#!/usr/bin/env python
# encoding: utf-8
# Thomas Nagy, 2006-2018 (ita)
"""
C/C++ preprocessor for finding dependencies
Reasons for using the Waf preprocessor by default
#. Some c/c++ extensions (Qt) require a custom preprocessor for obtaining the dependencies (.moc files)
#. Not all compilers provide .d files for obtaining the dependencies (portability)
#. A naive file scanner will not catch the constructs such as "#include foo()"
#. A naive file scanner will catch unnecessary dependencies (change an unused header -> recompile everything)
Regarding the speed concerns:
* the preprocessing is performed only when files must be compiled
* the macros are evaluated only for #if/#elif/#include
* system headers are not scanned by default
Now if you do not want the Waf preprocessor, the tool +gccdeps* uses the .d files produced
during the compilation to track the dependencies (useful when used with the boost libraries).
It only works with gcc >= 4.4 though.
A dumb preprocessor is also available in the tool *c_dumbpreproc*
"""
# TODO: more varargs, pragma once
import re, string, traceback
from waflib import Logs, Utils, Errors
[docs]class PreprocError(Errors.WafError):
pass
FILE_CACHE_SIZE = 100000
LINE_CACHE_SIZE = 100000
POPFILE = '-'
"Constant representing a special token used in :py:meth:`waflib.Tools.c_preproc.c_parser.start` iteration to switch to a header read previously"
recursion_limit = 150
"Limit on the amount of files to read in the dependency scanner"
go_absolute = False
"Set to True to track headers on files in /usr/include, else absolute paths are ignored (but it becomes very slow)"
standard_includes = ['/usr/local/include', '/usr/include']
if Utils.is_win32:
standard_includes = []
use_trigraphs = 0
"""Apply trigraph rules (False by default)"""
# obsolete, do not use
strict_quotes = 0
g_optrans = {
'not':'!',
'not_eq':'!',
'and':'&&',
'and_eq':'&=',
'or':'||',
'or_eq':'|=',
'xor':'^',
'xor_eq':'^=',
'bitand':'&',
'bitor':'|',
'compl':'~',
}
"""Operators such as and/or/xor for c++. Set an empty dict to disable."""
# ignore #warning and #error
re_lines = re.compile(
'^[ \t]*(?:#|%:)[ \t]*(ifdef|ifndef|if|else|elif|endif|include|import|define|undef|pragma)[ \t]*(.*)\r*$',
re.IGNORECASE | re.MULTILINE)
"""Match #include lines"""
re_mac = re.compile(r"^[a-zA-Z_]\w*")
"""Match macro definitions"""
re_fun = re.compile('^[a-zA-Z_][a-zA-Z0-9_]*[(]')
"""Match macro functions"""
re_pragma_once = re.compile(r'^\s*once\s*', re.IGNORECASE)
"""Match #pragma once statements"""
re_nl = re.compile('\\\\\r*\n', re.MULTILINE)
"""Match newlines"""
re_cpp = re.compile(r'//.*?$|/\*.*?\*/|\'(?:\\.|[^\\\'])*\'|"(?:\\.|[^\\"])*"', re.DOTALL | re.MULTILINE )
"""Filter C/C++ comments"""
trig_def = [('??'+a, b) for a, b in zip("=-/!'()<>", r'#~\|^[]{}')]
"""Trigraph definitions"""
chr_esc = {'0':0, 'a':7, 'b':8, 't':9, 'n':10, 'f':11, 'v':12, 'r':13, '\\':92, "'":39}
