git/contrib/emacs/vc-git.el

   1 ;;; vc-git.el --- VC backend for the git version control system
   2
   3 ;; Copyright (C) 2006 Alexandre Julliard
   4
   5 ;; This program is free software; you can redistribute it and/or
   6 ;; modify it under the terms of the GNU General Public License as
   7 ;; published by the Free Software Foundation; either version 2 of
   8 ;; the License, or (at your option) any later version.
   9 ;;
  10 ;; This program is distributed in the hope that it will be
  11 ;; useful, but WITHOUT ANY WARRANTY; without even the implied
  12 ;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  13 ;; PURPOSE.  See the GNU General Public License for more details.
  14 ;;
  15 ;; You should have received a copy of the GNU General Public
  16 ;; License along with this program; if not, write to the Free
  17 ;; Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  18 ;; MA 02111-1307 USA
  19
  20 ;;; Commentary:
  21
  22 ;; This file contains a VC backend for the git version control
  23 ;; system.
  24 ;;
  25 ;; To install: put this file on the load-path and add GIT to the list
  26 ;; of supported backends in `vc-handled-backends'; the following line,
  27 ;; placed in your ~/.emacs, will accomplish this:
  28 ;;
  29 ;;     (add-to-list 'vc-handled-backends 'GIT)
  30 ;;
  31 ;; TODO
  32 ;;  - changelog generation
  33 ;;  - working with revisions other than HEAD
  34 ;;
  35
  36 (eval-when-compile (require 'cl))
  37
  38 (defvar git-commits-coding-system 'utf-8
  39   "Default coding system for git commits.")
  40
  41 (defun vc-git--run-command-string (file &rest args)
  42   "Run a git command on FILE and return its output as string."
  43   (let* ((ok t)
  44          (str (with-output-to-string
  45                 (with-current-buffer standard-output
  46                   (unless (eq 0 (apply #'call-process "git" nil '(t nil) nil
  47                                        (append args (list (file-relative-name file)))))
  48                     (setq ok nil))))))
  49     (and ok str)))
  50
  51 (defun vc-git--run-command (file &rest args)
  52   "Run a git command on FILE, discarding any output."
  53   (let ((name (file-relative-name file)))
  54     (eq 0 (apply #'call-process "git" nil (get-buffer "*Messages") nil (append args (list name))))))
  55
  56 (defun vc-git-registered (file)
  57   "Check whether FILE is registered with git."
  58   (with-temp-buffer
  59     (let* ((dir (file-name-directory file))
  60            (name (file-relative-name file dir)))
  61       (and (ignore-errors
  62              (when dir (cd dir))
  63              (eq 0 (call-process "git" nil '(t nil) nil "ls-files" "-c" "-z" "--" name)))
  64            (let ((str (buffer-string)))
  65              (and (> (length str) (length name))
  66                   (string= (substring str 0 (1+ (length name))) (concat name "\0"))))))))
  67
  68 (defun vc-git-state (file)
  69   "git-specific version of `vc-state'."
  70   (let ((diff (vc-git--run-command-string file "diff-index" "-z" "HEAD" "--")))
  71     (if (and diff (string-match ":[0-7]\\{6\\} [0-7]\\{6\\} [0-9a-f]\\{40\\} [0-9a-f]\\{40\\} [ADMU]\0[^\0]+\0" diff))
  72         'edited
  73       'up-to-date)))
  74
  75 (defun vc-git-workfile-version (file)
  76   "git-specific version of `vc-workfile-version'."
  77   (let ((str (with-output-to-string
  78                (with-current-buffer standard-output
  79                  (call-process "git" nil '(t nil) nil "symbolic-ref" "HEAD")))))
  80     (if (string-match "^\\(refs/heads/\\)?\\(.+\\)$" str)
  81         (match-string 2 str)
  82       str)))
  83
  84 (defun vc-git-symbolic-commit (commit)
  85   "Translate COMMIT string into symbolic form.
  86 Returns nil if not possible."
  87   (and commit
  88        (with-temp-buffer
  89          (and
  90           (zerop
  91            (call-process "git" nil '(t nil) nil "name-rev"
  92                          "--name-only" "--tags"
  93                          commit))
  94           (goto-char (point-min))
  95           (= (forward-line 2) 1)
  96           (bolp)
  97           (buffer-substring-no-properties (point-min) (1- (point-max)))))))
  98
  99 (defun vc-git-previous-version (file rev)
 100   "git-specific version of `vc-previous-version'."
 101   (let ((default-directory (file-name-directory (expand-file-name file)))
 102         (file (file-name-nondirectory file)))
 103     (vc-git-symbolic-commit
 104      (with-temp-buffer
 105        (and
 106         (zerop
 107          (call-process "git" nil '(t nil) nil "rev-list"
 108                        "-2" rev "--" file))
 109         (goto-char (point-max))
 110         (bolp)
 111         (zerop (forward-line -1))
 112         (not (bobp))
 113         (buffer-substring-no-properties
 114            (point)
 115            (1- (point-max))))))))
 116
 117 (defun vc-git-next-version (file rev)
 118   "git-specific version of `vc-next-version'."
