xref: /freebsd/usr.bin/dtc/string.cc (revision 009f7b425d0046197035b97e71153908303619c2)
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 #include "string.hh"
34 #include <ctype.h>
35 #include <stdio.h>
36 
37 namespace
38 {
39 /**
40  * The source files are ASCII, so we provide a non-locale-aware version of
41  * isalpha.  This is a class so that it can be used with a template function
42  * for parsing strings.
43  */
44 struct is_alpha
45 {
46 	static inline bool check(const char c)
47 	{
48 		return ((c >= 'a') && (c <= 'z')) || ((c >= 'A') &&
49 			(c <= 'Z'));
50 	}
51 };
52 /**
53  * Check whether a character is in the set allowed for node names.  This is a
54  * class so that it can be used with a template function for parsing strings.
55  */
56 struct is_node_name_character
57 {
58 	static inline bool check(const char c)
59 	{
60 		switch(c)
61 		{
62 			default:
63 				return false;
64 			case 'a'...'z': case 'A'...'Z': case '0'...'9':
65 			case ',': case '.': case '+': case '-':
66 			case '_':
67 				return true;
68 		}
69 	}
70 };
71 /**
72  * Check whether a character is in the set allowed for property names.  This is
73  * a class so that it can be used with a template function for parsing strings.
74  */
75 struct is_property_name_character
76 {
77 	static inline bool check(const char c)
78 	{
79 		switch(c)
80 		{
81 			default:
82 				return false;
83 			case 'a'...'z': case 'A'...'Z': case '0'...'9':
84 			case ',': case '.': case '+': case '-':
85 			case '_': case '#':
86 				return true;
87 		}
88 	}
89 };
90 
91 }
92 
93 namespace dtc
94 {
95 
96 template<class T> string
97 string::parse(input_buffer &s)
98 {
99 	const char *start = s;
100 	int l=0;
101 	while (T::check(*s)) { l++; ++s; }
102 	return string(start, l);
103 }
104 
105 string::string(input_buffer &s) : start((const char*)s), length(0)
106 {
107 	while(s[length] != '\0')
108 	{
109 		length++;
110 	}
111 }
112 
113 string
114 string::parse_node_name(input_buffer &s)
115 {
116 	return parse<is_node_name_character>(s);
117 }
118 
119 string
120 string::parse_property_name(input_buffer &s)
121 {
122 	return parse<is_property_name_character>(s);
123 }
124 string
125 string::parse_node_or_property_name(input_buffer &s, bool &is_property)
126 {
127 	if (is_property)
128 	{
129 		return parse_property_name(s);
130 	}
131 	const char *start = s;
132 	int l=0;
133 	while (is_node_name_character::check(*s))
134 	{
135 		l++;
136 		++s;
137 	}
138 	while (is_property_name_character::check(*s))
139 	{
140 		l++;
141 		++s;
142 		is_property = true;
143 	}
144 	return string(start, l);
145 }
146 
147 bool
148 string::operator==(const string& other) const
149 {
150 	return (length == other.length) &&
151 	       (memcmp(start, other.start, length) == 0);
152 }
153 
154 bool
155 string::operator==(const char *other) const
156 {
157 	return strncmp(other, start, length) == 0;
158 }
159 
160 bool
161 string::operator<(const string& other) const
162 {
163 	if (length < other.length) { return true; }
164 	if (length > other.length) { return false; }
165 	return memcmp(start, other.start, length) < 0;
166 }
167 
168 void
169 string::push_to_buffer(byte_buffer &buffer, bool escapes)
170 {
171 	for (int i=0 ; i<length ; ++i)
172 	{
173 		uint8_t c = start[i];
174 		if (escapes && c == '\\' && i+1 < length)
175 		{
176 			c = start[++i];
177 			switch (c)
178 			{
179 				// For now, we just ignore invalid escape sequences.
180 				default:
181 				case '"':
182 				case '\'':
183 				case '\\':
184 					break;
185 				case 'a':
186 					c = '\a';
187 					break;
188 				case 'b':
189 					c = '\b';
190 					break;
191 				case 't':
192 					c = '\t';
193 					break;
194 				case 'n':
195 					c = '\n';
196 					break;
197 				case 'v':
198 					c = '\v';
199 					break;
200 				case 'f':
201 					c = '\f';
202 					break;
203 				case 'r':
204 					c = '\r';
205 					break;
206 				case '0'...'7':
207 				{
208 					int v = digittoint(c);
209 					if (i+1 < length && start[i+1] <= '7' && start[i+1] >= '0')
210 					{
211 						v <<= 3;
212 						v |= digittoint(start[i+1]);
213 						i++;
214 						if (i+1 < length && start[i+1] <= '7' && start[i+1] >= '0')
215 						{
216 							v <<= 3;
217 							v |= digittoint(start[i+1]);
218 						}
219 					}
220 					c = (uint8_t)v;
221 					break;
222 				}
223 				case 'x':
224 				{
225 					++i;
226 					if (i >= length)
227 					{
228 						break;
229 					}
230 					int v = digittoint(start[i]);
231 					if (i+1 < length && ishexdigit(start[i+1]))
232 					{
233 						v <<= 4;
234 						v |= digittoint(start[++i]);
235 					}
236 					c = (uint8_t)v;
237 					break;
238 				}
239 			}
240 		}
241 		buffer.push_back(c);
242 	}
243 }
244 
245 void
246 string::print(FILE *file)
247 {
248 	fwrite(start, length, 1, file);
249 }
250 
251 void
252 string::dump()
253 {
254 	print(stderr);
255 }
256 
257 } // namespace dtc
258 
259