"""Escape characters"""
NUM = 'i'
"""Number token"""
OP = 'O'
"""Operator token"""
IDENT = 'T'
"""Identifier token"""
STR = 's'
"""String token"""
CHAR = 'c'
"""Character token"""
tok_types = [NUM, STR, IDENT, OP]
"""Token types"""
exp_types = [
r"""0[xX](?P<hex>[a-fA-F0-9]+)(?P<qual1>[uUlL]*)|L*?'(?P<char>(\\.|[^\\'])+)'|(?P<n1>\d+)[Ee](?P<exp0>[+-]*?\d+)(?P<float0>[fFlL]*)|(?P<n2>\d*\.\d+)([Ee](?P<exp1>[+-]*?\d+))?(?P<float1>[fFlL]*)|(?P<n4>\d+\.\d*)([Ee](?P<exp2>[+-]*?\d+))?(?P<float2>[fFlL]*)|(?P<oct>0*)(?P<n0>\d+)(?P<qual2>[uUlL]*)""",
r'L?"([^"\\]|\\.)*"',
r'[a-zA-Z_]\w*',
r'%:%:|<<=|>>=|\.\.\.|<<|<%|<:|<=|>>|>=|\+\+|\+=|--|->|-=|\*=|/=|%:|%=|%>|==|&&|&=|\|\||\|=|\^=|:>|!=|##|[\(\)\{\}\[\]<>\?\|\^\*\+&=:!#;,%/\-\?\~\.]',
]
"""Expression types"""
re_clexer = re.compile('|'.join(["(?P<%s>%s)" % (name, part) for name, part in zip(tok_types, exp_types)]), re.M)
"""Match expressions into tokens"""
accepted = 'a'
"""Parser state is *accepted*"""
ignored = 'i'
"""Parser state is *ignored*, for example preprocessor lines in an #if 0 block"""
undefined = 'u'
"""Parser state is *undefined* at the moment"""
skipped = 's'
"""Parser state is *skipped*, for example preprocessor lines in a #elif 0 block"""
[docs]def repl(m):
"""Replace function used with :py:attr:`waflib.Tools.c_preproc.re_cpp`"""
s = m.group()
if s[0] == '/':
return ' '
return s
prec = {}
"""
Operator precedence rules required for parsing expressions of the form::
#if 1 && 2 != 0
"""
ops = ['* / %', '+ -', '<< >>', '< <= >= >', '== !=', '& | ^', '&& ||', ',']
for x, syms in enumerate(ops):
for u in syms.split():
prec[u] = x
[docs]def reduce_nums(val_1, val_2, val_op):
"""
Apply arithmetic rules to compute a result
:param val1: input parameter
:type val1: int or string
:param val2: input parameter
:type val2: int or string
:param val_op: C operator in *+*, */*, *-*, etc
:type val_op: string
:rtype: int
"""
#print val_1, val_2, val_op
# now perform the operation, make certain a and b are numeric
try:
a = 0 + val_1
except TypeError:
a = int(val_1)
try:
b = 0 + val_2
except TypeError:
b = int(val_2)
d = val_op
if d == '%':
c = a % b
elif d=='+':
c = a + b
elif d=='-':
c = a - b
elif d=='*':
c = a * b
elif d=='/':
c = a / b
elif d=='^':
c = a ^ b
elif d=='==':
c = int(a == b)
elif d=='|' or d == 'bitor':
c = a | b
elif d=='||' or d == 'or' :
c = int(a or b)
elif d=='&' or d == 'bitand':
c = a & b
elif d=='&&' or d == 'and':
c = int(a and b)
elif d=='!=' or d == 'not_eq':
c = int(a != b)
elif d=='^' or d == 'xor':
c = int(a^b)
elif d=='<=':
c = int(a <= b)
elif d=='<':
c = int(a < b)
elif d=='>':
c = int(a > b)
elif d=='>=':
c = int(a >= b)
elif d=='<<':
c = a << b
elif d=='>>':
c = a >> b
else:
c = 0
return c
[docs]def get_num(lst):
"""
Try to obtain a number from a list of tokens. The token types are defined in :py:attr:`waflib.Tools.ccroot.tok_types`.
