[bpt/emacs.git] / lisp / eshell / esh-ext.el

;;; esh-ext.el --- commands external to Eshell

;; Copyright (C) 1999-2011  Free Software Foundation, Inc.

;; Author: John Wiegley <johnw@gnu.org>

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; To force a command to invoked external, either provide an explicit
;; pathname for the command argument, or prefix the command name with
;; an asterix character.  Example:
;;
;;   grep        ; make invoke `grep' Lisp function, or `eshell/grep'
;;   /bin/grep   ; will definitely invoke /bin/grep
;;   *grep        ; will also invoke /bin/grep

;;; Code:

(provide 'esh-ext)

(eval-when-compile
  (require 'cl)
  (require 'esh-cmd))
(require 'esh-util)

(defgroup eshell-ext nil
  "External commands are invoked when operating system executables are
loaded into memory, thus beginning a new process."
  :tag "External commands"
  :group 'eshell)

;;; User Variables:

(defcustom eshell-ext-load-hook '(eshell-ext-initialize)
  "A hook that gets run when `eshell-ext' is loaded."
  :type 'hook
  :group 'eshell-ext)

(defcustom eshell-binary-suffixes exec-suffixes
  "A list of suffixes used when searching for executable files."
  :type '(repeat string)
  :group 'eshell-ext)

(defcustom eshell-force-execution nil
  "If non-nil, try to execute binary files regardless of permissions.
This can be useful on systems like Windows, where the operating system
doesn't happen to honor the permission bits in certain cases; or in
cases where you want to associate an interpreter with a particular
kind of script file, but the language won't let you but a '#!'
interpreter line in the file, and you don't want to make it executable
since nothing else but Eshell will be able to understand
`eshell-interpreter-alist'."
  :type 'boolean
  :group 'eshell-ext)

(defun eshell-search-path (name)
  "Search the environment path for NAME."
  (if (file-name-absolute-p name)
      name
    (let ((list (eshell-parse-colon-path eshell-path-env))
	  suffixes n1 n2 file)
      (while list
	(setq n1 (concat (car list) name))
	(setq suffixes eshell-binary-suffixes)
	(while suffixes
	  (setq n2 (concat n1 (car suffixes)))
	  (if (and (or (file-executable-p n2)
		       (and eshell-force-execution
			    (file-readable-p n2)))
		   (not (file-directory-p n2)))
	      (setq file n2 suffixes nil list nil))
	  (setq suffixes (cdr suffixes)))
	(setq list (cdr list)))
      file)))

(defcustom eshell-windows-shell-file
  (if (eshell-under-windows-p)
      (if (string-match "\\(\\`cmdproxy\\|sh\\)\\.\\(com\\|exe\\)"
			shell-file-name)
	  (or (eshell-search-path "cmd.exe")
	      (eshell-search-path "command.com"))
	shell-file-name))
  "The name of the shell command to use for DOS/Windows batch files.
This defaults to nil on non-Windows systems, where this variable is
wholly ignored."
  :type '(choice file (const nil))
  :group 'eshell-ext)

(defsubst eshell-invoke-batch-file (&rest args)
  "Invoke a .BAT or .CMD file on DOS/Windows systems."
  ;; since CMD.EXE can't handle forward slashes in the initial
  ;; argument...
  (setcar args (subst-char-in-string ?/ ?\\ (car args)))
  (throw 'eshell-replace-command
	 (eshell-parse-command eshell-windows-shell-file (cons "/c" args))))

(defcustom eshell-interpreter-alist
  (if (eshell-under-windows-p)
      '(("\\.\\(bat\\|cmd\\)\\'" . eshell-invoke-batch-file)))
  "An alist defining interpreter substitutions.
Each member is a cons cell of the form:

  (MATCH . INTERPRETER)

MATCH should be a regexp, which is matched against the command name,
or a function.  If either returns a non-nil value, then INTERPRETER
will be used for that command.

