# Copyright (c) 2011-2018, Ulf Magnusson
# SPDX-License-Identifier: ISC
"""
Overview
========
Kconfiglib is a Python 2/3 library for scripting and extracting information
from Kconfig (https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt)
configuration systems.
See the homepage at https://github.com/ulfalizer/Kconfiglib for a longer
overview.
Using Kconfiglib on the Linux kernel with the Makefile targets
==============================================================
For the Linux kernel, a handy interface is provided by the
scripts/kconfig/Makefile patch, which can be applied with either 'git am' or
the 'patch' utility:
$ wget -qO- https://raw.githubusercontent.com/ulfalizer/Kconfiglib/master/makefile.patch | git am
$ wget -qO- https://raw.githubusercontent.com/ulfalizer/Kconfiglib/master/makefile.patch | patch -p1
Warning: Not passing -p1 to patch will cause the wrong file to be patched.
Please tell me if the patch does not apply. It should be trivial to apply
manually, as it's just a block of text that needs to be inserted near the other
*conf: targets in scripts/kconfig/Makefile.
Look further down for a motivation for the Makefile patch and for instructions
on how you can use Kconfiglib without it.
If you do not wish to install Kconfiglib via pip, the Makefile patch is set up
so that you can also just clone Kconfiglib into the kernel root:
$ git clone git://github.com/ulfalizer/Kconfiglib.git
$ git am Kconfiglib/makefile.patch (or 'patch -p1 < Kconfiglib/makefile.patch')
Warning: The directory name Kconfiglib/ is significant in this case, because
it's added to PYTHONPATH by the new targets in makefile.patch.
The targets added by the Makefile patch are described in the following
sections.
make [ARCH=<arch>] iscriptconfig
--------------------------------
This target gives an interactive Python prompt where a Kconfig instance has
been preloaded and is available in 'kconf'. To change the Python interpreter
used, pass PYTHONCMD=<executable> to make. The default is "python".
To get a feel for the API, try evaluating and printing the symbols in
kconf.defined_syms, and explore the MenuNode menu tree starting at
kconf.top_node by following 'next' and 'list' pointers.
The item contained in a menu node is found in MenuNode.item (note that this can
be one of the constants kconfiglib.MENU and kconfiglib.COMMENT), and all
symbols and choices have a 'nodes' attribute containing their menu nodes
(usually only one). Printing a menu node will print its item, in Kconfig
format.
If you want to look up a symbol by name, use the kconf.syms dictionary.
make scriptconfig SCRIPT=<script> [SCRIPT_ARG=<arg>]
----------------------------------------------------
This target runs the Python script given by the SCRIPT parameter on the
configuration. sys.argv[1] holds the name of the top-level Kconfig file
(currently always "Kconfig" in practice), and sys.argv[2] holds the SCRIPT_ARG
argument, if given.
See the examples/ subdirectory for example scripts.
Using Kconfiglib without the Makefile targets
=============================================
The make targets are only needed for a trivial reason: The Kbuild makefiles
export environment variables which are referenced inside the Kconfig files (via
'option env="ENV_VARIABLE"').
In practice, the only variables referenced (as of writing, and for many years)
are ARCH, SRCARCH, and KERNELVERSION. To run Kconfiglib without the Makefile
patch, do this:
$ ARCH=x86 SRCARCH=x86 KERNELVERSION=`make kernelversion` python
>>> import kconfiglib
>>> kconf = kconfiglib.Kconfig() # filename defaults to "Kconfig"
Search the top-level Makefile for "Additional ARCH settings" to see other
possibilities for ARCH and SRCARCH. Kconfiglib will print a warning if an unset
environment variable is referenced inside the Kconfig files.
Gotcha
******
It's important to set $SRCARCH even if you don't care about values and only
want to extract information from Kconfig files, because the top-level Makefile
does this (as of writing):
source "arch/$SRCARCH/Kconfig"
If $SRCARCH is not set, this expands to "arch//Kconfig", and arch/Kconfig
happens to be an existing file, giving something that appears to work but is
actually a truncated configuration. The available symbols will differ depending
on the arch as well.
Intro to symbol values
======================
Kconfiglib has the same assignment semantics as the C implementation.
Any symbol can be assigned a value by the user (via Kconfig.load_config() or
Symbol.set_value()), but this user value is only respected if the symbol is
visible, which corresponds to it (currently) being visible in the menuconfig
interface.
For symbols with prompts, the visibility of the symbol is determined by the
condition on the prompt. Symbols without prompts are never visible, so setting
a user value on them is pointless. A warning will be printed by default if
Symbol.set_value() is called on a promptless symbol. Assignments to promptless
symbols are normal within a .config file, so no similar warning will be printed
by load_config().
Dependencies from parents and 'if'/'depends on' are propagated to properties,
including prompts, so these two configurations are logically equivalent:
(1)
menu "menu"
depends on A
if B
config FOO
tristate "foo" if D
default y
depends on C
endif
endmenu
(2)
menu "menu"
depends on A
config FOO
tristate "foo" if A && B && C && D
default y if A && B && C
endmenu
In this example, A && B && C && D (the prompt condition) needs to be non-n for
FOO to be visible (assignable). If its value is m, the symbol can only be
assigned the value m: The visibility sets an upper bound on the value that can
be assigned by the user, and any higher user value will be truncated down.
'default' properties are independent of the visibility, though a 'default' will
often get the same condition as the prompt due to dependency propagation.
'default' properties are used if the symbol is not visible or has no user
value.
Symbols with no user value (or that have a user value but are not visible) and
no (active) 'default' default to n for bool/tristate symbols, and to the empty
string for other symbol types.
'select' works similarly to symbol visibility, but sets a lower bound on the
value of the symbol. The lower bound is determined by the value of the
select*ing* symbol. 'select' does not respect visibility, so non-visible
symbols can be forced to a particular (minimum) value by a select as well.
For non-bool/tristate symbols, it only matters whether the visibility is n or
non-n: m visibility acts the same as y visibility.
Conditions on 'default' and 'select' work in mostly intuitive ways. If the
condition is n, the 'default' or 'select' is disabled. If it is m, the
'default' or 'select' value (the value of the selecting symbol) is truncated
down to m.
When writing a configuration with Kconfig.write_config(), only symbols that are
visible, have an (active) default, or are selected will get written out (note
that this includes all symbols that would accept user values). Kconfiglib
matches the .config format produced by the C implementations down to the
character. This eases testing.
In Kconfiglib, the set of (currently) assignable values for a bool/tristate
symbol appear in Symbol.assignable. For other symbol types, just check if
sym.visibility is non-0 (non-n) to see whether the user value will have an
effect.
Intro to the menu tree
======================
The menu structure, as seen in e.g. menuconfig, is represented by a tree of
MenuNode objects. The top node of the configuration corresponds to an implicit
top-level menu, the title of which is shown at the top in the standard
menuconfig interface. (The title with variables expanded is available in
Kconfig.mainmenu_text in Kconfiglib.)
The top node is found in Kconfig.top_node. From there, you can visit child menu
nodes by following the 'list' pointer, and any following menu nodes by
following the 'next' pointer. Usually, a non-None 'list' pointer indicates a
menu or Choice, but menu nodes for symbols can sometimes have a non-None 'list'
pointer too due to submenus created implicitly from dependencies.
MenuNode.item is either a Symbol or a Choice object, or one of the constants
MENU and COMMENT. The prompt of the menu node can be found in MenuNode.prompt,
which also holds the title for menus and comments. For Symbol and Choice,
MenuNode.help holds the help text (if any, otherwise None).
Most symbols will only have a single menu node. A symbol defined in multiple
locations will have one menu node for each location. The list of menu nodes for
a Symbol or Choice can be found in the Symbol/Choice.nodes attribute.
Note that prompts and help texts for symbols and choices are stored in their
menu node(s) rather than in the Symbol or Choice objects themselves. This makes
it possible to define a symbol in multiple locations with a different prompt or
help text in each location. To get the help text or prompt for a symbol with a
single menu node, do sym.nodes[0].help and sym.nodes[0].prompt, respectively.
The prompt is a (text, condition) tuple, where condition determines the
visibility (see 'Intro to expressions' below).
This organization mirrors the C implementation. MenuNode is called
'struct menu' there, but I thought "menu" was a confusing name.
It is possible to give a Choice a name and define it in multiple locations,
hence why Choice.nodes is also a list. In practice, you're unlikely to ever see
a choice defined in more than one location. I don't think I've even seen a
named choice outside of the test suite.
Intro to expressions
====================
Expressions can be evaluated with the expr_value() function and printed with
the expr_str() function (these are used internally as well). Evaluating an
expression always yields a tristate value, where n, m, and y are represented as
0, 1, and 2, respectively.
The following table should help you figure out how expressions are represented.
A, B, C, ... are symbols (Symbol instances), NOT is the kconfiglib.NOT
constant, etc.
Expression Representation
---------- --------------
A A
"A" A (constant symbol)
!A (NOT, A)
A && B (AND, A, B)
A && B && C (AND, A, (AND, B, C))
A || B (OR, A, B)
A || (B && C && D) (OR, A, (AND, B, (AND, C, D)))
A = B (EQUAL, A, B)
A != "foo" (UNEQUAL, A, foo (constant symbol))
A && B = C && D (AND, A, (AND, (EQUAL, B, C), D))
n Kconfig.n (constant symbol)
m Kconfig.m (constant symbol)
y Kconfig.y (constant symbol)
"y" Kconfig.y (constant symbol)
Strings like "foo" in 'default "foo"' or 'depends on SYM = "foo"' are
represented as constant symbols, so the only values that appear in expressions
are symbols***. This mirrors the C implementation.
***For choice symbols, the parent Choice will appear in expressions as well,
but it's usually invisible as the value interfaces of Symbol and Choice are
identical. This mirrors the C implementation and makes different choice modes
"just work".
Manual evaluation examples:
- The value of A && B is min(A.tri_value, B.tri_value)
- The value of A || B is max(A.tri_value, B.tri_value)
- The value of !A is 2 - A.tri_value
- The value of A = B is 2 (y) if A.str_value == B.str_value, and 0 (n)
otherwise. Note that str_value is used here instead of tri_value.
For constant (as well as undefined) symbols, str_value matches the name of
the symbol. This mirrors the C implementation and explains why
'depends on SYM = "foo"' above works as expected.
n/m/y are automatically converted to the corresponding constant symbols
"n"/"m"/"y" (Kconfig.n/m/y) during parsing.
Kconfig.const_syms is a dictionary like Kconfig.syms but for constant symbols.
If a condition is missing (e.g., <cond> when the 'if <cond>' is removed from
'default A if <cond>'), it is actually Kconfig.y. The standard __str__()
functions just avoid printing 'if y' conditions to give cleaner output.
Feedback
========
Send bug reports, suggestions, and questions to ulfalizer a.t Google's email
service, or open a ticket on the GitHub page.
"""
import errno
import glob
import os
import platform
import re
import sys
# File layout:
#
# Public classes
# Public functions
# Internal functions
# Public global constants
# Internal global constants
# Line length: 79 columns
#
# Public classes
#
class Kconfig(object):
"""
Represents a Kconfig configuration, e.g. for x86 or ARM. This is the set of
symbols, choices, and menu nodes appearing in the configuration. Creating
any number of Kconfig objects (including for different architectures) is
safe. Kconfiglib doesn't keep any global state.
The following attributes are available. They should be treated as
read-only, and some are implemented through @property magic.
syms:
A dictionary with all symbols in the configuration, indexed by name. Also
includes all symbols that are referenced in expressions but never
defined, except for constant (quoted) symbols.
const_syms:
A dictionary like 'syms' for constant (quoted) symbols.
named_choices:
A dictionary like 'syms' for named choices (choice FOO). This is for
completeness. I've never seen a named choice outside of the test suite.
defined_syms:
A list with all defined symbols, in the same order as they appear in the
Kconfig files. Provided as a convenience.
n/m/y:
The predefined constant symbols n/m/y. Also available in const_syms.
modules:
The Symbol instance for the modules symbol. Currently hardcoded to
MODULES, which is backwards compatible. Kconfiglib will warn if
'option modules' is set on some other symbol. Tell me if you need proper
'option modules' support.
'modules' is never None. If the MODULES symbol is not explicitly defined,
its tri_value will be 0 (n), as expected.
A simple way to enable modules is to do 'kconf.modules.set_value(2)'
(provided the MODULES symbol is defined and visible). Modules are
disabled by default in the kernel Kconfig files as of writing, though
nearly all defconfig files enable them (with 'CONFIG_MODULES=y').
defconfig_list:
The Symbol instance for the 'option defconfig_list' symbol, or None if no
defconfig_list symbol exists. The defconfig filename derived from this
symbol can be found in Kconfig.defconfig_filename.
defconfig_filename:
The filename given by the defconfig_list symbol. This is taken from the
first 'default' with a satisfied condition where the specified file
exists (can be opened for reading). If a defconfig file foo/defconfig is
not found and $srctree was set when the Kconfig was created,
$srctree/foo/defconfig is looked up as well.
References to Kconfig symbols ("$FOO") in the 'default' properties of the
defconfig_filename symbol are are expanded before the file is looked up.
'defconfig_filename' is None if either no defconfig_list symbol exists,
or if the defconfig_list symbol has no 'default' with a satisfied
condition that specifies a file that exists.
Gotcha: scripts/kconfig/Makefile might pass --defconfig=<defconfig> to
scripts/kconfig/conf when running e.g. 'make defconfig'. This option
overrides the defconfig_list symbol, meaning defconfig_filename might not
always match what 'make defconfig' would use.
top_node:
The menu node (see the MenuNode class) of the implicit top-level menu.
Acts as the root of the menu tree.
mainmenu_text:
The prompt (title) of the top_node menu, with Kconfig variable references
("$FOO") expanded. Defaults to "Linux Kernel Configuration" (like in the
C tools). Can be changed with the 'mainmenu' statement (see
kconfig-language.txt).
srctree:
The value of the $srctree environment variable when the configuration was
loaded, or None if $srctree wasn't set. Kconfig and .config files are
looked up relative to $srctree if they are not found in the base path
(unless absolute paths are used). This is used to support out-of-tree
builds. The C tools use this environment variable in the same way.
Changing $srctree after creating the Kconfig instance has no effect. Only
the value when the configuration is loaded matters. This avoids surprises
if multiple configurations are loaded with different values for $srctree.
config_prefix:
The value of the $CONFIG_ environment variable when the configuration was
loaded. This is the prefix used (and expected) on symbol names in .config
files and C headers. Defaults to "CONFIG_". Used in the same way in the C
tools.
Like for srctree, only the value of $CONFIG_ when the configuration is
loaded matters.
"""
__slots__ = (
"_choices",
"_print_undef_assign",
"_print_redun_assign",
"_print_warnings",
"_set_re_match",
"_unset_re_match",
"_warn_no_prompt",
"config_prefix",
"const_syms",
"defconfig_list",
"defined_syms",
"m",
"modules",
"n",
"named_choices",
"srctree",
"syms",
"top_node",
"y",
# Parsing-related
"_parsing_kconfigs",
"_file",
"_filename",
"_linenr",
"_filestack",
"_line",
"_saved_line",
"_tokens",
"_tokens_i",
"_has_tokens",
)
#
# Public interface
#
def __init__(self, filename="Kconfig", warn=True):
"""
Creates a new Kconfig object by parsing Kconfig files. Raises
KconfigSyntaxError on syntax errors. Note that Kconfig files are not
the same as .config files (which store configuration symbol values).
filename (default: "Kconfig"):
The base Kconfig file. For the Linux kernel, you'll want "Kconfig"
from the top-level directory, as environment variables will make sure
the right Kconfig is included from there (arch/$SRCARCH/Kconfig as of
writing).
If you are using Kconfiglib via 'make scriptconfig', the filename of
the base base Kconfig file will be in sys.argv[1]. It's currently
always "Kconfig" in practice.
