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https://github.com/Sei-Lisa/LSL-PyOptimizer
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689 lines
26 KiB
Python
689 lines
26 KiB
Python
# (C) Copyright 2015-2019 Sei Lisa. All rights reserved.
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#
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# This file is part of LSL PyOptimizer.
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#
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# LSL PyOptimizer is free software: you can redistribute it and/or
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# modify it under the terms of the GNU General Public License as
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# published by the Free Software Foundation, either version 3 of the
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# License, or (at your option) any later version.
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#
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# LSL PyOptimizer is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with LSL PyOptimizer. If not, see <http://www.gnu.org/licenses/>.
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#
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# This file includes an excerpt from PCPP, by Niall Douglas and David
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# Beazley. PCPP is available here: https://github.com/ned14/pcpp and
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# distributed under the following conditions:
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#
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# (C) Copyright 2018-2019 Niall Douglas http://www.nedproductions.biz/
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# (C) Copyright 2007-2019 David Beazley http://www.dabeaz.com/
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#
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions are
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# met:
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#
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# * Redistributions of source code must retain the above copyright notice,
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# this list of conditions and the following disclaimer.
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# * Redistributions in binary form must reproduce the above copyright notice,
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# this list of conditions and the following disclaimer in the documentation
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# and/or other materials provided with the distribution.
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# * Neither the name of the David Beazley or Dabeaz LLC may be used to
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# endorse or promote products derived from this software without
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# specific prior written permission.
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#
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#
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# (End of terms and conditions for the PCPP excerpt)
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#
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# The particular excerpt used is this one:
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# https://github.com/ned14/pcpp/blob/e1219ce157b4dfcfee3181faa6ec5129c3a41e78/pcpp/preprocessor.py#L873-L935
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#
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# The following fragments of code are hereby irrevokably donated to the
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# public domain:
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# - The Evaluator class in its entirety.
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# - The evalexpr method in its entirety except for the excerpt mentioned
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# above, which remains copyright of its authors.
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# - Every line between this one and the Evaluator class.
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import sys, os, re, copy
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oldsyspath = sys.path
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sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)),
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'pcpp'))
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from pcpp import preprocessor
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path = oldsyspath
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# Define the number of bits to work with in expression evaluation
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# (per the standard, this should be the bits in uintmax_t).
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INTMAXBITS = 64
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UINTMAX_MAX = (1 << INTMAXBITS) - 1
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INTMAX_MIN = -(1 << (INTMAXBITS - 1))
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DSYMBOLS = {'->', '-=', '--', '==', '<<', '<=', '>>', '>=', '||', '|=',
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'&&', '&=', '!=', '^=', '*=', '/=', '%=', '+=', '++'}
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DIGRAPHS = {'<:':'[', ':>':']', '<%':'{', '%>':'}', '%:':'#'}
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ESCAPES = {'a':7,'b':8,'f':12,'n':10,'r':13,'t':9,'v':11,
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'"':34, '\\':92, '\'':39, '?':63}
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# Exception to report an evaluation error
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class EvalError(Exception): pass
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class uint(long): pass
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class sint(long): pass
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class Evaluator(object):
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"""Recursive descendent parser to evaluate C preprocessor expressions."""
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# Int parser
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resolve_int_regex = re.compile(
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# Group 1: Hex
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# Group 2: Oct
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# Group 3: Dec
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# Group 4: Unsigned
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r'^(?:(0x[0-9a-f]+)|(0[0-7]*)|([1-9][0-9]*))'
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r'(?:(u(?:ll?)?|(?:ll?)?u)|(?:ll?)?)$', re.I | re.S)
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# Char parser (without the quotes)
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ctoken_regex = re.compile(
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r'\\(?:'
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r'[\?' r"'" r'"\\abfnrtv]|[Xx][0-9a-fA-F]+|[0-7]{1,3}'
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r'|u[0-9a-fA-F]{4}|U[0-9a-fA-F]{8}'
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r')'
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r'|.', re.S)
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def __init__(self, tokens):
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assert tokens, "Empty tokens list???"
