dex_file.cc revision 4fa0bcd2142793e1f105b24b658de3635652b957 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "dex_file.h"
18
19#include <fcntl.h>
20#include <limits.h>
21#include <stdio.h>
22#include <stdlib.h>
23#include <string.h>
24#include <sys/file.h>
25#include <sys/stat.h>
26
27#include "base/logging.h"
28#include "base/stringprintf.h"
29#include "class_linker.h"
30#include "dex_file-inl.h"
31#include "dex_file_verifier.h"
32#include "globals.h"
33#include "leb128.h"
34#include "mirror/art_field-inl.h"
35#include "mirror/art_method-inl.h"
36#include "mirror/string.h"
37#include "os.h"
38#include "safe_map.h"
39#include "ScopedFd.h"
40#include "sirt_ref.h"
41#include "thread.h"
42#include "UniquePtr.h"
43#include "utf-inl.h"
44#include "utils.h"
45#include "well_known_classes.h"
46#include "zip_archive.h"
47
48namespace art {
49
50const byte DexFile::kDexMagic[] = { 'd', 'e', 'x', '\n' };
51const byte DexFile::kDexMagicVersion[] = { '0', '3', '5', '\0' };
52
53DexFile::ClassPathEntry DexFile::FindInClassPath(const char* descriptor,
54                                                 const ClassPath& class_path) {
55  for (size_t i = 0; i != class_path.size(); ++i) {
56    const DexFile* dex_file = class_path[i];
57    const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor);
58    if (dex_class_def != NULL) {
59      return ClassPathEntry(dex_file, dex_class_def);
60    }
61  }
62  // TODO: remove reinterpret_cast when issue with -std=gnu++0x host issue resolved
63  return ClassPathEntry(reinterpret_cast<const DexFile*>(NULL),
64                        reinterpret_cast<const DexFile::ClassDef*>(NULL));
65}
66
67static int OpenAndReadMagic(const char* filename, uint32_t* magic, std::string* error_msg) {
68  CHECK(magic != NULL);
69  ScopedFd fd(open(filename, O_RDONLY, 0));
70  if (fd.get() == -1) {
71    *error_msg = StringPrintf("Unable to open '%s' : %s", filename, strerror(errno));
72    return -1;
73  }
74  int n = TEMP_FAILURE_RETRY(read(fd.get(), magic, sizeof(*magic)));
75  if (n != sizeof(*magic)) {
76    *error_msg = StringPrintf("Failed to find magic in '%s'", filename);
77    return -1;
78  }
79  if (lseek(fd.get(), 0, SEEK_SET) != 0) {
80    *error_msg = StringPrintf("Failed to seek to beginning of file '%s' : %s", filename,
81                              strerror(errno));
82    return -1;
83  }
84  return fd.release();
85}
86
87bool DexFile::GetChecksum(const char* filename, uint32_t* checksum, std::string* error_msg) {
88  CHECK(checksum != NULL);
89  uint32_t magic;
90  ScopedFd fd(OpenAndReadMagic(filename, &magic, error_msg));
91  if (fd.get() == -1) {
92    DCHECK(!error_msg->empty());
93    return false;
94  }
95  if (IsZipMagic(magic)) {
96    UniquePtr<ZipArchive> zip_archive(ZipArchive::OpenFromFd(fd.release(), filename, error_msg));
97    if (zip_archive.get() == NULL) {
98      *error_msg = StringPrintf("Failed to open zip archive '%s'", filename);
99      return false;
100    }
101    UniquePtr<ZipEntry> zip_entry(zip_archive->Find(kClassesDex, error_msg));
102    if (zip_entry.get() == NULL) {
103      *error_msg = StringPrintf("Zip archive '%s' doesn't contain %s (error msg: %s)", filename,
104                                kClassesDex, error_msg->c_str());
105      return false;
106    }
107    *checksum = zip_entry->GetCrc32();
108    return true;
109  }
110  if (IsDexMagic(magic)) {
111    UniquePtr<const DexFile> dex_file(DexFile::OpenFile(fd.release(), filename, false, error_msg));
112    if (dex_file.get() == NULL) {
113      return false;
114    }
115    *checksum = dex_file->GetHeader().checksum_;
116    return true;
117  }
118  *error_msg = StringPrintf("Expected valid zip or dex file: '%s'", filename);
119  return false;
120}
121
122const DexFile* DexFile::Open(const char* filename,
123                             const char* location,
124                             std::string* error_msg) {
125  uint32_t magic;
126  ScopedFd fd(OpenAndReadMagic(filename, &magic, error_msg));
127  if (fd.get() == -1) {
128    DCHECK(!error_msg->empty());
129    return NULL;
130  }
131  if (IsZipMagic(magic)) {
132    return DexFile::OpenZip(fd.release(), location, error_msg);
133  }
134  if (IsDexMagic(magic)) {
135    return DexFile::OpenFile(fd.release(), location, true, error_msg);
136  }
137  *error_msg = StringPrintf("Expected valid zip or dex file: '%s'", filename);
138  return nullptr;
139}
140
141int DexFile::GetPermissions() const {
142  if (mem_map_.get() == NULL) {
143    return 0;
144  } else {
145    return mem_map_->GetProtect();
146  }
147}
148
149bool DexFile::IsReadOnly() const {
150  return GetPermissions() == PROT_READ;
151}
152
153bool DexFile::EnableWrite() const {
154  CHECK(IsReadOnly());
155  if (mem_map_.get() == NULL) {
156    return false;
157  } else {
158    return mem_map_->Protect(PROT_READ | PROT_WRITE);
159  }
160}
161
162bool DexFile::DisableWrite() const {
163  CHECK(!IsReadOnly());
164  if (mem_map_.get() == NULL) {
165    return false;
166  } else {
167    return mem_map_->Protect(PROT_READ);
168  }
