[vte/wip/rishi/container-escape-sequence] Support tracking the active container inside the terminal, if any

[Debarshi Ray <debarshir src gnome org>]

commit 392f0d9d689d89d060bc2ae39238b6eda9cdf293
Author: Debarshi Ray <debarshir gnome org>
Date:   Mon Jun 10 20:30:18 2019 +0200

    Support tracking the active container inside the terminal, if any
    
    https://gitlab.freedesktop.org/terminal-wg/specifications/issues/17

 src/marshal.list      |  1 +
 src/vte/vteterminal.h |  5 +++-
 src/vtegtk.cc         | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++
 src/vtegtk.hh         |  4 +++
 src/vteinternal.hh    |  9 +++++++
 src/vteseq.cc         | 45 ++++++++++++++++++++++++++++++++-
 6 files changed, 131 insertions(+), 2 deletions(-)
---
diff --git a/src/marshal.list b/src/marshal.list
index 241128c3..4412cf3d 100644
--- a/src/marshal.list
+++ b/src/marshal.list
@@ -1,3 +1,4 @@
 VOID:STRING,BOXED
+VOID:STRING,STRING
 VOID:STRING,UINT
 VOID:UINT,UINT
diff --git a/src/vte/vteterminal.h b/src/vte/vteterminal.h
index db82d9e4..5bac43d5 100644
--- a/src/vte/vteterminal.h
+++ b/src/vte/vteterminal.h
@@ -104,8 +104,11 @@ struct _VteTerminalClass {
 
        void (*bell)(VteTerminal* terminal);
 
+       void (*current_container_popped)(VteTerminal *terminal);
+       void (*current_container_pushed)(VteTerminal *terminal, const gchar *name, const gchar *runtime);
+
         /* Padding for future expansion. */
-        gpointer padding[16];
+        gpointer padding[14];
 
         VteTerminalClassPrivate *priv;
 };
diff --git a/src/vtegtk.cc b/src/vtegtk.cc
index aab8e20d..7b4ae2ae 100644
--- a/src/vtegtk.cc
+++ b/src/vtegtk.cc
@@ -846,6 +846,54 @@ vte_terminal_class_init(VteTerminalClass *klass)
                                    G_OBJECT_CLASS_TYPE(klass),
                                    g_cclosure_marshal_VOID__VOIDv);
 
+        /**
+         * VteTerminal::current-container-popped:
+         * @vteterminal: the object which received the signal
+         *
+         * Emitted when leaving the current container being used
+         * inside the terminal. There must have been a matching
+         * #VteTerminal::current-container-pushed signal when this
+         * container was entered.
+         */
+        signals[SIGNAL_CURRENT_CONTAINER_POPPED] =
+                g_signal_new(I_("current-container-popped"),
+                             G_OBJECT_CLASS_TYPE(klass),
+                             G_SIGNAL_RUN_LAST,
+                             G_STRUCT_OFFSET(VteTerminalClass, current_container_popped),
+                             NULL,
+                             NULL,
+                             g_cclosure_marshal_VOID__VOID,
+                             G_TYPE_NONE, 0);
+        g_signal_set_va_marshaller(signals[SIGNAL_CURRENT_CONTAINER_POPPED],
+                                   G_OBJECT_CLASS_TYPE(klass),
+                                   g_cclosure_marshal_VOID__VOIDv);
+
+        /**
+         * VteTerminal::current-container-pushed:
+         * @vteterminal: the object which received the signal
+         * @name: the name of the new container
+         * @runtime: the name of the runtime toolset used to set up
+         * the current container
+         *
+         * Emitted when spawning a child process inside a new
+         * container. There should be a matching
+         * #VteTerminal::current-container-popped signal when this
+         * process exits.
+         */
+        signals[SIGNAL_CURRENT_CONTAINER_PUSHED] =
+                g_signal_new(I_("current-container-pushed"),
+                             G_OBJECT_CLASS_TYPE(klass),
+                             G_SIGNAL_RUN_LAST,
+                             G_STRUCT_OFFSET(VteTerminalClass, current_container_pushed),
+                             NULL,
+                             NULL,
+                             _vte_marshal_VOID__STRING_STRING,
+                             G_TYPE_NONE,
+                             2, G_TYPE_STRING, G_TYPE_STRING);
+        g_signal_set_va_marshaller(signals[SIGNAL_CURRENT_CONTAINER_PUSHED],
+                                   G_OBJECT_CLASS_TYPE(klass),
+                                   _vte_marshal_VOID__STRING_STRINGv);
+
         /**
          * VteTerminal::current-directory-uri-changed:
          * @vteterminal: the object which received the signal
@@ -1698,6 +1746,27 @@ vte_terminal_class_init(VteTerminalClass *klass)
                                      NULL,
                                      (GParamFlags) (G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | 
G_PARAM_EXPLICIT_NOTIFY));
 
