0.8.1.21:
[sbcl.git] / src / code / stream.lisp
index 19cde5e..aa91999 100644 (file)
 
 (in-package "SB!IMPL")
 
-(deftype string-stream ()
-  '(or string-input-stream string-output-stream
-       fill-pointer-output-stream))
-
 ;;;; standard streams
 
 ;;; The initialization of these streams is performed by
 (defun closed-flame (stream &rest ignore)
   (declare (ignore ignore))
   (error "~S is closed." stream))
-(defun do-nothing (&rest ignore)
+(defun no-op-placeholder (&rest ignore)
   (declare (ignore ignore)))
 \f
 ;;; stream manipulation functions
 
-(defun input-stream-p (stream)
-  (declare (type stream stream))
+(declaim (inline ansi-stream-input-stream-p))
+(defun ansi-stream-input-stream-p (stream)
+  (declare (type ansi-stream stream))
 
   #!+high-security
   (when (synonym-stream-p stream)
     (setf stream
          (symbol-value (synonym-stream-symbol stream))))
 
-  (and (ansi-stream-p stream)
-       (not (eq (ansi-stream-in stream) #'closed-flame))
+  (and (not (eq (ansi-stream-in stream) #'closed-flame))
        ;;; KLUDGE: It's probably not good to have EQ tests on function
        ;;; values like this. What if someone's redefined the function?
        ;;; Is there a better way? (Perhaps just VALID-FOR-INPUT and
        (or (not (eq (ansi-stream-in stream) #'ill-in))
           (not (eq (ansi-stream-bin stream) #'ill-bin)))))
 
-(defun output-stream-p (stream)
+(defun input-stream-p (stream)
   (declare (type stream stream))
+  (and (ansi-stream-p stream)
+       (ansi-stream-input-stream-p stream)))
+
+(declaim (inline ansi-stream-output-stream-p))
+(defun ansi-stream-output-stream-p (stream)
+  (declare (type ansi-stream stream))
 
   #!+high-security
   (when (synonym-stream-p stream)
     (setf stream (symbol-value
                  (synonym-stream-symbol stream))))
 
-  (and (ansi-stream-p stream)
-       (not (eq (ansi-stream-in stream) #'closed-flame))
+  (and (not (eq (ansi-stream-in stream) #'closed-flame))
        (or (not (eq (ansi-stream-out stream) #'ill-out))
           (not (eq (ansi-stream-bout stream) #'ill-bout)))))
 
-(defun open-stream-p (stream)
+(defun output-stream-p (stream)
   (declare (type stream stream))
+
+  (and (ansi-stream-p stream)
+       (ansi-stream-output-stream-p stream)))
+
+(declaim (inline ansi-stream-open-stream-p))
+(defun ansi-stream-open-stream-p (stream)
+  (declare (type ansi-stream stream))
   (not (eq (ansi-stream-in stream) #'closed-flame)))
 
-(defun stream-element-type (stream)
-  (declare (type stream stream))
+(defun open-stream-p (stream)
+  (ansi-stream-open-stream-p stream))
+
+(declaim (inline ansi-stream-element-type))
+(defun ansi-stream-element-type (stream)
+  (declare (type ansi-stream stream))
   (funcall (ansi-stream-misc stream) stream :element-type))
 
+(defun stream-element-type (stream)
+  (ansi-stream-element-type stream))
+
 (defun interactive-stream-p (stream)
   (declare (type stream stream))
   (funcall (ansi-stream-misc stream) stream :interactive-p))
 
-(defun close (stream &key abort)
-  (declare (type stream stream))
+(declaim (inline ansi-stream-close))
+(defun ansi-stream-close (stream abort)
+  (declare (type ansi-stream stream))
   (when (open-stream-p stream)
     (funcall (ansi-stream-misc stream) stream :close abort))
   t)
 
+(defun close (stream &key abort)
+  (ansi-stream-close stream abort))
+
 (defun set-closed-flame (stream)
   (setf (ansi-stream-in stream) #'closed-flame)
   (setf (ansi-stream-bin stream) #'closed-flame)
           ;; private predicate function..) is ugly and confusing, but
           ;; I can't see any other way. -- WHN 2001-04-14
           :expected-type '(satisfies stream-associated-with-file-p)
-          :format-string
+          :format-control
           "~@<The stream ~2I~_~S ~I~_isn't associated with a file.~:>"
           :format-arguments (list stream))))
 
