1 //===-- DataExtractor.cpp ---------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Utility/DataExtractor.h"
10 
11 #include "lldb/lldb-defines.h"
12 #include "lldb/lldb-enumerations.h"
13 #include "lldb/lldb-forward.h"
14 #include "lldb/lldb-types.h"
15 
16 #include "lldb/Utility/DataBuffer.h"
17 #include "lldb/Utility/DataBufferHeap.h"
18 #include "lldb/Utility/Endian.h"
19 #include "lldb/Utility/LLDBAssert.h"
20 #include "lldb/Utility/Log.h"
21 #include "lldb/Utility/Stream.h"
22 #include "lldb/Utility/StreamString.h"
23 #include "lldb/Utility/UUID.h"
24 
25 #include "llvm/ADT/ArrayRef.h"
26 #include "llvm/ADT/SmallVector.h"
27 #include "llvm/Support/MD5.h"
28 #include "llvm/Support/MathExtras.h"
29 
30 #include <algorithm>
31 #include <array>
32 #include <cassert>
33 #include <cstdint>
34 #include <string>
35 
36 #include <ctype.h>
37 #include <inttypes.h>
38 #include <string.h>
39 
40 using namespace lldb;
41 using namespace lldb_private;
42 
43 static inline uint16_t ReadInt16(const unsigned char *ptr, offset_t offset) {
44   uint16_t value;
45   memcpy(&value, ptr + offset, 2);
46   return value;
47 }
48 
49 static inline uint32_t ReadInt32(const unsigned char *ptr,
50                                  offset_t offset = 0) {
51   uint32_t value;
52   memcpy(&value, ptr + offset, 4);
53   return value;
54 }
55 
56 static inline uint64_t ReadInt64(const unsigned char *ptr,
57                                  offset_t offset = 0) {
58   uint64_t value;
59   memcpy(&value, ptr + offset, 8);
60   return value;
61 }
62 
63 static inline uint16_t ReadInt16(const void *ptr) {
64   uint16_t value;
65   memcpy(&value, ptr, 2);
66   return value;
67 }
68 
69 static inline uint16_t ReadSwapInt16(const unsigned char *ptr,
70                                      offset_t offset) {
71   uint16_t value;
72   memcpy(&value, ptr + offset, 2);
73   return llvm::ByteSwap_16(value);
74 }
75 
76 static inline uint32_t ReadSwapInt32(const unsigned char *ptr,
77                                      offset_t offset) {
78   uint32_t value;
79   memcpy(&value, ptr + offset, 4);
80   return llvm::ByteSwap_32(value);
81 }
82 
83 static inline uint64_t ReadSwapInt64(const unsigned char *ptr,
84                                      offset_t offset) {
85   uint64_t value;
86   memcpy(&value, ptr + offset, 8);
87   return llvm::ByteSwap_64(value);
88 }
89 
90 static inline uint16_t ReadSwapInt16(const void *ptr) {
91   uint16_t value;
92   memcpy(&value, ptr, 2);
93   return llvm::ByteSwap_16(value);
94 }
95 
96 static inline uint32_t ReadSwapInt32(const void *ptr) {
97   uint32_t value;
98   memcpy(&value, ptr, 4);
99   return llvm::ByteSwap_32(value);
100 }
101 
102 static inline uint64_t ReadSwapInt64(const void *ptr) {
103   uint64_t value;
104   memcpy(&value, ptr, 8);
105   return llvm::ByteSwap_64(value);
106 }
107 
108 static inline uint64_t ReadMaxInt64(const uint8_t *data, size_t byte_size,
109                                     ByteOrder byte_order) {
110   uint64_t res = 0;
111   if (byte_order == eByteOrderBig)
112     for (size_t i = 0; i < byte_size; ++i)
113       res = (res << 8) | data[i];
114   else {
115     assert(byte_order == eByteOrderLittle);
116     for (size_t i = 0; i < byte_size; ++i)
117       res = (res << 8) | data[byte_size - 1 - i];
118   }
119   return res;
120 }
121 
122 DataExtractor::DataExtractor()
123     : m_start(nullptr), m_end(nullptr),
124       m_byte_order(endian::InlHostByteOrder()), m_addr_size(sizeof(void *)),
125       m_data_sp(), m_target_byte_size(1) {}
126 
127 //----------------------------------------------------------------------
128 // This constructor allows us to use data that is owned by someone else. The
129 // data must stay around as long as this object is valid.
130 //----------------------------------------------------------------------
131 DataExtractor::DataExtractor(const void *data, offset_t length,
132                              ByteOrder endian, uint32_t addr_size,
133                              uint32_t target_byte_size /*=1*/)
134     : m_start(const_cast<uint8_t *>(reinterpret_cast<const uint8_t *>(data))),
135       m_end(const_cast<uint8_t *>(reinterpret_cast<const uint8_t *>(data)) +
136             length),
137       m_byte_order(endian), m_addr_size(addr_size), m_data_sp(),
138       m_target_byte_size(target_byte_size) {
139   assert(addr_size == 4 || addr_size == 8);
140 }
141 
142 //----------------------------------------------------------------------
143 // Make a shared pointer reference to the shared data in "data_sp" and set the
144 // endian swapping setting to "swap", and the address size to "addr_size". The
145 // shared data reference will ensure the data lives as long as any
146 // DataExtractor objects exist that have a reference to this data.
147 //----------------------------------------------------------------------
148 DataExtractor::DataExtractor(const DataBufferSP &data_sp, ByteOrder endian,
149                              uint32_t addr_size,
150                              uint32_t target_byte_size /*=1*/)
151     : m_start(nullptr), m_end(nullptr), m_byte_order(endian),
152       m_addr_size(addr_size), m_data_sp(),
153       m_target_byte_size(target_byte_size) {
154   assert(addr_size == 4 || addr_size == 8);
155   SetData(data_sp);
156 }
157 
158 //----------------------------------------------------------------------
159 // Initialize this object with a subset of the data bytes in "data". If "data"
160 // contains shared data, then a reference to this shared data will added and
161 // the shared data will stay around as long as any object contains a reference
162 // to that data. The endian swap and address size settings are copied from
163 // "data".