169}
170
171const DexFile* DexFile::OpenFile(int fd, const char* location, bool verify,
172                                 std::string* error_msg) {
173  CHECK(location != nullptr);
174  UniquePtr<MemMap> map;
175  {
176    ScopedFd delayed_close(fd);
177    struct stat sbuf;
178    memset(&sbuf, 0, sizeof(sbuf));
179    if (fstat(fd, &sbuf) == -1) {
180      *error_msg = StringPrintf("DexFile: fstat '%s' failed: %s", location, strerror(errno));
181      return nullptr;
182    }
183    if (S_ISDIR(sbuf.st_mode)) {
184      *error_msg = StringPrintf("Attempt to mmap directory '%s'", location);
185      return nullptr;
186    }
187    size_t length = sbuf.st_size;
188    map.reset(MemMap::MapFile(length, PROT_READ, MAP_PRIVATE, fd, 0, location, error_msg));
189    if (map.get() == nullptr) {
190      DCHECK(!error_msg->empty());
191      return nullptr;
192    }
193  }
194
195  if (map->Size() < sizeof(DexFile::Header)) {
196    *error_msg = StringPrintf(
197        "DexFile: failed to open dex file '%s' that is too short to have a header", location);
198    return nullptr;
199  }
200
201  const Header* dex_header = reinterpret_cast<const Header*>(map->Begin());
202
203  const DexFile* dex_file = OpenMemory(location, dex_header->checksum_, map.release(), error_msg);
204  if (dex_file == nullptr) {
205    *error_msg = StringPrintf("Failed to open dex file '%s' from memory: %s", location,
206                              error_msg->c_str());
207    return nullptr;
208  }
209
210  if (verify && !DexFileVerifier::Verify(dex_file, dex_file->Begin(), dex_file->Size(), location,
211                                         error_msg)) {
212    return nullptr;
213  }
214
215  return dex_file;
216}
217
218const char* DexFile::kClassesDex = "classes.dex";
219
220const DexFile* DexFile::OpenZip(int fd, const std::string& location, std::string* error_msg) {
221  UniquePtr<ZipArchive> zip_archive(ZipArchive::OpenFromFd(fd, location.c_str(), error_msg));
222  if (zip_archive.get() == nullptr) {
223    DCHECK(!error_msg->empty());
224    return nullptr;
225  }
226  return DexFile::Open(*zip_archive, location, error_msg);
227}
228
229const DexFile* DexFile::OpenMemory(const std::string& location,
230                                   uint32_t location_checksum,
231                                   MemMap* mem_map,
232                                   std::string* error_msg) {
233  return OpenMemory(mem_map->Begin(),
234                    mem_map->Size(),
235                    location,
236                    location_checksum,
237                    mem_map,
238                    error_msg);
239}
240
241const DexFile* DexFile::Open(const ZipArchive& zip_archive, const std::string& location,
242                             std::string* error_msg) {
243  CHECK(!location.empty());
244  UniquePtr<ZipEntry> zip_entry(zip_archive.Find(kClassesDex, error_msg));
245  if (zip_entry.get() == NULL) {
246    return nullptr;
247  }
248  UniquePtr<MemMap> map(zip_entry->ExtractToMemMap(kClassesDex, error_msg));
249  if (map.get() == NULL) {
250    *error_msg = StringPrintf("Failed to extract '%s' from '%s': %s", kClassesDex, location.c_str(),
251                              error_msg->c_str());
252    return nullptr;
253  }
254  UniquePtr<const DexFile> dex_file(OpenMemory(location, zip_entry->GetCrc32(), map.release(),
255                                               error_msg));
256  if (dex_file.get() == nullptr) {
257    *error_msg = StringPrintf("Failed to open dex file '%s' from memory: %s", location.c_str(),
258                              error_msg->c_str());
259    return nullptr;
260  }
261  if (!DexFileVerifier::Verify(dex_file.get(), dex_file->Begin(), dex_file->Size(),
262                               location.c_str(), error_msg)) {
263    return nullptr;
264  }
265  if (!dex_file->DisableWrite()) {
266    *error_msg = StringPrintf("Failed to make dex file '%s' read only", location.c_str());
267    return nullptr;
268  }
269  CHECK(dex_file->IsReadOnly()) << location;
270  return dex_file.release();
271}
272
273const DexFile* DexFile::OpenMemory(const byte* base,
274                                   size_t size,
275                                   const std::string& location,
276                                   uint32_t location_checksum,
277                                   MemMap* mem_map, std::string* error_msg) {
278  CHECK_ALIGNED(base, 4);  // various dex file structures must be word aligned
279  UniquePtr<DexFile> dex_file(new DexFile(base, size, location, location_checksum, mem_map));
280  if (!dex_file->Init(error_msg)) {
281    return nullptr;
282  } else {
283    return dex_file.release();
284  }
285}
286
287DexFile::~DexFile() {
288  // We don't call DeleteGlobalRef on dex_object_ because we're only called by DestroyJavaVM, and
289  // that's only called after DetachCurrentThread, which means there's no JNIEnv. We could
290  // re-attach, but cleaning up these global references is not obviously useful. It's not as if
291  // the global reference table is otherwise empty!