If INTERPRETER is a string, it will be called as the command name,
with the original command name passed as the first argument, with all
subsequent arguments following.  If INTERPRETER is a function, it will
be called with all of those arguments.  Note that interpreter
functions should throw `eshell-replace-command' with the alternate
command form, or they should return a value compatible with the
possible return values of `eshell-external-command', which see."
  :type '(repeat (cons (choice regexp (function :tag "Predicate"))
		       (choice string (function :tag "Interpreter"))))
  :group 'eshell-ext)

(defcustom eshell-alternate-command-hook nil
  "A hook run whenever external command lookup fails.
If a functions wishes to provide an alternate command, they must throw
it using the tag `eshell-replace-command'.  This is done because the
substituted command need not be external at all, and therefore must be
passed up to a higher level for re-evaluation.

Or, if the function returns a filename, that filename will be invoked
with the current command arguments rather than the command specified
by the user on the command line."
  :type 'hook
  :group 'eshell-ext)

(defcustom eshell-command-interpreter-max-length 256
  "The maximum length of any command interpreter string, plus args."
  :type 'integer
  :group 'eshell-ext)

(defcustom eshell-explicit-command-char ?*
  "If this char occurs before a command name, call it externally.
That is, although `vi' may be an alias, `\vi' will always call the
external version."
  :type 'character
  :group 'eshell-ext)

;;; Functions:

(defun eshell-ext-initialize ()
  "Initialize the external command handling code."
  (add-hook 'eshell-named-command-hook 'eshell-explicit-command nil t))

(defun eshell-explicit-command (command args)
  "If a command name begins with `*', call it externally always.
This bypasses all Lisp functions and aliases."
  (when (and (> (length command) 1)
	     (eq (aref command 0) eshell-explicit-command-char))
    (let ((cmd (eshell-search-path (substring command 1))))
      (if cmd
	  (or (eshell-external-command cmd args)
	      (error "%s: external command failed" cmd))
	(error "%s: external command not found"
	       (substring command 1))))))

(defun eshell-remote-command (command args)
  "Insert output from a remote COMMAND, using ARGS.
A remote command is something that executes on a different machine.
An external command simply means external to Emacs.

Note that this function is very crude at the moment.  It gathers up
all the output from the remote command, and sends it all at once,
causing the user to wonder if anything's really going on..."
  (let ((outbuf (generate-new-buffer " *eshell remote output*"))
	(errbuf (generate-new-buffer " *eshell remote error*"))
	(exitcode 1))
    (unwind-protect
	(progn
	  (setq exitcode
		(shell-command
		 (mapconcat 'shell-quote-argument
			    (append (list command) args) " ")
		 outbuf errbuf))
	  (eshell-print (with-current-buffer outbuf (buffer-string)))
	  (eshell-error (with-current-buffer errbuf (buffer-string))))
      (eshell-close-handles exitcode 'nil)
      (kill-buffer outbuf)
      (kill-buffer errbuf))))

(defun eshell-external-command (command args)
  "Insert output from an external COMMAND, using ARGS."
  (setq args (eshell-stringify-list (eshell-flatten-list args)))
  (if (string-equal (file-remote-p default-directory 'method) "ftp")
      (eshell-remote-command command args))
  (let ((interp (eshell-find-interpreter command)))
    (assert interp)
    (if (functionp (car interp))
	(apply (car interp) (append (cdr interp) args))
      (eshell-gather-process-output
       (car interp) (append (cdr interp) args)))))

(defun eshell/addpath (&rest args)
  "Add a set of paths to PATH."
  (eshell-eval-using-options
   "addpath" args
   '((?b "begin" nil prepend "add path element at beginning")
     (?h "help" nil nil  "display this usage message")
     :usage "[-b] PATH
Adds the given PATH to $PATH.")
   (if args
       (progn
	 (if prepend
	     (setq args (nreverse args)))
	 (while args
	   (setenv "PATH"
		   (if prepend
		       (concat (car args) path-separator
			       (getenv "PATH"))
		     (concat (getenv "PATH") path-separator
			     (car args))))
	   (setq args (cdr args))))
     (let ((paths (parse-colon-path (getenv "PATH"))))
       (while paths
	 (eshell-printn (car paths))
	 (setq paths (cdr paths)))))))

(put 'eshell/addpath 'eshell-no-numeric-conversions t)

