1 //===-- StringExtractor.cpp -------------------------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "Utility/StringExtractor.h"
11
12 // C Includes
13 #include <stdlib.h>
14
15 // C++ Includes
16 // Other libraries and framework includes
17 // Project includes
18
19 static const uint8_t
20 g_hex_ascii_to_hex_integer[256] = {
21
22 255, 255, 255, 255, 255, 255, 255, 255,
23 255, 255, 255, 255, 255, 255, 255, 255,
24 255, 255, 255, 255, 255, 255, 255, 255,
25 255, 255, 255, 255, 255, 255, 255, 255,
26 255, 255, 255, 255, 255, 255, 255, 255,
27 255, 255, 255, 255, 255, 255, 255, 255,
28 0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
29 0x8, 0x9, 255, 255, 255, 255, 255, 255,
30 255, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 255,
31 255, 255, 255, 255, 255, 255, 255, 255,
32 255, 255, 255, 255, 255, 255, 255, 255,
33 255, 255, 255, 255, 255, 255, 255, 255,
34 255, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 255,
35 255, 255, 255, 255, 255, 255, 255, 255,
36 255, 255, 255, 255, 255, 255, 255, 255,
37 255, 255, 255, 255, 255, 255, 255, 255,
38 255, 255, 255, 255, 255, 255, 255, 255,
39 255, 255, 255, 255, 255, 255, 255, 255,
40 255, 255, 255, 255, 255, 255, 255, 255,
41 255, 255, 255, 255, 255, 255, 255, 255,
42 255, 255, 255, 255, 255, 255, 255, 255,
43 255, 255, 255, 255, 255, 255, 255, 255,
44 255, 255, 255, 255, 255, 255, 255, 255,
45 255, 255, 255, 255, 255, 255, 255, 255,
46 255, 255, 255, 255, 255, 255, 255, 255,
47 255, 255, 255, 255, 255, 255, 255, 255,
48 255, 255, 255, 255, 255, 255, 255, 255,
49 255, 255, 255, 255, 255, 255, 255, 255,
50 255, 255, 255, 255, 255, 255, 255, 255,
51 255, 255, 255, 255, 255, 255, 255, 255,
52 255, 255, 255, 255, 255, 255, 255, 255,
53 255, 255, 255, 255, 255, 255, 255, 255,
54 };
55
56 static inline int
xdigit_to_sint(char ch)57 xdigit_to_sint (char ch)
58 {
59 if (ch >= 'a' && ch <= 'f')
60 return 10 + ch - 'a';
61 if (ch >= 'A' && ch <= 'F')
62 return 10 + ch - 'A';
63 return ch - '0';
64 }
65
66 static inline unsigned int
xdigit_to_uint(uint8_t ch)67 xdigit_to_uint (uint8_t ch)
68 {
69 if (ch >= 'a' && ch <= 'f')
70 return 10u + ch - 'a';
71 if (ch >= 'A' && ch <= 'F')
72 return 10u + ch - 'A';
73 return ch - '0';
74 }
75
76 //----------------------------------------------------------------------
77 // StringExtractor constructor
78 //----------------------------------------------------------------------
StringExtractor()79 StringExtractor::StringExtractor() :
80 m_packet(),
81 m_index (0)
82 {
83 }
84
85
StringExtractor(const char * packet_cstr)86 StringExtractor::StringExtractor(const char *packet_cstr) :
87 m_packet(),
88 m_index (0)
89 {
90 if (packet_cstr)
91 m_packet.assign (packet_cstr);
92 }
93
94
95 //----------------------------------------------------------------------
96 // StringExtractor copy constructor
97 //----------------------------------------------------------------------
StringExtractor(const StringExtractor & rhs)98 StringExtractor::StringExtractor(const StringExtractor& rhs) :
99 m_packet (rhs.m_packet),
100 m_index (rhs.m_index)
101 {
102
103 }
104
105 //----------------------------------------------------------------------
106 // StringExtractor assignment operator
107 //----------------------------------------------------------------------
108 const StringExtractor&
operator =(const StringExtractor & rhs)109 StringExtractor::operator=(const StringExtractor& rhs)
110 {
111 if (this != &rhs)
112 {
113 m_packet = rhs.m_packet;
114 m_index = rhs.m_index;
115
116 }
117 return *this;
118 }
119
120 //----------------------------------------------------------------------
