From a88e8d1a31ff001b2d84c80b63b32b794f569051 Mon Sep 17 00:00:00 2001
From: Debarshi Ray <debarshir@gnome.org>
Date: Sun, 26 Nov 2023 18:30:19 -0800
Subject: [PATCH 6/9] Support precmd notifications from an interactive shell

Add sequences
  OSC 777 ; precmd BEL
  OSC 777 ; precmd ST

that can be used from an interactive shell's precmd hook to notify the
terminal emulator that a first level prompt is about to be shown.
Examples of such hooks are Bash's PROMPT_COMMAND and Zsh's precmd.

The OSC 777 escape sequence is taken from Enlightenment's Terminology:
https://phab.enlightenment.org/T1765

https://bugzilla.gnome.org/show_bug.cgi?id=711059
https://bugzilla.gnome.org/show_bug.cgi?id=711060
---
 src/vte.cc            |  6 ++++++
 src/vte.sh.in         |  2 +-
 src/vte/vteterminal.h |  5 +----
 src/vtegtk.cc         | 18 ++++++++++++++++++
 src/vtegtk.hh         |  1 +
 src/vteinternal.hh    |  1 +
 src/vteseq.cc         |  4 +++-
 7 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/src/vte.cc b/src/vte.cc
index 49a3d8f3..14a259c2 100644
--- a/src/vte.cc
+++ b/src/vte.cc
@@ -10780,6 +10780,12 @@ Terminal::emit_pending_signals()
                                   "Emitting `shell-preexec'.\n");
                 g_signal_emit(freezer.get(), signals[SIGNAL_SHELL_PREEXEC], 0);
         }
+
+        if (m_pending_changes & vte::to_integral(PendingChanges::SHELL_PRECMD)) {
+                _vte_debug_print (VTE_DEBUG_SIGNALS,
+                                  "Emitting `shell-precmd'.\n");
+                g_signal_emit(freezer.get(), signals[SIGNAL_SHELL_PRECMD], 0);
+        }
 #endif
 
 	if (m_pending_changes & vte::to_integral(PendingChanges::TITLE)) {
diff --git a/src/vte.sh.in b/src/vte.sh.in
index fbbb1a03..22f1fd5c 100644
--- a/src/vte.sh.in
+++ b/src/vte.sh.in
@@ -38,7 +38,7 @@ __vte_prompt_command() {
   local pwd='~'
   [ "$PWD" != "$HOME" ] && pwd=${PWD/#$HOME\//\~\/}
   pwd="${pwd//[[:cntrl:]]}"
-  printf '\033]777;notify;Command completed;%s\033\\\033]0;%s@%s:%s\033\\' "${command}" "${USER}" "${HOSTNAME%%.*}" "${pwd}"
+  printf '\033]777;notify;Command completed;%s\033\\\033]777;precmd\033\\\033]0;%s@%s:%s\033\\' "${command}" "${USER}" "${HOSTNAME%%.*}" "${pwd}"
   __vte_osc7
 }
 
diff --git a/src/vte/vteterminal.h b/src/vte/vteterminal.h
index 29529020..aed105e9 100644
--- a/src/vte/vteterminal.h
+++ b/src/vte/vteterminal.h
@@ -115,11 +115,8 @@ struct _VteTerminalClass {
 
 #if _VTE_GTK == 3
         void (*notification_received)(VteTerminal* terminal, const gchar *summary, const gchar *body);
+        void (*shell_precmd)(VteTerminal* terminal);
         void (*shell_preexec)(VteTerminal* terminal);
-
-        /* Compatibility padding due to fedora patches intruding on our ABI */
-        /*< private >*/
-        gpointer _extra_padding[1];
 #endif /* _VTE_GTK == 3 */
 
         void (*setup_context_menu)(VteTerminal* terminal,
diff --git a/src/vtegtk.cc b/src/vtegtk.cc
index c4cf5537..79de4a1b 100644
--- a/src/vtegtk.cc
+++ b/src/vtegtk.cc
@@ -1347,6 +1347,7 @@ vte_terminal_class_init(VteTerminalClass *klass)
 	klass->char_size_changed = NULL;
 #if _VTE_GTK == 3
 	klass->notification_received = NULL;
+	klass->shell_precmd = NULL;
 	klass->shell_preexec = NULL;
 #endif
 	klass->window_title_changed = NULL;
@@ -1453,6 +1454,23 @@ vte_terminal_class_init(VteTerminalClass *klass)
                              G_TYPE_NONE,
                              2, G_TYPE_STRING, G_TYPE_STRING);
 
+        /**
+         * VteTerminal::shell-precmd:
+         * @vteterminal: the object which received the signal
+         *
+         * Emitted right before an interactive shell shows a
+         * first-level prompt.
+         */
+        signals[SIGNAL_SHELL_PRECMD] =
+                g_signal_new(I_("shell-precmd"),
+                             G_OBJECT_CLASS_TYPE(klass),
+                             G_SIGNAL_RUN_LAST,
+                             G_STRUCT_OFFSET(VteTerminalClass, shell_precmd),
+                             NULL,
+                             NULL,
+                             g_cclosure_marshal_VOID__VOID,
+                             G_TYPE_NONE, 0);
+
         /**
          * VteTerminal::shell-preexec:
          * @vteterminal: the object which received the signal
diff --git a/src/vtegtk.hh b/src/vtegtk.hh
index 4e400cd3..a1c3f3df 100644
--- a/src/vtegtk.hh
+++ b/src/vtegtk.hh
@@ -54,6 +54,7 @@ enum {
         SIGNAL_SELECTION_CHANGED,
         SIGNAL_SETUP_CONTEXT_MENU,
 #if _VTE_GTK == 3
+        SIGNAL_SHELL_PRECMD,
         SIGNAL_SHELL_PREEXEC,
         SIGNAL_NOTIFICATION_RECEIVED,
 #endif
diff --git a/src/vteinternal.hh b/src/vteinternal.hh
index 0479ae0e..05625f83 100644
--- a/src/vteinternal.hh
+++ b/src/vteinternal.hh
@@ -758,6 +758,7 @@ public:
 #if _VTE_GTK == 3
                 NOTIFICATION = 1u << 3,
                 SHELL_PREEXEC = 1u << 4,
+                SHELL_PRECMD = 1u << 5,
 #endif
         };
         unsigned m_pending_changes{0};
diff --git a/src/vteseq.cc b/src/vteseq.cc
index 92d1f857..44f13505 100644
--- a/src/vteseq.cc
+++ b/src/vteseq.cc
@@ -1326,7 +1326,9 @@ Terminal::handle_urxvt_extension(vte::parser::Sequence const& seq,
                 return;
         }
 
-        if (*token == "preexec") {
+        if (*token == "precmd") {
+                m_pending_changes |= vte::to_integral(PendingChanges::SHELL_PRECMD);
+        } else if (*token == "preexec") {
                 m_pending_changes |= vte::to_integral(PendingChanges::SHELL_PREEXEC);
         }
 }
-- 
2.43.0