(defun eshell-script-interpreter (file)
  "Extract the script to run from FILE, if it has #!<interp> in it.
Return nil, or a list of the form:

  (INTERPRETER [ARGS] FILE)"
  (let ((maxlen eshell-command-interpreter-max-length))
    (if (and (file-readable-p file)
	     (file-regular-p file))
	(with-temp-buffer
	  (insert-file-contents-literally file nil 0 maxlen)
	  (if (looking-at "#![ \t]*\\([^ \r\t\n]+\\)\\([ \t]+\\(.+\\)\\)?")
	      (if (match-string 3)
		  (list (match-string 1)
			(match-string 3)
			file)
		(list (match-string 1)
		      file)))))))

(defun eshell-find-interpreter (file &optional no-examine-p)
  "Find the command interpreter with which to execute FILE.
If NO-EXAMINE-P is non-nil, FILE will not be inspected for a script
line of the form #!<interp>."
  (let ((finterp
	 (catch 'found
	   (ignore
	    (eshell-for possible eshell-interpreter-alist
	      (cond
	       ((functionp (car possible))
		(and (funcall (car possible) file)
		     (throw 'found (cdr possible))))
	       ((stringp (car possible))
		(and (string-match (car possible) file)
		     (throw 'found (cdr possible))))
	       (t
		(error "Invalid interpreter-alist test"))))))))
    (if finterp                         ; first check
	(list finterp file)
      (let ((fullname (if (file-name-directory file) file
			(eshell-search-path file)))
	    (suffixes eshell-binary-suffixes))
	(if (and fullname (not (or eshell-force-execution
				   (file-executable-p fullname))))
	    (while suffixes
	      (let ((try (concat fullname (car suffixes))))
		(if (or (file-executable-p try)
			(and eshell-force-execution
			     (file-readable-p try)))
		    (setq fullname try suffixes nil)
		  (setq suffixes (cdr suffixes))))))
	(cond ((not (and fullname (file-exists-p fullname)))
	       (let ((name (or fullname file)))
		 (unless (setq fullname
			       (run-hook-with-args-until-success
				'eshell-alternate-command-hook file))
		   (error "%s: command not found" name))))
	      ((not (or eshell-force-execution
			(file-executable-p fullname)))
	       (error "%s: Permission denied" fullname)))
	(let (interp)
	  (unless no-examine-p
	    (setq interp (eshell-script-interpreter fullname))
	    (if interp
		(setq interp
		      (cons (car (eshell-find-interpreter (car interp) t))
			    (cdr interp)))))
	  (or interp (list fullname)))))))

