contrib/sb-simple-streams/internal.lisp

   1 ;;; -*- Mode: LISP; Syntax: ANSI-Common-Lisp; Package: STREAM -*-
   2
   3 ;;; **********************************************************************
   4 ;;; This code was written by Paul Foley and has been placed in the public
   5 ;;; domain.
   6 ;;;
   7
   8 ;;; Sbcl port by Rudi Schlatte.
   9
  10 (in-package "SB-SIMPLE-STREAMS")
  11
  12 ;;;
  13 ;;; **********************************************************************
  14 ;;;
  15 ;;; Various functions needed by simple-streams
  16 (declaim (inline buffer-sap bref (setf bref) buffer-copy
  17                  allocate-buffer free-buffer))
  18
  19 (defun buffer-sap (thing &optional offset)
  20   (declare (type simple-stream-buffer thing) (type (or fixnum null) offset)
  21            (optimize (speed 3) (space 2) (debug 0) (safety 0)
  22                      ;; Suppress the note about having to box up the return:
  23                      (sb-ext:inhibit-warnings 3)))
  24   (let ((sap (if (vectorp thing) (sb-sys:vector-sap thing) thing)))
  25     (if offset (sb-sys:sap+ sap offset) sap)))
  26
  27 (defun bref (buffer index)
  28   (declare (type simple-stream-buffer buffer)
  29            (type (integer 0 #.most-positive-fixnum) index))
  30   (if (vectorp buffer)
  31       (sb-sys:with-pinned-objects (buffer)
  32         (sb-sys:sap-ref-8 (sb-sys:vector-sap buffer) index))
  33       (sb-sys:sap-ref-8 buffer index)))
  34
  35 (defun (setf bref) (octet buffer index)
  36   (declare (type (unsigned-byte 8) octet)
  37            (type simple-stream-buffer buffer)
  38            (type (integer 0 #.most-positive-fixnum) index))
  39   (if (vectorp buffer)
  40       (sb-sys:with-pinned-objects (buffer)
  41         (setf (sb-sys:sap-ref-8 (sb-sys:vector-sap buffer) index) octet))
  42       (setf (sb-sys:sap-ref-8 buffer index) octet)))
  43
  44 (defun buffer-copy (src soff dst doff length)
  45   (declare (type simple-stream-buffer src dst)
  46            (type fixnum soff doff length))
  47   ;; FIXME: Should probably be with-pinned-objects
  48   (sb-sys:without-gcing
  49    (sb-kernel:system-area-ub8-copy (buffer-sap src) soff
  50                                    (buffer-sap dst) doff
  51                                    length)))
  52
  53 (defun allocate-buffer (size)
  54   (make-array size :element-type '(unsigned-byte 8)))
  55
  56 (defun free-buffer (buffer)
  57   (sb-int:aver (typep buffer '(simple-array (unsigned-byte 8) (*))))
  58   t)
  59
  60 (defun make-control-table (&rest inits)
  61   (let ((table (make-array 32 :initial-element nil)))
  62     (do* ((char (pop inits) (pop inits))
  63           (func (pop inits) (pop inits)))
  64          ((null char))
  65       (when (< (char-code char) 32)
  66         (setf (aref table (char-code char)) func)))
  67     table))
  68
  69 (defun std-newline-out-handler (stream character)
  70   (declare (ignore character))
  71   (with-stream-class (simple-stream stream)
  72     (setf (sm charpos stream) -1)
  73     nil))
  74
  75 (defun std-tab-out-handler (stream character)
  76   (declare (ignore character))
  77   (with-stream-class (simple-stream stream)
  78     (let ((col (sm charpos stream)))
  79       (when col
  80         (setf (sm charpos stream) (1- (* 8 (1+ (floor col 8)))))))
  81     nil))
  82
  83 (defun std-dc-newline-in-handler (stream character)
  84   (with-stream-class (dual-channel-simple-stream stream)
  85     ;; FIXME: Currently, -1 is wrong, since callers of CHARPOS expect
  86     ;; a result in (or null (and fixnum unsigned-byte)), so they must
  87     ;; never see this temporary value.  Note that in
  88     ;; STD-NEWLINE-OUT-HANDLER it is correct to use -1, since CHARPOS
  89     ;; is incremented to zero before WRITE-CHAR returns.  Perhaps the
  90     ;; same should happen for input?