164 //----------------------------------------------------------------------
165 DataExtractor::DataExtractor(const DataExtractor &data, offset_t offset,
166                              offset_t length, uint32_t target_byte_size /*=1*/)
167     : m_start(nullptr), m_end(nullptr), m_byte_order(data.m_byte_order),
168       m_addr_size(data.m_addr_size), m_data_sp(),
169       m_target_byte_size(target_byte_size) {
170   assert(m_addr_size == 4 || m_addr_size == 8);
171   if (data.ValidOffset(offset)) {
172     offset_t bytes_available = data.GetByteSize() - offset;
173     if (length > bytes_available)
174       length = bytes_available;
175     SetData(data, offset, length);
176   }
177 }
178 
179 DataExtractor::DataExtractor(const DataExtractor &rhs)
180     : m_start(rhs.m_start), m_end(rhs.m_end), m_byte_order(rhs.m_byte_order),
181       m_addr_size(rhs.m_addr_size), m_data_sp(rhs.m_data_sp),
182       m_target_byte_size(rhs.m_target_byte_size) {
183   assert(m_addr_size == 4 || m_addr_size == 8);
184 }
185 
186 //----------------------------------------------------------------------
187 // Assignment operator
188 //----------------------------------------------------------------------
189 const DataExtractor &DataExtractor::operator=(const DataExtractor &rhs) {
190   if (this != &rhs) {
191     m_start = rhs.m_start;
192     m_end = rhs.m_end;
193     m_byte_order = rhs.m_byte_order;
194     m_addr_size = rhs.m_addr_size;
195     m_data_sp = rhs.m_data_sp;
196   }
197   return *this;
198 }
199 
200 DataExtractor::~DataExtractor() = default;
201 
202 //------------------------------------------------------------------
203 // Clears the object contents back to a default invalid state, and release any
204 // references to shared data that this object may contain.
205 //------------------------------------------------------------------
206 void DataExtractor::Clear() {
207   m_start = nullptr;
208   m_end = nullptr;
209   m_byte_order = endian::InlHostByteOrder();
210   m_addr_size = sizeof(void *);
211   m_data_sp.reset();
212 }
213 
214 //------------------------------------------------------------------
215 // If this object contains shared data, this function returns the offset into
216 // that shared data. Else zero is returned.
217 //------------------------------------------------------------------
218 size_t DataExtractor::GetSharedDataOffset() const {
219   if (m_start != nullptr) {
220     const DataBuffer *data = m_data_sp.get();
221     if (data != nullptr) {
222       const uint8_t *data_bytes = data->GetBytes();
223       if (data_bytes != nullptr) {
224         assert(m_start >= data_bytes);
225         return m_start - data_bytes;
226       }
227     }
228   }
229   return 0;
230 }
231 
232 //----------------------------------------------------------------------
233 // Set the data with which this object will extract from to data starting at
234 // BYTES and set the length of the data to LENGTH bytes long. The data is
235 // externally owned must be around at least as long as this object points to
236 // the data. No copy of the data is made, this object just refers to this data
237 // and can extract from it. If this object refers to any shared data upon
238 // entry, the reference to that data will be released. Is SWAP is set to true,
239 // any data extracted will be endian swapped.
240 //----------------------------------------------------------------------
241 lldb::offset_t DataExtractor::SetData(const void *bytes, offset_t length,
242                                       ByteOrder endian) {
243   m_byte_order = endian;
244   m_data_sp.reset();
245   if (bytes == nullptr || length == 0) {
246     m_start = nullptr;
247     m_end = nullptr;
248   } else {
249     m_start = const_cast<uint8_t *>(reinterpret_cast<const uint8_t *>(bytes));
250     m_end = m_start + length;
251   }
252   return GetByteSize();
253 }
254 
255 //----------------------------------------------------------------------
256 // Assign the data for this object to be a subrange in "data" starting
257 // "data_offset" bytes into "data" and ending "data_length" bytes later. If
258 // "data_offset" is not a valid offset into "data", then this object will
259 // contain no bytes. If "data_offset" is within "data" yet "data_length" is too
260 // large, the length will be capped at the number of bytes remaining in "data".
261 // If "data" contains a shared pointer to other data, then a ref counted
262 // pointer to that data will be made in this object. If "data" doesn't contain
263 // a shared pointer to data, then the bytes referred to in "data" will need to
264 // exist at least as long as this object refers to those bytes. The address
265 // size and endian swap settings are copied from the current values in "data".
266 //----------------------------------------------------------------------
267 lldb::offset_t DataExtractor::SetData(const DataExtractor &data,
268                                       offset_t data_offset,
269                                       offset_t data_length) {
270   m_addr_size = data.m_addr_size;
271   assert(m_addr_size == 4 || m_addr_size == 8);
272   // If "data" contains shared pointer to data, then we can use that
273   if (data.m_data_sp) {
274     m_byte_order = data.m_byte_order;
275     return SetData(data.m_data_sp, data.GetSharedDataOffset() + data_offset,
276                    data_length);
277   }
278 
279   // We have a DataExtractor object that just has a pointer to bytes
280   if (data.ValidOffset(data_offset)) {
281     if (data_length > data.GetByteSize() - data_offset)
282       data_length = data.GetByteSize() - data_offset;
283     return SetData(data.GetDataStart() + data_offset, data_length,
284                    data.GetByteOrder());
285   }
286   return 0;
287 }
288 
289 //----------------------------------------------------------------------
290 // Assign the data for this object to be a subrange of the shared data in
291 // "data_sp" starting "data_offset" bytes into "data_sp" and ending
292 // "data_length" bytes later. If "data_offset" is not a valid offset into
293 // "data_sp", then this object will contain no bytes. If "data_offset" is
294 // within "data_sp" yet "data_length" is too large, the length will be capped
295 // at the number of bytes remaining in "data_sp". A ref counted pointer to the
296 // data in "data_sp" will be made in this object IF the number of bytes this
297 // object refers to in greater than zero (if at least one byte was available
298 // starting at "data_offset") to ensure the data stays around as long as it is
299 // needed. The address size and endian swap settings will remain unchanged from
300 // their current settings.