The $srctree environment variable is used to look up Kconfig files if
set. See the class documentation.
warn (default: True):
True if warnings related to this configuration should be printed to
stderr. This can be changed later with
Kconfig.enable/disable_warnings(). It is provided as a constructor
argument since warnings might be generated during parsing.
"""
self.srctree = os.environ.get("srctree")
self.config_prefix = os.environ.get("CONFIG_")
if self.config_prefix is None:
self.config_prefix = "CONFIG_"
# Regular expressions for parsing .config files, with the match()
# method assigned directly as a small optimization (microscopic in this
# case, but it's consistent with the other regexes)
self._set_re_match = \
re.compile(r"{}([^=]+)=(.*)".format(self.config_prefix),
_RE_ASCII).match
self._unset_re_match = \
re.compile(r"# {}([^ ]+) is not set".format(self.config_prefix),
_RE_ASCII).match
self._print_warnings = warn
self._print_undef_assign = False
self._print_redun_assign = True
self.syms = {}
self.const_syms = {}
self.defined_syms = []
self.named_choices = {}
# Used for quickly invalidating all choices
self._choices = []
for nmy in "n", "m", "y":
sym = Symbol()
sym.kconfig = self
sym.name = nmy
sym.is_constant = True
sym.orig_type = TRISTATE
sym._cached_tri_val = STR_TO_TRI[nmy]
self.const_syms[nmy] = sym
self.n = self.const_syms["n"]
self.m = self.const_syms["m"]
self.y = self.const_syms["y"]
# Make n/m/y well-formed symbols
for nmy in "n", "m", "y":
sym = self.const_syms[nmy]
sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n
# This is used to determine whether previously unseen symbols should be
# registered. They shouldn't be if we parse expressions after parsing,
# as part of Kconfig.eval_string().
self._parsing_kconfigs = True
self.modules = self._lookup_sym("MODULES")
self.defconfig_list = None
# The only predefined symbol besides n/m/y. DEFCONFIG_LIST uses this as
# of writing.
uname_sym = self._lookup_const_sym("UNAME_RELEASE")
uname_sym.orig_type = STRING
# env_var doubles as the SYMBOL_AUTO flag from the C implementation, so
# just set it to something. The naming breaks a bit here.
uname_sym.env_var = "<uname release>"
uname_sym.defaults.append(
(self._lookup_const_sym(platform.uname()[2]), self.y))
self.syms["UNAME_RELEASE"] = uname_sym
self.top_node = MenuNode()
self.top_node.kconfig = self
self.top_node.item = MENU
self.top_node.visibility = self.y
self.top_node.prompt = ("Linux Kernel Configuration", self.y)
self.top_node.parent = None
self.top_node.dep = self.y
self.top_node.filename = filename
self.top_node.linenr = 1
# Parse the Kconfig files
# These implement a single line of "unget" for the parser
self._saved_line = None
self._has_tokens = False
# Keeps track of the location in the parent Kconfig files. Kconfig
# files usually source other Kconfig files.
self._filestack = []
# The current parsing location
self._filename = filename
self._linenr = 0
self._file = self._open(filename)
self._parse_block(None, # end_token
self.top_node, # parent
self.y, # visible_if_deps
self.top_node) # prev_node
self.top_node.list = self.top_node.next
self.top_node.next = None
self._parsing_kconfigs = False
# Do various post-processing of the menu tree
_finalize_tree(self.top_node)
# Build Symbol._dependents for all symbols
self._build_dep()
self._warn_no_prompt = True
@property
def mainmenu_text(self):
"""
See the class documentation.
"""
return self._expand_syms(self.top_node.prompt[0])
@property
def defconfig_filename(self):
"""
See the class documentation.
"""
if not self.defconfig_list:
return None
for filename, cond in self.defconfig_list.defaults:
if expr_value(cond):
try:
with self._open(self._expand_syms(filename.str_value)) as f:
return f.name
except IOError:
continue
return None
def load_config(self, filename, replace=True):
"""
Loads symbol values from a file in the .config format. Equivalent to
calling Symbol.set_value() to set each of the values.
"# CONFIG_FOO is not set" within a .config file sets the user value of
FOO to n. The C tools work the same way.
The Symbol.user_value attribute can be inspected afterwards to see what
value the symbol was assigned in the .config file (if any). The user
value might differ from Symbol.str/tri_value if there are unsatisfied
dependencies.
filename:
The file to load. Respects $srctree if set (see the class
documentation).
replace (default: True):
True if all existing user values should be cleared before loading the
.config.
"""
# Disable the warning about assigning to symbols without prompts. This
# is normal and expected within a .config file.
self._warn_no_prompt = False
# This stub only exists to make sure _warn_no_prompt gets reenabled
try:
self._load_config(filename, replace)
finally:
self._warn_no_prompt = True
def _load_config(self, filename, replace):
with self._open(filename) as f:
if replace:
# If we're replacing the configuration, keep track of which
# symbols and choices got set so that we can unset the rest
# later. This avoids invalidating everything and is faster.
# Another benefit is that invalidation must be rock solid for
# it to work, making it a good test.
for sym in self.defined_syms:
sym._was_set = False
for choice in self._choices:
choice._was_set = False
# Small optimizations
set_re_match = self._set_re_match
unset_re_match = self._unset_re_match
syms = self.syms
for linenr, line in enumerate(f, 1):
# The C tools ignore trailing whitespace
line = line.rstrip()
set_match = set_re_match(line)
if set_match:
name, val = set_match.groups()
if name not in syms:
self._warn_undef_assign_load(name, val, filename,
linenr)
continue
sym = syms[name]
if not sym.nodes:
self._warn_undef_assign_load(name, val, filename,
linenr)
continue
if sym.orig_type in (BOOL, TRISTATE):
# The C implementation only checks the first character
# to the right of '=', for whatever reason
if not ((sym.orig_type == BOOL and
val.startswith(("n", "y"))) or \
(sym.orig_type == TRISTATE and
val.startswith(("n", "m", "y")))):
self._warn("'{}' is not a valid value for the {} "
"symbol {}. Assignment ignored."
.format(val, TYPE_TO_STR[sym.orig_type],
_name_and_loc_str(sym)))
continue
val = val[0]
if sym.choice and val != "n":
# During .config loading, we infer the mode of the
# choice from the kind of values that are assigned
# to the choice symbols
prev_mode = sym.choice.user_value
if prev_mode is not None and \
TRI_TO_STR[prev_mode] != val:
self._warn("both m and y assigned to symbols "
"within the same choice",
filename, linenr)
# Set the choice's mode
sym.choice.set_value(val)
elif sym.orig_type == STRING:
string_match = _conf_string_re_match(val)
if not string_match:
self._warn("Malformed string literal in "
"assignment to {}. Assignment ignored."
.format(_name_and_loc_str(sym)),
filename, linenr)
continue
val = unescape(string_match.group(1))
else:
unset_match = unset_re_match(line)
if not unset_match:
continue
name = unset_match.group(1)
if name not in syms:
self._warn_undef_assign_load(name, "n", filename,
linenr)
continue
sym = syms[name]
if sym.orig_type not in (BOOL, TRISTATE):
continue
val = "n"
# Done parsing the assignment. Set the value.
if sym._was_set:
# Use strings for bool/tristate user values in the warning
if sym.orig_type in (BOOL, TRISTATE):
display_user_val = TRI_TO_STR[sym.user_value]
else:
display_user_val = sym.user_value
warn_msg = '{} set more than once. Old value: "{}", new value: "{}".'.format(
_name_and_loc_str(sym), display_user_val, val
)
if display_user_val == val:
self._warn_redun_assign(warn_msg, filename, linenr)
else:
self._warn( warn_msg, filename, linenr)
sym.set_value(val)
if replace:
# If we're replacing the configuration, unset the symbols that
# didn't get set
for sym in self.defined_syms:
if not sym._was_set:
sym.unset_value()
for choice in self._choices:
if not choice._was_set:
choice.unset_value()
def write_autoconf(self, filename,
header="/* Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib) */\n"):
r"""
Writes out symbol values as a C header file, matching the format used
by include/generated/autoconf.h in the kernel.
The ordering of the #defines matches the one generated by
write_config(). The order in the C implementation depends on the hash
table implementation as of writing, and so won't match.
filename:
Self-explanatory.
header (default: "/* Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib) */\n"):
Text that will be inserted verbatim at the beginning of the file. You
would usually want it enclosed in '/* */' to make it a C comment,
and include a final terminating newline.
"""
with open(filename, "w") as f:
# Small optimization
write = f.write
write(header)
# Avoid duplicates -- see write_config()
for sym in self.defined_syms:
sym._written = False
for sym in self.defined_syms:
if not sym._written:
# Note: _write_to_conf is determined when the value is
# calculated. This is a hidden function call due to
# property magic.
val = sym.str_value
if sym._write_to_conf:
if sym.orig_type in (BOOL, TRISTATE):
if val != "n":
write("#define {}{}{} 1\n"
.format(self.config_prefix, sym.name,
"_MODULE" if val == "m" else ""))
elif sym.orig_type == STRING:
write('#define {}{} "{}"\n'
.format(self.config_prefix, sym.name,
escape(val)))
elif sym.orig_type in (INT, HEX):
if sym.orig_type == HEX and \
not val.startswith(("0x", "0X")):
val = "0x" + val
write("#define {}{} {}\n"
.format(self.config_prefix, sym.name, val))
else:
_internal_error("Internal error while creating C "
'header: unknown type "{}".'
.format(sym.orig_type))
sym._written = True
def write_config(self, filename,
header="# Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib)\n"):
r"""
Writes out symbol values in the .config format. The format matches the
C implementation, including ordering.
Symbols appear in the same order in generated .config files as they do
in the Kconfig files. For symbols defined in multiple locations, a
single assignment is written out corresponding to the first location
where the symbol is defined.
See the 'Intro to symbol values' section in the modules docstring to
understand which symbols get written out.
filename:
Self-explanatory.
header (default: "# Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib)\n"):
Text that will be inserted verbatim at the beginning of the file. You
would usually want each line to start with '#' to make it a comment,
and include a final terminating newline.
"""
with open(filename, "w") as f:
# Small optimization
write = f.write
write(header)
# Symbol._written is set to True when a symbol config string is
# fetched, so that symbols defined in multiple locations only get
# one .config entry. We reset it prior to writing out a new
# .config. It only needs to be reset for defined symbols, because
# undefined symbols will never be written out (because they do not
# appear in the menu tree rooted at Kconfig.top_node).
#
# The C tools reuse _write_to_conf for this, but we cache
# _write_to_conf together with the value and don't invalidate
# cached values when writing .config files, so that won't work.
for sym in self.defined_syms:
sym._written = False
node = self.top_node.list
if not node:
# Empty configuration
return
while 1:
item = node.item
if isinstance(item, Symbol):
if not item._written:
config_string = item.config_string
if config_string:
write(config_string)
item._written = True
elif expr_value(node.dep) and \
((item == MENU and expr_value(node.visibility)) or
item == COMMENT):
write("\n#\n# {}\n#\n".format(node.prompt[0]))
# Iterative tree walk using parent pointers
if node.list:
node = node.list
elif node.next:
node = node.next
else:
while node.parent:
node = node.parent
if node.next:
node = node.next
break
else:
return
def eval_string(self, s):
"""
Returns the tristate value of the expression 's', represented as 0, 1,
and 2 for n, m, and y, respectively. Raises KconfigSyntaxError if
syntax errors are detected in 's'. Warns if undefined symbols are
referenced.
As an example, if FOO and BAR are tristate symbols at least one of
which has the value y, then config.eval_string("y && (FOO || BAR)")
returns 2 (y).
To get the string value of non-bool/tristate symbols, use
Symbol.str_value. eval_string() always returns a tristate value, and
all non-bool/tristate symbols have the tristate value 0 (n).
The expression parsing is consistent with how parsing works for
conditional ('if ...') expressions in the configuration, and matches
the C implementation. m is rewritten to 'm && MODULES', so
eval_string("m") will return 0 (n) unless modules are enabled.
"""
# The parser is optimized to be fast when parsing Kconfig files (where
# an expression can never appear at the beginning of a line). We have
# to monkey-patch things a bit here to reuse it.
self._filename = None
self._line = "if " + s
self._tokenize()
# Remove the "if " to avoid giving confusing error messages
self._line = s
# Remove the _T_IF token
del self._tokens[0]
return expr_value(self._parse_expr(True)) # transform_m
def unset_values(self):
"""
Resets the user values of all symbols, as if Kconfig.load_config() or
Symbol.set_value() had never been called.
"""
self._warn_no_prompt = False
try:
# set_value() already rejects undefined symbols, and they don't
# need to be invalidated (because their value never changes), so we
# can just iterate over defined symbols
for sym in self.defined_syms:
sym.unset_value()
for choice in self._choices:
choice.unset_value()
finally:
self._warn_no_prompt = True
def enable_warnings(self):
"""
See Kconfig.__init__().
"""
self._print_warnings = True
def disable_warnings(self):
"""
See Kconfig.__init__().
"""
self._print_warnings = False
def enable_undef_warnings(self):
"""
Enables warnings for assignments to undefined symbols. Printed to
stderr. Disabled by default since they tend to be spammy for Kernel
configurations (and mostly suggests cleanups).
"""
self._print_undef_assign = True
def disable_undef_warnings(self):
"""
See enable_undef_assign().
"""
self._print_undef_assign = False
def enable_redun_warnings(self):
"""
Enables warnings for redundant assignments to symbols. Printed to
stderr. Enabled by default.
"""
self._print_redun_assign = True
def disable_redun_warnings(self):
"""
See enable_redun_warnings().
"""
self._print_redun_assign = False
def __repr__(self):
"""
Returns a string with information about the Kconfig object when it is
evaluated on e.g. the interactive Python prompt.
"""
return "<{}>".format(", ".join((
"configuration with {} symbols".format(len(self.syms)),
'main menu prompt "{}"'.format(self.mainmenu_text),
"srctree not set" if self.srctree is None else
'srctree "{}"'.format(self.srctree),
'config symbol prefix "{}"'.format(self.config_prefix),
"warnings " + ("enabled" if self._print_warnings else "disabled"),
"undef. symbol assignment warnings " +
("enabled" if self._print_undef_assign else "disabled"),
"redundant symbol assignment warnings " +
("enabled" if self._print_redun_assign else "disabled")
)))
#
# Private methods
#
#
# File reading
#
def _resolve(self, filename, globbing):
"""
First tries with 'filename', then '$srctree/filename' if $srctree
was set when the configuration was loaded.
"""
if os.path.isfile(filename):
return [filename]
if not os.path.isabs(filename) and self.srctree is not None:
filename = os.path.join(self.srctree, filename)
if os.path.isfile(filename):
return [filename]
if globbing:
# Try globbing
files = glob.glob(filename)
# Glob results have an arbitrary order, so sort them to
# have consistent results across platforms.
return sorted(files)
raise IOError(
"Could not find '{}'. Perhaps the $srctree "
"environment variable (which was {}) is set incorrectly. Note "
"that the current value of $srctree is saved when the Kconfig "
"instance is created (for consistency and to cleanly "
"separate instances)."
.format(filename,
"unset" if self.srctree is None else
'"{}"'.format(self.srctree)))
def _open(self, filename):
"""
Normalize the filename based on $srctree
"""
filename = self._resolve(filename, False)[0]
try:
return open(filename, _UNIVERSAL_NEWLINES_MODE)
except IOError as e:
raise IOError(
"Could not open '{}' ({}: {})."
.format(filename, errno.errorcode[e.errno], e.strerror))
def _enter_file(self, filename):
"""
Jumps to the beginning of a sourced Kconfig file, saving the previous
position and file object.
