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      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 #ifndef ART_LIBDEXFILE_DEX_DEX_FILE_H_
     18 #define ART_LIBDEXFILE_DEX_DEX_FILE_H_
     19 
     20 #include <memory>
     21 #include <string>
     22 #include <string_view>
     23 #include <vector>
     24 
     25 #include <android-base/logging.h>
     26 
     27 #include "base/globals.h"
     28 #include "base/hiddenapi_domain.h"
     29 #include "base/macros.h"
     30 #include "base/value_object.h"
     31 #include "class_iterator.h"
     32 #include "dex_file_structs.h"
     33 #include "dex_file_types.h"
     34 #include "jni.h"
     35 #include "modifiers.h"
     36 #include "signature.h"
     37 
     38 namespace art {
     39 
     40 class ClassDataItemIterator;
     41 class CompactDexFile;
     42 class DexInstructionIterator;
     43 enum InvokeType : uint32_t;
     44 template <typename Iter> class IterationRange;
     45 class MemMap;
     46 class OatDexFile;
     47 class StandardDexFile;
     48 class ZipArchive;
     49 
     50 // Some instances of DexFile own the storage referred to by DexFile.  Clients who create
     51 // such management do so by subclassing Container.
     52 class DexFileContainer {
     53  public:
     54   DexFileContainer() { }
     55   virtual ~DexFileContainer() { }
     56   virtual int GetPermissions() = 0;
     57   virtual bool IsReadOnly() = 0;
     58   virtual bool EnableWrite() = 0;
     59   virtual bool DisableWrite() = 0;
     60 
     61  private:
     62   DISALLOW_COPY_AND_ASSIGN(DexFileContainer);
     63 };
     64 
     65 // Dex file is the API that exposes native dex files (ordinary dex files) and CompactDex.
     66 // Originally, the dex file format used by ART was mostly the same as APKs. The only change was
     67 // quickened opcodes and layout optimizations.
     68 // Since ART needs to support both native dex files and CompactDex files, the DexFile interface
     69 // provides an abstraction to facilitate this.
     70 class DexFile {
     71  public:
     72   // Number of bytes in the dex file magic.
     73   static constexpr size_t kDexMagicSize = 4;
     74   static constexpr size_t kDexVersionLen = 4;
     75 
     76   // First Dex format version enforcing class definition ordering rules.
     77   static const uint32_t kClassDefinitionOrderEnforcedVersion = 37;
     78 
     79   static constexpr size_t kSha1DigestSize = 20;
     80   static constexpr uint32_t kDexEndianConstant = 0x12345678;
     81 
     82   // The value of an invalid index.
     83   static const uint16_t kDexNoIndex16 = 0xFFFF;
     84   static const uint32_t kDexNoIndex32 = 0xFFFFFFFF;
     85 
     86   // Raw header_item.
     87   struct Header {
     88     uint8_t magic_[8] = {};
     89     uint32_t checksum_ = 0;  // See also location_checksum_
     90     uint8_t signature_[kSha1DigestSize] = {};
     91     uint32_t file_size_ = 0;  // size of entire file
     92     uint32_t header_size_ = 0;  // offset to start of next section
     93     uint32_t endian_tag_ = 0;
     94     uint32_t link_size_ = 0;  // unused
     95     uint32_t link_off_ = 0;  // unused
     96     uint32_t map_off_ = 0;  // map list offset from data_off_
     97     uint32_t string_ids_size_ = 0;  // number of StringIds
     98     uint32_t string_ids_off_ = 0;  // file offset of StringIds array
     99     uint32_t type_ids_size_ = 0;  // number of TypeIds, we don't support more than 65535
    100     uint32_t type_ids_off_ = 0;  // file offset of TypeIds array
    101     uint32_t proto_ids_size_ = 0;  // number of ProtoIds, we don't support more than 65535
    102     uint32_t proto_ids_off_ = 0;  // file offset of ProtoIds array
    103     uint32_t field_ids_size_ = 0;  // number of FieldIds
    104     uint32_t field_ids_off_ = 0;  // file offset of FieldIds array
    105     uint32_t method_ids_size_ = 0;  // number of MethodIds
    106     uint32_t method_ids_off_ = 0;  // file offset of MethodIds array
    107     uint32_t class_defs_size_ = 0;  // number of ClassDefs
    108     uint32_t class_defs_off_ = 0;  // file offset of ClassDef array
    109     uint32_t data_size_ = 0;  // size of data section
    110     uint32_t data_off_ = 0;  // file offset of data section
    111 
    112     // Decode the dex magic version
    113     uint32_t GetVersion() const;
    114   };
    115 
    116   // Map item type codes.