301 //----------------------------------------------------------------------
302 lldb::offset_t DataExtractor::SetData(const DataBufferSP &data_sp,
303                                       offset_t data_offset,
304                                       offset_t data_length) {
305   m_start = m_end = nullptr;
306 
307   if (data_length > 0) {
308     m_data_sp = data_sp;
309     if (data_sp) {
310       const size_t data_size = data_sp->GetByteSize();
311       if (data_offset < data_size) {
312         m_start = data_sp->GetBytes() + data_offset;
313         const size_t bytes_left = data_size - data_offset;
314         // Cap the length of we asked for too many
315         if (data_length <= bytes_left)
316           m_end = m_start + data_length; // We got all the bytes we wanted
317         else
318           m_end = m_start + bytes_left; // Not all the bytes requested were
319                                         // available in the shared data
320       }
321     }
322   }
323 
324   size_t new_size = GetByteSize();
325 
326   // Don't hold a shared pointer to the data buffer if we don't share any valid
327   // bytes in the shared buffer.
328   if (new_size == 0)
329     m_data_sp.reset();
330 
331   return new_size;
332 }
333 
334 //----------------------------------------------------------------------
335 // Extract a single unsigned char from the binary data and update the offset
336 // pointed to by "offset_ptr".
337 //
338 // RETURNS the byte that was extracted, or zero on failure.
339 //----------------------------------------------------------------------
340 uint8_t DataExtractor::GetU8(offset_t *offset_ptr) const {
341   const uint8_t *data = (const uint8_t *)GetData(offset_ptr, 1);
342   if (data)
343     return *data;
344   return 0;
345 }
346 
347 //----------------------------------------------------------------------
348 // Extract "count" unsigned chars from the binary data and update the offset
349 // pointed to by "offset_ptr". The extracted data is copied into "dst".
350 //
351 // RETURNS the non-nullptr buffer pointer upon successful extraction of
352 // all the requested bytes, or nullptr when the data is not available in the
353 // buffer due to being out of bounds, or insufficient data.
354 //----------------------------------------------------------------------
355 void *DataExtractor::GetU8(offset_t *offset_ptr, void *dst,
356                            uint32_t count) const {
357   const uint8_t *data = (const uint8_t *)GetData(offset_ptr, count);
358   if (data) {
359     // Copy the data into the buffer
360     memcpy(dst, data, count);
361     // Return a non-nullptr pointer to the converted data as an indicator of
362     // success
363     return dst;
364   }
365   return nullptr;
366 }
367 
368 //----------------------------------------------------------------------
369 // Extract a single uint16_t from the data and update the offset pointed to by
370 // "offset_ptr".
371 //
372 // RETURNS the uint16_t that was extracted, or zero on failure.
373 //----------------------------------------------------------------------
374 uint16_t DataExtractor::GetU16(offset_t *offset_ptr) const {
375   uint16_t val = 0;
376   const uint8_t *data = (const uint8_t *)GetData(offset_ptr, sizeof(val));
377   if (data) {
378     if (m_byte_order != endian::InlHostByteOrder())
379       val = ReadSwapInt16(data);
380     else
381       val = ReadInt16(data);
382   }
383   return val;
384 }
385 
386 uint16_t DataExtractor::GetU16_unchecked(offset_t *offset_ptr) const {
387   uint16_t val;
388   if (m_byte_order == endian::InlHostByteOrder())
389     val = ReadInt16(m_start, *offset_ptr);
390   else
391     val = ReadSwapInt16(m_start, *offset_ptr);
392   *offset_ptr += sizeof(val);
393   return val;
394 }
395 
396 uint32_t DataExtractor::GetU32_unchecked(offset_t *offset_ptr) const {
397   uint32_t val;
398   if (m_byte_order == endian::InlHostByteOrder())
399     val = ReadInt32(m_start, *offset_ptr);
400   else
401     val = ReadSwapInt32(m_start, *offset_ptr);
402   *offset_ptr += sizeof(val);
403   return val;
404 }
405 
406 uint64_t DataExtractor::GetU64_unchecked(offset_t *offset_ptr) const {
407   uint64_t val;
408   if (m_byte_order == endian::InlHostByteOrder())
409     val = ReadInt64(m_start, *offset_ptr);
410   else
411     val = ReadSwapInt64(m_start, *offset_ptr);
412   *offset_ptr += sizeof(val);
413   return val;
414 }
415 
416 //----------------------------------------------------------------------
417 // Extract "count" uint16_t values from the binary data and update the offset
418 // pointed to by "offset_ptr". The extracted data is copied into "dst".
419 //
420 // RETURNS the non-nullptr buffer pointer upon successful extraction of
421 // all the requested bytes, or nullptr when the data is not available in the
422 // buffer due to being out of bounds, or insufficient data.
423 //----------------------------------------------------------------------
424 void *DataExtractor::GetU16(offset_t *offset_ptr, void *void_dst,
425                             uint32_t count) const {
426   const size_t src_size = sizeof(uint16_t) * count;
427   const uint16_t *src = (const uint16_t *)GetData(offset_ptr, src_size);
428   if (src) {
429     if (m_byte_order != endian::InlHostByteOrder()) {
430       uint16_t *dst_pos = (uint16_t *)void_dst;
431       uint16_t *dst_end = dst_pos + count;
432       const uint16_t *src_pos = src;
433       while (dst_pos < dst_end) {
434         *dst_pos = ReadSwapInt16(src_pos);
435         ++dst_pos;
436         ++src_pos;
437       }
438     } else {
439       memcpy(void_dst, src, src_size);
440     }
441     // Return a non-nullptr pointer to the converted data as an indicator of
442     // success
443     return void_dst;
444   }
445   return nullptr;
446 }
447 
448 //----------------------------------------------------------------------
449 // Extract a single uint32_t from the data and update the offset pointed to by
450 // "offset_ptr".