"""
# Check for recursive 'source'
for _, name, _ in self._filestack:
if name == filename:
# KconfigParseError might have been a better name, but too late
raise KconfigSyntaxError(
"\n{}:{}: Recursive 'source' of '{}' detected. Check that "
"environment variables are set correctly.\n"
"Backtrace:\n{}"
.format(self._filename, self._linenr, filename,
"\n".join("{}:{}".format(name, linenr)
for _, name, linenr
in reversed(self._filestack))))
self._filestack.append((self._file, self._filename, self._linenr))
try:
self._file = self._open(filename)
except IOError as e:
# Extend the error message a bit in this case
raise IOError(
"{}:{}: {} Also note that e.g. $FOO in a 'source' "
"statement does not refer to the environment "
"variable FOO, but rather to the Kconfig Symbol FOO "
"(which would commonly have 'option env=\"FOO\"' in "
"its definition)."
.format(self._filename, self._linenr, str(e)))
self._filename = filename
self._linenr = 0
def _leave_file(self):
"""
Returns from a Kconfig file to the file that sourced it.
"""
self._file.close()
self._file, self._filename, self._linenr = self._filestack.pop()
def _next_line(self):
"""
Fetches and tokenizes the next line from the current Kconfig file.
Returns False at EOF and True otherwise.
"""
# _saved_line provides a single line of "unget", currently only used
# for help texts.
#
# This also works as expected if _saved_line is "", indicating EOF:
# "" is falsy, and readline() returns "" over and over at EOF.
if self._saved_line:
self._line = self._saved_line
self._saved_line = None
else:
self._line = self._file.readline()
if not self._line:
return False
self._linenr += 1
# Handle line joining
while self._line.endswith("\\\n"):
self._line = self._line[:-2] + self._file.readline()
self._linenr += 1
self._tokenize()
return True
#
# Tokenization
#
def _lookup_sym(self, name):
"""
Fetches the symbol 'name' from the symbol table, creating and
registering it if it does not exist. If '_parsing_kconfigs' is False,
it means we're in eval_string(), and new symbols won't be registered.
"""
if name in self.syms:
return self.syms[name]
sym = Symbol()
sym.kconfig = self
sym.name = name
sym.is_constant = False
sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n
if self._parsing_kconfigs:
self.syms[name] = sym
else:
self._warn("no symbol {} in configuration".format(name))
return sym
def _lookup_const_sym(self, name):
"""
Like _lookup_sym(), for constant (quoted) symbols
"""
if name in self.const_syms:
return self.const_syms[name]
sym = Symbol()
sym.kconfig = self
sym.name = name
sym.is_constant = True
sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n
if self._parsing_kconfigs:
self.const_syms[name] = sym
return sym
def _tokenize(self):
"""
Parses Kconfig._line, putting the tokens in Kconfig._tokens. Registers
any new symbols encountered with _lookup(_const)_sym().
Tries to be reasonably speedy by processing chunks of text via regexes
and string operations where possible. This is the biggest hotspot
during parsing.
"""
s = self._line
# Token index (minus one). Set for later -- not further updated here.
self._tokens_i = -1
# See comment at _initial_token_re_match definition
initial_token_match = _initial_token_re_match(s)
if not initial_token_match:
self._tokens = (None,)
return
# Tricky implementation detail: While parsing a token, 'token' refers
# to the previous token. See _STRING_LEX for why this is needed.
token = _get_keyword(initial_token_match.group(1))
if token == _T_HELP:
# Avoid junk after "help", e.g. "---", being registered as a
# symbol
self._tokens = (token, None)
return
if token is None:
self._parse_error("expected keyword as first token")
self._tokens = [token]
# The current index in the string being tokenized
i = initial_token_match.end()
# Main tokenization loop (for tokens past the first one)
while i < len(s):
# Test for an identifier/keyword first. This is the most common
# case.
id_keyword_match = _id_keyword_re_match(s, i)
if id_keyword_match:
# We have an identifier or keyword
# Jump past it
i = id_keyword_match.end()
# Check what it is. lookup_sym() will take care of allocating
# new symbols for us the first time we see them. Note that
# 'token' still refers to the previous token.
name = id_keyword_match.group(1)
keyword = _get_keyword(name)
if keyword is not None:
# It's a keyword
token = keyword
elif token not in _STRING_LEX:
# It's a non-const symbol, except we translate n, m, and y
# into the corresponding constant symbols, like the C
# implementation
token = self.const_syms[name] \
if name in ("n", "m", "y") else \
self._lookup_sym(name)
else:
# It's a case of missing quotes. For example, the
# following is accepted:
#
# menu unquoted_title
#
# config A
# tristate unquoted_prompt
#
# endmenu
token = name
else:
# Not keyword/non-const symbol
# Note: _id_keyword_match and _initial_token_match strip
# trailing whitespace, making it safe to assume s[i] is the
# start of a token here. We manually strip trailing whitespace
# below as well.
#
# An old version stripped whitespace in this spot instead, but
# that leads to some redundancy and would cause
# _id_keyword_match to be tried against just "\n" fairly often
# (because file.readlines() keeps newlines).
c = s[i]
i += 1
if c in "\"'":
# String literal/constant symbol
if "\\" not in s:
# Fast path: If the line contains no backslashes, we
# can just find the matching quote.
end = s.find(c, i)
if end == -1:
self._parse_error("unterminated string")
val = s[i:end]
i = end + 1
else:
# Slow path for lines with backslashes (very rare,
# performance irrelevant)
quote = c
val = ""
while 1:
if i >= len(s):
self._parse_error("unterminated string")
c = s[i]
if c == quote:
break
if c == "\\":
if i + 1 >= len(s):
self._parse_error("unterminated string")
val += s[i + 1]
i += 2
else:
val += c
i += 1
i += 1
# This is the only place where we don't survive with a
# single token of lookback: 'option env="FOO"' does not
# refer to a constant symbol named "FOO".
token = val \
if token in _STRING_LEX or \
self._tokens[0] == _T_OPTION else \
self._lookup_const_sym(val)
elif c == "&":
# Invalid characters are ignored (backwards-compatible)
if i >= len(s) or s[i] != "&":
continue
token = _T_AND
i += 1
elif c == "|":
# Invalid characters are ignored (backwards-compatible)
if i >= len(s) or s[i] != "|":
continue
token = _T_OR
i += 1
elif c == "!":
if i < len(s) and s[i] == "=":
token = _T_UNEQUAL
i += 1
else:
token = _T_NOT
elif c == "=":
token = _T_EQUAL
elif c == "(":
token = _T_OPEN_PAREN
elif c == ")":
token = _T_CLOSE_PAREN
elif c == "#":
break
# Very rare
elif c == "<":
if i < len(s) and s[i] == "=":
token = _T_LESS_EQUAL
i += 1
else:
token = _T_LESS
# Very rare
elif c == ">":
if i < len(s) and s[i] == "=":
token = _T_GREATER_EQUAL
i += 1
else:
token = _T_GREATER
else:
# Invalid characters are ignored (backwards-compatible)
continue
# Skip trailing whitespace
while i < len(s) and s[i].isspace():
i += 1
self._tokens.append(token)
# None-terminating token streams makes the token fetching functions
# simpler/faster
self._tokens.append(None)
def _next_token(self):
self._tokens_i += 1
return self._tokens[self._tokens_i]
def _peek_token(self):
return self._tokens[self._tokens_i + 1]
# The functions below are just _next_token() with extra syntax checking.
# Inlining _next_token() and _peek_token() into them saves a few % of
# parsing time.
#
# See the 'Intro to expressions' section for what a constant symbol is.
def _expect_sym(self):
self._tokens_i += 1
token = self._tokens[self._tokens_i]
if not isinstance(token, Symbol):
self._parse_error("expected symbol")
return token
def _expect_nonconst_sym(self):
self._tokens_i += 1
token = self._tokens[self._tokens_i]
if not isinstance(token, Symbol) or token.is_constant:
self._parse_error("expected nonconstant symbol")
return token
def _expect_nonconst_sym_and_eol(self):
self._tokens_i += 1
token = self._tokens[self._tokens_i]
if not isinstance(token, Symbol) or token.is_constant:
self._parse_error("expected nonconstant symbol")
if self._tokens[self._tokens_i + 1] is not None:
self._parse_error("extra tokens at end of line")
return token
def _expect_str(self):
self._tokens_i += 1
token = self._tokens[self._tokens_i]
if not isinstance(token, str):
self._parse_error("expected string")
return token
def _expect_str_and_eol(self):
self._tokens_i += 1
token = self._tokens[self._tokens_i]
if not isinstance(token, str):
self._parse_error("expected string")
if self._tokens[self._tokens_i + 1] is not None:
self._parse_error("extra tokens at end of line")
return token
def _check_token(self, token):
"""
If the next token is 'token', removes it and returns True.
"""
if self._tokens[self._tokens_i + 1] == token:
self._tokens_i += 1
return True
return False
#
# Parsing
#
def _make_and(self, e1, e2):
"""
Constructs an AND (&&) expression. Performs trivial simplification.
"""
if e1 is self.y:
return e2
if e2 is self.y:
return e1
if e1 is self.n or e2 is self.n:
return self.n
return (AND, e1, e2)
def _make_or(self, e1, e2):
"""
Constructs an OR (||) expression. Performs trivial simplification.
"""
if e1 is self.n:
return e2
if e2 is self.n:
return e1
if e1 is self.y or e2 is self.y:
return self.y
return (OR, e1, e2)
def _parse_block(self, end_token, parent, visible_if_deps, prev_node):
"""
Parses a block, which is the contents of either a file or an if, menu,
or choice statement.
end_token:
The token that ends the block, e.g. _T_ENDIF ("endif") for ifs. None
for files.
parent:
The parent menu node, corresponding to a menu, Choice, or 'if'. 'if's
are flattened after parsing.
visible_if_deps:
'visible if' dependencies from enclosing menus. Propagated to Symbol
and Choice prompts.
prev_node:
The previous menu node. New nodes will be added after this one (by
modifying their 'next' pointer).
prev_node is reused to parse a list of child menu nodes (for a menu
or Choice): After parsing the children, the 'next' pointer is
assigned to the 'list' pointer to "tilt up" the children above the
node.
Returns the final menu node in the block (or prev_node if the block is
empty). This allows chaining.
"""
# We might already have tokens from parsing a line to check if it's a
# property and discovering it isn't. self._has_tokens functions as a
# kind of "unget".
while self._has_tokens or self._next_line():
self._has_tokens = False
t0 = self._next_token()
if t0 is None:
continue
if t0 in (_T_CONFIG, _T_MENUCONFIG):
# The tokenizer allocates Symbol objects for us
sym = self._expect_nonconst_sym_and_eol()
self.defined_syms.append(sym)
node = MenuNode()
node.kconfig = self
node.item = sym
node.help = node.list = None
node.parent = parent
node.filename = self._filename
node.linenr = self._linenr
node.is_menuconfig = (t0 == _T_MENUCONFIG)
sym.nodes.append(node)
self._parse_properties(node, visible_if_deps)
if node.is_menuconfig and not node.prompt:
self._warn("the menuconfig symbol {} has no prompt"
.format(_name_and_loc_str(node.item)))
# Tricky Python semantics: This assign prev_node.next before
# prev_node
prev_node.next = prev_node = node
elif t0 == _T_SOURCE:
f = self._expand_syms(self._expect_str_and_eol())
f = self._resolve(f, True)
for s in f:
self._enter_file(s)
prev_node = self._parse_block(None, # end_token
parent,
visible_if_deps,
prev_node)
self._leave_file()
elif t0 == end_token:
# We have reached the end of the block. Terminate the final
# node and return it.
prev_node.next = None
return prev_node
elif t0 == _T_IF:
node = MenuNode()
node.item = node.prompt = None
node.parent = parent
node.filename = self._filename
node.linenr = self._linenr
# See similar code in _parse_properties()
if isinstance(parent.item, Choice):
parent_dep = parent.item
else:
parent_dep = parent.dep
node.dep = self._make_and(parent_dep, self._parse_expr(True))
self._parse_block(_T_ENDIF,
node, # parent
visible_if_deps,
node) # prev_node
node.list = node.next
prev_node.next = prev_node = node
elif t0 == _T_MENU:
node = MenuNode()
node.kconfig = self
node.item = MENU
node.visibility = self.y
node.parent = parent
node.filename = self._filename
node.linenr = self._linenr
prompt = self._expect_str_and_eol()
self._parse_properties(node, visible_if_deps)
node.prompt = (prompt, node.dep)
self._parse_block(_T_ENDMENU,
node, # parent
self._make_and(visible_if_deps,
node.visibility),
node) # prev_node
node.list = node.next
prev_node.next = prev_node = node
elif t0 == _T_COMMENT:
node = MenuNode()
node.kconfig = self
node.item = COMMENT
node.list = None
node.parent = parent
node.filename = self._filename
node.linenr = self._linenr
prompt = self._expect_str_and_eol()
self._parse_properties(node, visible_if_deps)
node.prompt = (prompt, node.dep)
prev_node.next = prev_node = node
elif t0 == _T_CHOICE:
name = self._next_token()
if name is None:
choice = Choice()
self._choices.append(choice)
else:
# Named choice
choice = self.named_choices.get(name)
if not choice:
choice = Choice()
self._choices.append(choice)
choice.name = name
self.named_choices[name] = choice
choice.kconfig = self
node = MenuNode()
node.kconfig = self
node.item = choice
node.help = None
node.parent = parent
node.filename = self._filename
node.linenr = self._linenr
self._parse_properties(node, visible_if_deps)
self._parse_block(_T_ENDCHOICE,
node, # parent
visible_if_deps,
node) # prev_node
node.list = node.next
choice.nodes.append(node)
prev_node.next = prev_node = node
elif t0 == _T_MAINMENU:
self.top_node.prompt = (self._expect_str_and_eol(), self.y)
self.top_node.filename = self._filename
self.top_node.linenr = self._linenr
else:
self._parse_error("unrecognized construct")
# End of file reached. Terminate the final node and return it.
if end_token is not None:
raise KconfigSyntaxError("Unexpected end of file " +
self._filename)
prev_node.next = None
return prev_node
def _parse_cond(self):
"""
Parses an optional 'if <expr>' construct and returns the parsed <expr>,
or self.y if the next token is not _T_IF
"""
expr = self._parse_expr(True) if self._check_token(_T_IF) else self.y
if self._peek_token() is not None:
self._parse_error("extra tokens at end of line")
return expr
def _parse_properties(self, node, visible_if_deps):
"""
Parses properties for symbols, menus, choices, and comments. Also takes
care of propagating dependencies from the menu node to the properties
of the item (this mirrors the C tools, though they do it after
parsing).
node:
The menu node we're parsing properties on. Prompt, help text,
'depends on', and 'visible if' properties apply to the Menu node,
while the others apply to the contained item.
visible_if_deps:
'visible if' dependencies from enclosing menus. Propagated to Symbol
and Choice prompts.