  91     (setf (sm charpos stream) 0) ; was -1
  92     character))
  93
  94 (defvar *std-control-out-table*
  95   (make-control-table #\Newline #'std-newline-out-handler
  96                       #\Tab     #'std-tab-out-handler))
  97
  98 (defvar *default-external-format* :iso8859-1)
  99
 100 (defvar *external-formats* (make-hash-table))
 101 (defvar *external-format-aliases* (make-hash-table))
 102
 103 (defstruct (external-format
 104              (:conc-name ef-)
 105              (:print-function %print-external-format)
 106              (:constructor make-external-format (name octets-to-char
 107                                                       char-to-octets)))
 108   (name (sb-int:missing-arg) :type keyword :read-only t)
 109   (octets-to-char (sb-int:missing-arg) :type function :read-only t)
 110   (char-to-octets (sb-int:missing-arg) :type function :read-only t))
 111
 112 (defun %print-external-format (ef stream depth)
 113   (declare (ignore depth))
 114   (print-unreadable-object (ef stream :type t :identity t)
 115     (princ (ef-name ef) stream)))
 116
 117 (defmacro define-external-format (name octets-to-char char-to-octets)
 118   `(macrolet ((octets-to-char ((state input unput) &body body)
 119                 `(lambda (,state ,input ,unput)
 120                    (declare (type (function () (unsigned-byte 8)) ,input)
 121                             (type (function (sb-int:index) t) ,unput)
 122                             (ignorable ,state ,input ,unput)
 123                             (values character sb-int:index t))
 124                    ,@body))
 125               (char-to-octets ((char state output) &body body)
 126                 `(lambda (,char ,state ,output)
 127                    (declare (type character ,char)
 128                             (type (function ((unsigned-byte 8)) t) ,output)
 129                             (ignorable state ,output)
 130                             (values t))
 131                    ,@body)))
 132      (setf (gethash ,name *external-formats*)
 133            (make-external-format ,name ,octets-to-char ,char-to-octets))))
 134
 135 ;;; TODO: make this work
 136 (defun load-external-format-aliases ()
 137   (let ((*package* (find-package "KEYWORD")))
 138     (with-open-file (stm "ef:aliases" :if-does-not-exist nil)
 139       (when stm
 140         (do ((alias (read stm nil stm) (read stm nil stm))
 141              (value (read stm nil stm) (read stm nil stm)))
 142             ((or (eq alias stm) (eq value stm))
 143              (unless (eq alias stm)
 144                (warn "External-format aliases file ends early.")))
 145           (if (and (keywordp alias) (keywordp value))
 146               (setf (gethash alias *external-format-aliases*) value)
 147               (warn "Bad entry in external-format aliases file: ~S => ~S."
 148                     alias value)))))))
 149
 150 (defun find-external-format (name &optional (error-p t))
 151   (when (external-format-p name)
 152     (return-from find-external-format name))
 153
 154   (when (eq name :default)
 155     (setq name *default-external-format*))
 156
 157   ;; TODO: make this work
 158   #+nil
 159   (unless (ext:search-list-defined-p "ef:")
 160     (setf (ext:search-list "ef:") '("library:ef/")))
 161
 162   (when (zerop (hash-table-count *external-format-aliases*))
 163     (setf (gethash :latin1 *external-format-aliases*) :iso8859-1)
 164     (setf (gethash :latin-1 *external-format-aliases*) :iso8859-1)
 165     (setf (gethash :iso-8859-1 *external-format-aliases*) :iso8859-1)
 166     (load-external-format-aliases))
 167
 168   (do ((tmp (gethash name *external-format-aliases*)
 169             (gethash tmp *external-format-aliases*))
 170        (cnt 0 (1+ cnt)))
 171       ((or (null tmp) (= cnt 50))
 172        (unless (null tmp)
 173          (error "External-format aliasing depth exceeded.")))
 174     (setq name tmp))
 175
 176   (or (gethash name *external-formats*)
 177       (and (let ((*package* (find-package "SB-SIMPLE-STREAMS")))
 178              (load (format nil "ef:~(~A~)" name) :if-does-not-exist nil))
 179            (gethash name *external-formats*))
 180       (if error-p (error "External format ~S not found." name) nil)))
 181
 182 (define-condition void-external-format (error)
 183   ()
 184   (:report
 185     (lambda (condition stream)
 186       (declare (ignore condition))
 187       (format stream "Attempting I/O through void external-format."))))