:param lst: list of preprocessor tokens
:type lst: list of tuple (tokentype, value)
:return: a pair containing the number and the rest of the list
:rtype: tuple(value, list)
"""
if not lst:
raise PreprocError('empty list for get_num')
(p, v) = lst[0]
if p == OP:
if v == '(':
count_par = 1
i = 1
while i < len(lst):
(p, v) = lst[i]
if p == OP:
if v == ')':
count_par -= 1
if count_par == 0:
break
elif v == '(':
count_par += 1
i += 1
else:
raise PreprocError('rparen expected %r' % lst)
(num, _) = get_term(lst[1:i])
return (num, lst[i+1:])
elif v == '+':
return get_num(lst[1:])
elif v == '-':
num, lst = get_num(lst[1:])
return (reduce_nums('-1', num, '*'), lst)
elif v == '!':
num, lst = get_num(lst[1:])
return (int(not int(num)), lst)
elif v == '~':
num, lst = get_num(lst[1:])
return (~ int(num), lst)
else:
raise PreprocError('Invalid op token %r for get_num' % lst)
elif p == NUM:
return v, lst[1:]
elif p == IDENT:
# all macros should have been replaced, remaining identifiers eval to 0
return 0, lst[1:]
else:
raise PreprocError('Invalid token %r for get_num' % lst)
[docs]def get_term(lst):
"""
Evaluate an expression recursively, for example::
1+1+1 -> 2+1 -> 3
:param lst: list of tokens
:type lst: list of tuple(token, value)
:return: the value and the remaining tokens
:rtype: value, list
"""
if not lst:
raise PreprocError('empty list for get_term')
num, lst = get_num(lst)
if not lst:
return (num, [])
(p, v) = lst[0]
if p == OP:
if v == ',':
# skip
return get_term(lst[1:])
elif v == '?':
count_par = 0
i = 1
while i < len(lst):
(p, v) = lst[i]
if p == OP:
if v == ')':
count_par -= 1
elif v == '(':
count_par += 1
elif v == ':':
if count_par == 0:
break
i += 1
else:
raise PreprocError('rparen expected %r' % lst)
if int(num):
return get_term(lst[1:i])
else:
return get_term(lst[i+1:])
else:
num2, lst = get_num(lst[1:])
if not lst:
# no more tokens to process
num2 = reduce_nums(num, num2, v)
return get_term([(NUM, num2)] + lst)
# operator precedence
p2, v2 = lst[0]
if p2 != OP:
raise PreprocError('op expected %r' % lst)
if prec[v2] >= prec[v]:
num2 = reduce_nums(num, num2, v)
return get_term([(NUM, num2)] + lst)
else:
num3, lst = get_num(lst[1:])
num3 = reduce_nums(num2, num3, v2)
return get_term([(NUM, num), (p, v), (NUM, num3)] + lst)
raise PreprocError('cannot reduce %r' % lst)
[docs]def reduce_eval(lst):
"""
Take a list of tokens and output true or false for #if/#elif conditions.
