* vc.el (vc-log-show-limit): New variable.

(vc-print-log, vc-print-root-log): Add new argument LIMIT.  Set it
when using a prefix argument.
(vc-print-log-internal): Add new argument LIMIT.

* vc-svn.el (vc-svn-print-log):
* vc-mtn.el (vc-mtn-print-log):
* vc-hg.el (vc-hg-print-log):
* vc-bzr.el (vc-bzr-print-log): Add new optional argument LIMIT,
pass it to the log command when set. Make the BUFFER argument
non-optional.

* vc-sccs.el (vc-sccs-print-log):
* vc-rcs.el (vc-rcs-print-log):
* vc-git.el (vc-git-print-log):
* vc-cvs.el (vc-cvs-print-log): Add new optional argument LIMIT,
ignore it.  Make the BUFFER argument non-optional

10 files changed, 85 insertions, 34 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index c0860179da1..876e48db9fd 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,23 @@
 2009-11-15  Dan Nicolaescu  <dann@ics.uci.edu>
 
+        * vc.el (vc-log-show-limit): New variable.
+        (vc-print-log, vc-print-root-log): Add new argument LIMIT.  Set it
+        when using a prefix argument.
+        (vc-print-log-internal): Add new argument LIMIT.
+
+        * vc-svn.el (vc-svn-print-log):
+        * vc-mtn.el (vc-mtn-print-log):
+        * vc-hg.el (vc-hg-print-log):
+        * vc-bzr.el (vc-bzr-print-log): Add new optional argument LIMIT,
+        pass it to the log command when set. Make the BUFFER argument
+        non-optional.
+
+        * vc-sccs.el (vc-sccs-print-log):
+        * vc-rcs.el (vc-rcs-print-log):
+        * vc-git.el (vc-git-print-log):
+        * vc-cvs.el (vc-cvs-print-log): Add new optional argument LIMIT,
+        ignore it.  Make the BUFFER argument non-optional
+
         * bindings.el (mode-line-buffer-identification): Do not purecopy.
 
 2009-11-15  Chong Yidong  <cyd@stupidchicken.com>
diff --git a/lisp/vc-bzr.el b/lisp/vc-bzr.el
index c5d951a48f4..a40aad73597 100644
--- a/lisp/vc-bzr.el
+++ b/lisp/vc-bzr.el
@@ -481,7 +481,7 @@ REV non-nil gets an error."
                     (2 'change-log-email))
                    ("^ *timestamp: \\(.*\\)" (1 'change-log-date-face)))))))
 
-(defun vc-bzr-print-log (files &optional buffer shortlog) ; get buffer arg in Emacs 22
+(defun vc-bzr-print-log (files buffer &optional shortlog limit)
   "Get bzr change log for FILES into specified BUFFER."
   ;; `vc-do-command' creates the buffer, but we need it before running
   ;; the command.
@@ -493,7 +493,8 @@ REV non-nil gets an error."
   ;; way of getting the above regexps working.
   (with-current-buffer buffer
     (apply 'vc-bzr-command "log" buffer 'async files
-           (if shortlog "--short")
+           (when shortlog "--short")
+           (when limit (list "-l" (format "%s" limit)))
            (if (stringp vc-bzr-log-switches)
                (list vc-bzr-log-switches)
              vc-bzr-log-switches))))
diff --git a/lisp/vc-cvs.el b/lisp/vc-cvs.el
index 1cc971a58af..887804689d4 100644
--- a/lisp/vc-cvs.el
+++ b/lisp/vc-cvs.el
@@ -496,7 +496,7 @@ Will fail unless you have administrative privileges on the repo."
 
