;;;; hacking the Unix environment
(def-alien-routine ("getenv" posix-getenv) c-string
- "Return the environment string \"name=value\" which corresponds to NAME, or
- NIL if there is none."
+ "Return the \"value\" part of the environment string \"name=value\" which
+ corresponds to NAME, or NIL if there is none."
(name c-string))
\f
;;; from stdio.h
(/show0 "unix.lisp 220")
-;;; FIXME: Isn't there some way to use a C wrapper to avoid this hand-copying?
-(defconstant +max-s-long+ 2147483647)
-(defconstant +max-u-long+ 4294967295)
-(def-alien-type quad-t #+nil long-long #-nil (array long 2))
-(def-alien-type uquad-t #+nil unsigned-long-long
- #-nil (array unsigned-long 2))
-(def-alien-type qaddr-t (* quad-t))
-(def-alien-type daddr-t int)
-(def-alien-type caddr-t (* char))
-(def-alien-type swblk-t long)
-(def-alien-type size-t unsigned-int)
-(def-alien-type ssize-t int)
-
-;;; FIXME: We shouldn't hand-copy types from header files into Lisp like this
-;;; unless we have extreme provocation. Reading directories is not extreme
-;;; enough, since it doesn't need to be blindingly fast: we can just implement
-;;; those functions in C as a wrapper layer.
+;;; FIXME: We shouldn't hand-copy types from header files into Lisp
+;;; like this unless we have extreme provocation. Reading directories
+;;; is not extreme enough, since it doesn't need to be blindingly
+;;; fast: we can just implement those functions in C as a wrapper
+;;; layer.
(def-alien-type fd-mask unsigned-long)
(eval-when (:compile-toplevel :load-toplevel :execute)
(values (deref fds 0) (deref fds 1))
(cast fds (* int)))))
-;;; UNIX-CHDIR accepts a directory name and makes that the
-;;; current working directory.
-(defun unix-chdir (path)
- (declare (type unix-pathname path))
- (void-syscall ("chdir" c-string) path))
-
(defun unix-mkdir (name mode)
(declare (type unix-pathname name)
(type unix-file-mode mode))
(void-syscall ("mkdir" c-string int) name mode))
-;;; Return the current directory as a SIMPLE-STRING.
-(defun unix-current-directory ()
- ;; FIXME: Gcc justifiably complains that getwd is dangerous and should
- ;; not be used; especially with a hardwired 1024 buffer size, yecch.
- ;; This should be rewritten to use getcwd(3), perhaps by writing
- ;; a C service routine to do the actual call to getcwd(3) and check
- ;; of return values.
- (with-alien ((buf (array char 1024)))
- (values (not (zerop (alien-funcall (extern-alien "getwd"
- (function int (* char)))
- (cast buf (* char)))))
- (cast buf c-string))))
+;;; Return the Unix current directory as a SIMPLE-STRING, in the
+;;; style returned by getcwd() (no trailing slash character).
+(defun posix-getcwd ()
+ ;; This implementation relies on a BSD/Linux extension to getcwd()
+ ;; behavior, automatically allocating memory when a null buffer
+ ;; pointer is used. On a system which doesn't support that
+ ;; extension, it'll have to be rewritten somehow.
+ #!-(or linux openbsd freebsd) (,stub,)
+ (let* ((raw-char-ptr (alien-funcall (extern-alien "getcwd"
+ (function (* char)
+ (* char) size-t))
+ nil 0)))
+ (if (null-alien raw-char-ptr)
+ (simple-perror "getcwd")
+ (prog1
+ (cast raw-char-ptr c-string)
+ (free-alien raw-char-ptr)))))
+
+;;; Return the Unix current directory as a SIMPLE-STRING terminated
+;;; by a slash character.
+(defun posix-getcwd/ ()
+ (concatenate 'string (posix-getcwd) "/"))
+
+;;; Convert at the UNIX level from a possibly relative filename to
+;;; an absolute filename.
+;;;
+;;; FIXME: Do we still need this even as we switch to
+;;; *DEFAULT-PATHNAME-DEFAULTS*? I think maybe we do, since it seems
+;;; to be valid for the user to set *DEFAULT-PATHNAME-DEFAULTS* to
+;;; have a NIL directory component, and then this'd be the only way to
+;;; interpret a relative directory specification. But I don't find the
+;;; ANSI pathname documentation to be a model of clarity. Maybe
+;;; someone who understands it better can take a look at this.. -- WHN
+(defun unix-maybe-prepend-current-directory (name)
+ (declare (simple-string name))
+ (if (and (> (length name) 0) (char= (schar name 0) #\/))
+ name
+ (concatenate 'simple-string (posix-getcwd/) name)))
;;; Duplicate an existing file descriptor (given as the argument) and
;;; return it. If FD is not a valid file descriptor, NIL and an error
;;; Return the real user-id associated with the current process.
(def-alien-routine ("getuid" unix-getuid) int)
-;;; Invoke readlink(2) on the file name specified by the simple string
-;;; PATH. Return up to two values: the contents of the symbolic link
-;;; if the call is successful, or NIL and the Unix error number.