 119   (let* ((default-directory (file-name-directory
 120                              (expand-file-name file)))
 121         (file (file-name-nondirectory file))
 122         (current-rev
 123          (with-temp-buffer
 124            (and
 125             (zerop
 126              (call-process "git" nil '(t nil) nil "rev-list"
 127                            "-1" rev "--" file))
 128             (goto-char (point-max))
 129             (bolp)
 130             (zerop (forward-line -1))
 131             (bobp)
 132             (buffer-substring-no-properties
 133              (point)
 134              (1- (point-max)))))))
 135     (and current-rev
 136          (vc-git-symbolic-commit
 137           (with-temp-buffer
 138             (and
 139              (zerop
 140               (call-process "git" nil '(t nil) nil "rev-list"
 141                             "HEAD" "--" file))
 142              (goto-char (point-min))
 143              (search-forward current-rev nil t)
 144              (zerop (forward-line -1))
 145              (buffer-substring-no-properties
 146               (point)
 147               (progn (forward-line 1) (1- (point))))))))))
 148
 149 (defun vc-git-revert (file &optional contents-done)
 150   "Revert FILE to the version stored in the git repository."
 151   (if contents-done
 152       (vc-git--run-command file "update-index" "--")
 153     (vc-git--run-command file "checkout" "HEAD")))
 154
 155 (defun vc-git-checkout-model (file)
 156   'implicit)
 157
 158 (defun vc-git-workfile-unchanged-p (file)
 159   (let ((sha1 (vc-git--run-command-string file "hash-object" "--"))
 160         (head (vc-git--run-command-string file "ls-tree" "-z" "HEAD" "--")))
 161     (and head
 162          (string-match "[0-7]\\{6\\} blob \\([0-9a-f]\\{40\\}\\)\t[^\0]+\0" head)
 163          (string= (car (split-string sha1 "\n")) (match-string 1 head)))))
 164
 165 (defun vc-git-register (file &optional rev comment)
 166   "Register FILE into the git version-control system."
 167   (vc-git--run-command file "update-index" "--add" "--"))
 168
 169 (defun vc-git-print-log (file &optional buffer)
 170   (let ((name (file-relative-name file))
 171         (coding-system-for-read git-commits-coding-system))
 172     (vc-do-command buffer 'async "git" name "rev-list" "--pretty" "HEAD" "--")))
 173
 174 (defun vc-git-diff (file &optional rev1 rev2 buffer)
 175   (let ((name (file-relative-name file))
 176         (buf (or buffer "*vc-diff*")))
 177     (if (and rev1 rev2)
 178         (vc-do-command buf 0 "git" name "diff-tree" "-p" rev1 rev2 "--")
 179       (vc-do-command buf 0 "git" name "diff-index" "-p" (or rev1 "HEAD") "--"))
 180     ; git-diff-index doesn't set exit status like diff does
 181     (if (vc-git-workfile-unchanged-p file) 0 1)))
 182
 183 (defun vc-git-checkin (file rev comment)
 184   (let ((coding-system-for-write git-commits-coding-system))
 185     (vc-git--run-command file "commit" "-m" comment "--only" "--")))
 186
 187 (defun vc-git-checkout (file &optional editable rev destfile)
 188   (if destfile
 189       (let ((fullname (substring
 190                        (vc-git--run-command-string file "ls-files" "-z" "--full-name" "--")
 191                        0 -1))
 192             (coding-system-for-read 'no-conversion)
 193             (coding-system-for-write 'no-conversion))
 194         (with-temp-file destfile
 195           (eq 0 (call-process "git" nil t nil "cat-file" "blob"
 196                               (concat (or rev "HEAD") ":" fullname)))))
 197     (vc-git--run-command file "checkout" (or rev "HEAD"))))
 198
 199 (defun vc-git-annotate-command (file buf &optional rev)
 200   ; FIXME: rev is ignored
 201   (let ((name (file-relative-name file)))
 202     (call-process "git" nil buf nil "blame" name)))
 203
 204 (defun vc-git-annotate-time ()
 205   (and (re-search-forward "[0-9a-f]+ (.* \\([0-9]+\\)-\\([0-9]+\\)-\\([0-9]+\\) \\([0-9]+\\):\\([0-9]+\\):\\([0-9]+\\) \\([-+0-9]+\\) +[0-9]+)" nil t)
 206        (vc-annotate-convert-time
 207         (apply #'encode-time (mapcar (lambda (match) (string-to-number (match-string match))) '(6 5 4 3 2 1 7))))))
 208
 209 ;; Not really useful since we can't do anything with the revision yet
 210 ;;(defun vc-annotate-extract-revision-at-line ()
 211 ;;  (save-excursion
 212 ;;    (move-beginning-of-line 1)
 213 ;;    (and (looking-at "[0-9a-f]+")
 214 ;;         (buffer-substring (match-beginning 0) (match-end 0)))))
 215
 216 (provide 'vc-git)