7fdb1afbbd 100644 (file)
--- a/lisp/info.el
+++ b/lisp/info.el
@@ -67,6 +67,41 @@ or nil if current info file is not split into subfiles.")
   "Marker pointing at beginning of current Info file's tag table.
 Marker points nowhere if file has no tag table.")
 
+(defvar Info-index-alternatives nil
+  "List of possible matches for last Info-index command.")
+
+(defvar Info-suffix-list '( (""        . nil)
+                           (".info"   . nil)
+                           (".Z"      . "uncompress")
+                           (".Y"      . "unyabba")
+                           (".z"      . "gunzip")
+                           (".info.Z" . "uncompress")
+                           (".info.Y" . "unyabba")
+                           (".z"      . "gunzip"))
+  "List of file name suffixes and associated decoding commands.
+Each entry should be (SUFFIX . STRING); the file is given to
+the command as standard input.  If STRING is nil, no decoding is done.")
+
+(defun info-insert-file-contents (filename &optional visit)
+  "Insert the contents of an info file in the current buffer.
+Do the right thing if the file has been compressed or zipped."
+  (if (null (catch 'ok
+             (mapcar
+              (function
+               (lambda (x)
+                 (let ((compressed (concat filename (car x))))
+                   (if (file-exists-p compressed)
+                       (progn
+                         (insert-file-contents compressed visit)
+                         (if (cdr x)
+                             (let ((buffer-read-only nil))
+                               (shell-command-on-region
+                                (point-min) (point-max) (cdr x) t)))
+                         (throw 'ok t))))))
+              Info-suffix-list)
+             nil))
+      (error "Can't find %s or any compressed version of it!" filename)))
+
 ;;;###autoload
 (defun info (&optional file)
   "Enter Info, the documentation browser.
@@ -118,15 +153,19 @@ to read a file name from the minibuffer."
              (setq temp-downcase
                    (expand-file-name (downcase filename) (car dirs)))
              ;; Try several variants of specified name.
-             ;; Try downcasing, appending `.info', or both.
-             (cond ((file-exists-p temp)
-                    (setq found temp))
-                   ((file-exists-p temp-downcase)
-                    (setq found temp-downcase))
-                   ((file-exists-p (concat temp ".info"))
-                    (setq found (concat temp ".info")))
-                   ((file-exists-p (concat temp-downcase ".info"))
-                    (setq found (concat temp-downcase ".info"))))
+             (catch 'foundit
+               (mapcar
+                (function
+                 (lambda (x)
+                   (if (file-exists-p (concat temp (car x)))
+                       (progn
+                         (setq found temp)
+                         (throw 'foundit nil)))
+                   (if (file-exists-p (concat temp-downcase (car x)))
+                       (progn
+                         (setq found temp-downcase)
+                         (throw 'foundit nil)))))
+                Info-suffix-list))
              (setq dirs (cdr dirs)))))
        (if found
            (setq filename found)
@@ -151,11 +190,12 @@ to read a file name from the minibuffer."
            (let ((buffer-read-only nil))
              (setq Info-current-file nil
                    Info-current-subfile nil
+                   Info-index-alternatives nil
                    buffer-file-name nil)
              (erase-buffer)
              (if (eq filename t)
                  (Info-insert-dir)
-               (insert-file-contents filename t)
+               (info-insert-file-contents filename t)
                (setq default-directory (file-name-directory filename)))
              (set-buffer-modified-p nil)
              ;; See whether file has a tag table.  Record the location if yes.
@@ -381,7 +421,7 @@ to read a file name from the minibuffer."
          (setq buffer-file-name nil)
          (widen)
          (erase-buffer)
-         (insert-file-contents lastfilename)
+         (info-insert-file-contents lastfilename)
          (set-buffer-modified-p nil)
          (setq Info-current-subfile lastfilename)))
     (goto-char (point-min))
@@ -870,6 +910,98 @@ N is the digit argument used to invoke this command."
       (scroll-down))
   )
 