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self.tokens = tokens
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self.ptr = 0
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self.evaluating = True
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self.conv = {uint: self.to_uint, sint: self.to_sint}
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self.nextToken()
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def to_uint(self, i):
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return uint(i & UINTMAX_MAX)
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def to_sint(self, i):
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return sint(((i - INTMAX_MIN) & UINTMAX_MAX) + INTMAX_MIN)
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def nextToken(self):
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"""Sets self.token to the next token and advances the token pointer.
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Skips whitespace tokens. Returns a CPP_WS token with value '\n' if
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there's no next token. Returns synthesized tokens for multichar tokens
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not currently handled by PCPP.
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"""
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try:
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while True:
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tok = self.token = self.tokens[self.ptr]
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self.ptr += 1
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# Eat whitespace except newlines, and /* */ comments
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if (tok.type == 'CPP_WS' and '\n' not in tok.value
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or tok.type == 'CPP_COMMENT1'
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):
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continue
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break
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except IndexError:
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# Synthesize a new CPP_WS token with a newline, to signal
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# end-of-text (we copy it from the last one in the token stream).
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tok = self.token = copy.copy(self.tokens[-1])
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tok.type = 'CPP_WS'
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tok.value = '\n'
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return
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# Single-line comments are line terminators; convert them
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if tok.type == 'CPP_COMMENT2':
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tok = self.token = copy.copy(tok)
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tok.type = 'CPP_WS'
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tok.value = '\n'
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return
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# Work around a lexing problem in PCPP
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#
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# PCPP doesn't tokenize multichar tokens except ##, so we do that job
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# here, to ease processing and report more errors (e.g. 5--3 should be
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# reported as an error because it uses the post-decrement operator,
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# instead of evaluating to 8, which is the correct result for 5- -3).
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# The tokens processed here are those in the C standard missed by PCPP:
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# -> -= -- << <= >> >= || |= && &= == != ^= *= /= += ++ %=
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# >>= <<=
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# ...
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# <: :> <% %> %:
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# %:%:
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#
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# This is already a single token, therefore it's not processed here:
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# ##
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try:
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next = self.tokens[self.ptr]
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except IndexError:
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return
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s = tok.type + next.type
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if s in DSYMBOLS:
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tok = self.token = copy.copy(tok)
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tok.type = s
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tok.value += next.value
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self.ptr += 1
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if s in ('<<', '>>'):
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# check for <<= >>=
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try:
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next2 = self.tokens[self.ptr]
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if next2.type == '=':
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tok.type += next2.type
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tok.value += next2.value
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self.ptr += 1
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except IndexError:
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pass
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return
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if s in DIGRAPHS:
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# digraph or DPOUND
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tok = self.token = copy.copy(tok)
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tok.type = DIGRAPHS[s]
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tok.value += next.value
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self.ptr += 1
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try:
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next2 = self.tokens[self.ptr]
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next3 = self.tokens[self.ptr + 1]
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if next2.type == '%' and next3.type == ':':
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tok.type = '##'
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tok.value += next2.value + next3.value
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self.ptr += 2
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except IndexError:
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pass
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return
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if s == '..':
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try:
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next2 = self.tokens[self.ptr + 1]
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if next2.type == '.':
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tok = self.token = copy.copy(tok)
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tok.type = '...'
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tok.value += next.value + next2.value
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self.ptr += 2
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except IndexError:
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pass
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return
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def eat(self, *toktypes):
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"""Return True and advance pointer if the current token matches. """
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if self.token.type in toktypes:
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self.nextToken()
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return True
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return False
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def expect(self, toktype):
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"""Checks an expected token and eats it"""
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expect = toktype
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if toktype == 'END' and '\n' in self.token.value:
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expect = 'CPP_WS'
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if not self.eat(expect):
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raise EvalError(
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"Unexpected token %s (%s) in expression, expected %s"
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% (repr(self.token.value), self.token.type, toktype))
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def conversions(self, op1, op2):
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"""Perform usual arithmetic conversions on two operands."""