451 //
452 // RETURNS the uint32_t that was extracted, or zero on failure.
453 //----------------------------------------------------------------------
454 uint32_t DataExtractor::GetU32(offset_t *offset_ptr) const {
455   uint32_t val = 0;
456   const uint8_t *data = (const uint8_t *)GetData(offset_ptr, sizeof(val));
457   if (data) {
458     if (m_byte_order != endian::InlHostByteOrder()) {
459       val = ReadSwapInt32(data);
460     } else {
461       memcpy(&val, data, 4);
462     }
463   }
464   return val;
465 }
466 
467 //----------------------------------------------------------------------
468 // Extract "count" uint32_t values from the binary data and update the offset
469 // pointed to by "offset_ptr". The extracted data is copied into "dst".
470 //
471 // RETURNS the non-nullptr buffer pointer upon successful extraction of
472 // all the requested bytes, or nullptr when the data is not available in the
473 // buffer due to being out of bounds, or insufficient data.
474 //----------------------------------------------------------------------
475 void *DataExtractor::GetU32(offset_t *offset_ptr, void *void_dst,
476                             uint32_t count) const {
477   const size_t src_size = sizeof(uint32_t) * count;
478   const uint32_t *src = (const uint32_t *)GetData(offset_ptr, src_size);
479   if (src) {
480     if (m_byte_order != endian::InlHostByteOrder()) {
481       uint32_t *dst_pos = (uint32_t *)void_dst;
482       uint32_t *dst_end = dst_pos + count;
483       const uint32_t *src_pos = src;
484       while (dst_pos < dst_end) {
485         *dst_pos = ReadSwapInt32(src_pos);
486         ++dst_pos;
487         ++src_pos;
488       }
489     } else {
490       memcpy(void_dst, src, src_size);
491     }
492     // Return a non-nullptr pointer to the converted data as an indicator of
493     // success
494     return void_dst;
495   }
496   return nullptr;
497 }
498 
499 //----------------------------------------------------------------------
500 // Extract a single uint64_t from the data and update the offset pointed to by
501 // "offset_ptr".
502 //
503 // RETURNS the uint64_t that was extracted, or zero on failure.
504 //----------------------------------------------------------------------
505 uint64_t DataExtractor::GetU64(offset_t *offset_ptr) const {
506   uint64_t val = 0;
507   const uint8_t *data = (const uint8_t *)GetData(offset_ptr, sizeof(val));
508   if (data) {
509     if (m_byte_order != endian::InlHostByteOrder()) {
510       val = ReadSwapInt64(data);
511     } else {
512       memcpy(&val, data, 8);
513     }
514   }
515   return val;
516 }
517 
518 //----------------------------------------------------------------------
519 // GetU64
520 //
521 // Get multiple consecutive 64 bit values. Return true if the entire read
522 // succeeds and increment the offset pointed to by offset_ptr, else return
523 // false and leave the offset pointed to by offset_ptr unchanged.
524 //----------------------------------------------------------------------
525 void *DataExtractor::GetU64(offset_t *offset_ptr, void *void_dst,
526                             uint32_t count) const {
527   const size_t src_size = sizeof(uint64_t) * count;
528   const uint64_t *src = (const uint64_t *)GetData(offset_ptr, src_size);
529   if (src) {
530     if (m_byte_order != endian::InlHostByteOrder()) {
531       uint64_t *dst_pos = (uint64_t *)void_dst;
532       uint64_t *dst_end = dst_pos + count;
533       const uint64_t *src_pos = src;
534       while (dst_pos < dst_end) {
535         *dst_pos = ReadSwapInt64(src_pos);
536         ++dst_pos;
537         ++src_pos;
538       }
539     } else {
540       memcpy(void_dst, src, src_size);
541     }
542     // Return a non-nullptr pointer to the converted data as an indicator of
543     // success
544     return void_dst;
545   }
546   return nullptr;
547 }
548 
549 uint32_t DataExtractor::GetMaxU32(offset_t *offset_ptr,
550                                   size_t byte_size) const {
551   lldbassert(byte_size > 0 && byte_size <= 4 && "GetMaxU32 invalid byte_size!");
552   return GetMaxU64(offset_ptr, byte_size);
553 }
554 
555 uint64_t DataExtractor::GetMaxU64(offset_t *offset_ptr,
556                                   size_t byte_size) const {
557   lldbassert(byte_size > 0 && byte_size <= 8 && "GetMaxU64 invalid byte_size!");
558   switch (byte_size) {
559   case 1:
560     return GetU8(offset_ptr);
561   case 2:
562     return GetU16(offset_ptr);
563   case 4:
564     return GetU32(offset_ptr);
565   case 8:
566     return GetU64(offset_ptr);
567   default: {
568     // General case.
