[elpa] elpa-admin a7a8990 132/357: Fix prefix of last merge and restore deleted files

[Stefan Monnier]

branch: elpa-admin
commit a7a8990c27c85c32cb5112b498bea1aba71e7fba
Author: Leo Liu <sdl.web@gmail.com>
Commit: Leo Liu <sdl.web@gmail.com>

    Fix prefix of last merge and restore deleted files
    
    See discussion
    http://lists.gnu.org/archive/html/emacs-devel/2014-04/msg00311.html
---
 admin/archive-contents.el | 588 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 588 insertions(+)

diff --git a/admin/archive-contents.el b/admin/archive-contents.el
new file mode 100644
index 0000000..241f1ad
--- /dev/null
+++ b/admin/archive-contents.el
@@ -0,0 +1,588 @@
+;;; archive-contents.el --- Auto-generate an Emacs Lisp package archive.  -*- 
lexical-binding:t -*-
+
+;; Copyright (C) 2011-2014  Free Software Foundation, Inc
+
+;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(eval-when-compile (require 'cl))
+(require 'lisp-mnt)
+(require 'package)
+(require 'pcase)
+
+(defconst archive-contents-subdirectory-regexp
+  
"\\([^.].*?\\)-\\([0-9]+\\(?:[.][0-9]+\\|\\(?:pre\\|beta\\|alpha\\)[0-9]+\\)*\\)")
+
+(defconst archive-re-no-dot "\\`\\([^.]\\|\\.\\([^.]\\|\\..\\)\\).*"
+  "Regular expression matching all files except \".\" and \"..\".")
+
+(defun archive--version-to-list (vers)
+  (when vers
+    (let ((l (version-to-list vers)))
+      ;; Signal an error for things like "1.02" which is parsed as "1.2".
+      (assert (equal vers (package-version-join l)) nil
+              "Unsupported version syntax %S" vers)
+      l)))
+
+(defun archive--convert-require (elt)
+  (list (car elt)
+       (archive--version-to-list (car (cdr elt)))))
+
+(defun archive--strip-rcs-id (str)
+  "Strip RCS version ID from the version string STR.
+If the result looks like a dotted numeric version, return it.
+Otherwise return nil."
+  (when str
+    (when (string-match "\\`[ \t]*[$]Revision:[ \t]+" str)
+      (setq str (substring str (match-end 0))))
+    (condition-case nil
+        (if (archive--version-to-list str)
+            str)
+      (error str))))
+
+(defun archive--delete-elc-files (dir &optional only-orphans)
+  "Recursively delete all .elc files in DIR.
+Delete backup files also."
+  (dolist (f (directory-files dir t archive-re-no-dot))
+    (cond ((file-directory-p f)
+          (archive--delete-elc-files f))
+         ((or (and (string-match "\\.elc\\'" f)
+                    (not (and only-orphans
+                              (file-readable-p (replace-match ".el" t t f)))))
+              (backup-file-name-p f))
+          (delete-file f)))))
+
+(defun batch-make-archive ()
+  "Process package content directories and generate the archive-contents file."
+  (let ((packages '(1))) ; format-version.
+    (dolist (dir (directory-files default-directory nil archive-re-no-dot))
+      (condition-case v
+         (if (not (file-directory-p dir))
+             (message "Skipping non-package file %s" dir)
+           (let* ((pkg (file-name-nondirectory dir))
+                  (autoloads-file (expand-file-name (concat pkg 
"-autoloads.el") dir)))
+             ;; Omit autoloads and .elc files from the package.
+             (if (file-exists-p autoloads-file)
+                 (delete-file autoloads-file))
+             (archive--delete-elc-files dir)
+             (let ((metadata (archive--metadata dir pkg)))
+                ;; (nth 1 metadata) is nil for "org" which is the only package
+                ;; still using the "org-pkg.el file to specify the metadata.
+                (if (and (nth 1 metadata)
+                         (< (string-to-number (nth 1 metadata)) 0))
+                    (progn ;; Negative version: don't publish this package yet!
+                      (message "Package %s not released yet!" dir)
+                      (delete-directory dir 'recursive))
+                  (push (if (car metadata)
+                            (apply #'archive--process-simple-package
+                                   dir pkg (cdr metadata))
+                          (if (nth 1 metadata)
+                              (apply #'archive--write-pkg-file
+                                     dir pkg (cdr metadata)))
+                          (archive--process-multi-file-package dir pkg))
+                        packages)))))
+       ((debug error) (error "Error in %s: %S" dir v))))
+    (with-temp-buffer
+      (pp (nreverse packages) (current-buffer))
+      (write-region nil nil "archive-contents"))))
+
+(defconst archive--revno-re "[0-9a-f]+")
+
+(defun archive-prepare-packages (srcdir)
+  "Prepare the `packages' directory inside the Git checkout.
