New gui-selection-value consolidating x-selection-value.

* lisp/select.el (gui-selection-value-alist): New method.
(gui-selection-value): New function.
(x-selection-value): Make it an obsolete alias.
* lisp/simple.el (interprogram-paste-function): Default to gui-selection-value.
* lisp/w32-common-fns.el (w32-get-selection-value): Simplify.
(x-selection-value): Remove alias.
(interprogram-paste-function): Don't set.
(gui-selection-value): Define for w32.
* lisp/term/x-win.el (gui-selection-value): Define for x.
(x--selection-value): Rename from x--selection-value.
(interprogram-paste-function): Don't set.
* lisp/term/pc-win.el (w16-get-selection-value): Simplify.
(msdos-initialize-window-system): Don't set interprogram-paste-function.
(gui-selection-value): Define for pc.
* lisp/term/ns-win.el (x-selection-value): Remove.
(gui-selection-value): Define for ns, instead.
* lisp/term/common-win.el (x-setup-function-keys): Don't set
interprogram-paste-function.
* lisp/obsolete/mouse-sel.el (mouse-sel-get-selection-function):
Use gui-selection-value.

4 files changed, 71 insertions, 97 deletions

diff --git a/lisp/term/common-win.el b/lisp/term/common-win.el
index fcb9fd55bb1..d026ee8eabe 100644
--- a/lisp/term/common-win.el
+++ b/lisp/term/common-win.el
@@ -56,8 +56,7 @@
         (set-keymap-parent map (keymap-parent local-function-key-map))
         (set-keymap-parent local-function-key-map map))
       (when (featurep 'ns)
-	(setq interprogram-paste-function 'x-selection-value
-	      system-key-alist
+	(setq system-key-alist
 	      (list
 	       ;; These are special "keys" used to pass events from C to lisp.
 	       (cons (logior (lsh 0 16)   1) 'ns-power-off)
diff --git a/lisp/term/ns-win.el b/lisp/term/ns-win.el
index b1d3a00df0c..22e99d87968 100644
--- a/lisp/term/ns-win.el
+++ b/lisp/term/ns-win.el
@@ -736,27 +736,14 @@ See the documentation of `create-fontset-from-fontset-spec' for the format.")
   (if (not (stringp string)) (error "Nonstring given to pasteboard"))
   (ns-store-selection-internal 'CLIPBOARD string))
 
-;; We keep track of the last text selected here, so we can check the
-;; current selection against it, and avoid passing back our own text
-;; from x-selection-value.
-
 ;; Return the value of the current Nextstep selection.  For
 ;; compatibility with older Nextstep applications, this checks cut
 ;; buffer 0 before retrieving the value of the primary selection.
-(defun x-selection-value ()
-  (let (text)
-    ;; Consult the selection.  Treat empty strings as if they were unset.
-    (or text (setq text (ns-get-pasteboard)))
-    (if (string= text "") (setq text nil))
-    (cond
-     ((not text) nil)
-     ((eq text gui-last-selected-text) nil)
-     ((string= text gui-last-selected-text)
-      ;; Record the newer string, so subsequent calls can use the `eq' test.
-      (setq gui-last-selected-text text)
-      nil)
-     (t
-      (setq gui-last-selected-text text)))))
+(gui-method-define gui-selection-value ns #'ns-selection-value)
+(defun ns-selection-value ()
+  ;; Consult the selection.  Treat empty strings as if they were unset.
+  (if gui-select-enable-clipboard
+      (ns-get-pasteboard)))
 
 (defun ns-copy-including-secondary ()
   (interactive)
diff --git a/lisp/term/pc-win.el b/lisp/term/pc-win.el
index 3498937b4d2..a7507377bda 100644
--- a/lisp/term/pc-win.el
+++ b/lisp/term/pc-win.el
@@ -223,20 +223,9 @@ the operating system.")
   "Return the value of the current selection.
 Consult the selection.  Treat empty strings as if they were unset."
   (if gui-select-enable-clipboard
-      (let (text)
-	;; Don't die if x-get-selection signals an error.
-	(with-demoted-errors "w16-get-clipboard-data:%s"
-          (setq text (w16-get-clipboard-data)))
-	(if (string= text "") (setq text nil))
-	(cond
-	 ((not text) nil)
-	 ((eq text gui-last-selected-text) nil)
-	 ((string= text gui-last-selected-text)
-	  ;; Record the newer string, so subsequent calls can use the 'eq' test.
-	  (setq gui-last-selected-text text)
-	  nil)
-	 (t
-	  (setq gui-last-selected-text text))))))
+      ;; Don't die if x-get-selection signals an error.
+      (with-demoted-errors "w16-get-clipboard-data:%s"
+        (w16-get-clipboard-data))))
 
