gfx/angle/src/compiler/preprocessor/numeric_lex.h

Wed, 31 Dec 2014 06:09:35 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 06:09:35 +0100
changeset 0
6474c204b198
permissions
-rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

michael@0 1 //
michael@0 2 // Copyright (c) 2012 The ANGLE Project Authors. All rights reserved.
michael@0 3 // Use of this source code is governed by a BSD-style license that can be
michael@0 4 // found in the LICENSE file.
michael@0 5 //
michael@0 6
michael@0 7 // numeric_lex.h: Functions to extract numeric values from string.
michael@0 8
michael@0 9 #ifndef COMPILER_PREPROCESSOR_NUMERIC_LEX_H_
michael@0 10 #define COMPILER_PREPROCESSOR_NUMERIC_LEX_H_
michael@0 11
michael@0 12 #include <sstream>
michael@0 13
michael@0 14 namespace pp {
michael@0 15
michael@0 16 inline std::ios::fmtflags numeric_base_int(const std::string& str)
michael@0 17 {
michael@0 18 if ((str.size() >= 2) &&
michael@0 19 (str[0] == '0') &&
michael@0 20 (str[1] == 'x' || str[1] == 'X'))
michael@0 21 {
michael@0 22 return std::ios::hex;
michael@0 23 }
michael@0 24 else if ((str.size() >= 1) && (str[0] == '0'))
michael@0 25 {
michael@0 26 return std::ios::oct;
michael@0 27 }
michael@0 28 return std::ios::dec;
michael@0 29 }
michael@0 30
michael@0 31 // The following functions parse the given string to extract a numerical
michael@0 32 // value of the given type. These functions assume that the string is
michael@0 33 // of the correct form. They can only fail if the parsed value is too big,
michael@0 34 // in which case false is returned.
michael@0 35
michael@0 36 template<typename IntType>
michael@0 37 bool numeric_lex_int(const std::string& str, IntType* value)
michael@0 38 {
michael@0 39 std::istringstream stream(str);
michael@0 40 // This should not be necessary, but MSVS has a buggy implementation.
michael@0 41 // It returns incorrect results if the base is not specified.
michael@0 42 stream.setf(numeric_base_int(str), std::ios::basefield);
michael@0 43
michael@0 44 stream >> (*value);
michael@0 45 return !stream.fail();
michael@0 46 }
michael@0 47
michael@0 48 template<typename FloatType>
michael@0 49 bool numeric_lex_float(const std::string& str, FloatType* value)
michael@0 50 {
michael@0 51 std::istringstream stream(str);
michael@0 52 // Force "C" locale so that decimal character is always '.', and
michael@0 53 // not dependent on the current locale.
michael@0 54 stream.imbue(std::locale::classic());
michael@0 55
michael@0 56 stream >> (*value);
michael@0 57 return !stream.fail();
michael@0 58 }
michael@0 59
michael@0 60 } // namespace pp.
michael@0 61 #endif // COMPILER_PREPROCESSOR_NUMERIC_LEX_H_

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