+Expects to be called from within the `packages' directory.
+\"Prepare\" here is for subsequent construction of the packages and archive,
+so it is meant to refresh any generated files we may need.
+Currently only refreshes the ChangeLog files."
+  (setq srcdir (file-name-as-directory (expand-file-name srcdir)))
+  (let* ((wit ".changelog-witness")
+         (prevno (with-temp-buffer
+                   (insert-file-contents wit)
+                   (if (looking-at (concat archive--revno-re "$"))
+                       (match-string 0)
+                     (error "Can't find previous revision name"))))
+         (new-revno
+          (or (with-temp-buffer
+                (let ((default-directory srcdir))
+                  (call-process "git" nil '(t) nil "rev-parse" "HEAD")
+                  (goto-char (point-min))
+                  (when (looking-at (concat archive--revno-re "$"))
+                    (match-string 0))))
+              (error "Couldn't find the current revision's name")))
+         (pkgs '()))
+    (unless (equal prevno new-revno)
+      (with-temp-buffer
+        (let ((default-directory srcdir))
+          (unless (zerop (call-process "git" nil '(t) nil "diff"
+                                       "--dirstat=cumulative,0"
+                                       prevno))
+            (error "Error signaled by git diff --dirstat %d" prevno)))
+        (goto-char (point-min))
+        (while (re-search-forward "^[ \t.0-9%]* packages/\\([-[:alnum:]]+\\)/$"
+                                  nil t)
+          (push (match-string 1) pkgs))))
+    (let ((default-directory (expand-file-name "packages/")))
+      (dolist (pkg pkgs)
+        (condition-case v
+            (if (file-directory-p pkg)
+                (archive--make-changelog pkg (expand-file-name "packages/"
+                                                               srcdir)))
+          (error (message "Error: %S" v)))))
+    (write-region new-revno nil wit nil 'quiet)
+    ;; Also update the ChangeLog of external packages.
+    (let ((default-directory (expand-file-name "packages/")))
+      (dolist (dir (directory-files "."))
+        (and (not (member dir '("." "..")))
+             (file-directory-p dir)
+             (let ((index (expand-file-name
+                           (concat "packages/" dir "/.git/index")
+                           srcdir))
+                   (cl (expand-file-name "ChangeLog" dir)))
+               (and (file-exists-p index)
+                    (or (not (file-exists-p cl))
+                        (file-newer-than-file-p index cl))))
+             (archive--make-changelog
+              dir (expand-file-name "packages/" srcdir)))))
+    ))
+
+(defun archive--metadata (dir pkg)
+  "Return a list (SIMPLE VERSION DESCRIPTION REQ EXTRAS),
+where SIMPLE is non-nil if the package is simple;
+VERSION is the version string of the simple package;
+DESCRIPTION is the brief description of the package;
+REQ is a list of requirements;
+EXTRAS is an alist with additional metadata.
+
+PKG is the name of the package and DIR is the directory where it is."
+  (let* ((mainfile (expand-file-name (concat pkg ".el") dir))
+         (files (directory-files dir nil "\\.el\\'")))
+    (setq files (delete (concat pkg "-pkg.el") files))
+    (setq files (delete (concat pkg "-autoloads.el") files))
+    (cond
+     ((file-exists-p mainfile)
+      (with-temp-buffer
+       (insert-file-contents mainfile)
+       (goto-char (point-min))
+       (if (not (looking-at ";;;.*---[ \t]*\\(.*?\\)[ \t]*\\(-\\*-.*-\\*-[ 
\t]*\\)?$"))
+            (error "Can't parse first line of %s" mainfile)
+          ;; Grab the other fields, which are not mandatory.