292}
293
294bool DexFile::Init(std::string* error_msg) {
295  InitMembers();
296  if (!CheckMagicAndVersion(error_msg)) {
297    return false;
298  }
299  return true;
300}
301
302void DexFile::InitMembers() {
303  const byte* b = begin_;
304  header_ = reinterpret_cast<const Header*>(b);
305  const Header* h = header_;
306  string_ids_ = reinterpret_cast<const StringId*>(b + h->string_ids_off_);
307  type_ids_ = reinterpret_cast<const TypeId*>(b + h->type_ids_off_);
308  field_ids_ = reinterpret_cast<const FieldId*>(b + h->field_ids_off_);
309  method_ids_ = reinterpret_cast<const MethodId*>(b + h->method_ids_off_);
310  proto_ids_ = reinterpret_cast<const ProtoId*>(b + h->proto_ids_off_);
311  class_defs_ = reinterpret_cast<const ClassDef*>(b + h->class_defs_off_);
312}
313
314bool DexFile::CheckMagicAndVersion(std::string* error_msg) const {
315  CHECK(header_->magic_ != NULL) << GetLocation();
316  if (!IsMagicValid(header_->magic_)) {
317    std::ostringstream oss;
318    oss << "Unrecognized magic number in "  << GetLocation() << ":"
319            << " " << header_->magic_[0]
320            << " " << header_->magic_[1]
321            << " " << header_->magic_[2]
322            << " " << header_->magic_[3];
323    *error_msg = oss.str();
324    return false;
325  }
326  if (!IsVersionValid(header_->magic_)) {
327    std::ostringstream oss;
328    oss << "Unrecognized version number in "  << GetLocation() << ":"
329            << " " << header_->magic_[4]
330            << " " << header_->magic_[5]
331            << " " << header_->magic_[6]
332            << " " << header_->magic_[7];
333    *error_msg = oss.str();
334    return false;
335  }
336  return true;
337}
338
339bool DexFile::IsMagicValid(const byte* magic) {
340  return (memcmp(magic, kDexMagic, sizeof(kDexMagic)) == 0);
341}
342
343bool DexFile::IsVersionValid(const byte* magic) {
344  const byte* version = &magic[sizeof(kDexMagic)];
345  return (memcmp(version, kDexMagicVersion, sizeof(kDexMagicVersion)) == 0);
346}
347
348uint32_t DexFile::GetVersion() const {
349  const char* version = reinterpret_cast<const char*>(&GetHeader().magic_[sizeof(kDexMagic)]);
350  return atoi(version);
351}
352
353const DexFile::ClassDef* DexFile::FindClassDef(const char* descriptor) const {
354  size_t num_class_defs = NumClassDefs();
355  if (num_class_defs == 0) {
356    return NULL;
357  }
358  const StringId* string_id = FindStringId(descriptor);
359  if (string_id == NULL) {
360    return NULL;
361  }
362  const TypeId* type_id = FindTypeId(GetIndexForStringId(*string_id));
363  if (type_id == NULL) {
364    return NULL;
365  }
366  uint16_t type_idx = GetIndexForTypeId(*type_id);
367  for (size_t i = 0; i < num_class_defs; ++i) {
368    const ClassDef& class_def = GetClassDef(i);
369    if (class_def.class_idx_ == type_idx) {
370      return &class_def;
371    }
372  }
373  return NULL;
374}
375
376const DexFile::ClassDef* DexFile::FindClassDef(uint16_t type_idx) const {
377  size_t num_class_defs = NumClassDefs();
378  for (size_t i = 0; i < num_class_defs; ++i) {
379    const ClassDef& class_def = GetClassDef(i);
380    if (class_def.class_idx_ == type_idx) {
381      return &class_def;
382    }
383  }
384  return NULL;
385}
386
387const DexFile::FieldId* DexFile::FindFieldId(const DexFile::TypeId& declaring_klass,
388                                              const DexFile::StringId& name,
389                                              const DexFile::TypeId& type) const {
390  // Binary search MethodIds knowing that they are sorted by class_idx, name_idx then proto_idx
391  const uint16_t class_idx = GetIndexForTypeId(declaring_klass);
392  const uint32_t name_idx = GetIndexForStringId(name);
393  const uint16_t type_idx = GetIndexForTypeId(type);
394  int32_t lo = 0;
395  int32_t hi = NumFieldIds() - 1;
396  while (hi >= lo) {
397    int32_t mid = (hi + lo) / 2;
398    const DexFile::FieldId& field = GetFieldId(mid);
399    if (class_idx > field.class_idx_) {
400      lo = mid + 1;
401    } else if (class_idx < field.class_idx_) {
402      hi = mid - 1;
403    } else {
404      if (name_idx > field.name_idx_) {
405        lo = mid + 1;
406      } else if (name_idx < field.name_idx_) {
407        hi = mid - 1;
408      } else {
409        if (type_idx > field.type_idx_) {
410          lo = mid + 1;
411        } else if (type_idx < field.type_idx_) {
412          hi = mid - 1;
413        } else {
414          return &field;
415        }
416      }
417    }
418  }
419  return NULL;
420}
421
422const DexFile::MethodId* DexFile::FindMethodId(const DexFile::TypeId& declaring_klass,
423                                               const DexFile::StringId& name,
424                                               const DexFile::ProtoId& signature) const {
425  // Binary search MethodIds knowing that they are sorted by class_idx, name_idx then proto_idx
426  const uint16_t class_idx = GetIndexForTypeId(declaring_klass);
427  const uint32_t name_idx = GetIndexForStringId(name);
428  const uint16_t proto_idx = GetIndexForProtoId(signature);
429  int32_t lo = 0;
430  int32_t hi = NumMethodIds() - 1;
431  while (hi >= lo) {
432    int32_t mid = (hi + lo) / 2;
433    const DexFile::MethodId& method = GetMethodId(mid);
434    if (class_idx > method.class_idx_) {
435      lo = mid + 1;
436    } else if (class_idx < method.class_idx_) {
437      hi = mid - 1;
438    } else {
439      if (name_idx > method.name_idx_) {
440        lo = mid + 1;
441      } else if (name_idx < method.name_idx_) {
442        hi = mid - 1;
443      } else {
444        if (proto_idx > method.proto_idx_) {
445          lo = mid + 1;
