bug#40268: 27.0.60; [PATCH] Unify and improve gdb-mi source window display

[Yuan Fu <casouri@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 609 bytes --]

Before this change, stepping and other gdb command handlers use 'gud-display-line’ and 'gdb-goto-breakpoint' uses 'gdb-display-source-buffer'.  Now whenever gdb-mi code tries to open a source buffer, 'gdb-display-source-buffer’ is used.  Also, we simplify the logic in 'gdb-display-source-buffer’ and add a feature to limit the maximum number of source windows.

From a user’s perspective, this change solves two problems: 1. The behavior difference between jumping to break point and stepping (and other command) 2. Gdb-mi opening more windows than I wanted for displaying source files.

Yuan


[-- Attachment #2: source-window.patch --]
[-- Type: application/octet-stream, Size: 8675 bytes --]

From ad34237cdc7c06e7edfcb593e8c732c6a040a7cb Mon Sep 17 00:00:00 2001
From: Yuan Fu <casouri@gmail.com>
Date: Tue, 21 Jan 2020 16:23:57 -0500
Subject: [PATCH] Unify and improve gdb-mi source buffer display logic

Unify the behavior of source buffer display for gdb-mi.  Before this
change, stepping and other gdb command handlers use 'gud-display-line'
and 'gdb-goto-breakpoint' uses 'gdb-display-source-buffer'.  Now whenever
gdb-mi code tries to open a source buffer, 'gdb-display-source-buffer'
is used.  Also, we simplify the logic in 'gdb-display-source-buffer' and
add a feature to limit the maximum number of source windows.

* lisp/progmodes/gdb-mi.el (gdb-source-window): Remove variable,
changed to 'gdb-source-window-list'.
(gdb-source-window-list, gdb-max-source-window-count): New variable.
(gdb-display-source-buffer-action,
gdb-max-source-window-count): New custom variable.
(gdb-init-1, gdb-setup-windows, gdb-restore-windows):
Use 'gdb-source-window' rather than 'gdb-source-window-list'.
(gdb-display-source-buffer): Use new logic.
(gdb-goto-breakpoint): Remove 'display-buffer'
and don't set 'gdb-source-buffer' anymore.
* lisp/progmodes/gud.el (gud-display-line): Remove 'display-buffer'
and don't set 'gdb-source-buffer' anymore.
---
 lisp/progmodes/gdb-mi.el | 65 +++++++++++++++++++++++++++++-----------
 lisp/progmodes/gud.el    | 26 ++++++++--------
 2 files changed, 60 insertions(+), 31 deletions(-)

diff --git a/lisp/progmodes/gdb-mi.el b/lisp/progmodes/gdb-mi.el
index e4233dacaf..5f31a22f22 100644
--- a/lisp/progmodes/gdb-mi.el
+++ b/lisp/progmodes/gdb-mi.el
@@ -211,7 +211,9 @@ gdb-handler-list
 (defvar gdb-source-file-list nil
   "List of source files for the current executable.")
 (defvar gdb-first-done-or-error t)
-(defvar gdb-source-window nil)
+(defvar gdb-source-window-list nil
+  "List of windows used for displaying source files.
+Sorted in most recently visited first order.")
 (defvar gdb-inferior-status nil)
 (defvar gdb-continuation nil)
 (defvar gdb-supports-non-stop nil)
@@ -589,6 +591,21 @@ gdb-show-main
   :group 'gdb
   :version "22.1")
 
+(defcustom gdb-display-source-buffer-action nil
+  "`display-buffer' action used when GDB displaying a source buffer."
+  :type 'list
+  :group 'gdb
+  :version "28.1")
+
+(defcustom gdb-max-source-window-count 1
+  "Maximum number of source windows to use.
+Until there are such number of source windows on screen, GDB
+tries to open a new window when visiting a new source file; if
+there are, GDB will start to reuse existing source windows."
+  :type 'number
+  :grou 'gdb
+  :version "28.1")
+
 (defvar gdbmi-debug-mode nil
   "When non-nil, print the messages sent/received from GDB/MI in *Messages*.")
 
