~azzar1/unity/add-show-desktop-key : contents of ivle/testfilespace.py at revision 1188

~azzar1/unity/add-show-desktop-key : (revision 1188)

# IVLE - Informatics Virtual Learning Environment
# Copyright (C) 2007-2008 The University of Melbourne
#
# 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; either version 2 of the License, or
# (at your option) any later version.
#
# 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

# Module: TestFilespace
# Author: Dilshan Angampitiya
#         Steven Bird (revisions)
#         David Coles (revisions and moved to module)
# Date:   24/1/2008

import StringIO

class TestFilespace:
    """
    Our dummy file system which is accessed by code being tested.
    Implemented as a dictionary which maps filenames to strings
    """
    def __init__(self, files=None):
        "Initialise, optionally with filename-filedata pairs"

        if files == None:
            files = {}

        # dict mapping files to strings
        self._files = {}
        self._files.update(files)
        # set of file names
        self._modified_files = set([])
        # dict mapping files to stringIO objects
        self._open_files = {}

    def add_file(self, filename, data):
        " Add a file to the filespace "
        self._files[filename] = data

    def openfile(self, filename, mode='r'):
        """ Open a file from the filespace with the given mode.
        Return a StringIO subclass object with the file contents.
        """
        # currently very messy, needs to be cleaned up
        # Probably most of this should be in the initialiser to the TestStringIO
        
        import re

        if filename in self._open_files:
            raise IOError("File already open: %s" %filename)

        if not re.compile("[rwa][+b]{0,2}").match(mode):
            raise IOError("invalid mode %s" %mode)
        
        ## TODO: validate filename?
        
        mode.replace("b",'')
        
        # initialise the file properly (truncate/create if required)
        if mode[0] == 'w':
            self._files[filename] = ''
            self._modified_files.add(filename)
        elif filename not in self._files:
            if mode[0] == 'a':
                self._files[filename] = ''
                self._modified_files.add(filename)
            else:
                raise IOError(2, "Access to file denied: %s" %filename)

        # for append mode, remember the existing data
        if mode[0] == 'a':
            existing_data = self._files[filename]
        else:
            existing_data = ""

        # determine what operations are allowed
        reading_ok = (len(mode) == 2 or mode[0] == 'r')
        writing_ok = (len(mode) == 2 or mode[0] in 'wa')

        # for all writing modes, start off with blank file
        if mode[0] == 'w':
            initial_data = ''
        else:
            initial_data = self._files[filename]

        file_object = TestStringIO(initial_data, filename, self, reading_ok, writing_ok, existing_data)
        self._open_files[filename] = file_object
        
        return file_object

    def flush_all(self):
        """ Flush all open files
        """
        for file_object in self._open_files.values():
            file_object.flush()

    def updatefile(self,filename, data):
        """ Callback function used by an open file to inform when it has been updated.
        """
        if filename in self._open_files:
            self._files[filename] = data
            if self._open_files[filename].is_modified():
                self._modified_files.add(filename)
        else:
            raise IOError(2, "Access to file denied: %s" %filename)

    def closefile(self, filename):
        """ Callback function used by an open file to inform when it has been closed.
        """
        if filename in self._open_files:
            del self._open_files[filename]

    def get_modified_files(self):
        """" A subset of the filespace containing only those files which have been
        modified
        """
        modified_files = {}
        for filename in self._modified_files:
            modified_files[filename] = self._files[filename]

        return modified_files

    def get_open_files(self):
        " Return the names of all open files "
        return self._open_files.keys()
            
    def copy(self):
        """ Return a copy of the current filespace.
        Only the files are copied, not the modified or open file lists.
        """
        self.flush_all()
        return TestFilespace(self._files)

class TestStringIO(StringIO.StringIO):
    """
    A subclass of StringIO which acts as a file in our dummy file system
    """
    def __init__(self, string, filename, filespace, reading_ok, writing_ok, existing_data):
        """ Initialise with the filedata, file name and infomation on what ops are
        acceptable """
        StringIO.StringIO.__init__(self, string)
        self._filename = filename
        self._filespace = filespace
        self._reading_ok = reading_ok
        self._writing_ok = writing_ok
        self._existing_data = existing_data
        self._modified = False
        self._open = True

