diff options
Diffstat (limited to 'lisp/eshell/esh-io.el')
| -rw-r--r-- | lisp/eshell/esh-io.el | 170 |
1 files changed, 108 insertions, 62 deletions
diff --git a/lisp/eshell/esh-io.el b/lisp/eshell/esh-io.el index 4620565f857..90826a312b3 100644 --- a/lisp/eshell/esh-io.el +++ b/lisp/eshell/esh-io.el @@ -116,16 +116,22 @@ from executing while Emacs is redisplaying." :group 'eshell-io) (defcustom eshell-virtual-targets - '(("/dev/eshell" eshell-interactive-print nil) + '(;; The literal string "/dev/null" is intentional here. It just + ;; provides compatibility so that users can redirect to + ;; "/dev/null" no matter the actual value of `null-device'. + ("/dev/null" (lambda (_mode) (throw 'eshell-null-device t)) t) + ("/dev/eshell" eshell-interactive-print nil) ("/dev/kill" (lambda (mode) - (if (eq mode 'overwrite) - (kill-new "")) - 'eshell-kill-append) t) + (when (eq mode 'overwrite) + (kill-new "")) + #'eshell-kill-append) + t) ("/dev/clip" (lambda (mode) - (if (eq mode 'overwrite) - (let ((select-enable-clipboard t)) - (kill-new ""))) - 'eshell-clipboard-append) t)) + (when (eq mode 'overwrite) + (let ((select-enable-clipboard t)) + (kill-new ""))) + #'eshell-clipboard-append) + t)) "Map virtual devices name to Emacs Lisp functions. If the user specifies any of the filenames above as a redirection target, the function in the second element will be called. @@ -138,10 +144,8 @@ function. The output function is then called repeatedly with single strings, which represents successive pieces of the output of the command, until nil -is passed, meaning EOF. - -NOTE: /dev/null is handled specially as a virtual target, and should -not be added to this variable." +is passed, meaning EOF." + :version "30.1" :type '(repeat (list (string :tag "Target") function @@ -291,25 +295,58 @@ describing the mode, e.g. for using with `eshell-get-target'.") (defun eshell-create-handles (stdout output-mode &optional stderr error-mode) "Create a new set of file handles for a command. -The default location for standard output and standard error will go to -STDOUT and STDERR, respectively. -OUTPUT-MODE and ERROR-MODE are either `overwrite', `append' or `insert'; -a nil value of mode defaults to `insert'." +The default target for standard output and standard error will +go to STDOUT and STDERR, respectively. OUTPUT-MODE and +ERROR-MODE are either `overwrite', `append' or `insert'; a nil +value of mode defaults to `insert'. + +The result is a vector of file handles. Each handle is of the form: + + ((TARGETS . REF-COUNT) DEFAULT) + +TARGETS is a list of destinations for output. REF-COUNT is the +number of references to this handle (initially 1); see +`eshell-protect-handles' and `eshell-close-handles'. DEFAULT is +non-nil if handle has its initial default value (always t after +calling this function)." (let* ((handles (make-vector eshell-number-of-handles nil)) - (output-target (eshell-get-target stdout output-mode)) - (error-target (if stderr - (eshell-get-target stderr error-mode) - output-target))) - (aset handles eshell-output-handle (cons output-target 1)) - (aset handles eshell-error-handle (cons error-target 1)) + (output-target + (let ((target (eshell-get-target stdout output-mode))) + (cons (when target (list target)) 1))) + (error-target + (if stderr + (let ((target (eshell-get-target stderr error-mode))) + (cons (when target (list target)) 1)) + (cl-incf (cdr output-target)) + output-target))) + (aset handles eshell-output-handle (list output-target t)) + (aset handles eshell-error-handle (list error-target t)) handles)) +(defun eshell-duplicate-handles (handles &optional steal-p) + "Create a duplicate of the file handles in HANDLES. +This uses the targets of each handle in HANDLES, incrementing its +reference count by one (unless STEAL-P is non-nil). These +targets are shared between the original set of handles and the +new one, so the targets are only closed when the reference count +drops to 0 (see `eshell-close-handles'). + +This function also sets the DEFAULT field for each handle to +t (see `eshell-create-handles'). Unlike the targets, this value +is not shared with the original handles." + (let ((dup-handles (make-vector eshell-number-of-handles nil))) + (dotimes (idx eshell-number-of-handles) + (when-let ((handle (aref handles idx))) + (unless steal-p + (cl-incf (cdar handle))) + (aset dup-handles idx (list (car handle) t)))) + dup-handles)) + (defun eshell-protect-handles (handles) "Protect the handles in HANDLES from a being closed." (dotimes (idx eshell-number-of-handles) - (when (aref handles idx) - (setcdr (aref handles idx) - (1+ (cdr (aref handles idx)))))) + (when-let ((handle (aref handles idx))) + (cl-incf (cdar handle)))) handles) (defun