:param lst: a list of tokens
:type lst: list of tuple(token, value)
:return: a token
:rtype: tuple(NUM, int)
"""
num, lst = get_term(lst)
return (NUM, num)
[docs]def stringize(lst):
"""
Merge a list of tokens into a string
:param lst: a list of tokens
:type lst: list of tuple(token, value)
:rtype: string
"""
lst = [str(v2) for (p2, v2) in lst]
return "".join(lst)
[docs]def paste_tokens(t1, t2):
"""
Token pasting works between identifiers, particular operators, and identifiers and numbers::
a ## b -> ab
> ## = -> >=
a ## 2 -> a2
:param t1: token
:type t1: tuple(type, value)
:param t2: token
:type t2: tuple(type, value)
"""
p1 = None
if t1[0] == OP and t2[0] == OP:
p1 = OP
elif t1[0] == IDENT and (t2[0] == IDENT or t2[0] == NUM):
p1 = IDENT
elif t1[0] == NUM and t2[0] == NUM:
p1 = NUM
if not p1:
raise PreprocError('tokens do not make a valid paste %r and %r' % (t1, t2))
return (p1, t1[1] + t2[1])
[docs]def reduce_tokens(lst, defs, ban=[]):
"""
Replace the tokens in lst, using the macros provided in defs, and a list of macros that cannot be re-applied
:param lst: list of tokens
:type lst: list of tuple(token, value)
:param defs: macro definitions
:type defs: dict
:param ban: macros that cannot be substituted (recursion is not allowed)
:type ban: list of string
:return: the new list of tokens
:rtype: value, list
"""
i = 0
while i < len(lst):
(p, v) = lst[i]
if p == IDENT and v == "defined":
del lst[i]
if i < len(lst):
(p2, v2) = lst[i]
if p2 == IDENT:
if v2 in defs:
lst[i] = (NUM, 1)
else:
lst[i] = (NUM, 0)
elif p2 == OP and v2 == '(':
del lst[i]
(p2, v2) = lst[i]
del lst[i] # remove the ident, and change the ) for the value
if v2 in defs:
lst[i] = (NUM, 1)
else:
lst[i] = (NUM, 0)
else:
raise PreprocError('Invalid define expression %r' % lst)
elif p == IDENT and v in defs:
if isinstance(defs[v], str):
a, b = extract_macro(defs[v])
defs[v] = b
macro_def = defs[v]
to_add = macro_def[1]
if isinstance(macro_def[0], list):
# macro without arguments
del lst[i]
accu = to_add[:]
reduce_tokens(accu, defs, ban+[v])
for tmp in accu:
lst.insert(i, tmp)
i += 1
else:
# collect the arguments for the funcall
args = []
del lst[i]
if i >= len(lst):
raise PreprocError('expected ( after %r (got nothing)' % v)
(p2, v2) = lst[i]
if p2 != OP or v2 != '(':
raise PreprocError('expected ( after %r' % v)
del lst[i]
one_param = []
count_paren = 0
while i < len(lst):
p2, v2 = lst[i]
del lst[i]
if p2 == OP and count_paren == 0:
if v2 == '(':
one_param.append((p2, v2))
count_paren += 1
elif v2 == ')':
if one_param:
args.append(one_param)
break
elif v2 == ',':
if not one_param:
raise PreprocError('empty param in funcall %r' % v)
args.append(one_param)
one_param = []
else:
one_param.append((p2, v2))
else:
one_param.append((p2, v2))
if v2 == '(':
count_paren += 1
elif v2 == ')':
count_paren -= 1
else:
raise PreprocError('malformed macro')
# substitute the arguments within the define expression
accu = []
arg_table = macro_def[0]
j = 0
while j < len(to_add):
(p2, v2) = to_add[j]
if p2 == OP and v2 == '#':
# stringize is for arguments only
if j+1 < len(to_add) and to_add[j+1][0] == IDENT and to_add[j+1][1] in arg_table:
toks = args[arg_table[to_add[j+1][1]]]
accu.append((STR, stringize(toks)))
j += 1
else:
accu.append((p2, v2))
elif p2 == OP and v2 == '##':