+        /**
+         * VteTerminal:current-container-name:
+         *
+         * The name of the current container, or %NULL if unset.
+         */
+        pspecs[PROP_CURRENT_CONTAINER_NAME] =
+                g_param_spec_string ("current-container-name", NULL, NULL,
+                                     NULL,
+                                     (GParamFlags) (G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | 
G_PARAM_EXPLICIT_NOTIFY));
+
+        /**
+         * VteTerminal:current-container-runtime:
+         *
+         * The name of the runtime toolset used to set up the current
+         * container, or %NULL if unset.
+         */
+        pspecs[PROP_CURRENT_CONTAINER_RUNTIME] =
+                g_param_spec_string ("current-container-runtime", NULL, NULL,
+                                     NULL,
+                                     (GParamFlags) (G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | 
G_PARAM_EXPLICIT_NOTIFY));
+
         /**
          * VteTerminal:current-directory-uri:
          *
diff --git a/src/vtegtk.hh b/src/vtegtk.hh
index c49754ef..f31c07b9 100644
--- a/src/vtegtk.hh
+++ b/src/vtegtk.hh
@@ -32,6 +32,8 @@ enum {
         SIGNAL_COMMIT,
         SIGNAL_CONTENTS_CHANGED,
         SIGNAL_COPY_CLIPBOARD,
+        SIGNAL_CURRENT_CONTAINER_POPPED,
+        SIGNAL_CURRENT_CONTAINER_PUSHED,
         SIGNAL_CURRENT_DIRECTORY_URI_CHANGED,
         SIGNAL_CURRENT_FILE_URI_CHANGED,
         SIGNAL_CURSOR_MOVED,
@@ -73,6 +75,8 @@ enum {
         PROP_CJK_AMBIGUOUS_WIDTH,
         PROP_CURSOR_BLINK_MODE,
         PROP_CURSOR_SHAPE,
+        PROP_CURRENT_CONTAINER_NAME,
+        PROP_CURRENT_CONTAINER_RUNTIME,
         PROP_CURRENT_DIRECTORY_URI,
         PROP_CURRENT_FILE_URI,
         PROP_DELETE_BINDING,
diff --git a/src/vteinternal.hh b/src/vteinternal.hh
index f321105e..5bb9bbd2 100644
--- a/src/vteinternal.hh
+++ b/src/vteinternal.hh
@@ -40,7 +40,9 @@
 
 #include <list>
 #include <queue>
+#include <stack>
 #include <string>
+#include <utility>
 #include <vector>
 
 typedef enum {
@@ -555,6 +557,10 @@ public:
         gboolean m_cursor_moved_pending;
         gboolean m_contents_changed_pending;
 
+        bool m_containers_popped{false};
+        bool m_containers_pushed{false};
+        std::stack<std::pair<std::string, std::string>> m_containers;
+
         std::string m_window_title{};
         std::string m_current_directory_uri{};
         std::string m_current_file_uri{};
@@ -1286,6 +1292,9 @@ public:
                              int osc) noexcept;
 
         /* OSC handlers */
+        void handle_urxvt_extension(vte::parser::Sequence const& seq,
+                                    vte::parser::StringTokeniser::const_iterator& token,
+                                    vte::parser::StringTokeniser::const_iterator const& endtoken) noexcept;
         void set_color(vte::parser::Sequence const& seq,
                        vte::parser::StringTokeniser::const_iterator& token,
                        vte::parser::StringTokeniser::const_iterator const& endtoken,
diff --git a/src/vteseq.cc b/src/vteseq.cc
index d596d8b9..fe9170f2 100644
--- a/src/vteseq.cc
+++ b/src/vteseq.cc
@@ -1334,6 +1334,46 @@ Terminal::delete_lines(vte::grid::row_t param)
         m_text_deleted_flag = TRUE;
 }
 
+void
+Terminal::handle_urxvt_extension(vte::parser::Sequence const& seq,
+                                 vte::parser::StringTokeniser::const_iterator& token,
+                                 vte::parser::StringTokeniser::const_iterator const& endtoken) noexcept
+{
+        if (token == endtoken)
+                return;
+
+        if (*token == "container") {
+                ++token;
+
+                if (token == endtoken)
+                        return;
+
+                const std::string sub_command = *token;
+                ++token;
+
+                if (sub_command == "pop") {
+                        if (!m_containers.empty()) {
+                                m_containers.pop();
+                                m_containers_popped = true;
+                        }
+                } else if (sub_command == "push") {
+                        if (token == endtoken)
+                                return;
+
+                        const std::string name = *token;
+                        ++token;
+
+                        if (token == endtoken)
+                                return;
+
+                        const std::string runtime = *token;
+
+                        m_containers.emplace(name, runtime);
+                        m_containers_pushed = true;
+                }
+        }
+}
+
 bool
 Terminal::get_osc_color_index(int osc,
                                         int value,
@@ -6411,6 +6451,10 @@ Terminal::OSC(vte::parser::Sequence const& seq)
                 reset_color(VTE_HIGHLIGHT_FG, VTE_COLOR_SOURCE_ESCAPE);
                 break;
 
+        case VTE_OSC_URXVT_EXTENSION:
+                handle_urxvt_extension(seq, it, cend);
+                break;
+
         case VTE_OSC_XTERM_SET_ICON_TITLE:
         case VTE_OSC_XTERM_SET_XPROPERTY:
         case VTE_OSC_XTERM_SET_COLOR_MOUSE_CURSOR_FG:
@@ -6451,7 +6495,6 @@ Terminal::OSC(vte::parser::Sequence const& seq)
         case VTE_OSC_URXVT_SET_FONT_BOLD_ITALIC:
         case VTE_OSC_URXVT_VIEW_UP:
         case VTE_OSC_URXVT_VIEW_DOWN:
-        case VTE_OSC_URXVT_EXTENSION:
         case VTE_OSC_YF_RQGWR:
         default:
                 break;