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assert type(op1) in (sint, uint) and type(op2) in (sint, uint)
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if type(op1) != type(op2):
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return self.to_uint(op1), self.to_uint(op2)
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return op1, op2
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def primary_expression(self, evaluating):
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"""Non-terminal: primary_expression.
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primary_expression:
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IDENTIFIER | STRING_LITERAL | CHAR_LITERAL | INTEGER
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| '(' expression ')'
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"""
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tok = self.token
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if self.eat('('):
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ret = self.expression(evaluating)
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self.expect(')')
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return ret
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#if self.eat('CPP_STRING'):
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# return tok.value
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if self.eat('CPP_CHAR'):
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charstr = tok.value
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unicode = False
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if tok.value.startswith('L'):
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unicode = True
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charstr = charstr[2:-1]
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else:
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charstr = charstr[1:-1]
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onechar = False
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for ctok in self.ctoken_regex.finditer(charstr):
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if onechar:
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raise EvalError("Multiple characters in char literal")
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onechar = True
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c = ctok.group(0)
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if c == '\\':
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raise EvalError("Invalid escape sequence in char literal")
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if c.startswith('\\'):
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if c.startswith('\\u') or c.startswith('\\U'):
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result = int(c[2:], 16)
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if ((result < 0xA0 and result not in (0x24,0x40,0x60))
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or 0xD800 <= result <= 0xDFFF
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):
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raise EvalError("Invalid universal character %s"
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% c)
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if result > 0xFF and not unicode:
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raise EvalError("Char literal out of range")
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elif c.startswith('\\x') or c.startswith('\\X'):
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result = int(c[2:], 16)
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if result > 0xFF:
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raise EvalError("Hex literal out of range")
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elif c[1] in ESCAPES:
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result = ESCAPES[c[1]]
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else:
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result = int(c[1:], 8)
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else:
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assert len(c) == 1 and c != '\''
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return ord(c)
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# This may need reconsideration if INTMAXBITS is < 22 (the bits
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# necessary to fit a Unicode codepoint in a signed integer).
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return sint(result) # our char is unsigned
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if tok.type == 'CPP_ID':
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tok = self.token = copy.copy(tok)
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tok.type = 'CPP_INTEGER'
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tok.value = '0'
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# fall through to process it as CPP_INTEGER
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if self.eat('CPP_INTEGER'):
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m = self.resolve_int_regex.search(tok.value)
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if not m:
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raise EvalError("Invalid integer literal")
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val = (int(m.group(2), 8) if m.group(2)
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else int(m.group(1) or m.group(3), 0))
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val = self.to_uint(val) if m.group(4) else self.to_sint(val)
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return val
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if tok.type == 'CPP_STRING':
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raise EvalError("Strings are not allowed in expressions")
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if tok.type == 'CPP_WS' and '\n' in tok.value:
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raise EvalError('Unexpected end of expression')
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self.expect('CPP_INTEGER')
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def factor_expression(self, evaluating):
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"""Non-terminal: factor_expression
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factor_expression:
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primary_expression
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| unary_operator factor_expression
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"""
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# Avoid recursing for unary operators. Apply them post-evaluation.