"""
# New properties encountered at this location. A local 'depends on'
# only applies to these, in case a symbol is defined in multiple
# locations.
prompt = None
defaults = []
selects = []
implies = []
ranges = []
# Menu node dependencies from 'depends on'. Will get propagated to the
# properties above.
node.dep = self.y
while self._next_line():
t0 = self._next_token()
if t0 is None:
continue
if t0 in _TYPE_TOKENS:
new_type = _TOKEN_TO_TYPE[t0]
if node.item.orig_type != UNKNOWN and \
node.item.orig_type != new_type:
self._warn("{} defined with multiple types, {} will be used"
.format(_name_and_loc_str(node.item),
TYPE_TO_STR[new_type]))
node.item.orig_type = new_type
if self._peek_token() is not None:
if prompt:
self._warn("{} defined with multiple prompts in single location"
.format(_name_and_loc_str(node.item)))
prompt = (self._expect_str(), self._parse_cond())
elif t0 == _T_DEPENDS:
if not self._check_token(_T_ON):
self._parse_error('expected "on" after "depends"')
node.dep = self._make_and(node.dep, self._parse_expr(True))
elif t0 == _T_HELP:
# Find first non-blank (not all-space) line and get its
# indentation
if node.help is not None:
self._warn("{} defined with more than one help text -- "
"only the last one will be used"
.format(_name_and_loc_str(node.item)))
# Small optimization. This code is pretty hot.
readline = self._file.readline
while 1:
line = readline()
self._linenr += 1
if not line or not line.isspace():
break
if not line:
self._warn("{} has 'help' but empty help text"
.format(_name_and_loc_str(node.item)))
node.help = ""
break
indent = _indentation(line)
if indent == 0:
# If the first non-empty lines has zero indent, there is no
# help text
self._warn("{} has 'help' but empty help text"
.format(_name_and_loc_str(node.item)))
node.help = ""
self._saved_line = line # "Unget" the line
break
help_lines = [_dedent_rstrip(line, indent)]
# Small optimization
add_help_line = help_lines.append
# The help text goes on till the first non-empty line with less
# indent
while 1:
line = readline()
self._linenr += 1
if not (line and (line.isspace() or \
_indentation(line) >= indent)):
break
add_help_line(_dedent_rstrip(line, indent))
node.help = "\n".join(help_lines).rstrip() + "\n"
self._saved_line = line # "Unget" the line
elif t0 == _T_SELECT:
if not isinstance(node.item, Symbol):
self._parse_error("only symbols can select")
selects.append((self._expect_nonconst_sym(),
self._parse_cond()))
elif t0 == _T_IMPLY:
if not isinstance(node.item, Symbol):
self._parse_error("only symbols can imply")
implies.append((self._expect_nonconst_sym(),
self._parse_cond()))
elif t0 == _T_DEFAULT:
defaults.append((self._parse_expr(False), self._parse_cond()))
elif t0 in (_T_DEF_BOOL, _T_DEF_TRISTATE):
new_type = _TOKEN_TO_TYPE[t0]
if node.item.orig_type != UNKNOWN and \
node.item.orig_type != new_type:
self._warn("{} defined with multiple types, {} will be used"
.format(_name_and_loc_str(node.item),
TYPE_TO_STR[new_type]))
node.item.orig_type = new_type
defaults.append((self._parse_expr(False), self._parse_cond()))
elif t0 == _T_PROMPT:
# 'prompt' properties override each other within a single
# definition of a symbol, but additional prompts can be added
# by defining the symbol multiple times
if prompt:
self._warn("{} defined with multiple prompts in single location"
.format(_name_and_loc_str(node.item)))
prompt = (self._expect_str(), self._parse_cond())
elif t0 == _T_RANGE:
ranges.append((self._expect_sym(),
self._expect_sym(),
self._parse_cond()))
elif t0 == _T_OPTION:
if self._check_token(_T_ENV):
if not self._check_token(_T_EQUAL):
self._parse_error('expected "=" after "env"')
env_var = self._expect_str_and_eol()
node.item.env_var = env_var
if env_var not in os.environ:
self._warn("'option env=\"{0}\"' on symbol {1} has "
"no effect, because the environment "
"variable {0} is not set"
.format(env_var, node.item.name),
self._filename, self._linenr)
else:
defaults.append(
(self._lookup_const_sym(os.environ[env_var]),
self.y))
elif self._check_token(_T_DEFCONFIG_LIST):
if not self.defconfig_list:
self.defconfig_list = node.item
else:
self._warn("'option defconfig_list' set on multiple "
"symbols ({0} and {1}). Only {0} will be "
"used.".format(self.defconfig_list.name,
node.item.name),
self._filename, self._linenr)
elif self._check_token(_T_MODULES):
# To reduce warning spam, only warn if 'option modules' is
# set on some symbol that isn't MODULES, which should be
# safe. I haven't run into any projects that make use
# modules besides the kernel yet, and there it's likely to
# keep being called "MODULES".
if node.item is not self.modules:
self._warn("the 'modules' option is not supported. "
"Let me know if this is a problem for you, "
"as it wouldn't be that hard to implement. "
"Note that modules are supported -- "
"Kconfiglib just assumes the symbol name "
"MODULES, like older versions of the C "
"implementation did when 'option modules' "
"wasn't used.",
self._filename, self._linenr)
elif self._check_token(_T_ALLNOCONFIG_Y):
if not isinstance(node.item, Symbol):
self._parse_error("the 'allnoconfig_y' option is only "
"valid for symbols")
node.item.is_allnoconfig_y = True
else:
self._parse_error("unrecognized option")
elif t0 == _T_VISIBLE:
if not self._check_token(_T_IF):
self._parse_error('expected "if" after "visible"')
node.visibility = \
self._make_and(node.visibility, self._parse_expr(True))
elif t0 == _T_OPTIONAL:
if not isinstance(node.item, Choice):
self._parse_error('"optional" is only valid for choices')
node.item.is_optional = True
else:
self._tokens_i = -1
# Reuse the tokens for the non-property line later
self._has_tokens = True
break
# Done parsing properties. Now add the new
# prompts/defaults/selects/implies/ranges properties, with dependencies
# from node.dep propagated.
# First propagate parent dependencies to node.dep
# If the parent node holds a Choice, we use the Choice itself as the
# parent dependency. This matches the C implementation, and makes sense
# as the value (mode) of the choice limits the visibility of the
# contained choice symbols. Due to the similar interface, Choice works
# as a drop-in replacement for Symbol here.
if isinstance(node.parent.item, Choice):
node.dep = self._make_and(node.dep, node.parent.item)
else:
node.dep = self._make_and(node.dep, node.parent.dep)
if isinstance(node.item, (Symbol, Choice)):
if isinstance(node.item, Symbol):
# See the class documentation
node.item.direct_dep = \
self._make_or(node.item.direct_dep, node.dep)
# Set the prompt, with dependencies propagated
if prompt:
node.prompt = (prompt[0],
self._make_and(self._make_and(prompt[1],
node.dep),
visible_if_deps))
else:
node.prompt = None
# Add the new defaults, with dependencies propagated
for val_expr, cond in defaults:
node.item.defaults.append(
(val_expr, self._make_and(cond, node.dep)))
# Add the new ranges, with dependencies propagated
for low, high, cond in ranges:
node.item.ranges.append(
(low, high, self._make_and(cond, node.dep)))
# Handle selects
for target, cond in selects:
# Only stored for inspection. Not used during evaluation.
node.item.selects.append(
(target, self._make_and(cond, node.dep)))
# Modify the dependencies of the selected symbol
# Warning: See _warn_select_unsatisfied_deps()
target.rev_dep = \
self._make_or(target.rev_dep,
self._make_and(node.item,
self._make_and(cond,
node.dep)))
# Handle implies
for target, cond in implies:
# Only stored for inspection. Not used during evaluation.
node.item.implies.append(
(target, self._make_and(cond, node.dep)))
# Modify the dependencies of the implied symbol
target.weak_rev_dep = \
self._make_or(target.weak_rev_dep,
self._make_and(node.item,
self._make_and(cond,
node.dep)))
def _parse_expr(self, transform_m):
"""
Parses an expression from the tokens in Kconfig._tokens using a simple
top-down approach. See the module docs for the expression format.
transform_m:
True if m should be rewritten to m && MODULES. See the
Kconfig.eval_string() documentation.
"""
# Grammar:
#
# expr: and_expr ['||' expr]
# and_expr: factor ['&&' and_expr]
# factor: <symbol> ['='/'!='/'<'/... <symbol>]
# '!' factor
# '(' expr ')'
#
# It helps to think of the 'expr: and_expr' case as a single-operand OR
# (no ||), and of the 'and_expr: factor' case as a single-operand AND
# (no &&). Parsing code is always a bit tricky.
# Mind dump: parse_factor() and two nested loops for OR and AND would
# work as well. The straightforward implementation there gives a
# (op, (op, (op, A, B), C), D) parse for A op B op C op D. Representing
# expressions as (op, [list of operands]) instead goes nicely with that
# version, but is wasteful for short expressions and complicates
# expression evaluation and other code that works on expressions (more
# complicated code likely offsets any performance gain from less
# recursion too). If we also try to optimize the list representation by
# merging lists when possible (e.g. when ANDing two AND expressions),
# we end up allocating a ton of lists instead of reusing expressions,
# which is bad.
and_expr = self._parse_and_expr(transform_m)
# Return 'and_expr' directly if we have a "single-operand" OR.
# Otherwise, parse the expression on the right and make an OR node.
# This turns A || B || C || D into (OR, A, (OR, B, (OR, C, D))).
return and_expr \
if not self._check_token(_T_OR) else \
(OR, and_expr, self._parse_expr(transform_m))
def _parse_and_expr(self, transform_m):
factor = self._parse_factor(transform_m)
# Return 'factor' directly if we have a "single-operand" AND.
# Otherwise, parse the right operand and make an AND node. This turns
# A && B && C && D into (AND, A, (AND, B, (AND, C, D))).
return factor \
if not self._check_token(_T_AND) else \
(AND, factor, self._parse_and_expr(transform_m))
def _parse_factor(self, transform_m):
token = self._next_token()
if isinstance(token, Symbol):
# Plain symbol or relation
next_token = self._peek_token()
if next_token not in _TOKEN_TO_REL:
# Plain symbol
# For conditional expressions ('depends on <expr>',
# '... if <expr>', etc.), m is rewritten to m && MODULES.
if transform_m and token is self.m:
return (AND, self.m, self.modules)
return token
# Relation
return (_TOKEN_TO_REL[self._next_token()], token,
self._expect_sym())
if token == _T_NOT:
return (NOT, self._parse_factor(transform_m))
if token == _T_OPEN_PAREN:
expr_parse = self._parse_expr(transform_m)
if not self._check_token(_T_CLOSE_PAREN):
self._parse_error("missing end parenthesis")
return expr_parse
self._parse_error("malformed expression")
#
# Caching and invalidation
#
def _build_dep(self):
"""
Populates the Symbol/Choice._dependents sets, which contain all other
items (symbols and choices) that immediately depend on the item in the
sense that changing the value of the item might affect the value of the
dependent items. This is used for caching/invalidation.
The calculated sets might be larger than necessary as we don't do any
complex analysis of the expressions.
"""
# Only calculate _dependents for defined symbols. Constant and
# undefined symbols could theoretically be selected/implied, but it
# wouldn't change their value, so it's not a true dependency.
for sym in self.defined_syms:
# Symbols depend on the following:
# The prompt conditions
for node in sym.nodes:
if node.prompt:
_make_depend_on(sym, node.prompt[1])
# The default values and their conditions
for value, cond in sym.defaults:
_make_depend_on(sym, value)
_make_depend_on(sym, cond)
# The reverse and weak reverse dependencies
_make_depend_on(sym, sym.rev_dep)
_make_depend_on(sym, sym.weak_rev_dep)
# The ranges along with their conditions
for low, high, cond in sym.ranges:
_make_depend_on(sym, low)
_make_depend_on(sym, high)
_make_depend_on(sym, cond)
# The direct dependencies. This is usually redundant, as the direct
# dependencies get propagated to properties, but it's needed to get
# invalidation solid for 'imply', which only checks the direct
# dependencies (even if there are no properties to propagate it
# to).
_make_depend_on(sym, sym.direct_dep)
# In addition to the above, choice symbols depend on the choice
# they're in, but that's handled automatically since the Choice is
# propagated to the conditions of the properties before
# _build_dep() runs.
for choice in self._choices:
# Choices depend on the following:
# The prompt conditions
for node in choice.nodes:
if node.prompt:
_make_depend_on(choice, node.prompt[1])
# The default symbol conditions
for _, cond in choice.defaults:
_make_depend_on(choice, cond)
# The choice symbols themselves, because the y mode selection might
# change if a choice symbol's visibility changes
for sym in choice.syms:
sym._dependents.add(choice)
def _invalidate_all(self):
# Undefined symbols never change value and don't need to be
# invalidated, so we can just iterate over defined symbols.
# Invalidating constant symbols would break things horribly.
for sym in self.defined_syms:
sym._invalidate()
for choice in self._choices:
choice._invalidate()
#
# Misc.
#
def _expand_syms(self, s):
"""
Expands $-references to symbols in 's' to symbol values, or to the
empty string for undefined symbols.
"""
while 1:
sym_ref_match = _sym_ref_re_search(s)
if not sym_ref_match:
return s
sym = self.syms.get(sym_ref_match.group(1))
s = s[:sym_ref_match.start()] + \
(sym.str_value if sym else "") + \
s[sym_ref_match.end():]
def _parse_error(self, msg):
if self._filename is None:
loc = ""
else:
loc = "{}:{}: ".format(self._filename, self._linenr)
raise KconfigSyntaxError(
"{}Couldn't parse '{}': {}".format(loc, self._line.rstrip(), msg))
def _warn(self, msg, filename=None, linenr=None):
"""
For printing general warnings.
"""
if self._print_warnings:
_stderr_msg("warning: " + msg, filename, linenr)
def _warn_undef_assign(self, msg, filename=None, linenr=None):
"""
See the class documentation.
"""
if self._print_undef_assign:
_stderr_msg("warning: " + msg, filename, linenr)
def _warn_undef_assign_load(self, name, val, filename, linenr):
"""
Special version for load_config().
"""
self._warn_undef_assign(
'attempt to assign the value "{}" to the undefined symbol {}'
.format(val, name), filename, linenr)
def _warn_redun_assign(self, msg, filename=None, linenr=None):
"""
See the class documentation.
"""
if self._print_redun_assign:
_stderr_msg("warning: " + msg, filename, linenr)
class Symbol(object):
"""
Represents a configuration symbol:
(menu)config FOO
...
The following attributes are available. They should be viewed as read-only,
and some are implemented through @property magic (but are still efficient
to access due to internal caching).
Note: Prompts, help texts, and locations are stored in the Symbol's
MenuNode(s) rather than in the Symbol itself. Check the MenuNode class and
the Symbol.nodes attribute. This organization matches the C tools.
name:
The name of the symbol, e.g. "FOO" for 'config FOO'.
type:
The type of the symbol. One of BOOL, TRISTATE, STRING, INT, HEX, UNKNOWN.
UNKNOWN is for undefined symbols, (non-special) constant symbols, and
symbols defined without a type.
When running without modules (MODULES having the value n), TRISTATE
symbols magically change type to BOOL. This also happens for symbols
within choices in "y" mode. This matches the C tools, and makes sense for
menuconfig-like functionality.
orig_type:
The type as given in the Kconfig file, without any magic applied. Used
when printing the symbol.
str_value:
The value of the symbol as a string. Gives the value for string/int/hex
symbols. For bool/tristate symbols, gives "n", "m", or "y".
This is the symbol value that's used in relational expressions
(A = B, A != B, etc.)
Gotcha: For int/hex symbols, the exact format of the value must often be
preserved (e.g., when writing a .config file), hence why you can't get it
directly as an int. Do int(int_sym.str_value) or
int(hex_sym.str_value, 16) to get the integer value.
tri_value:
The tristate value of the symbol as an integer. One of 0, 1, 2,
representing n, m, y. Always 0 (n) for non-bool/tristate symbols.
This is the symbol value that's used outside of relation expressions
(A, !A, A && B, A || B).
assignable:
A tuple containing the tristate user values that can currently be
assigned to the symbol (that would be respected), ordered from lowest (0,
representing n) to highest (2, representing y). This corresponds to the
selections available in the menuconfig interface. The set of assignable
values is calculated from the symbol's visibility and selects/implies.
Returns the empty set for non-bool/tristate symbols and for symbols with
visibility n. The other possible values are (0, 2), (0, 1, 2), (1, 2),
(1,), and (2,). A (1,) or (2,) result means the symbol is visible but
"locked" to m or y through a select, perhaps in combination with the
visibility. menuconfig represents this as -M- and -*-, respectively.
For string/hex/int symbols, check if Symbol.visibility is non-0 (non-n)
instead to determine if the value can be changed.
Some handy 'assignable' idioms:
# Is 'sym' an assignable (visible) bool/tristate symbol?
if sym.assignable:
# What's the highest value it can be assigned? [-1] in Python
# gives the last element.
sym_high = sym.assignable[-1]
# The lowest?
sym_low = sym.assignable[0]
# Can the symbol be set to at least m?
if sym.assignable[-1] >= 1:
...
