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Diffstat (limited to 'ext/googlemock/scripts/generator/cpp/tokenize.py')
-rwxr-xr-x | ext/googlemock/scripts/generator/cpp/tokenize.py | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/ext/googlemock/scripts/generator/cpp/tokenize.py b/ext/googlemock/scripts/generator/cpp/tokenize.py new file mode 100755 index 000000000..359d5562d --- /dev/null +++ b/ext/googlemock/scripts/generator/cpp/tokenize.py @@ -0,0 +1,287 @@ +#!/usr/bin/env python +# +# Copyright 2007 Neal Norwitz +# Portions Copyright 2007 Google Inc. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +"""Tokenize C++ source code.""" + +__author__ = 'nnorwitz@google.com (Neal Norwitz)' + + +try: + # Python 3.x + import builtins +except ImportError: + # Python 2.x + import __builtin__ as builtins + + +import sys + +from cpp import utils + + +if not hasattr(builtins, 'set'): + # Nominal support for Python 2.3. + from sets import Set as set + + +# Add $ as a valid identifier char since so much code uses it. +_letters = 'abcdefghijklmnopqrstuvwxyz' +VALID_IDENTIFIER_CHARS = set(_letters + _letters.upper() + '_0123456789$') +HEX_DIGITS = set('0123456789abcdefABCDEF') +INT_OR_FLOAT_DIGITS = set('01234567890eE-+') + + +# C++0x string preffixes. +_STR_PREFIXES = set(('R', 'u8', 'u8R', 'u', 'uR', 'U', 'UR', 'L', 'LR')) + + +# Token types. +UNKNOWN = 'UNKNOWN' +SYNTAX = 'SYNTAX' +CONSTANT = 'CONSTANT' +NAME = 'NAME' +PREPROCESSOR = 'PREPROCESSOR' + +# Where the token originated from. This can be used for backtracking. +# It is always set to WHENCE_STREAM in this code. +WHENCE_STREAM, WHENCE_QUEUE = range(2) + + +class Token(object): + """Data container to represent a C++ token. + + Tokens can be identifiers, syntax char(s), constants, or + pre-processor directives. + + start contains the index of the first char of the token in the source + end contains the index of the last char of the token in the source + """ + + def __init__(self, token_type, name, start, end): + self.token_type = token_type + self.name = name + self.start = start + self.end = end + self.whence = WHENCE_STREAM + + def __str__(self): + if not utils.DEBUG: + return 'Token(%r)' % self.name + return 'Token(%r, %s, %s)' % (self.name, self.start, self.end) + + __repr__ = __str__ + + +def _GetString(source, start, i): + i = source.find('"', i+1) + while source[i-1] == '\\': + # Count the trailing backslashes. + backslash_count = 1 + j = i - 2 + while source[j] == '\\': + backslash_count += 1 + j -= 1 + # When trailing backslashes are even, they escape each other. + if (backslash_count % 2) == 0: + break + i = source.find('"', i+1) + return i + 1 + + +def _GetChar(source, start, i): + # NOTE(nnorwitz): may not be quite correct, should be good enough. + i = source.find("'", i+1) + while source[i-1] == '\\': + # Need to special case '\\'. + if (i - 2) > start and source[i-2] == '\\': + break + i = source.find("'", i+1) + # Try to handle unterminated single quotes (in a #if 0 block). + if i < 0: + i = start + return i + 1 + + +def GetTokens(source): + """Returns a sequence of Tokens. + + Args: + source: string of C++ source code. + + Yields: + Token that represents the next token in the source. + """ + # Cache various valid character sets for speed. + valid_identifier_chars = VALID_IDENTIFIER_CHARS + hex_digits = HEX_DIGITS + int_or_float_digits = INT_OR_FLOAT_DIGITS + int_or_float_digits2 = int_or_float_digits | set('.') + + # Only ignore errors while in a #if 0 block. + ignore_errors = False + count_ifs = 0 + + i = 0 + end = len(source) + while i < end: + # Skip whitespace. + while i < end and source[i].isspace(): + i += 1 + if i >= end: + return + + token_type = UNKNOWN + start = i + c = source[i] + if c.isalpha() or c == '_': # Find a string token. + token_type = NAME + while source[i] in valid_identifier_chars: + i += 1 + # String and