;;; esh-ext.el ends here
Commit	Line	Data
60370d40	1	;;; esh-ext.el --- commands external to Eshell
affbf647	2
73b0cd50	3	;; Copyright (C) 1999-2011 Free Software Foundation, Inc.
affbf647	4
7de5b421 GM	5	;; Author: John Wiegley <johnw@gnu.org>
7de5b421 GM	6
affbf647 GM	7	;; This file is part of GNU Emacs.
affbf647 GM	8
4ee57b2a	9	;; GNU Emacs is free software: you can redistribute it and/or modify
affbf647	10	;; it under the terms of the GNU General Public License as published by
4ee57b2a GM	11	;; the Free Software Foundation, either version 3 of the License, or
4ee57b2a GM	12	;; (at your option) any later version.
affbf647 GM	13
	14	;; GNU Emacs is distributed in the hope that it will be useful,
	15	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	;; GNU General Public License for more details.
	18
	19	;; You should have received a copy of the GNU General Public License
4ee57b2a	20	;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
affbf647	21
affbf647 GM	22	;;; Commentary:
	23
	24	;; To force a command to invoked external, either provide an explicit
	25	;; pathname for the command argument, or prefix the command name with
	26	;; an asterix character. Example:
	27	;;
	28	;; grep ; make invoke `grep' Lisp function, or `eshell/grep'
	29	;; /bin/grep ; will definitely invoke /bin/grep
	30	;; *grep ; will also invoke /bin/grep
	31
8c7309fe GM	32	;;; Code:
8c7309fe GM	33
4e6cc05c GM	34	(provide 'esh-ext)
	35
	36	(eval-when-compile
fc17acd1	37	(require 'cl)
4e6cc05c GM	38	(require 'esh-cmd))
	39	(require 'esh-util)
	40
	41	(defgroup eshell-ext nil
	42	"External commands are invoked when operating system executables are
	43	loaded into memory, thus beginning a new process."
	44	:tag "External commands"
	45	:group 'eshell)
	46
affbf647 GM	47	;;; User Variables:
	48
	49	(defcustom eshell-ext-load-hook '(eshell-ext-initialize)
ec60da52	50	"A hook that gets run when `eshell-ext' is loaded."
affbf647 GM	51	:type 'hook
	52	:group 'eshell-ext)
	53
194c8d98	54	(defcustom eshell-binary-suffixes exec-suffixes
ec60da52	55	"A list of suffixes used when searching for executable files."
affbf647 GM	56	:type '(repeat string)
	57	:group 'eshell-ext)
	58
	59	(defcustom eshell-force-execution nil
ec60da52	60	"If non-nil, try to execute binary files regardless of permissions.
affbf647 GM	61	This can be useful on systems like Windows, where the operating system
	62	doesn't happen to honor the permission bits in certain cases; or in
	63	cases where you want to associate an interpreter with a particular
	64	kind of script file, but the language won't let you but a '#!'
	65	interpreter line in the file, and you don't want to make it executable
	66	since nothing else but Eshell will be able to understand
	67	`eshell-interpreter-alist'."
	68	:type 'boolean
	69	:group 'eshell-ext)
	70
	71	(defun eshell-search-path (name)
	72	"Search the environment path for NAME."
	73	(if (file-name-absolute-p name)
	74	name
605a20a9	75	(let ((list (eshell-parse-colon-path eshell-path-env))
affbf647 GM	76	suffixes n1 n2 file)
	77	(while list
	78	(setq n1 (concat (car list) name))
	79	(setq suffixes eshell-binary-suffixes)
	80	(while suffixes
	81	(setq n2 (concat n1 (car suffixes)))
	82	(if (and (or (file-executable-p n2)
	83	(and eshell-force-execution
	84	(file-readable-p n2)))
	85	(not (file-directory-p n2)))
	86	(setq file n2 suffixes nil list nil))
	87	(setq suffixes (cdr suffixes)))
	88	(setq list (cdr list)))
	89	file)))
	90
	91	(defcustom eshell-windows-shell-file
	92	(if (eshell-under-windows-p)
	93	(if (string-match "\\(\\`cmdproxy\\\|sh\\)\\.\\(com\\\|exe\\)"
	94	shell-file-name)
	95	(or (eshell-search-path "cmd.exe")
b0c9a334	96	(eshell-search-path "command.com"))
affbf647	97	shell-file-name))
ec60da52	98	"The name of the shell command to use for DOS/Windows batch files.
affbf647 GM	99	This defaults to nil on non-Windows systems, where this variable is
affbf647 GM	100	wholly ignored."
f569d4c4	101	:type '(choice file (const nil))
affbf647 GM	102	:group 'eshell-ext)
	103
	104	(defsubst eshell-invoke-batch-file (&rest args)
	105	"Invoke a .BAT or .CMD file on DOS/Windows systems."