    117   enum MapItemType : uint16_t {  // private
    118     kDexTypeHeaderItem               = 0x0000,
    119     kDexTypeStringIdItem             = 0x0001,
    120     kDexTypeTypeIdItem               = 0x0002,
    121     kDexTypeProtoIdItem              = 0x0003,
    122     kDexTypeFieldIdItem              = 0x0004,
    123     kDexTypeMethodIdItem             = 0x0005,
    124     kDexTypeClassDefItem             = 0x0006,
    125     kDexTypeCallSiteIdItem           = 0x0007,
    126     kDexTypeMethodHandleItem         = 0x0008,
    127     kDexTypeMapList                  = 0x1000,
    128     kDexTypeTypeList                 = 0x1001,
    129     kDexTypeAnnotationSetRefList     = 0x1002,
    130     kDexTypeAnnotationSetItem        = 0x1003,
    131     kDexTypeClassDataItem            = 0x2000,
    132     kDexTypeCodeItem                 = 0x2001,
    133     kDexTypeStringDataItem           = 0x2002,
    134     kDexTypeDebugInfoItem            = 0x2003,
    135     kDexTypeAnnotationItem           = 0x2004,
    136     kDexTypeEncodedArrayItem         = 0x2005,
    137     kDexTypeAnnotationsDirectoryItem = 0x2006,
    138     kDexTypeHiddenapiClassData       = 0xF000,
    139   };
    140 
    141   // MethodHandle Types
    142   enum class MethodHandleType : uint16_t {  // private
    143     kStaticPut         = 0x0000,  // a setter for a given static field.
    144     kStaticGet         = 0x0001,  // a getter for a given static field.
    145     kInstancePut       = 0x0002,  // a setter for a given instance field.
    146     kInstanceGet       = 0x0003,  // a getter for a given instance field.
    147     kInvokeStatic      = 0x0004,  // an invoker for a given static method.
    148     kInvokeInstance    = 0x0005,  // invoke_instance : an invoker for a given instance method. This
    149                                   // can be any non-static method on any class (or interface) except
    150                                   // for <init>.
    151     kInvokeConstructor = 0x0006,  // an invoker for a given constructor.
    152     kInvokeDirect      = 0x0007,  // an invoker for a direct (special) method.
    153     kInvokeInterface   = 0x0008,  // an invoker for an interface method.
    154     kLast = kInvokeInterface
    155   };
    156 
    157   // Annotation constants.
    158   enum {
    159     kDexVisibilityBuild         = 0x00,     /* annotation visibility */
    160     kDexVisibilityRuntime       = 0x01,
    161     kDexVisibilitySystem        = 0x02,
    162 
    163     kDexAnnotationByte          = 0x00,
    164     kDexAnnotationShort         = 0x02,
    165     kDexAnnotationChar          = 0x03,
    166     kDexAnnotationInt           = 0x04,
    167     kDexAnnotationLong          = 0x06,
    168     kDexAnnotationFloat         = 0x10,
    169     kDexAnnotationDouble        = 0x11,
    170     kDexAnnotationMethodType    = 0x15,
    171     kDexAnnotationMethodHandle  = 0x16,
    172     kDexAnnotationString        = 0x17,
    173     kDexAnnotationType          = 0x18,
    174     kDexAnnotationField         = 0x19,
    175     kDexAnnotationMethod        = 0x1a,
    176     kDexAnnotationEnum          = 0x1b,
    177     kDexAnnotationArray         = 0x1c,
    178     kDexAnnotationAnnotation    = 0x1d,
    179     kDexAnnotationNull          = 0x1e,
    180     kDexAnnotationBoolean       = 0x1f,
    181 
    182     kDexAnnotationValueTypeMask = 0x1f,     /* low 5 bits */
    183     kDexAnnotationValueArgShift = 5,
    184   };
    185 
    186   enum AnnotationResultStyle {  // private
    187     kAllObjects,
    188     kPrimitivesOrObjects,
    189     kAllRaw
    190   };
    191 
    192   struct AnnotationValue;
    193 
    194   // Closes a .dex file.
    195   virtual ~DexFile();
    196 
    197   const std::string& GetLocation() const {
    198     return location_;
    199   }
    200 
    201   // For DexFiles directly from .dex files, this is the checksum from the DexFile::Header.
    202   // For DexFiles opened from a zip files, this will be the ZipEntry CRC32 of classes.dex.
    203   uint32_t GetLocationChecksum() const {
    204     return location_checksum_;
    205   }
    206 
    207   const Header& GetHeader() const {
    208     DCHECK(header_ != nullptr) << GetLocation();
    209     return *header_;
    210   }
    211 
    212   // Decode the dex magic version
    213   uint32_t GetDexVersion() const {
    214     return GetHeader().GetVersion();
    215   }
    216 
    217   // Returns true if the byte string points to the magic value.
    218   virtual bool IsMagicValid() const = 0;
    219 
    220   // Returns true if the byte string after the magic is the correct value.