446        } else if (proto_idx < method.proto_idx_) {
447          hi = mid - 1;
448        } else {
449          return &method;
450        }
451      }
452    }
453  }
454  return NULL;
455}
456
457const DexFile::StringId* DexFile::FindStringId(const char* string) const {
458  int32_t lo = 0;
459  int32_t hi = NumStringIds() - 1;
460  while (hi >= lo) {
461    int32_t mid = (hi + lo) / 2;
462    const DexFile::StringId& str_id = GetStringId(mid);
463    const char* str = GetStringData(str_id);
464    int compare = CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues(string, str);
465    if (compare > 0) {
466      lo = mid + 1;
467    } else if (compare < 0) {
468      hi = mid - 1;
469    } else {
470      return &str_id;
471    }
472  }
473  return NULL;
474}
475
476const DexFile::StringId* DexFile::FindStringId(const uint16_t* string) const {
477  int32_t lo = 0;
478  int32_t hi = NumStringIds() - 1;
479  while (hi >= lo) {
480    int32_t mid = (hi + lo) / 2;
481    const DexFile::StringId& str_id = GetStringId(mid);
482    const char* str = GetStringData(str_id);
483    int compare = CompareModifiedUtf8ToUtf16AsCodePointValues(str, string);
484    if (compare > 0) {
485      lo = mid + 1;
486    } else if (compare < 0) {
487      hi = mid - 1;
488    } else {
489      return &str_id;
490    }
491  }
492  return NULL;
493}
494
495const DexFile::TypeId* DexFile::FindTypeId(uint32_t string_idx) const {
496  int32_t lo = 0;
497  int32_t hi = NumTypeIds() - 1;
498  while (hi >= lo) {
499    int32_t mid = (hi + lo) / 2;
500    const TypeId& type_id = GetTypeId(mid);
501    if (string_idx > type_id.descriptor_idx_) {
502      lo = mid + 1;
503    } else if (string_idx < type_id.descriptor_idx_) {
504      hi = mid - 1;
505    } else {
506      return &type_id;
507    }
508  }
509  return NULL;
510}
511
512const DexFile::ProtoId* DexFile::FindProtoId(uint16_t return_type_idx,
513                                             const uint16_t* signature_type_idxs,
514                                             uint32_t signature_length) const {
515  int32_t lo = 0;
516  int32_t hi = NumProtoIds() - 1;
517  while (hi >= lo) {
518    int32_t mid = (hi + lo) / 2;
519    const DexFile::ProtoId& proto = GetProtoId(mid);
520    int compare = return_type_idx - proto.return_type_idx_;
521    if (compare == 0) {
522      DexFileParameterIterator it(*this, proto);
523      size_t i = 0;
524      while (it.HasNext() && i < signature_length && compare == 0) {
525        compare = signature_type_idxs[i] - it.GetTypeIdx();
526        it.Next();
527        i++;
528      }
529      if (compare == 0) {
530        if (it.HasNext()) {
531          compare = -1;
532        } else if (i < signature_length) {
533          compare = 1;
534        }
535      }
536    }
537    if (compare > 0) {
538      lo = mid + 1;
539    } else if (compare < 0) {
540      hi = mid - 1;
541    } else {
542      return &proto;
543    }
544  }
545  return NULL;
546}
547
548// Given a signature place the type ids into the given vector
549bool DexFile::CreateTypeList(const StringPiece& signature, uint16_t* return_type_idx,
550                             std::vector<uint16_t>* param_type_idxs) const {
551  if (signature[0] != '(') {
552    return false;
553  }
554  size_t offset = 1;
555  size_t end = signature.size();
556  bool process_return = false;
557  while (offset < end) {
558    size_t start_offset = offset;
559    char c = signature[offset];
560    offset++;
561    if (c == ')') {
562      process_return = true;
563      continue;
564    }
565    while (c == '[') {  // process array prefix
566      if (offset >= end) {  // expect some descriptor following [
567        return false;
568      }
569      c = signature[offset];
570      offset++;
571    }
572    if (c == 'L') {  // process type descriptors
573      do {
574        if (offset >= end) {  // unexpected early termination of descriptor
575          return false;
576        }
577        c = signature[offset];
578        offset++;
579      } while (c != ';');
580    }
581    // TODO: avoid creating a std::string just to get a 0-terminated char array
582    std::string descriptor(signature.data() + start_offset, offset - start_offset);
583    const DexFile::StringId* string_id = FindStringId(descriptor.c_str());
584    if (string_id == NULL) {
585      return false;
586    }
587    const DexFile::TypeId* type_id = FindTypeId(GetIndexForStringId(*string_id));
588    if (type_id == NULL) {
589      return false;
590    }
591    uint16_t type_idx = GetIndexForTypeId(*type_id);
592    if (!process_return) {
593      param_type_idxs->push_back(type_idx);
594    } else {
595      *return_type_idx = type_idx;
596      return offset == end;  // return true if the signature had reached a sensible end
597    }
598  }
599  return false;  // failed to correctly parse return type
600}
601
602const Signature DexFile::CreateSignature(const StringPiece& signature) const {
603  uint16_t return_type_idx;
604  std::vector<uint16_t> param_type_indices;
605  bool success = CreateTypeList(signature, &return_type_idx, &param_type_indices);
606  if (!success) {
607    return Signature::NoSignature();
608  }
609  const ProtoId* proto_id = FindProtoId(return_type_idx, param_type_indices);
610  if (proto_id == NULL) {
611    return Signature::NoSignature();
612  }
613  return Signature(this, *proto_id);
614}
615
616int32_t DexFile::GetLineNumFromPC(const mirror::ArtMethod* method, uint32_t rel_pc) const {
617  // For native method, lineno should be -2 to indicate it is native. Note that
618  // "line number == -2" is how libcore tells from StackTraceElement.
