X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Funix.lisp;h=b1193bf7fec735e4260ac7ec50590293d4797e7d;hb=97e52e46f9bcb054eec35a9c326db75993441ca1;hp=16efdaf9719f103c1c5c8a417f78b634a6016811;hpb=d45e8a2e9167150c8283783152d2449bd8d59d2d;p=sbcl.git diff --git a/src/code/unix.lisp b/src/code/unix.lisp index 16efdaf..b1193bf 100644 --- a/src/code/unix.lisp +++ b/src/code/unix.lisp @@ -90,9 +90,9 @@ ;;;; 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." +(define-alien-routine ("getenv" posix-getenv) c-string + "Return the \"value\" part of the environment string \"name=value\" which + corresponds to NAME, or NIL if there is none." (name c-string)) ;;; from stdio.h @@ -112,12 +112,12 @@ ;;; 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) +(define-alien-type fd-mask unsigned-long) (eval-when (:compile-toplevel :load-toplevel :execute) (defconstant fd-setsize 1024)) -(def-alien-type nil +(define-alien-type nil (struct fd-set (fds-bits (array fd-mask #.(/ fd-setsize 32))))) @@ -152,7 +152,7 @@ ;; A time value that is accurate to the nearest ;; microsecond but also has a range of years. -(def-alien-type nil +(define-alien-type nil (struct timeval (tv-sec time-t) ; seconds (tv-usec time-t))) ; and microseconds @@ -163,7 +163,7 @@ (defconstant rusage_children -1) ; terminated child processes (defconstant rusage_both -2) -(def-alien-type nil +(define-alien-type nil (struct rusage (ru-utime (struct timeval)) ; user time used (ru-stime (struct timeval)) ; system time used. @@ -264,6 +264,16 @@ (type unix-file-mode mode)) (void-syscall ("mkdir" c-string int) name mode)) +;;; Given a C char* pointer allocated by malloc(), free it and return a +;;; corresponding Lisp string (or return NIL if the pointer is a C NULL). +(defun newcharstar-string (newcharstar) + (declare (type (alien (* char)) newcharstar)) + (if (null-alien newcharstar) + nil + (prog1 + (cast newcharstar c-string) + (free-alien newcharstar)))) + ;;; Return the Unix current directory as a SIMPLE-STRING, in the ;;; style returned by getcwd() (no trailing slash character). (defun posix-getcwd () @@ -271,16 +281,24 @@ ;; 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))))) + ;; + ;; SunOS and OSF/1 provide almost as useful an extension: if given a null + ;; buffer pointer, it will automatically allocate size space. The + ;; KLUDGE in this solution arises because we have just read off + ;; PATH_MAX+1 from the Solaris header files and stuck it in here as + ;; a constant. Going the grovel_headers route doesn't seem to be + ;; helpful, either, as Solaris doesn't export PATH_MAX from + ;; unistd.h. + #!-(or linux openbsd freebsd sunos osf1) (,stub,) + #!+(or linux openbsd freebsd sunos osf1) + (or (newcharstar-string (alien-funcall (extern-alien "getcwd" + (function (* char) + (* char) + size-t)) + nil + #!+(or linux openbsd freebsd) 0 + #!+(or sunos osf1) 1025)) + (simple-perror "getcwd"))) ;;; Return the Unix current directory as a SIMPLE-STRING terminated ;;; by a slash character. @@ -318,25 +336,42 @@ (void-syscall ("exit" int) code)) ;;; Return the process id of the current process. -(def-alien-routine ("getpid" unix-getpid) int) - -;;; 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. +(define-alien-routine ("getpid" unix-getpid) int) + +;;; Return the real user id associated with the current process. +(define-alien-routine ("getuid" unix-getuid) int) + +;;; Translate a user id into a login name. +(defun uid-username (uid) + (or (newcharstar-string (alien-funcall (extern-alien "uid_username" + (function (* char) int)) + uid)) + (error "found no match for Unix uid=~S" uid))) + +;;; Return the namestring of the home directory, being careful to +;;; include a trailing #\/ +(defun uid-homedir (uid) + (or (newcharstar-string (alien-funcall (extern-alien "uid_homedir" + (function (* char) int)) + uid)) + (error "failed to resolve home directory for Unix uid=~S" uid))) + +;;; 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. @@ -344,26 +379,6 @@ (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))) @@ -390,8 +405,9 @@ ;;; FIXME: All we seem to need is the RUSAGE_SELF version of this. ;;; -;;; Like getrusage(2), but return only the system and user time, -;;; and return the seconds and microseconds as separate values. +;;; This is like getrusage(2), except it returns only the system and +;;; user time, and returns the seconds and microseconds as separate +;;; values. #!