+          (let* ((description (match-string 1))
+                 (version
+                  (or (archive--strip-rcs-id (lm-header "package-version"))
+                      (archive--strip-rcs-id (lm-header "version"))
+                      (unless (equal pkg "org")
+                        (error "Missing `version' header"))))
+                 (requires-str (lm-header "package-requires"))
+                 (pt (lm-header "package-type"))
+                 (simple (if pt (equal pt "simple") (= (length files) 1)))
+                 (keywords (lm-keywords-list))
+                 (url (or (lm-header "url")
+                          (format "http://elpa.gnu.org/packages/%s.html"; pkg)))
+                 (req
+                  (if requires-str
+                      (mapcar 'archive--convert-require
+                              (car (read-from-string requires-str))))))
+            (list simple version description req
+                  ;; extra parameters
+                  (list (cons :url url)
+                        (cons :keywords keywords)))))))
+     (t
+      (error "Can find main file %s file in %s" mainfile dir)))))
+
+(defun archive--process-simple-package (dir pkg vers desc req extras)
+  "Deploy the contents of DIR into the archive as a simple package.
+Rename DIR/PKG.el to PKG-VERS.el, delete DIR, and return the descriptor."
+  ;; Write DIR/foo.el to foo-VERS.el and delete DIR
+  (rename-file (expand-file-name (concat pkg ".el") dir)
+              (concat pkg "-" vers ".el"))
+  ;; Add the content of the ChangeLog.
+  (let ((cl (expand-file-name "ChangeLog" dir)))
+    (with-current-buffer (find-file-noselect (concat pkg "-" vers ".el"))
+      (goto-char (point-max))
+      (re-search-backward "^;;;.*ends here")
+      (re-search-backward "^(provide")
+      (skip-chars-backward " \t\n")
+      (insert "\n\n;;;; ChangeLog:\n\n")
+      (let* ((start (point))
+             (end (copy-marker start t)))
+        (condition-case nil
+            (insert-file-contents cl)
+          (file-error (message "Can't find %S's ChangeLog file" pkg)))
+        (goto-char end)
+        (unless (bolp) (insert "\n"))
+        (while (progn (forward-line -1) (>= (point) start))
+          (insert ";; ")))
+      (set (make-local-variable 'backup-inhibited) t)
+      (basic-save-buffer)               ;Less chatty than save-buffer.
+      (kill-buffer)))
+  (delete-directory dir t)
+  (cons (intern pkg) (vector (archive--version-to-list vers)
+                             req desc 'single extras)))
+
+(defun archive--make-changelog (dir srcdir)
+  "Export Git log info of DIR into a ChangeLog file."
+  (message "Refreshing ChangeLog in %S" dir)
+  (let ((default-directory (file-name-as-directory (expand-file-name dir))))
+    (with-temp-buffer
+      (set-buffer-multibyte nil)
+      (let ((coding-system-for-read 'binary)
+            (coding-system-for-write 'binary))
+        (if (file-readable-p "ChangeLog") (insert-file-contents "ChangeLog"))
+        (let ((old-md5 (md5 (current-buffer))))
+          (erase-buffer)
+          (let ((default-directory
+                  (file-name-as-directory (expand-file-name dir srcdir))))
+            (call-process "git" nil (current-buffer) nil
+                          "log" "--date=short"
+                          "--format=%cd  %aN  <%ae>%n%n%w(80,8,8)%B%n"
+                          "."))
+          (tabify (point-min) (point-max))
+          (goto-char (point-min))
+          (while (re-search-forward "\n\n\n+" nil t)
+            (replace-match "\n\n"))
+          (if (equal old-md5 (md5 (current-buffer)))
+              (message "ChangeLog's md5 unchanged for %S" dir)
+            (write-region (point-min) (point-max) "ChangeLog" nil 'quiet)))))))
+
+(defun archive--alist-to-plist-args (alist)
+  (mapcar (lambda (x)
+            (if (and (not (consp x))
+                     (or (keywordp x)
+                         (not (symbolp x))
+                         (memq x '(nil t))))
+                x `',x))
+          (apply #'nconc
+                 (mapcar (lambda (pair) (list (car pair) (cdr pair))) alist))))
+
+(defun archive--plist-args-to-alist (plist)
+  (let (alist)
+    (while plist
+      (let ((value (cadr plist)))
+        (when value
+          (cl-assert (keywordp (car plist)))
+          (push (cons (car plist)
+                      (if (eq 'quote (car-safe value)) (cadr value) value))
+                alist)))
+      (setq plist (cddr plist)))
+    alist))
+
+(defun archive--process-multi-file-package (dir pkg)
+  "Deploy the contents of DIR into the archive as a multi-file package.
+Rename DIR/ to PKG-VERS/, and return the descriptor."
