Enable to modify the iBus keyboard layout without the root permission.

Update from the upstream. (BUILD=4220)
* Enabled to dynamically generate the entries of iBus engines.
* Enabled to modify the iBus keyboard layout without the root permission.

-----

After this change, the contents of /usr/share/ibus/component/mozc.xml is changed as follows.

Before
```
<component>
  <name>com.google.IBus.Mozc</name>
  <description>Mozc Component</description>
  <exec>/usr/lib/ibus-mozc/ibus-engine-mozc --ibus</exec>
  <version>0.0.0.0</version>
  <author>Google Inc.</author>
  <license>New BSD</license>
  <homepage>https://github.com/google/mozc</homepage>
  <textdomain>ibus-mozc</textdomain>
<engines>
<engine>
  <description>Mozc (Japanese Input Method)</description>
  <language>ja</language>
  <icon>/usr/share/ibus-mozc/product_icon.png</icon>
  <rank>80</rank>
  <icon_prop_key>InputMode</icon_prop_key>
  <symbol>&#x3042;</symbol>
  <setup>/usr/lib/mozc/mozc_tool --mode=config_dialog</setup>
  <name>mozc-jp</name>
  <longname>Mozc</longname>
  <layout>default</layout>
</engine>
</engines>
</component>
```

After
```
<component>
  <name>com.google.IBus.Mozc</name>
  <description>Mozc Component</description>
  <exec>/usr/lib/ibus-mozc/ibus-engine-mozc --ibus</exec>
  <version>0.0.0.0</version>
  <author>Google Inc.</author>
  <license>New BSD</license>
  <homepage>https://github.com/google/mozc</homepage>
  <textdomain>ibus-mozc</textdomain>
  <engines exec="/usr/lib/ibus-mozc/ibus-engine-mozc --xml" />
</component>

<!-- Settings of <engines> and <layout> are stored in ibus_config.textproto -->
<!-- under the user configuration directory, which is either of: -->
<!-- * $XDG_CONFIG_HOME/mozc/ibus_config.textproto -->
<!-- * $HOME/.config/mozc/ibus_config.textproto -->
<!-- * $HOME/.mozc/ibus_config.textproto -->
```

Then, `/usr/lib/ibus-mozc/ibus-engine-mozc --xml` returns the values of the <engine> tags.

If `ibus_config.textproto` exists under the user config directory.
(i.e. `~/.mozc/ibus_config.textproto` or `~/.config/mozc/ibus_config.textproto`)
Mozc uses the settings in the file. If `ibus_config.textproto` does not exist,
it is created with the default values.

So, the users do not need to modify `/usr/share/ibus/component/mozc.xml` directly.
This is the same mechanism with ibus-anthy.

This change will fix two issues.

* There was no way to use Kana layout for US keyboard. With this change,
  if the layout is us, Kana layout for US keyboard is used instead of JP keyboard.
* If multilingual layouts were selected, the keyboard layout for Mozc was not stable.
  For example, when US and FR keyboards were selected in addition to Mozc,
  Mozc's layout was not stable. This change enables to specify the static layout for Mozc.

src/data/version/mozc_version_template.bzl

@@ -33,7 +33,7 @@ MAJOR = 2
 MINOR = 26
 
 # Number to be increased. This value may be replaced by other tools.
-BUILD = 4219
+BUILD = 4220
 
 # Represent the platform and release channel.
 REVISION = 100

src/unix/ibus/BUILD

@@ -36,6 +36,7 @@ load(
     "py_binary_mozc",
     "select_mozc",
 )
+load("//tools/build_defs:stubs.bzl", "portable_proto_library")
 
 package(default_visibility = ["//:__subpackages__"])
 
@@ -50,33 +51,25 @@ py_binary_mozc(
     srcs = ["gen_mozc_xml.py"],
 )
 
