tools: moveconfig: make Slot.poll() more readable with helper methods

The Slot.poll() method is already complicated and a new feature
we are going to add will make it more difficult to understand
the execution flow.

Refactor it with helper methods, .handle_error(), .do_defconfig(),
.do_autoconf(), .do_savedefconfig, and .update_defconfig().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

tools/moveconfig.py

@@ -633,13 +633,10 @@ class Slot:
         """
         if self.state != STATE_IDLE:
             return False
-        cmd = list(self.make_cmd)
-        cmd.append(defconfig)
-        self.ps = subprocess.Popen(cmd, stdout=self.devnull,
-                                   stderr=subprocess.PIPE)
+
         self.defconfig = defconfig
-        self.state = STATE_DEFCONFIG
         self.log = ''
+        self.do_defconfig()
         return True
 
     def poll(self):
@@ -665,21 +662,65 @@ class Slot:
             return False
 
         if self.ps.poll() != 0:
+            self.handle_error()
+        elif self.state == STATE_DEFCONFIG:
+            self.do_autoconf()
+        elif self.state == STATE_AUTOCONF:
+            self.do_savedefconfig()
+        elif self.state == STATE_SAVEDEFCONFIG:
+            self.update_defconfig()
+        else:
+            sys.exit("Internal Error. This should not happen.")
+
+        return True if self.state == STATE_IDLE else False
+
+    def handle_error(self):
+        """Handle error cases."""
+
         self.log += color_text(self.options.color, COLOR_LIGHT_RED,
                                "Failed to process.\n")
         if self.options.verbose:
             self.log += color_text(self.options.color, COLOR_LIGHT_CYAN,
                                    self.ps.stderr.read())
         self.finish(False)
-            return True
 
-        if self.state == STATE_AUTOCONF:
+    def do_defconfig(self):
+        """Run 'make <board>_defconfig' to create the .config file."""
+
+        cmd = list(self.make_cmd)
+        cmd.append(self.defconfig)
+        self.ps = subprocess.Popen(cmd, stdout=self.devnull,
+                                   stderr=subprocess.PIPE)
+        self.state = STATE_DEFCONFIG
+
+    def do_autoconf(self):
+        """Run 'make include/config/auto.conf'."""
+
+        self.cross_compile = self.parser.get_cross_compile()
+        if self.cross_compile is None:
+            self.log += color_text(self.options.color, COLOR_YELLOW,
+                                   "Compiler is missing.  Do nothing.\n")
+            self.finish(False)
+            return
+
+        cmd = list(self.make_cmd)
+        if self.cross_compile:
+            cmd.append('CROSS_COMPILE=%s' % self.cross_compile)
+        cmd.append('KCONFIG_IGNORE_DUPLICATES=1')
+        cmd.append('include/config/auto.conf')
+        self.ps = subprocess.Popen(cmd, stdout=self.devnull,
+                                   stderr=subprocess.PIPE)
+        self.state = STATE_AUTOCONF
+
+    def do_savedefconfig(self):
+        """Update the .config and run 'make savedefconfig'."""
+
         (updated, log) = self.parser.update_dotconfig()
         self.log += log
 
         if not self.options.force_sync and not updated:
             self.finish(True)
-                return True
+            return
         if updated:
             self.log += color_text(self.options.color, COLOR_LIGHT_GREEN,
                                    "Syncing by savedefconfig...\n")
@@ -691,9 +732,10 @@ class Slot:
         self.ps = subprocess.Popen(cmd, stdout=self.devnull,
                                    stderr=subprocess.PIPE)
         self.state = STATE_SAVEDEFCONFIG
-            return False
 
-        if self.state == STATE_SAVEDEFCONFIG:
+    def update_defconfig(self):
+        """Update the input defconfig and go back to the idle state."""
+
         self.log += self.parser.check_defconfig()
         orig_defconfig = os.path.join('configs', self.defconfig)
         new_defconfig = os.path.join(self.build_dir, 'defconfig')
@@ -706,24 +748,6 @@ class Slot:
         if not self.options.dry_run and updated:
             shutil.move(new_defconfig, orig_defconfig)
         self.finish(True)
-            return True
-
-        self.cross_compile = self.parser.get_cross_compile()
-        if self.cross_compile is None:
-            self.log += color_text(self.options.color, COLOR_YELLOW,
-                                   "Compiler is missing.  Do nothing.\n")
-            self.finish(False)
-            return True
-
-        cmd = list(self.make_cmd)
-        if self.cross_compile:
-            cmd.append('CROSS_COMPILE=%s' % self.cross_compile)
-        cmd.append('KCONFIG_IGNORE_DUPLICATES=1')
-        cmd.append('include/config/auto.conf')
-        self.ps = subprocess.Popen(cmd, stdout=self.devnull,
-                                   stderr=subprocess.PIPE)
-        self.state = STATE_AUTOCONF
-        return False
 
     def finish(self, success):
         """Display log along with progress and go to the idle state.