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k = None
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while True:
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toktype = self.token.type
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if self.eat('-', '+', '~', '!') and toktype != '+':
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k = k or []
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k.append(toktype)
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else:
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break
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result = self.primary_expression(evaluating)
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while k:
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operation = k.pop()
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if operation == '!':
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result = sint(0 if result else 1)
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else:
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result = self.conv[type(result)](-result if operation == '-'
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else ~result)
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return result
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def term_expression(self, evaluating):
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"""Non-terminal: term_expression
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term_expression:
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factor_expression
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| term_expression '*' factor_expression
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| term_expression '/' factor_expression
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| term_expression '%' factor_expression
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"""
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result = self.factor_expression(evaluating)
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while True:
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toktype = self.token.type
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if not self.eat('*', '/', '%'):
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return result
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operand = self.factor_expression(evaluating)
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if evaluating and operand == 0 and toktype != '*':
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raise EvalError("Division by zero")
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result, operand = self.conversions(result, operand)
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result = self.conv[type(result)](result if not evaluating
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else result * operand if toktype == '*'
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else result // operand if toktype == '/'
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else result % operand)
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def arithmetic_expression(self, evaluating):
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"""Non-terminal: arithmetic_expression
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arithmetic_expression:
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term_expression
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| arithmetic_expression '+' term_expression
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| arithmetic_expression '-' term_expression
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"""
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result = self.term_expression(evaluating)
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while True:
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toktype = self.token.type
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if not self.eat('+', '-'):
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return result
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operand = self.term_expression(evaluating)
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result, operand = self.conversions(result, operand)
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result = self.conv[type(result)](result + operand if toktype == '+'
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else result - operand)
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def shift_expression(self, evaluating):
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"""Non-terminal: shift_expression
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shift_expression:
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arithmetic_expression
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| shift_expression '<<' arithmetic_expression
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| shift_expression '>>' arithmetic_expression
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"""
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result = self.arithmetic_expression(evaluating)
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while True:
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tok = self.token
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if not self.eat('<<', '>>'):
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return result
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operand = self.arithmetic_expression(evaluating)
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# We don't want a too large intermediate result, to prevent DoS
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result = self.conv[type(result)](result << min(operand, INTMAXBITS)
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if tok.type == '<<' else result >> max(operand, 0))
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def relational_expression(self, evaluating):
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"""Non-terminal: relational_expression
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relational_expression:
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shift_expression
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| relational_expression '>' shift_expression
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| relational_expression '<' shift_expression
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| relational_expression '>=' shift_expression
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| relational_expression '<=' shift_expression
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"""
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result = self.shift_expression(evaluating)
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while True:
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tok = self.token
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if not self.eat('<', '>', '<=', '>='):
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return result
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operand = self.shift_expression(evaluating)
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result, operand = self.conversions(result, operand)
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# Use the fact that a < b <-> b > a
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# Use the fact that a < b <-> !(a >= b)
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if tok.type == '>' or tok.type == '<=':
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result, operand = operand, result
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result = sint(1 if (result < operand) == (tok.type in ('<', '>'))
