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authorWilliam Deegan <bill@baddogconsulting.com>2020-05-06 19:01:37 (GMT)
committerWilliam Deegan <bill@baddogconsulting.com>2020-05-06 19:01:37 (GMT)
commit783dff487bbe940ace7349fa46d6e32b4d0a4705 (patch)
tree3a31d995290257836d26af19b9ec378d3a3ac398 /SCons/SConsign.py
parent37f745c6bc5a818f1a2fd423ac5e483bb2f6370f (diff)
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Reorganize the repo. Moved src/engine/SCons to ./SCons to be more in line with current python packaging practices
Diffstat (limited to 'SCons/SConsign.py')
-rw-r--r--SCons/SConsign.py430
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diff --git a/SCons/SConsign.py b/SCons/SConsign.py
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+"""SCons.SConsign
+
+Writing and reading information to the .sconsign file or files.
+
+"""
+
+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
+
+import SCons.compat
+
+import os
+import pickle
+
+import SCons.dblite
+import SCons.Warnings
+
+from SCons.compat import PICKLE_PROTOCOL
+
+
+def corrupt_dblite_warning(filename):
+ SCons.Warnings.warn(SCons.Warnings.CorruptSConsignWarning,
+ "Ignoring corrupt .sconsign file: %s"%filename)
+
+SCons.dblite.ignore_corrupt_dbfiles = 1
+SCons.dblite.corruption_warning = corrupt_dblite_warning
+
+# XXX Get rid of the global array so this becomes re-entrant.
+sig_files = []
+
+# Info for the database SConsign implementation (now the default):
+# "DataBase" is a dictionary that maps top-level SConstruct directories
+# to open database handles.
+# "DB_Module" is the Python database module to create the handles.
+# "DB_Name" is the base name of the database file (minus any
+# extension the underlying DB module will add).
+DataBase = {}
+DB_Module = SCons.dblite
+DB_Name = ".sconsign"
+DB_sync_list = []
+
+
+def Get_DataBase(dir):
+ global DataBase, DB_Module, DB_Name
+ top = dir.fs.Top
+ if not os.path.isabs(DB_Name) and top.repositories:
+ mode = "c"
+ for d in [top] + top.repositories:
+ if dir.is_under(d):
+ try:
+ return DataBase[d], mode
+ except KeyError:
+ path = d.entry_abspath(DB_Name)
+ try: db = DataBase[d] = DB_Module.open(path, mode)
+ except (IOError, OSError):
+ pass
+ else:
+ if mode != "r":
+ DB_sync_list.append(db)
+ return db, mode
+ mode = "r"
+ try:
+ return DataBase[top], "c"
+ except KeyError:
+ db = DataBase[top] = DB_Module.open(DB_Name, "c")
+ DB_sync_list.append(db)
+ return db, "c"
+ except TypeError:
+ print("DataBase =", DataBase)
+ raise
+
+
+def Reset():
+ """Reset global state. Used by unit tests that end up using
+ SConsign multiple times to get a clean slate for each test."""
+ global sig_files, DB_sync_list
+ sig_files = []
+ DB_sync_list = []
+
+normcase = os.path.normcase
+
+
+def write():
+ global sig_files
+ for sig_file in sig_files:
+ sig_file.write(sync=0)
+ for db in DB_sync_list:
+ try:
+ syncmethod = db.sync
+ except AttributeError:
+ pass # Not all dbm modules have sync() methods.
+ else:
+ syncmethod()
+ try:
+ closemethod = db.close
+ except AttributeError:
+ pass # Not all dbm modules have close() methods.
+ else:
+ closemethod()
+
+
+class SConsignEntry(object):
+ """
+ Wrapper class for the generic entry in a .sconsign file.
+ The Node subclass populates it with attributes as it pleases.
+
+ XXX As coded below, we do expect a '.binfo' attribute to be added,
+ but we'll probably generalize this in the next refactorings.
+ """
+ __slots__ = ("binfo", "ninfo", "__weakref__")
+ current_version_id = 2
+
+ def __init__(self):
+ # Create an object attribute from the class attribute so it ends up
+ # in the pickled data in the .sconsign file.