121 // Destructor
122 //----------------------------------------------------------------------
~StringExtractor()123 StringExtractor::~StringExtractor()
124 {
125 }
126
127
128 char
GetChar(char fail_value)129 StringExtractor::GetChar (char fail_value)
130 {
131 if (m_index < m_packet.size())
132 {
133 char ch = m_packet[m_index];
134 ++m_index;
135 return ch;
136 }
137 m_index = UINT64_MAX;
138 return fail_value;
139 }
140
141 //----------------------------------------------------------------------
142 // Extract an unsigned character from two hex ASCII chars in the packet
143 // string
144 //----------------------------------------------------------------------
145 uint8_t
GetHexU8(uint8_t fail_value,bool set_eof_on_fail)146 StringExtractor::GetHexU8 (uint8_t fail_value, bool set_eof_on_fail)
147 {
148 uint32_t i = m_index;
149 if ((i + 2) <= m_packet.size())
150 {
151 const uint8_t hi_nibble = g_hex_ascii_to_hex_integer[static_cast<uint8_t>(m_packet[i])];
152 const uint8_t lo_nibble = g_hex_ascii_to_hex_integer[static_cast<uint8_t>(m_packet[i+1])];
153 if (hi_nibble < 16 && lo_nibble < 16)
154 {
155 m_index += 2;
156 return (hi_nibble << 4) + lo_nibble;
157 }
158 }
159 if (set_eof_on_fail || m_index >= m_packet.size())
160 m_index = UINT64_MAX;
161 return fail_value;
162 }
163
164 uint32_t
GetU32(uint32_t fail_value,int base)165 StringExtractor::GetU32 (uint32_t fail_value, int base)
166 {
167 if (m_index < m_packet.size())
168 {
169 char *end = NULL;
170 const char *start = m_packet.c_str();
171 const char *uint_cstr = start + m_index;
172 uint32_t result = ::strtoul (uint_cstr, &end, base);
173
174 if (end && end != uint_cstr)
175 {
176 m_index = end - start;
177 return result;
178 }
179 }
180 return fail_value;
181 }
182
183
184 uint32_t
GetHexMaxU32(bool little_endian,uint32_t fail_value)185 StringExtractor::GetHexMaxU32 (bool little_endian, uint32_t fail_value)
186 {
187 uint32_t result = 0;
188 uint32_t nibble_count = 0;
189
190 if (little_endian)
191 {
192 uint32_t shift_amount = 0;
193 while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
194 {
195 // Make sure we don't exceed the size of a uint32_t...
196 if (nibble_count >= (sizeof(uint32_t) * 2))
197 {
198 m_index = UINT64_MAX;
199 return fail_value;
200 }
201
202 uint8_t nibble_lo;
203 uint8_t nibble_hi = xdigit_to_sint (m_packet[m_index]);
204 ++m_index;
205 if (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
206 {
207 nibble_lo = xdigit_to_sint (m_packet[m_index]);
208 ++m_index;
209 result |= ((uint32_t)nibble_hi << (shift_amount + 4));
210 result |= ((uint32_t)nibble_lo << shift_amount);
211 nibble_count += 2;
212 shift_amount += 8;
213 }
214 else
215 {
216 result |= ((uint32_t)nibble_hi << shift_amount);
217 nibble_count += 1;
218 shift_amount += 4;
219 }
220
221 }
222 }
223 else
224 {
225 while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
226 {
227 // Make sure we don't exceed the size of a uint32_t...
228 if (nibble_count >= (sizeof(uint32_t) * 2))
229 {
230 m_index = UINT64_MAX;
231 return fail_value;
232 }
233
234 uint8_t nibble = xdigit_to_sint (m_packet[m_index]);
235 // Big Endian
236 result <<= 4;
237 result |= nibble;
238
239 ++m_index;
240 ++nibble_count;
241 }
242 }
243 return result;
244 }
245
246 uint64_t
GetHexMaxU64(bool little_endian,uint64_t fail_value)247 StringExtractor::GetHexMaxU64 (bool little_endian, uint64_t fail_value)
248 {
249 uint64_t result = 0;
250 uint32_t nibble_count = 0;
251
252 if (little_endian)
253 {
254 uint32_t shift_amount = 0;
255 while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
256 {
257 // Make sure we don't exceed the size of a uint64_t...
