1 files changed, 156 insertions, 0 deletions

diff --git a/scripts/lib/wic/plugin.py b/scripts/lib/wic/plugin.py
new file mode 100644
index 0000000000..61c5859bac
--- /dev/null
+++ b/scripts/lib/wic/plugin.py
@@ -0,0 +1,156 @@
+#!/usr/bin/python -tt
+#
+# Copyright (c) 2011 Intel, Inc.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the Free
+# Software Foundation; version 2 of the License
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc., 59
+# Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+import os, sys
+
+from wic import msger
+from wic import pluginbase
+from wic.utils import errors
+from wic.utils.oe.misc import *
+
+__ALL__ = ['PluginMgr', 'pluginmgr']
+
+PLUGIN_TYPES = ["imager", "source"]
+
+PLUGIN_DIR = "/lib/wic/plugins" # relative to scripts
+SCRIPTS_PLUGIN_DIR = "scripts" + PLUGIN_DIR
+
+class PluginMgr(object):
+    plugin_dirs = {}
+
+    # make the manager class as singleton
+    _instance = None
+    def __new__(cls, *args, **kwargs):
+        if not cls._instance:
+            cls._instance = super(PluginMgr, cls).__new__(cls, *args, **kwargs)
+
+        return cls._instance
+
+    def __init__(self):
+        wic_path = os.path.dirname(__file__)
+        eos = wic_path.find('scripts') + len('scripts')
+        scripts_path = wic_path[:eos]
+        self.scripts_path = scripts_path
+        self.plugin_dir = scripts_path + PLUGIN_DIR
+        self.layers_path = None
+
+    def _build_plugin_dir_list(self, dl, ptype):
+        if self.layers_path is None:
+            self.layers_path = get_bitbake_var("BBLAYERS")
+        layer_dirs = []
+
+        if self.layers_path is not None:
+            for layer_path in self.layers_path.split():
+                path = os.path.join(layer_path, SCRIPTS_PLUGIN_DIR, ptype)
+                layer_dirs.append(path)
+
+        path = os.path.join(dl, ptype)
+        layer_dirs.append(path)
+
+        return layer_dirs
+
+    def append_dirs(self, dirs):
+        for path in dirs:
+            self._add_plugindir(path)
+
+        # load all the plugins AGAIN
+        self._load_all()
+
+    def _add_plugindir(self, path):
+        path = os.path.abspath(os.path.expanduser(path))
+
+        if not os.path.isdir(path):
+            msger.debug("Plugin dir is not a directory or does not exist: %s"\
+                          % path)
+            return
+
+        if path not in self.plugin_dirs:
+            self.plugin_dirs[path] = False
+            # the value True/False means "loaded"
+
+    def _load_all(self):
+        for (pdir, loaded) in self.plugin_dirs.iteritems():
+            if loaded: continue
+
+            sys.path.insert(0, pdir)
+            for mod in [x[:-3] for x in os.listdir(pdir) if x.endswith(".py")]:
+                if mod and mod != '__init__':
+                    if mod in sys.modules:
+                        #self.plugin_dirs[pdir] = True
+                        msger.warning("Module %s already exists, skip" % mod)
+                    else:
+                        try:
+                            pymod = __import__(mod)
+                            self.plugin_dirs[pdir] = True
+                            msger.debug("Plugin module %s:%s imported"\
+                                        % (mod, pymod.__file__))
+                        except ImportError, err:
+                            msg = 'Failed to load plugin %s/%s: %s' \
+                                % (os.path.basename(pdir), mod, err)
+                            msger.warning(msg)
+
+            del(sys.path[0])
+
+    def get_plugins(self, ptype):
+        """ the return value is dict of name:class pairs """
+
+        if ptype not in PLUGIN_TYPES:
+            raise errors.CreatorError('%s is not valid plugin type' % ptype)
+
+        plugins_dir = self._build_plugin_dir_list(self.plugin_dir, ptype)
+
+        self.append_dirs(plugins_dir)
+
+        return pluginbase.get_plugins(ptype)
+
+    def get_source_plugins(self):
+        """
+        Return list of available source plugins.
+        """
+        plugins_dir = self._build_plugin_dir_list(self.plugin_dir, 'source')
+
+        self.append_dirs(plugins_dir)
+
+        plugins = []
+
+        for _source_name, klass in self.get_plugins('source').iteritems():
+            plugins.append(_source_name)
+
+        return plugins
+
+
+    def get_source_plugin_methods(self, source_name, methods):
+        """
+        The methods param is a dict with the method names to find.  On
+        return, the dict values will be filled in with pointers to the
+        corresponding methods.  If one or more methods are not found,
+        None is returned.
+        """
+        return_methods = None
+        for _source_name, klass in self.get_plugins('source').iteritems():
+            if _source_name == source_name:
+                for _method_name in methods.keys():
+                    if not hasattr(klass, _method_name):
+                        msger.warning("Unimplemented %s source interface for: %s"\
+                                      % (_method_name, _source_name))
+                        return None
+                    func = getattr(klass, _method_name)
+                    methods[_method_name] = func
+                    return_methods = methods
+        return return_methods
+
+pluginmgr = PluginMgr()