619  if (method->GetCodeItemOffset() == 0) {
620    return -2;
621  }
622
623  const CodeItem* code_item = GetCodeItem(method->GetCodeItemOffset());
624  DCHECK(code_item != NULL) << PrettyMethod(method) << " " << GetLocation();
625
626  // A method with no line number info should return -1
627  LineNumFromPcContext context(rel_pc, -1);
628  DecodeDebugInfo(code_item, method->IsStatic(), method->GetDexMethodIndex(), LineNumForPcCb,
629                  NULL, &context);
630  return context.line_num_;
631}
632
633int32_t DexFile::FindTryItem(const CodeItem &code_item, uint32_t address) {
634  // Note: Signed type is important for max and min.
635  int32_t min = 0;
636  int32_t max = code_item.tries_size_ - 1;
637
638  while (min <= max) {
639    int32_t mid = min + ((max - min) / 2);
640
641    const art::DexFile::TryItem* ti = GetTryItems(code_item, mid);
642    uint32_t start = ti->start_addr_;
643    uint32_t end = start + ti->insn_count_;
644
645    if (address < start) {
646      max = mid - 1;
647    } else if (address >= end) {
648      min = mid + 1;
649    } else {  // We have a winner!
650      return mid;
651    }
652  }
653  // No match.
654  return -1;
655}
656
657int32_t DexFile::FindCatchHandlerOffset(const CodeItem &code_item, uint32_t address) {
658  int32_t try_item = FindTryItem(code_item, address);
659  if (try_item == -1) {
660    return -1;
661  } else {
662    return DexFile::GetTryItems(code_item, try_item)->handler_off_;
663  }
664}
665
666void DexFile::DecodeDebugInfo0(const CodeItem* code_item, bool is_static, uint32_t method_idx,
667                               DexDebugNewPositionCb position_cb, DexDebugNewLocalCb local_cb,
668                               void* context, const byte* stream, LocalInfo* local_in_reg) const {
669  uint32_t line = DecodeUnsignedLeb128(&stream);
670  uint32_t parameters_size = DecodeUnsignedLeb128(&stream);
671  uint16_t arg_reg = code_item->registers_size_ - code_item->ins_size_;
672  uint32_t address = 0;
673  bool need_locals = (local_cb != NULL);
674
675  if (!is_static) {
676    if (need_locals) {
677      const char* descriptor = GetMethodDeclaringClassDescriptor(GetMethodId(method_idx));
678      local_in_reg[arg_reg].name_ = "this";
679      local_in_reg[arg_reg].descriptor_ = descriptor;
680      local_in_reg[arg_reg].signature_ = NULL;
681      local_in_reg[arg_reg].start_address_ = 0;
682      local_in_reg[arg_reg].is_live_ = true;
683    }
684    arg_reg++;
685  }
686
687  DexFileParameterIterator it(*this, GetMethodPrototype(GetMethodId(method_idx)));
688  for (uint32_t i = 0; i < parameters_size && it.HasNext(); ++i, it.Next()) {
689    if (arg_reg >= code_item->registers_size_) {
690      LOG(ERROR) << "invalid stream - arg reg >= reg size (" << arg_reg
691                 << " >= " << code_item->registers_size_ << ") in " << GetLocation();
692      return;
693    }
694    uint32_t id = DecodeUnsignedLeb128P1(&stream);
695    const char* descriptor = it.GetDescriptor();
696    if (need_locals && id != kDexNoIndex) {
697      const char* name = StringDataByIdx(id);
698      local_in_reg[arg_reg].name_ = name;
699      local_in_reg[arg_reg].descriptor_ = descriptor;
700      local_in_reg[arg_reg].signature_ = NULL;
701      local_in_reg[arg_reg].start_address_ = address;
702      local_in_reg[arg_reg].is_live_ = true;
703    }
704    switch (*descriptor) {
705      case 'D':
706      case 'J':
707        arg_reg += 2;
708        break;
709      default:
710        arg_reg += 1;
711        break;
712    }
713  }
714
715  if (it.HasNext()) {
716    LOG(ERROR) << "invalid stream - problem with parameter iterator in " << GetLocation();
717    return;
718  }
719
720  for (;;)  {
721    uint8_t opcode = *stream++;
722    uint16_t reg;
723    uint32_t name_idx;
724    uint32_t descriptor_idx;
725    uint32_t signature_idx = 0;
726
727    switch (opcode) {
728      case DBG_END_SEQUENCE:
729        return;
730
731      case DBG_ADVANCE_PC:
732        address += DecodeUnsignedLeb128(&stream);
733        break;
734
735      case DBG_ADVANCE_LINE:
736        line += DecodeSignedLeb128(&stream);
737        break;
738
739      case DBG_START_LOCAL:
740      case DBG_START_LOCAL_EXTENDED:
741        reg = DecodeUnsignedLeb128(&stream);
742        if (reg > code_item->registers_size_) {
743          LOG(ERROR) << "invalid stream - reg > reg size (" << reg << " > "
744                     << code_item->registers_size_ << ") in " << GetLocation();
745          return;
746        }
747
748        name_idx = DecodeUnsignedLeb128P1(&stream);
749        descriptor_idx = DecodeUnsignedLeb128P1(&stream);
750        if (opcode == DBG_START_LOCAL_EXTENDED) {
751          signature_idx = DecodeUnsignedLeb128P1(&stream);
752        }
753
754        // Emit what was previously there, if anything
755        if (need_locals) {
756          InvokeLocalCbIfLive(context, reg, address, local_in_reg, local_cb);
757
758          local_in_reg[reg].name_ = StringDataByIdx(name_idx);
759          local_in_reg[reg].descriptor_ = StringByTypeIdx(descriptor_idx);
760          if (opcode == DBG_START_LOCAL_EXTENDED) {
761            local_in_reg[reg].signature_ = StringDataByIdx(signature_idx);
762          }
763          local_in_reg[reg].start_address_ = address;
764          local_in_reg[reg].is_live_ = true;
765        }
766        break;
767
768      case DBG_END_LOCAL:
769        reg = DecodeUnsignedLeb128(&stream);
770        if (reg > code_item->registers_size_) {
771          LOG(ERROR) << "invalid stream - reg > reg size (" << reg << " > "
772                     << code_item->registers_size_ << ") in " << GetLocation();
773          return;
774        }
775
776        if (need_locals) {
777          InvokeLocalCbIfLive(context, reg, address, local_in_reg, local_cb);
778          local_in_reg[reg].is_live_ = false;
779        }
780        break;
781
782      case DBG_RESTART_LOCAL:
783        reg = DecodeUnsignedLeb128(&stream);
784        if (reg > code_item->registers_size_) {
785          LOG(ERROR) << "invalid stream - reg > reg size (" << reg << " > "
786                     << code_item->registers_size_ << ") in " << GetLocation();
787          return;
788        }
789
790        if (need_locals) {
791          if (local_in_reg[reg].name_ == NULL || local_in_reg[reg].descriptor_ == NULL) {
792            LOG(ERROR) << "invalid stream - no name or descriptor in " << GetLocation();
793            return;
794          }
795
796          // If the register is live, the "restart" is superfluous,
797          // and we don't want to mess with the existing start address.