+ #_version_id = self.current_version_id
+ pass
+
+ def convert_to_sconsign(self):
+ self.binfo.convert_to_sconsign()
+
+ def convert_from_sconsign(self, dir, name):
+ self.binfo.convert_from_sconsign(dir, name)
+
+ def __getstate__(self):
+ state = getattr(self, '__dict__', {}).copy()
+ for obj in type(self).mro():
+ for name in getattr(obj,'__slots__',()):
+ if hasattr(self, name):
+ state[name] = getattr(self, name)
+
+ state['_version_id'] = self.current_version_id
+ try:
+ del state['__weakref__']
+ except KeyError:
+ pass
+ return state
+
+ def __setstate__(self, state):
+ for key, value in state.items():
+ if key not in ('_version_id','__weakref__'):
+ setattr(self, key, value)
+
+
+class Base(object):
+ """
+ This is the controlling class for the signatures for the collection of
+ entries associated with a specific directory. The actual directory
+ association will be maintained by a subclass that is specific to
+ the underlying storage method. This class provides a common set of
+ methods for fetching and storing the individual bits of information
+ that make up signature entry.
+ """
+ def __init__(self):
+ self.entries = {}
+ self.dirty = False
+ self.to_be_merged = {}
+
+ def get_entry(self, filename):
+ """
+ Fetch the specified entry attribute.
+ """
+ return self.entries[filename]
+
+ def set_entry(self, filename, obj):
+ """
+ Set the entry.
+ """
+ self.entries[filename] = obj
+ self.dirty = True
+
+ def do_not_set_entry(self, filename, obj):
+ pass
+
+ def store_info(self, filename, node):
+ entry = node.get_stored_info()
+ entry.binfo.merge(node.get_binfo())
+ self.to_be_merged[filename] = node
+ self.dirty = True
+
+ def do_not_store_info(self, filename, node):
+ pass
+
+ def merge(self):
+ for key, node in self.to_be_merged.items():
+ entry = node.get_stored_info()
+ try:
+ ninfo = entry.ninfo
+ except AttributeError:
+ # This happens with SConf Nodes, because the configuration
+ # subsystem takes direct control over how the build decision
+ # is made and its information stored.
+ pass
+ else:
+ ninfo.merge(node.get_ninfo())
+ self.entries[key] = entry
+ self.to_be_merged = {}
+
+
+class DB(Base):
+ """
+ A Base subclass that reads and writes signature information
+ from a global .sconsign.db* file--the actual file suffix is
+ determined by the database module.
+ """
+ def __init__(self, dir):
+ Base.__init__(self)
+
+ self.dir = dir
+
+ db, mode = Get_DataBase(dir)
+
+ # Read using the path relative to the top of the Repository
+ # (self.dir.tpath) from which we're fetching the signature
+ # information.
+ path = normcase(dir.get_tpath())
+ try:
+ rawentries = db[path]
+ except KeyError:
+ pass
+ else:
+ try:
+ self.entries = pickle.loads(rawentries)
+ if not isinstance(self.entries, dict):
+ self.entries = {}
+ raise TypeError
+ except KeyboardInterrupt:
+ raise
+ except Exception as e:
+ SCons.Warnings.warn(SCons.Warnings.CorruptSConsignWarning,
+ "Ignoring corrupt sconsign entry : %s (%s)\n"%(self.dir.get_tpath(), e))
+ for key, entry in self.entries.items():
+ entry.convert_from_sconsign(dir, key)
+
+ if mode == "r":
+ # This directory is actually under a repository, which means
+ # likely they're reaching in directly for a dependency on
+ # a file there. Don't actually set any entry info, so we
+ # won't try to write to that .sconsign.dblite file.
+ self.set_entry = self.do_not_set_entry
+ self.store_info = self.do_not_store_info
+
+ global sig_files
+ sig_files.append(self)
+
+ def write(self, sync=1):
+ if not self.dirty:
+ return
+
+ self.merge()
+
+ db, mode = Get_DataBase(self.dir)
+
+ # Write using the path relative to the top of the SConstruct
+ # directory (self.dir.path), not relative to the top of
+ # the Repository; we only write to our own .sconsign file,
+ # not to .sconsign files in Repositories.