@@ -922,7 +939,7 @@ gdb-init-1
 	gdb-first-done-or-error t
 	gdb-buffer-fringe-width (car (window-fringes))
 	gdb-debug-log nil
-	gdb-source-window nil
+	gdb-source-window-list nil
 	gdb-inferior-status nil
 	gdb-continuation nil
         gdb-buf-publisher '()
@@ -2002,17 +2019,31 @@ gdb-show-stop-p
 ;; GDB frame (after up, down etc).  If no GDB frame is visible but the last
 ;; visited breakpoint is, use that window.
 (defun gdb-display-source-buffer (buffer)
-  (let* ((last-window (if gud-last-last-frame
-                          (get-buffer-window
-                           (gud-find-file (car gud-last-last-frame)))))
-	 (source-window (or last-window
-			    (if (and gdb-source-window
-				     (window-live-p gdb-source-window))
-				gdb-source-window))))
-    (when source-window
-      (setq gdb-source-window source-window)
-      (set-window-buffer source-window buffer))
-    source-window))
+  "Find a window to display BUFFER.
+Always find a window to display buffer, and return it."
+  ;; This function doesn't take care of setting up source window(s) at startup,
+  ;; that's handled by `gdb-setup-windows' (if `gdb-many-windows' is non-nil).
+  ;; If `buffer' is already shown in a window, use that window.
+  (or (get-buffer-window buffer)
+      (progn
+        ;; First, update the window list.
+        (setq gdb-source-window-list
+              (cl-remove-if-not #'window-live-p
+                                gdb-source-window-list))
+        ;; Should we create a new window or reuse one?
+        (if (> gdb-max-source-window-count
+               (length gdb-source-window-list))
+            ;; Create a new window, push it to window list and return it.
+            (car (push (display-buffer buffer gdb-display-source-buffer-action)
+                       gdb-source-window-list))
+          ;; Reuse a window, we use the oldest window and put that to
+          ;; the front of the window list.
+          (let ((last-win (car (last gdb-source-window-list)))
+                (rest (butlast gdb-source-window-list)))
+            (set-window-buffer last-win buffer)
+            (setq gdb-source-window-list
+                  (cons last-win rest))
+            last-win)))))
 
 
 (defun gdbmi-start-with (str offset match)
@@ -3981,9 +4012,7 @@ gdb-goto-breakpoint
               (let* ((buffer (find-file-noselect
                               (if (file-exists-p file) file
                                 (cdr (assoc bptno gdb-location-alist)))))
-                     (window (or (gdb-display-source-buffer buffer)
-                                 (display-buffer buffer))))
-                (setq gdb-source-window window)
+                     (window (gdb-display-source-buffer buffer)))
                 (with-current-buffer buffer
                   (goto-char (point-min))
                   (forward-line (1- (string-to-number line)))
@@ -4597,7 +4626,7 @@ gdb-setup-windows
          ;; Put buffer list in window if we
          ;; can't find a source file.
          (list-buffers-noselect))))
-    (setq gdb-source-window (selected-window))
+    (setq gdb-source-window-list (list (selected-window)))
     (let ((win4 (split-window-right)))
       (gdb-set-window-buffer
        (gdb-get-buffer-create 'gdb-inferior-io) nil win4))
@@ -4639,7 +4668,7 @@ gdb-restore-windows
          (if gud-last-last-frame
              (gud-find-file (car gud-last-last-frame))
            (gud-find-file gdb-main-file)))
-        (setq gdb-source-window win)))))
+        (setq gdb-source-window-list (list win))))))
 
 ;; Called from `gud-sentinel' in gud.el:
 (defun gdb-reset ()
diff --git a/lisp/progmodes/gud.el b/lisp/progmodes/gud.el
index 567f452b93..dda7fd6ef0 100644
--- a/lisp/progmodes/gud.el
+++ b/lisp/progmodes/gud.el
@@ -2826,9 +2826,11 @@ gud-display-line
 	 (buffer
 	  (with-current-buffer gud-comint-buffer
 	    (gud-find-file true-file)))
-	 (window (and buffer
-		      (or (get-buffer-window buffer)
-			  (display-buffer buffer '(nil (inhibit-same-window . t))))))
+	 (window (when buffer (if (eq gud-minor-mode 'gdb-mi)
+                                  (gdb-display-source-buffer buffer)
+                                ;; Gud still has the old behavior.
+                                (or (get-buffer-window buffer)
+                                    (display-buffer buffer '(nil (inhibit-same-window . t)))))))
 	 (pos))
     (when buffer
       (with-current-buffer buffer
@@ -2858,9 +2860,7 @@ gud-display-line
 	       (widen)
 	       (goto-char pos))))
       (when window
-	(set-window-point window gud-overlay-arrow-position)
-	(if (eq gud-minor-mode 'gdbmi)
-	    (setq gdb-source-window window))))))
+	(set-window-point window gud-overlay-arrow-position)))))
 