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else 0)
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def equality_expression(self, evaluating):
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"""Non-terminal: equality_expression
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equality_expression:
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relational_expression
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| equality_expression '==' relational_expression
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| equality_expression '!=' relational_expression
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"""
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result = self.relational_expression(evaluating)
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while True:
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tok = self.token
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if not self.eat('==', '!='):
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return result
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operand = self.relational_expression(evaluating)
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result, operand = self.conversions(result, operand)
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result = sint(1 if (result == operand) == (tok.type == '==')
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else 0)
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def bitwise_and_expression(self, evaluating):
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"""Non-terminal: bitwise_and_expression
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bitwise_and_expression:
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equality_expression
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| bitwise_and_expression '&' equality_expression
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"""
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result = self.equality_expression(evaluating)
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while True:
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if not self.eat('&'):
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return result
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operand = self.equality_expression(evaluating)
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result, operand = self.conversions(result, operand)
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result = self.conv[type(result)](result & operand)
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def bitwise_xor_expression(self, evaluating):
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"""Non-terminal: bitwise_xor_expression
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bitwise_xor_expression:
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bitwise_and_expression
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| bitwise_xor_expression '^' bitwise_and_expression
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"""
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result = self.bitwise_and_expression(evaluating)
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while True:
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if not self.eat('^'):
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return result
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operand = self.bitwise_and_expression(evaluating)
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result, operand = self.conversions(result, operand)
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result = self.conv[type(result)](result ^ operand)
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def bitwise_or_expression(self, evaluating):
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"""Non-terminal: bitwise_or_expression
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bitwise_or_expression:
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bitwise_xor_expression
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| bitwise_or_expression '|' bitwise_xor_expression
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"""
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result = self.bitwise_xor_expression(evaluating)
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while True:
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if not self.eat('|'):
|
|
return result
|
|
operand = self.bitwise_xor_expression(evaluating)
|
|
result, operand = self.conversions(result, operand)
|
|
result = self.conv[type(result)](result | operand)
|
|
|
|
def logical_and_expression(self, evaluating):
|
|
"""Non-terminal: logical_and_expression
|
|
|
|
logical_and_expression:
|
|
bitwise_or_expression
|
|
| logical_and_expression '&&' bitwise_or_expression
|
|
"""
|
|
result = self.bitwise_or_expression(evaluating)
|
|
while True:
|
|
if not self.eat('&&'):
|
|
return result
|
|
evaluating = evaluating and not not result
|
|
operand = self.bitwise_or_expression(evaluating)
|
|
result = sint(1 if result and (not evaluating or operand) else 0)
|
|
|
|
def logical_or_expression(self, evaluating):
|
|
"""Non-terminal: logical_or_expression
|
|
|
|
logical_or_expression:
|
|
logical_and_expression
|
|
| logical_or_expression '||' logical_and_expression
|
|
"""
|
|
result = self.logical_and_expression(evaluating)
|
|
while True:
|
|
if not self.eat('||'):
|
|
return result
|
|
evaluating = evaluating and not result
|
|
operand = self.logical_and_expression(evaluating)
|
|
result = sint(1 if result or (evaluating and operand) else 0)
|
|
|
|
def conditional_expression(self, evaluating):
|
|
"""Non-terminal: conditional_expression.
|
|
|
|
conditional_expression:
|
|
logical_or_expression
|
|
| logical_or_expression '?' expression ':' conditional_expression
|
|
"""
|
|
result = self.logical_or_expression(evaluating)
|
|
if self.eat('?'):
|
|
if result:
|
|
result = self.expression(evaluating)
|
|
self.expect(':')
|
|
operand = self.conditional_expression(False)
|
|
else:
|
|
operand = self.expression(False)
|
|
self.expect(':')
|
|
result = self.conditional_expression(evaluating)
|
|
result, operand = self.conversions(result, operand)
|
|
return result
|
|
|
|
def expression(self, evaluating = True):
|
|
"""Non-terminal: expression.
|
|
|
|
expression:
|
|
conditional_expression (always)
|
|
| expression conditional_expression (if not evaluating)
|
|
"""
|
|
if evaluating:
|
|
return self.conditional_expression(evaluating)
|
|
while True:
|
|
result = self.conditional_expression(evaluating)
|
|
if not self.eat(','):
|
|
return result
|
|
|
|
def evaluate(self):
|
|
result = self.expression(True)
|
|
|
|
# Did we eat all tokens?
|
|
self.expect('END')
|
|
return result
|
|
|
|
class Preproc(preprocessor.Preprocessor):
|
|
def __init__(self, input, defines=(), sysincpaths=(), incpaths=()):
|
|
super(Preproc, self).__init__()
|
|
self.auto_pragma_once_enabled = False
|
|
for define in defines:
|
|
self.define('%s %s' % define)
|
|
|
|
for v in sysincpaths:
|
|
self.add_path(v)
|
|
for v in incpaths:
|
|
self.add_path(v)
|
|
|
|
self.ignore = set()
|
|
self.parser = self.parsegen(input, '<stdin>', '<stdin>')
|
|
|
|
def get(self):
|
|
try:
|
|
import StringIO
|
|
except ImportError:
|
|
import io as StringIO
|
|
ret = StringIO.StringIO()
|
|
self.write(ret)
|
|
return (ret.getvalue(), self.macros)
|
|
|
|
def on_include_not_found(self, is_system_include, curdir, includepath):
|
|
"""Don't pass through the #include line if the file does not exist"""
|
|
self.on_error(self.lastdirective.source, self.lastdirective.lineno,
|
|
"Include file not found: %s" % includepath)
|
|
|
|
def evalexpr(self, tokens):
|
|
"""Evaluate a sequence of tokens as an expression.
