symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/ihooks.py
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/ihooks.py	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,522 @@
+"""Import hook support.
+
+Consistent use of this module will make it possible to change the
+different mechanisms involved in loading modules independently.
+
+While the built-in module imp exports interfaces to the built-in
+module searching and loading algorithm, and it is possible to replace
+the built-in function __import__ in order to change the semantics of
+the import statement, until now it has been difficult to combine the
+effect of different __import__ hacks, like loading modules from URLs
+by rimport.py, or restricted execution by rexec.py.
+
+This module defines three new concepts:
+
+1) A "file system hooks" class provides an interface to a filesystem.
+
+One hooks class is defined (Hooks), which uses the interface provided
+by standard modules os and os.path.  It should be used as the base
+class for other hooks classes.
+
+2) A "module loader" class provides an interface to search for a
+module in a search path and to load it.  It defines a method which
+searches for a module in a single directory; by overriding this method
+one can redefine the details of the search.  If the directory is None,
+built-in and frozen modules are searched instead.
+
+Two module loader class are defined, both implementing the search
+strategy used by the built-in __import__ function: ModuleLoader uses
+the imp module's find_module interface, while HookableModuleLoader
+uses a file system hooks class to interact with the file system.  Both
+use the imp module's load_* interfaces to actually load the module.
+
+3) A "module importer" class provides an interface to import a
+module, as well as interfaces to reload and unload a module.  It also
+provides interfaces to install and uninstall itself instead of the
+default __import__ and reload (and unload) functions.
+
+One module importer class is defined (ModuleImporter), which uses a
+module loader instance passed in (by default HookableModuleLoader is
+instantiated).
+
+The classes defined here should be used as base classes for extended
+functionality along those lines.
+
+If a module importer class supports dotted names, its import_module()
+must return a different value depending on whether it is called on
+behalf of a "from ... import ..." statement or not.  (This is caused
+by the way the __import__ hook is used by the Python interpreter.)  It
+would also do wise to install a different version of reload().
+
+"""
+from warnings import warnpy3k
+warnpy3k("the ihooks module has been removed in Python 3.0", stacklevel=2)
+del warnpy3k
+
+import __builtin__
+import imp
+import os
+import sys
+
+__all__ = ["BasicModuleLoader","Hooks","ModuleLoader","FancyModuleLoader",
+           "BasicModuleImporter","ModuleImporter","install","uninstall"]
+
+VERBOSE = 0
+
+
+from imp import C_EXTENSION, PY_SOURCE, PY_COMPILED
+from imp import C_BUILTIN, PY_FROZEN, PKG_DIRECTORY
+BUILTIN_MODULE = C_BUILTIN
+FROZEN_MODULE = PY_FROZEN
+
+
+class _Verbose:
+
+    def __init__(self, verbose = VERBOSE):
+        self.verbose = verbose
+
+    def get_verbose(self):
+        return self.verbose
+
+    def set_verbose(self, verbose):
+        self.verbose = verbose
+
+    # XXX The following is an experimental interface
+
+    def note(self, *args):
+        if self.verbose:
+            self.message(*args)
+
+    def message(self, format, *args):
+        if args:
+            print format%args
+        else:
+            print format
+
+
+class BasicModuleLoader(_Verbose):
+
+    """Basic module loader.
+
+    This provides the same functionality as built-in import.  It
+    doesn't deal with checking sys.modules -- all it provides is
+    find_module() and a load_module(), as well as find_module_in_dir()
+    which searches just one directory, and can be overridden by a
+    derived class to change the module search algorithm when the basic
+    dependency on sys.path is unchanged.
+
+    The interface is a little more convenient than imp's:
+    find_module(name, [path]) returns None or 'stuff', and
+    load_module(name, stuff) loads the module.
+
+    """
+
+    def find_module(self, name, path = None):
+        if path is None:
+            path = [None] + self.default_path()
+        for dir in path:
+            stuff = self.find_module_in_dir(name, dir)
+            if stuff: return stuff
+        return None
+
+    def default_path(self):
+        return sys.path
+
+    def find_module_in_dir(self, name, dir):
+        if dir is None:
+            return self.find_builtin_module(name)
+        else:
+            try:
+                return imp.find_module(name, [dir])
+            except ImportError:
+                return None
+
+    def find_builtin_module(self, name):
+        # XXX frozen packages?