 ;; The gud-call function must do the right thing whether its invoking
 ;; keystroke is from the GUD buffer itself (via major-mode binding)
@@ -2908,14 +2908,14 @@ gud-format-command
 	  (setq subst
                 (gud-find-class
                  (if insource
-                      (buffer-file-name)
-                    (car frame))
+                     (buffer-file-name)
+                   (car frame))
                  (if insource
-                      (save-restriction
-                        (widen)
-                        (+ (count-lines (point-min) (point))
-                           (if (bolp) 1 0)))
-                    (cdr frame)))))
+                     (save-restriction
+                       (widen)
+                       (+ (count-lines (point-min) (point))
+                          (if (bolp) 1 0)))
+                   (cdr frame)))))
 	 ((eq key ?p)
 	  (setq subst (if arg (int-to-string arg)))))
 	(setq result (concat result (match-string 1 str) subst)))
-- 
2.25.1


[-- Attachment #3: Type: text/plain, Size: 11199 bytes --]




In GNU Emacs 27.0.60 (build 1, x86_64-apple-darwin19.3.0, NS appkit-1894.30 Version 10.15.3 (Build 19D76))
of 2020-02-25 built on missSilver
Repository revision: f27187f963e9e36435b508e29256e048799e0ff2
Repository branch: emacs-27
Windowing system distributor 'Apple', version 10.3.1894
System Description:  Mac OS X 10.15.4

Recent messages:
Checking 34 files in /Users/yuan/emacs/lisp/emulation...
Checking 180 files in /Users/yuan/emacs/lisp/emacs-lisp...
Checking 24 files in /Users/yuan/emacs/lisp/cedet...
Checking 59 files in /Users/yuan/emacs/lisp/calendar...
Checking 87 files in /Users/yuan/emacs/lisp/calc...
Checking 113 files in /Users/yuan/emacs/lisp/obsolete...
Checking for load-path shadows...done
Auto-saving...
Buffer *unsent mail to bug-gnu-emacs@gnu.org* modified; kill anyway? (y or n) y
C-c C-c is undefined

Configured using:
'configure --with-modules --with-pdumper=yes
--oldincludedir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/libxml2/'

Configured features:
RSVG GLIB NOTIFY KQUEUE ACL GNUTLS LIBXML2 ZLIB TOOLKIT_SCROLL_BARS XIM
NS MODULES THREADS PDUMPER LCMS2

Important settings:
  value of $LC_CTYPE: UTF-8
  value of $LANG: en_CN.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Shell-script

Minor modes in effect:
  global-semanticdb-minor-mode: t
  global-semantic-idle-scheduler-mode: t
  semantic-mode: t
  sh-electric-here-document-mode: t
  global-magit-file-mode: t
  magit-file-mode: t
  global-git-commit-mode: t
  async-bytecomp-package-mode: t
  shell-dirtrack-mode: t
  diff-hl-mode: t
  color-outline-mode: t
  hi-lock-mode: t
  desktop-save-mode: t
  helpful-html-manual-mode: t
  yas-global-mode: t
  yas-minor-mode: t
  form-feed-mode: t
  minibuffer-electric-default-mode: t
  flycheck-mode: t
  flyspell-mode: t
  minions-mode: t
  eyebrowse-mode: t
  savehist-mode: t
  global-hl-todo-mode: t
  hl-todo-mode: t
  global-highlight-parentheses-mode: t
  highlight-parentheses-mode: t
  rainbow-delimiters-mode: t
  global-undo-tree-mode: t
  undo-tree-mode: t
  electric-pair-mode: t
  winner-mode: t
  ivy-prescient-mode: t
  prescient-persist-mode: t
  recentf-mode: t
  which-key-mode: t
  general-override-mode: t
  outline-minor-mode: t
  counsel-mode: t
  ivy-mode: t
  company-mode: t
  override-global-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-quote-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  hs-minor-mode: t