-# This genrule uses pkg-config in gen_mozc_xml_main.
 genrule(
     name = "gen_mozc_xml",
     outs = ["mozc.xml"],
-    cmd = select_mozc(
-        default = "touch $@",  # This is stub.
-        linux = ("$(location :gen_mozc_xml_main) --branding=Mozc" +
-                 " --server_dir=" + MOZC_SERVER_DIRECTORY +
-                 " --ibus_mozc_path=" + IBUS_MOZC_PATH +
-                 " --ibus_mozc_icon_path=" + IBUS_MOZC_ICON_PATH +
-                 " > $@"),
-    ),
+    cmd = ("$(location :gen_mozc_xml_main) --branding=Mozc" +
+           " --server_dir=" + MOZC_SERVER_DIRECTORY +
+           " --ibus_mozc_path=" + IBUS_MOZC_PATH +
+           " --ibus_mozc_icon_path=" + IBUS_MOZC_ICON_PATH +
+           " > $@"),
     exec_tools = [":gen_mozc_xml_main"],
 )
 
-# This genrule uses pkg-config in gen_mozc_xml_main.
 genrule(
     name = "gen_main_h",
     outs = ["main.h"],
-    cmd = select_mozc(
-        default = "touch $@",  # This is stub.
-        linux = ("$(location :gen_mozc_xml_main) --branding=Mozc" +
-                 " --output_cpp" +
-                 " --ibus_mozc_path=" + IBUS_MOZC_PATH +
-                 " --ibus_mozc_icon_path=" + IBUS_MOZC_ICON_PATH +
-                 " > $@"),
-    ),
+    cmd = ("$(location :gen_mozc_xml_main) --branding=Mozc" +
+           " --output_cpp" +
+           " --ibus_mozc_path=" + IBUS_MOZC_PATH +
+           " --ibus_mozc_icon_path=" + IBUS_MOZC_ICON_PATH +
+           " > $@"),
     exec_tools = [":gen_mozc_xml_main"],
 )
 
@@ -169,8 +162,13 @@ cc_library_mozc(
             "surrounding_text_util.h",
         ],
     ),
+    defines = [
+        "ENABLE_GTK_RENDERER",
+        "MOZC_ENABLE_X11_SELECTION_MONITOR",
+    ],
     deps = [
         ":gtk_candidate_window_handler",
+        ":ibus_config",
         ":ibus_property_handler",
         ":ibus_utils",
         ":x11_selection_monitor",
@@ -180,6 +178,41 @@ cc_library_mozc(
     ],
 )
 
+proto_library(
+    name = "ibus_config_proto_full",
+    srcs = [
+        "ibus_config.proto",
+    ],
+)
+
+portable_proto_library(
+    name = "ibus_config_proto",
+    config_string = "allow_all: true",
+    header_outs = [
+        "ibus_config.pb.h",
+    ],
+    proto_deps = ["ibus_config_proto_full"],
+)
+
+cc_library_mozc(
+    name = "ibus_config",
+    srcs = ["ibus_config.cc"],
+    hdrs = [
+        "ibus_config.h",
+        ":gen_main_h",
+    ],
+    copts = ["-Wno-unused-variable"],
+    deps = [
+        ":ibus_config_proto",
+        "//base:file_stream",
+        "//base:file_util",
+        "//base:logging",
+        "//base:system_util",
+        "//base/protobuf:text_format",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
 cc_binary_mozc(
     name = "ibus_mozc",
     srcs = select_mozc(
@@ -191,9 +224,11 @@ cc_binary_mozc(
     ),
     data = [":gen_mozc_xml"],
     deps = [
+        ":ibus_config",
         ":ibus_mozc_lib",
         ":ibus_mozc_metadata",
         "//base",
+        "//base:flags",
         "//base:init_mozc",
     ],
 )

src/unix/ibus/gen_mozc_xml.py

@@ -40,7 +40,6 @@
 
 import optparse
 import os
-import subprocess
 import sys
 
 # Information to generate <component> part of mozc.xml. %s will be replaced with
@@ -68,14 +67,69 @@
 
 #ifndef %s
 #define %s
+
+#include <cstddef>
+
 namespace {"""
 