    221   virtual bool IsVersionValid() const = 0;
    222 
    223   // Returns true if the dex file supports default methods.
    224   virtual bool SupportsDefaultMethods() const = 0;
    225 
    226   // Returns the maximum size in bytes needed to store an equivalent dex file strictly conforming to
    227   // the dex file specification. That is the size if we wanted to get rid of all the
    228   // quickening/compact-dexing/etc.
    229   //
    230   // TODO This should really be an exact size! b/72402467
    231   virtual size_t GetDequickenedSize() const = 0;
    232 
    233   // Returns the number of string identifiers in the .dex file.
    234   size_t NumStringIds() const {
    235     DCHECK(header_ != nullptr) << GetLocation();
    236     return header_->string_ids_size_;
    237   }
    238 
    239   // Returns the StringId at the specified index.
    240   const dex::StringId& GetStringId(dex::StringIndex idx) const {
    241     DCHECK_LT(idx.index_, NumStringIds()) << GetLocation();
    242     return string_ids_[idx.index_];
    243   }
    244 
    245   dex::StringIndex GetIndexForStringId(const dex::StringId& string_id) const {
    246     CHECK_GE(&string_id, string_ids_) << GetLocation();
    247     CHECK_LT(&string_id, string_ids_ + header_->string_ids_size_) << GetLocation();
    248     return dex::StringIndex(&string_id - string_ids_);
    249   }
    250 
    251   int32_t GetStringLength(const dex::StringId& string_id) const;
    252 
    253   // Returns a pointer to the UTF-8 string data referred to by the given string_id as well as the
    254   // length of the string when decoded as a UTF-16 string. Note the UTF-16 length is not the same
    255   // as the string length of the string data.
    256   const char* GetStringDataAndUtf16Length(const dex::StringId& string_id,
    257                                           uint32_t* utf16_length) const;
    258 
    259   const char* GetStringData(const dex::StringId& string_id) const;
    260 
    261   // Index version of GetStringDataAndUtf16Length.
    262   const char* StringDataAndUtf16LengthByIdx(dex::StringIndex idx, uint32_t* utf16_length) const;
    263 
    264   const char* StringDataByIdx(dex::StringIndex idx) const;
    265   std::string_view StringViewByIdx(dex::StringIndex idx) const;
    266 
    267   // Looks up a string id for a given modified utf8 string.
    268   const dex::StringId* FindStringId(const char* string) const;
    269 
    270   const dex::TypeId* FindTypeId(const char* string) const;
    271 
    272   // Returns the number of type identifiers in the .dex file.
    273   uint32_t NumTypeIds() const {
    274     DCHECK(header_ != nullptr) << GetLocation();
    275     return header_->type_ids_size_;
    276   }
    277 
    278   bool IsTypeIndexValid(dex::TypeIndex idx) const {
    279     return idx.IsValid() && idx.index_ < NumTypeIds();
    280   }
    281 
    282   // Returns the TypeId at the specified index.
    283   const dex::TypeId& GetTypeId(dex::TypeIndex idx) const {
    284     DCHECK_LT(idx.index_, NumTypeIds()) << GetLocation();
    285     return type_ids_[idx.index_];
    286   }
    287 
    288   dex::TypeIndex GetIndexForTypeId(const dex::TypeId& type_id) const {
    289     CHECK_GE(&type_id, type_ids_) << GetLocation();
    290     CHECK_LT(&type_id, type_ids_ + header_->type_ids_size_) << GetLocation();
    291     size_t result = &type_id - type_ids_;
    292     DCHECK_LT(result, 65536U) << GetLocation();
    293     return dex::TypeIndex(static_cast<uint16_t>(result));
    294   }
    295 
    296   // Get the descriptor string associated with a given type index.
    297   const char* StringByTypeIdx(dex::TypeIndex idx, uint32_t* unicode_length) const;
    298 
    299   const char* StringByTypeIdx(dex::TypeIndex idx) const;
    300 
    301   // Returns the type descriptor string of a type id.
    302   const char* GetTypeDescriptor(const dex::TypeId& type_id) const;
    303 
    304   // Looks up a type for the given string index
    305   const dex::TypeId* FindTypeId(dex::StringIndex string_idx) const;
    306 
    307   // Returns the number of field identifiers in the .dex file.
    308   size_t NumFieldIds() const {
    309     DCHECK(header_ != nullptr) << GetLocation();
    310     return header_->field_ids_size_;
    311   }
    312 
    313   // Returns the FieldId at the specified index.