|
|
|
|
The original uses eval(), which is unsafe for web usage. This one uses
|
|
our own recursive-descendent parser.
|
|
"""
|
|
|
|
# ****************************************************
|
|
# Start of fragment copied from PCPP's preprocessor.py
|
|
"""Evaluate an expression token sequence for the purposes of evaluating
|
|
integral expressions."""
|
|
if not tokens:
|
|
self.on_error('unknown', 0, "Empty expression")
|
|
return (0, None)
|
|
# tokens = tokenize(line)
|
|
# Search for defined macros
|
|
evalfuncts = {'defined' : lambda x: True}
|
|
evalvars = {}
|
|
def replace_defined(tokens):
|
|
i = 0
|
|
while i < len(tokens):
|
|
if tokens[i].type == self.t_ID and tokens[i].value == 'defined':
|
|
j = i + 1
|
|
needparen = False
|
|
result = "0L"
|
|
while j < len(tokens):
|
|
if tokens[j].type in self.t_WS:
|
|
j += 1
|
|
continue
|
|
elif tokens[j].type == self.t_ID:
|
|
if tokens[j].value in self.macros:
|
|
result = "1L"
|
|
else:
|
|
repl = self.on_unknown_macro_in_defined_expr(tokens[j])
|
|
if repl is None:
|
|
# Add this identifier to a dictionary of variables
|
|
evalvars[tokens[j].value] = 0
|
|
result = 'defined('+tokens[j].value+')'
|
|
else:
|
|
result = "1L" if repl else "0L"
|
|
if not needparen: break
|
|
elif tokens[j].value == '(':
|
|
needparen = True
|
|
elif tokens[j].value == ')':
|
|
break
|
|
else:
|
|
self.on_error(tokens[i].source,tokens[i].lineno,"Malformed defined()")
|
|
j += 1
|
|
if result.startswith('defined'):
|
|
tokens[i].type = self.t_ID
|
|
tokens[i].value = result
|
|
else:
|
|
tokens[i].type = self.t_INTEGER
|
|
tokens[i].value = self.t_INTEGER_TYPE(result)
|
|
del tokens[i+1:j+1]
|
|
i += 1
|
|
return tokens
|
|
# Replace any defined(macro) before macro expansion
|
|
tokens = replace_defined(tokens)
|
|
tokens = self.expand_macros(tokens)
|
|
# Replace any defined(macro) after macro expansion
|
|
tokens = replace_defined(tokens)
|
|
if not tokens:
|
|
return (0, None)
|
|
for i,t in enumerate(tokens):
|
|
if t.type == self.t_ID:
|
|
repl = self.on_unknown_macro_in_expr(copy.copy(t))
|
|
if repl is None:
|
|
# Add this identifier to a dictionary of variables
|
|
evalvars[t.value] = 0
|
|
else:
|
|
tokens[i] = t = repl
|
|
# End of fragment copied from PCPP's preprocessor.py
|
|
# **************************************************
|
|
|
|
del evalfuncts # we don't use this
|
|
|
|
evaluator = Evaluator(tokens)
|
|
try:
|
|
result = int(evaluator.evaluate())
|
|
except EvalError as e:
|
|
self.on_error(evaluator.token.source, evaluator.token.lineno,
|
|
e.message)
|
|
return (0, None)
|
|
del evaluator
|
|
|
|
return (result, tokens) if evalvars else (result, None)
|