From 8087250476b7cc6c8c6b1dace2bb89815682504e Mon Sep 17 00:00:00 2001
From: Matthias Clasen <mclasen@redhat.com>
Date: Wed, 7 Jul 2021 17:03:11 -0400
Subject: [PATCH] imcontext: Replace the builtin sequences

When we find a Compose file, replace the builtin
sequences with the table we found. This matches the
semantics described in Compose(5), and makes it possible
to drop unwanted sequences from the builtin table.

It is slight change of behavior for users with existing
Compose files. To match the previous behavior, you have
to add

include "%L"

to your Compose file, to keep the builtin sequences in
addition to your own.
---
 gtk/gtkimcontextsimple.c | 37 ++++++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 13 deletions(-)

diff --git a/gtk/gtkimcontextsimple.c b/gtk/gtkimcontextsimple.c
index 4e160ab048..078ed6f612 100644
--- a/gtk/gtkimcontextsimple.c
+++ b/gtk/gtkimcontextsimple.c
@@ -40,15 +40,15 @@
  *
  * `GtkIMContextSimple` is an input method supporting table-based input methods.
  *
- * `GtkIMContextSimple` has a built-in table of compose sequences that is
- * derived from the X11 Compose files.
- *
- * `GtkIMContextSimple` reads additional compose sequences from the first of the
+ * `GtkIMContextSimple` reads compose sequences from the first of the
  * following files that is found: ~/.config/gtk-4.0/Compose, ~/.XCompose,
  * /usr/share/X11/locale/$locale/Compose (for locales that have a nontrivial
  * Compose file). The syntax of these files is described in the Compose(5)
  * manual page.
  *
+ * If none of these files is found, `GtkIMContextSimple` uses a built-in table
+ * of compose sequences that is derived from the X11 Compose files.
+ *
  * ## Unicode characters
  *
  * `GtkIMContextSimple` also supports numeric entry of Unicode characters
@@ -88,6 +88,7 @@ const GtkComposeTableCompact gtk_compose_table_compact = {
 
 G_LOCK_DEFINE_STATIC (global_tables);
 static GSList *global_tables;
+static gboolean omit_builtin_sequences;
 
 static const guint16 gtk_compose_ignore[] = {
   0, /* Yes, XKB will send us key press events with NoSymbol :( */
@@ -173,7 +174,8 @@ gtk_compose_table_find (gconstpointer data1,
 }
 
 static void
-add_compose_table_from_file (const char *compose_file)
+add_compose_table_from_file (const char *compose_file,
+                             gboolean    replace_builtin)
 {
   guint hash;
 
@@ -187,7 +189,11 @@ add_compose_table_from_file (const char *compose_file)
       table = gtk_compose_table_new_with_file (compose_file);
 
       if (table)
-        global_tables = g_slist_prepend (global_tables, table);
+        {
+          global_tables = g_slist_prepend (global_tables, table);
+          if (replace_builtin)
+            omit_builtin_sequences = TRUE;
+        }
     }
 
   G_UNLOCK (global_tables);
@@ -231,7 +237,7 @@ gtk_im_context_simple_init_compose_table (void)
   path = g_build_filename (g_get_user_config_dir (), "gtk-4.0", "Compose", NULL);
   if (g_file_test (path, G_FILE_TEST_EXISTS))
     {
-      add_compose_table_from_file (path);
+      add_compose_table_from_file (path, TRUE);
       g_free (path);
       return;
     }
@@ -244,7 +250,7 @@ gtk_im_context_simple_init_compose_table (void)
   path = g_build_filename (home, ".XCompose", NULL);
   if (g_file_test (path, G_FILE_TEST_EXISTS))
     {
-      add_compose_table_from_file (path);
+      add_compose_table_from_file (path, TRUE);
       g_free (path);
       return;
     }
@@ -288,7 +294,9 @@ gtk_im_context_simple_init_compose_table (void)
   g_strfreev (langs);
 
   if (path != NULL)
-    add_compose_table_from_file (path);
+    {
+      add_compose_table_from_file (path, TRUE);
+    }
 
   g_free (path);
 }
@@ -1066,7 +1074,10 @@ gtk_im_context_simple_filter_keypress (GtkIMContext *context,
       if (success)
         return TRUE;
 
-      if (gtk_compose_table_compact_check (&gtk_compose_table_compact,
+      G_LOCK (global_tables);
+
+      if (!omit_builtin_sequences &&
+          gtk_compose_table_compact_check (&gtk_compose_table_compact,
                                            priv->compose_buffer, n_compose,
                                            &compose_finish, &compose_match,
                                            &output_char))
@@ -1096,6 +1107,8 @@ gtk_im_context_simple_filter_keypress (GtkIMContext *context,
           return TRUE;
         }
 
+      G_UNLOCK (global_tables);
+
       if (gtk_check_algorithmically (priv->compose_buffer, n_compose, &output_char))
         {
           if (!priv->in_compose_sequence)
@@ -1255,8 +1268,6 @@ gtk_im_context_simple_add_table (GtkIMContextSimple *context_simple,
 				 int                 max_seq_len,
 				 int                 n_seqs)
 {
-  GtkComposeTable *table;
-
   g_return_if_fail (GTK_IS_IM_CONTEXT_SIMPLE (context_simple));
 
   add_compose_table_from_data (data, max_seq_len, n_seqs);
@@ -1275,5 +1286,5 @@ gtk_im_context_simple_add_compose_file (GtkIMContextSimple *context_simple,
 {
   g_return_if_fail (GTK_IS_IM_CONTEXT_SIMPLE (context_simple));
 
-  add_compose_table_from_file (compose_file);
+  add_compose_table_from_file (compose_file, FALSE);
 }