+  (let* ((exp (archive--multi-file-package-def dir pkg))
+        (vers (nth 2 exp))
+         (req-exp (nth 4 exp))
+        (req (mapcar 'archive--convert-require
+                      (if (eq 'quote (car-safe req-exp)) (nth 1 req-exp)
+                        (when req-exp
+                          (error "REQ should be a quoted constant: %S"
+                                 req-exp)))))
+         (extras (archive--plist-args-to-alist (nthcdr 5 exp))))
+    (unless (equal (nth 1 exp) pkg)
+      (error (format "Package name %s doesn't match file name %s"
+                    (nth 1 exp) pkg)))
+    (rename-file dir (concat pkg "-" vers))
+    (cons (intern pkg) (vector (archive--version-to-list vers)
+                               req (nth 3 exp) 'tar extras))))
+
+(defun archive--multi-file-package-def (dir pkg)
+  "Return the `define-package' form in the file DIR/PKG-pkg.el."
+  (let ((pkg-file (expand-file-name (concat pkg "-pkg.el") dir)))
+    (with-temp-buffer
+      (unless (file-exists-p pkg-file)
+       (error "File not found: %s" pkg-file))
+      (insert-file-contents pkg-file)
+      (goto-char (point-min))
+      (read (current-buffer)))))
+
+(defun archive--refresh-pkg-file ()
+  (let* ((dir (directory-file-name default-directory))
+         (pkg (file-name-nondirectory dir)))
+    (apply #'archive--write-pkg-file dir pkg
+           (cdr (archive--metadata dir pkg)))))
+
+(defun archive--write-pkg-file (pkg-dir name version desc requires extras)
+  (let ((pkg-file (expand-file-name (concat name "-pkg.el") pkg-dir))
+       (print-level nil)
+        (print-quoted t)
+       (print-length nil))
+    (write-region
+     (concat (format ";; Generated package description from %s.el\n"
+                    name)
+            (prin1-to-string
+              (nconc
+               (list 'define-package
+                     name
+                     version
+                     desc
+                     (list 'quote
+                           ;; Turn version lists into string form.
+                           (mapcar
+                            (lambda (elt)
+                              (list (car elt)
+                                    (package-version-join (cadr elt))))
+                            requires)))
+               (archive--alist-to-plist-args extras)))
+            "\n")
+     nil
+     pkg-file)))
+
+;;; Make the HTML pages for online browsing.
+
+(defun archive--html-header (title)
+  (format "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 3.2 Final//EN\">
+<html>
+<head>
+  <title>%s</title>
+  <meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\">
+</head>
+<body>
+<h1 align=\"center\">%s</h1>\n"
+          title title))
+
+(defun archive--html-bytes-format (bytes) ;Aka memory-usage-format.
+  (setq bytes (/ bytes 1024.0))
+  (let ((units '(;; "B"
+                 "kB" "MB" "GB" "TB")))
+    (while (>= bytes 1024)
+      (setq bytes (/ bytes 1024.0))
+      (setq units (cdr units)))
+    (cond
+     ;; ((integerp bytes) (format "%4d%s" bytes (car units)))
+     ((>= bytes 100) (format "%4.0f%s" bytes (car units)))
+     ((>= bytes 10) (format "%4.1f%s" bytes (car units)))
+     (t (format "%4.2f%s" bytes (car units))))))
+
+(defun archive--get-prop (prop name srcdir mainsrcfile)
+  (let ((kprop (intern (format ":%s" (downcase prop)))))
+    (or
+     (let ((pkgdescfile (expand-file-name (format "%s-pkg.el" name)
+                                          srcdir)))
+       (when (file-readable-p pkgdescfile)
+         (with-temp-buffer
+           (insert-file-contents pkgdescfile)
+           (let ((desc (read (current-buffer))))
+             (plist-get (cdr desc) kprop)))))
+     (when (file-readable-p mainsrcfile)
+       (with-temp-buffer
+         (insert-file-contents mainsrcfile)
+         (lm-header prop))))))
+
+(defun archive--get-section (hsection fsection srcdir mainsrcfile)
+  (when (consp fsection)
+    (while (cdr-safe fsection)
+      (setq fsection
+            (if (file-readable-p (expand-file-name (car fsection) srcdir))
+                (car fsection)
+              (cdr fsection))))
+    (when (consp fsection) (setq fsection (car fsection))))
+  (cond
+   ((file-readable-p (expand-file-name fsection srcdir))
+    (with-temp-buffer
+      (insert-file-contents (expand-file-name fsection srcdir))
+      (buffer-string)))
+   ((file-readable-p mainsrcfile)
+    (with-temp-buffer
+      (insert-file-contents mainsrcfile)
+      (let ((start (lm-section-start hsection)))
+        (when start
+          (insert
+           (prog1
+               (buffer-substring start (lm-section-end hsection))
+             (erase-buffer)))
+          (emacs-lisp-mode)
+          (goto-char (point-min))
+          (delete-region (point) (line-beginning-position 2))
+          (uncomment-region (point-min) (point-max))
+          (when (looking-at "^\\([ \t]*\n\\)+")
+            (replace-match ""))
+          (goto-char (point-max))