 188
 189 (define-external-format :void
 190     (octets-to-char (state input unput)
 191       (declare (ignore state input unput))
 192       (error 'void-external-format))
 193   (char-to-octets (char state output)
 194     (declare (ignore char state output))
 195     (error 'void-external-format)))
 196
 197 (define-external-format :iso8859-1
 198     (octets-to-char (state input unput)
 199       (declare (optimize (speed 3) (space 0) (safety 0) (debug 0)))
 200       (values (code-char (funcall input)) 1 state))
 201   (char-to-octets (char state output)
 202     (declare (optimize (speed 3) (space 0) (safety 0) (debug 0)))
 203     (let ((code (char-code char)))
 204       #-(or)
 205       (funcall output code)
 206       #+(or)
 207       (if (< code 256)
 208           (funcall output code)
 209           (funcall output (char-code #\?))))
 210     state))
 211
 212 (defmacro octets-to-char (external-format state count input unput)
 213   (let ((tmp1 (gensym)) (tmp2 (gensym)) (tmp3 (gensym)))
 214     `(multiple-value-bind (,tmp1 ,tmp2 ,tmp3)
 215          (funcall (ef-octets-to-char ,external-format) ,state ,input ,unput)
 216        (setf ,state ,tmp3 ,count ,tmp2)
 217        ,tmp1)))
 218
 219 (defmacro char-to-octets (external-format char state output)
 220   `(progn
 221      (setf ,state (funcall (ef-char-to-octets ,external-format)
 222                            ,char ,state ,output))
 223      nil))
 224
 225 (defun string-to-octets (string &key (start 0) end (external-format :default))
 226   (declare (type string string)
 227            (type sb-int:index start)
 228            (type (or null sb-int:index) end))
 229   (let ((ef (find-external-format external-format))
 230         (buffer (make-array (length string) :element-type '(unsigned-byte 8)))
 231         (ptr 0)
 232         (state nil))
 233     (flet ((out (b)
 234              (setf (aref buffer ptr) b)
 235              (when (= (incf ptr) (length buffer))
 236                (setq buffer (adjust-array buffer (* 2 ptr))))))
 237       (dotimes (i (- (or end (length string)) start))
 238         (declare (type sb-int:index i))
 239         (char-to-octets ef (char string (+ start i)) state #'out))
 240       (sb-kernel:shrink-vector buffer ptr))))
 241
 242 (defun octets-to-string (octets &key (start 0) end (external-format :default))
 243   (declare (type vector octets)
 244            (type sb-int:index start)
 245            (type (or null sb-int:index) end))
 246   (let ((ef (find-external-format external-format))
 247         (end (1- (or end (length octets))))
 248         (string (make-string (length octets)))
 249         (ptr (1- start))
 250         (pos -1)
 251         (count 0)
 252         (state nil))
 253     (flet ((input ()
 254              (aref octets (incf ptr)))
 255            (unput (n)
 256              (decf ptr n)))
 257       (loop until (>= ptr end)
 258             do (setf (schar string (incf pos))
 259                  (octets-to-char ef state count #'input #'unput))))
 260     (sb-kernel:shrink-vector string (1+ pos))))
 261
 262 (defun vector-elt-width (vector)
 263   ;; Return octet-width of vector elements
 264   (etypecase vector
 265     ;; (simple-array fixnum (*)) not supported
 266     ;; (simple-array base-char (*)) treated specially; don't call this
 267     ((simple-array bit (*)) 1)
 268     ((simple-array (unsigned-byte 2) (*)) 1)
 269     ((simple-array (unsigned-byte 4) (*)) 1)
 270     ((simple-array (signed-byte 8) (*)) 1)
 271     ((simple-array (unsigned-byte 8) (*)) 1)
 272     ((simple-array (signed-byte 16) (*)) 2)
 273     ((simple-array (unsigned-byte 16) (*)) 2)
 274     ((simple-array (signed-byte 32) (*)) 4)
 275     ((simple-array (unsigned-byte 32) (*)) 4)
 276     ((simple-array single-float (*)) 4)
 277     ((simple-array double-float (*)) 8)
 278     ((simple-array (complex single-float) (*)) 8)
 279     ((simple-array (complex double-float) (*)) 16)))
 280
 281 #-(or big-endian little-endian)
 282 (eval-when (:compile-toplevel)
 283   (push sb-c::*backend-byte-order* *features*))
 284
 285 (defun endian-swap-value (vector endian-swap)
 286   #+big-endian (declare (ignore vector))
 287   (case endian-swap
 288     (:network-order #+big-endian 0
 289                     #+little-endian (1- (vector-elt-width vector)))
 290     (:byte-8 0)
 291     (:byte-16 1)
 292     (:byte-32 3)
 293     (:byte-64 7)
 294     (:byte-128 15)
 295     (otherwise endian-swap)))
 296
 297 #+(or)
 298 (defun %read-vector (vector stream start end endian-swap blocking)
 299   (declare (type (kernel:simple-unboxed-array (*)) vector)
 300            (type stream stream))
 301   ;; move code from read-vector
 302   )
 303
 304 #+(or)