 ;;; like FILE-POSITION, only using :FILE-LENGTH
 (defun file-length (stream)
-  (declare (type (or file-stream synonym-stream) stream))
+  ;; FIXME: The following declaration uses yet undefined types, which
+  ;; cause cross-compiler hangup.
+  ;;
+  ;; (declare (type (or file-stream synonym-stream) stream))
   (stream-must-be-associated-with-file stream)
   (funcall (ansi-stream-misc stream) stream :file-length))
 \f
        (stream-unread-char stream character)))
   nil)
 
+
+;;; In the interest of ``once and only once'' this macro contains the
+;;; framework necessary to implement a peek-char function, which has
+;;; two special-cases (one for gray streams and one for echo streams)
+;;; in addition to the normal case.
+;;;
+;;; All arguments are forms which will be used for a specific purpose
+;;; PEEK-TYPE - the current peek-type as defined by ANSI CL
+;;; EOF-VALUE - the eof-value argument to peek-char
+;;; CHAR-VAR - the variable which will be used to store the current character
+;;; READ-FORM - the form which will be used to read a character
+;;; UNREAD-FORM - ditto for unread-char
+;;; SKIPPED-CHAR-FORM - the form to execute when skipping a character
+;;; EOF-DETECTED-FORM - the form to execute when EOF has been detected
+;;;                     (this will default to CHAR-VAR)
+(defmacro generalized-peeking-mechanism (peek-type eof-value char-var read-form unread-form &optional (skipped-char-form nil) (eof-detected-form nil))
+  `(let ((,char-var ,read-form))
+    (cond ((eql ,char-var ,eof-value) 
+          ,(if eof-detected-form
+               eof-detected-form
+               char-var))
+         ((characterp ,peek-type)
+          (do ((,char-var ,char-var ,read-form))
+              ((or (eql ,char-var ,eof-value) 
+                   (char= ,char-var ,peek-type))
+               (cond ((eql ,char-var ,eof-value)
+                      ,(if eof-detected-form
+                           eof-detected-form
+                           char-var))
+                     (t ,unread-form
+                        ,char-var)))
+            ,skipped-char-form))
+         ((eql ,peek-type t)
+          (do ((,char-var ,char-var ,read-form))
+              ((or (eql ,char-var ,eof-value)
+                   (not (whitespace-char-p ,char-var)))
+               (cond ((eql ,char-var ,eof-value)
+                      ,(if eof-detected-form
+                           eof-detected-form
+                           char-var))
+                     (t ,unread-form
+                        ,char-var)))
+            ,skipped-char-form))
+         ((null ,peek-type)
+          ,unread-form
+          ,char-var)
+         (t
+          (bug "Impossible case reached in PEEK-CHAR")))))
+
 (defun peek-char (&optional (peek-type nil)
                            (stream *standard-input*)
                            (eof-error-p t)
           :format-control "~@<bad PEEK-TYPE=~S, ~_expected ~S~:>"
           :format-arguments (list peek-type '(or character boolean))))
   (let ((stream (in-synonym-of stream)))
-    (if (ansi-stream-p stream)
-       (let ((char (read-char stream eof-error-p eof-value)))
-         (cond ((eq char eof-value) char)
-               ((characterp peek-type)
-                (do ((char char (read-char stream eof-error-p eof-value)))
-                    ((or (eq char eof-value) (char= char peek-type))
-                     (unless (eq char eof-value)
-                       (unread-char char stream))
-                     char)))
-               ((eq peek-type t)
-                (do ((char char (read-char stream eof-error-p eof-value)))
-                    ((or (eq char eof-value) (not (whitespace-char-p char)))
-                     (unless (eq char eof-value)
-                       (unread-char char stream))
-                     char)))
-               ((null peek-type)
-                (unread-char char stream)
-                char)
-               (t
-                (error "internal error: impossible case"))))
-       ;; by elimination, must be Gray streams FUNDAMENTAL-STREAM
-       (cond ((characterp peek-type)
-              (do ((char (stream-read-char stream)
-                         (stream-read-char stream)))
-                  ((or (eq char :eof) (char= char peek-type))
-                   (cond ((eq char :eof)
-                          (eof-or-lose stream eof-error-p eof-value))
-                         (t
-                          (stream-unread-char stream char)
-                          char)))))
-             ((eq peek-type t)
-              (do ((char (stream-read-char stream)
-                         (stream-read-char stream)))
-                  ((or (eq char :eof) (not (whitespace-char-p char)))
-                   (cond ((eq char :eof)
-                          (eof-or-lose stream eof-error-p eof-value))
-                         (t
-                          (stream-unread-char stream char)
-                          char)))))
-             ((null peek-type)
-              (let ((char (stream-peek-char stream)))
-                (if (eq char :eof)
-                    (eof-or-lose stream eof-error-p eof-value)
-                    char)))
-             (t
-              (error "internal error: impossible case"))))))
+    (cond ((typep stream 'echo-stream)
+          (echo-misc stream 
+                     :peek-char
+                     peek-type
+                     (list eof-error-p eof-value)))
+         ((ansi-stream-p stream)
+          (generalized-peeking-mechanism
+           peek-type eof-value char
+           (read-char stream eof-error-p eof-value)
+           (unread-char char stream)))
+         (t
+          ;; by elimination, must be Gray streams FUNDAMENTAL-STREAM
+          (generalized-peeking-mechanism
+           peek-type :eof char
+           (if (null peek-type)
+               (stream-peek-char stream)
+               (stream-read-char stream))
+           (if (null peek-type)
+               ()
+               (stream-unread-char stream char))
+           ()
+           (eof-or-lose stream eof-error-p eof-value))))))
 