+        if imp.is_builtin(name):
+            return None, '', ('', '', BUILTIN_MODULE)
+        if imp.is_frozen(name):
+            return None, '', ('', '', FROZEN_MODULE)
+        return None
+
+    def load_module(self, name, stuff):
+        file, filename, info = stuff
+        try:
+            return imp.load_module(name, file, filename, info)
+        finally:
+            if file: file.close()
+
+
+class Hooks(_Verbose):
+
+    """Hooks into the filesystem and interpreter.
+
+    By deriving a subclass you can redefine your filesystem interface,
+    e.g. to merge it with the URL space.
+
+    This base class behaves just like the native filesystem.
+
+    """
+
+    # imp interface
+    def get_suffixes(self): return imp.get_suffixes()
+    def new_module(self, name): return imp.new_module(name)
+    def is_builtin(self, name): return imp.is_builtin(name)
+    def init_builtin(self, name): return imp.init_builtin(name)
+    def is_frozen(self, name): return imp.is_frozen(name)
+    def init_frozen(self, name): return imp.init_frozen(name)
+    def get_frozen_object(self, name): return imp.get_frozen_object(name)
+    def load_source(self, name, filename, file=None):
+        return imp.load_source(name, filename, file)
+    def load_compiled(self, name, filename, file=None):
+        return imp.load_compiled(name, filename, file)
+    def load_dynamic(self, name, filename, file=None):
+        return imp.load_dynamic(name, filename, file)
+    def load_package(self, name, filename, file=None):
+        return imp.load_module(name, file, filename, ("", "", PKG_DIRECTORY))
+
+    def add_module(self, name):
+        d = self.modules_dict()
+        if name in d: return d[name]
+        d[name] = m = self.new_module(name)
+        return m
+
+    # sys interface
+    def modules_dict(self): return sys.modules
+    def default_path(self): return sys.path
+
+    def path_split(self, x): return os.path.split(x)
+    def path_join(self, x, y): return os.path.join(x, y)
+    def path_isabs(self, x): return os.path.isabs(x)
+    # etc.
+
+    def path_exists(self, x): return os.path.exists(x)
+    def path_isdir(self, x): return os.path.isdir(x)
+    def path_isfile(self, x): return os.path.isfile(x)
+    def path_islink(self, x): return os.path.islink(x)
+    # etc.
+
+    def openfile(self, *x): return open(*x)
+    openfile_error = IOError
+    def listdir(self, x): return os.listdir(x)
+    listdir_error = os.error
+    # etc.
+
+
+class ModuleLoader(BasicModuleLoader):
+
+    """Default module loader; uses file system hooks.
+
+    By defining suitable hooks, you might be able to load modules from
+    other sources than the file system, e.g. from compressed or
+    encrypted files, tar files or (if you're brave!) URLs.
+
+    """
+
+    def __init__(self, hooks = None, verbose = VERBOSE):
+        BasicModuleLoader.__init__(self, verbose)
+        self.hooks = hooks or Hooks(verbose)
+
+    def default_path(self):
+        return self.hooks.default_path()
+
+    def modules_dict(self):
+        return self.hooks.modules_dict()
+
+    def get_hooks(self):
+        return self.hooks
+
+    def set_hooks(self, hooks):
+        self.hooks = hooks
+
+    def find_builtin_module(self, name):
+        # XXX frozen packages?