 305 (defun %write-vector (... blocking)
 306   ;; implement me
 307   )
 308
 309 (defun read-octets (stream buffer start end blocking)
 310   (declare (type simple-stream stream)
 311            (type (or null simple-stream-buffer) buffer)
 312            (type fixnum start)
 313            (type (or null fixnum) end)
 314            (type blocking blocking)
 315            (optimize (speed 3) (space 2) (safety 0) (debug 0)))
 316   (with-stream-class (simple-stream stream)
 317     (let ((fd (sm input-handle stream))
 318           (end (or end (sm buf-len stream)))
 319           (buffer (or buffer (sm buffer stream))))
 320       (declare (fixnum end))
 321       (typecase fd
 322         (fixnum
 323          (let ((flag (sb-sys:wait-until-fd-usable fd :input
 324                                                   (if blocking nil 0))))
 325            (cond
 326              ((and (not blocking) (= start end)) (if flag -3 0))
 327              ((and (not blocking) (not flag)) 0)
 328              (t (block nil
 329                   (let ((count 0))
 330                     (declare (type fixnum count))
 331                     (tagbody
 332                      again
 333                        ;; Avoid CMUCL gengc write barrier
 334                        (do ((i start (+ i #.(sb-posix:getpagesize))))
 335                            ((>= i end))
 336                          (declare (type fixnum i))
 337                          (setf (bref buffer i) 0))
 338                        (setf (bref buffer (1- end)) 0)
 339                        (multiple-value-bind (bytes errno)
 340                            (sb-sys:with-pinned-objects (buffer)
 341                              (sb-unix:unix-read fd (buffer-sap buffer start)
 342                                                 (the fixnum (- end start))))
 343                          (declare (type (or null fixnum) bytes)
 344                                   (type (integer 0 100) errno))
 345                          (when bytes
 346                            (incf count bytes)
 347                            (incf start bytes))
 348                          (cond ((null bytes)
 349                                 (format *debug-io* "~&;; UNIX-READ: errno=~D~%" errno)
 350                                 (cond ((= errno sb-unix:eintr) (go again))
 351                                       ((and blocking
 352                                             (or (= errno ;;sb-unix:eagain
 353                                                    ;; TODO: move
 354                                                    ;; eagain into
 355                                                    ;; sb-unix
 356                                                    11)
 357                                                 (= errno
 358                                                    #-win32
 359                                                    sb-unix:ewouldblock
 360                                                    #+win32
 361                                                    sb-unix:eintr)))
 362                                        (sb-sys:wait-until-fd-usable fd :input nil)
 363                                        (go again))
 364                                       (t (return (- -10 errno)))))
 365                                ((zerop count) (return -1))
 366                                (t (return count)))))))))))
 367         (t (%read-vector buffer fd start end :byte-8
 368                          (if blocking :bnb nil)))))))
 369
 370 (defun write-octets (stream buffer start end blocking)
 371   (declare (type simple-stream stream)
 372            (type simple-stream-buffer buffer)
 373            (type fixnum start)
 374            (type (or null fixnum) end))
 375   (with-stream-class (simple-stream stream)
 376     (when (sm handler stream)
 377       (do ()
 378           ((null (sm pending stream)))
 379         (sb-sys:serve-all-events)))
 380
 381     (let ((fd (sm output-handle stream))
 382           (end (or end (length buffer))))
 383       (typecase fd
 384         (fixnum
 385          (let ((flag (sb-sys:wait-until-fd-usable fd :output
 386                                                   (if blocking nil 0))))
 387            (cond
 388              ((and (not blocking) (= start end)) (if flag -3 0))
 389              ((and (not blocking) (not flag)) 0)
 390              (t
 391               (block nil
 392                 (let ((count 0))
 393                   (tagbody again
 394                      (multiple-value-bind (bytes errno)
 395                          (sb-sys:with-pinned-objects (buffer)
 396                            (sb-unix:unix-write fd (buffer-sap buffer) start
 397                                                (- end start)))
