Artifact 3e924ab62b1ae155f84ebc34fc9d790049a043cc02afe8bc5a4769e67b941c12:

• File psl-1983/emode/new-fileio.sl — part of check-in [eb17ceb7f6] at 2020-04-21 19:40:01 on branch master — Add Reduce 3.0 to the historical section of the archive, and some more
  files relating to version sof PSL from the early 1980s. Thanks are due to
  Paul McJones and Nelson Beebe for these, as well as to all the original
  authors.

  git-svn-id: https://svn.code.sf.net/p/reduce-algebra/code/historical@5328 2bfe0521-f11c-4a00-b80e-6202646ff360 (user: arthurcnorman@users.sourceforge.net, size: 3245) [annotate] [blame] [check-ins using] [more...]

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% New-FileIO.SL
% 
% Author:      Alan Snyder
%              Hewlett-Packard/CRC
% Date:        30 July 1982
%
% Revised File I/O for EMODE.
%
% The combination of buffered file input and string-oriented reading of the
% file into the buffer makes for a 5X improvement in the speed of reading a
% nontrivial file (or more, since it no longer does unnecessary consing).
% In addition, the ^Z EOF bug has been fixed.
%
% A similar speedup has been made to file output.  In addition, an extra
% blank line is no longer written at the end of each file.
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

(CompileTime (load objects))
(load input-stream output-stream fast-vector)

(de readfile (file-name)
  (write-prompt "")
  (let* ((p (ErrorSet (List 'open-input file-name) NIL NIL))
	 )
    (if (PairP p)
	(read-file-into-buffer (car p))
	(write-prompt (BldMsg "Unable to read file: %w" file-name))
	(Ding)
	)))

(de read-file-into-buffer (s)
  (write-prompt (BldMsg "Reading file: %w" (=> s file-name)))
  (setf CurrentBufferText (MkVect 1))
  (setf CurrentBufferSize 1)
  (append-file-to-buffer s)
  (=> s close)
  (write-prompt (BldMsg "File read: %w (%d lines)"
			(=> s file-name)
			(current-buffer-visible-size)))
  )

(de append-file-to-buffer (s)
  (prog (line-buffer line-size ch)
    (setf line-buffer (MkString 200 0))
    (while T
      (setf line-size 0)
      (setf ch (input-stream$getc s))
      (while (not (or (null ch) (WEq ch (char EOL))))
	(if (WGreaterP line-size (ISizeS line-buffer))
	  (setf line-buffer (concat line-buffer (Mkstring 200 0)))
	  )
	(iputs line-buffer line-size ch)
	(setf line-size (WPlus2 line-size 1))
	(setf ch (input-stream$getc s))
	)
      (if (not (and (null ch) (WEq line-size 0)))
	(append-line-to-buffer (sub line-buffer 0 (WDifference line-size 1)))
	)
      (cond ((null ch)
	     (if (> line-size 0)
		 (setf CurrentBufferSize (- CurrentBufferSize 1))
		 )
	     (exit)))
      )
    (GetLine (setf CurrentLineIndex 0))
    ))

(de append-line-to-buffer (contents)
  % Note: GETLINE must be done after a sequence of appends
  (let ((indx CurrentBufferSize))
    (setf CurrentBufferSize (+ CurrentBufferSize 1))
    (if (> CurrentBufferSize (size CurrentBufferText))
      (setf CurrentBufferText (concat CurrentBufferText (MkVect 63))))
    (SetBufferText (- indx 1) contents)
    (SetBufferText indx "")
    ))

(de WriteFile (file-name)
  % Write whole of current EMODE buffer to file.
  (write-prompt "")
  (let* ((p (ErrorSet (list 'open-output file-name) NIL NIL))
	 )
    (if (PairP p)
      (let ((s (car p)))
	   (write-prompt (BldMsg "Writing file: %w" (=> s file-name)))
	   (write-buffer-to-stream s)
	   (=> s close)
	   (write-prompt (BldMsg "File written: %w (%d lines)"
				 (=> s file-name)
				 (current-buffer-visible-size)))
	   )
      (write-prompt (BldMsg "Unable to write file: %w" file-name))
      (Ding)
      )))

(de write-buffer-to-stream (s)
  (PutLine CurrentLineIndex)
  (for (from i 0 (- CurrentBufferSize 2) 1)
       (do (output-stream$putl s (GetBufferText i)))
       )
  (output-stream$puts s (GetBufferText (- CurrentBufferSize 1)))
  )