+(defun Info-index (topic)
+  "Look up a string in the index for this file.
+The index is defined as the first node in the top-level menu whose
+name contains the word \"Index\", plus any immediately following
+nodes whose names also contain the word \"Index\".
+If there are no exact matches to the specified topic, this chooses
+the first match which is a case-insensitive substring of a topic.
+Use the `,' command to see the other matches.
+Give a blank topic name to go to the Index node itself."
+  (interactive "sIndex topic: ")
+  (let ((orignode Info-current-node)
+       (rnode nil)
+       (pattern (format "\n\\* \\([^\n:]*%s[^\n:]*\\):[ \t]*\\([^.\n]*\\)\\.[ t]*\\([0-9]*\\)"
+                        (regexp-quote topic)))
+       node)
+    (Info-goto-node "Top")
+    (or (search-forward "\n* menu:" nil t)
+       (error "No index"))
+    (or (re-search-forward "\n\\* \\(.*\\<Index\\>\\)" nil t)
+       (error "No index"))
+    (goto-char (match-beginning 1))
+    (let ((Info-keeping-history nil))
+      (Info-goto-node (Info-extract-menu-node-name)))
+    (or (equal topic "")
+       (let ((matches nil)
+             (exact nil)
+             (Info-keeping-history nil)
+             found)
+         (while
+             (progn
+               (goto-char (point-min))
+               (while (re-search-forward pattern nil t)
+                 (setq matches
+                       (cons (list (buffer-substring (match-beginning 1)
+                                                     (match-end 1))
+                                   (buffer-substring (match-beginning 2)
+                                                     (match-end 2))
+                                   Info-current-node
+                                   (string-to-int (concat "0"
+                                                          (buffer-substring
+                                                           (match-beginning 3)
+                                                           (match-end 3)))))
+                             matches)))
+               (and (setq node (Info-extract-pointer "next" t))
+                    (string-match "\\<Index\\>" node)))
+           (Info-goto-node node))
+         (or matches
+             (progn
+               (Info-last)
+               (error "No \"%s\" in index" topic)))
+         ;; Here it is a feature that assoc is case-sensitive.
+         (while (setq found (assoc topic matches))
+           (setq exact (cons found exact)
+                 matches (delq found matches)))
+         (setq Info-index-alternatives (nconc exact (nreverse matches)))
+         (Info-index-next 0)))))
+
+(defun Info-index-next (num)
+  "Go to the next matching index item from the last `i' command."
+  (interactive "p")
+  (or Info-index-alternatives
+      (error "No previous `i' command in this file"))
+  (while (< num 0)
+    (setq num (+ num (length Info-index-alternatives))))
+  (while (> num 0)
+    (setq Info-index-alternatives
+         (nconc (cdr Info-index-alternatives)
+                (list (car Info-index-alternatives)))
+         num (1- num)))
+  (Info-goto-node (nth 1 (car Info-index-alternatives)))
+  (if (> (nth 3 (car Info-index-alternatives)) 0)
+      (forward-line (nth 3 (car Info-index-alternatives)))
+    (forward-line 3)  ; don't search in headers
+    (let ((name (car (car Info-index-alternatives))))
+      (if (or (re-search-forward (format
+                                 "\\(Function\\|Command\\): %s\\( \\|$\\)"
+                                 (regexp-quote name)) nil t)
+             (search-forward (format "`%s'" name) nil t)
+             (and (string-match "\\`.*\\( (.*)\\)\\'" name)
+                  (search-forward
+                   (format "`%s'" (substring name 0 (match-beginning 1)))
+                   nil t))
+             (search-forward name nil t))
+         (beginning-of-line)
+       (goto-char (point-min)))))
+  (message "Found \"%s\" in %s.  %s"
+          (car (car Info-index-alternatives))
+          (nth 2 (car Info-index-alternatives))
+          (if (cdr Info-index-alternatives)
+              "(Press `,' for more)"
+            "(Only match)")))
+
 (defun Info-undefined ()
   "Make command be undefined in Info."
   (interactive)
@@ -991,13 +1123,16 @@ At end of the node's text, moves to the next node."
   (define-key Info-mode-map "f" 'Info-follow-reference)
   (define-key Info-mode-map "g" 'Info-goto-node)
   (define-key Info-mode-map "h" 'Info-help)
+  (define-key Info-mode-map "i" 'Info-index)
   (define-key Info-mode-map "l" 'Info-last)
   (define-key Info-mode-map "m" 'Info-menu)
   (define-key Info-mode-map "n" 'Info-next)
   (define-key Info-mode-map "p" 'Info-prev)
   (define-key Info-mode-map "q" 'Info-exit)
   (define-key Info-mode-map "s" 'Info-search)
+  (define-key Info-mode-map "t" 'Info-top)
   (define-key Info-mode-map "u" 'Info-up)
+  (define-key Info-mode-map "," 'Info-index-next)
   (define-key Info-mode-map "\177" 'Info-scroll-down)
   (define-key Info-mode-map [mouse-3] 'Info-follow-nearest-node)
   )
@@ -1023,6 +1158,8 @@ Selecting other nodes:
 \\[Info-directory]     Go to the Info directory node.
 \\[Info-follow-reference]      Follow a cross reference.  Reads name of reference.
 \\[Info-last]  Move to the last node you were at.
+\\[Info-index] Look up a topic in this file's Index and move to that node.
+\\[Info-index-next]    (comma) Move to the next match from a previous `i' command.
 
 Moving within a node:
 \\[scroll-up]  Normally, scroll forward a full screen.  If the end of the buffer is
@@ -1056,6 +1193,7 @@ Advanced commands:
   (make-local-variable 'Info-current-node)
   (make-local-variable 'Info-tag-table-marker)
   (make-local-variable 'Info-history)
+  (make-local-variable 'Info-index-alternatives)
   (Info-set-mode-line)
   (run-hooks 'Info-mode-hook))