end))))
\f
;;;; STRING-OUTPUT-STREAM stuff
+;;;;
+;;;; FIXME: This, like almost none of the stream code is particularly
+;;;; interrupt or thread-safe. While it should not be possible to
+;;;; corrupt the heap here, it certainly is possible to end up with
+;;;; a string-output-stream whose internal state is messed up.
+;;;;
+;;;; FIXME: It would be nice to support space-efficient
+;;;; string-output-streams with element-type base-char. This would
+;;;; mean either a separate subclass, or typecases in functions.
+
+(defparameter *string-output-stream-buffer-initial-size* 64)
+#!-sb-fluid
+(declaim (inline string-output-string-stream-buffer
+ string-output-string-stream-pointer
+ string-output-string-stream-index))
(defstruct (string-output-stream
(:include ansi-stream
(out #'string-ouch)
(misc #'string-out-misc))
(:constructor make-string-output-stream
(&key (element-type 'character)
- &aux (string (make-string 40))))
+ &aux (buffer
+ (make-string
+ *string-output-stream-buffer-initial-size*))))
(:copier nil))
;; The string we throw stuff in.
- (string (missing-arg) :type (simple-array character (*)))
- ;; Index of the next location to use.
- (index 0 :type fixnum)
- ;; Index cache for string-output-stream-last-index
- (index-cache 0 :type fixnum)
+ (buffer (missing-arg) :type (simple-array character (*)))
+ ;; Chains of buffers to use
+ (prev nil)
+ (next nil)
+ ;; Index of the next location to use in the current string.
+ (pointer 0 :type index)
+ ;; Global location in the stream
+ (index 0 :type index)
+ ;; Index cache: when we move backwards we save the greater of this
+ ;; and index here, so the the greater of index and this is always
+ ;; the end of the stream.
+ (index-cache 0 :type index)
;; Requested element type
(element-type 'character))
#!+sb-doc
(setf (fdocumentation 'make-string-output-stream 'function)
- "Return an output stream which will accumulate all output given it for
- the benefit of the function GET-OUTPUT-STREAM-STRING.")
-
-(defun string-output-stream-last-index (stream)
- (max (string-output-stream-index stream)
- (string-output-stream-index-cache stream)))
+ "Return an output stream which will accumulate all output given it for the
+benefit of the function GET-OUTPUT-STREAM-STRING.")
+
+;;; Pushes the current segment onto the prev-list, and either pops
+;;; or allocates a new one.
+(defun string-output-stream-new-buffer (stream size)
+ (declare (index size))
+ (/show0 "/string-output-stream-new-buffer")
+ (push (string-output-stream-buffer stream)
+ (string-output-stream-prev stream))
+ (setf (string-output-stream-buffer stream)
+ (or (pop (string-output-stream-next stream))
+ ;; FIXME: This would be the correct place to detect that
+ ;; more then FIXNUM characters are being written to the
+ ;; stream, and do something about it.
+ (make-string size))))
+
+;;; Moves to the end of the next segment or the current one if there are
+;;; no more segments. Returns true as long as there are next segments.
+(defun string-output-stream-next-buffer (stream)
+ (/show0 "/string-output-stream-next-buffer")
+ (let* ((old (string-output-stream-buffer stream))
+ (new (pop (string-output-stream-next stream)))
+ (old-size (length old))
+ (skipped (- old-size (string-output-stream-pointer stream))))
+ (cond (new
+ (let ((new-size (length new)))
+ (push old (string-output-stream-prev stream))
+ (setf (string-output-stream-buffer stream) new
+ (string-output-stream-pointer stream) new-size)
+ (incf (string-output-stream-index stream) (+ skipped new-size)))
+ t)
+ (t
+ (setf (string-output-stream-pointer stream) old-size)
+ (incf (string-output-stream-index stream) skipped)
+ nil))))
+
+;;; Moves to the start of the previous segment or the current one if there
+;;; are no more segments. Returns true as long as there are prev segments.
