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Diffstat (limited to 'third_party/lisp/mime4cl/streams.lisp')
| -rw-r--r-- | third_party/lisp/mime4cl/streams.lisp | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/third_party/lisp/mime4cl/streams.lisp b/third_party/lisp/mime4cl/streams.lisp new file mode 100644 index 0000000000..dcac6ac341 --- /dev/null +++ b/third_party/lisp/mime4cl/streams.lisp @@ -0,0 +1,355 @@ +;;; streams.lisp --- En/De-coding Streams + +;;; Copyright (C) 2012 by Walter C. Pelissero +;;; Copyright (C) 2021-2022 by the TVL Authors + +;;; Author: Walter C. Pelissero <walter@pelissero.de> +;;; Project: mime4cl + +;;; This library is free software; you can redistribute it and/or +;;; modify it under the terms of the GNU Lesser General Public License +;;; as published by the Free Software Foundation; either version 2.1 +;;; of the License, or (at your option) any later version. +;;; This library 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 +;;; Lesser General Public License for more details. +;;; You should have received a copy of the GNU Lesser General Public +;;; License along with this library; if not, write to the Free +;;; Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA +;;; 02111-1307 USA + +(in-package :mime4cl) + +(defclass coder-stream-mixin () + ((real-stream :type stream + :initarg :stream + :reader real-stream) + (dont-close :initform nil + :initarg :dont-close))) + +(defmethod stream-file-position ((stream coder-stream-mixin)) + (file-position (slot-value stream 'real-stream))) + +(defmethod (setf stream-file-position) (newval (stream coder-stream-mixin)) + (file-position (slot-value stream 'real-stream) newval)) + +(defclass coder-input-stream-mixin (fundamental-binary-input-stream coder-stream-mixin) + ()) +(defclass coder-output-stream-mixin (fundamental-binary-output-stream coder-stream-mixin) + ()) + + +(defclass quoted-printable-decoder-stream (coder-input-stream-mixin quoted-printable-decoder) ()) +(defclass base64-decoder-stream (coder-input-stream-mixin base64-decoder) ()) +(defclass 8bit-decoder-stream (coder-input-stream-mixin 8bit-decoder) ()) + +(defclass quoted-printable-encoder-stream (coder-output-stream-mixin quoted-printable-encoder) ()) +(defclass base64-encoder-stream (coder-output-stream-mixin base64-encoder) ()) +(defclass 8bit-encoder-stream (coder-output-stream-mixin 8bit-encoder) ()) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defmethod initialize-instance :after ((stream coder-stream-mixin) &key &allow-other-keys) + (unless (slot-boundp stream 'real-stream) + (error "REAL-STREAM is unbound. Must provide a :STREAM argument."))) + +(defmethod initialize-instance ((stream coder-output-stream-mixin) &key &allow-other-keys) + (call-next-method) + (unless (slot-boundp stream 'output-function) + (setf (slot-value stream 'output-function) + #'(lambda (char) + (write-char char (slot-value stream 'real-stream)))))) + +(defmethod initialize-instance ((stream coder-input-stream-mixin) &key &allow-other-keys) + (call-next-method) + (unless (slot-boundp stream 'input-function) + (setf (slot-value stream 'input-function) + #'(lambda () + (read-char (slot-value stream 'real-stream) nil))))) + +(defmethod stream-read-byte ((stream coder-input-stream-mixin)) + (or (decoder-read-byte stream) + :eof)) + +(defmethod stream-write-byte ((stream coder-output-stream-mixin) byte) + (encoder-write-byte stream byte)) + +(defmethod close ((stream coder-stream-mixin) &key abort) + (with-slots (real-stream dont-close) stream + (unless dont-close + (close real-stream :abort abort)))) + +(defmethod close ((stream coder-output-stream-mixin) &key abort) + (unless abort + (encoder-finish-output stream)) + (call-next-method)) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defclass encoder-input-stream (fundamental-character-input-stream coder-stream-mixin) + ((encoder) + (buffer-queue :initform (make-queue))) + (:documentation + "This is the base class for encoders with the direction swapped. It +reads from REAL-STREAM a stream of bytes, encodes it and returnes it +in a stream of character.")) + +(defclass quoted-printable-encoder-input-stream (encoder-input-stream) ()) +(defclass base64-encoder-input-stream (encoder-input-stream) ()) +(defclass 8bit-encoder-input-stream (fundamental-character-input-stream