 (declare-function vc-rcs-print-log-cleanup "vc-rcs" ())
 
-(defun vc-cvs-print-log (files &optional buffer shortlog)
+(defun vc-cvs-print-log (files buffer &optional shortlog limit)
   "Get change logs associated with FILES."
   (require 'vc-rcs)
   ;; It's just the catenation of the individual logs.
diff --git a/lisp/vc-git.el b/lisp/vc-git.el
index 9f01a84cc81..c2900dd0b1c 100644
--- a/lisp/vc-git.el
+++ b/lisp/vc-git.el
@@ -77,7 +77,7 @@
 ;; - merge-news (file)                     see `merge'
 ;; - steal-lock (file &optional revision)          NOT NEEDED
 ;; HISTORY FUNCTIONS
-;; * print-log (files &optional buffer shortlog)   OK
+;; * print-log (files buffer &optional shortlog limit)   OK
 ;; - log-view-mode ()                              OK
 ;; - show-log-entry (revision)                     OK
 ;; - comment-history (file)                        ??
@@ -508,7 +508,7 @@ If nil, use the value of `vc-diff-switches'.  If t, use no switches."
 
 ;;; HISTORY FUNCTIONS
 
-(defun vc-git-print-log (files &optional buffer shortlog)
+(defun vc-git-print-log (files buffer &optional shortlog limit)
   "Get change log associated with FILES."
   (let ((coding-system-for-read git-commits-coding-system))
     ;; `vc-do-command' creates the buffer, but we need it before running
diff --git a/lisp/vc-hg.el b/lisp/vc-hg.el
index b5c55d783f6..42bdd4185e3 100644
--- a/lisp/vc-hg.el
+++ b/lisp/vc-hg.el
@@ -68,7 +68,7 @@
 ;; - merge-news (file)                         NEEDED
 ;; - steal-lock (file &optional revision)      NOT NEEDED
 ;; HISTORY FUNCTIONS
-;; * print-log (files &optional buffer shortlog)OK
+;; * print-log (files buffer &optional shortlog) OK
 ;; - log-view-mode ()                          OK
 ;; - show-log-entry (revision)                 NOT NEEDED, DEFAULT IS GOOD
 ;; - comment-history (file)                    NOT NEEDED
@@ -219,12 +219,8 @@ If nil, use the value of `vc-diff-switches'.  If t, use no switches."
                  (repeat :tag "Argument List" :value ("") string))
   :group 'vc-hg)
 
-(defun vc-hg-print-log (files &optional buffer shortlog)
+(defun vc-hg-print-log (files buffer &optional shortlog limit)
   "Get change log associated with FILES."
-  ;; `log-view-mode' needs to have the file names in order to function
-  ;; correctly. "hg log" does not print it, so we insert it here by
-  ;; hand.
-
   ;; `vc-do-command' creates the buffer, but we need it before running
   ;; the command.
   (vc-setup-buffer buffer)
@@ -234,9 +230,10 @@ If nil, use the value of `vc-diff-switches'.  If t, use no switches."
     (with-current-buffer
         buffer
       (apply 'vc-hg-command buffer 0 files "log"
-             (if shortlog
-                 (append '("--style" "compact") vc-hg-log-switches)
-                 vc-hg-log-switches)))))
+             (append
+              (when limit (list "-l" (format "%s" limit)))
+              (when shortlog '("--style" "compact"))
+              vc-hg-log-switches)))))
 
 (defvar log-view-message-re)
 (defvar log-view-file-re)
diff --git a/lisp/vc-mtn.el b/lisp/vc-mtn.el
index e03dfaad350..05be5c8ef11 100644
--- a/lisp/vc-mtn.el
+++ b/lisp/vc-mtn.el
@@ -188,8 +188,9 @@ If nil, use the value of `vc-diff-switches'.  If t, use no switches."
 ;; (defun vc-mtn-roolback (files)
 ;;   )
 
-(defun vc-mtn-print-log (files &optional buffer shortlog)
-  (vc-mtn-command buffer 0 files "log"))
+(defun vc-mtn-print-log (files buffer &optional shortlog limit)
+  (apply 'vc-mtn-command buffer 0 files "log"
+         (when limit (list "--last" (format "%s" limit)))))
 
