EFS 1.18 bug: infinite recursion in efs-internal-file-directory-p

Salut bug team: file-symlink-p just returns nil without running its handler(s) and make-symbolic-link doesn't exist at all on systems that don't support symlinks (ie S_IFLNK is undefined) such as MS Windows. This is probably a bug in emacs, and exists in XEmacs 21.0 & 21.2, FSF Emacs 19.34 & 20.34 and probably all other recent versions of XEmacs and FSF Emacs. For reference, I've attached a patch against src/fileio.c in XEmacs 21.2. The patch against FSF Emacs 20.3.4 is identical apart from line numbers. In particular, this means that file-symlink-p doesn't run its efs-file-symlink-p handler and merely returns nil. This leads to infinite recursion in efs-internal-file-directory-p as the attached backtrace demonstrates. To reproduce: * rebuild emacs with S_IFLNK undefined. Actually its only src/fileio.c that needs recompiling so this can be done by inserting "#undef S_IFLNK" after the #includes in src/fileio.c. * xemacs -vanilla * C-x C-f /ftp.xemacs.org:/pub * Hit Return on the "xemacs" symlink. Suggested ugly workaround for efs: In efs-chase-symlinks replace the call to file-symlink-p with: (if (efs-ftp-path file) (efs-file-symlink-p file) (file-symlink-p file)) There are calls to file-symlink-p in efs-dired-compress-file and efs-recover-file that look like they should be replaced with an explicit call efs-file-symlink-p. (efs-internal-file-truename already contains an explicit call to efs-file-symlink-p). -- Jonathan. Emacs : XEmacs 21.2 "Ares" [Lucid] (i586-pc-win32) of Sat Jan 09 1999 on MARGINAL Package: efs efs believes that the host type of ftp.xemacs.org is unix. current state: ============== (setq efs-cu-version "1.18/1.12" efs-defun-version "1.18/1.1" efs-dired-version "1.18/1.32" efs-dump-version "1.18/1.2" efs-fnh-version "1.18/1.4" efs-netrc-version "1.18/1.2" efs-ovwrt-version "1.18/1.3" efs-report-version "1.18/1.10" efs-version "1.18/1.57" efs-x19.15-version "1.18/1.2" efs-36-bit-binary-file-name-regexp nil efs-anonymous-umask nil efs-auto-save 0 efs-auto-save-remotely nil efs-backup-by-copying nil efs-binary-file-host-regexp nil efs-binary-file-name-regexp "\\.\\([zZ]\\|t?gz\\|lzh\\|arc\\|zip\\|zoo\\|ta[rz]\\|dvi\\|sit\\|ps\\|elc\\|gif\\|Z-part-..\\|tpz\\|exe\\|[jm]pg\\|TZ[a-z]?\\|lib\\)\\(~\\|~[0-9]+~\\)?$\\|\\.\\(ARC\\|ELC\\|TAGS\\|EXE\\|ZIP\\|DVI|ZOO\\|GIF\\|T?GZ\\|[JM]PG\\)\\([.#;][0-9]+\\)?$" efs-buffer-name-case nil efs-compute-remote-buffer-file-truename nil efs-debug-ftp-connection nil efs-ding-on-chmod-failure t efs-ding-on-umask-failure t efs-disable-netrc-security-check nil efs-expire-ftp-buffers t efs-ftp-buffer-expire-time nil efs-ftp-program-args '("-i" "-n" "-g" "-v") efs-ftp-prompt-regexp "^\\(ftp\\|Ftp\\|FTP\\)> *" efs-gateway-ftp-prompt-regexp "^\\(ftp\\|Ftp\\|FTP\\)> *" efs-gateway-hash-mark-size nil efs-gateway-incoming-binary-hm-size nil efs-generate-anonymous-password t efs-hash-mark-size 2048 efs-high-security-hosts nil efs-incoming-binary-hm-size nil efs-local-apollo-unix nil efs-ls-cache-max 5 efs-make-backup-files '(unix sysV-unix bsd-unix next-unix apollo-unix dumb-unix dumb-apollo-unix super-dumb-unix) efs-max-ftp-buffer-size 3000 efs-maximize-idle nil efs-message-interval 0 efs-nlist-cmd "ls" efs-nslookup-on-connect nil efs-nslookup-program nil efs-prompt-for-transfer-type nil efs-pty-check-retry-time 5 efs-pty-check-threshold 1000 efs-retry-time 5 efs-root-umask nil efs-send-hash t efs-set-modtimes-synchronously nil efs-short-circuit t efs-short-circuit-to-remote-root nil efs-suppress-abort-recursive-edit-and-then nil efs-text-file-name-regexp ".