 (defun listen (&optional (stream *standard-input*))
   (let ((stream (in-synonym-of stream)))
        (stream-fresh-line stream))))
 
 (defun write-string (string &optional (stream *standard-output*)
-                           &key (start 0) (end nil))
-  (%write-string string stream start (or end (length string)))
-  string)
-
-(defun %write-string (string stream start end)
+                           &key (start 0) end)
   (declare (type string string))
-  (declare (type streamlike stream))
-  (declare (type index start end))
-
   ;; Note that even though you might expect, based on the behavior of
   ;; things like AREF, that the correct upper bound here is
   ;; (ARRAY-DIMENSION STRING 0), the ANSI glossary definitions for
   ;; "bounding index" and "length" indicate that in this case (i.e.
-  ;; for the ANSI-specified functions WRITE-STRING and WRITE-LINE
-  ;; which are implemented in terms of this function), (LENGTH STRING)
-  ;; is the required upper bound. A foolish consistency is the
-  ;; hobgoblin of lesser languages..
-  (unless (<= 0 start end (length string))
-    (error "~@<bad bounding indices START=~W END=~W for ~2I~_~S~:>"
-          start
-          end
-          string))
+  ;; for the ANSI-specified functions WRITE-STRING [and WRITE-LINE]),
+  ;; (LENGTH STRING) is the required upper bound. A foolish
+  ;; consistency is the hobgoblin of lesser languages..
+  (%write-string string stream start (%check-vector-sequence-bounds
+                                     string start end))
+  string)
 
+(defun %write-string (string stream start end)
+  (declare (type string string))
+  (declare (type streamlike stream))
+  (declare (type index start end))
   (let ((stream (out-synonym-of stream)))
     (cond ((ansi-stream-p stream)
           (if (array-header-p string)
           (stream-write-string stream string start end)))))
 
 (defun write-line (string &optional (stream *standard-output*)
-                         &key (start 0) (end nil))
-  (let ((defaulted-stream (out-synonym-of stream))
-       (defaulted-end (or end (length string))))
-    (%write-string string defaulted-stream start defaulted-end)
+                         &key (start 0) end)
+  (declare (type string string))
+  ;; FIXME: Why is there this difference between the treatments of the
+  ;; STREAM argument in WRITE-STRING and WRITE-LINE?
+  (let ((defaulted-stream (out-synonym-of stream)))
+    (%write-string string defaulted-stream start (%check-vector-sequence-bounds
+                                                 string start end))
     (write-char #\newline defaulted-stream))
   string)
 