569     const uint8_t *data =
570         static_cast<const uint8_t *>(GetData(offset_ptr, byte_size));
571     if (data == nullptr)
572       return 0;
573     return ReadMaxInt64(data, byte_size, m_byte_order);
574   }
575   }
576   return 0;
577 }
578 
579 uint64_t DataExtractor::GetMaxU64_unchecked(offset_t *offset_ptr,
580                                             size_t byte_size) const {
581   switch (byte_size) {
582   case 1:
583     return GetU8_unchecked(offset_ptr);
584   case 2:
585     return GetU16_unchecked(offset_ptr);
586   case 4:
587     return GetU32_unchecked(offset_ptr);
588   case 8:
589     return GetU64_unchecked(offset_ptr);
590   default: {
591     uint64_t res = ReadMaxInt64(&m_start[*offset_ptr], byte_size, m_byte_order);
592     *offset_ptr += byte_size;
593     return res;
594   }
595   }
596   return 0;
597 }
598 
599 int64_t DataExtractor::GetMaxS64(offset_t *offset_ptr, size_t byte_size) const {
600   uint64_t u64 = GetMaxU64(offset_ptr, byte_size);
601   return llvm::SignExtend64(u64, 8 * byte_size);
602 }
603 
604 uint64_t DataExtractor::GetMaxU64Bitfield(offset_t *offset_ptr, size_t size,
605                                           uint32_t bitfield_bit_size,
606                                           uint32_t bitfield_bit_offset) const {
607   uint64_t uval64 = GetMaxU64(offset_ptr, size);
608   if (bitfield_bit_size > 0) {
609     int32_t lsbcount = bitfield_bit_offset;
610     if (m_byte_order == eByteOrderBig)
611       lsbcount = size * 8 - bitfield_bit_offset - bitfield_bit_size;
612     if (lsbcount > 0)
613       uval64 >>= lsbcount;
614     uint64_t bitfield_mask = ((1ul << bitfield_bit_size) - 1);
615     if (!bitfield_mask && bitfield_bit_offset == 0 && bitfield_bit_size == 64)
616       return uval64;
617     uval64 &= bitfield_mask;
618   }
619   return uval64;
620 }
621 
622 int64_t DataExtractor::GetMaxS64Bitfield(offset_t *offset_ptr, size_t size,
623                                          uint32_t bitfield_bit_size,
624                                          uint32_t bitfield_bit_offset) const {
625   int64_t sval64 = GetMaxS64(offset_ptr, size);
626   if (bitfield_bit_size > 0) {
627     int32_t lsbcount = bitfield_bit_offset;
628     if (m_byte_order == eByteOrderBig)
629       lsbcount = size * 8 - bitfield_bit_offset - bitfield_bit_size;
630     if (lsbcount > 0)
631       sval64 >>= lsbcount;
632     uint64_t bitfield_mask = (((uint64_t)1) << bitfield_bit_size) - 1;
633     sval64 &= bitfield_mask;
634     // sign extend if needed
635     if (sval64 & (((uint64_t)1) << (bitfield_bit_size - 1)))
636       sval64 |= ~bitfield_mask;
637   }
638   return sval64;
639 }
640 
641 float DataExtractor::GetFloat(offset_t *offset_ptr) const {
642   typedef float float_type;
643   float_type val = 0.0;
644   const size_t src_size = sizeof(float_type);
645   const float_type *src = (const float_type *)GetData(offset_ptr, src_size);
646   if (src) {
647     if (m_byte_order != endian::InlHostByteOrder()) {
648       const uint8_t *src_data = (const uint8_t *)src;
649       uint8_t *dst_data = (uint8_t *)&val;
650       for (size_t i = 0; i < sizeof(float_type); ++i)
651         dst_data[sizeof(float_type) - 1 - i] = src_data[i];
652     } else {
653       val = *src;
654     }
655   }
656   return val;
657 }
658 
659 double DataExtractor::GetDouble(offset_t *offset_ptr) const {
660   typedef double float_type;
661   float_type val = 0.0;
662   const size_t src_size = sizeof(float_type);
663   const float_type *src = (const float_type *)GetData(offset_ptr, src_size);
664   if (src) {
665     if (m_byte_order != endian::InlHostByteOrder()) {
666       const uint8_t *src_data = (const uint8_t *)src;
667       uint8_t *dst_data = (uint8_t *)&val;
668       for (size_t i = 0; i < sizeof(float_type); ++i)
669         dst_data[sizeof(float_type) - 1 - i] = src_data[i];
670     } else {
671       val = *src;
672     }
673   }
674   return val;
675 }
676 
677 long double DataExtractor::GetLongDouble(offset_t *offset_ptr) const {
678   long double val = 0.0;
679 #if defined(__i386__) || defined(__amd64__) || defined(__x86_64__) ||          \
680     defined(_M_IX86) || defined(_M_IA64) || defined(_M_X64)
681   *offset_ptr += CopyByteOrderedData(*offset_ptr, 10, &val, sizeof(val),
682                                      endian::InlHostByteOrder());
683 #else
684   *offset_ptr += CopyByteOrderedData(*offset_ptr, sizeof(val), &val,
685                                      sizeof(val), endian::InlHostByteOrder());
686 #endif
687   return val;
688 }
689 
690 //------------------------------------------------------------------
691 // Extract a single address from the data and update the offset pointed to by
692 // "offset_ptr". The size of the extracted address comes from the
693 // "this->m_addr_size" member variable and should be set correctly prior to
694 // extracting any address values.
695 //
696 // RETURNS the address that was extracted, or zero on failure.
697 //------------------------------------------------------------------
698 uint64_t DataExtractor::GetAddress(offset_t *offset_ptr) const {
699   assert(m_addr_size == 4 || m_addr_size == 8);
700   return GetMaxU64(offset_ptr, m_addr_size);
701 }
702 
703 uint64_t DataExtractor::GetAddress_unchecked(offset_t *offset_ptr) const {
704   assert(m_addr_size == 4 || m_addr_size == 8);
705   return GetMaxU64_unchecked(offset_ptr, m_addr_size);
706 }
707 
708 //------------------------------------------------------------------
709 // Extract a single pointer from the data and update the offset pointed to by
710 // "offset_ptr". The size of the extracted pointer comes from the
711 // "this->m_addr_size" member variable and should be set correctly prior to
712 // extracting any pointer values.
713 //
714 // RETURNS the pointer that was extracted, or zero on failure.