	106	;; since CMD.EXE can't handle forward slashes in the initial
	107	;; argument...
6b0e3e4d	108	(setcar args (subst-char-in-string ?/ ?\\ (car args)))
affbf647	109	(throw 'eshell-replace-command
ca7aae91	110	(eshell-parse-command eshell-windows-shell-file (cons "/c" args))))
affbf647 GM	111
	112	(defcustom eshell-interpreter-alist
	113	(if (eshell-under-windows-p)
	114	'(("\\.\\(bat\\\|cmd\\)\\'" . eshell-invoke-batch-file)))
ec60da52	115	"An alist defining interpreter substitutions.
affbf647 GM	116	Each member is a cons cell of the form:
	117
	118	(MATCH . INTERPRETER)
	119
	120	MATCH should be a regexp, which is matched against the command name,
	121	or a function. If either returns a non-nil value, then INTERPRETER
	122	will be used for that command.
	123
	124	If INTERPRETER is a string, it will be called as the command name,
	125	with the original command name passed as the first argument, with all
	126	subsequent arguments following. If INTERPRETER is a function, it will
	127	be called with all of those arguments. Note that interpreter
	128	functions should throw `eshell-replace-command' with the alternate
	129	command form, or they should return a value compatible with the
	130	possible return values of `eshell-external-command', which see."
	131	:type '(repeat (cons (choice regexp (function :tag "Predicate"))
	132	(choice string (function :tag "Interpreter"))))
	133	:group 'eshell-ext)
	134
	135	(defcustom eshell-alternate-command-hook nil
ec60da52	136	"A hook run whenever external command lookup fails.
affbf647 GM	137	If a functions wishes to provide an alternate command, they must throw
	138	it using the tag `eshell-replace-command'. This is done because the
	139	substituted command need not be external at all, and therefore must be
	140	passed up to a higher level for re-evaluation.
	141
	142	Or, if the function returns a filename, that filename will be invoked
	143	with the current command arguments rather than the command specified
	144	by the user on the command line."
	145	:type 'hook
	146	:group 'eshell-ext)
	147
	148	(defcustom eshell-command-interpreter-max-length 256
ec60da52	149	"The maximum length of any command interpreter string, plus args."
affbf647 GM	150	:type 'integer
	151	:group 'eshell-ext)
	152
1228240f	153	(defcustom eshell-explicit-command-char ?*
ec60da52	154	"If this char occurs before a command name, call it externally.
451eaf8d RS	155	That is, although `vi' may be an alias, `\vi' will always call the
451eaf8d RS	156	external version."
1228240f JW	157	:type 'character
	158	:group 'eshell-ext)
	159
affbf647 GM	160	;;; Functions:
	161
	162	(defun eshell-ext-initialize ()
	163	"Initialize the external command handling code."
affbf647 GM	164	(add-hook 'eshell-named-command-hook 'eshell-explicit-command nil t))
	165
	166	(defun eshell-explicit-command (command args)
	167	"If a command name begins with `*', call it externally always.
	168	This bypasses all Lisp functions and aliases."
	169	(when (and (> (length command) 1)
1228240f	170	(eq (aref command 0) eshell-explicit-command-char))
affbf647 GM	171	(let ((cmd (eshell-search-path (substring command 1))))
	172	(if cmd
	173	(or (eshell-external-command cmd args)
	174	(error "%s: external command failed" cmd))
	175	(error "%s: external command not found"
	176	(substring command 1))))))
	177
605a20a9	178	(defun eshell-remote-command (command args)
affbf647 GM	179	"Insert output from a remote COMMAND, using ARGS.
	180	A remote command is something that executes on a different machine.
	181	An external command simply means external to Emacs.
	182
	183	Note that this function is very crude at the moment. It gathers up
	184	all the output from the remote command, and sends it all at once,
	185	causing the user to wonder if anything's really going on..."
	186	(let ((outbuf (generate-new-buffer " eshell remote output"))
	187	(errbuf (generate-new-buffer " eshell remote error"))
	188	(exitcode 1))
	189	(unwind-protect
	190	(progn
	191	(setq exitcode
605a20a9 MA	192	(shell-command
	193	(mapconcat 'shell-quote-argument
	194	(append (list command) args) " ")
	195	outbuf errbuf))