258 if (nibble_count >= (sizeof(uint64_t) * 2))
259 {
260 m_index = UINT64_MAX;
261 return fail_value;
262 }
263
264 uint8_t nibble_lo;
265 uint8_t nibble_hi = xdigit_to_sint (m_packet[m_index]);
266 ++m_index;
267 if (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
268 {
269 nibble_lo = xdigit_to_sint (m_packet[m_index]);
270 ++m_index;
271 result |= ((uint64_t)nibble_hi << (shift_amount + 4));
272 result |= ((uint64_t)nibble_lo << shift_amount);
273 nibble_count += 2;
274 shift_amount += 8;
275 }
276 else
277 {
278 result |= ((uint64_t)nibble_hi << shift_amount);
279 nibble_count += 1;
280 shift_amount += 4;
281 }
282
283 }
284 }
285 else
286 {
287 while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
288 {
289 // Make sure we don't exceed the size of a uint64_t...
290 if (nibble_count >= (sizeof(uint64_t) * 2))
291 {
292 m_index = UINT64_MAX;
293 return fail_value;
294 }
295
296 uint8_t nibble = xdigit_to_sint (m_packet[m_index]);
297 // Big Endian
298 result <<= 4;
299 result |= nibble;
300
301 ++m_index;
302 ++nibble_count;
303 }
304 }
305 return result;
306 }
307
308 size_t
GetHexBytes(void * dst_void,size_t dst_len,uint8_t fail_fill_value)309 StringExtractor::GetHexBytes (void *dst_void, size_t dst_len, uint8_t fail_fill_value)
310 {
311 uint8_t *dst = (uint8_t*)dst_void;
312 size_t bytes_extracted = 0;
313 while (bytes_extracted < dst_len && GetBytesLeft ())
314 {
315 dst[bytes_extracted] = GetHexU8 (fail_fill_value);
316 if (IsGood())
317 ++bytes_extracted;
318 else
319 break;
320 }
321
322 for (size_t i = bytes_extracted; i < dst_len; ++i)
323 dst[i] = fail_fill_value;
324
325 return bytes_extracted;
326 }
327
328
329 // Consume ASCII hex nibble character pairs until we have decoded byte_size
330 // bytes of data.
331
332 uint64_t
GetHexWithFixedSize(uint32_t byte_size,bool little_endian,uint64_t fail_value)333 StringExtractor::GetHexWithFixedSize (uint32_t byte_size, bool little_endian, uint64_t fail_value)
334 {
335 if (byte_size <= 8 && GetBytesLeft() >= byte_size * 2)
336 {
337 uint64_t result = 0;
338 uint32_t i;
339 if (little_endian)
340 {
341 // Little Endian
342 uint32_t shift_amount;
343 for (i = 0, shift_amount = 0;
344 i < byte_size && IsGood();
345 ++i, shift_amount += 8)
346 {
347 result |= ((uint64_t)GetHexU8() << shift_amount);
348 }
349 }
350 else
351 {
352 // Big Endian
353 for (i = 0; i < byte_size && IsGood(); ++i)
354 {
355 result <<= 8;
356 result |= GetHexU8();
357 }
358 }
359 }
360 m_index = UINT64_MAX;
361 return fail_value;
362 }
363
364 size_t
GetHexByteString(std::string & str)365 StringExtractor::GetHexByteString (std::string &str)
366 {
367 str.clear();
368 char ch;
369 while ((ch = GetHexU8()) != '\0')
370 str.append(1, ch);
371 return str.size();
372 }
373
374 bool
GetNameColonValue(std::string & name,std::string & value)375 StringExtractor::GetNameColonValue (std::string &name, std::string &value)
376 {
377 // Read something in the form of NNNN:VVVV; where NNNN is any character
378 // that is not a colon, followed by a ':' character, then a value (one or
379 // more ';' chars), followed by a ';'
380 if (m_index < m_packet.size())
381 {
382 const size_t colon_idx = m_packet.find (':', m_index);
383 if (colon_idx != std::string::npos)
384 {
385 const size_t semicolon_idx = m_packet.find (';', colon_idx);
386 if (semicolon_idx != std::string::npos)
387 {
388 name.assign (m_packet, m_index, colon_idx - m_index);
389 value.assign (m_packet, colon_idx + 1, semicolon_idx - (colon_idx + 1));
390 m_index = semicolon_idx + 1;
391 return true;
392 }
393 }
394 }
395 m_index = UINT64_MAX;
396 return false;
397 }
398