# token pasting, how can man invent such a complicated system?
if accu and j+1 < len(to_add):
# we have at least two tokens
t1 = accu[-1]
if to_add[j+1][0] == IDENT and to_add[j+1][1] in arg_table:
toks = args[arg_table[to_add[j+1][1]]]
if toks:
accu[-1] = paste_tokens(t1, toks[0]) #(IDENT, accu[-1][1] + toks[0][1])
accu.extend(toks[1:])
else:
# error, case "a##"
accu.append((p2, v2))
accu.extend(toks)
elif to_add[j+1][0] == IDENT and to_add[j+1][1] == '__VA_ARGS__':
# first collect the tokens
va_toks = []
st = len(macro_def[0])
pt = len(args)
for x in args[pt-st+1:]:
va_toks.extend(x)
va_toks.append((OP, ','))
if va_toks:
va_toks.pop() # extra comma
if len(accu)>1:
(p3, v3) = accu[-1]
(p4, v4) = accu[-2]
if v3 == '##':
# remove the token paste
accu.pop()
if v4 == ',' and pt < st:
# remove the comma
accu.pop()
accu += va_toks
else:
accu[-1] = paste_tokens(t1, to_add[j+1])
j += 1
else:
# Invalid paste, case "##a" or "b##"
accu.append((p2, v2))
elif p2 == IDENT and v2 in arg_table:
toks = args[arg_table[v2]]
reduce_tokens(toks, defs, ban+[v])
accu.extend(toks)
else:
accu.append((p2, v2))
j += 1
reduce_tokens(accu, defs, ban+[v])
for x in range(len(accu)-1, -1, -1):
lst.insert(i, accu[x])
i += 1
[docs]def eval_macro(lst, defs):
"""
Reduce the tokens by :py:func:`waflib.Tools.c_preproc.reduce_tokens` and try to return a 0/1 result by :py:func:`waflib.Tools.c_preproc.reduce_eval`.
:param lst: list of tokens
:type lst: list of tuple(token, value)
:param defs: macro definitions
:type defs: dict
:rtype: int
"""
reduce_tokens(lst, defs, [])
if not lst:
raise PreprocError('missing tokens to evaluate')
if lst:
p, v = lst[0]
if p == IDENT and v not in defs:
raise PreprocError('missing macro %r' % lst)
p, v = reduce_eval(lst)
return int(v) != 0
re_include = re.compile(r'^\s*(<(?:.*)>|"(?:.*)")')
[docs]def parse_char(txt):
"""
Parse a c character
:param txt: character to parse
:type txt: string
:return: a character literal
:rtype: string
"""
if not txt:
raise PreprocError('attempted to parse a null char')
if txt[0] != '\\':
return ord(txt)
c = txt[1]
if c == 'x':
if len(txt) == 4 and txt[3] in string.hexdigits:
return int(txt[2:], 16)
return int(txt[2:], 16)
elif c.isdigit():
if c == '0' and len(txt)==2:
return 0
for i in 3, 2, 1:
if len(txt) > i and txt[1:1+i].isdigit():
return (1+i, int(txt[1:1+i], 8))
else:
try:
return chr_esc[c]
except KeyError:
raise PreprocError('could not parse char literal %r' % txt)
[docs]def tokenize(s):
"""
Convert a string into a list of tokens (shlex.split does not apply to c/c++/d)
:param s: input to tokenize
:type s: string
:return: a list of tokens
:rtype: list of tuple(token, value)
"""
return tokenize_private(s)[:] # force a copy of the results
def tokenize_private(s):
ret = []
for match in re_clexer.finditer(s):
m = match.group
for name in tok_types:
v = m(name)
if v:
if name == IDENT:
if v in g_optrans:
name = OP
elif v.lower() == "true":
v = 1
name = NUM
elif v.lower() == "false":
v = 0
name = NUM
elif name == NUM:
if m('oct'):
v = int(v, 8)
elif m('hex'):
v = int(m('hex'), 16)
elif m('n0'):
v = m('n0')
else:
v = m('char')
if v:
v = parse_char(v)
else:
v = m('n2') or m('n4')
elif name == OP:
if v == '%:':
v = '#'
elif v == '%:%:':
v = '##'
elif name == STR:
# remove the quotes around the string
v = v[1:-1]
ret.append((name, v))
break
return ret
def format_defines(lst):
ret = []
for y in lst:
if y:
pos = y.find('=')
if pos == -1:
# "-DFOO" should give "#define FOO 1"
ret.append(y)
elif pos > 0:
# all others are assumed to be -DX=Y
ret.append('%s %s' % (y[:pos], y[pos+1:]))
else:
raise ValueError('Invalid define expression %r' % y)
return ret
[docs]class c_parser(object):
"""
Used by :py:func:`waflib.Tools.c_preproc.scan` to parse c/h files. Note that by default,
only project headers are parsed.