+          (skip-chars-backward " \t\n")
+          (delete-region (point) (point-max))
+          (buffer-string)))))))
+
+(defun archive--quote (txt)
+  (replace-regexp-in-string "<" "&lt;"
+                            (replace-regexp-in-string "&" "&amp;" txt)))
+
+(defun archive--insert-repolinks (name srcdir mainsrcfile url)
+  (if url
+      (insert (format "<p>Origin: <a href=%S>%s</a></p>\n"
+                      url (archive--quote url)))
+    (let* ((externals
+            (with-temp-buffer
+              (insert-file-contents
+               (expand-file-name "../../../elpa/externals-list" srcdir))
+              (read (current-buffer))))
+           (external (eq :external (nth 1 (assoc name externals))))
+           (git-sv "http://git.savannah.gnu.org/";)
+           (urls (if external
+                     '("cgit/emacs/elpa.git/?h=externals/"
+                       
"gitweb/?p=emacs/elpa.git;a=shortlog;h=refs/heads/externals/")
+                   '("cgit/emacs/elpa.git/tree/packages/"
+                     "gitweb/?p=emacs/elpa.git;a=tree;f=packages/"))))
+      (insert (format
+               (concat "<p>Browse repository: <a href=%S>%s</a>"
+                       " or <a href=%S>%s</a></p>\n")
+               (concat git-sv (nth 0 urls) name)
+               'CGit
+               (concat git-sv (nth 1 urls) name)
+               'Gitweb)))))
+
+(defun archive--html-make-pkg (pkg files)
+  (let* ((name (symbol-name (car pkg)))
+         (latest (package-version-join (aref (cdr pkg) 0)))
+         (srcdir (expand-file-name name "../../build/packages"))
+         (mainsrcfile (expand-file-name (format "%s.el" name) srcdir))
+         (desc (aref (cdr pkg) 2)))
+    (with-temp-buffer
+      (insert (archive--html-header (format "GNU ELPA - %s" name)))
+      (insert (format "<p>Description: %s</p>\n" (archive--quote desc)))
+      (let* ((file (cdr (assoc latest files)))
+             (attrs (file-attributes file)))
+        (insert (format "<p>Latest: <a href=%S>%s</a>, %s, %s</p>\n"
+                        file (archive--quote file)
+                        (format-time-string "%Y-%b-%d" (nth 5 attrs))
+                        (archive--html-bytes-format (nth 7 attrs)))))
+      (let ((maint (archive--get-prop "Maintainer" name srcdir mainsrcfile)))
+        (when maint
+          (insert (format "<p>Maintainer: %s</p>\n" (archive--quote maint)))))
+      (archive--insert-repolinks name srcdir mainsrcfile
+                                 (cdr (assoc :url (aref (cdr pkg) 4))))
+      (let ((rm (archive--get-section
+                 "Commentary" '("README" "README.rst"
+                                ;; Most README.md files seem to be currently
+                                ;; worse than the Commentary: section :-(
+                                ;; "README.md"
+                                "README.org")
+                 srcdir mainsrcfile)))
+        (when rm
+          (write-region rm nil (concat name "-readme.txt"))
+          (insert "<h2>Full description</h2><pre>\n" (archive--quote rm)
+                  "\n</pre>\n")))
+      (unless (< (length files) 2)
+        (insert (format "<h2>Old versions</h2><table cellpadding=\"3\" 
border=\"1\">\n"))
+        (dolist (file files)
+          (unless (equal (pop file) latest)
+            (let ((attrs (file-attributes file)))
+              (insert (format "<tr><td><a 
href=%S>%s</a></td><td>%s</td><td>%s</td>\n"
+                              file (archive--quote file)
+                              (format-time-string "%Y-%b-%d" (nth 5 attrs))
+                              (archive--html-bytes-format (nth 7 attrs)))))))
+        (insert "</table>\n"))
+      (let ((news (archive--get-section
+                   "News" '("NEWS" "NEWS.rst" "NEWS.md" "NEWS.org")
+                   srcdir mainsrcfile)))
+        (when news
+          (insert "<h2>News</h2><pre>\n" (archive--quote news) "\n</pre>\n")))
+      (insert "</body>\n")
+      (write-region (point-min) (point-max) (concat name ".html")))))
+
+(defun archive--html-make-index (pkgs)
+  (with-temp-buffer
+    (insert (archive--html-header "GNU ELPA Packages"))
+    (insert "<table cellpadding=\"3\" border=\"1\">\n")
+    (insert "<tr><th>Package</th><th>Version</th><th>Description</th></tr>\n")
+    (dolist (pkg pkgs)
+      (insert (format "<tr><td><a 
href=\"%s.html\">%s</a></td><td>%s</td><td>%s</td></tr>\n"
+                      (car pkg) (car pkg)
+                      (package-version-join (aref (cdr pkg) 0))
+                      (aref (cdr pkg) 2))))
+    (insert "</table></body>\n")
+    (write-region (point-min) (point-max) "index.html")))
+
+(defun batch-html-make-index ()
+  (let ((packages (make-hash-table :test #'equal))
+        (archive-contents
+         (with-temp-buffer
+           (insert-file-contents "archive-contents")
+           (goto-char (point-min))
+           ;; Skip the first element which is a version number.