eshell-close-handles (&optional exit-code result handles) @@ -327,42 +364,56 @@ the value already set in `eshell-last-command-result'." (when result (cl-assert (eq (car result) 'quote)) (setq eshell-last-command-result (cadr result))) - (let ((handles (or handles eshell-current-handles))) + (let ((handles (or handles eshell-current-handles)) + (succeeded (= eshell-last-command-status 0))) (dotimes (idx eshell-number-of-handles) - (when-let ((handle (aref handles idx))) - (setcdr handle (1- (cdr handle))) - (when (= (cdr handle) 0) - (dolist (target (ensure-list (car (aref handles idx)))) - (eshell-close-target target (= eshell-last-command-status 0))) - (setcar handle nil)))))) + (eshell-close-handle (aref handles idx) succeeded)))) + +(defun eshell-close-handle (handle status) + "Close a single HANDLE, taking refcounts into account. +This will pass STATUS to each target for the handle, which should +be a non-nil value on successful termination." + (when handle + (cl-assert (> (cdar handle) 0) + "Attempted to close a handle with 0 references") + (when (and (> (cdar handle) 0) + (= (cl-decf (cdar handle)) 0)) + (dolist (target (caar handle)) + (eshell-close-target target status)) + (setcar (car handle) nil)))) (defun eshell-set-output-handle (index mode &optional target handles) "Set handle INDEX for the current HANDLES to point to TARGET using MODE. -If HANDLES is nil, use `eshell-current-handles'." +If HANDLES is nil, use `eshell-current-handles'. + +If the handle is currently set to its default value (see +`eshell-create-handles'), this will overwrite the targets with +the new target. Otherwise, it will append the new target to the +current list of targets." (when target - (let ((handles (or handles eshell-current-handles))) - (if (and (stringp target) - (string= target (null-device))) - (aset handles index nil) - (let ((where (eshell-get-target target mode)) - (current (car (aref handles index)))) - (if (listp current) - (unless (member where current) - (setq current (append current (list where)))) - (setq current (list where))) - (if (not (aref handles index)) - (aset handles index (cons nil 1))) - (setcar (aref handles index) current)))))) + (let* ((handles (or handles eshell-current-handles)) + (handle (or (aref handles index) + (aset handles index (list (cons nil 1) nil)))) + (defaultp (cadr handle))) + (when defaultp + (cl-decf (cdar handle)) + (setcar handle (cons nil 1))) + (catch 'eshell-null-device + (let ((current (caar handle)) + (where (eshell-get-target target mode))) + (unless (member where current) + (setcar (car handle) (append current (list where)))))) + (setcar (cdr handle) nil)))) (defun eshell-copy-output-handle (index index-to-copy &optional handles) "Copy the handle INDEX-TO-COPY to INDEX for the current HANDLES. If HANDLES is nil, use `eshell-current-handles'." (let* ((handles (or handles eshell-current-handles)) (handle-to-copy (car (aref handles index-to-copy)))) - (setcar (aref handles index) - (if (listp handle-to-copy) - (copy-sequence handle-to-copy) - handle-to-copy)))) + (when handle-to-copy + (cl-incf (cdr handle-to-copy))) + (eshell-close-handle (aref handles index) nil) + (setcar (aref handles index) handle-to-copy))) (defun eshell-set-all-output-handles (mode &optional target handles) "Set output and error HANDLES to point to TARGET using MODE. @@ -493,9 +544,9 @@ INDEX is the handle index to check. If nil, check (let ((handles (or handles eshell-current-handles)) (index (or index eshell-output-handle))) (if (eq index 'all) - (and (eq (car (aref handles eshell-output-handle)) t) - (eq (car (aref handles eshell-error-handle)) t)) - (eq (car (aref handles index)) t)))) + (and (equal (caar (aref handles eshell-output-handle)) '(t)) + (equal (caar (aref handles eshell-error-handle)) '(t))) + (equal (caar (aref handles index)) '(t))))) (defvar eshell-print-queue nil) (defvar eshell-print-queue-count -1) @@ -602,15 +653,10 @@ Returns what was actually sent, or nil if nothing was sent." If HANDLE-INDEX is nil, output to `eshell-output-handle'. HANDLES is the set of file handles to use; if nil, use `eshell-current-handles'." - (let ((target (car (aref (or handles eshell-current-handles) - (or handle-index eshell-output-handle))))) - (if (listp target) - (while target - (eshell-output-object-to-target object (car target)) - (setq target (cdr target))) - (eshell-output-object-to-target object target) - ;; Explicitly return nil to match the list case above. - nil))) + (let ((targets (caar (aref (or handles eshell-current-handles) + (or handle-index eshell-output-handle))))) + (dolist (target targets) + (eshell-output-object-to-target object target)))) (provide 'esh-io) ;;; esh-io.el ends here |