# Can the symbol be set to m?
if 1 in sym.assignable:
...
visibility:
The visibility of the symbol. One of 0, 1, 2, representing n, m, y. See
the module documentation for an overview of symbol values and visibility.
user_value:
The user value of the symbol. None if no user value has been assigned
(via Kconfig.load_config() or Symbol.set_value()).
Holds 0, 1, or 2 for bool/tristate symbols, and a string for the other
symbol types.
WARNING: Do not assign directly to this. It will break things. Use
Symbol.set_value().
config_string:
The .config assignment string that would get written out for the symbol
by Kconfig.write_config(). None if no .config assignment would get
written out. In general, visible symbols, symbols with (active) defaults,
and selected symbols get written out.
nodes:
A list of MenuNodes for this symbol. Will contain a single MenuNode for
most symbols. Undefined and constant symbols have an empty nodes list.
Symbols defined in multiple locations get one node for each location.
choice:
Holds the parent Choice for choice symbols, and None for non-choice
symbols. Doubles as a flag for whether a symbol is a choice symbol.
defaults:
List of (default, cond) tuples for the symbol's 'default' properties. For
example, 'default A && B if C || D' is represented as
((AND, A, B), (OR, C, D)). If no condition was given, 'cond' is
self.kconfig.y.
Note that 'depends on' and parent dependencies are propagated to
'default' conditions.
selects:
List of (symbol, cond) tuples for the symbol's 'select' properties. For
example, 'select A if B && C' is represented as (A, (AND, B, C)). If no
condition was given, 'cond' is self.kconfig.y.
Note that 'depends on' and parent dependencies are propagated to 'select'
conditions.
implies:
Like 'selects', for imply.
ranges:
List of (low, high, cond) tuples for the symbol's 'range' properties. For
example, 'range 1 2 if A' is represented as (1, 2, A). If there is no
condition, 'cond' is self.config.y.
Note that 'depends on' and parent dependencies are propagated to 'range'
conditions.
Gotcha: 1 and 2 above will be represented as (undefined) Symbols rather
than plain integers. Undefined symbols get their name as their string
value, so this works out. The C tools work the same way.
rev_dep:
Reverse dependency expression from other symbols selecting this symbol.
Multiple selections get ORed together. A condition on a select is ANDed
with the selecting symbol.
For example, if A has 'select FOO' and B has 'select FOO if C', then
FOO's rev_dep will be (OR, A, (AND, B, C)).
weak_rev_dep:
Like rev_dep, for imply.
direct_dep:
The 'depends on' dependencies. If a symbol is defined in multiple
locations, the dependencies at each location are ORed together.
Internally, this is used to implement 'imply', which only applies if the
implied symbol has expr_value(self.direct_dep) != 0. 'depends on' and
parent dependencies are automatically propagated to the conditions of
properties, so normally it's redundant to check the direct dependencies.
env_var:
If the Symbol has an 'option env="FOO"' option, this contains the name
("FOO") of the environment variable. None for symbols that aren't set
from the environment.
'option env="FOO"' acts as a 'default' property whose value is the value
of $FOO.
env_var is set to "<uname release>" for the predefined symbol
UNAME_RELEASE, which holds the 'release' field from uname.
Symbols with an 'option env' option are never written out to .config
files, even if they are visible. env_var corresponds to a flag called
SYMBOL_AUTO in the C implementation.
is_allnoconfig_y:
True if the symbol has 'option allnoconfig_y' set on it. This has no
effect internally (except when printing symbols), but can be checked by
scripts.
is_constant:
True if the symbol is a constant (quoted) symbol.
kconfig:
The Kconfig instance this symbol is from.
"""
__slots__ = (
"_cached_assignable",
"_cached_str_val",
"_cached_tri_val",
"_cached_vis",
"_dependents",
"_was_set",
"_write_to_conf",
"_written",
"choice",
"defaults",
"direct_dep",
"env_var",
"implies",
"is_allnoconfig_y",
"is_constant",
"kconfig",
"name",
"nodes",
"orig_type",
"ranges",
"rev_dep",
"selects",
"user_value",
"weak_rev_dep",
)
#
# Public interface
#
@property
def type(self):
"""
See the class documentation.
"""
if self.orig_type == TRISTATE and \
((self.choice and self.choice.tri_value == 2) or
not self.kconfig.modules.tri_value):
return BOOL
return self.orig_type
@property
def str_value(self):
"""
See the class documentation.
"""
if self._cached_str_val is not None:
return self._cached_str_val
if self.orig_type in (BOOL, TRISTATE):
# Also calculates the visibility, so invalidation safe
self._cached_str_val = TRI_TO_STR[self.tri_value]
return self._cached_str_val
# As a quirk of Kconfig, undefined symbols get their name as their
# string value. This is why things like "FOO = bar" work for seeing if
# FOO has the value "bar".
if self.orig_type == UNKNOWN:
self._cached_str_val = self.name
return self.name
val = ""
# Warning: See Symbol._rec_invalidate(), and note that this is a hidden
# function call (property magic)
vis = self.visibility
self._write_to_conf = (vis != 0)
if self.orig_type in (INT, HEX):
# The C implementation checks the user value against the range in a
# separate code path (post-processing after loading a .config).
# Checking all values here instead makes more sense for us. It
# requires that we check for a range first.
base = _TYPE_TO_BASE[self.orig_type]
# Check if a range is in effect
for low_expr, high_expr, cond in self.ranges:
if expr_value(cond):
has_active_range = True
# The zeros are from the C implementation running strtoll()
# on empty strings
low = int(low_expr.str_value, base) if \
_is_base_n(low_expr.str_value, base) else 0
high = int(high_expr.str_value, base) if \
_is_base_n(high_expr.str_value, base) else 0
break
else:
has_active_range = False
if vis and self.user_value is not None and \
_is_base_n(self.user_value, base) and \
(not has_active_range or
low <= int(self.user_value, base) <= high):
# If the user value is well-formed and satisfies range
# contraints, it is stored in exactly the same form as
# specified in the assignment (with or without "0x", etc.)
val = self.user_value
else:
# No user value or invalid user value. Look at defaults.
found = False
for val_expr, cond in self.defaults:
if expr_value(cond):
self._write_to_conf = True
val = val_expr.str_value
if _is_base_n(val, base):
val_num = int(val, base)
else:
val_num = 0 # strtoll() on empty string
found = True
#break
if not found:
val_num = 0 # strtoll() on empty string
# This clamping procedure runs even if there's no default
if has_active_range:
clamp = None
if val_num < low:
clamp = low
elif val_num > high:
clamp = high
if clamp is not None:
# The value is rewritten to a standard form if it is
# clamped
val = str(clamp) \
if self.orig_type == INT else \
hex(clamp)
elif self.orig_type == STRING:
if vis and self.user_value is not None:
# If the symbol is visible and has a user value, use that
val = self.user_value
else:
# Otherwise, look at defaults
for val_expr, cond in self.defaults:
if expr_value(cond):
val = val_expr.str_value
self._write_to_conf = True
#break
# Corresponds to SYMBOL_AUTO in the C implementation
if self.env_var is not None:
self._write_to_conf = False
self._cached_str_val = val
return val
@property
def tri_value(self):
"""
See the class documentation.
"""
if self._cached_tri_val is not None:
return self._cached_tri_val
if self.orig_type not in (BOOL, TRISTATE):
self._cached_tri_val = 0
return 0
val = 0
# Warning: See Symbol._rec_invalidate(), and note that this is a hidden
# function call (property magic)
vis = self.visibility
self._write_to_conf = (vis != 0)
if not self.choice:
# Non-choice symbol
if vis and self.user_value is not None:
# If the symbol is visible and has a user value, use that
val = min(self.user_value, vis)
else:
# Otherwise, look at defaults and weak reverse dependencies
# (implies)
for default, cond in self.defaults:
cond_val = expr_value(cond)
if cond_val:
val = min(expr_value(default), cond_val)
self._write_to_conf = True
#break
# Weak reverse dependencies are only considered if our
# direct dependencies are met
weak_rev_dep_val = expr_value(self.weak_rev_dep)
if weak_rev_dep_val and expr_value(self.direct_dep):
val = max(weak_rev_dep_val, val)
self._write_to_conf = True
# Reverse (select-related) dependencies take precedence
rev_dep_val = expr_value(self.rev_dep)
if rev_dep_val:
val = max(rev_dep_val, val)
self._write_to_conf = True
if not expr_value(self.direct_dep):
self._warn_select_unsatisfied_deps()
# m is promoted to y for (1) bool symbols and (2) symbols with a
# weak_rev_dep (from imply) of y
if val == 1 and \
(self.type == BOOL or expr_value(self.weak_rev_dep) == 2):
val = 2
elif vis == 2:
# Visible choice symbol in y-mode choice. The choice mode limits
# the visibility of choice symbols, so it's sufficient to just
# check the visibility of the choice symbols themselves.
val = 2 if self.choice.selection is self else 0
elif vis and self.user_value:
# Visible choice symbol in m-mode choice, with set non-0 user value
val = 1
self._cached_tri_val = val
return val
@property
def assignable(self):
"""
See the class documentation.
"""
if self._cached_assignable is None:
self._cached_assignable = self._get_assignable()
return self._cached_assignable
@property
def visibility(self):
"""
See the class documentation.
"""
if self._cached_vis is None:
self._cached_vis = _get_visibility(self)
return self._cached_vis
@property
def config_string(self):
"""
See the class documentation.
"""
# Note: _write_to_conf is determined when the value is calculated. This
# is a hidden function call due to property magic.
val = self.str_value
if not self._write_to_conf:
return None
if self.orig_type in (BOOL, TRISTATE):
return "{}{}={}\n" \
.format(self.kconfig.config_prefix, self.name, val) \
if val != "n" else \
"# {}{} is not set\n" \
.format(self.kconfig.config_prefix, self.name)
if self.orig_type in (INT, HEX):
return "{}{}={}\n" \
.format(self.kconfig.config_prefix, self.name, val)
if self.orig_type == STRING:
return '{}{}="{}"\n' \
.format(self.kconfig.config_prefix, self.name, escape(val))
_internal_error("Internal error while creating .config: unknown "
'type "{}".'.format(self.orig_type))
def set_value(self, value):
"""
Sets the user value of the symbol.
Equal in effect to assigning the value to the symbol within a .config
file. For bool and tristate symbols, use the 'assignable' attribute to
check which values can currently be assigned. Setting values outside
'assignable' will cause Symbol.user_value to differ from
Symbol.str/tri_value (be truncated down or up).
Setting a choice symbol to 2 (y) only updates Choice.user_selection on
the parent choice and not Symbol.user_value itself. This gives the
expected behavior when a choice is switched between different modes.
Choice.user_selection is considered when the choice is in y mode (the
"normal" mode).
Other symbols that depend (possibly indirectly) on this symbol are
automatically recalculated to reflect the assigned value.
value:
The user value to give to the symbol. For bool and tristate symbols,
n/m/y can be specified either as 0/1/2 (the usual format for tristate
values in Kconfiglib) or as one of the strings "n"/"m"/"y". For other
symbol types, pass a string.
Values that are invalid for the type (such as "foo" or 1 (m) for a
BOOL or "0x123" for an INT) are ignored and won't be stored in
Symbol.user_value. Kconfiglib will print a warning by default for
invalid assignments, and set_value() will return False.
Returns True if the value is valid for the type of the symbol, and
False otherwise. This only looks at the form of the value. For BOOL and
TRISTATE symbols, check the Symbol.assignable attribute to see what
values are currently in range and would actually be reflected in the
value of the symbol. For other symbol types, check whether the
visibility is non-n.
"""
if value == self.user_value:
# We know the value must be valid if it was successfully set
# previously
self._was_set = True
return True
# Check if the value is valid for our type
if not ((self.orig_type == BOOL and value in (0, 2, "n", "y") ) or
(self.orig_type == TRISTATE and value in (0, 1, 2, "n", "m", "y")) or
(self.orig_type == STRING and isinstance(value, str) ) or
(self.orig_type == INT and isinstance(value, str)
and _is_base_n(value, 10) ) or
(self.orig_type == HEX and isinstance(value, str)
and _is_base_n(value, 16)
and int(value, 16) >= 0)):
# Display tristate values as n, m, y in the warning
self.kconfig._warn(
"the value {} is invalid for {}, which has type {} -- "
"assignment ignored"
.format(TRI_TO_STR[value] if value in (0, 1, 2) else
"'{}'".format(value),
_name_and_loc_str(self),
TYPE_TO_STR[self.orig_type]))
return False
if self.env_var is not None:
self.kconfig._warn("ignored attempt to assign user value to "
"{}, which gets its value from the environment"
.format(_name_and_loc_str(self)))
return False
if self.orig_type in (BOOL, TRISTATE) and value in ("n", "m", "y"):
value = STR_TO_TRI[value]
if self.choice and value == 2:
# Remember this as a choice selection only. Makes switching back
# and forth between choice modes work as expected, and makes the
# check for whether the user value is the same as before above
# safe.
self.choice.user_selection = self
self.choice._was_set = True
self.choice._rec_invalidate()
else:
self.user_value = value
self._was_set = True
self._rec_invalidate_if_has_prompt()
return True
def unset_value(self):
"""
Resets the user value of the symbol, as if the symbol had never gotten
a user value via Kconfig.load_config() or Symbol.set_value().
"""
if self.user_value is not None:
self.user_value = None
self._rec_invalidate_if_has_prompt()
def __repr__(self):
"""
Returns a string with information about the symbol (including its name,
value, visibility, and location(s)) when it is evaluated on e.g. the
interactive Python prompt.
"""
fields = []
fields.append("symbol " + self.name)
fields.append(TYPE_TO_STR[self.type])
for node in self.nodes:
if node.prompt:
fields.append('"{}"'.format(node.prompt[0]))
# Only add quotes for non-bool/tristate symbols
fields.append("value " +
(self.str_value
if self.orig_type in (BOOL, TRISTATE) else
'"{}"'.format(self.str_value)))
if not self.is_constant:
# These aren't helpful to show for constant symbols
if self.user_value is not None:
# Only add quotes for non-bool/tristate symbols
fields.append("user value " +
(TRI_TO_STR[self.user_value]
if self.orig_type in (BOOL, TRISTATE) else
'"{}"'.format(self.user_value)))
fields.append("visibility " + TRI_TO_STR[self.visibility])
if self.choice:
fields.append("choice symbol")
if self.is_allnoconfig_y:
fields.append("allnoconfig_y")
if self is self.kconfig.defconfig_list:
fields.append("is the defconfig_list symbol")
if self.env_var is not None:
fields.append("from environment variable " + self.env_var)
if self is self.kconfig.modules:
fields.append("is the modules symbol")
fields.append("direct deps " +
TRI_TO_STR[expr_value(self.direct_dep)])
if self.nodes:
for node in self.nodes:
fields.append("{}:{}".format(node.filename, node.linenr))
else:
if self.is_constant:
fields.append("constant")
else:
fields.append("undefined")
return "<{}>".format(", ".join(fields))
def __str__(self):
"""
Returns a string representation of the symbol when it is printed,
matching the Kconfig format. Prompts and help texts are included,
though they really belong to the symbol's menu nodes rather than the
symbol itself.
The output is designed so that feeding it back to a Kconfig parser
redefines the symbol as is. This also works for symbols defined in
multiple locations, where all the definitions are output. See the
module documentation for a small gotcha related to choice symbols.
An empty string is returned for undefined and constant symbols.
"""
return _sym_choice_str(self)
#
# Private methods
#
def __init__(self):
"""
Symbol constructor -- not intended to be called directly by Kconfiglib
clients.