    314   const dex::FieldId& GetFieldId(uint32_t idx) const {
    315     DCHECK_LT(idx, NumFieldIds()) << GetLocation();
    316     return field_ids_[idx];
    317   }
    318 
    319   uint32_t GetIndexForFieldId(const dex::FieldId& field_id) const {
    320     CHECK_GE(&field_id, field_ids_) << GetLocation();
    321     CHECK_LT(&field_id, field_ids_ + header_->field_ids_size_) << GetLocation();
    322     return &field_id - field_ids_;
    323   }
    324 
    325   // Looks up a field by its declaring class, name and type
    326   const dex::FieldId* FindFieldId(const dex::TypeId& declaring_klass,
    327                                   const dex::StringId& name,
    328                                   const dex::TypeId& type) const;
    329 
    330   uint32_t FindCodeItemOffset(const dex::ClassDef& class_def,
    331                               uint32_t dex_method_idx) const;
    332 
    333   virtual uint32_t GetCodeItemSize(const dex::CodeItem& disk_code_item) const = 0;
    334 
    335   // Returns the declaring class descriptor string of a field id.
    336   const char* GetFieldDeclaringClassDescriptor(const dex::FieldId& field_id) const {
    337     const dex::TypeId& type_id = GetTypeId(field_id.class_idx_);
    338     return GetTypeDescriptor(type_id);
    339   }
    340 
    341   // Returns the class descriptor string of a field id.
    342   const char* GetFieldTypeDescriptor(const dex::FieldId& field_id) const;
    343 
    344   // Returns the name of a field id.
    345   const char* GetFieldName(const dex::FieldId& field_id) const;
    346 
    347   // Returns the number of method identifiers in the .dex file.
    348   size_t NumMethodIds() const {
    349     DCHECK(header_ != nullptr) << GetLocation();
    350     return header_->method_ids_size_;
    351   }
    352 
    353   // Returns the MethodId at the specified index.
    354   const dex::MethodId& GetMethodId(uint32_t idx) const {
    355     DCHECK_LT(idx, NumMethodIds()) << GetLocation();
    356     return method_ids_[idx];
    357   }
    358 
    359   uint32_t GetIndexForMethodId(const dex::MethodId& method_id) const {
    360     CHECK_GE(&method_id, method_ids_) << GetLocation();
    361     CHECK_LT(&method_id, method_ids_ + header_->method_ids_size_) << GetLocation();
    362     return &method_id - method_ids_;
    363   }
    364 
    365   // Looks up a method by its declaring class, name and proto_id
    366   const dex::MethodId* FindMethodId(const dex::TypeId& declaring_klass,
    367                                     const dex::StringId& name,
    368                                     const dex::ProtoId& signature) const;
    369 
    370   // Returns the declaring class descriptor string of a method id.
    371   const char* GetMethodDeclaringClassDescriptor(const dex::MethodId& method_id) const;
    372 
    373   // Returns the prototype of a method id.
    374   const dex::ProtoId& GetMethodPrototype(const dex::MethodId& method_id) const {
    375     return GetProtoId(method_id.proto_idx_);
    376   }
    377 
    378   // Returns a representation of the signature of a method id.
    379   const Signature GetMethodSignature(const dex::MethodId& method_id) const;
    380 
    381   // Returns a representation of the signature of a proto id.
    382   const Signature GetProtoSignature(const dex::ProtoId& proto_id) const;
    383 
    384   // Returns the name of a method id.
    385   const char* GetMethodName(const dex::MethodId& method_id) const;
    386   const char* GetMethodName(const dex::MethodId& method_id, uint32_t* utf_length) const;
    387   const char* GetMethodName(uint32_t idx, uint32_t* utf_length) const;
    388 
    389   // Returns the shorty of a method by its index.
    390   const char* GetMethodShorty(uint32_t idx) const;
    391 
    392   // Returns the shorty of a method id.
    393   const char* GetMethodShorty(const dex::MethodId& method_id) const;
    394   const char* GetMethodShorty(const dex::MethodId& method_id, uint32_t* length) const;
    395 
    396   // Returns the number of class definitions in the .dex file.
    397   uint32_t NumClassDefs() const {
    398     DCHECK(header_ != nullptr) << GetLocation();
    399     return header_->class_defs_size_;
    400   }
    401 
    402   // Returns the ClassDef at the specified index.
    403   const dex::ClassDef& GetClassDef(uint16_t idx) const {
    404     DCHECK_LT(idx, NumClassDefs()) << GetLocation();
    405     return class_defs_[idx];
    406   }
    407 
    408   uint16_t GetIndexForClassDef(const dex::ClassDef& class_def) const {
    409     CHECK_GE(&class_def, class_defs_) << GetLocation();
    410     CHECK_LT(&class_def, class_defs_ + header_->class_defs_size_) << GetLocation();
    411     return &class_def - class_defs_;
    412   }
    413 
    414   // Returns the class descriptor string of a class definition.
    415   const char* GetClassDescriptor(const dex::ClassDef& class_def) const;
    416 
    417   // Looks up a class definition by its type index.