"""
def __init__(self, nodepaths=None, defines=None):
self.lines = []
"""list of lines read"""
if defines is None:
self.defs = {}
else:
self.defs = dict(defines) # make a copy
self.state = []
self.count_files = 0
self.currentnode_stack = []
self.nodepaths = nodepaths or []
"""Include paths"""
self.nodes = []
"""List of :py:class:`waflib.Node.Node` found so far"""
self.names = []
"""List of file names that could not be matched by any file"""
self.curfile = ''
"""Current file"""
self.ban_includes = set()
"""Includes that must not be read (#pragma once)"""
self.listed = set()
"""Include nodes/names already listed to avoid duplicates in self.nodes/self.names"""
[docs] def cached_find_resource(self, node, filename):
"""
Find a file from the input directory
:param node: directory
:type node: :py:class:`waflib.Node.Node`
:param filename: header to find
:type filename: string
:return: the node if found, or None
:rtype: :py:class:`waflib.Node.Node`
"""
try:
cache = node.ctx.preproc_cache_node
except AttributeError:
cache = node.ctx.preproc_cache_node = Utils.lru_cache(FILE_CACHE_SIZE)
key = (node, filename)
try:
return cache[key]
except KeyError:
ret = node.find_resource(filename)
if ret:
if getattr(ret, 'children', None):
ret = None
elif ret.is_child_of(node.ctx.bldnode):
tmp = node.ctx.srcnode.search_node(ret.path_from(node.ctx.bldnode))
if tmp and getattr(tmp, 'children', None):
ret = None
cache[key] = ret
return ret
[docs] def tryfind(self, filename, kind='"', env=None):
"""
Try to obtain a node from the filename based from the include paths. Will add
the node found to :py:attr:`waflib.Tools.c_preproc.c_parser.nodes` or the file name to
:py:attr:`waflib.Tools.c_preproc.c_parser.names` if no corresponding file is found. Called by
:py:attr:`waflib.Tools.c_preproc.c_parser.start`.
:param filename: header to find
:type filename: string
:return: the node if found
:rtype: :py:class:`waflib.Node.Node`
"""
if filename.endswith('.moc'):
# we could let the qt4 module use a subclass, but then the function "scan" below must be duplicated
# in the qt4 and in the qt5 classes. So we have two lines here and it is sufficient.
self.names.append(filename)
return None
self.curfile = filename
found = None
if kind == '"':
if env.MSVC_VERSION:
for n in reversed(self.currentnode_stack):
found = self.cached_find_resource(n, filename)
if found:
break
else:
found = self.cached_find_resource(self.currentnode_stack[-1], filename)
if not found:
for n in self.nodepaths:
found = self.cached_find_resource(n, filename)
if found:
break
listed = self.listed
if found and not found in self.ban_includes:
if found not in listed:
listed.add(found)
self.nodes.append(found)
self.addlines(found)
else:
if filename not in listed:
listed.add(filename)
self.names.append(filename)
return found
def parse_lines(self, node):
try:
cache = node.ctx.preproc_cache_lines
except AttributeError:
cache = node.ctx.preproc_cache_lines = Utils.lru_cache(LINE_CACHE_SIZE)
try:
return cache[node]
except KeyError:
cache[node] = lines = self.filter_comments(node)
lines.append((POPFILE, ''))
lines.reverse()
return lines
[docs] def addlines(self, node):
"""
Add the lines from a header in the list of preprocessor lines to parse
:param node: header
:type node: :py:class:`waflib.Node.Node`
"""
self.currentnode_stack.append(node.parent)
self.count_files += 1
if self.count_files > recursion_limit:
# issue #812
raise PreprocError('recursion limit exceeded')
if Logs.verbose:
Logs.debug('preproc: reading file %r', node)
try:
lines = self.parse_lines(node)
except EnvironmentError:
raise PreprocError('could not read the file %r' % node)
except Exception:
if Logs.verbose > 0:
Logs.error('parsing %r failed %s', node, traceback.format_exc())
else:
self.lines.extend(lines)
[docs] def start(self, node, env):
"""
Preprocess a source file to obtain the dependencies, which are accumulated to :py:attr:`waflib.Tools.c_preproc.c_parser.nodes`
and :py:attr:`waflib.Tools.c_preproc.c_parser.names`.