798          if (!local_in_reg[reg].is_live_) {
799            local_in_reg[reg].start_address_ = address;
800            local_in_reg[reg].is_live_ = true;
801          }
802        }
803        break;
804
805      case DBG_SET_PROLOGUE_END:
806      case DBG_SET_EPILOGUE_BEGIN:
807      case DBG_SET_FILE:
808        break;
809
810      default: {
811        int adjopcode = opcode - DBG_FIRST_SPECIAL;
812
813        address += adjopcode / DBG_LINE_RANGE;
814        line += DBG_LINE_BASE + (adjopcode % DBG_LINE_RANGE);
815
816        if (position_cb != NULL) {
817          if (position_cb(context, address, line)) {
818            // early exit
819            return;
820          }
821        }
822        break;
823      }
824    }
825  }
826}
827
828void DexFile::DecodeDebugInfo(const CodeItem* code_item, bool is_static, uint32_t method_idx,
829                              DexDebugNewPositionCb position_cb, DexDebugNewLocalCb local_cb,
830                              void* context) const {
831  const byte* stream = GetDebugInfoStream(code_item);
832  UniquePtr<LocalInfo[]> local_in_reg(local_cb != NULL ?
833                                      new LocalInfo[code_item->registers_size_] :
834                                      NULL);
835  if (stream != NULL) {
836    DecodeDebugInfo0(code_item, is_static, method_idx, position_cb, local_cb, context, stream, &local_in_reg[0]);
837  }
838  for (int reg = 0; reg < code_item->registers_size_; reg++) {
839    InvokeLocalCbIfLive(context, reg, code_item->insns_size_in_code_units_, &local_in_reg[0], local_cb);
840  }
841}
842
843bool DexFile::LineNumForPcCb(void* raw_context, uint32_t address, uint32_t line_num) {
844  LineNumFromPcContext* context = reinterpret_cast<LineNumFromPcContext*>(raw_context);
845
846  // We know that this callback will be called in
847  // ascending address order, so keep going until we find
848  // a match or we've just gone past it.
849  if (address > context->address_) {
850    // The line number from the previous positions callback
851    // wil be the final result.
852    return true;
853  } else {
854    context->line_num_ = line_num;
855    return address == context->address_;
856  }
857}
858
859std::string Signature::ToString() const {
860  if (dex_file_ == nullptr) {
861    CHECK(proto_id_ == nullptr);
862    return "<no signature>";
863  }
864  const DexFile::TypeList* params = dex_file_->GetProtoParameters(*proto_id_);
865  std::string result;
866  if (params == nullptr) {
867    result += "()";
868  } else {
869    result += "(";
870    for (uint32_t i = 0; i < params->Size(); ++i) {
871      result += dex_file_->StringByTypeIdx(params->GetTypeItem(i).type_idx_);
872    }
873    result += ")";
874  }
875  result += dex_file_->StringByTypeIdx(proto_id_->return_type_idx_);
876  return result;
877}
878
879bool Signature::operator==(const StringPiece& rhs) const {
880  if (dex_file_ == nullptr) {
881    return false;
882  }
883  StringPiece tail(rhs);
884  if (!tail.starts_with("(")) {
885    return false;  // Invalid signature
886  }
887  tail.remove_prefix(1);  // "(";
888  const DexFile::TypeList* params = dex_file_->GetProtoParameters(*proto_id_);
889  if (params != nullptr) {
890    for (uint32_t i = 0; i < params->Size(); ++i) {
891      StringPiece param(dex_file_->StringByTypeIdx(params->GetTypeItem(i).type_idx_));
892      if (!tail.starts_with(param)) {
893        return false;
894      }
895      tail.remove_prefix(param.length());
896    }
897  }
898  if (!tail.starts_with(")")) {
899    return false;
900  }
901  tail.remove_prefix(1);  // ")";
902  return tail == dex_file_->StringByTypeIdx(proto_id_->return_type_idx_);
903}
904
905std::ostream& operator<<(std::ostream& os, const Signature& sig) {
906  return os << sig.ToString();
907}
908
909// Decodes the header section from the class data bytes.
