;;;; pathname parsing for Win32 filesystems ;;;; This software is part of the SBCL system. See the README file for ;;;; more information. ;;;; ;;;; This software is derived from the CMU CL system, which was ;;;; written at Carnegie Mellon University and released into the ;;;; public domain. The software is in the public domain and is ;;;; provided with absolutely no warranty. See the COPYING and CREDITS ;;;; files for more information. (in-package "SB!IMPL") (defun extract-device (namestr start end) (declare (type simple-string namestr) (type index start end)) (if (>= end (+ start 2)) (let ((c0 (char namestr start)) (c1 (char namestr (1+ start)))) (cond ((and (eql c1 #\:) (alpha-char-p c0)) ;; "X:" style, saved as X (values (string (char namestr start)) (+ start 2))) ((and (member c0 '(#\/ #\\)) (eql c0 c1) (>= end (+ start 3))) ;; "//UNC" style, saved as UNC ;; FIXME: at unparsing time we tell these apart by length, ;; which seems a bit lossy -- presumably one-letter UNC ;; hosts can exist as well. That seems a less troublesome ;; restriction than disallowing UNC hosts whose names match ;; logical pathname hosts... Time will tell -- both LispWorks ;; and ACL use the host component for UNC hosts, so maybe ;; we will end up there as well. (let ((p (or (position c0 namestr :start (+ start 3) :end end) end))) (values (subseq namestr (+ start 2) p) p))) (t (values nil start)))) (values nil start))) (defun split-at-slashes-and-backslashes (namestr start end) (declare (type simple-string namestr) (type index start end)) ;; FIXME: There is a fundamental brokenness in using the same ;; character as escape character and directory separator in ;; non-native pathnames. (PATHNAME-DIRECTORY #P"\\*/") should ;; probably be (:RELATIVE "*") everywhere, but on Windows it's ;; (:ABSOLUTE :WILD)! See lp#673625. (let ((absolute (and (/= start end) (or (char= (schar namestr start) #\/) (char= (schar namestr start) #\\))))) (when absolute (incf start)) ;; Next, split the remainder into slash-separated chunks. (collect ((pieces)) (loop (let ((slash (position-if (lambda (c) (or (char= c #\/) (char= c #\\))) namestr :start start :end end))) (pieces (cons start (or slash end))) (unless slash (return)) (setf start (1+ slash)))) (values absolute (pieces))))) (defun parse-win32-namestring (namestring start end) (declare (type simple-string namestring) (type index start end)) (setf namestring (coerce namestring 'simple-string)) (multiple-value-bind (device new-start) (extract-device namestring start end) (multiple-value-bind (absolute pieces) (split-at-slashes-and-backslashes namestring new-start end) (multiple-value-bind (name type version) (let* ((tail (car (last pieces))) (tail-start (car tail)) (tail-end (cdr tail))) (unless (= tail-start tail-end) (setf pieces (butlast pieces)) (extract-name-type-and-version namestring tail-start tail-end))) (when (stringp name) (let ((position (position-if (lambda (char) (or (char= char (code-char 0)) (char= char #\/))) name))) (when position (error 'namestring-parse-error :complaint "can't embed #\\Nul or #\\/ in Windows namestring" :namestring namestring :offset position)))) (let (home) ;; Deal with ~ and ~user. (when (car pieces) (destructuring-bind (start . end) (car pieces) (when (and (not absolute) (not (eql start end)) (string= namestring "~" :start1 start :end1 (1+ start))) (setf absolute t) (if (> end (1+ start)) (setf home (list :home (subseq namestring (1+ start) end))) (setf home :home)) (pop pieces)))) ;; Now we have everything we want. So return it. (values nil ; no host for Win32 namestrings device (collect ((dirs)) (dolist (piece pieces) (let ((piece-start (car piece)) (piece-end (cdr piece))) (unless (= piece-start piece-end) (cond ((string= namestring ".." :start1 piece-start :end1 piece-end) (dirs :up)) ((string= namestring "**" :start1 piece-start :end1 piece-end) (dirs :wild-inferiors)) (t (dirs (maybe-make-pattern namestring piece-start piece-end))))))) (cond (absolute (if home (list* :absolute home (dirs)) (cons :absolute (dirs)))) ((dirs) (cons :relative (dirs))) (t nil))) name type version)))))) (defun parse-native-win32-namestring (namestring start end as-directory) (declare (type simple-string namestring) (type index start end)) (setf namestring (coerce namestring 'simple-string)) (multiple-value-bind (device new-start) (extract-device