                                       (bout #'broadcast-bout)
                                       (sout #'broadcast-sout)
                                       (misc #'broadcast-misc))
-                            (:constructor #!-high-security-support
-                                          make-broadcast-stream
-                                          #!+high-security-support
-                                          %make-broadcast-stream (&rest
-                                                                  streams))
+                            (:constructor %make-broadcast-stream
+                                          (&rest streams))
                             (:copier nil))
   ;; a list of all the streams we broadcast to
   (streams () :type list :read-only t))
 
-#!+high-security-support
 (defun make-broadcast-stream (&rest streams)
   (dolist (stream streams)
     (unless (or (and (synonym-stream-p stream)
                      (bout #'two-way-bout)
                      (sout #'two-way-sout)
                      (misc #'two-way-misc))
-           (:constructor #!-high-security-support
-                         make-two-way-stream
-                         #!+high-security-support
-                         %make-two-way-stream (input-stream output-stream))
+           (:constructor %make-two-way-stream (input-stream output-stream))
            (:copier nil))
   (input-stream (missing-arg) :type stream :read-only t)
   (output-stream (missing-arg) :type stream :read-only t))
 (defprinter (two-way-stream) input-stream output-stream)
 
-#!-high-security-support
-(setf (fdocumentation 'make-two-way-stream 'function)
-  "Return a bidirectional stream which gets its input from Input-Stream and
-   sends its output to Output-Stream.")
-#!+high-security-support
 (defun make-two-way-stream (input-stream output-stream)
   #!+sb-doc
-  "Return a bidirectional stream which gets its input from Input-Stream and
-   sends its output to Output-Stream."
+  "Return a bidirectional stream which gets its input from INPUT-STREAM and
+   sends its output to OUTPUT-STREAM."
   ;; FIXME: This idiom of the-real-stream-of-a-possibly-synonym-stream
   ;; should be encapsulated in a function, and used here and most of
   ;; the other places that SYNONYM-STREAM-P appears.
                      (bin #'concatenated-bin)
                      (n-bin #'concatenated-n-bin)
                      (misc #'concatenated-misc))
-           (:constructor
-            #!-high-security-support make-concatenated-stream
-            #!+high-security-support %make-concatenated-stream
-                (&rest streams &aux (current streams)))
+           (:constructor %make-concatenated-stream
+                         (&rest streams &aux (current streams)))
            (:copier nil))
   ;; The car of this is the substream we are reading from now.
   current
            ":STREAMS ~S"
            (concatenated-stream-streams x))))
 
-#!-high-security-support
-(setf (fdocumentation 'make-concatenated-stream 'function)
-  "Return a stream which takes its input from each of the Streams in turn,
-   going on to the next at EOF.")
-
-#!+high-security-support
 (defun make-concatenated-stream (&rest streams)
   #!+sb-doc
-  "Return a stream which takes its input from each of the Streams in turn,
+  "Return a stream which takes its input from each of the streams in turn,
    going on to the next at EOF."
   (dolist (stream streams)
     (unless (or (and (synonym-stream-p stream)
                  (let* ((stream (car current))
                         (result (,fun stream nil nil)))
                    (when result (return result)))
-                 (setf (concatenated-stream-current stream) current)))))
+                 (pop (concatenated-stream-current stream))))))
   (in-fun concatenated-in read-char)
   (in-fun concatenated-bin read-byte))
 
                      (bin #'echo-bin)
                      (misc #'echo-misc)
                      (n-bin #'ill-bin))
-           (:constructor make-echo-stream (input-stream output-stream))
+           (:constructor %make-echo-stream (input-stream output-stream))
            (:copier nil))
   unread-stuff)
 (def!method print-object ((x echo-stream) stream)
            (two-way-stream-input-stream x)
            (two-way-stream-output-stream x))))
 