Load-path shadows:
/Users/yuan/.emacs.d/ranch/winman/windman hides /Users/yuan/.emacs.d/ranch/windman/windman
/Users/yuan/.emacs.d/ranch/separedit/cask-bootstrap hides /Users/yuan/.emacs.d/ranch/comment-edit/cask-bootstrap
/Users/yuan/.emacs.d/ranch/esup/esup-child hides /Users/yuan/.emacs.d/package/esup-20200120.740/esup-child
/Users/yuan/.emacs.d/ranch/esup/esup hides /Users/yuan/.emacs.d/package/esup-20200120.740/esup
/Users/yuan/.emacs.d/ranch/julia-mode/julia-mode hides /Users/yuan/.emacs.d/package/julia-mode-20190813.1326/julia-mode
/Users/yuan/.emacs.d/ranch/julia-mode/julia-latexsubs hides /Users/yuan/.emacs.d/package/julia-mode-20190813.1326/julia-latexsubs
/Users/yuan/.emacs.d/ranch/matlab-emacs/mlint hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/mlint
/Users/yuan/.emacs.d/ranch/matlab-emacs/company-matlab-shell hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/company-matlab-shell
/Users/yuan/.emacs.d/ranch/matlab-emacs/linemark hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/linemark
/Users/yuan/.emacs.d/ranch/matlab-emacs/semanticdb-matlab hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/semanticdb-matlab
/Users/yuan/.emacs.d/ranch/matlab-emacs/semantic-matlab hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/semantic-matlab
/Users/yuan/.emacs.d/ranch/matlab-emacs/srecode-matlab hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/srecode-matlab
/Users/yuan/.emacs.d/ranch/matlab-emacs/matlab hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/matlab
/Users/yuan/.emacs.d/ranch/matlab-emacs/cedet-matlab hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/cedet-matlab
/Users/yuan/.emacs.d/ranch/matlab-emacs/tlc hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/tlc
/Users/yuan/.emacs.d/ranch/matlab-emacs/matlab-publish hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/matlab-publish
/Users/yuan/.emacs.d/ranch/matlab-emacs/matlab-mode-pkg hides /Users/yuan/.emacs.d/package/matlab-mode-20180928.1526/matlab-mode-pkg
/Users/yuan/.emacs.d/package/faceup-20170925.1946/faceup hides /Users/yuan/emacs/lisp/emacs-lisp/faceup