:param node: source file
:type node: :py:class:`waflib.Node.Node`
:param env: config set containing additional defines to take into account
:type env: :py:class:`waflib.ConfigSet.ConfigSet`
"""
Logs.debug('preproc: scanning %s (in %s)', node.name, node.parent.name)
self.current_file = node
self.addlines(node)
# macros may be defined on the command-line, so they must be parsed as if they were part of the file
if env.DEFINES:
lst = format_defines(env.DEFINES)
lst.reverse()
self.lines.extend([('define', x) for x in lst])
while self.lines:
(token, line) = self.lines.pop()
if token == POPFILE:
self.count_files -= 1
self.currentnode_stack.pop()
continue
try:
state = self.state
# make certain we define the state if we are about to enter in an if block
if token[:2] == 'if':
state.append(undefined)
elif token == 'endif':
state.pop()
# skip lines when in a dead 'if' branch, wait for the endif
if token[0] != 'e':
if skipped in self.state or ignored in self.state:
continue
if token == 'if':
ret = eval_macro(tokenize(line), self.defs)
if ret:
state[-1] = accepted
else:
state[-1] = ignored
elif token == 'ifdef':
m = re_mac.match(line)
if m and m.group() in self.defs:
state[-1] = accepted
else:
state[-1] = ignored
elif token == 'ifndef':
m = re_mac.match(line)
if m and m.group() in self.defs:
state[-1] = ignored
else:
state[-1] = accepted
elif token == 'include' or token == 'import':
(kind, inc) = extract_include(line, self.defs)
self.current_file = self.tryfind(inc, kind, env)
if token == 'import':
self.ban_includes.add(self.current_file)
elif token == 'elif':
if state[-1] == accepted:
state[-1] = skipped
elif state[-1] == ignored:
if eval_macro(tokenize(line), self.defs):
state[-1] = accepted
elif token == 'else':
if state[-1] == accepted:
state[-1] = skipped
elif state[-1] == ignored:
state[-1] = accepted
elif token == 'define':
try:
self.defs[self.define_name(line)] = line
except AttributeError:
raise PreprocError('Invalid define line %r' % line)
elif token == 'undef':
m = re_mac.match(line)
if m and m.group() in self.defs:
self.defs.__delitem__(m.group())
#print "undef %s" % name
elif token == 'pragma':
if re_pragma_once.match(line.lower()):
self.ban_includes.add(self.current_file)
except Exception as e:
if Logs.verbose:
Logs.debug('preproc: line parsing failed (%s): %s %s', e, line, traceback.format_exc())
[docs] def define_name(self, line):
"""
:param line: define line
:type line: string
:rtype: string
:return: the define name
"""
return re_mac.match(line).group()
[docs]def scan(task):
"""
Get the dependencies using a c/c++ preprocessor, this is required for finding dependencies of the kind::
#include some_macro()
This function is bound as a task method on :py:class:`waflib.Tools.c.c` and :py:class:`waflib.Tools.cxx.cxx` for example
"""
try:
incn = task.generator.includes_nodes
except AttributeError:
raise Errors.WafError('%r is missing a feature such as "c", "cxx" or "includes": ' % task.generator)
if go_absolute:
nodepaths = incn + [task.generator.bld.root.find_dir(x) for x in standard_includes]
else:
nodepaths = [x for x in incn if x.is_child_of(x.ctx.srcnode) or x.is_child_of(x.ctx.bldnode)]
tmp = c_parser(nodepaths)
tmp.start(task.inputs[0], task.env)
return (tmp.nodes, tmp.names)