+        if self.hooks.is_builtin(name):
+            return None, '', ('', '', BUILTIN_MODULE)
+        if self.hooks.is_frozen(name):
+            return None, '', ('', '', FROZEN_MODULE)
+        return None
+
+    def find_module_in_dir(self, name, dir, allow_packages=1):
+        if dir is None:
+            return self.find_builtin_module(name)
+        if allow_packages:
+            fullname = self.hooks.path_join(dir, name)
+            if self.hooks.path_isdir(fullname):
+                stuff = self.find_module_in_dir("__init__", fullname, 0)
+                if stuff:
+                    file = stuff[0]
+                    if file: file.close()
+                    return None, fullname, ('', '', PKG_DIRECTORY)
+        for info in self.hooks.get_suffixes():
+            suff, mode, type = info
+            fullname = self.hooks.path_join(dir, name+suff)
+            try:
+                fp = self.hooks.openfile(fullname, mode)
+                return fp, fullname, info
+            except self.hooks.openfile_error:
+                pass
+        return None
+
+    def load_module(self, name, stuff):
+        file, filename, info = stuff
+        (suff, mode, type) = info
+        try:
+            if type == BUILTIN_MODULE:
+                return self.hooks.init_builtin(name)
+            if type == FROZEN_MODULE:
+                return self.hooks.init_frozen(name)
+            if type == C_EXTENSION:
+                m = self.hooks.load_dynamic(name, filename, file)
+            elif type == PY_SOURCE:
+                m = self.hooks.load_source(name, filename, file)
+            elif type == PY_COMPILED:
+                m = self.hooks.load_compiled(name, filename, file)
+            elif type == PKG_DIRECTORY:
+                m = self.hooks.load_package(name, filename, file)
+            else:
+                raise ImportError, "Unrecognized module type (%r) for %s" % \
+                      (type, name)
+        finally:
+            if file: file.close()
+        m.__file__ = filename
+        return m
+
+
+class FancyModuleLoader(ModuleLoader):
+
+    """Fancy module loader -- parses and execs the code itself."""
+
+    def load_module(self, name, stuff):
+        file, filename, (suff, mode, type) = stuff
+        realfilename = filename
+        path = None
+
+        if type == PKG_DIRECTORY:
+            initstuff = self.find_module_in_dir("__init__", filename, 0)
+            if not initstuff:
+                raise ImportError, "No __init__ module in package %s" % name
+            initfile, initfilename, initinfo = initstuff
+            initsuff, initmode, inittype = initinfo
+            if inittype not in (PY_COMPILED, PY_SOURCE):
+                if initfile: initfile.close()
+                raise ImportError, \
+                    "Bad type (%r) for __init__ module in package %s" % (
+                    inittype, name)
+            path = [filename]
+            file = initfile
+            realfilename = initfilename
+            type = inittype
+
+        if type == FROZEN_MODULE:
+            code = self.hooks.get_frozen_object(name)
+        elif type == PY_COMPILED:
+            import marshal
+            file.seek(8)
+            code = marshal.load(file)
+        elif type == PY_SOURCE:
+            data = file.read()
+            code = compile(data, realfilename, 'exec')
+        else:
+            return ModuleLoader.load_module(self, name, stuff)
+
+        m = self.hooks.add_module(name)
+        if path:
+            m.__path__ = path
+        m.__file__ = filename
+        try:
+            exec code in m.__dict__
+        except:
+            d = self.hooks.modules_dict()
+            if name in d:
+                del d[name]
+            raise
+        return m
+
+
+class BasicModuleImporter(_Verbose):
+
+    """Basic module importer; uses module loader.
+
+    This provides basic import facilities but no package imports.
+
+    """
+
+    def __init__(self, loader = None, verbose = VERBOSE):
+        _Verbose.__init__(self, verbose)
+        self.loader = loader or ModuleLoader(None, verbose)
+        self.modules = self.loader.modules_dict()
+
+    def get_loader(self):
+        return self.loader
+
+    def set_loader(self, loader):
+        self.loader = loader
+
+    def get_hooks(self):
+        return self.loader.get_hooks()
+
+    def set_hooks(self, hooks):
+        return self.loader.set_hooks(hooks)
+
+    def import_module(self, name, globals={}, locals={}, fromlist=[]):
+        name = str(name)
+        if name in self.modules:
+            return self.modules[name] # Fast path
+        stuff = self.loader.find_module(name)
+        if not stuff:
+            raise ImportError, "No module named %s" % name
+        return self.loader.load_module(name, stuff)
+
+    def reload(self, module, path = None):
+        name = str(module.__name__)
+        stuff = self.loader.find_module(name, path)
+        if not stuff:
+            raise ImportError, "Module %s not found for reload" % name
+        return self.loader.load_module(name, stuff)
+
+    def unload(self, module):
+        del self.modules[str(module.__name__)]
+        # XXX Should this try to clear the module's namespace?