+           (cdr (read (current-buffer))))))
+    (dolist (file (directory-files default-directory nil))
+      (cond
+       ((member file '("." ".." "elpa.rss" "index.html" "archive-contents")))
+       ((string-match "\\.html\\'" file))
+       ((string-match "-readme\\.txt\\'" file)
+        (let ((name (substring file 0 (match-beginning 0))))
+          (puthash name (gethash name packages) packages)))
+       ((string-match "-\\([0-9][^-]*\\)\\.\\(tar\\|el\\)\\'" file)
+        (let ((name (substring file 0 (match-beginning 0)))
+              (version (match-string 1 file)))
+          (push (cons version file) (gethash name packages))))
+       (t (message "Unknown file %S" file))))
+    (dolist (pkg archive-contents)
+      (archive--html-make-pkg pkg (gethash (symbol-name (car pkg)) packages)))
+    ;; FIXME: Add (old?) packages that are in `packages' but not in
+    ;; archive-contents.
+    (archive--html-make-index archive-contents)))
+
+;;; Maintain external packages.
+
+(defconst archive--elpa-git-url "git://git.sv.gnu.org/emacs/elpa")
+
+(defun archive-add/remove/update-externals ()
+  (let ((exts (with-current-buffer (find-file-noselect "externals-list")
+                (goto-char (point-min))
+                (read (current-buffer)))))
+    (let ((default-directory (expand-file-name "packages/")))
+      ;; Remove "old/odd" externals.
+      (dolist (dir (directory-files "."))
+        (cond
+         ((member dir '("." "..")) nil)
+         ((assoc dir exts) nil)
+         ((file-directory-p (expand-file-name (format "%s/.git" dir)))
+          (let ((status
+                 (with-temp-buffer
+                   (let ((default-directory (file-name-as-directory
+                                             (expand-file-name dir))))
+                     (call-process "git" nil t nil "status" "--porcelain")
+                     (buffer-string)))))
+            (if (zerop (length status))
+                (progn (delete-directory dir 'recursive t)
+                       (message "Deleted all of %s" dir))
+              (message "Keeping leftover unclean %s:\n%s" dir status))))))
+      (pcase-dolist (`(,dir ,kind ,_url) exts)
+        (cond
+         ((eq kind :subtree) nil)       ;Nothing to do.
+         ((not (eq kind :external))
+          (message "Unknown external package kind `%S' for %s" kind dir))
+         ((not (file-exists-p dir))
+          (let* ((branch (concat "externals/" dir))
+                 (output
+                  (with-temp-buffer
+                    ;; FIXME: Use git-new-workdir!
+                    (call-process "git" nil t nil "clone"
+                                  "--reference" ".." "--branch" branch
+                                  archive--elpa-git-url dir)
+                    (buffer-string))))
+            (message "Cloning branch %s:\n%s" dir output)))
+         ((not (file-directory-p (concat dir "/.git")))
+          (message "%s is in the way of an external, please remove!" dir))
+         (t
+          (let ((default-directory (file-name-as-directory
+                                    (expand-file-name dir))))
+            (with-temp-buffer
+              (message "Running git pull in %S" default-directory)
+              (call-process "git" nil t nil "pull")
+              (message "Updated %s:%s" dir (buffer-string))))
+          ))))))
+
+(provide 'archive-contents)
+;;; archive-contents.el ends here