Function: package-install-from-archive

package-install-from-archive is a byte-compiled function defined in package.el.gz.

Signature

(package-install-from-archive PKG-DESC)

Documentation

Download and install a package defined by PKG-DESC.

Source Code

;; Defined in /usr/src/emacs/lisp/emacs-lisp/package.el.gz
(defun package-install-from-archive (pkg-desc)
  "Download and install a package defined by PKG-DESC."
  ;; This won't happen, unless the archive is doing something wrong.
  (when (eq (package-desc-kind pkg-desc) 'dir)
    (error "Can't install directory package from archive"))
  (let* ((location (package-archive-base pkg-desc))
         (file (concat (package-desc-full-name pkg-desc)
                       (package-desc-suffix pkg-desc))))
    (package--with-response-buffer location :file file
      (if (or (not (package-check-signature))
              (member (package-desc-archive pkg-desc)
                      package-unsigned-archives))
          ;; If we don't care about the signature, unpack and we're
          ;; done.
          (let ((save-silently t))
            (package-unpack pkg-desc))
        ;; If we care, check it and *then* write the file.
        (let ((content (buffer-string)))
          (package--check-signature
           location file content nil
           ;; This function will be called after signature checking.
           (lambda (&optional good-sigs)
             ;; Signature checked, unpack now.
             (with-temp-buffer ;FIXME: Just use the previous current-buffer.
               (set-buffer-multibyte nil)
               (cl-assert (not (multibyte-string-p content)))
               (insert content)
               (let ((save-silently t))
                 (package-unpack pkg-desc)))
             ;; Here the package has been installed successfully, mark it as
             ;; signed if appropriate.
             (when good-sigs
               ;; Write out good signatures into NAME-VERSION.signed file.
               (write-region (mapconcat #'epg-signature-to-string good-sigs "\n")
                             nil
                             (expand-file-name
                              (concat (package-desc-full-name pkg-desc) ".signed")
                              package-user-dir)
                             nil 'silent)
               ;; Update the old pkg-desc which will be shown on the description buffer.
               (setf (package-desc-signed pkg-desc) t)
               ;; Update the new (activated) pkg-desc as well.
               (when-let* ((pkg-descs (cdr (assq (package-desc-name pkg-desc)
                                                 package-alist))))
                 (setf (package-desc-signed (car pkg-descs)) t))))))))
    ;; fetch a backup of the readme file from the server.  Slot `dir' is
    ;; not yet available in PKG-DESC, so cobble that up.
    (let* ((dirname (package-desc-full-name pkg-desc))
           (pkg-dir (expand-file-name dirname package-user-dir))
           (readme (expand-file-name "README-elpa" pkg-dir)))
      (unless (file-readable-p readme)
        (package--with-response-buffer (package-archive-base pkg-desc)
          :file (format "%s-readme.txt" (package-desc-name pkg-desc))
          :noerror t
          ;; do not write empty or whitespace-only readmes to give
          ;; `package--get-description' a chance to find another readme
          (unless (save-excursion
                    (goto-char (point-min))
                    (looking-at-p "[[:space:]]*\\'"))
            (write-region nil nil readme)))))))