coder-stream-mixin) ()) + +(defmethod initialize-instance ((stream quoted-printable-encoder-input-stream) &key &allow-other-keys) + (call-next-method) + (with-slots (encoder buffer-queue) stream + (setf encoder + (make-instance 'quoted-printable-encoder + :output-function #'(lambda (char) + (queue-append buffer-queue char)))))) + +(defmethod initialize-instance ((stream base64-encoder-input-stream) &key &allow-other-keys) + (call-next-method) + (with-slots (encoder buffer-queue) stream + (setf encoder + (make-instance 'base64-encoder + :output-function #'(lambda (char) + (queue-append buffer-queue char)))))) + +(defmethod stream-read-char ((stream encoder-input-stream)) + (with-slots (encoder buffer-queue real-stream) stream + (loop + while (queue-empty-p buffer-queue) + do (be byte (read-byte real-stream nil) + (if byte + (encoder-write-byte encoder byte) + (progn + (encoder-finish-output encoder) + (queue-append buffer-queue :eof))))) + (queue-pop buffer-queue))) + + +(defmethod stream-read-char ((stream 8bit-encoder-input-stream)) + (with-slots (real-stream) stream + (aif (read-byte real-stream nil) + (code-char it) + :eof))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defclass input-adapter-stream () + ((source :initarg :source) + (real-stream) + (input-function))) + +(defclass binary-input-adapter-stream (fundamental-binary-input-stream input-adapter-stream) ()) + +(defclass character-input-adapter-stream (fundamental-character-input-stream input-adapter-stream) ()) + +(defmethod stream-element-type ((stream binary-input-adapter-stream)) + '(unsigned-byte 8)) + +(defmethod initialize-instance ((stream input-adapter-stream) &key &allow-other-keys) + (call-next-method) + (assert (slot-boundp stream 'source))) + +(defmethod initialize-instance ((stream binary-input-adapter-stream) &key &allow-other-keys) + (call-next-method) + ;; REAL-STREAM slot is set only if we are going to close it later on + (with-slots (source real-stream input-function) stream + (etypecase source + (string + (setf real-stream (make-string-input-stream source) + input-function #'(lambda () + (awhen (read-char real-stream nil) + (char-code it))))) + ((vector (unsigned-byte 8)) + (be i 0 + (setf input-function #'(lambda () + (when (< i (length source)) + (prog1 (aref source i) + (incf i))))))) + (stream + (assert (input-stream-p source)) + (setf input-function (if (subtypep (stream-element-type source) 'character) + #'(lambda () + (awhen (read-char source nil) + (char-code it))) + #'(lambda () + (read-byte source nil))))) + (pathname + (setf real-stream (open source :element-type '(unsigned-byte 8)) + input-function #'(lambda () + (read-byte real-stream nil)))) + (file-portion + (setf real-stream (open-decoded-file-portion source) + input-function #'(lambda () + (read-byte real-stream nil))))))) + +(defmethod initialize-instance ((stream character-input-adapter-stream) &key &allow-other-keys) + (call-next-method) + ;; REAL-STREAM slot is set only if we are going to close later on + (with-slots (source real-stream input-function) stream + (etypecase source + (string + (setf real-stream (make-string-input-stream source) + input-function #'(lambda () + (read-char real-stream nil)))) + ((vector (unsigned-byte 8)) + (be i 0 + (setf input-function #'(lambda () + (when (< i (length source)) + (prog1 (code-char (aref source i)) + (incf i))))))) + (stream + (assert (input-stream-p source)) + (setf input-function (if (subtypep (stream-element-type source) 'character) + #'(lambda () + (read-char source nil)) + #'(lambda () + (awhen (read-byte source nil) + (code-char it)))))) + (pathname + (setf real-stream (open source :element-type 'character) + input-function #'(lambda () + (read-char real-stream nil)))) + (file-portion + (setf real-stream (open-decoded-file-portion source) + input-function #'(lambda () + (awhen (read-byte real-stream nil) + (code-char it)))))))) + +(defmethod close ((stream input-adapter-stream) &key abort) + (when (slot-boundp stream 'real-stream) + (with-slots (real-stream) stream + (close real-stream :abort abort)))) + +(defmethod stream-read-byte ((stream binary-input-adapter-stream)) + (with-slots (input-function) stream + (or (funcall input-function) + :eof))) + +(defmethod stream-read-char ((stream character-input-adapter-stream)) + (with-slots (input-function) stream + (or (funcall input-function) + :eof))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defclass delimited-input-stream (fundamental-character-input-stream coder-stream-mixin) + ((start-offset :initarg :start + :initform 0 + :reader stream-start + :type integer) + (end-offset :initarg :end + :initform nil + :reader stream-end + :type (or null integer)) + (current-offset :type integer))) + +(defmethod print-object ((object delimited-input-stream) stream) + (if *print-readably* + (call-next-method) + (with-slots (start-offset end-offset) object + (print-unreadable-object (object stream :type t :identity t) + (format stream "start=~A end=~A" start-offset end-offset))))) + +(defun base-stream (stream) + (if (typep stream 'delimited-input-stream) + (base-stream (real-stream stream)) + stream)) + +(defmethod initialize-instance ((stream delimited-input-stream) &key &allow-other-keys) + (call-next-method) + (unless (slot-boundp stream 'real-stream) + (error "REAL-STREAM is unbound. Must provide a :STREAM argument.")) + (with-slots (start-offset) stream + (file-position stream start-offset))) + +(defmethod (setf stream-file-position) (newval (stream delimited-input-stream)) + (with-slots (current-offset real-stream) stream + (setf current-offset newval) + (call-next-method))) + +(defmethod stream-file-position ((stream delimited-input-stream)) + (slot-value stream 'current-offset)) + +;; Calling file-position with SBCL on every read is quite expensive, since +;; it will invoke lseek each time. This is so expensive that it's faster to +;; /compute/ the amount the stream got advanced by. +;; file-position's behavior however, is quite flexible and it behaves differently +;; not only for different implementation, but also different streams in SBCL. +;; Thus, we should ideally go back to file-position and try to reduce the amount +;; of calls by using read-sequence. +;; TODO(sterni): make decoders use read-sequence and drop offset tracking code +(macrolet ((def-stream-read (name read-fun update-offset-form) + `(defmethod ,name ((stream delimited-input-stream)) + (with-slots (real-stream end-offset current-offset) stream + (let ((el (if (or (not end-offset) + (< current-offset end-offset)) + (or (,read-fun real-stream nil) + :eof) + :eof))) + (setf current-offset ,update-offset-form) + el))))) + + ;; Assume we are using an encoding where < 128 is one byte, in all other cases + ;; it's hard to guess how much file-position will increase + (def-stream-read stream-read-char read-char + (if (or (eq el :eof) (< (char-code el) 128)) + (1+ current-offset) + (file-position real-stream))) + + (def-stream-read stream-read-byte read-byte (1+ current-offset))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defclass my-string-input-stream (fundamental-character-input-stream coder-stream-mixin) + ((string :initarg :string + :reader stream-string))) + +(defmethod initialize-instance ((stream my-string-input-stream) &key &allow-other-keys) + (call-next-method) + (assert (slot-boundp stream 'string)) + (with-slots (string real-stream) stream + (setf real-stream (make-string-input-stream string)))) + +(defmethod stream-read-char ((stream my-string-input-stream)) + (with-slots (real-stream) stream + (or (read-char real-stream nil) + :eof))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defstruct file-portion + data ; string or a pathname + encoding + start + end) + +(defun open-file-portion (file-portion) + (be data (file-portion-data file-portion) + (etypecase data + (pathname + (be stream (open data) + (make-instance 'delimited-input-stream + :stream stream + :start (file-portion-start file-portion) + :end (file-portion-end file-portion)))) + (string + (make-instance 'delimited-input-stream + :stream (make-string-input-stream data) + :start (file-portion-start file-portion) + :end (file-portion-end file-portion))) + (stream + (make-instance 'delimited-input-stream + :stream data + :dont-close t + :start (file-portion-start file-portion) + :end (file-portion-end file-portion)))))) + +(defun open-decoded-file-portion (file-portion) + (make-instance (case (file-portion-encoding file-portion) + (:quoted-printable 'quoted-printable-decoder-stream) + (:base64 'base64-decoder-stream) + (t '8bit-decoder-stream)) + :stream (open-file-portion file-portion))) |