xref: /freebsd/usr.bin/dtc/util.hh (revision 4928135658a9d0eaee37003df6137ab363fcb0b4)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2013 David Chisnall
5  * All rights reserved.
6  *
7  * This software was developed by SRI International and the University of
8  * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
9  * ("CTSRD"), as part of the DARPA CRASH research programme.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $FreeBSD$
33  */
34 
35 #ifndef _UTIL_HH_
36 #define _UTIL_HH_
37 
38 #include <vector>
39 
40 // If we aren't using C++11, then just ignore static asserts.
41 #if __cplusplus < 201103L
42 #ifndef static_assert
43 #define static_assert(x, y) ((void)0)
44 #endif
45 #endif
46 
47 namespace dtc {
48 
49 /**
50  * Type for a buffer of bytes.  This is used for a lot of short-lived temporary
51  * variables, so may eventually be changed to something like LLVM's
52  * SmallVector, but currently the program runs in a tiny fraction of a second,
53  * so this is not an issue.
54  */
55 typedef std::vector<uint8_t> byte_buffer;
56 
57 /**
58  * Helper function to push a big endian value into a byte buffer.  We use
59  * native-endian values for all of the in-memory data structures and only
60  * transform them into big endian form for output.
61  */
62 template<typename T>
63 inline void push_big_endian(byte_buffer &v, T val)
64 {
65 	static_assert(sizeof(T) > 1,
66 		"Big endian doesn't make sense for single-byte values");
67 	for (int bit=(sizeof(T) - 1)*8 ; bit>=0 ; bit-= 8)
68 	{
69 		v.push_back((val >> bit) & 0xff);
70 	}
71 }
72 
73 void push_string(byte_buffer &v, const std::string &s, bool escapes=false);
74 
75 /**
76  * Simple inline non-locale-aware check that this is a valid ASCII
77  * digit.
78  */
79 inline bool isdigit(char c)
80 {
81 	return (c >= '0') && (c <= '9');
82 }
83 
84 /**
85  * Simple inline non-locale-aware check that this is a valid ASCII
86  * hex digit.
87  */
88 inline bool ishexdigit(char c)
89 {
90 	return ((c >= '0') && (c <= '9')) || ((c >= 'a') && (c <= 'f')) ||
91 		((c >= 'A') && (c <= 'F'));
92 }
93 
94 /**
95  * Simple inline non-locale-aware check that this is a valid ASCII
96  * letter.
97  */
98 inline bool isalpha(char c)
99 {
100 	return ((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z'));
101 }
102 
103 /**
104  * A wrapper around dirname(3) that handles inconsistencies relating to memory
105  * management between platforms and provides a std::string interface.
106  */
107 std::string dirname(const std::string&);
108 
109 /**
110  * A wrapper around basename(3) that handles inconsistencies relating to memory
111  * management between platforms and provides a std::string interface.
112  */
113 std::string basename(const std::string&);
114 
115 }// namespace dtc
116 
117 #endif // !_UTIL_HH_
118