"""
# These attributes are always set on the instance from outside and
# don't need defaults:
# _written
# kconfig
# direct_dep
# is_constant
# name
# rev_dep
# weak_rev_dep
self.orig_type = UNKNOWN
self.defaults = []
self.selects = []
self.implies = []
self.ranges = []
self.nodes = []
self.user_value = \
self.choice = \
self.env_var = \
self._cached_str_val = self._cached_tri_val = self._cached_vis = \
self._cached_assignable = None
# _write_to_conf is calculated along with the value. If True, the
# Symbol gets a .config entry.
self.is_allnoconfig_y = \
self._was_set = \
self._write_to_conf = False
# See Kconfig._build_dep()
self._dependents = set()
def _get_assignable(self):
"""
Worker function for the 'assignable' attribute.
"""
if self.orig_type not in (BOOL, TRISTATE):
return ()
# Warning: See Symbol._rec_invalidate(), and note that this is a hidden
# function call (property magic)
vis = self.visibility
if not vis:
return ()
rev_dep_val = expr_value(self.rev_dep)
if vis == 2:
if self.choice:
return (2,)
if not rev_dep_val:
if self.type == BOOL or expr_value(self.weak_rev_dep) == 2:
return (0, 2)
return (0, 1, 2)
if rev_dep_val == 2:
return (2,)
# rev_dep_val == 1
if self.type == BOOL or expr_value(self.weak_rev_dep) == 2:
return (2,)
return (1, 2)
# vis == 1
# Must be a tristate here, because bool m visibility gets promoted to y
if not rev_dep_val:
return (0, 1) if expr_value(self.weak_rev_dep) != 2 else (0, 2)
if rev_dep_val == 2:
return (2,)
# vis == rev_dep_val == 1
return (1,)
def _invalidate(self):
"""
Marks the symbol as needing to be recalculated.
"""
self._cached_str_val = self._cached_tri_val = self._cached_vis = \
self._cached_assignable = None
def _rec_invalidate(self):
"""
Invalidates the symbol and all items that (possibly) depend on it.
"""
if self is self.kconfig.modules:
# Invalidating MODULES has wide-ranging effects
self.kconfig._invalidate_all()
else:
self._invalidate()
for item in self._dependents:
# _cached_vis doubles as a flag that tells us whether 'item'
# has cached values, because it's calculated as a side effect
# of calculating all other (non-constant) cached values.
#
# If item._cached_vis is None, it means there can't be cached
# values on other items that depend on 'item', because if there
# were, some value on 'item' would have been calculated and
# item._cached_vis set as a side effect. It's therefore safe to
# stop the invalidation at symbols with _cached_vis None.
#
# This approach massively speeds up scripts that set a lot of
# values, vs simply invalidating all possibly dependent symbols
# (even when you already have a list of all the dependent
# symbols, because some symbols get huge dependency trees).
#
# This gracefully handles dependency loops too, which is nice
# for choices, where the choice depends on the choice symbols
# and vice versa.
if item._cached_vis is not None:
item._rec_invalidate()
def _rec_invalidate_if_has_prompt(self):
"""
Invalidates the symbol and its dependent symbols, but only if the
symbol has a prompt. User values never have an effect on promptless
symbols, so we skip invalidation for them as an optimization.
This also prevents constant (quoted) symbols from being invalidated if
set_value() is called on them, which would cause them to lose their
value and break things.
Prints a warning if the symbol has no prompt. In some contexts (e.g.
when loading a .config files) assignments to promptless symbols are
normal and expected, so the warning can be disabled.
"""
for node in self.nodes:
if node.prompt:
self._rec_invalidate()
return
if self.kconfig._warn_no_prompt:
self.kconfig._warn(_name_and_loc_str(self) + " has no prompt, "
"meaning user values have no effect on it")
def _warn_select_unsatisfied_deps(self):
"""
Helper for printing an informative warning when a symbol with
unsatisfied direct dependencies (dependencies from 'depends on', ifs,
and menus) is selected by some other symbol
"""
warn_msg = "{} has unsatisfied direct dependencies ({}), but is " \
"currently being selected by the following symbols:" \
.format(_name_and_loc_str(self),
expr_str(self.direct_dep))
# Returns a warning string if 'select' is actually selecting us, and
# the empty string otherwise
def check_select(select):
# No 'nonlocal' in Python 2. Just return the string to append to
# warn_msg instead.
select_val = expr_value(select)
if not select_val:
# Only include selects that are not n
return ""
if isinstance(select, tuple):
# (AND, <sym>, <condition>)
selecting_sym = select[1]
else:
# <sym>
selecting_sym = select
msg = "\n{}, with value {}, direct dependencies {} " \
"(value: {})" \
.format(_name_and_loc_str(selecting_sym),
selecting_sym.str_value,
expr_str(selecting_sym.direct_dep),
TRI_TO_STR[expr_value(selecting_sym.direct_dep)])
if isinstance(select, tuple):
msg += ", and select condition {} (value: {})" \
.format(expr_str(select[2]),
TRI_TO_STR[expr_value(select[2])])
return msg
expr = self.rev_dep
while 1:
# This relies on us using the following format for the select
# expression (which is nice in that it preserves the order of the
# selecting symbols):
#
# (OR, (OR, (OR, <expr 1>, <expr 2>), <expr 3>), <expr 4>)
#
# We could do fancier expression processing later if needed.
if isinstance(expr, tuple) and expr[0] == OR:
warn_msg += check_select(expr[2])
# Go to the next select
expr = expr[1]
else:
warn_msg += check_select(expr)
break
self.kconfig._warn(warn_msg)
class Choice(object):
"""
Represents a choice statement:
choice
...
endchoice
The following attributes are available on Choice instances. They should be
treated as read-only, and some are implemented through @property magic (but
are still efficient to access due to internal caching).
Note: Prompts, help texts, and locations are stored in the Choice's
MenuNode(s) rather than in the Choice itself. Check the MenuNode class and
the Choice.nodes attribute. This organization matches the C tools.
name:
The name of the choice, e.g. "FOO" for 'choice FOO', or None if the
Choice has no name. I can't remember ever seeing named choices in
practice, but the C tools support them too.
type:
The type of the choice. One of BOOL, TRISTATE, UNKNOWN. UNKNOWN is for
choices defined without a type where none of the contained symbols have a
type either (otherwise the choice inherits the type of the first symbol
defined with a type).
When running without modules (CONFIG_MODULES=n), TRISTATE choices
magically change type to BOOL. This matches the C tools, and makes sense
for menuconfig-like functionality.
orig_type:
The type as given in the Kconfig file, without any magic applied. Used
when printing the choice.
tri_value:
The tristate value (mode) of the choice. A choice can be in one of three
modes:
0 (n) - The choice is disabled and no symbols can be selected. For
visible choices, this mode is only possible for choices with
the 'optional' flag set (see kconfig-language.txt).
1 (m) - Any number of choice symbols can be set to m, the rest will
be n.
2 (y) - One symbol will be y, the rest n.
Only tristate choices can be in m mode. The visibility of the choice is
an upper bound on the mode, and the mode in turn is an upper bound on the
visibility of the choice symbols.
To change the mode, use Choice.set_value().
Implementation note:
The C tools internally represent choices as a type of symbol, with
special-casing in many code paths. This is why there is a lot of
similarity to Symbol. The value (mode) of a choice is really just a
normal symbol value, and an implicit reverse dependency forces its
lower bound to m for visible non-optional choices (the reverse
dependency is 'm && <visibility>').
Symbols within choices get the choice propagated as a dependency to
their properties. This turns the mode of the choice into an upper bound
on e.g. the visibility of choice symbols, and explains the gotcha
related to printing choice symbols mentioned in the module docstring.
Kconfiglib uses a separate Choice class only because it makes the code
and interface less confusing (especially in a user-facing interface).
Corresponding attributes have the same name in the Symbol and Choice
classes, for consistency and compatibility.
assignable:
See the symbol class documentation. Gives the assignable values (modes).
visibility:
See the Symbol class documentation. Acts on the value (mode).
selection:
The Symbol instance of the currently selected symbol. None if the Choice
is not in y mode or has no selected symbol (due to unsatisfied
dependencies on choice symbols).
WARNING: Do not assign directly to this. It will break things. Call
sym.set_value(2) on the choice symbol you want to select instead.
user_value:
The value (mode) selected by the user through Choice.set_value(). Either
0, 1, or 2, or None if the user hasn't selected a mode. See
Symbol.user_value.
WARNING: Do not assign directly to this. It will break things. Use
Choice.set_value() instead.
user_selection:
The symbol selected by the user (by setting it to y). Ignored if the
choice is not in y mode, but still remembered so that the choice "snaps
back" to the user selection if the mode is changed back to y. This might
differ from 'selection' due to unsatisfied dependencies.
WARNING: Do not assign directly to this. It will break things. Call
sym.set_value(2) on the choice symbol to be selected instead.
syms:
List of symbols contained in the choice.
Gotcha: If a symbol depends on the previous symbol within a choice so
that an implicit menu is created, it won't be a choice symbol, and won't
be included in 'syms'. There are real-world examples of this, and it was
a PITA to support in older versions of Kconfiglib that didn't implement
the menu structure.
nodes:
A list of MenuNodes for this choice. In practice, the list will probably
always contain a single MenuNode, but it is possible to give a choice a
name and define it in multiple locations (I've never even seen a named
choice though).
defaults:
List of (symbol, cond) tuples for the choice's 'defaults' properties. For
example, 'default A if B && C' is represented as (A, (AND, B, C)). If
there is no condition, 'cond' is self.config.y.
Note that 'depends on' and parent dependencies are propagated to
'default' conditions.
is_optional:
True if the choice has the 'optional' flag set on it and can be in
n mode.
kconfig:
The Kconfig instance this choice is from.
"""
__slots__ = (
"_cached_assignable",
"_cached_selection",
"_cached_vis",
"_dependents",
"_was_set",
"defaults",
"is_constant",
"is_optional",
"kconfig",
"name",
"nodes",
"orig_type",
"syms",
"user_selection",
"user_value",
)
#
# Public interface
#
@property
def type(self):
"""
Returns the type of the choice. See Symbol.type.
"""
if self.orig_type == TRISTATE and not self.kconfig.modules.tri_value:
return BOOL
return self.orig_type
@property
def str_value(self):
"""
See the class documentation.
"""
return TRI_TO_STR[self.tri_value]
@property
def tri_value(self):
"""
See the class documentation.
"""
# This emulates a reverse dependency of 'm && visibility' for
# non-optional choices, which is how the C implementation does it
val = 0 if self.is_optional else 1
if self.user_value is not None:
val = max(val, self.user_value)
# Warning: See Symbol._rec_invalidate(), and note that this is a hidden
# function call (property magic)
val = min(val, self.visibility)
# Promote m to y for boolean choices
return 2 if val == 1 and self.type == BOOL else val
@property
def assignable(self):
"""
See the class documentation.
"""
if self._cached_assignable is None:
self._cached_assignable = self._get_assignable()
return self._cached_assignable
@property
def visibility(self):
"""
See the class documentation.
"""
if self._cached_vis is None:
self._cached_vis = _get_visibility(self)
return self._cached_vis
@property
def selection(self):
"""
See the class documentation.
"""
if self._cached_selection is _NO_CACHED_SELECTION:
self._cached_selection = self._get_selection()
return self._cached_selection
def set_value(self, value):
"""
Sets the user value (mode) of the choice. Like for Symbol.set_value(),
the visibility might truncate the value. Choices without the 'optional'
attribute (is_optional) can never be in n mode, but 0/"n" is still
accepted since it's not a malformed value (though it will have no
effect).
Returns True if the value is valid for the type of the choice, and
False otherwise. This only looks at the form of the value. Check the
Choice.assignable attribute to see what values are currently in range
and would actually be reflected in the mode of the choice.
"""
if value == self.user_value:
# We know the value must be valid if it was successfully set
# previously
self._was_set = True
return True
if not ((self.orig_type == BOOL and value in (0, 2, "n", "y") ) or
(self.orig_type == TRISTATE and value in (0, 1, 2, "n", "m", "y"))):
# Display tristate values as n, m, y in the warning
self.kconfig._warn(
"the value {} is invalid for {}, which has type {} -- "
"assignment ignored"
.format(TRI_TO_STR[value] if value in (0, 1, 2) else
"'{}'".format(value),
_name_and_loc_str(self),
TYPE_TO_STR[self.orig_type]))
return False
if value in ("n", "m", "y"):
value = STR_TO_TRI[value]
self.user_value = value
self._was_set = True
self._rec_invalidate()
return True
def unset_value(self):
"""
Resets the user value (mode) and user selection of the Choice, as if
the user had never touched the mode or any of the choice symbols.
"""
if self.user_value is not None or self.user_selection:
self.user_value = self.user_selection = None
self._rec_invalidate()
def __repr__(self):
"""
Returns a string with information about the choice when it is evaluated
on e.g. the interactive Python prompt.
"""
fields = []
fields.append("choice" if self.name is None else \
"choice " + self.name)
fields.append(TYPE_TO_STR[self.type])
for node in self.nodes:
if node.prompt:
fields.append('"{}"'.format(node.prompt[0]))
fields.append("mode " + self.str_value)
if self.user_value is not None:
fields.append('user mode {}'.format(TRI_TO_STR[self.user_value]))
if self.selection:
fields.append("{} selected".format(self.selection.name))
if self.user_selection:
user_sel_str = "{} selected by user" \
.format(self.user_selection.name)
if self.selection is not self.user_selection:
user_sel_str += " (overridden)"
fields.append(user_sel_str)
fields.append("visibility " + TRI_TO_STR[self.visibility])
if self.is_optional:
fields.append("optional")
for node in self.nodes:
fields.append("{}:{}".format(node.filename, node.linenr))
return "<{}>".format(", ".join(fields))
def __str__(self):
"""
Returns a string representation of the choice when it is printed,
matching the Kconfig format (though without the contained choice
symbols). Prompts and help texts are included, though they really
belong to the choice's menu nodes rather than the choice itself.
See Symbol.__str__() as well.
"""
return _sym_choice_str(self)
#
# Private methods
#
def __init__(self):
"""
Choice constructor -- not intended to be called directly by Kconfiglib
clients.
"""
# These attributes are always set on the instance from outside and
# don't need defaults:
# kconfig
self.orig_type = UNKNOWN
self.syms = []
self.defaults = []
self.nodes = []
self.name = \
self.user_value = self.user_selection = \
self._cached_vis = self._cached_assignable = None
self._cached_selection = _NO_CACHED_SELECTION
# is_constant is checked by _make_depend_on(). Just set it to avoid
# having to special-case choices.
self.is_constant = self.is_optional = False
# See Kconfig._build_dep()
self._dependents = set()
def _get_assignable(self):
"""
Worker function for the 'assignable' attribute.
"""
# Warning: See Symbol._rec_invalidate(), and note that this is a hidden
# function call (property magic)
vis = self.visibility
if not vis:
return ()
if vis == 2:
if not self.is_optional:
return (2,) if self.type == BOOL else (1, 2)
return (0, 2) if self.type == BOOL else (0, 1, 2)
# vis == 1
return (0, 1) if self.is_optional else (1,)
def _get_selection(self):
"""
Worker function for the 'selection' attribute.
"""
# Warning: See Symbol._rec_invalidate(), and note that this is a hidden
# function call (property magic)
if self.tri_value != 2:
return None
# Use the user selection if it's visible
if self.user_selection and self.user_selection.visibility == 2:
return self.user_selection
# Otherwise, check if we have a default
for sym, cond in self.defaults:
# The default symbol must be visible too
if expr_value(cond) and sym.visibility:
return sym
# Otherwise, pick the first visible symbol, if any
for sym in self.syms:
if sym.visibility:
return sym
# Couldn't find a selection
return None
def _invalidate(self):
self._cached_vis = self._cached_assignable = None
self._cached_selection = _NO_CACHED_SELECTION
def _rec_invalidate(self):
"""
See Symbol._rec_invalidate()
"""
self._invalidate()
for item in self._dependents:
if item._cached_vis is not None:
item._rec_invalidate()
class MenuNode(object):
"""
Represents a menu node in the configuration. This corresponds to an entry
in e.g. the 'make menuconfig' interface, though non-visible choices, menus,
and comments also get menu nodes. If a symbol or choice is defined in
multiple locations, it gets one menu node for each location.