910void ClassDataItemIterator::ReadClassDataHeader() {
911  CHECK(ptr_pos_ != NULL);
912  header_.static_fields_size_ = DecodeUnsignedLeb128(&ptr_pos_);
913  header_.instance_fields_size_ = DecodeUnsignedLeb128(&ptr_pos_);
914  header_.direct_methods_size_ = DecodeUnsignedLeb128(&ptr_pos_);
915  header_.virtual_methods_size_ = DecodeUnsignedLeb128(&ptr_pos_);
916}
917
918void ClassDataItemIterator::ReadClassDataField() {
919  field_.field_idx_delta_ = DecodeUnsignedLeb128(&ptr_pos_);
920  field_.access_flags_ = DecodeUnsignedLeb128(&ptr_pos_);
921  if (last_idx_ != 0 && field_.field_idx_delta_ == 0) {
922    LOG(WARNING) << "Duplicate field " << PrettyField(GetMemberIndex(), dex_file_)
923                 << " in " << dex_file_.GetLocation();
924  }
925}
926
927void ClassDataItemIterator::ReadClassDataMethod() {
928  method_.method_idx_delta_ = DecodeUnsignedLeb128(&ptr_pos_);
929  method_.access_flags_ = DecodeUnsignedLeb128(&ptr_pos_);
930  method_.code_off_ = DecodeUnsignedLeb128(&ptr_pos_);
931  if (last_idx_ != 0 && method_.method_idx_delta_ == 0) {
932    LOG(WARNING) << "Duplicate method " << PrettyMethod(GetMemberIndex(), dex_file_)
933                 << " in " << dex_file_.GetLocation();
934  }
935}
936
937// Read a signed integer.  "zwidth" is the zero-based byte count.
938static int32_t ReadSignedInt(const byte* ptr, int zwidth) {
939  int32_t val = 0;
940  for (int i = zwidth; i >= 0; --i) {
941    val = ((uint32_t)val >> 8) | (((int32_t)*ptr++) << 24);
942  }
943  val >>= (3 - zwidth) * 8;
944  return val;
945}
946
947// Read an unsigned integer.  "zwidth" is the zero-based byte count,
948// "fill_on_right" indicates which side we want to zero-fill from.
949static uint32_t ReadUnsignedInt(const byte* ptr, int zwidth, bool fill_on_right) {
950  uint32_t val = 0;
951  if (!fill_on_right) {
952    for (int i = zwidth; i >= 0; --i) {
953      val = (val >> 8) | (((uint32_t)*ptr++) << 24);
954    }
955    val >>= (3 - zwidth) * 8;
956  } else {
957    for (int i = zwidth; i >= 0; --i) {
958      val = (val >> 8) | (((uint32_t)*ptr++) << 24);
959    }
960  }
961  return val;
962}
963
964// Read a signed long.  "zwidth" is the zero-based byte count.
965static int64_t ReadSignedLong(const byte* ptr, int zwidth) {
966  int64_t val = 0;
967  for (int i = zwidth; i >= 0; --i) {
968    val = ((uint64_t)val >> 8) | (((int64_t)*ptr++) << 56);
969  }
970  val >>= (7 - zwidth) * 8;
971  return val;
972}
973
974// Read an unsigned long.  "zwidth" is the zero-based byte count,
975// "fill_on_right" indicates which side we want to zero-fill from.
976static uint64_t ReadUnsignedLong(const byte* ptr, int zwidth, bool fill_on_right) {
977  uint64_t val = 0;
978  if (!fill_on_right) {
979    for (int i = zwidth; i >= 0; --i) {
980      val = (val >> 8) | (((uint64_t)*ptr++) << 56);
981    }
982    val >>= (7 - zwidth) * 8;
983  } else {
984    for (int i = zwidth; i >= 0; --i) {
985      val = (val >> 8) | (((uint64_t)*ptr++) << 56);
986    }
987  }
988  return val;
989}
990
991EncodedStaticFieldValueIterator::EncodedStaticFieldValueIterator(const DexFile& dex_file,
992                                                                 SirtRef<mirror::DexCache>* dex_cache,
993                                                                 SirtRef<mirror::ClassLoader>* class_loader,
994                                                                 ClassLinker* linker,
995                                                                 const DexFile::ClassDef& class_def)
996    : dex_file_(dex_file), dex_cache_(dex_cache), class_loader_(class_loader), linker_(linker),
997      array_size_(), pos_(-1), type_(kByte) {
998  DCHECK(dex_cache != nullptr);
999  DCHECK(class_loader != nullptr);
1000  ptr_ = dex_file.GetEncodedStaticFieldValuesArray(class_def);
1001  if (ptr_ == NULL) {
1002    array_size_ = 0;
1003  } else {
1004    array_size_ = DecodeUnsignedLeb128(&ptr_);
1005  }
1006  if (array_size_ > 0) {
1007    Next();
1008  }
1009}
1010
1011void EncodedStaticFieldValueIterator::Next() {
1012  pos_++;
1013  if (pos_ >= array_size_) {
1014    return;
1015  }
1016  byte value_type = *ptr_++;
1017  byte value_arg = value_type >> kEncodedValueArgShift;
1018  size_t width = value_arg + 1;  // assume and correct later
1019  type_ = static_cast<ValueType>(value_type & kEncodedValueTypeMask);
1020  switch (type_) {
1021  case kBoolean:
1022    jval_.i = (value_arg != 0) ? 1 : 0;
1023    width = 0;
1024    break;
1025  case kByte:
1026    jval_.i = ReadSignedInt(ptr_, value_arg);
1027    CHECK(IsInt(8, jval_.i));
1028    break;
1029  case kShort:
1030    jval_.i = ReadSignedInt(ptr_, value_arg);
1031    CHECK(IsInt(16, jval_.i));
1032    break;
1033  case kChar:
1034    jval_.i = ReadUnsignedInt(ptr_, value_arg, false);
1035    CHECK(IsUint(16, jval_.i));
1036    break;