    418   const dex::ClassDef* FindClassDef(dex::TypeIndex type_idx) const;
    419 
    420   const dex::TypeList* GetInterfacesList(const dex::ClassDef& class_def) const {
    421     return DataPointer<dex::TypeList>(class_def.interfaces_off_);
    422   }
    423 
    424   uint32_t NumMethodHandles() const {
    425     return num_method_handles_;
    426   }
    427 
    428   const dex::MethodHandleItem& GetMethodHandle(uint32_t idx) const {
    429     CHECK_LT(idx, NumMethodHandles());
    430     return method_handles_[idx];
    431   }
    432 
    433   uint32_t NumCallSiteIds() const {
    434     return num_call_site_ids_;
    435   }
    436 
    437   const dex::CallSiteIdItem& GetCallSiteId(uint32_t idx) const {
    438     CHECK_LT(idx, NumCallSiteIds());
    439     return call_site_ids_[idx];
    440   }
    441 
    442   // Returns a pointer to the raw memory mapped class_data_item
    443   const uint8_t* GetClassData(const dex::ClassDef& class_def) const {
    444     return DataPointer<uint8_t>(class_def.class_data_off_);
    445   }
    446 
    447   // Return the code item for a provided offset.
    448   const dex::CodeItem* GetCodeItem(const uint32_t code_off) const {
    449     // May be null for native or abstract methods.
    450     return DataPointer<dex::CodeItem>(code_off);
    451   }
    452 
    453   const char* GetReturnTypeDescriptor(const dex::ProtoId& proto_id) const;
    454 
    455   // Returns the number of prototype identifiers in the .dex file.
    456   size_t NumProtoIds() const {
    457     DCHECK(header_ != nullptr) << GetLocation();
    458     return header_->proto_ids_size_;
    459   }
    460 
    461   // Returns the ProtoId at the specified index.
    462   const dex::ProtoId& GetProtoId(dex::ProtoIndex idx) const {
    463     DCHECK_LT(idx.index_, NumProtoIds()) << GetLocation();
    464     return proto_ids_[idx.index_];
    465   }
    466 
    467   dex::ProtoIndex GetIndexForProtoId(const dex::ProtoId& proto_id) const {
    468     CHECK_GE(&proto_id, proto_ids_) << GetLocation();
    469     CHECK_LT(&proto_id, proto_ids_ + header_->proto_ids_size_) << GetLocation();
    470     return dex::ProtoIndex(&proto_id - proto_ids_);
    471   }
    472 
    473   // Looks up a proto id for a given return type and signature type list
    474   const dex::ProtoId* FindProtoId(dex::TypeIndex return_type_idx,
    475                                   const dex::TypeIndex* signature_type_idxs,
    476                              uint32_t signature_length) const;
    477   const dex::ProtoId* FindProtoId(dex::TypeIndex return_type_idx,
    478                                   const std::vector<dex::TypeIndex>& signature_type_idxs) const {
    479     return FindProtoId(return_type_idx, &signature_type_idxs[0], signature_type_idxs.size());
    480   }
    481 
    482   // Given a signature place the type ids into the given vector, returns true on success
    483   bool CreateTypeList(std::string_view signature,
    484                       dex::TypeIndex* return_type_idx,
    485                       std::vector<dex::TypeIndex>* param_type_idxs) const;
    486 
    487   // Returns the short form method descriptor for the given prototype.
    488   const char* GetShorty(dex::ProtoIndex proto_idx) const;
    489 
    490   const dex::TypeList* GetProtoParameters(const dex::ProtoId& proto_id) const {
    491     return DataPointer<dex::TypeList>(proto_id.parameters_off_);
    492   }
    493 
    494   const uint8_t* GetEncodedStaticFieldValuesArray(const dex::ClassDef& class_def) const {
    495     return DataPointer<uint8_t>(class_def.static_values_off_);
    496   }
    497 
    498   const uint8_t* GetCallSiteEncodedValuesArray(const dex::CallSiteIdItem& call_site_id) const {
    499     return DataBegin() + call_site_id.data_off_;
    500   }
    501 
    502   dex::ProtoIndex GetProtoIndexForCallSite(uint32_t call_site_idx) const;
    503 
    504   static const dex::TryItem* GetTryItems(const DexInstructionIterator& code_item_end,
    505                                          uint32_t offset);
    506 
    507   // Get the base of the encoded data for the given DexCode.
    508   static const uint8_t* GetCatchHandlerData(const DexInstructionIterator& code_item_end,
    509                                             uint32_t tries_size,
    510                                             uint32_t offset);
    511 
    512   // Find which try region is associated with the given address (ie dex pc). Returns -1 if none.
    513   static int32_t FindTryItem(const dex::TryItem* try_items, uint32_t tries_size, uint32_t address);
    514 
    515   // Get the pointer to the start of the debugging data
    516   const uint8_t* GetDebugInfoStream(uint32_t debug_info_off) const {
    517     // Check that the offset is in bounds.