937e6a56 SM	196	(eshell-print (with-current-buffer outbuf (buffer-string)))
937e6a56 SM	197	(eshell-error (with-current-buffer errbuf (buffer-string))))
affbf647 GM	198	(eshell-close-handles exitcode 'nil)
	199	(kill-buffer outbuf)
	200	(kill-buffer errbuf))))
	201
	202	(defun eshell-external-command (command args)
	203	"Insert output from an external COMMAND, using ARGS."
	204	(setq args (eshell-stringify-list (eshell-flatten-list args)))
605a20a9 MA	205	(if (string-equal (file-remote-p default-directory 'method) "ftp")
	206	(eshell-remote-command command args))
	207	(let ((interp (eshell-find-interpreter command)))
	208	(assert interp)
	209	(if (functionp (car interp))
	210	(apply (car interp) (append (cdr interp) args))
	211	(eshell-gather-process-output
	212	(car interp) (append (cdr interp) args)))))
affbf647 GM	213
	214	(defun eshell/addpath (&rest args)
	215	"Add a set of paths to PATH."
	216	(eshell-eval-using-options
	217	"addpath" args
	218	'((?b "begin" nil prepend "add path element at beginning")
	219	(?h "help" nil nil "display this usage message")
	220	:usage "[-b] PATH
	221	Adds the given PATH to $PATH.")
	222	(if args
	223	(progn
	224	(if prepend
	225	(setq args (nreverse args)))
	226	(while args
	227	(setenv "PATH"
	228	(if prepend
	229	(concat (car args) path-separator
	230	(getenv "PATH"))
	231	(concat (getenv "PATH") path-separator
	232	(car args))))
	233	(setq args (cdr args))))
	234	(let ((paths (parse-colon-path (getenv "PATH"))))
	235	(while paths
	236	(eshell-printn (car paths))
	237	(setq paths (cdr paths)))))))
	238
127fd3c2 JW	239	(put 'eshell/addpath 'eshell-no-numeric-conversions t)
127fd3c2 JW	240
affbf647 GM	241	(defun eshell-script-interpreter (file)
	242	"Extract the script to run from FILE, if it has #!<interp> in it.
	243	Return nil, or a list of the form:
	244
	245	(INTERPRETER [ARGS] FILE)"
	246	(let ((maxlen eshell-command-interpreter-max-length))
	247	(if (and (file-readable-p file)
	248	(file-regular-p file))
	249	(with-temp-buffer
	250	(insert-file-contents-literally file nil 0 maxlen)
30104690	251	(if (looking-at "#![ \t]*\\([^ \r\t\n]+\\)\\([ \t]+\\(.+\\)\\)?")
affbf647 GM	252	(if (match-string 3)
	253	(list (match-string 1)
	254	(match-string 3)
	255	file)
	256	(list (match-string 1)
	257	file)))))))
	258
	259	(defun eshell-find-interpreter (file &optional no-examine-p)
	260	"Find the command interpreter with which to execute FILE.
	261	If NO-EXAMINE-P is non-nil, FILE will not be inspected for a script
	262	line of the form #!<interp>."
	263	(let ((finterp
	264	(catch 'found
	265	(ignore
	266	(eshell-for possible eshell-interpreter-alist
	267	(cond
	268	((functionp (car possible))
	269	(and (funcall (car possible) file)
	270	(throw 'found (cdr possible))))
	271	((stringp (car possible))
	272	(and (string-match (car possible) file)
	273	(throw 'found (cdr possible))))
	274	(t
	275	(error "Invalid interpreter-alist test"))))))))
	276	(if finterp ; first check
	277	(list finterp file)
	278	(let ((fullname (if (file-name-directory file) file
	279	(eshell-search-path file)))
	280	(suffixes eshell-binary-suffixes))
	281	(if (and fullname (not (or eshell-force-execution
	282	(file-executable-p fullname))))
	283	(while suffixes
	284	(let ((try (concat fullname (car suffixes))))
	285	(if (or (file-executable-p try)
	286	(and eshell-force-execution
	287	(file-readable-p try)))
	288	(setq fullname try suffixes nil)
	289	(setq suffixes (cdr suffixes))))))
	290	(cond ((not (and fullname (file-exists-p fullname)))
	291	(let ((name (or fullname file)))
	292	(unless (setq fullname
	293	(run-hook-with-args-until-success
	294	'eshell-alternate-command-hook file))
	295	(error "%s: command not found" name))))
	296	((not (or eshell-force-execution
	297	(file-executable-p fullname)))
	298	(error "%s: Permission denied" fullname)))
	299	(let (interp)
	300	(unless no-examine-p
	301	(setq interp (eshell-script-interpreter fullname))
	302	(if interp
	303	(setq interp
	304	(cons (car (eshell-find-interpreter (car interp) t))
	305	(cdr interp)))))
	306	(or interp (list fullname)))))))
	307
affbf647	308	;;; esh-ext.el ends here