1/*-
2 * Copyright (c) 2013 David Chisnall
3 * All rights reserved.
4 *
5 * This software was developed by SRI International and the University of
6 * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
7 * ("CTSRD"), as part of the DARPA CRASH research programme.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD$
31 */
32
33#ifndef _UTIL_HH_
34#define _UTIL_HH_
35
36#include <vector>
37
38// If we aren't using C++11, then just ignore static asserts.
39#if __cplusplus < 201103L
40#ifndef static_assert
41#define static_assert(x, y) ((void)0)
42#endif
43#endif
44
45namespace dtc {
46
47/**
48 * Type for a buffer of bytes.  This is used for a lot of short-lived temporary
49 * variables, so may eventually be changed to something like LLVM's
50 * SmallVector, but currently the program runs in a tiny fraction of a second,
51 * so this is not an issue.
52 */
53typedef std::vector<uint8_t> byte_buffer;
54
55/**
56 * Helper function to push a big endian value into a byte buffer.  We use
57 * native-endian values for all of the in-memory data structures and only
58 * transform them into big endian form for output.
59 */
60template<typename T>
61inline void push_big_endian(byte_buffer &v, T val)
62{
63	static_assert(sizeof(T) > 1,
64		"Big endian doesn't make sense for single-byte values");
65	for (int bit=(sizeof(T) - 1)*8 ; bit>=0 ; bit-= 8)
66	{
67		v.push_back((val >> bit) & 0xff);
68	}
69}
70
71/**
72 * Simple inline non-locale-aware check that this is a valid ASCII
73 * digit.
74 */
75inline bool isdigit(char c)
76{
77	return (c >= '0') && (c <= '9');
78}
79
80/**
81 * Simple inline non-locale-aware check that this is a valid ASCII
82 * hex digit.
83 */
84inline bool ishexdigit(char c)
85{
86	return ((c >= '0') && (c <= '9')) || ((c >= 'a') && (c <= 'f')) ||
87		((c >= 'A') && (c <= 'Z'));
88}
89
90}// namespace dtc
91
92#endif // !_UTIL_HH_
93