+;;; Invoke readlink(2) on the file name specified by PATH. Return
+;;; (VALUES LINKSTRING NIL) on success, or (VALUES NIL ERRNO) on
+;;; failure.
(defun unix-readlink (path)
(declare (type unix-pathname path))
- (with-alien ((buf (array char 1024)))
- (syscall ("readlink" c-string (* char) int)
- (let ((string (make-string result)))
- (sb!kernel:copy-from-system-area
- (alien-sap buf) 0
- string (* sb!vm:vector-data-offset sb!vm:word-bits)
- (* result sb!vm:byte-bits))
- string)
- path (cast buf (* char)) 1024)))
+ (with-alien ((ptr (* char)
+ (alien-funcall (extern-alien
+ "wrapped_readlink"
+ (function (* char) c-string))
+ path)))
+ (if (null-alien ptr)
+ (values nil (get-errno))
+ (multiple-value-prog1
+ (values (with-alien ((c-string c-string ptr)) c-string)
+ nil)
+ (free-alien ptr)))))
;;; UNIX-UNLINK accepts a name and deletes the directory entry for that
;;; name and the file if this is the last link.
(declare (type unix-pathname name))
(void-syscall ("unlink" c-string) name))
-;;; Set the tty-process-group for the unix file-descriptor FD to PGRP.
-;;; If not supplied, FD defaults to "/dev/tty".
-(defun %set-tty-process-group (pgrp &optional fd)
- (let ((old-sigs (unix-sigblock (sigmask :sigttou
- :sigttin
- :sigtstp
- :sigchld))))
- (declare (type (unsigned-byte 32) old-sigs))
- (unwind-protect
- (if fd
- (tcsetpgrp fd pgrp)
- (multiple-value-bind (tty-fd errno) (unix-open "/dev/tty" o_rdwr 0)
- (cond (tty-fd
- (multiple-value-prog1
- (tcsetpgrp tty-fd pgrp)
- (unix-close tty-fd)))
- (t
- (values nil errno)))))
- (unix-sigsetmask old-sigs))))
-
;;; Return the name of the host machine as a string.
(defun unix-gethostname ()
(with-alien ((buf (array char 256)))
#!-sb-fluid (declaim (inline unix-fast-getrusage))
(defun unix-fast-getrusage (who)
(declare (values (member t)
- (unsigned-byte 31) (mod 1000000)
- (unsigned-byte 31) (mod 1000000)))
+ (unsigned-byte 31) (integer 0 1000000)
+ (unsigned-byte 31) (integer 0 1000000)))
(with-alien ((usage (struct rusage)))
(syscall* ("getrusage" int (* (struct rusage)))
(values t
timeout-secs &optional (timeout-usecs 0))
#!+sb-doc
"Perform the UNIX select(2) system call."
- (declare (type (integer 0 #.FD-SETSIZE) num-descriptors)
+ ;; FIXME: These DECLAREs don't belong at macroexpansion time. They
+ ;; should be done at runtime instead. Perhaps we could just redo
+ ;; UNIX-FAST-SELECT as an inline function, and then all the
+ ;; declarations would work nicely.
+ #|
+ (declare (type (integer 0 #.fd-setsize) num-descriptors)
(type (or (alien (* (struct fd-set))) null)
read-fds write-fds exception-fds)
(type (or null (unsigned-byte 31)) timeout-secs)
- (type (unsigned-byte 31) timeout-usecs) )
+ (type (unsigned-byte 31) timeout-usecs))
+ |#
;; FIXME: CMU CL had
;; (optimize (speed 3) (safety 0) (inhibit-warnings 3))
;; in the declarations above. If they're important, they should
((eql kind s-iflnk) :link)
(t :special))))))
-(defun unix-maybe-prepend-current-directory (name)
- (declare (simple-string name))
- (if (and (> (length name) 0) (char= (schar name 0) #\/))
- name
- (multiple-value-bind (win dir) (unix-current-directory)
- (if win
- (concatenate 'simple-string dir "/" name)
- name))))
-
-;;; Return the pathname with all symbolic links resolved.
-;;;
-;;; FIXME: Could we just use Unix readlink(2) instead?
+;;; Is the Unix pathname PATHNAME relative, instead of absolute? (E.g.
+;;; "passwd" or "etc/passwd" instead of "/etc/passwd"?)
+(defun relative-unix-pathname? (pathname)
+ (declare (type simple-string pathname))
+ (or (zerop (length pathname))
+ (char/= (schar pathname 0) #\/)))
+
+;;; Return PATHNAME with all symbolic links resolved. PATHNAME should
+;;; already be a complete absolute Unix pathname, since at least in
+;;; sbcl-0.6.12.36 we're called only from TRUENAME, and only after
+;;; paths have been converted to absolute paths, so we don't need to
+;;; try to handle any more generality than that.