 (defvar log-view-message-re)
 (defvar log-view-file-re)
diff --git a/lisp/vc-rcs.el b/lisp/vc-rcs.el
index ddc27e4b36c..0fa40fac824 100644
--- a/lisp/vc-rcs.el
+++ b/lisp/vc-rcs.el
@@ -559,7 +559,7 @@ directory the operation is applied to all registered files beneath it."
     (when (looking-at "[\b\t\n\v\f\r ]+")
       (delete-char (- (match-end 0) (match-beginning 0))))))
 
-(defun vc-rcs-print-log (files &optional buffer shortlog)
+(defun vc-rcs-print-log (files buffer &optional shortlog limit)
   "Get change log associated with FILE.  If FILE is a
 directory the operation is applied to all registered files beneath it."
   (vc-do-command (or buffer "*vc*") 0 "rlog" (mapcar 'vc-name (vc-expand-dirs files)))
diff --git a/lisp/vc-sccs.el b/lisp/vc-sccs.el
index e805f621d28..4c72e3be0c0 100644
--- a/lisp/vc-sccs.el
+++ b/lisp/vc-sccs.el
@@ -335,7 +335,7 @@ revert all subfiles."
 ;;; History functions
 ;;;
 
-(defun vc-sccs-print-log (files &optional buffer shortlog)
+(defun vc-sccs-print-log (files buffer &optional shortlog limit)
   "Get change log associated with FILES."
   (setq files (vc-expand-dirs files))
   (vc-sccs-do-command buffer 0 "prs" (mapcar 'vc-name files)))
diff --git a/lisp/vc-svn.el b/lisp/vc-svn.el
index ff3eef245f1..23c23e180ba 100644
--- a/lisp/vc-svn.el
+++ b/lisp/vc-svn.el
@@ -462,7 +462,7 @@ or svn+ssh://."
   (require 'add-log)
   (set (make-local-variable 'log-view-per-file-logs) nil))
 
-(defun vc-svn-print-log (files &optional buffer shortlog)
+(defun vc-svn-print-log (files buffer &optional shortlog limit)
   "Get change log(s) associated with FILES."
   (save-current-buffer
     (vc-setup-buffer buffer)
@@ -471,7 +471,8 @@ or svn+ssh://."
       (if files
           (dolist (file files)
                   (insert "Working file: " file "\n")
-                  (vc-svn-command
+                  (apply
+                   'vc-svn-command
                    buffer
                    'async
                    ;; (if (and (= (length files) 1) (vc-stay-local-p file 'SVN)) 'async 0)
@@ -481,9 +482,11 @@ or svn+ssh://."
                    ;; working revision, whereas we also want the log of the
                    ;; subsequent commits.  At least that's what the
                    ;; vc-cvs.el code does.
-                   "-rHEAD:0"))
+                   "-rHEAD:0"
+                   (when limit (list "-l" (format "%s" limit)))))
         ;; Dump log for the entire directory.
-        (vc-svn-command buffer 0 nil "log" "-rHEAD:0")))))
+        (apply vc-svn-command buffer 0 nil "log" "-rHEAD:0"
+               (when limit (list "-l" (format "%s" limit))))))))
 
 (defun vc-svn-diff (files &optional oldvers newvers buffer)
   "Get a difference report using SVN between two revisions of fileset FILES."
diff --git a/lisp/vc.el b/lisp/vc.el
index 19033c214d8..9c38d98a15a 100644
--- a/lisp/vc.el
+++ b/lisp/vc.el
@@ -333,12 +333,11 @@
 ;;
 ;; HISTORY FUNCTIONS
 ;;
-;; * print-log (files &optional buffer shortlog)
+;; * print-log (files buffer &optional shortlog limit)
 ;;
-;;   Insert the revision log for FILES into BUFFER, or the *vc* buffer
-;;   if BUFFER is nil.  (Note: older versions of this function expected
-;;   only a single file argument.)
+;;   Insert the revision log for FILES into BUFFER.
 ;;   If SHORTLOG is true insert a short version of the log.
+;;   If LIMIT is true insert only insert LIMIT log entries.
 ;;
 ;; - log-view-mode ()
 ;;
@@ -695,6 +694,13 @@ to use -L and sets this variable to remember whether it worked."
   :type '(choice (const :tag "Work out" nil) (const yes) (const no))
   :group 'vc)
 