 398                        (when bytes
 399                          (incf count bytes)
 400                          (incf start bytes))
 401                        (cond ((null bytes)
 402                               (format *debug-io* "~&;; UNIX-WRITE: errno=~D~%" errno)
 403                               (cond ((= errno sb-unix:eintr) (go again))
 404                                     ;; don't block for subsequent chars
 405                                     (t (return (- -10 errno)))))
 406                              (t (return count)))))))))))
 407         (t (error "implement me"))))))
 408
 409 (defun do-some-output (stream)
 410   ;; Do some pending output; return T if completed, NIL if more to do
 411   (with-stream-class (simple-stream stream)
 412     (let ((fd (sm output-handle stream)))
 413       (loop
 414         (let ((list (pop (sm pending stream))))
 415           (unless list
 416             (sb-sys:remove-fd-handler (sm handler stream))
 417             (setf (sm handler stream) nil)
 418             (return t))
 419           (let* ((buffer (first list))
 420                  (start (second list))
 421                  (end (third list))
 422                  (len (- end start)))
 423             (declare (type simple-stream-buffer buffer)
 424                      (type sb-int:index start end len))
 425             (tagbody again
 426                (multiple-value-bind (bytes errno)
 427                    (sb-sys:with-pinned-objects (buffer)
 428                      (sb-unix:unix-write fd (buffer-sap buffer) start len))
 429                  (cond ((null bytes)
 430                         (if (= errno sb-unix:eintr)
 431                             (go again)
 432                             (progn (push list (sm pending stream))
 433                                    (return nil))))
 434                        ((< bytes len)
 435                         (setf (second list) (+ start bytes))
 436                         (push list (sm pending stream))
 437                         (return nil))
 438                        ((= bytes len)
 439                         (free-buffer buffer)))))))))))
 440
 441 (defun queue-write (stream buffer start end)
 442   ;; Queue a write; return T if buffer needs changing, NIL otherwise
 443   (declare (type simple-stream stream)
 444            (type simple-stream-buffer buffer)
 445            (type sb-int:index start end))
 446   (with-stream-class (simple-stream stream)
 447     (when (sm handler stream)
 448       (unless (do-some-output stream)
 449         (let ((last (last (sm pending stream))))
 450           (setf (cdr last) (list (list buffer start end)))
 451           (return-from queue-write t))))
 452     (let ((bytes (write-octets stream buffer start end nil)))
 453       (unless (or (= bytes (- end start)) ; completed
 454                   (= bytes -3)) ; empty buffer; shouldn't happen
 455         (setf (sm pending stream) (list (list buffer start end)))
 456         (setf (sm handler stream)
 457               (sb-sys:add-fd-handler (sm output-handle stream) :output
 458                                      (lambda (fd)
 459                                        (declare (ignore fd))
 460                                        (do-some-output stream))))
 461         t))))
 462
 463
 464
 465
 466 (defun %fd-open (pathname direction if-exists if-exists-given
 467                           if-does-not-exist if-does-not-exist-given)
 468   (declare (type pathname pathname)
 469            (type (member :input :output :io :probe) direction)
 470            (type (member :error :new-version :rename :rename-and-delete
 471                          :overwrite :append :supersede nil) if-exists)
 472            (type (member :error :create nil) if-does-not-exist))
 473   (multiple-value-bind (input output mask)
 474       (ecase direction
 475         (:input (values t nil sb-unix:o_rdonly))
 476         (:output (values nil t sb-unix:o_wronly))
 477         (:io (values t t sb-unix:o_rdwr))
 478         (:probe (values t nil sb-unix:o_rdonly)))
 479     (declare (type sb-int:index mask))
 480     (let* ((phys (sb-int:physicalize-pathname (merge-pathnames pathname)))
 481            (true (probe-file phys))
 482            (name (cond (true
 483                         (sb-ext:native-namestring true :as-file t))
 484                        ((or (not input)
 485                             (and input (eq if-does-not-exist :create))
 486                             (and (eq direction :io) (not if-does-not-exist-given)))
 487                         (sb-ext:native-namestring phys :as-file t)))))
 488       ;; Process if-exists argument if we are doing any output.
