xref: /openbmc/openbmc/poky/bitbake/lib/bb/parse/parse_py/ConfHandler.py (revision 96e4b4e121e0e2da1535d7d537d6a982a6ff5bc0) 
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__includeall_regexp__ = re.compile( r"include_all\s+(.+)" )
47__export_regexp__ = re.compile( r"export\s+([a-zA-Z0-9\-_+.${}/~]+)$" )
48__unset_regexp__ = re.compile( r"unset\s+([a-zA-Z0-9\-_+.${}/~]+)$" )
49__unset_flag_regexp__ = re.compile( r"unset\s+([a-zA-Z0-9\-_+.${}/~]+)\[([a-zA-Z0-9\-_+.][a-zA-Z0-9\-_+.@]+)\]$" )
50__addpylib_regexp__      = re.compile(r"addpylib\s+(.+)\s+(.+)" )
51__addfragments_regexp__  = re.compile(r"addfragments\s+(.+)\s+(.+)\s+(.+)" )
52
53def init(data):
54    return
55
56def supports(fn, d):
57    return fn[-5:] == ".conf"
58
59def include(parentfn, fns, lineno, data, error_out):
60    """
61    error_out: A string indicating the verb (e.g. "include", "inherit") to be
62    used in a ParseError that will be raised if the file to be included could
63    not be included. Specify False to avoid raising an error in this case.
64    """
65    fns = data.expand(fns)
66    parentfn = data.expand(parentfn)
67
68    # "include" or "require" accept zero to n space-separated file names to include.
69    for fn in fns.split():
70        include_single_file(parentfn, fn, lineno, data, error_out)
71
72def include_single_file(parentfn, fn, lineno, data, error_out):
73    """
74    Helper function for include() which does not expand or split its parameters.
75    """
76    if parentfn == fn: # prevent infinite recursion
77        return None
78
79    if not os.path.isabs(fn):
80        dname = os.path.dirname(parentfn)
81        bbpath = "%s:%s" % (dname, data.getVar("BBPATH"))
82        abs_fn, attempts = bb.utils.which(bbpath, fn, history=True)
83        if abs_fn and bb.parse.check_dependency(data, abs_fn):
84            logger.warning("Duplicate inclusion for %s in %s" % (abs_fn, data.getVar('FILE')))
85        for af in attempts:
86            bb.parse.mark_dependency(data, af)
87        if abs_fn:
88            fn = abs_fn
89    elif bb.parse.check_dependency(data, fn):
90        logger.warning("Duplicate inclusion for %s in %s" % (fn, data.getVar('FILE')))
91
92    try:
93        bb.parse.handle(fn, data, True)
94    except (IOError, OSError) as exc:
95        if exc.errno == errno.ENOENT:
96            if error_out:
97                raise ParseError("Could not %s file %s" % (error_out, fn), parentfn, lineno)
98            logger.debug2("CONF file '%s' not found", fn)
99        else:
100            if error_out:
101                raise ParseError("Could not %s file %s: %s" % (error_out, fn, exc.strerror), parentfn, lineno)
102            else:
103                raise ParseError("Error parsing %s: %s" % (fn, exc.strerror), parentfn, lineno)
104
105# We have an issue where a UI might want to enforce particular settings such as
106# an empty DISTRO variable. If configuration files do something like assigning
107# a weak default, it turns out to be very difficult to filter out these changes,
108# particularly when the weak default might appear half way though parsing a chain
109# of configuration files. We therefore let the UIs hook into configuration file
110# parsing. This turns out to be a hard problem to solve any other way.
111confFilters = []
112
113def handle(fn, data, include, baseconfig=False):
114    init(data)
115
116    if include == 0:
117        oldfile = None
118    else:
119        oldfile = data.getVar('FILE', False)
120
121    abs_fn = resolve_file(fn, data)
122    with open(abs_fn, 'r') as f:
123
124        statements = ast.StatementGroup()
125        lineno = 0
126        while True:
127            lineno = lineno + 1
128            s = f.readline()
129            if not s:
130                break
131            origlineno = lineno
132            origline = s
133            w = s.strip()
134            # skip empty lines
135            if not w:
136                continue
137            s = s.rstrip()
138            while s[-1] == '\\':
139                line = f.readline()
140                origline += line
141                s2 = line.rstrip()
142                lineno = lineno + 1
143                if (not s2 or s2 and s2[0] != "#") and s[0] == "#" :
144                    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))
145
146                s = s[:-1] + s2
147            # skip comments
148            if s[0] == '#':
149                continue
150            feeder(lineno, s, abs_fn, statements, baseconfig=baseconfig)
151
152    # DONE WITH PARSING... time to evaluate
153    data.setVar('FILE', abs_fn)
154    statements.eval(data)
155    if oldfile:
156        data.setVar('FILE', oldfile)
157
158    for f in confFilters:
159        f(fn, data)
160
161    return data
162
163# baseconfig is set for the bblayers/layer.conf cookerdata config parsing
164# The function is also used by BBHandler, conffile would be False
165def feeder(lineno, s, fn, statements, baseconfig=False, conffile=True):
166    m = __config_regexp__.match(s)
167    if m:
168        groupd = m.groupdict()
169        ast.handleData(statements, fn, lineno, groupd)
170        return
171
172    m = __include_regexp__.match(s)
173    if m:
174        ast.handleInclude(statements, fn, lineno, m, False)
175        return
176
177    m = __require_regexp__.match(s)
178    if m:
179        ast.handleInclude(statements, fn, lineno, m, True)
180        return
181
182    m = __includeall_regexp__.match(s)
183    if m:
184        ast.handleIncludeAll(statements, fn, lineno, m)
185        return
186
187    m = __export_regexp__.match(s)
188    if m:
189        ast.handleExport(statements, fn, lineno, m)
190        return
191
192    m = __unset_regexp__.match(s)
193    if m:
194        ast.handleUnset(statements, fn, lineno, m)
195        return
196
197    m = __unset_flag_regexp__.match(s)
198    if m:
199        ast.handleUnsetFlag(statements, fn, lineno, m)
200        return
201
202    m = __addpylib_regexp__.match(s)
203    if baseconfig and conffile and m:
204        ast.handlePyLib(statements, fn, lineno, m)
205        return
206
207    m = __addfragments_regexp__.match(s)
208    if m:
209        ast.handleAddFragments(statements, fn, lineno, m)
210        return
211
212    raise ParseError("unparsed line: '%s'" % s, fn, lineno);
213
214# Add us to the handlers list
215from bb.parse import handlers
216handlers.append({'supports': supports, 'handle': handle, 'init': init})
217del handlers
218