+(defun make-echo-stream (input-stream output-stream)
+  #!+sb-doc
+  "Return a bidirectional stream which gets its input from INPUT-STREAM and
+   sends its output to OUTPUT-STREAM. In addition, all input is echoed to
+   the output stream."
+  (unless (or (and (synonym-stream-p output-stream)
+                  (output-stream-p (symbol-value
+                                    (synonym-stream-symbol output-stream))))
+             (output-stream-p output-stream))
+    (error 'type-error
+          :datum output-stream
+          :expected-type '(satisfies output-stream-p)))
+  (unless (or (and (synonym-stream-p input-stream)
+                  (input-stream-p (symbol-value
+                                   (synonym-stream-symbol input-stream))))
+             (input-stream-p input-stream))
+    (error 'type-error
+          :datum input-stream
+          :expected-type '(satisfies input-stream-p)))
+  (funcall #'%make-echo-stream input-stream output-stream))
+
 (macrolet ((in-fun (name fun out-slot stream-method &rest args)
             `(defun ,name (stream ,@args)
                (or (pop (echo-stream-unread-stuff stream))
             in-type `(and ,in-type ,out-type))))
       (:close
        (set-closed-flame stream))
+      (:peek-char
+       ;; For the special case of peeking into an echo-stream
+       ;; arg1 is PEEK-TYPE, arg2 is (EOF-ERROR-P EOF-VALUE)
+       ;; returns peeked-char, eof-value, or errors end-of-file
+       ;;
+       ;; Note: This code could be moved into PEEK-CHAR if desired.
+       ;; I am unsure whether this belongs with echo-streams because it is
+       ;; echo-stream specific, or PEEK-CHAR because it is peeking code.
+       ;; -- mrd 2002-11-18
+       ;;
+       ;; UNREAD-CHAR-P indicates whether the current character was one
+       ;; that was previously unread.  In that case, we need to ensure that
+       ;; the semantics for UNREAD-CHAR are held; the character should
+       ;; not be echoed again.
+       (let ((unread-char-p nil))
+        (flet ((outfn (c)
+                 (unless unread-char-p
+                   (if (ansi-stream-p out)
+                       (funcall (ansi-stream-out out) out c)
+                       ;; gray-stream
+                       (stream-write-char out c))))
+               (infn ()
+                 ;; Obtain input from unread buffer or input stream,
+                 ;; and set the flag appropriately.
+                 (cond ((not (null (echo-stream-unread-stuff stream)))
+                        (setf unread-char-p t)
+                        (pop (echo-stream-unread-stuff stream)))
+                       (t
+                        (setf unread-char-p nil)
+                        (read-char in (first arg2) (second arg2))))))
+          (generalized-peeking-mechanism
+           arg1 (second arg2) char
+           (infn)
+           (unread-char char in)
+           (outfn char)))))
       (t
        (or (if (ansi-stream-p in)
               (funcall (ansi-stream-misc in) in operation arg1 arg2)
           (if (ansi-stream-p out)
               (funcall (ansi-stream-misc out) out operation arg1 arg2)
               (stream-misc-dispatch out operation arg1 arg2)))))))
+\f
+;;;; base STRING-STREAM stuff
 
-#!+sb-doc
-(setf (fdocumentation 'make-echo-stream 'function)
-  "Return a bidirectional stream which gets its input from INPUT-STREAM and
-   sends its output to OUTPUT-STREAM. In addition, all input is echoed to
-   the output stream")
+(defstruct (string-stream
+             (:include ansi-stream)
+             (:constructor nil)
+             (:copier nil))
+  (string nil :type string))
 \f
-;;;; string input streams
+;;;; STRING-INPUT-STREAM stuff
 
 (defstruct (string-input-stream
-            (:include ansi-stream
+            (:include string-stream
                       (in #'string-inch)
                       (bin #'string-binch)
                       (n-bin #'string-stream-read-n-bytes)
-                      (misc #'string-in-misc))
+                      (misc #'string-in-misc)
+                       (string nil :type simple-string))
             (:constructor internal-make-string-input-stream
                           (string current end))
             (:copier nil))
-  (string nil :type simple-string)
   (current nil :type index)
   (end nil :type index))
 
     (:element-type 'base-char)))
 