 489       (cond (output
 490              (unless if-exists-given
 491                (setf if-exists
 492                      (if (eq (pathname-version pathname) :newest)
 493                          :new-version
 494                          :error)))
 495              (case if-exists
 496                ((:error nil :new-version)
 497                 (setf mask (logior mask sb-unix:o_excl)))
 498                ((:rename :rename-and-delete)
 499                 (setf mask (logior mask sb-unix:o_creat)))
 500                ((:supersede)
 501                 (setf mask (logior mask sb-unix:o_trunc)))))
 502             (t
 503              (setf if-exists nil)))     ; :ignore-this-arg
 504       (unless if-does-not-exist-given
 505         (setf if-does-not-exist
 506               (cond ((eq direction :input) :error)
 507                     ((and output
 508                           (member if-exists '(:overwrite :append)))
 509                      :error)
 510                     ((eq direction :probe)
 511                      nil)
 512                     (t
 513                      :create))))
 514       (if (eq if-does-not-exist :create)
 515           (setf mask (logior mask sb-unix:o_creat)))
 516
 517       (let ((original (if (member if-exists
 518                                   '(:rename :rename-and-delete))
 519                           (sb-impl::pick-backup-name name)
 520                           nil))
 521             (delete-original (eq if-exists :rename-and-delete))
 522             (mode #o666))
 523         (when original
 524           ;; We are doing a :rename or :rename-and-delete.
 525           ;; Determine if the file already exists, make sure the original
 526           ;; file is not a directory and keep the mode
 527           (let ((exists
 528                  (and name
 529                       (multiple-value-bind
 530                             (okay err/dev inode orig-mode)
 531                           (sb-unix:unix-stat name)
 532                         (declare (ignore inode)
 533                                  (type (or sb-int:index null) orig-mode))
 534                         (cond
 535                           (okay
 536                            (when (and output (= (logand orig-mode #o170000)
 537                                                 #o40000))
 538                              (error 'sb-int:simple-file-error
 539                                  :pathname pathname
 540                                  :format-control
 541                                  "Cannot open ~S for output: Is a directory."
 542                                  :format-arguments (list name)))
 543                            (setf mode (logand orig-mode #o777))
 544                            t)
 545                           ((eql err/dev sb-unix:enoent)
 546                            nil)
 547                           (t
 548                            (error 'sb-int:simple-file-error
 549                                   :pathname pathname
 550                                   :format-control "Cannot find ~S: ~A"
 551                                   :format-arguments
 552                                     (list name
 553                                       (sb-int:strerror err/dev)))))))))
 554             (unless (and exists
 555                          (rename-file name original))
 556               (setf original nil)
 557               (setf delete-original nil)
 558               ;; In order to use SUPERSEDE instead, we have
 559               ;; to make sure unix:o_creat corresponds to
 560               ;; if-does-not-exist.  unix:o_creat was set
 561               ;; before because of if-exists being :rename.
 562               (unless (eq if-does-not-exist :create)
 563                 (setf mask (logior (logandc2 mask sb-unix:o_creat)
 564                                    sb-unix:o_trunc)))
 565               (setf if-exists :supersede))))
 566
 567         ;; Okay, now we can try the actual open.
 568         (loop
 569           (multiple-value-bind (fd errno)
 570               (if name
 571                   (sb-unix:unix-open name mask mode)
 572                   (values nil #-win32 sb-unix:enoent
 573                               #+win32 sb-win32::error_file_not_found))
 574             (cond ((integerp fd)
 575                    (when (eql if-exists :append)
 576                      (sb-unix:unix-lseek fd 0 sb-unix:l_xtnd))
 577                    (return (values fd name original delete-original)))
 578                   ((eql errno #-win32 sb-unix:enoent
 579                               #+win32 sb-win32::error_file_not_found)
 580                    (case if-does-not-exist
 581                      (:error
 582                       (cerror "Return NIL."
 583                               'sb-int:simple-file-error
 584                               :pathname pathname
 585                               :format-control "Error opening ~S, ~A."
 586                               :format-arguments
 587                               (list pathname
 588                                     (sb-int:strerror errno))))
 589                      (:create
 590                       (cerror "Return NIL."
