summaryrefslogtreecommitdiffstats
path: root/Lib/dos-8x3/configpa.py
blob: 89e2d851f1b44a2b999e31977c4dea83198d2685 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
"""Configuration file parser.

A setup file consists of sections, lead by a "[section]" header,
and followed by "name: value" entries, with continuations and such in
the style of RFC 822.

The option values can contain format strings which refer to other values in
the same section, or values in a special [DEFAULT] section.

For example:

    something: %(dir)s/whatever

would resolve the "%(dir)s" to the value of dir.  All reference
expansions are done late, on demand.

Intrinsic defaults can be specified by passing them into the
ConfigParser constructor as a dictionary.

class:

ConfigParser -- responsible for for parsing a list of
                configuration files, and managing the parsed database.

    methods:

    __init__(defaults=None) -- create the parser and specify a
                               dictionary of intrinsic defaults.  The
                               keys must be strings, the values must
                               be appropriate for %()s string
                               interpolation.  Note that `__name__' is
                               always an intrinsic default; it's value
                               is the section's name.

    sections() -- return all the configuration section names, sans DEFAULT

    options(section) -- return list of configuration options for the named
                        section

    read(*filenames) -- read and parse the list of named configuration files

    get(section, option, raw=0) -- return a string value for the named
                                   option.  All % interpolations are
                                   expanded in the return values, based on
                                   the defaults passed into the constructor
                                   and the DEFAULT section.

    getint(section, options) -- like get(), but convert value to an integer

    getfloat(section, options) -- like get(), but convert value to a float

    getboolean(section, options) -- like get(), but convert value to
                                    a boolean (currently defined as 0
                                    or 1, only)
"""

import sys
import string
import re

DEFAULTSECT = "DEFAULT"



# exception classes
class Error:
    def __init__(self, msg=''):
        self._msg = msg
    def __repr__(self):
        return self._msg

class NoSectionError(Error):
    def __init__(self, section):
        Error.__init__(self, 'No section: %s' % section)
        self.section = section

class DuplicateSectionError(Error):
    def __init__(self, section):
        Error.__init__(self, "Section %s already exists" % section)
        self.section = section

class NoOptionError(Error):
    def __init__(self, option, section):
        Error.__init__(self, "No option `%s' in section: %s" %
                       (option, section))
        self.option = option
        self.section = section

class InterpolationError(Error):
    def __init__(self, reference, option, section, rawval):
        Error.__init__(self,
                       "Bad value substitution:\n"
                       "\tsection: [%s]\n"
                       "\toption : %s\n"
                       "\tkey    : %s\n"
                       "\trawval : %s\n"
                       % (section, option, reference, rawval))
        self.reference = reference
        self.option = option
        self.section = section

class MissingSectionHeaderError(Error):
    def __init__(self, filename, lineno, line):
        Error.__init__(
            self,
            'File contains no section headers.\nfile: %s, line: %d\n%s' %
            (filename, lineno, line))
        self.filename = filename
        self.lineno = lineno
        self.line = line

class ParsingError(Error):
    def __init__(self, filename):
        Error.__init__(self, 'File contains parsing errors: %s' % filename)
        self.filename = filename
        self.errors = []

    def append(self, lineno, line):
        self.errors.append((lineno, line))
        self._msg = self._msg + '\n\t[line %2d]: %s' % (lineno, line)



class ConfigParser:
    def __init__(self, defaults=None):
        self.__sections = {}
        if defaults is None:
            self.__defaults = {}
        else:
            self.__defaults = defaults

    def defaults(self):
        return self.__defaults

    def sections(self):
        """Return a list of section names, excluding [DEFAULT]"""
        # self.__sections will never have [DEFAULT] in it
        return self.__sections.keys()

    def add_section(self, section):
        """Create a new section in the configuration.

        Raise DuplicateSectionError if a section by the specified name
        already exists.
        """
        if self.__sections.has_key(section):
            raise DuplicateSectionError(section)
        self.__sections[section] = {}

    def has_section(self, section):
        """Indicate whether the named section is present in the configuration.

        The DEFAULT section is not acknowledged.
        """
        return self.__sections.has_key(section)

    def options(self, section):
        try:
            opts = self.__sections[section].copy()
        except KeyError:
            raise NoSectionError(section)
        opts.update(self.__defaults)
        return opts.keys()

    def read(self, filenames):
        """Read and parse a list of filenames."""
        if type(filenames) is type(''):
            filenames = [filenames]
        for file in filenames:
            try:
                fp = open(file, 'r')
                self.__read(fp)
            except IOError:
                pass

    def get(self, section, option, raw=0):
        """Get an option value for a given section.

        All % interpolations are expanded in the return values, based
        on the defaults passed into the constructor, unless the optional
        argument `raw' is true.

        The section DEFAULT is special.
        """
        try:
            sectdict = self.__sections[section].copy()
        except KeyError:
            if section == DEFAULTSECT:
                sectdict = {}
            else:
                raise NoSectionError(section)
        d = self.__defaults.copy()
        d.update(sectdict)
        option = string.lower(option)
        try:
            rawval = d[option]
        except KeyError:
            raise NoOptionError(option, section)
        # do the string interpolation
        if raw:
            return rawval
        try:
            return rawval % d
        except KeyError, key:
            raise InterpolationError(key, option, section, rawval)

    def __get(self, section, conv, option):
        return conv(self.get(section, option))

    def getint(self, section, option):
        return self.__get(section, string.atoi, option)

    def getfloat(self, section, option):
        return self.__get(section, string.atof, option)

    def getboolean(self, section, option):
        v = self.get(section, option)
        val = string.atoi(v)
        if val not in (0, 1):
            raise ValueError, 'Not a boolean: %s' % v
        return val

    #
    # Regular expressions for parsing section headers and options.  Note a
    # slight semantic change from the previous version, because of the use
    # of \w, _ is allowed in section header names.
    __SECTCRE = re.compile(
        r'\['                                 # [
        r'(?P<header>[-\w]+)'                 # `-', `_' or any alphanum
        r'\]'                                 # ]
        )
    __OPTCRE = re.compile(
        r'(?P<option>[-.\w]+)'                # - . _ alphanum
        r'[ \t]*[:=][ \t]*'                   # any number of space/tab,
                                              # followed by separator
                                              # (either : or =), followed
                                              # by any # space/tab
        r'(?P<value>.*)$'                     # everything up to eol
        )

    def __read(self, fp):
        """Parse a sectioned setup file.

        The sections in setup file contains a title line at the top,
        indicated by a name in square brackets (`[]'), plus key/value
        options lines, indicated by `name: value' format lines.
        Continuation are represented by an embedded newline then
        leading whitespace.  Blank lines, lines beginning with a '#',
        and just about everything else is ignored.
        """
        cursect = None                            # None, or a dictionary
        optname = None
        lineno = 0
        e = None                                  # None, or an exception
        while 1:
            line = fp.readline()
            if not line:
                break
            lineno = lineno + 1
            # comment or blank line?
            if string.strip(line) == '' or line[0] in '#;':
                continue
            if string.lower(string.split(line)[0]) == 'rem' \
               and line[0] == "r":      # no leading whitespace
                continue
            # continuation line?
            if line[0] in ' \t' and cursect is not None and optname:
                value = string.strip(line)
                if value:
                    cursect[optname] = cursect[optname] + '\n ' + value
            # a section header or option header?
            else:
                # is it a section header?
                mo = self.__SECTCRE.match(line)
                if mo:
                    sectname = mo.group('header')
                    if self.__sections.has_key(sectname):
                        cursect = self.__sections[sectname]
                    elif sectname == DEFAULTSECT:
                        cursect = self.__defaults
                    else:
                        cursect = {'__name__': sectname}
                        self.__sections[sectname] = cursect
                    # So sections can't start with a continuation line
                    optname = None
                # no section header in the file?
                elif cursect is None:
                    raise MissingSectionHeaderError(fp.name, lineno, `line`)
                # an option line?
                else:
                    mo = self.__OPTCRE.match(line)
                    if mo:
                        optname, optval = mo.group('option', 'value')
                        optname = string.lower(optname)
                        optval = string.strip(optval)
                        # allow empty values
                        if optval == '""':
                            optval = ''
                        cursect[optname] = optval
                    else:
                        # a non-fatal parsing error occurred.  set up the
                        # exception but keep going. the exception will be
                        # raised at the end of the file and will contain a
                        # list of all bogus lines
                        if not e:
                            e = ParsingError(fp.name)
                        e.append(lineno, `line`)
        # if any parsing errors occurred, raise an exception
        if e:
            raise e