 (defun make-string-input-stream (string &optional
-                                       (start 0) (end (length string)))
+                                       (start 0) end)
   #!+sb-doc
   "Return an input stream which will supply the characters of STRING between
   START and END in order."
   (declare (type string string)
           (type index start)
           (type (or index null) end))
-
-  #!+high-security
-  (when (> end (length string))
-    (cerror "Continue with end changed from ~S to ~S"
-           "Write-string: end (~S) is larger then the length of the string (~S)"
-           end (1- (length string))))
-
-  (internal-make-string-input-stream (coerce string 'simple-string)
-                                    start end))
+  
+  (internal-make-string-input-stream
+   (coerce string 'simple-string)
+   start
+   (%check-vector-sequence-bounds string start end)))
 \f
-;;;; string output streams
+;;;; STRING-OUTPUT-STREAM stuff
 
 (defstruct (string-output-stream
-           (:include ansi-stream
+           (:include string-stream
                      (out #'string-ouch)
                      (sout #'string-sout)
-                     (misc #'string-out-misc))
+                     (misc #'string-out-misc)
+                      ;; The string we throw stuff in.
+                      (string (make-string 40) :type simple-string))
            (:constructor make-string-output-stream ())
            (:copier nil))
-  ;; The string we throw stuff in.
-  (string (make-string 40) :type simple-string)
   ;; Index of the next location to use.
   (index 0 :type fixnum))
 
 ;;; the CLM, but they are required for the implementation of
 ;;; WITH-OUTPUT-TO-STRING.
 
+(deftype string-with-fill-pointer ()
+  '(and string
+       (satisfies array-has-fill-pointer-p)))
+
 (defstruct (fill-pointer-output-stream
-           (:include ansi-stream
+           (:include string-stream
                      (out #'fill-pointer-ouch)
                      (sout #'fill-pointer-sout)
-                     (misc #'fill-pointer-misc))
+                     (misc #'fill-pointer-misc)
+                      ;; a string with a fill pointer where we stuff
+                      ;; the stuff we write
+                      (string (error "missing argument")
+                              :type string-with-fill-pointer
+                              :read-only t))
            (:constructor make-fill-pointer-output-stream (string))
-           (:copier nil))
-  ;; the string we throw stuff in
-  string)
+           (:copier nil)))
 
 (defun fill-pointer-ouch (stream character)
   (let* ((buffer (fill-pointer-output-stream-string stream))
 
 (defstruct (case-frob-stream
            (:include ansi-stream
-                     (:misc #'case-frob-misc))
+                     (misc #'case-frob-misc))
            (:constructor %make-case-frob-stream (target out sout))
            (:copier nil))
   (target (missing-arg) :type stream))
        (funcall (ansi-stream-sout target) target str 0 len)
        (stream-write-string target str 0 len))))
 \f
-;;;; stream commands
-
-(defstruct (stream-command (:constructor make-stream-command
-                                        (name &optional args))
-                          (:copier nil))
-  (name nil :type symbol)
-  (args nil :type list))
-(def!method print-object ((obj stream-command) str)
-  (print-unreadable-object (obj str :type t :identity t)
-    (prin1 (stream-command-name obj) str)))
-
-;;; Take a stream and wait for text or a command to appear on it. If
-;;; text appears before a command, return NIL, otherwise return a
-;;; command.
-;;;
-;;; We can't simply call the stream's misc method because NIL is an
-;;; ambiguous return value: does it mean text arrived, or does it mean
-;;; the stream's misc method had no :GET-COMMAND implementation? We
-;;; can't return NIL until there is text input. We don't need to loop
-;;; because any stream implementing :GET-COMMAND would wait until it
-;;; had some input. If the LISTEN fails, then we have some stream we
-;;; must wait on.
-(defun get-stream-command (stream)
-  (let ((cmdp (funcall (ansi-stream-misc stream) stream :get-command)))
-    (cond (cmdp)
-         ((listen stream)
-          nil)
-         (t
-          ;; This waits for input and returns NIL when it arrives.
-          (unread-char (read-char stream) stream)))))
-\f
 ;;;; READ-SEQUENCE
 
-(defun read-sequence (seq stream &key (start 0) (end nil))
+(defun read-sequence (seq stream &key (start 0) end)
   #!+sb-doc
   "Destructively modify SEQ by reading elements from STREAM.
   That part of SEQ bounded by START and END is destructively modified by