+(defcustom vc-log-show-limit 0
+  "Limit the number of items shown by the VC log commands.
+Zero means unlimited.
+Not all VC backends are able to support this feature."
+  :type 'integer
+  :group 'vc)
+
 (defcustom vc-allow-async-revert nil
   "Specifies whether the diff during \\[vc-revert] may be asynchronous.
 Enabling this option means that you can confirm a revert operation even
@@ -1839,7 +1845,7 @@ If it contains `directory' then if the fileset contains a directory show a short
 If it contains `file' then show short logs for files.
 Not all VC backends support short logs!")
 
-(defun vc-print-log-internal (backend files working-revision)
+(defun vc-print-log-internal (backend files working-revision limit)
   ;; Don't switch to the output buffer before running the command,
   ;; so that any buffer-local settings in the vc-controlled
   ;; buffer can be accessed by the command.
@@ -1852,7 +1858,7 @@ Not all VC backends support short logs!")
           (not (null (if dir-present
                          (memq 'directory vc-log-short-style)
                        (memq 'file vc-log-short-style)))))
-    (vc-call-backend backend 'print-log files "*vc-change-log*" vc-short-log)
+    (vc-call-backend backend 'print-log files "*vc-change-log*" vc-short-log limit)
     (pop-to-buffer "*vc-change-log*")
     (vc-exec-after
      `(let ((inhibit-read-only t)
@@ -1868,20 +1874,45 @@ Not all VC backends support short logs!")
         (set-buffer-modified-p nil)))))
 
 ;;;###autoload
-(defun vc-print-log (&optional working-revision)
+(defun vc-print-log (&optional working-revision limit)
   "List the change log of the current fileset in a window.
 If WORKING-REVISION is non-nil, leave the point at that revision."
-  (interactive)
+  (interactive
+   (cond
+    (current-prefix-arg
+     (let ((rev (read-from-minibuffer "Log from revision (default: last revision): " nil
+                                      nil nil nil))
+           (lim (string-to-number
+                 (read-from-minibuffer
+                  "Limit display (unlimited: 0): "
+                  (format "%s" vc-log-show-limit)
+                  nil nil nil))))
+       (when (string= rev "") (setq rev nil))
+       (when (<= lim 0) (setq lim nil))
+       (list rev lim)))
+    (t
+     (list nil nil))))
   (let* ((vc-fileset (vc-deduce-fileset t)) ;FIXME: Why t? --Stef
          (backend (car vc-fileset))
          (files (cadr vc-fileset))
          (working-revision (or working-revision (vc-working-revision (car files)))))
-    (vc-print-log-internal backend files working-revision)))
+    (vc-print-log-internal backend files working-revision limit)))
 
 ;;;###autoload
-(defun vc-print-root-log ()
+(defun vc-print-root-log (&optional limit)
   "List the change log of for the current VC controlled tree in a window."
-  (interactive)
+  (interactive
+   (cond
+    (current-prefix-arg
+     (let ((lim (string-to-number
+                 (read-from-minibuffer
+                  "Limit display (unlimited: 0): "
+                  (format "%s" vc-log-show-limit)
+                  nil nil nil))))
+       (when (<= lim 0) (setq lim nil))
+       (list lim)))
+    (t
+     (list nil))))
   (let ((backend
          (cond ((derived-mode-p 'vc-dir-mode)  vc-dir-backend)
                (vc-mode (vc-backend buffer-file-name))))
@@ -1890,7 +1921,7 @@ If WORKING-REVISION is non-nil, leave the point at that revision."
       (error "Buffer is not version controlled"))
     (setq rootdir (vc-call-backend backend 'root default-directory))
     (setq working-revision (vc-working-revision rootdir))
-    (vc-print-log-internal backend (list rootdir) working-revision)))
+    (vc-print-log-internal backend (list rootdir) working-revision limit)))
 
 ;;;###autoload
 (defun vc-revert ()