    # Override all standard file ops. Make sure that they are valid with the given
    # permissions and if so then call the corresponding method in StringIO
    
    def read(self, *args):
        if not self._reading_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.read(self, *args)

    def readline(self, *args):
        if not self._reading_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.readline(self, *args)

    def readlines(self, *args):
        if not self._reading_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.readlines(self, *args)

    def seek(self, *args):
        if not self._reading_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.seek(self, *args)

    def truncate(self, *args):
        self._modified = True
        if not self._writing_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.truncate(self, *args)
        
    def write(self, *args):
        self._modified = True
        if not self._writing_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.write(self, *args)

    def writelines(self, *args):
        self._modified = True
        if not self._writing_ok:
            raise IOError(9, "Bad file descriptor")
        else:
            return StringIO.StringIO.writelines(self, *args)

    def is_modified(self):
        " Return true if the file has been written to, or truncated"
        return self._modified
        
    def flush(self):
        " Update the contents of the filespace with the new data "
        self._filespace.updatefile(self._filename, self._existing_data+self.getvalue())
        return StringIO.StringIO.flush(self)

    def close(self):
        " Flush the file and close it "
        self.flush()
        self._filespace.closefile(self._filename)
        return StringIO.StringIO.close(self)


1079 by William Grant Merge setup-refactor branch. This completely breaks existing installations;	1	# IVLE - Informatics Virtual Learning Environment
	2	# Copyright (C) 2007-2008 The University of Melbourne
	3	#
	4	# This program is free software; you can redistribute it and/or modify
	5	# it under the terms of the GNU General Public License as published by
	6	# the Free Software Foundation; either version 2 of the License, or
	7	# (at your option) any later version.
	8	#
	9	# This program is distributed in the hope that it will be useful,
	10	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	# GNU General Public License for more details.
	13	#
	14	# You should have received a copy of the GNU General Public License
	15	# along with this program; if not, write to the Free Software
	16	# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	17
	18	# Module: TestFilespace
	19	# Author: Dilshan Angampitiya
	20	# Steven Bird (revisions)
	21	# David Coles (revisions and moved to module)
	22	# Date: 24/1/2008
	23
	24	import StringIO
	25
	26	class TestFilespace:
	27	"""
	28	Our dummy file system which is accessed by code being tested.
	29	Implemented as a dictionary which maps filenames to strings
	30	"""
	31	def __init__(self, files=None):
	32	"Initialise, optionally with filename-filedata pairs"
	33
	34	if files == None:
	35	files = {}
	36
	37	# dict mapping files to strings
	38	self._files = {}
	39	self._files.update(files)
	40	# set of file names
	41	self._modified_files = set([])
	42	# dict mapping files to stringIO objects
	43	self._open_files = {}
	44
	45	def add_file(self, filename, data):
	46	" Add a file to the filespace "
	47	self._files[filename] = data
	48
	49	def openfile(self, filename, mode='r'):
	50	""" Open a file from the filespace with the given mode.
	51	Return a StringIO subclass object with the file contents.
	52	"""
	53	# currently very messy, needs to be cleaned up
	54	# Probably most of this should be in the initialiser to the TestStringIO
	55
	56	import re
	57
	58	if filename in self._open_files:
	59	raise IOError("File already open: %s" %filename)
	60
	61	if not re.compile("[rwa][+b]{0,2}").match(mode):
	62	raise IOError("invalid mode %s" %mode)
	63
	64	## TODO: validate filename?
65
66	mode.replace("b",'')
67
68	# initialise the file properly (truncate/create if required)
69	if mode[0] == 'w':
70	self._files[filename] = ''
71	self._modified_files.add(filename)
72	elif filename not in self._files:
73	if mode[0] == 'a':
74	self._files[filename] = ''
75	self._modified_files.add(filename)
76	else:
77	raise IOError(2, "Access to file denied: %s" %filename)
78