 591                               'sb-int:simple-file-error
 592                               :pathname pathname
 593                               :format-control
 594                               "Error creating ~S, path does not exist."
 595                               :format-arguments (list pathname))))
 596                    (return nil))
 597                   ((eql errno #-win32 sb-unix:eexist
 598                               #+win32 sb-win32::error_file_not_found)
 599                    (unless (eq nil if-exists)
 600                      (cerror "Return NIL."
 601                              'sb-int:simple-file-error
 602                              :pathname pathname
 603                              :format-control "Error opening ~S, ~A."
 604                              :format-arguments
 605                              (list pathname
 606                                    (sb-int:strerror errno))))
 607                    (return nil))
 608                   #+nil ; FIXME: reinstate this; error reporting is nice.
 609                   ((eql errno sb-unix:eacces)
 610                    (cerror "Try again."
 611                            'sb-int:simple-file-error
 612                            :pathname pathname
 613                            :format-control "Error opening ~S, ~A."
 614                            :format-arguments
 615                            (list pathname
 616                                  (sb-int:strerror errno))))
 617                   (t
 618                    (cerror "Return NIL."
 619                            'sb-int:simple-file-error
 620                            :pathname pathname
 621                            :format-control "Error opening ~S, ~A."
 622                            :format-arguments
 623                            (list pathname
 624                                  (sb-int:strerror errno)))
 625                    (return nil)))))))))
 626
 627 (defun open-fd-stream (pathname &key (class 'sb-sys:fd-stream)
 628                                 (direction :input)
 629                                 (element-type 'base-char)
 630                                 (if-exists nil if-exists-given)
 631                                 (if-does-not-exist nil if-does-not-exist-given)
 632                                 (external-format :default))
 633   (declare (type (or pathname string stream) pathname)
 634            (type (member :input :output :io :probe) direction)
 635            (type (member :error :new-version :rename :rename-and-delete
 636                          :overwrite :append :supersede nil) if-exists)
 637            (type (member :error :create nil) if-does-not-exist))
 638   (let ((filespec (merge-pathnames pathname)))
 639     (multiple-value-bind (fd namestring original delete-original)
 640         (%fd-open filespec direction if-exists if-exists-given
 641                   if-does-not-exist if-does-not-exist-given)
 642       (when fd
 643         (case direction
 644           ((:input :output :io)
 645            (sb-sys:make-fd-stream fd
 646                                   :class class
 647                                   :input (member direction '(:input :io))
 648                                   :output (member direction '(:output :io))
 649                                   :element-type element-type
 650                                   :file namestring
 651                                   :original original
 652                                   :delete-original delete-original
 653                                   :pathname pathname
 654                                   :dual-channel-p nil
 655                                   :input-buffer-p t
 656                                   :auto-close t
 657                                   :external-format external-format))
 658           (:probe
 659            (let ((stream (sb-impl::%make-fd-stream :name namestring :fd fd
 660                                                    :pathname pathname
 661                                                    :element-type element-type)))
 662              (close stream)
 663              stream)))))))
 664
 665
 666 ;; Experimental "filespec" stuff
 667
 668 ;; sat: Hooks to parse URIs etc apparently go here
 669
 670 (defstruct (filespec-parser
 671              (:constructor make-filespec-parser (name priority function)))
 672   name
 673   priority
 674   function)
 675
 676 (defvar *filespec-parsers* ())
 677
 678 (defun add-filespec (name priority function)
 679   (let ((filespec (make-filespec-parser name priority function)))
 680     (setf *filespec-parsers*
 681           (stable-sort (cons filespec (delete name *filespec-parsers*
 682                                               :key #'filespec-parser-name))
 683                        #'>
 684                        :key #'filespec-parser-priority)))
 685   t)
 686
 687 (defmacro define-filespec (name lambda-list &body body)
 688   (let ((truename (if (consp name) (first name) name))
 689         (priority (if (consp name) (second name) 0)))
 690     `(add-filespec ',truename ,priority (lambda ,lambda-list
 691                                           (block ,truename
 692                                             ,@body)))))
 693
 694 (defun parse-filespec (string &optional (errorp t))
 695   (dolist (i *filespec-parsers* (when errorp
 696                                   (error "~S not recognised." string)))
 697     (let ((result (ignore-errors
 698                     (funcall (filespec-parser-function i) string))))
 699       (when result (return result)))))
 700
 701 (define-filespec pathname (string)
 702   (pathname string))