+(defun string-output-stream-prev-buffer (stream)
+ (/show0 "/string-output-stream-prev-buffer")
+ (let ((old (string-output-stream-buffer stream))
+ (new (pop (string-output-stream-prev stream)))
+ (skipped (string-output-stream-pointer stream)))
+ (cond (new
+ (push old (string-output-stream-next stream))
+ (setf (string-output-stream-buffer stream) new
+ (string-output-stream-pointer stream) 0)
+ (decf (string-output-stream-index stream) (+ skipped (length new)))
+ t)
+ (t
+ (setf (string-output-stream-pointer stream) 0)
+ (decf (string-output-stream-index stream) skipped)
+ nil))))
(defun string-ouch (stream character)
- (let ((current (string-output-stream-index stream))
- (workspace (string-output-stream-string stream)))
- (declare (type (simple-array character (*)) workspace)
- (type fixnum current))
- (if (= current (the fixnum (length workspace)))
- (let ((new-workspace (make-string (* current 2))))
- (replace new-workspace workspace)
- (setf (aref new-workspace current) character
- (string-output-stream-string stream) new-workspace))
- (setf (aref workspace current) character))
- (setf (string-output-stream-index stream) (1+ current))))
+ (/show0 "/string-ouch")
+ (let ((pointer (string-output-stream-pointer stream))
+ (buffer (string-output-stream-buffer stream))
+ (index (string-output-stream-index stream)))
+ (cond ((= pointer (length buffer))
+ (setf buffer (string-output-stream-new-buffer stream index)
+ (aref buffer 0) character
+ (string-output-stream-pointer stream) 1))
+ (t
+ (setf (aref buffer pointer) character
+ (string-output-stream-pointer stream) (1+ pointer))))
+ (setf (string-output-stream-index stream) (1+ index))))
(defun string-sout (stream string start end)
(declare (type simple-string string)
- (type fixnum start end))
- (let* ((string (if (typep string '(simple-array character (*)))
- string
- (coerce string '(simple-array character (*)))))
- (current (string-output-stream-index stream))
- (length (- end start))
- (dst-end (+ length current))
- (workspace (string-output-stream-string stream)))
- (declare (type (simple-array character (*)) workspace string)
- (type fixnum current length dst-end))
- (if (> dst-end (the fixnum (length workspace)))
- (let ((new-workspace (make-string (+ (* current 2) length))))
- (replace new-workspace workspace :end2 current)
- (replace new-workspace string
- :start1 current :end1 dst-end
- :start2 start :end2 end)
- (setf (string-output-stream-string stream) new-workspace))
- (replace workspace string
- :start1 current :end1 dst-end
- :start2 start :end2 end))
- (setf (string-output-stream-index stream) dst-end)))
+ (type index start end))
+ (let* ((full-length (- end start))
+ (length full-length)
+ (buffer (string-output-stream-buffer stream))
+ (pointer (string-output-stream-pointer stream))
+ (space (- (length buffer) pointer))
+ (here (min space length))
+ (stop (+ start here))
+ (overflow (- length space)))
+ (declare (index length space here stop full-length)
+ (fixnum overflow)
+ (type (simple-array character (*)) buffer))
+ (tagbody
+ :more
+ (when (plusp here)
+ (etypecase string
+ ((simple-array character (*))
+ (replace buffer string :start1 pointer :start2 start :end2 stop))
+ (simple-base-string
+ (replace buffer string :start1 pointer :start2 start :end2 stop))
+ ((simple-array nil (*))
+ (replace buffer string :start1 pointer :start2 start :end2 stop)))
+ (setf (string-output-stream-pointer stream) (+ here pointer)))
+ (when (plusp overflow)
+ (setf start stop
+ length (- end start)
+ buffer (string-output-stream-new-buffer
+ stream (max overflow (string-output-stream-index stream)))
+ pointer 0
+ space (length buffer)
+ here (min space length)
+ stop (+ start here)
+ ;; there may be more overflow if we used a buffer
+ ;; already allocated to the stream
+ overflow (- length space))
+ (go :more)))
+ (incf (string-output-stream-index stream) full-length)))
+
+;;; Factored out of the -misc method due to size.