The top-level menu node, corresponding to the implicit top-level menu, is
available in Kconfig.top_node.
The menu nodes for a Symbol or Choice can be found in the
Symbol/Choice.nodes attribute. Menus and comments are represented as plain
menu nodes, with their text stored in the prompt attribute (prompt[0]).
This mirrors the C implementation.
The following attributes are available on MenuNode instances. They should
be viewed as read-only.
item:
Either a Symbol, a Choice, or one of the constants MENU and COMMENT.
Menus and comments are represented as plain menu nodes. Ifs are collapsed
(matching the C implementation) and do not appear in the final menu tree.
next:
The following menu node. None if there is no following node.
list:
The first child menu node. None if there are no children.
Choices and menus naturally have children, but Symbols can also have
children because of menus created automatically from dependencies (see
kconfig-language.txt).
parent:
The parent menu node. None if there is no parent.
prompt:
A (string, cond) tuple with the prompt for the menu node and its
conditional expression (which is self.kconfig.y if there is no
condition). None if there is no prompt.
For symbols and choices, the prompt is stored in the MenuNode rather than
the Symbol or Choice instance. For menus and comments, the prompt holds
the text.
help:
The help text for the menu node for Symbols and Choices. None if there is
no help text. Always stored in the node rather than the Symbol or Choice.
It is possible to have a separate help text at each location if a symbol
is defined in multiple locations.
dep:
The 'depends on' dependencies for the menu node, or self.kconfig.y if
there are no dependencies. Parent dependencies are propagated to this
attribute, and this attribute is then in turn propagated to the
properties of symbols and choices.
If a symbol is defined in multiple locations, only the properties defined
at a particular location get the corresponding MenuNode.dep dependencies
propagated to them.
visibility:
The 'visible if' dependencies for the menu node (which must represent a
menu), or self.kconfig.y if there are no 'visible if' dependencies.
'visible if' dependencies are recursively propagated to the prompts of
symbols and choices within the menu.
is_menuconfig:
True if the symbol for the menu node (it must be a symbol) was defined
with 'menuconfig' rather than 'config' (at this location). This is a hint
on how to display the menu entry (display the children in a separate menu
rather than indenting them). It's ignored internally by Kconfiglib,
except when printing symbols.
filename/linenr:
The location where the menu node appears.
kconfig:
The Kconfig instance the menu node is from.
"""
__slots__ = (
"dep",
"filename",
"help",
"is_menuconfig",
"item",
"kconfig",
"linenr",
"list",
"next",
"parent",
"prompt",
"visibility",
)
def __repr__(self):
"""
Returns a string with information about the menu node when it is
evaluated on e.g. the interactive Python prompt.
"""
fields = []
if isinstance(self.item, Symbol):
fields.append("menu node for symbol " + self.item.name)
elif isinstance(self.item, Choice):
s = "menu node for choice"
if self.item.name is not None:
s += " " + self.item.name
fields.append(s)
elif self.item == MENU:
fields.append("menu node for menu")
elif self.item == COMMENT:
fields.append("menu node for comment")
elif self.item is None:
fields.append("menu node for if (should not appear in the final "
" tree)")
else:
raise InternalError("unable to determine type in "
"MenuNode.__repr__()")
if self.prompt:
fields.append('prompt "{}" (visibility {})'
.format(self.prompt[0],
TRI_TO_STR[expr_value(self.prompt[1])]))
if isinstance(self.item, Symbol) and self.is_menuconfig:
fields.append("is menuconfig")
fields.append("deps " + TRI_TO_STR[expr_value(self.dep)])
if self.item == MENU:
fields.append("'visible if' deps " + \
TRI_TO_STR[expr_value(self.visibility)])
if isinstance(self.item, (Symbol, Choice)) and self.help is not None:
fields.append("has help")
if self.list:
fields.append("has child")
if self.next:
fields.append("has next")
fields.append("{}:{}".format(self.filename, self.linenr))
return "<{}>".format(", ".join(fields))
def __str__(self):
"""
Returns a string representation of the MenuNode, matching the Kconfig
format.
For Symbol and Choice menu nodes, this function simply calls through to
MenuNode.item.__str__(). For MENU and COMMENT nodes, a Kconfig-like
representation of the menu or comment is returned.
"""
if isinstance(self.item, (Symbol, Choice)):
return self.item.__str__()
if self.item in (MENU, COMMENT):
s = ("menu" if self.item == MENU else "comment") + \
' "{}"\n'.format(escape(self.prompt[0]))
if self.dep is not self.kconfig.y:
s += "\tdepends on {}\n".format(expr_str(self.dep))
if self.item == MENU and self.visibility is not self.kconfig.y:
s += "\tvisible if {}\n".format(expr_str(self.visibility))
return s
# 'if' node. Should never appear in the final tree.
return "if " + expr_str(self.dep)
class KconfigSyntaxError(Exception):
"""
Exception raised for syntax errors.
"""
pass
class InternalError(Exception):
"""
Exception raised for internal errors.
"""
pass
#
# Public functions
#
def expr_value(expr):
"""
Evaluates the expression 'expr' to a tristate value. Returns 0 (n), 1 (m),
or 2 (y).
'expr' must be an already-parsed expression from a Symbol, Choice, or
MenuNode property. To evaluate an expression represented as a string, use
Kconfig.eval_string().
Passing subexpressions of expressions to this function works as expected.
"""
if not isinstance(expr, tuple):
return expr.tri_value
if expr[0] == AND:
v1 = expr_value(expr[1])
# Short-circuit the n case as an optimization (~5% faster
# allnoconfig.py and allyesconfig.py, as of writing)
return 0 if not v1 else min(v1, expr_value(expr[2]))
if expr[0] == OR:
v1 = expr_value(expr[1])
# Short-circuit the y case as an optimization
return 2 if v1 == 2 else max(v1, expr_value(expr[2]))
if expr[0] == NOT:
return 2 - expr_value(expr[1])
if expr[0] in _RELATIONS:
# Implements <, <=, >, >= comparisons as well. These were added to
# kconfig in 31847b67 (kconfig: allow use of relations other than
# (in)equality).
oper, op1, op2 = expr
# If both operands are strings...
if op1.orig_type == STRING and op2.orig_type == STRING:
# ...then compare them lexicographically
comp = _strcmp(op1.str_value, op2.str_value)
else:
# Otherwise, try to compare them as numbers
try:
comp = _sym_to_num(op1) - _sym_to_num(op2)
except ValueError:
# Fall back on a lexicographic comparison if the operands don't
# parse as numbers
comp = _strcmp(op1.str_value, op2.str_value)
if oper == EQUAL: res = comp == 0
elif oper == UNEQUAL: res = comp != 0
elif oper == LESS: res = comp < 0
elif oper == LESS_EQUAL: res = comp <= 0
elif oper == GREATER: res = comp > 0
elif oper == GREATER_EQUAL: res = comp >= 0
return 2*res
_internal_error("Internal error while evaluating expression: "
"unknown operation {}.".format(expr[0]))
def expr_str(expr):
"""
Returns the string representation of the expression 'expr', as in a Kconfig
file.
Passing subexpressions of expressions to this function works as expected.
"""
if not isinstance(expr, tuple):
if isinstance(expr, Choice):
if expr.name is not None:
return "<choice {}>".format(expr.name)
return "<choice>"
# Symbol
if expr.is_constant:
return '"{}"'.format(escape(expr.name))
return expr.name
if expr[0] == NOT:
if isinstance(expr[1], Symbol):
return "!" + expr_str(expr[1])
return "!({})".format(expr_str(expr[1]))
if expr[0] == AND:
return "{} && {}".format(_format_and_op(expr[1]),
_format_and_op(expr[2]))
if expr[0] == OR:
return "{} || {}".format(expr_str(expr[1]), expr_str(expr[2]))
# Relation
return "{} {} {}".format(expr_str(expr[1]),
_REL_TO_STR[expr[0]],
expr_str(expr[2]))
def escape(s):
r"""
Escapes the string 's' in the same fashion as is done for display in
Kconfig format and when writing strings to a .config file. " and \ are
replaced by \" and \\, respectively.
"""
# \ must be escaped before " to avoid double escaping
return s.replace("\\", r"\\").replace('"', r'\"')
# unescape() helper
_unescape_re_sub = re.compile(r"\\(.)").sub
def unescape(s):
r"""
Unescapes the string 's'. \ followed by any character is replaced with just
that character. Used internally when reading .config files.
"""
return _unescape_re_sub(r"\1", s)
#
# Internal functions
#
def _get_visibility(sc):
"""
Symbols and Choices have a "visibility" that acts as an upper bound on the
values a user can set for them, corresponding to the visibility in e.g.
'make menuconfig'. This function calculates the visibility for the Symbol
or Choice 'sc' -- the logic is nearly identical.
"""
vis = 0
for node in sc.nodes:
if node.prompt:
vis = max(vis, expr_value(node.prompt[1]))
if isinstance(sc, Symbol) and sc.choice:
if sc.choice.orig_type == TRISTATE and sc.orig_type != TRISTATE and \
sc.choice.tri_value != 2:
# Non-tristate choice symbols are only visible in y mode
return 0
if sc.orig_type == TRISTATE and vis == 1 and sc.choice.tri_value == 2:
# Choice symbols with m visibility are not visible in y mode
return 0
# Promote m to y if we're dealing with a non-tristate (possibly due to
# modules being disabled)
if vis == 1 and sc.type != TRISTATE:
return 2
return vis
def _make_depend_on(sym, expr):
"""
Adds 'sym' as a dependency to all symbols in 'expr'. Constant symbols in
'expr' are skipped as they can never change value anyway.
"""
if not isinstance(expr, tuple):
if not expr.is_constant:
expr._dependents.add(sym)
elif expr[0] in (AND, OR):
_make_depend_on(sym, expr[1])
_make_depend_on(sym, expr[2])
elif expr[0] == NOT:
_make_depend_on(sym, expr[1])
elif expr[0] in _RELATIONS:
if not expr[1].is_constant:
expr[1]._dependents.add(sym)
if not expr[2].is_constant:
expr[2]._dependents.add(sym)
else:
_internal_error("Internal error while fetching symbols from an "
"expression with token stream {}.".format(expr))
def _format_and_op(expr):
"""
expr_str() helper. Returns the string representation of 'expr', which is
assumed to be an operand to AND, with parentheses added if needed.
"""
if isinstance(expr, tuple) and expr[0] == OR:
return "({})".format(expr_str(expr))
return expr_str(expr)
def _indentation(line):
"""
Returns the length of the line's leading whitespace, treating tab stops as
being spaced 8 characters apart.
"""
line = line.expandtabs()
return len(line) - len(line.lstrip())
def _dedent_rstrip(line, indent):
r"""
De-indents 'line' by 'indent' spaces and rstrip()s it to remove any
newlines (which gets rid of other trailing whitespace too, but that's
fine).
Used to prepare help text lines in a speedy way: The [indent:] might
already remove trailing newlines for lines shorter than indent (e.g. empty
lines). The rstrip() makes it consistent, meaning we can join the lines
with "\n" later.
"""
return line.expandtabs()[indent:].rstrip()
def _is_base_n(s, n):
try:
int(s, n)
return True
except ValueError:
return False
def _strcmp(s1, s2):
"""
strcmp()-alike that returns -1, 0, or 1.
"""
return (s1 > s2) - (s1 < s2)
def _sym_to_num(sym):
"""
expr_value() helper for converting a symbol to a number. Raises ValueError
for symbols that can't be converted.
"""
# For BOOL and TRISTATE, n/m/y count as 0/1/2. This mirrors 9059a3493ef
# ("kconfig: fix relational operators for bool and tristate symbols") in
# the C implementation.
return sym.tri_value if sym.orig_type in (BOOL, TRISTATE) else \
int(sym.str_value, _TYPE_TO_BASE[sym.orig_type])
def _stderr_msg(msg, filename, linenr):
if filename is not None:
msg = "{}:{}: {}".format(filename, linenr, msg)
sys.stderr.write(msg + "\n")
def _internal_error(msg):
raise InternalError(
msg +
"\nSorry! You may want to send an email to ulfalizer a.t Google's "
"email service to tell me about this. Include the message above and "
"the stack trace and describe what you were doing.")
# Printing functions
def _sym_choice_str(sc):
"""
Symbol/choice __str__() implementation. These have many properties in
common, so it makes sense to handle them together.
"""
lines = []
def indent_add(s):
lines.append("\t" + s)
# We print the prompt(s) and help text(s) too as a convenience, even though
# they're actually part of the MenuNode. If a symbol or choice is defined
# in multiple locations (has more than one MenuNode), we output one
# statement for each location, and print all the properties that belong to
# the symbol/choice itself only at the first location. This gives output
# that would function if fed to a Kconfig parser, even for such
# symbols/choices (choices defined in multiple locations gets a bit iffy
# since they also have child nodes, though I've never seen such a choice).
if not sc.nodes:
return ""
for node in sc.nodes:
if isinstance(sc, Symbol):
if node.is_menuconfig:
lines.append("menuconfig " + sc.name)
else:
lines.append("config " + sc.name)
else:
if sc.name is None:
lines.append("choice")
else:
lines.append("choice " + sc.name)
if node is sc.nodes[0] and sc.orig_type != UNKNOWN:
indent_add(TYPE_TO_STR[sc.orig_type])
if node.prompt:
prompt, cond = node.prompt
prompt_str = 'prompt "{}"'.format(escape(prompt))
if cond is not sc.kconfig.y:
prompt_str += " if " + expr_str(cond)
indent_add(prompt_str)
if node is sc.nodes[0]:
if isinstance(sc, Symbol):
if sc.is_allnoconfig_y:
indent_add("option allnoconfig_y")
if sc is sc.kconfig.defconfig_list:
indent_add("option defconfig_list")
if sc.env_var is not None:
indent_add('option env="{}"'.format(sc.env_var))
if sc is sc.kconfig.modules:
indent_add("option modules")
if isinstance(sc, Symbol):
for low, high, cond in sc.ranges:
range_string = "range {} {}" \
.format(expr_str(low), expr_str(high))
if cond is not sc.kconfig.y:
range_string += " if " + expr_str(cond)
indent_add(range_string)
for default, cond in sc.defaults:
default_string = "default " + expr_str(default)
if cond is not sc.kconfig.y:
default_string += " if " + expr_str(cond)
indent_add(default_string)
if isinstance(sc, Choice) and sc.is_optional:
indent_add("optional")
if isinstance(sc, Symbol):
for select, cond in sc.selects:
select_string = "select " + select.name
if cond is not sc.kconfig.y:
select_string += " if " + expr_str(cond)
indent_add(select_string)
for imply, cond in sc.implies:
imply_string = "imply " + imply.name
if cond is not sc.kconfig.y:
imply_string += " if " + expr_str(cond)
indent_add(imply_string)
if node.help is not None:
indent_add("help")
for line in node.help.splitlines():
indent_add(" " + line)
# Add a blank line if there are more nodes to print
if node is not sc.nodes[-1]:
lines.append("")
return "\n".join(lines) + "\n"
def _name_and_loc_str(sc):
"""
Helper for giving the symbol/choice name and location(s) in e.g.
warnings
"""
name = sc.name or "<choice>"
if not sc.nodes:
return name + " (undefined)"
return "{} (defined at {})".format(
name,
", ".join("{}:{}".format(node.filename, node.linenr)
for node in sc.nodes))
# Menu manipulation
def _expr_depends_on(expr, sym):
"""
Reimplementation of expr_depends_symbol() from mconf.c. Used to
determine if a submenu should be implicitly created. This also influences
which items inside choice statements are considered choice items.