*" efs-treat-crlf-as-nl nil efs-umask nil efs-use-passive-mode nil efs-verbose t efs-verify-anonymous-modtime nil efs-verify-modtime-host-regexp ".*" efs-ftp-program-name "ftp" efs-ftp-program-args '("-i" "-n" "-g" "-v") efs-local-host-regexp ".*" efs-ftp-local-host-regexp ".*" efs-gateway-host nil efs-gateway-type nil reporter-version "3.35" features '(mail-abbrevs sendmail reporter efs-report hyper-apropos efs-dired cus-face font disp-table dired-faces dired-xemacs dired efs-x19\.15 efs-fnh passwd advice advice-preload efs-ovwrt efs-cu efs-netrc efs-defun comint ring efs efs-dump zenirc-autoloads xemacs-devel-autoloads xemacs-base-autoloads w3-autoloads vm-autoloads viper-autoloads view-process-autoloads vhdl-autoloads vc-autoloads tpu-autoloads tooltalk-autoloads tm-autoloads time-autoloads textools-autoloads text-modes-autoloads texinfo-autoloads supercite-autoloads strokes-autoloads speedbar-autoloads slider-autoloads sh-script-autoloads sgml-autoloads scheme-autoloads rmail-autoloads reftex-autoloads psgml-autoloads prog-modes-autoloads pcl-cvs-autoloads pc-autoloads os-utils-autoloads net-utils-autoloads misc-games-autoloads mine-autoloads mh-e-autoloads mew-autoloads mailcrypt-autoloads mail-lib-autoloads jde-autoloads ispell-autoloads ilisp-autoloads igrep-autoloads hm--html-menus-autoloads gnus-autoloads gnats-autoloads games-autoloads fsf-compat-autoloads frame-icon-autoloads forms-autoloads footnote-autoloads eudc-autoloads eterm-autoloads emerge-autoloads elib-autoloads edt-autoloads edit-utils-autoloads ediff-autoloads edebug-autoloads dired-autoloads debug-autoloads crisp-autoloads cookie-autoloads cc-mode-autoloads calendar-autoloads calc-autoloads c-support-autoloads bbdb-autoloads auctex-autoloads apel-autoloads ada-autoloads Sun-autoloads mule-base-autoloads egg-its-autoloads edict-autoloads efs-autoloads Standard-autoloads loadhist auto-show fontl-hooks menubar-items x-menubar dragdrop mouse mode-motion itimer auto-save lisp-mode easymenu iso8859-1 page buff-menu lib-complete help-nomule derived frame text-props obsolete cus-start custom widget cl-extra mini-cl cl cl-19 packages backquote very-early-lisp file-coding mswindows-scrollbars label combo edit button mswindows-resource bmp mswindows toolbar native-sound scrollbar network-streams subprocesses menubar md5 xemacs png gif jpeg xpm xbm lisp-float-type windows-nt dragdrop-api dialog devices window-system) ) -- Jonathan Harris | jhar(a)tardis.ed.ac.uk London, England | Jonathan.Harris(a)symbian.com Return value: nil file-symlink-p("/anonymous＠ftp.xemacs.org:/pub/xemacs") * (let ((target ...)) (if target (efs-chase-symlinks ...) file)) ) * efs-chase-symlinks("/anonymous＠ftp.xemacs.org:/pub/xemacs") (efs-internal-file-directory-p nil (efs-chase-symlinks (efs-internal-directory-file-name path))) ) (if (stringp file-ent) (efs-internal-file-directory-p nil (efs-chase-symlinks ...)) file-ent) ) (let ((file-ent ...)) (if (stringp file-ent) (efs-internal-file-directory-p nil ...) file-ent)) ) (or (string-equal (nth 2 parsed) "/") (let (...) (if ... ... file-ent))) ) (let ((parsed ...)) (or (string-equal ... "/") (let ... ...))) ) (lambda (path) (let (...) (or ... ...)))("/anonymous＠ftp.xemacs.org:/pub/xemacs") apply((lambda (path) (let (...) (or ... ...))) "/anonymous＠ftp.xemacs.org:/pub/xemacs") efs-internal-file-directory-p(nil "/anonymous＠ftp.xemacs.org:/pub/xemacs") (if (stringp file-ent) (efs-internal-file-directory-p nil (efs-chase-symlinks ...)) file-ent) ) (let ((file-ent ...)) (if (stringp file-ent) (efs-internal-file-directory-p nil ...) file-ent)) ) (or (string-equal (nth 2 parsed) "/") (let (...) (if ... ... file-ent))) ) (let ((parsed ...)) (or (string-equal ... "/") (let ... ...))) ) (lambda (path) (let (...) (or ... ...)))