 ;; gui-selection-owner-p is used in simple.el.
 (gui-method-define gui-selection-owner-p pc #'w16-selection-owner-p)
@@ -380,7 +369,6 @@ Errors out because it is not supposed to be called, ever."
   (setq split-window-keep-point t)
   ;; Arrange for the kill and yank functions to set and check the
   ;; clipboard.
-  (setq interprogram-paste-function #'w16-get-selection-value)
   (menu-bar-enable-clipboard)
   (run-hooks 'terminal-init-msdos-hook))
 
@@ -398,6 +386,7 @@ Errors out because it is not supposed to be called, ever."
 (declare-function w16-set-clipboard-data "w16select.c"
 		  (string &optional ignored))
 (gui-method-define gui-select-text pc #'w16--select-text)
+(gui-method-define gui-selection-value pc #'w16-get-selection-value)
 (defun w16--select-text (text)
   (when gui-select-enable-clipboard
     (w16-set-clipboard-data text)))
diff --git a/lisp/term/x-win.el b/lisp/term/x-win.el
index a50f886c66a..d6848628bf3 100644
--- a/lisp/term/x-win.el
+++ b/lisp/term/x-win.el
@@ -1156,7 +1156,7 @@ as returned by `x-server-vendor'."
 
 ;; We keep track of the last text selected here, so we can check the
 ;; current selection against it, and avoid passing back our own text
-;; from x-selection-value.  We track both
+;; from x--selection-value.  We track both
 ;; separately in case another X application only sets one of them
 ;; we aren't fooled by the PRIMARY or CLIPBOARD selection staying the same.
 (defvar x-last-selected-text-clipboard nil
@@ -1222,73 +1222,72 @@ The value nil is the same as the list (UTF8_STRING COMPOUND_TEXT STRING)."
 ;; If this function is called twice and finds the same text,
 ;; it returns nil the second time.  This is so that a single
 ;; selection won't be added to the kill ring over and over.
-(defun x-selection-value ()
+(gui-method-define gui-selection-value x #'x--selection-value)
+(defun x--selection-value ()
   ;; With multi-tty, this function may be called from a tty frame.
-  (when (eq (framep (selected-frame)) 'x)
-    (let (clip-text primary-text)
-      (when x-select-enable-clipboard
-        (setq clip-text (x-selection-value-internal 'CLIPBOARD))
-        (if (string= clip-text "") (setq clip-text nil))
-
-        ;; Check the CLIPBOARD selection for 'newness', is it different
-        ;; from what we remembered them to be last time we did a
-        ;; cut/paste operation.
-        (setq clip-text
-              (cond ;; check clipboard
-               ((or (not clip-text) (string= clip-text ""))
-                (setq x-last-selected-text-clipboard nil))
-               ((eq      clip-text x-last-selected-text-clipboard) nil)
-               ((string= clip-text x-last-selected-text-clipboard)
-                ;; Record the newer string,
-                ;; so subsequent calls can use the `eq' test.
-                (setq x-last-selected-text-clipboard clip-text)
-                nil)
-               (t (setq x-last-selected-text-clipboard clip-text)))))
-
-      (when x-select-enable-primary
-	(setq primary-text (x-selection-value-internal 'PRIMARY))
-	;; Check the PRIMARY selection for 'newness', is it different
-	;; from what we remembered them to be last time we did a
-	;; cut/paste operation.
-	(setq primary-text
-	      (cond ;; check primary selection
-	       ((or (not primary-text) (string= primary-text ""))
-		(setq x-last-selected-text-primary nil))
-	       ((eq      primary-text x-last-selected-text-primary) nil)
-	       ((string= primary-text x-last-selected-text-primary)
-		;; Record the newer string,
-		;; so subsequent calls can use the `eq' test.
-		(setq x-last-selected-text-primary primary-text)
-		nil)
-	       (t
-		(setq x-last-selected-text-primary primary-text)))))
-
-      ;; As we have done one selection, clear this now.
-      (setq next-selection-coding-system nil)
-
-      ;; At this point we have recorded the current values for the
-      ;; selection from clipboard (if we are supposed to) and primary.