 CPP_FOOTER = """}  // namespace
 #endif  // %s"""
 
 
-def OutputXmlElement(param_dict, element_name, value):
-  print('  <%s>%s</%s>' % (element_name, (value % param_dict), element_name))
+def GetXmlElement(param_dict, element_name, value):
+  return '  <%s>%s</%s>' % (element_name, (value % param_dict), element_name)
+
+
+def GetTextProtoElement(param_dict, element_name, value):
+  return '  %s : "%s"' % (element_name, (value % param_dict))
+
+
+def GetEnginesXml(param_dict, engine_common, engines, setup_arg):
+  """Outputs a XML data for ibus-daemon.
+
+  Args:
+    param_dict: A dictionary to embed options into output string.
+        For example, {'product_name': 'Mozc'}.
+    engine_common: A dictionary from a property name to a property value that
+        are commonly used in all engines. For example, {'language': 'ja'}.
+    engines: A dictionary from a property name to a list of property values of
+        engines. For example, {'name': ['mozc-jp', 'mozc', 'mozc-dv']}.
+    setup_arg: A command line to execute Mozc's configuration tool.
+  Returns:
+    output string in XML.
+  """
+  output = ['<engines>']
+  for i in range(len(engines['name'])):
+    output.append('<engine>')
+    for key in engine_common:
+      output.append(GetXmlElement(param_dict, key, engine_common[key]))
+    if setup_arg:
+      output.append(GetXmlElement(param_dict, 'setup', ' '.join(setup_arg)))
+    for key in engines:
+      output.append(GetXmlElement(param_dict, key, engines[key][i]))
+    output.append('</engine>')
+  output.append('</engines>')
+  return '\n'.join(output)
+
+
+def GetIbusConfigTextProto(param_dict, engines):
+  """Outputs a TextProto data for iBus config.
+
+  Args:
+    param_dict: A dictionary to embed options into output string.
+        For example, {'product_name': 'Mozc'}.
+    engines: A dictionary from a property name to a list of property values of
+        engines. For example, {'name': ['mozc-jp', 'mozc', 'mozc-dv']}.
+  Returns:
+    output string in TextProto.
+  """
+  output = []
+  for i in range(len(engines['name'])):
+    output.append('engines {')
+    for key in engines:
+      output.append(GetTextProtoElement(param_dict, key, engines[key][i]))
+    output.append('}')
+  return '\n'.join(output)
 
 
 def OutputXml(param_dict, component, engine_common, engines, setup_arg):
@@ -90,63 +144,61 @@ def OutputXml(param_dict, component, engine_common, engines, setup_arg):
         are commonly used in all engines. For example, {'language': 'ja'}.
     engines: A dictionary from a property name to a list of property values of
         engines. For example, {'name': ['mozc-jp', 'mozc', 'mozc-dv']}.
+    setup_arg: A command line to execute Mozc's configuration tool.
   """
+  del engine_common, engines, setup_arg
   print('<component>')
   for key in component:
-    OutputXmlElement(param_dict, key, component[key])
-  print('<engines>')
-  for i in range(len(engines['name'])):
-    print('<engine>')
-    for key in engine_common:
-      OutputXmlElement(param_dict, key, engine_common[key])
-    if setup_arg:
-      OutputXmlElement(param_dict, 'setup', ' '.join(setup_arg))
-    for key in engines:
-      OutputXmlElement(param_dict, key, engines[key][i])
-    print('</engine>')
-  print('</engines>')
+    print(GetXmlElement(param_dict, key, component[key]))
+  print('  <engines exec="%s --xml" />' % param_dict['ibus_mozc_path'])
   print('</component>')
 
+  print('''
+<!-- Settings of <engines> and <layout> are stored in ibus_config.textproto -->
+<!-- under the user configuration directory, which is either of: -->
+<!-- * $XDG_CONFIG_HOME/mozc/ibus_config.textproto -->
+<!-- * $HOME/.config/mozc/ibus_config.textproto -->
+<!-- * $HOME/.mozc/ibus_config.textproto -->
+''')
+
 
 def OutputCppVariable(param_dict, prefix, variable_name, value):
   print('const char k%s%s[] = "%s";' % (prefix, variable_name.capitalize(),
                                         (value % param_dict)))
 
 
-def OutputCpp(param_dict, component, engine_common, engines):
+def OutputCpp(param_dict, component, engine_common, engines, setup_arg):
   """Outputs a C++ header file for mozc/unix/ibus/main.cc.
 