715 //------------------------------------------------------------------
716 uint64_t DataExtractor::GetPointer(offset_t *offset_ptr) const {
717   assert(m_addr_size == 4 || m_addr_size == 8);
718   return GetMaxU64(offset_ptr, m_addr_size);
719 }
720 
721 size_t DataExtractor::ExtractBytes(offset_t offset, offset_t length,
722                                    ByteOrder dst_byte_order, void *dst) const {
723   const uint8_t *src = PeekData(offset, length);
724   if (src) {
725     if (dst_byte_order != GetByteOrder()) {
726       // Validate that only a word- or register-sized dst is byte swapped
727       assert(length == 1 || length == 2 || length == 4 || length == 8 ||
728              length == 10 || length == 16 || length == 32);
729 
730       for (uint32_t i = 0; i < length; ++i)
731         ((uint8_t *)dst)[i] = src[length - i - 1];
732     } else
733       ::memcpy(dst, src, length);
734     return length;
735   }
736   return 0;
737 }
738 
739 // Extract data as it exists in target memory
740 lldb::offset_t DataExtractor::CopyData(offset_t offset, offset_t length,
741                                        void *dst) const {
742   const uint8_t *src = PeekData(offset, length);
743   if (src) {
744     ::memcpy(dst, src, length);
745     return length;
746   }
747   return 0;
748 }
749 
750 // Extract data and swap if needed when doing the copy
751 lldb::offset_t
752 DataExtractor::CopyByteOrderedData(offset_t src_offset, offset_t src_len,
753                                    void *dst_void_ptr, offset_t dst_len,
754                                    ByteOrder dst_byte_order) const {
755   // Validate the source info
756   if (!ValidOffsetForDataOfSize(src_offset, src_len))
757     assert(ValidOffsetForDataOfSize(src_offset, src_len));
758   assert(src_len > 0);
759   assert(m_byte_order == eByteOrderBig || m_byte_order == eByteOrderLittle);
760 
761   // Validate the destination info
762   assert(dst_void_ptr != nullptr);
763   assert(dst_len > 0);
764   assert(dst_byte_order == eByteOrderBig || dst_byte_order == eByteOrderLittle);
765 
766   // Validate that only a word- or register-sized dst is byte swapped
767   assert(dst_byte_order == m_byte_order || dst_len == 1 || dst_len == 2 ||
768          dst_len == 4 || dst_len == 8 || dst_len == 10 || dst_len == 16 ||
769          dst_len == 32);
770 
771   // Must have valid byte orders set in this object and for destination
772   if (!(dst_byte_order == eByteOrderBig ||
773         dst_byte_order == eByteOrderLittle) ||
774       !(m_byte_order == eByteOrderBig || m_byte_order == eByteOrderLittle))
775     return 0;
776 
777   uint8_t *dst = (uint8_t *)dst_void_ptr;
778   const uint8_t *src = (const uint8_t *)PeekData(src_offset, src_len);
779   if (src) {
780     if (dst_len >= src_len) {
781       // We are copying the entire value from src into dst. Calculate how many,
782       // if any, zeroes we need for the most significant bytes if "dst_len" is
783       // greater than "src_len"...
784       const size_t num_zeroes = dst_len - src_len;
785       if (dst_byte_order == eByteOrderBig) {
786         // Big endian, so we lead with zeroes...
787         if (num_zeroes > 0)
788           ::memset(dst, 0, num_zeroes);
789         // Then either copy or swap the rest
790         if (m_byte_order == eByteOrderBig) {
791           ::memcpy(dst + num_zeroes, src, src_len);
792         } else {
793           for (uint32_t i = 0; i < src_len; ++i)
794             dst[i + num_zeroes] = src[src_len - 1 - i];
795         }
796       } else {
797         // Little endian destination, so we lead the value bytes
798         if (m_byte_order == eByteOrderBig) {
799           for (uint32_t i = 0; i < src_len; ++i)
800             dst[i] = src[src_len - 1 - i];
801         } else {
802           ::memcpy(dst, src, src_len);
803         }
804         // And zero the rest...
805         if (num_zeroes > 0)
806           ::memset(dst + src_len, 0, num_zeroes);
807       }
808       return src_len;
809     } else {
810       // We are only copying some of the value from src into dst..
811 
812       if (dst_byte_order == eByteOrderBig) {
813         // Big endian dst
814         if (m_byte_order == eByteOrderBig) {
815           // Big endian dst, with big endian src
816           ::memcpy(dst, src + (src_len - dst_len), dst_len);
817         } else {
818           // Big endian dst, with little endian src
819           for (uint32_t i = 0; i < dst_len; ++i)
820             dst[i] = src[dst_len - 1 - i];
821         }
822       } else {
823         // Little endian dst
824         if (m_byte_order == eByteOrderBig) {
825           // Little endian dst, with big endian src
826           for (uint32_t i = 0; i < dst_len; ++i)
827             dst[i] = src[src_len - 1 - i];
828         } else {
829           // Little endian dst, with big endian src
830           ::memcpy(dst, src, dst_len);
831         }
832       }
833       return dst_len;
834     }
835   }
836   return 0;
837 }
838 
839 //----------------------------------------------------------------------
840 // Extracts a variable length NULL terminated C string from the data at the
841 // offset pointed to by "offset_ptr".  The "offset_ptr" will be updated with
842 // the offset of the byte that follows the NULL terminator byte.
843 //
844 // If the offset pointed to by "offset_ptr" is out of bounds, or if "length" is
845 // non-zero and there aren't enough available bytes, nullptr will be returned
846 // and "offset_ptr" will not be updated.
847 //----------------------------------------------------------------------
848 const char *DataExtractor::GetCStr(offset_t *offset_ptr) const {
849   const char *cstr = (const char *)PeekData(*offset_ptr, 1);
850   if (cstr) {
851     const char *cstr_end = cstr;
852     const char *end = (const char *)m_end;
853     while (cstr_end < end && *cstr_end)
854       ++cstr_end;
855 
856     // Now we are either at the end of the data or we point to the
857     // NULL C string terminator with cstr_end...