    518     // Note that although the specification says that 0 should be used if there
    519     // is no debug information, some applications incorrectly use 0xFFFFFFFF.
    520     return (debug_info_off == 0 || debug_info_off >= data_size_)
    521         ? nullptr
    522         : DataBegin() + debug_info_off;
    523   }
    524 
    525   struct PositionInfo {
    526     PositionInfo() = default;
    527 
    528     uint32_t address_ = 0;  // In 16-bit code units.
    529     uint32_t line_ = 0;  // Source code line number starting at 1.
    530     const char* source_file_ = nullptr;  // nullptr if the file from ClassDef still applies.
    531     bool prologue_end_ = false;
    532     bool epilogue_begin_ = false;
    533   };
    534 
    535   struct LocalInfo {
    536     LocalInfo() = default;
    537 
    538     const char* name_ = nullptr;  // E.g., list.  It can be nullptr if unknown.
    539     const char* descriptor_ = nullptr;  // E.g., Ljava/util/LinkedList;
    540     const char* signature_ = nullptr;  // E.g., java.util.LinkedList<java.lang.Integer>
    541     uint32_t start_address_ = 0;  // PC location where the local is first defined.
    542     uint32_t end_address_ = 0;  // PC location where the local is no longer defined.
    543     uint16_t reg_ = 0;  // Dex register which stores the values.
    544     bool is_live_ = false;  // Is the local defined and live.
    545   };
    546 
    547   // Callback for "new locals table entry".
    548   typedef void (*DexDebugNewLocalCb)(void* context, const LocalInfo& entry);
    549 
    550   const dex::AnnotationsDirectoryItem* GetAnnotationsDirectory(const dex::ClassDef& class_def)
    551       const {
    552     return DataPointer<dex::AnnotationsDirectoryItem>(class_def.annotations_off_);
    553   }
    554 
    555   const dex::AnnotationSetItem* GetClassAnnotationSet(const dex::AnnotationsDirectoryItem* anno_dir)
    556       const {
    557     return DataPointer<dex::AnnotationSetItem>(anno_dir->class_annotations_off_);
    558   }
    559 
    560   const dex::FieldAnnotationsItem* GetFieldAnnotations(
    561       const dex::AnnotationsDirectoryItem* anno_dir) const {
    562     return (anno_dir->fields_size_ == 0)
    563          ? nullptr
    564          : reinterpret_cast<const dex::FieldAnnotationsItem*>(&anno_dir[1]);
    565   }
    566 
    567   const dex::MethodAnnotationsItem* GetMethodAnnotations(
    568       const dex::AnnotationsDirectoryItem* anno_dir) const {
    569     if (anno_dir->methods_size_ == 0) {
    570       return nullptr;
    571     }
    572     // Skip past the header and field annotations.
    573     const uint8_t* addr = reinterpret_cast<const uint8_t*>(&anno_dir[1]);
    574     addr += anno_dir->fields_size_ * sizeof(dex::FieldAnnotationsItem);
    575     return reinterpret_cast<const dex::MethodAnnotationsItem*>(addr);
    576   }
    577 
    578   const dex::ParameterAnnotationsItem* GetParameterAnnotations(
    579       const dex::AnnotationsDirectoryItem* anno_dir) const {
    580     if (anno_dir->parameters_size_ == 0) {
    581       return nullptr;
    582     }
    583     // Skip past the header, field annotations, and method annotations.
    584     const uint8_t* addr = reinterpret_cast<const uint8_t*>(&anno_dir[1]);
    585     addr += anno_dir->fields_size_ * sizeof(dex::FieldAnnotationsItem);
    586     addr += anno_dir->methods_size_ * sizeof(dex::MethodAnnotationsItem);
    587     return reinterpret_cast<const dex::ParameterAnnotationsItem*>(addr);
    588   }
    589 
    590   const dex::AnnotationSetItem* GetFieldAnnotationSetItem(
    591       const dex::FieldAnnotationsItem& anno_item) const {
    592     return DataPointer<dex::AnnotationSetItem>(anno_item.annotations_off_);
    593   }
    594 
    595   const dex::AnnotationSetItem* GetMethodAnnotationSetItem(
    596       const dex::MethodAnnotationsItem& anno_item) const {
    597     return DataPointer<dex::AnnotationSetItem>(anno_item.annotations_off_);
    598   }
    599 
    600   const dex::AnnotationSetRefList* GetParameterAnnotationSetRefList(
    601       const dex::ParameterAnnotationsItem* anno_item) const {
    602     return DataPointer<dex::AnnotationSetRefList>(anno_item->annotations_off_);
    603   }
    604 
    605   ALWAYS_INLINE const dex::AnnotationItem* GetAnnotationItemAtOffset(uint32_t offset) const {
    606     return DataPointer<dex::AnnotationItem>(offset);
    607   }
    608 
    609   ALWAYS_INLINE const dex::HiddenapiClassData* GetHiddenapiClassDataAtOffset(uint32_t offset)
    610       const {
    611     return DataPointer<dex::HiddenapiClassData>(offset);
    612   }
    613 