"""
if not isinstance(expr, tuple):
return expr is sym
if expr[0] in (EQUAL, UNEQUAL):
# Check for one of the following:
# sym = m/y, m/y = sym, sym != n, n != sym
left, right = expr[1:]
if right is sym:
left, right = right, left
if left is not sym:
return False
return (expr[0] == EQUAL and right is sym.kconfig.m or \
right is sym.kconfig.y) or \
(expr[0] == UNEQUAL and right is sym.kconfig.n)
if expr[0] == AND:
return _expr_depends_on(expr[1], sym) or \
_expr_depends_on(expr[2], sym)
return False
def _has_auto_menu_dep(node1, node2):
"""
Returns True if node2 has an "automatic menu dependency" on node1. If node2
has a prompt, we check its condition. Otherwise, we look directly at
node2.dep.
"""
if node2.prompt:
return _expr_depends_on(node2.prompt[1], node1.item)
# If we have no prompt, use the menu node dependencies instead
return _expr_depends_on(node2.dep, node1.item)
def _flatten(node):
"""
"Flattens" menu nodes without prompts (e.g. 'if' nodes and non-visible
symbols with children from automatic menu creation) so that their children
appear after them instead. This gives a clean menu structure with no
unexpected "jumps" in the indentation.
"""
while node:
if node.list and (not node.prompt or node.prompt[0] == ""):
last_node = node.list
while 1:
last_node.parent = node.parent
if not last_node.next:
break
last_node = last_node.next
last_node.next = node.next
node.next = node.list
node.list = None
node = node.next
def _remove_ifs(node):
"""
Removes 'if' nodes (which can be recognized by MenuNode.item being None),
which are assumed to already have been flattened. The C implementation
doesn't bother to do this, but we expose the menu tree directly, and it
makes it nicer to work with.
"""
first = node.list
while first and first.item is None:
first = first.next
cur = first
while cur:
if cur.next and cur.next.item is None:
cur.next = cur.next.next
cur = cur.next
node.list = first
def _finalize_choice(node):
"""
Finalizes a choice, marking each symbol whose menu node has the choice as
the parent as a choice symbol, and automatically determining types if not
specified.
"""
choice = node.item
cur = node.list
while cur:
if isinstance(cur.item, Symbol):
cur.item.choice = choice
choice.syms.append(cur.item)
cur = cur.next
# If no type is specified for the choice, its type is that of
# the first choice item with a specified type
if choice.orig_type == UNKNOWN:
for item in choice.syms:
if item.orig_type != UNKNOWN:
choice.orig_type = item.orig_type
break
# Each choice item of UNKNOWN type gets the type of the choice
for sym in choice.syms:
if sym.orig_type == UNKNOWN:
sym.orig_type = choice.orig_type
def _finalize_tree(node):
"""
Creates implicit menus from dependencies (see kconfig-language.txt),
removes 'if' nodes, and finalizes choices. This pretty closely mirrors
menu_finalize() from the C implementation, though we propagate dependencies
during parsing instead.
"""
if node.list:
# The menu node is a choice, menu, or if. Finalize each child in it.
cur = node.list
while cur:
_finalize_tree(cur)
cur = cur.next
elif isinstance(node.item, Symbol):
# The menu node is a symbol. See if we can create an implicit menu
# rooted at it and finalize each child in that menu if so, like for the
# choice/menu/if case above.
cur = node
while cur.next and _has_auto_menu_dep(node, cur.next):
# This also makes implicit submenu creation work recursively, with
# implicit menus inside implicit menus
_finalize_tree(cur.next)
cur = cur.next
cur.parent = node
if cur is not node:
# Found symbols that should go in an implicit submenu. Tilt them up
# above us.
node.list = node.next
node.next = cur.next
cur.next = None
_check_sym_sanity(node.item)
if node.list:
# We have a node with child nodes where the child nodes are now
# individually finalized. Do final steps to finalize this "level" in
# the menu tree.
_flatten(node.list)
_remove_ifs(node)
# Empty choices (node.list None) are possible, so this needs to go outside
if isinstance(node.item, Choice):
_finalize_choice(node)
_check_choice_sanity(node.item)
def _check_sym_sanity(sym):
"""
Checks various symbol properties that are handiest to check after parsing.
Only generates errors and warnings.
"""
if sym.orig_type in (BOOL, TRISTATE):
# A helper function could be factored out here, but keep it
# speedy/straightforward for now. bool/tristate symbols are by far the
# most common, and most lack selects and implies.
for target_sym, _ in sym.selects:
if target_sym.orig_type not in (BOOL, TRISTATE, UNKNOWN):
sym.kconfig._warn("{} selects the {} symbol {}, which is not "
"bool or tristate"
.format(_name_and_loc_str(sym),
TYPE_TO_STR[target_sym.orig_type],
_name_and_loc_str(target_sym)))
for target_sym, _ in sym.implies:
if target_sym.orig_type not in (BOOL, TRISTATE, UNKNOWN):
sym.kconfig._warn("{} implies the {} symbol {}, which is not "
"bool or tristate"
.format(_name_and_loc_str(sym),
TYPE_TO_STR[target_sym.orig_type],
_name_and_loc_str(target_sym)))
elif sym.orig_type in (STRING, INT, HEX):
for default, _ in sym.defaults:
if not isinstance(default, Symbol):
raise KconfigSyntaxError(
"the {} symbol {} has a malformed default {} -- expected "
"a single symbol"
.format(TYPE_TO_STR[sym.orig_type], _name_and_loc_str(sym),
expr_str(default)))
if sym.orig_type in (INT, HEX) and \
not _int_hex_value_is_sane(default, sym.orig_type):
sym.kconfig._warn("the {0} symbol {1} has a non-{0} default {2}"
.format(TYPE_TO_STR[sym.orig_type],
_name_and_loc_str(sym),
_name_and_loc_str(default)))
if sym.selects or sym.implies:
sym.kconfig._warn("the {} symbol {} has selects or implies"
.format(TYPE_TO_STR[sym.orig_type],
_name_and_loc_str(sym)))
else: # UNKNOWN
sym.kconfig._warn("{} defined without a type"
.format(_name_and_loc_str(sym)))
if sym.ranges:
if sym.orig_type not in (INT, HEX):
sym.kconfig._warn(
"the {} symbol {} has ranges, but is not int or hex"
.format(TYPE_TO_STR[sym.orig_type], _name_and_loc_str(sym)))
else:
for low, high, _ in sym.ranges:
if not _int_hex_value_is_sane(low, sym.orig_type) or \
not _int_hex_value_is_sane(high, sym.orig_type):
sym.kconfig._warn("the {0} symbol {1} has a non-{0} range "
"[{2}, {3}]"
.format(TYPE_TO_STR[sym.orig_type],
_name_and_loc_str(sym),
_name_and_loc_str(low),
_name_and_loc_str(high)))
def _int_hex_value_is_sane(sym, type_):
# 'not sym.nodes' implies a constant or undefined symbol, e.g. a plain
# "123"
return (not sym.nodes and _is_base_n(sym.name, _TYPE_TO_BASE[type_])) or \
sym.orig_type == type_
def _check_choice_sanity(choice):
"""
Checks various choice properties that are handiest to check after parsing.
Only generates errors and warnings.
"""
if choice.orig_type not in (BOOL, TRISTATE):
choice.kconfig._warn("{} defined with type {}"
.format(_name_and_loc_str(choice),
TYPE_TO_STR[choice.orig_type]))
for node in choice.nodes:
if node.prompt:
break
else:
choice.kconfig._warn("{} defined without a prompt"
.format(_name_and_loc_str(choice)))
for default, _ in choice.defaults:
if not isinstance(default, Symbol):
raise KconfigSyntaxError(
"{} has a malformed default {}"
.format(_name_and_loc_str(choice), expr_str(default)))
if default.choice is not choice:
choice.kconfig._warn("the default selection {} of {} is not "
"contained in the choice"
.format(_name_and_loc_str(default),
_name_and_loc_str(choice)))
for sym in choice.syms:
if sym.defaults:
choice.kconfig._warn("default on the choice symbol {} will have "
"no effect"
.format(_name_and_loc_str(sym)))
for node in sym.nodes:
if node.parent.item is choice:
if not node.prompt:
choice.kconfig._warn("the choice symbol {} has no prompt"
.format(_name_and_loc_str(sym)))
elif node.prompt:
choice.kconfig._warn("the choice symbol {} is defined with a "
"prompt outside the choice"
.format(_name_and_loc_str(sym)))
#
# Public global constants
#
# Integers representing symbol types
(
BOOL,
HEX,
INT,
STRING,
TRISTATE,
UNKNOWN
) = range(6)
# Integers representing expression types
(
AND,
OR,
NOT,
EQUAL,
UNEQUAL,
LESS,
LESS_EQUAL,
GREATER,
GREATER_EQUAL,
) = range(9)
# Integers representing menu and comment menu nodes
(
MENU,
COMMENT,
) = range(2)
# Converts a symbol/choice type to a string
TYPE_TO_STR = {
UNKNOWN: "unknown",
BOOL: "bool",
TRISTATE: "tristate",
STRING: "string",
HEX: "hex",
INT: "int",
}
TRI_TO_STR = {
0: "n",
1: "m",
2: "y",
}
STR_TO_TRI = {
"n": 0,
"m": 1,
"y": 2,
}
#
# Internal global constants
#
# Tokens
(
_T_ALLNOCONFIG_Y,
_T_AND,
_T_BOOL,
_T_CHOICE,
_T_CLOSE_PAREN,
_T_COMMENT,
_T_CONFIG,
_T_DEFAULT,
_T_DEFCONFIG_LIST,
_T_DEF_BOOL,
_T_DEF_TRISTATE,
_T_DEPENDS,
_T_ENDCHOICE,
_T_ENDIF,
_T_ENDMENU,
_T_ENV,
_T_EQUAL,
_T_GREATER,
_T_GREATER_EQUAL,
_T_HELP,
_T_HEX,
_T_IF,
_T_IMPLY,
_T_INT,
_T_LESS,
_T_LESS_EQUAL,
_T_MAINMENU,
_T_MENU,
_T_MENUCONFIG,
_T_MODULES,
_T_NOT,
_T_ON,
_T_OPEN_PAREN,
_T_OPTION,
_T_OPTIONAL,
_T_OR,
_T_PROMPT,
_T_RANGE,
_T_SELECT,
_T_SOURCE,
_T_STRING,
_T_TRISTATE,
_T_UNEQUAL,
_T_VISIBLE,
) = range(44)
# Keyword to token map, with the get() method assigned directly as a small
# optimization
_get_keyword = {
"allnoconfig_y": _T_ALLNOCONFIG_Y,
"bool": _T_BOOL,
"boolean": _T_BOOL,
"choice": _T_CHOICE,
"comment": _T_COMMENT,
"config": _T_CONFIG,
"def_bool": _T_DEF_BOOL,
"def_tristate": _T_DEF_TRISTATE,
"default": _T_DEFAULT,
"defconfig_list": _T_DEFCONFIG_LIST,
"depends": _T_DEPENDS,
"endchoice": _T_ENDCHOICE,
"endif": _T_ENDIF,
"endmenu": _T_ENDMENU,
"env": _T_ENV,
"help": _T_HELP,
"hex": _T_HEX,
"if": _T_IF,
"imply": _T_IMPLY,
"int": _T_INT,
"mainmenu": _T_MAINMENU,
"menu": _T_MENU,
"menuconfig": _T_MENUCONFIG,
"modules": _T_MODULES,
"on": _T_ON,
"option": _T_OPTION,
"optional": _T_OPTIONAL,
"prompt": _T_PROMPT,
"range": _T_RANGE,
"select": _T_SELECT,
"source": _T_SOURCE,
"string": _T_STRING,
"tristate": _T_TRISTATE,
"visible": _T_VISIBLE,
}.get
# Tokens after which identifier-like lexemes are treated as strings. _T_CHOICE
# is included to avoid symbols being registered for named choices.
_STRING_LEX = frozenset((
_T_BOOL,
_T_CHOICE,
_T_COMMENT,
_T_HEX,
_T_INT,
_T_MAINMENU,
_T_MENU,
_T_PROMPT,
_T_SOURCE,
_T_STRING,
_T_TRISTATE,
))
# Tokens for types, excluding def_bool, def_tristate, etc., for quick
# checks during parsing
_TYPE_TOKENS = frozenset((
_T_BOOL,
_T_TRISTATE,
_T_INT,
_T_HEX,
_T_STRING,
))
# Use ASCII regex matching on Python 3. It's already the default on Python 2.
_RE_ASCII = 0 if sys.version_info[0] < 3 else re.ASCII
# Note: This hack is no longer needed as of upstream commit c226456
# (kconfig: warn of unhandled characters in Kconfig commands). It
# is kept around for backwards compatibility.
#
# The initial word on a line is parsed specially. Let
# command_chars = [A-Za-z0-9_]. Then
# - leading non-command_chars characters are ignored, and
# - the first token consists the following one or more
# command_chars characters.
# This is why things like "----help--" are accepted.
#
# In addition to the initial token, the regex also matches trailing whitespace
# so that we can jump straight to the next token (or to the end of the line if
# there's just a single token).
#
# As an optimization, this regex fails to match for lines containing just a
# comment.
_initial_token_re_match = \
re.compile(r"[^A-Za-z0-9_#]*([A-Za-z0-9_]+)\s*", _RE_ASCII).match
# Matches an identifier/keyword, also eating trailing whitespace
_id_keyword_re_match = re.compile(r"([A-Za-z0-9_/.-]+)\s*", _RE_ASCII).match
# Regular expression for finding $-references to symbols in strings
_sym_ref_re_search = re.compile(r"\$([A-Za-z0-9_]+)", _RE_ASCII).search
# Matches a valid right-hand side for an assignment to a string symbol in a
# .config file, including escaped characters. Extracts the contents.
_conf_string_re_match = re.compile(r'"((?:[^\\"]|\\.)*)"', _RE_ASCII).match
# Token to type mapping
_TOKEN_TO_TYPE = {
_T_BOOL: BOOL,
_T_DEF_BOOL: BOOL,
_T_DEF_TRISTATE: TRISTATE,
_T_HEX: HEX,
_T_INT: INT,
_T_STRING: STRING,
_T_TRISTATE: TRISTATE,
}
# Constant representing that there's no cached choice selection. This is
# distinct from a cached None (no selection). We create a unique object (any
# will do) for it so we can test with 'is'.
_NO_CACHED_SELECTION = object()
# Used in comparisons. 0 means the base is inferred from the format of the
# string.
_TYPE_TO_BASE = {
HEX: 16,
INT: 10,
STRING: 0,
UNKNOWN: 0,
}
_RELATIONS = frozenset((
EQUAL,
UNEQUAL,
LESS,
LESS_EQUAL,
GREATER,
GREATER_EQUAL,
))
# Token to relation (=, !=, <, ...) mapping
_TOKEN_TO_REL = {
_T_EQUAL: EQUAL,
_T_GREATER: GREATER,
_T_GREATER_EQUAL: GREATER_EQUAL,
_T_LESS: LESS,
_T_LESS_EQUAL: LESS_EQUAL,
_T_UNEQUAL: UNEQUAL,
}
_REL_TO_STR = {
EQUAL: "=",
GREATER: ">",
GREATER_EQUAL: ">=",
LESS: "<",
LESS_EQUAL: "<=",
UNEQUAL: "!=",
}
# Enable universal newlines mode on Python 2 to ease interoperability between
# Linux and Windows. It's already the default on Python 3.
#
# The "U" flag would currently work for both Python 2 and 3, but it's
# deprecated on Python 3, so play it future-safe.
#
# A simpler solution would be to use io.open(), which defaults to universal
# newlines on both Python 2 and 3 (and is an alias for open() on Python 3), but
# it's appreciably slower on Python 2:
#
# Parsing x86 Kconfigs on Python 2
#
# with open(..., "rU"):
#
# real 0m0.930s
# user 0m0.905s
# sys 0m0.025s
#
# with io.open():
#
# real 0m1.069s
# user 0m1.040s
# sys 0m0.029s
#
# There's no appreciable performance difference between "r" and "rU" for
# parsing performance on Python 2.
_UNIVERSAL_NEWLINES_MODE = "rU" if sys.version_info[0] < 3 else "r"