character constants can look like a name if + # they are something like L"". + if (source[i] == "'" and (i - start) == 1 and + source[start:i] in 'uUL'): + # u, U, and L are valid C++0x character preffixes. + token_type = CONSTANT + i = _GetChar(source, start, i) + elif source[i] == "'" and source[start:i] in _STR_PREFIXES: + token_type = CONSTANT + i = _GetString(source, start, i) + elif c == '/' and source[i+1] == '/': # Find // comments. + i = source.find('\n', i) + if i == -1: # Handle EOF. + i = end + continue + elif c == '/' and source[i+1] == '*': # Find /* comments. */ + i = source.find('*/', i) + 2 + continue + elif c in ':+-<>&|*=': # : or :: (plus other chars). + token_type = SYNTAX + i += 1 + new_ch = source[i] + if new_ch == c and c != '>': # Treat ">>" as two tokens. + i += 1 + elif c == '-' and new_ch == '>': + i += 1 + elif new_ch == '=': + i += 1 + elif c in '()[]{}~!?^%;/.,': # Handle single char tokens. + token_type = SYNTAX + i += 1 + if c == '.' and source[i].isdigit(): + token_type = CONSTANT + i += 1 + while source[i] in int_or_float_digits: + i += 1 + # Handle float suffixes. + for suffix in ('l', 'f'): + if suffix == source[i:i+1].lower(): + i += 1 + break + elif c.isdigit(): # Find integer. + token_type = CONSTANT + if c == '0' and source[i+1] in 'xX': + # Handle hex digits. + i += 2 + while source[i] in hex_digits: + i += 1 + else: + while source[i] in int_or_float_digits2: + i += 1 + # Handle integer (and float) suffixes. + for suffix in ('ull', 'll', 'ul', 'l', 'f', 'u'): + size = len(suffix) + if suffix == source[i:i+size].lower(): + i += size + break + elif c == '"': # Find string. + token_type = CONSTANT + i = _GetString(source, start, i) + elif c == "'": # Find char. + token_type = CONSTANT + i = _GetChar(source, start, i) + elif c == '#': # Find pre-processor command. + token_type = PREPROCESSOR + got_if = source[i:i+3] == '#if' and source[i+3:i+4].isspace() + if got_if: + count_ifs += 1 + elif source[i:i+6] == '#endif': + count_ifs -= 1 + if count_ifs == 0: + ignore_errors = False + + # TODO(nnorwitz): handle preprocessor statements (\ continuations). + while 1: + i1 = source.find('\n', i) + i2 = source.find('//', i) + i3 = source.find('/*', i) + i4 = source.find('"', i) + # NOTE(nnorwitz): doesn't handle comments in #define macros. + # Get the first important symbol (newline, comment, EOF/end). + i = min([x for x in (i1, i2, i3, i4, end) if x != -1]) + + # Handle #include "dir//foo.h" properly. + if source[i] == '"': + i = source.find('"', i+1) + 1 + assert i > 0 + continue + # Keep going if end of the line and the line ends with \. + if not (i == i1 and source[i-1] == '\\'): + if got_if: + condition = source[start+4:i].lstrip() + if (condition.startswith('0') or + condition.startswith('(0)')): + ignore_errors = True + break + i += 1 + elif c == '\\': # Handle \ in code. + # This is different from the pre-processor \ handling. + i += 1 + continue + elif ignore_errors: + # The tokenizer seems to be in pretty good shape. This + # raise is conditionally disabled so that bogus code + # in an #if 0 block can be handled. Since we will ignore + # it anyways, this is probably fine. So disable the + # exception and return the bogus char. + i += 1 + else: + sys.stderr.write('Got invalid token in %s @ %d token:%s: %r\n' % + ('?', i, c, source[i-10:i+10])) + raise RuntimeError('unexpected token') + + if i <= 0: + print('Invalid index, exiting now.') + return + yield Token(token_type, source[start:i], start, i) + + +if __name__ == '__main__': + def main(argv): + """Driver mostly for testing purposes.""" + for filename in argv[1:]: + source = utils.ReadFile(filename) + if source is None: + continue + + for token in GetTokens(source): + print('%-12s: %s' % (token.token_type, token.name)) + # print('\r%6.2f%%' % (100.0 * index / token.end),) + sys.stdout.write('\n') + + + main(sys.argv) |