namestring start end) (multiple-value-bind (absolute ranges) (split-at-slashes-and-backslashes namestring new-start end) (let* ((components (loop for ((start . end) . rest) on ranges for piece = (subseq namestring start end) collect (if (and (string= piece "..") rest) :up piece))) (directory (if (and as-directory (string/= "" (car (last components)))) components (butlast components))) (name-and-type (unless as-directory (let* ((end (first (last components))) (dot (position #\. end :from-end t))) ;; FIXME: can we get this dot-interpretation knowledge ;; from existing code? EXTRACT-NAME-TYPE-AND-VERSION ;; does slightly more work than that. (cond ((string= end "") (list nil nil)) ((and dot (> dot 0)) (list (subseq end 0 dot) (subseq end (1+ dot)))) (t (list end nil))))))) (values nil device (cons (if absolute :absolute :relative) directory) (first name-and-type) (second name-and-type) nil))))) (defun unparse-win32-host (pathname) (declare (type pathname pathname) (ignore pathname)) ;; FIXME: same as UNPARSE-UNIX-HOST. That's probably not good. "") (defun unparse-win32-device (pathname &optional native) (declare (type pathname pathname)) (let ((device (pathname-device pathname)) (directory (pathname-directory pathname))) (cond ((or (null device) (eq device :unspecific)) "") ((and (= 1 (length device)) (alpha-char-p (char device 0))) (concatenate 'simple-string device ":")) ((and (consp directory) (eq :relative (car directory))) (error "No printed representation for a relative UNC pathname.")) (t (if native (concatenate 'simple-string "\\\\" device) (concatenate 'simple-string "//" device)))))) (defun unparse-win32-file (pathname) (declare (type pathname pathname)) (collect ((strings)) (let* ((name (%pathname-name pathname)) (type (%pathname-type pathname)) (type-supplied (not (or (null type) (eq type :unspecific))))) ;; Note: by ANSI 19.3.1.1.5, we ignore the version slot when ;; translating logical pathnames to a filesystem without ;; versions (like Win32). (when name (when (and (null type) (typep name 'string) (> (length name) 0) (position #\. name :start 1)) (error "too many dots in the name: ~S" pathname)) (when (and (typep name 'string) (string= name "")) (error "name is of length 0: ~S" pathname)) (strings (unparse-physical-piece name))) (when type-supplied (unless name (error "cannot specify the type without a file: ~S" pathname)) (when (typep type 'simple-string) (when (position #\. type) (error "type component can't have a #\. inside: ~S" pathname))) (strings ".") (strings (unparse-physical-piece type)))) (apply #'concatenate 'simple-string (strings)))) (defun unparse-win32-namestring (pathname) (declare (type pathname pathname)) (concatenate 'simple-string (unparse-win32-device pathname) (unparse-physical-directory pathname) (unparse-win32-file pathname))) (defun unparse-native-win32-namestring (pathname as-file) (declare (type pathname pathname)) (let* ((device (pathname-device pathname)) (directory (pathname-directory pathname)) (name (pathname-name pathname)) (name-present-p (typep name '(not (member nil :unspecific)))) (name-string (if name-present-p name "")) (type (pathname-type pathname)) (type-present-p (typep type '(not (member nil :unspecific)))) (type-string (if type-present-p type ""))) (when name-present-p (setf as-file nil)) (coerce (with-output-to-string (s) (when device (write-string (unparse-win32-device pathname t) s)) (when directory (ecase (pop directory) (:absolute (let ((next (pop directory))) (cond ((eq :home next) (write-string (user-homedir-namestring) s)) ((and (consp next) (eq :home (car next))) (let ((where (user-homedir-namestring (second next)))) (if where (write-string where s) (error "User homedir unknown for: ~S" (second next))))) (next (push next directory))) (write-char #\\ s))) (:relative))) (loop for (piece . subdirs) on directory do (typecase piece ((member :up) (write-string ".." s)) (string (write-string piece s)) (t (error "ungood directory segment in NATIVE-NAMESTRING: ~S" piece))) if (or subdirs (stringp name)) do (write-char #\\ s) else do (unless as-file (write-char #\\ s))) (if name-present-p (progn (unless (stringp name-string) ;some kind of wild field (error "ungood name component in NATIVE-NAMESTRING: ~S" name)) (write-string name-string s) (when type-present-p (unless (stringp type-string) ;some kind of wild field (error "ungood type component in NATIVE-NAMESTRING: ~S" type)) (write-char #\. s) (write-string type-string s))) (when type-present-p ; (error "type component without a name component in NATIVE-NAMESTRING: ~S" type)))) 'simple-string))) ;;; FIXME. (defun unparse-win32-enough (pathname defaults) (declare (type pathname pathname defaults)) (flet ((lose () (error "~S cannot be represented relative to ~S." pathname defaults))) (collect ((strings)) (let* ((pathname-directory (%pathname-directory pathname)) (defaults-directory (%pathname-directory defaults)) (prefix-len (length defaults-directory)) (result-directory (cond ((null pathname-directory) '(:relative)) ((eq (car pathname-directory) :relative) pathname-directory) ((and (> prefix-len 0) (>= (length pathname-directory) prefix-len) (compare-component (subseq pathname-directory 0 prefix-len) defaults-directory)) ;; Pathname starts with a prefix of default. So ;; just use a relative directory from then on out. (cons :relative (nthcdr prefix-len pathname-directory))) ((eq (car pathname-directory) :absolute) ;; We are an absolute pathname, so we can just use it. pathname-directory) (t (bug "Bad fallthrough in ~S" 'unparse-unix-enough))))) (strings (unparse-physical-directory-list result-directory))) (let* ((pathname-type (%pathname-type pathname)) (type-needed (and pathname-type (not (eq pathname-type :unspecific)))) (pathname-name (%pathname-name pathname)) (name-needed (or type-needed (and pathname-name (not (compare-component pathname-name (%pathname-name defaults))))))) (when name-needed (unless pathname-name (lose)) (when (and (null pathname-type) (typep pathname-name 'simple-string) (position #\. pathname-name :start 1)) (error "too many dots in the name: ~S" pathname)) (strings (unparse-physical-piece pathname-name))) (when type-needed (when (or (null pathname-type) (eq pathname-type :unspecific)) (lose)) (when (typep pathname-type 'simple-string) (when (position #\. pathname-type) (error "type component can't have a #\. inside: ~S" pathname))) (strings ".") (strings (unparse-physical-piece pathname-type)))) (apply #'concatenate 'simple-string (strings))))) ;; FIXME: This has been converted rather blindly from the Unix ;; version, with no reference to any Windows docs what so ever. (defun simplify-win32-namestring (src) (declare (type simple-string src)) (let* ((src-len (length src)) (dst (make-string src-len :element-type 'character)) (dst-len 0) (dots 0) (last-slash nil)) (flet ((deposit (char) (setf (schar dst dst-len) char) (incf dst-len)) (slashp (char) (find char "\\/"))) (dotimes (src-index src-len) (let ((char (schar src src-index))) (cond ((char= char #\.) (when dots (incf dots)) (deposit char)) ((slashp char) (case dots (0 ;; either ``/...' or ``...//...' (unless last-slash (setf last-slash dst-len) (deposit char))) (1 ;; either ``./...'' or ``..././...'' (decf dst-len)) (2 ;; We've found .. (cond ((and last-slash (not (zerop last-slash))) ;; There is something before this .. (let ((prev-prev-slash (position-if #'slashp dst :end last-slash :from-end t))) (cond ((and (= (+ (or prev-prev-slash 0) 2) last-slash) (char= (schar dst (- last-slash 2)) #\.) (char= (schar dst (1- last-slash)) #\.)) ;; The something before this .. is another .. (deposit char) (setf last-slash dst-len)) (t ;; The something is some directory or other. (setf dst-len (if prev-prev-slash (1+ prev-prev-slash) 0)) (setf last-slash prev-prev-slash))))) (t ;; There is nothing before this .., so we need to keep it (setf last-slash dst-len) (deposit char)))) (t ;; something other than a dot between slashes (setf last-slash dst-len) (deposit char))) (setf dots 0)) (t (setf dots nil) (setf (schar dst dst-len) char) (incf dst-len))))) ;; ...finish off (when (and last-slash (not (zerop last-slash))) (case dots (1 ;; We've got ``foobar/.'' (decf dst-len)) (2 ;; We've got ``foobar/..'' (unless (and (>= last-slash 2) (char= (schar dst (1- last-slash)) #\.) (char= (schar dst (- last-slash 2)) #\.) (or (= last-slash 2) (slashp (schar dst (- last-slash 3))))) (let ((prev-prev-slash (position-if #'slashp dst :end last-slash :from-end t))) (if prev-prev-slash (setf dst-len (1+ prev-prev-slash)) (return-from simplify-win32-namestring (coerce ".\\" 'simple-string))))))))) (cond ((zerop dst-len) ".\\") ((= dst-len src-len) dst) (t (subseq dst 0 dst-len)))))