(defun unix-resolve-links (pathname)
- (declare (simple-string pathname))
- (let ((len (length pathname))
- (pending pathname))
- (declare (fixnum len) (simple-string pending))
- (if (zerop len)
- pathname
- (let ((result (make-string 1024 :initial-element (code-char 0)))
- (fill-ptr 0)
- (name-start 0))
- (loop
- (let* ((name-end (or (position #\/ pending :start name-start) len))
- (new-fill-ptr (+ fill-ptr (- name-end name-start))))
- (replace result pending
- :start1 fill-ptr
- :end1 new-fill-ptr
- :start2 name-start
- :end2 name-end)
- (let ((kind (unix-file-kind (if (zerop name-end) "/" result) t)))
- (unless kind (return nil))
- (cond ((eq kind :link)
- (multiple-value-bind (link err) (unix-readlink result)
- (unless link
- (error 'simple-file-error
- :pathname pathname
- :format-control
- "~@<error reading link ~S: ~2I~_~A~:>"
- :format-arguments (list (subseq
- result 0 fill-ptr)
- (strerror err))))
- (cond ((or (zerop (length link))
- (char/= (schar link 0) #\/))
- ;; It's a relative link.
- (fill result (code-char 0)
- :start fill-ptr
- :end new-fill-ptr))
- ((string= result "/../" :end1 4)
- ;; It's across the super-root.
- (let ((slash (or (position #\/ result :start 4)
- 0)))
- (fill result (code-char 0)
- :start slash
- :end new-fill-ptr)
- (setf fill-ptr slash)))
- (t
- ;; It's absolute.
- (and (> (length link) 0)
- (char= (schar link 0) #\/))
- (fill result (code-char 0) :end new-fill-ptr)
- (setf fill-ptr 0)))
- (setf pending
- (if (= name-end len)
- link
- (concatenate 'simple-string
- link
- (subseq pending name-end))))
- (setf len (length pending))
- (setf name-start 0)))
- ((= name-end len)
- (return (subseq result 0 new-fill-ptr)))
- ((eq kind :directory)
- (setf (schar result new-fill-ptr) #\/)
- (setf fill-ptr (1+ new-fill-ptr))
- (setf name-start (1+ name-end)))
- (t
- (return nil))))))))))
+ (declare (type simple-string pathname))
+ (aver (not (relative-unix-pathname? pathname)))
+ (/show "entering UNIX-RESOLVE-LINKS")
+ (loop with previous-pathnames = nil do
+ (/show pathname previous-pathnames)
+ (let ((link (unix-readlink pathname)))
+ (/show link)
+ ;; Unlike the old CMU CL code, we handle a broken symlink by
+ ;; returning the link itself. That way, CL:TRUENAME on a
+ ;; broken link returns the link itself, so that CL:DIRECTORY
+ ;; can return broken links, so that even without
+ ;; Unix-specific extensions to do interesting things with
+ ;; them, at least Lisp programs can see them and, if
+ ;; necessary, delete them. (This is handy e.g. when your
+ ;; managed-by-Lisp directories are visited by Emacs, which
+ ;; creates broken links as notes to itself.)
+ (if (null link)
+ (return pathname)
+ (let ((new-pathname
+ (unix-simplify-pathname
+ (if (relative-unix-pathname? link)
+ (let* ((dir-len (1+ (position #\/
+ pathname
+ :from-end t)))
+ (dir (subseq pathname 0 dir-len)))
+ (/show dir)
+ (concatenate 'string dir link))
+ link))))
+ (if (unix-file-kind new-pathname)
+ (setf pathname new-pathname)
+ (return pathname)))))
+ ;; To generalize the principle that even if portable Lisp code
+ ;; can't do anything interesting with a broken symlink, at
+ ;; least it should be able to see and delete it, when we
+ ;; detect a cyclic link, we return the link itself. (So even
+ ;; though portable Lisp code can't do anything interesting
+ ;; with a cyclic link, at least it can see it and delete it.)
+ (if (member pathname previous-pathnames :test #'string=)
+ (return pathname)
+ (push pathname previous-pathnames))))
(defun unix-simplify-pathname (src)
- (declare (simple-string src))
+ (declare (type simple-string src))
(let* ((src-len (length src))
(dst (make-string src-len))
(dst-len 0)
(dots 0)
(last-slash nil))
(macrolet ((deposit (char)
- `(progn
- (setf (schar dst dst-len) ,char)
- (incf dst-len))))
+ `(progn
+ (setf (schar dst dst-len) ,char)
+ (incf dst-len))))
(dotimes (src-index src-len)
(let ((char (schar src src-index)))
(cond ((char= char #\.)
((char= char #\/)
(case dots
(0
- ;; Either ``/...' or ``...//...'
+ ;; either ``/...' or ``...//...'
(unless last-slash
(setf last-slash dst-len)
(deposit char)))
(1
- ;; Either ``./...'' or ``..././...''
+ ;; either ``./...'' or ``..././...''
(decf dst-len))
(2
;; We've found ..
(setf last-slash dst-len)
(deposit char))))
(t
- ;; Something other than a dot between slashes.
+ ;; something other than a dot between slashes
(setf last-slash dst-len)
(deposit char)))
(setf dots 0))
projects / sbcl.git / blobdiff