[vte] terminal: Use smart pointer

[Christian Persch <chpe src gnome org>]

commit 60c0c3423c43fa1f64d1c50452197db43e51bbe6
Author: Christian Persch <chpe src gnome org>
Date:   Thu Nov 21 20:01:30 2019 +0100

    terminal: Use smart pointer

 src/vte.cc         | 22 +++++++---------------
 src/vteinternal.hh |  5 +++--
 src/widget.cc      | 15 ++++++++-------
 3 files changed, 18 insertions(+), 24 deletions(-)
---
diff --git a/src/vte.cc b/src/vte.cc
index 6879e0f2..138cd553 100644
--- a/src/vte.cc
+++ b/src/vte.cc
@@ -3311,15 +3311,10 @@ Terminal::watch_child (pid_t child_pid)
 void
 Terminal::im_reset()
 {
-        m_real_widget->im_reset();
-
-        m_im_preedit.clear();
-        m_im_preedit.shrink_to_fit();
+        if (widget())
+                widget()->im_reset();
 
-        if (m_im_preedit_attrs) {
-                pango_attr_list_unref(m_im_preedit_attrs);
-                m_im_preedit_attrs = nullptr;
-        }
+        im_preedit_reset();
 }
 
 void
@@ -4342,16 +4337,13 @@ Terminal::im_preedit_reset() noexcept
         m_im_preedit.clear();
         m_im_preedit.shrink_to_fit();
         m_im_preedit_cursor = 0;
-        if (m_im_preedit_attrs != nullptr) {
-                pango_attr_list_unref(m_im_preedit_attrs);
-                m_im_preedit_attrs = nullptr;
-        }
+        m_im_preedit_attrs.reset();
 }
 
 void
 Terminal::im_preedit_changed(std::string_view const& str,
                              int cursorpos,
-                             PangoAttrList* attrs) noexcept
+                             pango_attr_list_unique_type&& attrs) noexcept
 {
        /* Queue the area where the current preedit string is being displayed
         * for repainting. */
@@ -4359,7 +4351,7 @@ Terminal::im_preedit_changed(std::string_view const& str,
 
         im_preedit_reset();
        m_im_preedit = str;
-        m_im_preedit_attrs = attrs;
+        m_im_preedit_attrs = std::move(attrs);
         m_im_preedit_cursor = cursorpos;
 
         /* Invalidate again with the new cursor position */
@@ -9304,7 +9296,7 @@ Terminal::paint_im_preedit_string()
                 }
                draw_cells_with_attributes(
                                                        items, len,
-                                                       m_im_preedit_attrs,
+                                                       m_im_preedit_attrs.get(),
                                                        TRUE,
                                                        width, height);
                preedit_cursor = m_im_preedit_cursor;
diff --git a/src/vteinternal.hh b/src/vteinternal.hh
index 9c49efdd..2d580f12 100644
--- a/src/vteinternal.hh
+++ b/src/vteinternal.hh
@@ -683,7 +683,8 @@ public:
        /* Input method support. */
         bool m_im_preedit_active;
         std::string m_im_preedit;
-        PangoAttrList *m_im_preedit_attrs;
+        using pango_attr_list_unique_type = std::unique_ptr<PangoAttrList, decltype(&pango_attr_list_unref)>;
+        pango_attr_list_unique_type m_im_preedit_attrs{nullptr, &pango_attr_list_unref};
         int m_im_preedit_cursor;
 
         #ifdef WITH_A11Y
@@ -985,7 +986,7 @@ public:
         void im_preedit_reset() noexcept;
         void im_preedit_changed(std::string_view const& str,
                                 int cursorpos,
-                                PangoAttrList* attrs) noexcept;
+                                pango_attr_list_unique_type&& attrs) noexcept;
         bool im_retrieve_surrounding();
         bool im_delete_surrounding(int offset,
                                    int n_chars);
diff --git a/src/widget.cc b/src/widget.cc
index 7aef2bf5..afc429e2 100644
--- a/src/widget.cc
+++ b/src/widget.cc
@@ -223,18 +223,19 @@ Widget::im_focus_out() noexcept
 void
 Widget::im_preedit_changed() noexcept
 {
-        char* str;
-       PangoAttrList* attrs;
-       int cursorpos;
+        char* str = nullptr;
+       PangoAttrList* attrs = nullptr;
+       int cursorpos = 0;
 
         gtk_im_context_get_preedit_string(m_im_context.get(), &str, &attrs, &cursorpos);
-        if (str == nullptr)
-                return;
-
         _vte_debug_print(VTE_DEBUG_EVENTS, "Input method pre-edit changed (%s,%d).\n",
                          str, cursorpos);
 
-        m_terminal->im_preedit_changed(str, cursorpos, attrs);
+        if (str != nullptr)
+                m_terminal->im_preedit_changed(str, cursorpos, {attrs, &pango_attr_list_unref});
+        else
+                pango_attr_list_unref(attrs);
+
         g_free(str);
 }