    614   ALWAYS_INLINE const dex::HiddenapiClassData* GetHiddenapiClassData() const {
    615     return hiddenapi_class_data_;
    616   }
    617 
    618   ALWAYS_INLINE bool HasHiddenapiClassData() const {
    619     return hiddenapi_class_data_ != nullptr;
    620   }
    621 
    622   const dex::AnnotationItem* GetAnnotationItem(const dex::AnnotationSetItem* set_item,
    623                                                uint32_t index) const {
    624     DCHECK_LE(index, set_item->size_);
    625     return GetAnnotationItemAtOffset(set_item->entries_[index]);
    626   }
    627 
    628   const dex::AnnotationSetItem* GetSetRefItemItem(const dex::AnnotationSetRefItem* anno_item)
    629       const {
    630     return DataPointer<dex::AnnotationSetItem>(anno_item->annotations_off_);
    631   }
    632 
    633   // Debug info opcodes and constants
    634   enum {
    635     DBG_END_SEQUENCE         = 0x00,
    636     DBG_ADVANCE_PC           = 0x01,
    637     DBG_ADVANCE_LINE         = 0x02,
    638     DBG_START_LOCAL          = 0x03,
    639     DBG_START_LOCAL_EXTENDED = 0x04,
    640     DBG_END_LOCAL            = 0x05,
    641     DBG_RESTART_LOCAL        = 0x06,
    642     DBG_SET_PROLOGUE_END     = 0x07,
    643     DBG_SET_EPILOGUE_BEGIN   = 0x08,
    644     DBG_SET_FILE             = 0x09,
    645     DBG_FIRST_SPECIAL        = 0x0a,
    646     DBG_LINE_BASE            = -4,
    647     DBG_LINE_RANGE           = 15,
    648   };
    649 
    650   // Returns false if there is no debugging information or if it cannot be decoded.
    651   template<typename NewLocalCallback, typename IndexToStringData, typename TypeIndexToStringData>
    652   static bool DecodeDebugLocalInfo(const uint8_t* stream,
    653                                    const std::string& location,
    654                                    const char* declaring_class_descriptor,
    655                                    const std::vector<const char*>& arg_descriptors,
    656                                    const std::string& method_name,
    657                                    bool is_static,
    658                                    uint16_t registers_size,
    659                                    uint16_t ins_size,
    660                                    uint16_t insns_size_in_code_units,
    661                                    const IndexToStringData& index_to_string_data,
    662                                    const TypeIndexToStringData& type_index_to_string_data,
    663                                    const NewLocalCallback& new_local) NO_THREAD_SAFETY_ANALYSIS;
    664   template<typename NewLocalCallback>
    665   bool DecodeDebugLocalInfo(uint32_t registers_size,
    666                             uint32_t ins_size,
    667                             uint32_t insns_size_in_code_units,
    668                             uint32_t debug_info_offset,
    669                             bool is_static,
    670                             uint32_t method_idx,
    671                             const NewLocalCallback& new_local) const;
    672 
    673   // Returns false if there is no debugging information or if it cannot be decoded.
    674   template<typename DexDebugNewPosition, typename IndexToStringData>
    675   static bool DecodeDebugPositionInfo(const uint8_t* stream,
    676                                       const IndexToStringData& index_to_string_data,
    677                                       const DexDebugNewPosition& position_functor);
    678 
    679   const char* GetSourceFile(const dex::ClassDef& class_def) const {
    680     if (!class_def.source_file_idx_.IsValid()) {
    681       return nullptr;
    682     } else {
    683       return StringDataByIdx(class_def.source_file_idx_);
    684     }
    685   }
    686 
    687   int GetPermissions() const;
    688 
    689   bool IsReadOnly() const;
    690 
    691   bool EnableWrite() const;
    692 
    693   bool DisableWrite() const;
    694 
    695   const uint8_t* Begin() const {
    696     return begin_;
    697   }
    698 
    699   size_t Size() const {
    700     return size_;
    701   }
    702 
    703   const uint8_t* DataBegin() const {
    704     return data_begin_;
    705   }
    706 
    707   size_t DataSize() const {
    708     return data_size_;
    709   }
    710 
    711   template <typename T>
    712   const T* DataPointer(size_t offset) const {
    713     DCHECK_LT(offset, DataSize()) << "Offset past end of data section";
    714     return (offset != 0u) ? reinterpret_cast<const T*>(DataBegin() + offset) : nullptr;
    715   }
    716 
    717   const OatDexFile* GetOatDexFile() const {
    718     return oat_dex_file_;
    719   }
    720 
    721   // Used by oat writer.