("/anonymous＠ftp.xemacs.org:/pub/xemacs") apply((lambda (path) (let (...) (or ... ...))) "/anonymous＠ftp.xemacs.org:/pub/xemacs") efs-internal-file-directory-p(unix "/anonymous＠ftp.xemacs.org:/pub/xemacs") (let* ((file ...) (parsed ...)) (efs-internal-file-directory-p (efs-host-type ... ...) file)) ) efs-file-directory-p("/anonymous＠ftp.xemacs.org:/pub/xemacs") apply(efs-file-directory-p "/anonymous＠ftp.xemacs.org:/pub/xemacs") (if handler (apply handler args) (let (... ...) (apply operation args))) ) (let ((handler ...)) (if handler (apply handler args) (let ... ...))) ) efs-file-handler-function(file-directory-p "/anonymous＠ftp.xemacs.org:/pub/xemacs") file-directory-p("/anonymous＠ftp.xemacs.org:/pub/xemacs") apply(file-directory-p "/anonymous＠ftp.xemacs.org:/pub/xemacs") dired-handler-fn(file-directory-p "/anonymous＠ftp.xemacs.org:/pub/xemacs") file-directory-p("/anonymous＠ftp.xemacs.org:/pub/xemacs") find-file-noselect("/anonymous＠ftp.xemacs.org:/pub/xemacs") find-file("/anonymous＠ftp.xemacs.org:/pub/xemacs") (lambda nil "In dired, visit the file or directory named on this line.\nNote: This function has been modified to work with efs." (interactive) (find-file (if ... ... ...)))() call-interactively(dired-advertised-find-file) --- fileio.c.bak Sat Jan 02 04:42:24 1999 +++ fileio.c Sat Jan 09 22:48:46 1999 ＠＠ -2072,7 +2068,6 ＠＠ return Qnil; } -#ifdef S_IFLNK DEFUN ("make-symbolic-link", Fmake_symbolic_link, 2, 3, "FMake symbolic link to file: \nFMake symbolic link to file %s: \np", /* Make a symbolic link to FILENAME, named LINKNAME. Both args strings. ＠＠ -2111,6 +2106,7 ＠＠ RETURN_UNGCPRO (call4 (handler, Qmake_symbolic_link, filename, linkname, ok_if_already_exists)); +#ifdef S_IFLNK if (NILP (ok_if_already_exists) || INTP (ok_if_already_exists)) barf_or_query_if_file_exists (linkname, "make it a link", ＠＠ -2119,6 +2115,7 ＠＠ unlink ((char *) XSTRING_DATA (linkname)); if (0 > symlink ((char *) XSTRING_DATA (filename), (char *) XSTRING_DATA (linkname))) +#endif /* S_IFLNK */ { report_file_error ("Making symbolic link", list2 (filename, linkname)); ＠＠ -2126,7 +2123,6 ＠＠ UNGCPRO; return Qnil; } -#endif /* S_IFLNK */ #ifdef HPUX_NET ＠＠ -2353,11 +2349,6 ＠＠ (filename)) { /* This function can GC. GC checked 1997.04.10. */ -#ifdef S_IFLNK - char *buf; - int bufsize; - int valsize; - Lisp_Object val; Lisp_Object handler; struct gcpro gcpro1; ＠＠ -2372,25 +2363,33 ＠＠ if (!NILP (handler)) return call2 (handler, Qfile_symlink_p, filename); - bufsize = 100; - while (1) - { - buf = xnew_array_and_zero (char, bufsize); - valsize = readlink ((char *) XSTRING_DATA (filename), - buf, bufsize); - if (valsize < bufsize) break; - /* Buffer was not long enough */ - xfree (buf); - bufsize *= 2; - } - if (valsize == -1) - { - xfree (buf); - return Qnil; - } - val = make_string ((Bufbyte *) buf, valsize); - xfree (buf); - return val; +#ifdef S_IFLNK + { + char *buf; + int bufsize; + int valsize; + Lisp_Object val; + + bufsize = 100; + while (1) + { + buf = xnew_array_and_zero (char, bufsize); + valsize = readlink ((char *) XSTRING_DATA (filename), + buf, bufsize); + if (valsize < bufsize) break; + /* Buffer was not long enough */ + xfree (buf); + bufsize *= 2; + } + if (valsize == -1) + { + xfree (buf); + return Qnil; + } + val = make_string ((Bufbyte *) buf, valsize); + xfree (buf); + return val; + } #else /* not S_IFLNK */ return Qnil; #endif /* not S_IFLNK */ ＠＠ -4210,9 +4209,7 ＠＠ DEFSUBR (Fdelete_file); DEFSUBR (Frename_file); DEFSUBR (Fadd_name_to_file); -#ifdef S_IFLNK DEFSUBR (Fmake_symbolic_link); -#endif /* S_IFLNK */ #ifdef HPUX_NET DEFSUBR (Fsysnetunam); #endif /* HPUX_NET */