Features:
(shadow sort mail-extr emacsbug sendmail face-remap rfc1345 quail
semantic/tag-write semantic/tag-file semantic/bovine/c hideif
semantic/bovine/c-by semantic/lex-spp semantic/bovine/gcc
semantic/analyze/refs semantic/db-file data-debug cedet-files
semantic/bovine/scm semantic/decorate/include semantic/db-find
semantic/db-ref semantic/decorate/mode semantic/decorate pulse
semantic/dep semantic/bovine/scm-by semantic/bovine semantic/db-mode
semantic/idle semantic/analyze semantic/sort semantic/scope
semantic/analyze/fcn semantic/db eieio-base semantic/format ezimage
semantic/tag-ls semantic/find semantic/ctxt semantic/util-modes
semantic/util semantic semantic/tag semantic/lex semantic/fw mode-local
cedet cc-mode-expansions cc-mode cc-fonts cc-guess cc-menus cc-cmds
cc-styles cc-align cc-engine cc-vars cc-defs ls-lisp ess-custom apropos
sh-script smie executable geiser-mode geiser-xref geiser-compile
geiser-debug geiser-gambit geiser-chibi geiser-mit geiser-chez
geiser-chicken geiser-racket geiser-guile ghelp-geiser console-buffer
geiser geiser-repl geiser-image geiser-company geiser-doc geiser-menu
geiser-edit geiser-completion geiser-autodoc geiser-eval
geiser-connection tq geiser-syntax geiser-log geiser-popup view
geiser-impl geiser-custom geiser-base scheme vc-mtn vc-hg bug-reference
magit-patch-changelog magit-patch magit-bookmark magit-submodule
magit-obsolete magit-blame magit-stash magit-reflog magit-bisect
magit-push magit-pull magit-fetch magit-clone magit-remote magit-commit
magit-sequence magit-notes magit-worktree magit-tag magit-merge
magit-branch magit-reset magit-files magit-refs magit-status magit
magit-repos magit-apply magit-wip magit-log which-func magit-diff
smerge-mode magit-core magit-autorevert autorevert magit-margin
magit-transient magit-process magit-mode transient git-commit magit-git
magit-section magit-utils crm log-edit pcvs-util add-log with-editor
async-bytecomp async shell misearch multi-isearch vc-git vc-bzr vc-src
vc-sccs vc-svn vc-cvs vc-rcs bookmark server cl-print gnutls mm-archive
message rfc822 mml mml-sec epa derived gnus-util rmail rmail-loaddefs
text-property-search mailabbrev gmm-utils mailheader mm-decode mm-bodies
mm-encode mail-utils network-stream url-http mail-parse rfc2231 rfc2047
rfc2045 mm-util ietf-drums mail-prsvr url-gw nsm rmc puny url-cache
url-auth url url-proxy url-privacy url-expand url-methods url-history
url-cookie url-domsuf mailcap epg epg-config hideshow diff-hl vc-dir vc
vc-dispatcher diff-mode color-outline hi-lock company-oddmuse
company-keywords company-etags etags fileloop generator company-gtags
company-dabbrev-code company-dabbrev company-files company-capf
company-cmake company-xcode company-clang company-semantic company-eclim
company-template company-bbdb desktop frameset trivial-copy ghelp
ghelp-eglot ghelp-helpful ghelp-builtin cus-edit centaur-tabs
centaur-tabs-interactive centaur-tabs-functions centaur-tabs-elements
powerline powerline-separators powerline-themes cus-start cus-load
luna-general-config pause utility transform flywrap yasnippet
sly-el-indent sly-cl-indent cl-indent cl all-the-icons
all-the-icons-faces data-material data-weathericons data-octicons
data-fileicons data-faicons data-alltheicons memoize form-feed
minibuf-eldef eglot array filenotify jsonrpc ert pp ewoc debug
flymake-proc flymake warnings url-util flycheck flyspell ispell outshine
outshine-org-cmds outorg isolate inline expand-region
text-mode-expansions the-org-mode-expansions er-basic-expansions
thingatpt expand-region-core expand-region-custom ws-butler minions
eyebrowse savehist buffer-move windmove hl-todo highlight-parentheses
rainbow-delimiters doom-cyberpunk-theme undo-tree diff
doom-one-light-theme elec-pair winner doom-themes doom-themes-base
windman aggressive-indent find-char ivy-prescient prescient recentf-ext
recentf tree-widget wid-edit which-key general helpful imenu trace
edebug backtrace info-look f dash-functional help-fns radix-tree
elisp-refs s loop dash org ob ob-tangle ob-ref ob-lob ob-table ob-exp
org-macro org-footnote org-src ob-comint org-pcomplete pcomplete
org-list org-faces org-entities time-date noutline outline org-version
ob-emacs-lisp ob-core ob-eval org-table ol org-keys org-compat advice
org-macs org-loaddefs format-spec find-func cal-menu calendar
cal-loaddefs counsel xdg xref project dired dired-loaddefs compile
comint ansi-color swiper cl-extra help-mode ivy delsel ring colir color
ivy-overlay company edmacro kmacro pcase use-package use-package-ensure
use-package-delight use-package-diminish use-package-bind-key bind-key
use-package-core finder-inf tex-site proof-site proof-autoloads info
cowboy package easymenu browse-url url-handlers url-parse auth-source
cl-seq eieio eieio-core cl-macs eieio-loaddefs password-cache json
subr-x map url-vars cl-loaddefs cl-lib lunary lunary-ui easy-mmode
luna-f rx seq byte-opt gv bytecomp byte-compile cconv tooltip eldoc
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel term/ns-win
ns-win ucs-normalize mule-util term/common-win tool-bar dnd fontset
image regexp-opt fringe tabulated-list replace newcomment text-mode
elisp-mode lisp-mode prog-mode register page tab-bar menu-bar
rfn-eshadow isearch timer select scroll-bar mouse jit-lock font-lock
syntax facemenu font-core term/tty-colors frame minibuffer cl-generic
cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese composite charscript charprop
case-table epa-hook jka-cmpr-hook help simple abbrev obarray
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote threads kqueue cocoa ns
lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 489882 97798)
(symbols 48 40858 45)
(strings 32 193314 9271)
(string-bytes 1 4564854)
(vectors 16 58289)
(vector-slots 8 1900639 84204)
(floats 8 468 326)
(intervals 56 7219 1188)
(buffers 1000 40))