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-revert (file &optional contents-done)
85 "Revert FILE to the version stored in the git repository."
86 (if contents-done
87 (vc-git--run-command file "update-index" "--")
88 (vc-git--run-command file "checkout" "HEAD")))
89
90(defun vc-git-checkout-model (file)
91 'implicit)
92
93(defun vc-git-workfile-unchanged-p (file)
94 (let ((sha1 (vc-git--run-command-string file "hash-object" "--"))
95 (head (vc-git--run-command-string file "ls-tree" "-z" "HEAD" "--")))
96 (and head
97 (string-match "[0-7]\\{6\\} blob \\([0-9a-f]\\{40\\}\\)\t[^\0]+\0" head)
98 (string= (car (split-string sha1 "\n")) (match-string 1 head)))))
99
100(defun vc-git-register (file &optional rev comment)
101 "Register FILE into the git version-control system."
102 (vc-git--run-command file "update-index" "--add" "--"))
103
104(defun vc-git-print-log (file &optional buffer)
105 (let ((name (file-relative-name file))
106 (coding-system-for-read git-commits-coding-system))
107 (vc-do-command buffer 'async "git" name "rev-list" "--pretty" "HEAD" "--")))
108
109(defun vc-git-diff (file &optional rev1 rev2 buffer)
110 (let ((name (file-relative-name file))
111 (buf (or buffer "*vc-diff*")))
112 (if (and rev1 rev2)
113 (vc-do-command buf 0 "git" name "diff-tree" "-p" rev1 rev2 "--")
114 (vc-do-command buf 0 "git" name "diff-index" "-p" (or rev1 "HEAD") "--"))
115 ; git-diff-index doesn't set exit status like diff does
116 (if (vc-git-workfile-unchanged-p file) 0 1)))
117
118(defun vc-git-checkin (file rev comment)
119 (let ((coding-system-for-write git-commits-coding-system))
120 (vc-git--run-command file "commit" "-m" comment "--only" "--")))
121
122(defun vc-git-checkout (file &optional editable rev destfile)
123 (if destfile
124 (let ((fullname (substring
125 (vc-git--run-command-string file "ls-files" "-z" "--full-name" "--")
126 0 -1))
127 (coding-system-for-read 'no-conversion)
128 (coding-system-for-write 'no-conversion))
129 (with-temp-file destfile
130 (eq 0 (call-process "git" nil t nil "cat-file" "blob"
131 (concat (or rev "HEAD") ":" fullname)))))
132 (vc-git--run-command file "checkout" (or rev "HEAD"))))
133
134(defun vc-git-annotate-command (file buf &optional rev)
135 ; FIXME: rev is ignored
136 (let ((name (file-relative-name file)))
137 (call-process "git" nil buf nil "blame" name)))
138
139(defun vc-git-annotate-time ()
140 (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)
141 (vc-annotate-convert-time
142 (apply #'encode-time (mapcar (lambda (match) (string-to-number (match-string match))) '(6 5 4 3 2 1 7))))))
143
144;; Not really useful since we can't do anything with the revision yet
145;;(defun vc-annotate-extract-revision-at-line ()
146;; (save-excursion
147;; (move-beginning-of-line 1)
148;; (and (looking-at "[0-9a-f]+")
149;; (buffer-substring (match-beginning 0) (match-end 0)))))
150
151(provide 'vc-git)