1037  case kInt:
1038    jval_.i = ReadSignedInt(ptr_, value_arg);
1039    break;
1040  case kLong:
1041    jval_.j = ReadSignedLong(ptr_, value_arg);
1042    break;
1043  case kFloat:
1044    jval_.i = ReadUnsignedInt(ptr_, value_arg, true);
1045    break;
1046  case kDouble:
1047    jval_.j = ReadUnsignedLong(ptr_, value_arg, true);
1048    break;
1049  case kString:
1050  case kType:
1051    jval_.i = ReadUnsignedInt(ptr_, value_arg, false);
1052    break;
1053  case kField:
1054  case kMethod:
1055  case kEnum:
1056  case kArray:
1057  case kAnnotation:
1058    UNIMPLEMENTED(FATAL) << ": type " << type_;
1059    break;
1060  case kNull:
1061    jval_.l = NULL;
1062    width = 0;
1063    break;
1064  default:
1065    LOG(FATAL) << "Unreached";
1066  }
1067  ptr_ += width;
1068}
1069
1070void EncodedStaticFieldValueIterator::ReadValueToField(mirror::ArtField* field) const {
1071  switch (type_) {
1072    case kBoolean: field->SetBoolean(field->GetDeclaringClass(), jval_.z); break;
1073    case kByte:    field->SetByte(field->GetDeclaringClass(), jval_.b); break;
1074    case kShort:   field->SetShort(field->GetDeclaringClass(), jval_.s); break;
1075    case kChar:    field->SetChar(field->GetDeclaringClass(), jval_.c); break;
1076    case kInt:     field->SetInt(field->GetDeclaringClass(), jval_.i); break;
1077    case kLong:    field->SetLong(field->GetDeclaringClass(), jval_.j); break;
1078    case kFloat:   field->SetFloat(field->GetDeclaringClass(), jval_.f); break;
1079    case kDouble:  field->SetDouble(field->GetDeclaringClass(), jval_.d); break;
1080    case kNull:    field->SetObject(field->GetDeclaringClass(), NULL); break;
1081    case kString: {
1082      CHECK(!kMovingFields);
1083      mirror::String* resolved = linker_->ResolveString(dex_file_, jval_.i, *dex_cache_);
1084      field->SetObject(field->GetDeclaringClass(), resolved);
1085      break;
1086    }
1087    case kType: {
1088      CHECK(!kMovingFields);
1089      mirror::Class* resolved = linker_->ResolveType(dex_file_, jval_.i, *dex_cache_,
1090                                                     *class_loader_);
1091      field->SetObject(field->GetDeclaringClass(), resolved);
1092      break;
1093    }
1094    default: UNIMPLEMENTED(FATAL) << ": type " << type_;
1095  }
1096}
1097
1098CatchHandlerIterator::CatchHandlerIterator(const DexFile::CodeItem& code_item, uint32_t address) {
1099  handler_.address_ = -1;
1100  int32_t offset = -1;
1101
1102  // Short-circuit the overwhelmingly common cases.
1103  switch (code_item.tries_size_) {
1104    case 0:
1105      break;
1106    case 1: {
1107      const DexFile::TryItem* tries = DexFile::GetTryItems(code_item, 0);
1108      uint32_t start = tries->start_addr_;
1109      if (address >= start) {
1110        uint32_t end = start + tries->insn_count_;
1111        if (address < end) {
1112          offset = tries->handler_off_;
1113        }
1114      }
1115      break;
1116    }
1117    default:
1118      offset = DexFile::FindCatchHandlerOffset(code_item, address);
1119  }
1120  Init(code_item, offset);
1121}
1122
1123CatchHandlerIterator::CatchHandlerIterator(const DexFile::CodeItem& code_item,
1124                                           const DexFile::TryItem& try_item) {
1125  handler_.address_ = -1;
1126  Init(code_item, try_item.handler_off_);
1127}
1128
1129void CatchHandlerIterator::Init(const DexFile::CodeItem& code_item,
1130                                int32_t offset) {
1131  if (offset >= 0) {
1132    Init(DexFile::GetCatchHandlerData(code_item, offset));
1133  } else {
1134    // Not found, initialize as empty
1135    current_data_ = NULL;
1136    remaining_count_ = -1;
1137    catch_all_ = false;
1138    DCHECK(!HasNext());
1139  }
1140}
1141
1142void CatchHandlerIterator::Init(const byte* handler_data) {
1143  current_data_ = handler_data;
1144  remaining_count_ = DecodeSignedLeb128(&current_data_);
1145
1146  // If remaining_count_ is non-positive, then it is the negative of
1147  // the number of catch types, and the catches are followed by a
1148  // catch-all handler.
1149  if (remaining_count_ <= 0) {
1150    catch_all_ = true;
1151    remaining_count_ = -remaining_count_;
1152  } else {
1153    catch_all_ = false;
1154  }
1155  Next();
1156}
1157
1158void CatchHandlerIterator::Next() {
1159  if (remaining_count_ > 0) {
1160    handler_.type_idx_ = DecodeUnsignedLeb128(&current_data_);
1161    handler_.address_  = DecodeUnsignedLeb128(&current_data_);
1162    remaining_count_--;
1163    return;
1164  }
1165
1166  if (catch_all_) {
1167    handler_.type_idx_ = DexFile::kDexNoIndex16;
1168    handler_.address_  = DecodeUnsignedLeb128(&current_data_);
1169    catch_all_ = false;
1170    return;
1171  }
1172
1173  // no more handler
1174  remaining_count_ = -1;
1175}
1176
1177}  // namespace art
1178