79	# for append mode, remember the existing data
80	if mode[0] == 'a':
81	existing_data = self._files[filename]
82	else:
83	existing_data = ""
84
85	# determine what operations are allowed
86	reading_ok = (len(mode) == 2 or mode[0] == 'r')
87	writing_ok = (len(mode) == 2 or mode[0] in 'wa')
88
89	# for all writing modes, start off with blank file
90	if mode[0] == 'w':
91	initial_data = ''
92	else:
93	initial_data = self._files[filename]
94
95	file_object = TestStringIO(initial_data, filename, self, reading_ok, writing_ok, existing_data)
96	self._open_files[filename] = file_object
97
98	return file_object
99
100	def flush_all(self):
101	""" Flush all open files
102	"""
103	for file_object in self._open_files.values():
104	file_object.flush()
105
106	def updatefile(self,filename, data):
107	""" Callback function used by an open file to inform when it has been updated.
108	"""
109	if filename in self._open_files:
110	self._files[filename] = data
111	if self._open_files[filename].is_modified():
112	self._modified_files.add(filename)
113	else:
114	raise IOError(2, "Access to file denied: %s" %filename)
115
116	def closefile(self, filename):
117	""" Callback function used by an open file to inform when it has been closed.
118	"""
119	if filename in self._open_files:
120	del self._open_files[filename]
121
122	def get_modified_files(self):
123	"""" A subset of the filespace containing only those files which have been
124	modified
125	"""
126	modified_files = {}
127	for filename in self._modified_files:
128	modified_files[filename] = self._files[filename]
129
130	return modified_files
131
132	def get_open_files(self):
133	" Return the names of all open files "
134	return self._open_files.keys()
135
136	def copy(self):
137	""" Return a copy of the current filespace.
138	Only the files are copied, not the modified or open file lists.
139	"""
140	self.flush_all()
141	return TestFilespace(self._files)
142
143	class TestStringIO(StringIO.StringIO):
144	"""
145	A subclass of StringIO which acts as a file in our dummy file system
146	"""
147	def __init__(self, string, filename, filespace, reading_ok, writing_ok, existing_data):
148	""" Initialise with the filedata, file name and infomation on what ops are
149	acceptable """
150	StringIO.StringIO.__init__(self, string)
151	self._filename = filename
152	self._filespace = filespace
153	self._reading_ok = reading_ok
154	self._writing_ok = writing_ok
155	self._existing_data = existing_data
156	self._modified = False
157	self._open = True
158
159	# Override all standard file ops. Make sure that they are valid with the given
160	# permissions and if so then call the corresponding method in StringIO
161
162	def read(self, *args):
163	if not self._reading_ok:
164	raise IOError(9, "Bad file descriptor")
165	else:
166	return StringIO.StringIO.read(self, *args)
167
168	def readline(self, *args):
169	if not self._reading_ok:
170	raise IOError(9, "Bad file descriptor")
171	else:
172	return StringIO.StringIO.readline(self, *args)
173
174	def readlines(self, *args):
175	if not self._reading_ok:
176	raise IOError(9, "Bad file descriptor")
177	else:
178	return StringIO.StringIO.readlines(self, *args)
179
180	def seek(self, *args):
181	if not self._reading_ok:
182	raise IOError(9, "Bad file descriptor")
183	else:
184	return StringIO.StringIO.seek(self, *args)
185
186	def truncate(self, *args):
187	self._modified = True
188	if not self._writing_ok:
189	raise IOError(9, "Bad file descriptor")
190	else:
191	return StringIO.StringIO.truncate(self, *args)
192
193	def write(self, *args):
194	self._modified = True
195	if not self._writing_ok:
196	raise IOError(9, "Bad file descriptor")
197	else:
198	return StringIO.StringIO.write(self, *args)
199
200	def writelines(self, *args):
201	self._modified = True
202	if not self._writing_ok:
203	raise IOError(9, "Bad file descriptor")
204	else:
205	return StringIO.StringIO.writelines(self, *args)
206
207	def is_modified(self):
208	" Return true if the file has been written to, or truncated"
209	return self._modified
210
211	def flush(self):
212	" Update the contents of the filespace with the new data "
213	self._filespace.updatefile(self._filename, self._existing_data+self.getvalue())
214	return StringIO.StringIO.flush(self)
215
216	def close(self):
217	" Flush the file and close it "
218	self.flush()
219	self._filespace.closefile(self._filename)
220	return StringIO.StringIO.close(self)
221