Import SLIB 2d1.

module/slib/comparse.scm

@@ -0,0 +1,99 @@
+;;; "comparse.scm" Break command line into arguments.
+;Copyright (C) 1995, 1997 Aubrey Jaffer
+;
+;Permission to copy this software, to redistribute it, and to use it
+;for any purpose is granted, subject to the following restrictions and
+;understandings.
+;
+;1.  Any copy made of this software must include this copyright notice
+;in full.
+;
+;2.  I have made no warrantee or representation that the operation of
+;this software will be error-free, and I am under no obligation to
+;provide any services, by way of maintenance, update, or otherwise.
+;
+;3.  In conjunction with products arising from the use of this
+;material, there shall be no use of my name in any advertising,
+;promotional, or sales literature without prior written consent in
+;each case.
+
+;;;; This is a simple command-line reader.  It could be made fancier
+;;; to handle lots of `shell' syntaxes.
+
+;;; Albert L. Ting points out that a similar process can be used for
+;;; reading files of options -- therefore READ-OPTIONS-FILE.
+
+(require 'string-port)
+(define (read-command-from-port port nl-term?)
+  (define argv '())
+  (define obj "")
+  (define chars '())
+  (define readc (lambda () (read-char port)))
+  (define peekc (lambda () (peek-char port)))
+  (define s-expression
+    (lambda ()
+      (splice-arg (call-with-output-string
+		   (lambda (p) (display (slib:eval (read port)) p))))))
+  (define backslash
+    (lambda (goto)
+      (readc)
+      (let ((c (readc)))
+	(cond ((eqv? #\newline c) (goto (peekc)))
+	      ((and (char-whitespace? c) (eqv? #\newline (peekc))
+		    (eqv? 13 (char->integer c)))
+	       (readc) (goto (peekc)))
+	      (else (set! chars (cons c chars)) (build-token (peekc)))))))
+  (define loop
+    (lambda (c)
+      (case c
+	((#\\) (backslash loop))
+	((#\") (splice-arg (read port)))
+	((#\( #\') (s-expression))
+	((#\#) (do ((c (readc) (readc)))
+		   ((or (eof-object? c) (eqv? #\newline c))
+		    (if nl-term? c (loop (peekc))))))
+	((#\;) (readc))
+	((#\newline) (readc) (and (not nl-term?) (loop (peekc))))
+	(else (cond ((eof-object? c) c)
+		    ((char-whitespace? c) (readc) (loop (peekc)))
+		    (else (build-token c)))))))
+  (define splice-arg
+    (lambda (arg)
+      (set! obj (string-append obj (list->string (reverse chars)) arg))
+      (set! chars '())
+      (build-token (peekc))))
+  (define buildit
+    (lambda ()
+      (readc)
+      (set! argv (cons (string-append obj (list->string (reverse chars)))
+		       argv))))
+  (define build-token
+    (lambda (c)
+      (case c
+	((#\") (splice-arg (read port)))
+	((#\() (s-expression))
+	((#\\) (backslash build-token))
+	((#\;) (buildit))
+	(else (cond ((or (eof-object? c) (char-whitespace? c))
+		     (buildit)
+		     (cond ((not (and nl-term? (eqv? c #\newline)))
+			    (set! obj "")
+			    (set! chars '())
+			    (loop (peekc)))))
+		    (else (set! chars (cons (readc) chars))
+			  (build-token (peekc))))))))
+  (let ((c (loop (peekc))))
+    (cond ((and (null? argv) (eof-object? c)) c)
+	  (else (reverse argv)))))
+
+(define (read-command . port)
+  (read-command-from-port (cond ((null? port) (current-input-port))
+				((= 1 (length port)) (car port))
+				(else
+				 (slib:error 'read-command
+					     "Wrong Number of ARGs:" port)))
+			  #t))
+
+(define (read-options-file filename)
+  (call-with-input-file filename
+    (lambda (port) (read-command-from-port port #f))))