858     if (*cstr_end == '\0') {
859       // Advance the offset with one extra byte for the NULL terminator
860       *offset_ptr += (cstr_end - cstr + 1);
861       return cstr;
862     }
863 
864     // We reached the end of the data without finding a NULL C string
865     // terminator. Fall through and return nullptr otherwise anyone that would
866     // have used the result as a C string can wander into unknown memory...
867   }
868   return nullptr;
869 }
870 
871 //----------------------------------------------------------------------
872 // Extracts a NULL terminated C string from the fixed length field of length
873 // "len" at the offset pointed to by "offset_ptr". The "offset_ptr" will be
874 // updated with the offset of the byte that follows the fixed length field.
875 //
876 // If the offset pointed to by "offset_ptr" is out of bounds, or if the offset
877 // plus the length of the field is out of bounds, or if the field does not
878 // contain a NULL terminator byte, nullptr will be returned and "offset_ptr"
879 // will not be updated.
880 //----------------------------------------------------------------------
881 const char *DataExtractor::GetCStr(offset_t *offset_ptr, offset_t len) const {
882   const char *cstr = (const char *)PeekData(*offset_ptr, len);
883   if (cstr != nullptr) {
884     if (memchr(cstr, '\0', len) == nullptr) {
885       return nullptr;
886     }
887     *offset_ptr += len;
888     return cstr;
889   }
890   return nullptr;
891 }
892 
893 //------------------------------------------------------------------
894 // Peeks at a string in the contained data. No verification is done to make
895 // sure the entire string lies within the bounds of this object's data, only
896 // "offset" is verified to be a valid offset.
897 //
898 // Returns a valid C string pointer if "offset" is a valid offset in this
899 // object's data, else nullptr is returned.
900 //------------------------------------------------------------------
901 const char *DataExtractor::PeekCStr(offset_t offset) const {
902   return (const char *)PeekData(offset, 1);
903 }
904 
905 //----------------------------------------------------------------------
906 // Extracts an unsigned LEB128 number from this object's data starting at the
907 // offset pointed to by "offset_ptr". The offset pointed to by "offset_ptr"
908 // will be updated with the offset of the byte following the last extracted
909 // byte.
910 //
911 // Returned the extracted integer value.
912 //----------------------------------------------------------------------
913 uint64_t DataExtractor::GetULEB128(offset_t *offset_ptr) const {
914   const uint8_t *src = (const uint8_t *)PeekData(*offset_ptr, 1);
915   if (src == nullptr)
916     return 0;
917 
918   const uint8_t *end = m_end;
919 
920   if (src < end) {
921     uint64_t result = *src++;
922     if (result >= 0x80) {
923       result &= 0x7f;
924       int shift = 7;
925       while (src < end) {
926         uint8_t byte = *src++;
927         result |= (uint64_t)(byte & 0x7f) << shift;
928         if ((byte & 0x80) == 0)
929           break;
930         shift += 7;
931       }
932     }
933     *offset_ptr = src - m_start;
934     return result;
935   }
936 
937   return 0;
938 }
939 
940 //----------------------------------------------------------------------
941 // Extracts an signed LEB128 number from this object's data starting at the
942 // offset pointed to by "offset_ptr". The offset pointed to by "offset_ptr"
943 // will be updated with the offset of the byte following the last extracted
944 // byte.
945 //
946 // Returned the extracted integer value.
947 //----------------------------------------------------------------------
948 int64_t DataExtractor::GetSLEB128(offset_t *offset_ptr) const {
949   const uint8_t *src = (const uint8_t *)PeekData(*offset_ptr, 1);
950   if (src == nullptr)
951     return 0;
952 
953   const uint8_t *end = m_end;
954 
955   if (src < end) {
956     int64_t result = 0;
957     int shift = 0;
958     int size = sizeof(int64_t) * 8;
959 
960     uint8_t byte = 0;
961     int bytecount = 0;
962 
963     while (src < end) {
964       bytecount++;
965       byte = *src++;
966       result |= (int64_t)(byte & 0x7f) << shift;
967       shift += 7;
968       if ((byte & 0x80) == 0)
969         break;
970     }
971 
972     // Sign bit of byte is 2nd high order bit (0x40)
973     if (shift < size && (byte & 0x40))
974       result |= -(1 << shift);
975 
976     *offset_ptr += bytecount;
977     return result;
978   }
979   return 0;
980 }
981 
982 //----------------------------------------------------------------------
983 // Skips a ULEB128 number (signed or unsigned) from this object's data starting
984 // at the offset pointed to by "offset_ptr". The offset pointed to by
985 // "offset_ptr" will be updated with the offset of the byte following the last
986 // extracted byte.
987 //
988 // Returns the number of bytes consumed during the extraction.
989 //----------------------------------------------------------------------
990 uint32_t DataExtractor::Skip_LEB128(offset_t *offset_ptr) const {
991   uint32_t bytes_consumed = 0;
992   const uint8_t *src = (const uint8_t *)PeekData(*offset_ptr, 1);
993   if (src == nullptr)
994     return 0;
995 
996   const uint8_t *end = m_end;
997 
998   if (src < end) {
999     const uint8_t *src_pos = src;
1000     while ((src_pos < end) && (*src_pos++ & 0x80))
1001       ++bytes_consumed;
1002     *offset_ptr += src_pos - src;
1003   }
1004   return bytes_consumed;
1005 }
1006 
1007 //----------------------------------------------------------------------
1008 // Dumps bytes from this object's data to the stream "s" starting
1009 // "start_offset" bytes into this data, and ending with the byte before
1010 // "end_offset". "base_addr" will be added to the offset into the dumped data
1011 // when showing the offset into the data in the output information.
1012 // "num_per_line" objects of type "type" will be dumped with the option to
1013 // override the format for each object with "type_format". "type_format" is a
1014 // printf style formatting string. If "type_format" is nullptr, then an
1015 // appropriate format string will be used for the supplied "type". If the
1016 // stream "s" is nullptr, then the output will be send to Log().