-      ;; So return the first one that has changed
-      ;; (which is the first non-null one).
-      ;;
-      ;; NOTE: There will be cases where more than one of these has
-      ;; changed and the new values differ.  This indicates that
-      ;; something like the following has happened since the last time
-      ;; we looked at the selections: Application X set all the
-      ;; selections, then Application Y set only one of them.
-      ;; In this case since we don't have
-      ;; timestamps there is no way to know what the 'correct' value to
-      ;; return is.  The nice thing to do would be to tell the user we
-      ;; saw multiple possible selections and ask the user which was the
-      ;; one they wanted.
-      (or clip-text primary-text)
-      )))
+  (let (clip-text primary-text)
+    (when x-select-enable-clipboard
+      (setq clip-text (x-selection-value-internal 'CLIPBOARD))
+      (if (string= clip-text "") (setq clip-text nil))
+
+      ;; Check the CLIPBOARD selection for 'newness', is it different
+      ;; from what we remembered them to be last time we did a
+      ;; cut/paste operation.
+      (setq clip-text
+            (cond ;; check clipboard
+             ((or (not clip-text) (string= clip-text ""))
+              (setq x-last-selected-text-clipboard nil))
+             ((eq      clip-text x-last-selected-text-clipboard) nil)
+             ((string= clip-text x-last-selected-text-clipboard)
+              ;; Record the newer string,
+              ;; so subsequent calls can use the `eq' test.
+              (setq x-last-selected-text-clipboard clip-text)
+              nil)
+             (t (setq x-last-selected-text-clipboard clip-text)))))
+
+    (when x-select-enable-primary
+      (setq primary-text (x-selection-value-internal 'PRIMARY))
+      ;; Check the PRIMARY selection for 'newness', is it different
+      ;; from what we remembered them to be last time we did a
+      ;; cut/paste operation.
+      (setq primary-text
+            (cond ;; check primary selection
+             ((or (not primary-text) (string= primary-text ""))
+              (setq x-last-selected-text-primary nil))
+             ((eq      primary-text x-last-selected-text-primary) nil)
+             ((string= primary-text x-last-selected-text-primary)
+              ;; Record the newer string,
+              ;; so subsequent calls can use the `eq' test.
+              (setq x-last-selected-text-primary primary-text)
+              nil)
+             (t
+              (setq x-last-selected-text-primary primary-text)))))
+
+    ;; As we have done one selection, clear this now.
+    (setq next-selection-coding-system nil)
+
+    ;; At this point we have recorded the current values for the
+    ;; selection from clipboard (if we are supposed to) and primary.
+    ;; So return the first one that has changed
+    ;; (which is the first non-null one).
+    ;;
+    ;; NOTE: There will be cases where more than one of these has
+    ;; changed and the new values differ.  This indicates that
+    ;; something like the following has happened since the last time
+    ;; we looked at the selections: Application X set all the
+    ;; selections, then Application Y set only one of them.
+    ;; In this case since we don't have
+    ;; timestamps there is no way to know what the 'correct' value to
+    ;; return is.  The nice thing to do would be to tell the user we
+    ;; saw multiple possible selections and ask the user which was the
+    ;; one they wanted.
+    (or clip-text primary-text)
+    ))
 
 (define-obsolete-function-alias 'x-cut-buffer-or-selection-value
   'x-selection-value "24.1")
 
 ;; Arrange for the kill and yank functions to set and check the clipboard.
-(setq interprogram-paste-function 'x-selection-value)
 
 (defun x-clipboard-yank ()
   "Insert the clipboard contents, or the last stretch of killed text."