   Args:
     param_dict: see OutputXml.
     component: ditto.
     engine_common: ditto.
     engines: ditto.
+    setup_arg: ditto.
   """
   guard_name = 'MOZC_UNIX_IBUS_MAIN_H_'
   print(CPP_HEADER % (guard_name, guard_name))
   for key in component:
     OutputCppVariable(param_dict, 'Component', key, component[key])
   for key in engine_common:
     OutputCppVariable(param_dict, 'Engine', key, engine_common[key])
+  OutputCppVariable(param_dict, 'Engine', 'Setup', ' '.join(setup_arg))
   for key in engines:
     print('const char* kEngine%sArray[] = {' % key.capitalize())
     for i in range(len(engines[key])):
       print('"%s",' % (engines[key][i] % param_dict))
     print('};')
   print('const size_t kEngineArrayLen = %s;' % len(engines['name']))
+  print('const char kEnginesXml[] = R"#(', end='')
+  print(GetEnginesXml(param_dict, engine_common, engines, setup_arg))
+  print(')#";')
+  print('const char kIbusConfigTextProto[] = R"#(', end='')
+  print(GetIbusConfigTextProto(param_dict, engines))
+  print(')#";')
   print(CPP_FOOTER % guard_name)
 
 
-def CheckIBusVersion(options, minimum_version):
-  """Tests if ibus version is equal to or greater than the given value."""
-  command_line = ['pkg-config', '--exists', 'ibus-1.0 >= %s' % minimum_version]
-  return_code = subprocess.call(command_line)
-  if return_code == 0:
-    return True
-  else:
-    return False
-
-
 def main():
   """The main function."""
   parser = optparse.OptionParser(usage='Usage: %prog [options]')
@@ -181,31 +233,23 @@ def main():
       'language': 'ja',
       'icon': '%(ibus_mozc_icon_path)s',
       'rank': '80',
+      # Make sure that the property key 'InputMode' matches to the property name
+      # specified to |ibus_property_new| in unix/ibus/property_handler.cc
+      'icon_prop_key': 'InputMode',
+      'symbol': '&#x3042;',
   }
 
   # DO NOT change the engine name 'mozc-jp'. The names is referenced by
   # unix/ibus/mozc_engine.cc.
   engines_props = {
       'name': ['mozc-jp'],
       'longname': ['%(product_name)s'],
+      'layout': ['default'],
   }
 
-  # IBus 1.5.11 and greater supports 'icon_prop_key'.
-  # See ibus/ibus@23c45b970b195008a54884a1a9d810e7f8b22c5c
-  if CheckIBusVersion(options, '1.5.11'):
-    # Make sure that the property key 'InputMode' matches to the property name
-    # specified to |ibus_property_new| in unix/ibus/property_handler.cc
-    engine_common_props['icon_prop_key'] = 'InputMode'
-
-  if CheckIBusVersion(options, '1.5.0'):
-    engine_common_props['symbol'] = '&#x3042;'
-    engines_props['layout'] = ['default']
-  else:
-    engines_props['layout'] = ['jp']
-
   if options.output_cpp:
     OutputCpp(param_dict, IBUS_COMPONENT_PROPS, engine_common_props,
-              engines_props)
+              engines_props, setup_arg)
   else:
     OutputXml(param_dict, IBUS_COMPONENT_PROPS, engine_common_props,
               engines_props, setup_arg)