-sb-fluid (declaim (inline unix-fast-getrusage)) (defun unix-fast-getrusage (who) (declare (values (member t) @@ -437,30 +453,29 @@ ;;;; sys/select.h -(defmacro unix-fast-select (num-descriptors - read-fds write-fds exception-fds - timeout-secs &optional (timeout-usecs 0)) - #!+sb-doc - "Perform the UNIX select(2) system call." - (declare (type (integer 0 #.FD-SETSIZE) num-descriptors) +;;;; FIXME: Why have both UNIX-SELECT and UNIX-FAST-SELECT? + +;;; Perform the UNIX select(2) system call. +(declaim (inline unix-fast-select)) ; (used to be a macro in CMU CL) +(defun unix-fast-select (num-descriptors + read-fds write-fds exception-fds + timeout-secs &optional (timeout-usecs 0)) + (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 - ;; be in a declaration inside the LET expansion, not in the - ;; macro compile-time code. - `(let ((timeout-secs ,timeout-secs)) - (with-alien ((tv (struct timeval))) - (when timeout-secs - (setf (slot tv 'tv-sec) timeout-secs) - (setf (slot tv 'tv-usec) ,timeout-usecs)) - (int-syscall ("select" int (* (struct fd-set)) (* (struct fd-set)) - (* (struct fd-set)) (* (struct timeval))) - ,num-descriptors ,read-fds ,write-fds ,exception-fds - (if timeout-secs (alien-sap (addr tv)) (int-sap 0)))))) + ;; (declare (optimize (speed 3) (safety 0) (inhibit-warnings 3))) + ;; here. Is that important for SBCL? If so, why? Profiling might tell us.. + (with-alien ((tv (struct timeval))) + (when timeout-secs + (setf (slot tv 'tv-sec) timeout-secs) + (setf (slot tv 'tv-usec) timeout-usecs)) + (int-syscall ("select" int (* (struct fd-set)) (* (struct fd-set)) + (* (struct fd-set)) (* (struct timeval))) + num-descriptors read-fds write-fds exception-fds + (if timeout-secs (alien-sap (addr tv)) (int-sap 0))))) ;;; UNIX-SELECT accepts sets of file descriptors and waits for an event ;;; to happen on one of them or to time out. @@ -531,7 +546,7 @@ ;;; st_size is a long, not an off-t, because off-t is a 64-bit ;;; quantity on Alpha. And FIXME: "No one would want a file length ;;; longer than 32 bits anyway, right?":-| -(def-alien-type nil +(define-alien-type nil (struct wrapped_stat (st-dev unsigned-long) ; would be dev-t in a real stat (st-ino ino-t) @@ -606,13 +621,13 @@ ;; the POSIX.4 structure for a time value. This is like a "struct ;; timeval" but has nanoseconds instead of microseconds. -(def-alien-type nil +(define-alien-type nil (struct timespec (tv-sec long) ; seconds (tv-nsec long))) ; nanoseconds ;; used by other time functions -(def-alien-type nil +(define-alien-type nil (struct tm (tm-sec int) ; Seconds. [0-60] (1 leap second) (tm-min int) ; Minutes. [0-59] @@ -626,9 +641,9 @@ (tm-gmtoff long) ; Seconds east of UTC. (tm-zone c-string))) ; Timezone abbreviation. -(def-alien-routine get-timezone sb!c-call:void - (when sb!c-call:long :in) - (minutes-west sb!c-call:int :out) +(define-alien-routine get-timezone sb!alien:void + (when sb!alien:long :in) + (minutes-west sb!alien:int :out) (daylight-savings-p sb!alien:boolean :out)) (defun unix-get-minutes-west (secs) @@ -646,7 +661,7 @@ ;;; Structure crudely representing a timezone. KLUDGE: This is ;;; obsolete and should never be used. -(def-alien-type nil +(define-alien-type nil (struct timezone (tz-minuteswest int) ; minutes west of Greenwich (tz-dsttime int))) ; type of dst correction @@ -701,87 +716,71 @@ ((eql kind s-iflnk) :link) (t :special)))))) -;;; 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 - "~@" - :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))) + (/noshow "entering UNIX-RESOLVE-LINKS") + (loop with previous-pathnames = nil do + (/noshow pathname previous-pathnames) + (let ((link (unix-readlink pathname))) + (/noshow 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))) + (/noshow 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 #\.) @@ -791,12 +790,12 @@ ((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 .. @@ -824,7 +823,7 @@ (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)) @@ -856,6 +855,17 @@ (t (subseq dst 0 dst-len))))) +;;;; A magic constant for wait3(). +;;;; +;;;; FIXME: This used to be defined in run-program.lisp as +;;;; (defconstant wait-wstopped #-svr4 #o177 #+svr4 wait-wuntraced) +;;;; According to some of the man pages, the #o177 is part of the API +;;;; for wait3(); that said, under SunOS there is a WSTOPPED thing in +;;;; the headers that may or may not be the same thing. To be +;;;; investigated. -- CSR, 2002-03-25 +(defconstant wstopped #o177) + + ;;;; stuff not yet found in the header files ;;;; ;;;; Abandon all hope who enters here...