+
+    def install(self):
+        self.save_import_module = __builtin__.__import__
+        self.save_reload = __builtin__.reload
+        if not hasattr(__builtin__, 'unload'):
+            __builtin__.unload = None
+        self.save_unload = __builtin__.unload
+        __builtin__.__import__ = self.import_module
+        __builtin__.reload = self.reload
+        __builtin__.unload = self.unload
+
+    def uninstall(self):
+        __builtin__.__import__ = self.save_import_module
+        __builtin__.reload = self.save_reload
+        __builtin__.unload = self.save_unload
+        if not __builtin__.unload:
+            del __builtin__.unload
+
+
+class ModuleImporter(BasicModuleImporter):
+
+    """A module importer that supports packages."""
+
+    def import_module(self, name, globals=None, locals=None, fromlist=None):
+        parent = self.determine_parent(globals)
+        q, tail = self.find_head_package(parent, str(name))
+        m = self.load_tail(q, tail)
+        if not fromlist:
+            return q
+        if hasattr(m, "__path__"):
+            self.ensure_fromlist(m, fromlist)
+        return m
+
+    def determine_parent(self, globals):
+        if not globals or not "__name__" in globals:
+            return None
+        pname = globals['__name__']
+        if "__path__" in globals:
+            parent = self.modules[pname]
+            assert globals is parent.__dict__
+            return parent
+        if '.' in pname:
+            i = pname.rfind('.')
+            pname = pname[:i]
+            parent = self.modules[pname]
+            assert parent.__name__ == pname
+            return parent
+        return None
+
+    def find_head_package(self, parent, name):
+        if '.' in name:
+            i = name.find('.')
+            head = name[:i]
+            tail = name[i+1:]
+        else:
+            head = name
+            tail = ""
+        if parent:
+            qname = "%s.%s" % (parent.__name__, head)
+        else:
+            qname = head
+        q = self.import_it(head, qname, parent)
+        if q: return q, tail
+        if parent:
+            qname = head
+            parent = None
+            q = self.import_it(head, qname, parent)
+            if q: return q, tail
+        raise ImportError, "No module named " + qname
+
+    def load_tail(self, q, tail):
+        m = q
+        while tail:
+            i = tail.find('.')
+            if i < 0: i = len(tail)
+            head, tail = tail[:i], tail[i+1:]
+            mname = "%s.%s" % (m.__name__, head)
+            m = self.import_it(head, mname, m)
+            if not m:
+                raise ImportError, "No module named " + mname
+        return m
+
+    def ensure_fromlist(self, m, fromlist, recursive=0):
+        for sub in fromlist:
+            if sub == "*":
+                if not recursive:
+                    try:
+                        all = m.__all__
+                    except AttributeError:
+                        pass
+                    else:
+                        self.ensure_fromlist(m, all, 1)
+                continue
+            if sub != "*" and not hasattr(m, sub):
+                subname = "%s.%s" % (m.__name__, sub)
+                submod = self.import_it(sub, subname, m)
+                if not submod:
+                    raise ImportError, "No module named " + subname
+
+    def import_it(self, partname, fqname, parent, force_load=0):
+        if not partname:
+            raise ValueError, "Empty module name"
+        if not force_load:
+            try:
+                return self.modules[fqname]
+            except KeyError:
+                pass
+        try:
+            path = parent and parent.__path__
+        except AttributeError:
+            return None
+        partname = str(partname)
+        stuff = self.loader.find_module(partname, path)
+        if not stuff:
+            return None
+        fqname = str(fqname)
+        m = self.loader.load_module(fqname, stuff)
+        if parent:
+            setattr(parent, partname, m)
+        return m
+
+    def reload(self, module):
+        name = str(module.__name__)
+        if '.' not in name:
+            return self.import_it(name, name, None, force_load=1)
+        i = name.rfind('.')
+        pname = name[:i]
+        parent = self.modules[pname]
+        return self.import_it(name[i+1:], name, parent, force_load=1)
+
+
+default_importer = None
+current_importer = None
+
+def install(importer = None):
+    global current_importer
+    current_importer = importer or default_importer or ModuleImporter()
+    current_importer.install()
+
+def uninstall():
+    global current_importer
+    current_importer.uninstall()