+(defun set-string-output-stream-file-position (stream pos)
+ (let* ((index (string-output-stream-index stream))
+ (end (max index (string-output-stream-index-cache stream))))
+ (declare (index index end))
+ (setf (string-output-stream-index-cache stream) end)
+ (cond ((eq :start pos)
+ (loop while (string-output-stream-prev-buffer stream)))
+ ((eq :end pos)
+ (loop while (string-output-stream-next-buffer stream))
+ (let ((over (- (string-output-stream-index stream) end)))
+ (decf (string-output-stream-pointer stream) over))
+ (setf (string-output-stream-index stream) end))
+ ((< pos index)
+ (loop while (< pos index)
+ do (string-output-stream-prev-buffer stream)
+ (setf index (string-output-stream-index stream)))
+ (let ((step (- pos index)))
+ (incf (string-output-stream-pointer stream) step)
+ (setf (string-output-stream-index stream) pos)))
+ ((> pos index)
+ ;; We allow moving beyond the end of stream, implicitly
+ ;; extending the output stream.
+ (let ((next (string-output-stream-next-buffer stream)))
+ ;; Update after -next-buffer, INDEX is kept pointing at
+ ;; the end of the current buffer.
+ (setf index (string-output-stream-index stream))
+ (loop while (and next (> pos index))
+ do (setf next (string-output-stream-next-buffer stream)
+ index (string-output-stream-index stream))))
+ ;; Allocate new buffer if needed, or step back to
+ ;; the desired index and set pointer and index
+ ;; correctly.
+ (let ((diff (- pos index)))
+ (if (plusp diff)
+ (let* ((new (string-output-stream-new-buffer stream diff))
+ (size (length new)))
+ (aver (= pos (+ index size)))
+ (setf (string-output-stream-pointer stream) size
+ (string-output-stream-index stream) pos))
+ (let ((size (length (string-output-stream-buffer stream))))
+ (setf (string-output-stream-pointer stream) (+ size diff)
+ (string-output-stream-index stream) pos))))))))
(defun string-out-misc (stream operation &optional arg1 arg2)
(declare (ignore arg2))
(case operation
- (:file-position
- (if arg1
- (let ((end (string-output-stream-last-index stream)))
- (setf (string-output-stream-index-cache stream) end
- (string-output-stream-index stream)
- (case arg1
- (:start 0)
- (:end end)
- (t
- ;; We allow moving beyond the end of stream,
- ;; implicitly extending the output stream.
- (let ((buffer (string-output-stream-string stream)))
- (when (> arg1 (length buffer))
- (setf (string-output-stream-string stream)
- (make-string
- arg1 :element-type (array-element-type buffer))
- (subseq (string-output-stream-string stream)
- 0 end)
- (subseq buffer 0 end))))
- arg1))))
- (string-output-stream-index stream)))
- (:close (set-closed-flame stream))
(:charpos
- (do ((index (1- (the fixnum (string-output-stream-index stream)))
- (1- index))
- (count 0 (1+ count))
- (string (string-output-stream-string stream)))
- ((< index 0) count)
- (declare (type (simple-array character (*)) string)
- (type fixnum index count))
- (if (char= (schar string index) #\newline)
- (return count))))
- (:element-type (array-element-type (string-output-stream-string stream)))))
+ ;; Keeping this first is a silly micro-optimization: FRESH-LINE
+ ;; makes this the most common one.
+ (/show0 "/string-out-misc charpos")
+ (prog ((pointer (string-output-stream-pointer stream))
+ (buffer (string-output-stream-buffer stream))
+ (prev (string-output-stream-prev stream))
+ (base 0))
+ :next
+ (let ((pos (position #\newline buffer :from-end t :end pointer)))
+ (when (or pos (not buffer))
+ ;; If newline is at index I, and pointer at index I+N, charpos
+ ;; is N-1. If there is no newline, and pointer is at index N,
+ ;; charpos is N.
+ (return (+ base (if pos (- pointer pos 1) pointer))))
+ (setf base (+ base pointer)
+ buffer (pop prev)
+ pointer (length buffer))
+ (/show0 "/string-out-misc charpos next")
+ (go :next))))
+ (:file-position
+ (/show0 "/string-out-misc file-position")
+ (when arg1
+ (set-string-output-stream-file-position stream arg1))
+ (string-output-stream-index stream))
+ (:close
+ (/show0 "/string-out-misc close")
+ (set-closed-flame stream))
+ (:element-type (string-output-stream-element-type stream))))
;;; Return a string of all the characters sent to a stream made by
;;; MAKE-STRING-OUTPUT-STREAM since the last call to this function.
(defun get-output-stream-string (stream)
(declare (type string-output-stream stream))
- (let* ((length (string-output-stream-last-index stream))
+ (let* ((length (max (string-output-stream-index stream)
+ (string-output-stream-index-cache stream)))
(element-type (string-output-stream-element-type stream))
+ (prev (string-output-stream-prev stream))
+ (this (string-output-stream-buffer stream))
+ (next (string-output-stream-next stream))
(result
(case element-type
;; overwhelmingly common case: can be inlined
+ ;;
+ ;; FIXME: If we were willing to use %SHRINK-VECTOR here,
+ ;; and allocate new strings the size of 2 * index in
+ ;; STRING-SOUT, we would not need to allocate one here in
+ ;; the common case, but could just use the last one
+ ;; allocated, and chop it down to size..
+ ;;
((character) (make-string length))
;; slightly less common cases: inline it anyway
((base-char standard-char)
(make-string length :element-type 'base-char))
- (t (make-string length :element-type element-type)))))
- ;; For the benefit of the REPLACE transform, let's do this, so
- ;; that the common case isn't ludicrously expensive.
- (etypecase result
- ((simple-array character (*))
- (replace result (string-output-stream-string stream)))
- (simple-base-string
- (replace result (string-output-stream-string stream)))
- ((simple-array nil (*))
- (replace result (string-output-stream-string stream))))
+ (t
+ (make-string length :element-type element-type)))))
+
(setf (string-output-stream-index stream) 0
- (string-output-stream-index-cache stream) 0)
- result))
+ (string-output-stream-index-cache stream) 0
+ (string-output-stream-pointer stream) 0
+ ;; throw them away for simplicity's sake: this way the rest of the
+ ;; implementation can assume that the greater of INDEX and INDEX-CACHE
+ ;; is always within the last buffer.
+ (string-output-stream-prev stream) nil
+ (string-output-stream-next stream) nil)
+
+ (flet ((replace-all (fun)
+ (let ((start 0))
+ (declare (index start))
+ (dolist (buffer (nreverse prev))
+ (funcall fun buffer start)
+ (incf start (length buffer)))
+ (funcall fun this start)
+ (incf start (length this))
+ (dolist (buffer next)
+ (funcall fun buffer start)
+ (incf start (length buffer))))))
+ (macrolet ((frob (type)
+ `(replace-all (lambda (buffer from)
+ (declare (type ,type result)
+ (type (simple-array character (*))
+ buffer))
+ (replace result buffer :start1 from)))))
+ (etypecase result
+ ((simple-array character (*))
+ (frob (simple-array character (*))))
+ (simple-base-string
+ (frob simple-base-string))
+ ((simple-array nil (*))
+ (frob (simple-array nil (*)))))))
-;;; Dump the characters buffer up in IN-STREAM to OUT-STREAM as
-;;; GET-OUTPUT-STREAM-STRING would return them.
-(defun dump-output-stream-string (in-stream out-stream)
- (%write-string (string-output-stream-string in-stream)
- out-stream
- 0
- (string-output-stream-last-index in-stream))
- (setf (string-output-stream-index in-stream) 0
- (string-output-stream-index-cache in-stream) 0))
+ result))
\f
;;;; fill-pointer streams
projects / sbcl.git / commitdiff