1017 //----------------------------------------------------------------------
1018 lldb::offset_t DataExtractor::PutToLog(Log *log, offset_t start_offset,
1019                                        offset_t length, uint64_t base_addr,
1020                                        uint32_t num_per_line,
1021                                        DataExtractor::Type type,
1022                                        const char *format) const {
1023   if (log == nullptr)
1024     return start_offset;
1025 
1026   offset_t offset;
1027   offset_t end_offset;
1028   uint32_t count;
1029   StreamString sstr;
1030   for (offset = start_offset, end_offset = offset + length, count = 0;
1031        ValidOffset(offset) && offset < end_offset; ++count) {
1032     if ((count % num_per_line) == 0) {
1033       // Print out any previous string
1034       if (sstr.GetSize() > 0) {
1035         log->PutString(sstr.GetString());
1036         sstr.Clear();
1037       }
1038       // Reset string offset and fill the current line string with address:
1039       if (base_addr != LLDB_INVALID_ADDRESS)
1040         sstr.Printf("0x%8.8" PRIx64 ":",
1041                     (uint64_t)(base_addr + (offset - start_offset)));
1042     }
1043 
1044     switch (type) {
1045     case TypeUInt8:
1046       sstr.Printf(format ? format : " %2.2x", GetU8(&offset));
1047       break;
1048     case TypeChar: {
1049       char ch = GetU8(&offset);
1050       sstr.Printf(format ? format : " %c", isprint(ch) ? ch : ' ');
1051     } break;
1052     case TypeUInt16:
1053       sstr.Printf(format ? format : " %4.4x", GetU16(&offset));
1054       break;
1055     case TypeUInt32:
1056       sstr.Printf(format ? format : " %8.8x", GetU32(&offset));
1057       break;
1058     case TypeUInt64:
1059       sstr.Printf(format ? format : " %16.16" PRIx64, GetU64(&offset));
1060       break;
1061     case TypePointer:
1062       sstr.Printf(format ? format : " 0x%" PRIx64, GetAddress(&offset));
1063       break;
1064     case TypeULEB128:
1065       sstr.Printf(format ? format : " 0x%" PRIx64, GetULEB128(&offset));
1066       break;
1067     case TypeSLEB128:
1068       sstr.Printf(format ? format : " %" PRId64, GetSLEB128(&offset));
1069       break;
1070     }
1071   }
1072 
1073   if (!sstr.Empty())
1074     log->PutString(sstr.GetString());
1075 
1076   return offset; // Return the offset at which we ended up
1077 }
1078 
1079 size_t DataExtractor::Copy(DataExtractor &dest_data) const {
1080   if (m_data_sp) {
1081     // we can pass along the SP to the data
1082     dest_data.SetData(m_data_sp);
1083   } else {
1084     const uint8_t *base_ptr = m_start;
1085     size_t data_size = GetByteSize();
1086     dest_data.SetData(DataBufferSP(new DataBufferHeap(base_ptr, data_size)));
1087   }
1088   return GetByteSize();
1089 }
1090 
1091 bool DataExtractor::Append(DataExtractor &rhs) {
1092   if (rhs.GetByteOrder() != GetByteOrder())
1093     return false;
1094 
1095   if (rhs.GetByteSize() == 0)
1096     return true;
1097 
1098   if (GetByteSize() == 0)
1099     return (rhs.Copy(*this) > 0);
1100 
1101   size_t bytes = GetByteSize() + rhs.GetByteSize();
1102 
1103   DataBufferHeap *buffer_heap_ptr = nullptr;
1104   DataBufferSP buffer_sp(buffer_heap_ptr = new DataBufferHeap(bytes, 0));
1105 
1106   if (!buffer_sp || buffer_heap_ptr == nullptr)
1107     return false;
1108 
1109   uint8_t *bytes_ptr = buffer_heap_ptr->GetBytes();
1110 
1111   memcpy(bytes_ptr, GetDataStart(), GetByteSize());
1112   memcpy(bytes_ptr + GetByteSize(), rhs.GetDataStart(), rhs.GetByteSize());
1113 
1114   SetData(buffer_sp);
1115 
1116   return true;
1117 }
1118 
1119 bool DataExtractor::Append(void *buf, offset_t length) {
1120   if (buf == nullptr)
1121     return false;
1122 
1123   if (length == 0)
1124     return true;
1125 
1126   size_t bytes = GetByteSize() + length;
1127 
1128   DataBufferHeap *buffer_heap_ptr = nullptr;
1129   DataBufferSP buffer_sp(buffer_heap_ptr = new DataBufferHeap(bytes, 0));
1130 
1131   if (!buffer_sp || buffer_heap_ptr == nullptr)
1132     return false;
1133 
1134   uint8_t *bytes_ptr = buffer_heap_ptr->GetBytes();
1135 
1136   if (GetByteSize() > 0)
1137     memcpy(bytes_ptr, GetDataStart(), GetByteSize());
1138 
1139   memcpy(bytes_ptr + GetByteSize(), buf, length);
1140 
1141   SetData(buffer_sp);
1142 
1143   return true;
1144 }
1145 
1146 void DataExtractor::Checksum(llvm::SmallVectorImpl<uint8_t> &dest,
1147                              uint64_t max_data) {
1148   if (max_data == 0)
1149     max_data = GetByteSize();
1150   else
1151     max_data = std::min(max_data, GetByteSize());
1152 
1153   llvm::MD5 md5;
1154 
1155   const llvm::ArrayRef<uint8_t> data(GetDataStart(), max_data);
1156   md5.update(data);
1157 
1158   llvm::MD5::MD5Result result;
1159   md5.final(result);
1160 
1161   dest.clear();
1162   dest.append(result.Bytes.begin(), result.Bytes.end());
1163 }
1164