+ path = normcase(self.dir.get_internal_path())
+ for key, entry in self.entries.items():
+ entry.convert_to_sconsign()
+ db[path] = pickle.dumps(self.entries, PICKLE_PROTOCOL)
+
+ if sync:
+ try:
+ syncmethod = db.sync
+ except AttributeError:
+ # Not all anydbm modules have sync() methods.
+ pass
+ else:
+ syncmethod()
+
+
+class Dir(Base):
+ def __init__(self, fp=None, dir=None):
+ """
+ fp - file pointer to read entries from
+ """
+ Base.__init__(self)
+
+ if not fp:
+ return
+
+ self.entries = pickle.load(fp)
+ if not isinstance(self.entries, dict):
+ self.entries = {}
+ raise TypeError
+
+ if dir:
+ for key, entry in self.entries.items():
+ entry.convert_from_sconsign(dir, key)
+
+
+class DirFile(Dir):
+ """
+ Encapsulates reading and writing a per-directory .sconsign file.
+ """
+ def __init__(self, dir):
+ """
+ dir - the directory for the file
+ """
+
+ self.dir = dir
+ self.sconsign = os.path.join(dir.get_internal_path(), '.sconsign')
+
+ try:
+ fp = open(self.sconsign, 'rb')
+ except IOError:
+ fp = None
+
+ try:
+ Dir.__init__(self, fp, dir)
+ except KeyboardInterrupt:
+ raise
+ except Exception:
+ SCons.Warnings.warn(SCons.Warnings.CorruptSConsignWarning,
+ "Ignoring corrupt .sconsign file: %s"%self.sconsign)
+
+ try:
+ fp.close()
+ except AttributeError:
+ pass
+
+ global sig_files
+ sig_files.append(self)
+
+ def write(self, sync=1):
+ """
+ Write the .sconsign file to disk.
+
+ Try to write to a temporary file first, and rename it if we
+ succeed. If we can't write to the temporary file, it's
+ probably because the directory isn't writable (and if so,
+ how did we build anything in this directory, anyway?), so
+ try to write directly to the .sconsign file as a backup.
+ If we can't rename, try to copy the temporary contents back
+ to the .sconsign file. Either way, always try to remove
+ the temporary file at the end.
+ """
+ if not self.dirty:
+ return
+
+ self.merge()
+
+ temp = os.path.join(self.dir.get_internal_path(), '.scons%d' % os.getpid())
+ try:
+ file = open(temp, 'wb')
+ fname = temp
+ except IOError:
+ try:
+ file = open(self.sconsign, 'wb')
+ fname = self.sconsign
+ except IOError:
+ return
+ for key, entry in self.entries.items():
+ entry.convert_to_sconsign()
+ pickle.dump(self.entries, file, PICKLE_PROTOCOL)
+ file.close()
+ if fname != self.sconsign:
+ try:
+ mode = os.stat(self.sconsign)[0]
+ os.chmod(self.sconsign, 0o666)
+ os.unlink(self.sconsign)
+ except (IOError, OSError):
+ # Try to carry on in the face of either OSError
+ # (things like permission issues) or IOError (disk
+ # or network issues). If there's a really dangerous
+ # issue, it should get re-raised by the calls below.
+ pass
+ try:
+ os.rename(fname, self.sconsign)
+ except OSError:
+ # An OSError failure to rename may indicate something
+ # like the directory has no write permission, but
+ # the .sconsign file itself might still be writable,
+ # so try writing on top of it directly. An IOError
+ # here, or in any of the following calls, would get
+ # raised, indicating something like a potentially
+ # serious disk or network issue.
+ with open(self.sconsign, 'wb') as f, open(fname, 'rb') as f2:
+ f.write(f2.read())
+ os.chmod(self.sconsign, mode)
+ try:
+ os.unlink(temp)
+ except (IOError, OSError):
+ pass
+
+ForDirectory = DB
+
+
+def File(name, dbm_module=None):
+ """
+ Arrange for all signatures to be stored in a global .sconsign.db*
+ file.
+ """
+ global ForDirectory, DB_Name, DB_Module
+ if name is None:
+ ForDirectory = DirFile
+ DB_Module = None
+ else:
+ ForDirectory = DB
+ DB_Name = name
+ if dbm_module is not None:
+ DB_Module = dbm_module
+
+# Local Variables:
+# tab-width:4
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=4 shiftwidth=4: