1"""
2   class for handling configuration data files
3
4   Reads a .conf file and obtains its metadata
5
6"""
7
8# Copyright (C) 2003, 2004  Chris Larson
9# Copyright (C) 2003, 2004  Phil Blundell
10#
11# SPDX-License-Identifier: GPL-2.0-only
12#
13
14import errno
15import re
16import os
17import bb.utils
18from bb.parse import ParseError, resolve_file, ast, logger, handle
19
20__config_regexp__  = re.compile( r"""
21    ^
22    (?P<exp>export\s+)?
23    (?P<var>[a-zA-Z0-9\-_+.${}/~:]+?)
24    (\[(?P<flag>[a-zA-Z0-9\-_+.][a-zA-Z0-9\-_+.@/]*)\])?
25
26    \s* (
27        (?P<colon>:=) |
28        (?P<lazyques>\?\?=) |
29        (?P<ques>\?=) |
30        (?P<append>\+=) |
31        (?P<prepend>=\+) |
32        (?P<predot>=\.) |
33        (?P<postdot>\.=) |
34        =
35    ) \s*
36
37    (?!'[^']*'[^']*'$)
38    (?!\"[^\"]*\"[^\"]*\"$)
39    (?P<apo>['\"])
40    (?P<value>.*)
41    (?P=apo)
42    $
43    """, re.X)
44__include_regexp__ = re.compile( r"include\s+(.+)" )
45__require_regexp__ = re.compile( r"require\s+(.+)" )
46__export_regexp__ = re.compile( r"export\s+([a-zA-Z0-9\-_+.${}/~]+)$" )
47__unset_regexp__ = re.compile( r"unset\s+([a-zA-Z0-9\-_+.${}/~]+)$" )
48__unset_flag_regexp__ = re.compile( r"unset\s+([a-zA-Z0-9\-_+.${}/~]+)\[([a-zA-Z0-9\-_+.][a-zA-Z0-9\-_+.@]+)\]$" )
49__addpylib_regexp__      = re.compile(r"addpylib\s+(.+)\s+(.+)" )
50__addfragments_regexp__  = re.compile(r"addfragments\s+(.+)\s+(.+)\s+(.+)" )
51
52def init(data):
53    return
54
55def supports(fn, d):
56    return fn[-5:] == ".conf"
57
58def include(parentfn, fns, lineno, data, error_out):
59    """
60    error_out: A string indicating the verb (e.g. "include", "inherit") to be
61    used in a ParseError that will be raised if the file to be included could
62    not be included. Specify False to avoid raising an error in this case.
63    """
64    fns = data.expand(fns)
65    parentfn = data.expand(parentfn)
66
67    # "include" or "require" accept zero to n space-separated file names to include.
68    for fn in fns.split():
69        include_single_file(parentfn, fn, lineno, data, error_out)
70
71def include_single_file(parentfn, fn, lineno, data, error_out):
72    """
73    Helper function for include() which does not expand or split its parameters.
74    """
75    if parentfn == fn: # prevent infinite recursion
76        return None
77
78    if not os.path.isabs(fn):
79        dname = os.path.dirname(parentfn)
80        bbpath = "%s:%s" % (dname, data.getVar("BBPATH"))
81        abs_fn, attempts = bb.utils.which(bbpath, fn, history=True)
82        if abs_fn and bb.parse.check_dependency(data, abs_fn):
83            logger.warning("Duplicate inclusion for %s in %s" % (abs_fn, data.getVar('FILE')))
84        for af in attempts:
85            bb.parse.mark_dependency(data, af)
86        if abs_fn:
87            fn = abs_fn
88    elif bb.parse.check_dependency(data, fn):
89        logger.warning("Duplicate inclusion for %s in %s" % (fn, data.getVar('FILE')))
90
91    try:
92        bb.parse.handle(fn, data, True)
93    except (IOError, OSError) as exc:
94        if exc.errno == errno.ENOENT:
95            if error_out:
96                raise ParseError("Could not %s file %s" % (error_out, fn), parentfn, lineno)
97            logger.debug2("CONF file '%s' not found", fn)
98        else:
99            if error_out:
100                raise ParseError("Could not %s file %s: %s" % (error_out, fn, exc.strerror), parentfn, lineno)
101            else:
102                raise ParseError("Error parsing %s: %s" % (fn, exc.strerror), parentfn, lineno)
103
104# We have an issue where a UI might want to enforce particular settings such as
105# an empty DISTRO variable. If configuration files do something like assigning
106# a weak default, it turns out to be very difficult to filter out these changes,
107# particularly when the weak default might appear half way though parsing a chain
108# of configuration files. We therefore let the UIs hook into configuration file
109# parsing. This turns out to be a hard problem to solve any other way.
110confFilters = []
111
112def handle(fn, data, include, baseconfig=False):
113    init(data)
114
115    if include == 0:
116        oldfile = None
117    else:
118        oldfile = data.getVar('FILE', False)
119
120    abs_fn = resolve_file(fn, data)
121    with open(abs_fn, 'r') as f:
122
123        statements = ast.StatementGroup()
124        lineno = 0
125        while True:
126            lineno = lineno + 1
127            s = f.readline()
128            if not s:
129                break
130            origlineno = lineno
131            origline = s
132            w = s.strip()
133            # skip empty lines
134            if not w:
135                continue
136            s = s.rstrip()
137            while s[-1] == '\\':
138                line = f.readline()
139                origline += line
140                s2 = line.rstrip()
141                lineno = lineno + 1
142                if (not s2 or s2 and s2[0] != "#") and s[0] == "#" :
143                    bb.fatal("There is a confusing multiline, partially commented expression starting on line %s of file %s:\n%s\nPlease clarify whether this is all a comment or should be parsed." % (origlineno, fn, origline))
144
145                s = s[:-1] + s2
146            # skip comments
147            if s[0] == '#':
148                continue
149            feeder(lineno, s, abs_fn, statements, baseconfig=baseconfig)
150
151    # DONE WITH PARSING... time to evaluate
152    data.setVar('FILE', abs_fn)
153    statements.eval(data)
154    if oldfile:
155        data.setVar('FILE', oldfile)
156
157    for f in confFilters:
158        f(fn, data)
159
160    return data
161
162# baseconfig is set for the bblayers/layer.conf cookerdata config parsing
163# The function is also used by BBHandler, conffile would be False
164def feeder(lineno, s, fn, statements, baseconfig=False, conffile=True):
165    m = __config_regexp__.match(s)
166    if m:
167        groupd = m.groupdict()
168        ast.handleData(statements, fn, lineno, groupd)
169        return
170
171    m = __include_regexp__.match(s)
172    if m:
173        ast.handleInclude(statements, fn, lineno, m, False)
174        return
175
176    m = __require_regexp__.match(s)
177    if m:
178        ast.handleInclude(statements, fn, lineno, m, True)
179        return
180
181    m = __export_regexp__.match(s)
182    if m:
183        ast.handleExport(statements, fn, lineno, m)
184        return
185
186    m = __unset_regexp__.match(s)
187    if m:
188        ast.handleUnset(statements, fn, lineno, m)
189        return
190
191    m = __unset_flag_regexp__.match(s)
192    if m:
193        ast.handleUnsetFlag(statements, fn, lineno, m)
194        return
195
196    m = __addpylib_regexp__.match(s)
197    if baseconfig and conffile and m:
198        ast.handlePyLib(statements, fn, lineno, m)
199        return
200
201    m = __addfragments_regexp__.match(s)
202    if m:
203        ast.handleAddFragments(statements, fn, lineno, m)
204        return
205
206    raise ParseError("unparsed line: '%s'" % s, fn, lineno);
207
208# Add us to the handlers list
209from bb.parse import handlers
210handlers.append({'supports': supports, 'handle': handle, 'init': init})
211del handlers
212