    722   void SetOatDexFile(OatDexFile* oat_dex_file) const {
    723     oat_dex_file_ = oat_dex_file;
    724   }
    725 
    726   // Read MapItems and validate/set remaining offsets.
    727   const dex::MapList* GetMapList() const {
    728     return reinterpret_cast<const dex::MapList*>(DataBegin() + header_->map_off_);
    729   }
    730 
    731   // Utility methods for reading integral values from a buffer.
    732   static int32_t ReadSignedInt(const uint8_t* ptr, int zwidth);
    733   static uint32_t ReadUnsignedInt(const uint8_t* ptr, int zwidth, bool fill_on_right);
    734   static int64_t ReadSignedLong(const uint8_t* ptr, int zwidth);
    735   static uint64_t ReadUnsignedLong(const uint8_t* ptr, int zwidth, bool fill_on_right);
    736 
    737   // Recalculates the checksum of the dex file. Does not use the current value in the header.
    738   virtual uint32_t CalculateChecksum() const;
    739   static uint32_t CalculateChecksum(const uint8_t* begin, size_t size);
    740   static uint32_t ChecksumMemoryRange(const uint8_t* begin, size_t size);
    741 
    742   // Number of bytes at the beginning of the dex file header which are skipped
    743   // when computing the adler32 checksum of the entire file.
    744   static constexpr uint32_t kNumNonChecksumBytes = OFFSETOF_MEMBER(DexFile::Header, signature_);
    745 
    746   // Returns a human-readable form of the method at an index.
    747   std::string PrettyMethod(uint32_t method_idx, bool with_signature = true) const;
    748   // Returns a human-readable form of the field at an index.
    749   std::string PrettyField(uint32_t field_idx, bool with_type = true) const;
    750   // Returns a human-readable form of the type at an index.
    751   std::string PrettyType(dex::TypeIndex type_idx) const;
    752 
    753   // Not virtual for performance reasons.
    754   ALWAYS_INLINE bool IsCompactDexFile() const {
    755     return is_compact_dex_;
    756   }
    757   ALWAYS_INLINE bool IsStandardDexFile() const {
    758     return !is_compact_dex_;
    759   }
    760   ALWAYS_INLINE const StandardDexFile* AsStandardDexFile() const;
    761   ALWAYS_INLINE const CompactDexFile* AsCompactDexFile() const;
    762 
    763   hiddenapi::Domain GetHiddenapiDomain() const { return hiddenapi_domain_; }
    764   void SetHiddenapiDomain(hiddenapi::Domain value) const { hiddenapi_domain_ = value; }
    765 
    766   bool IsInMainSection(const void* addr) const {
    767     return Begin() <= addr && addr < Begin() + Size();
    768   }
    769 
    770   bool IsInDataSection(const void* addr) const {
    771     return DataBegin() <= addr && addr < DataBegin() + DataSize();
    772   }
    773 
    774   DexFileContainer* GetContainer() const {
    775     return container_.get();
    776   }
    777 
    778   IterationRange<ClassIterator> GetClasses() const;
    779 
    780   template <typename Visitor>
    781   static uint32_t DecodeDebugInfoParameterNames(const uint8_t** debug_info,
    782                                                 const Visitor& visitor);
    783 
    784   static inline bool StringEquals(const DexFile* df1, dex::StringIndex sidx1,
    785                                   const DexFile* df2, dex::StringIndex sidx2);
    786 
    787  protected:
    788   // First Dex format version supporting default methods.
    789   static const uint32_t kDefaultMethodsVersion = 37;
    790 
    791   DexFile(const uint8_t* base,
    792           size_t size,
    793           const uint8_t* data_begin,
    794           size_t data_size,
    795           const std::string& location,
    796           uint32_t location_checksum,
    797           const OatDexFile* oat_dex_file,
    798           std::unique_ptr<DexFileContainer> container,
    799           bool is_compact_dex);
    800 
    801   // Top-level initializer that calls other Init methods.
    802   bool Init(std::string* error_msg);
    803 
    804   // Returns true if the header magic and version numbers are of the expected values.
    805   bool CheckMagicAndVersion(std::string* error_msg) const;
    806 
    807   // Initialize section info for sections only found in map. Returns true on success.
    808   void InitializeSectionsFromMapList();
    809 
    810   // The base address of the memory mapping.
    811   const uint8_t* const begin_;
    812 
    813   // The size of the underlying memory allocation in bytes.
    814   const size_t size_;
    815 
    816   // The base address of the data section (same as Begin() for standard dex).
    817   const uint8_t* const data_begin_;
    818 
    819   // The size of the data section.
    820   const size_t data_size_;
    821 
    822   // Typically the dex file name when available, alternatively some identifying string.
    823   //
    824   // The ClassLinker will use this to match DexFiles the boot class
    825   // path to DexCache::GetLocation when loading from an image.
    826   const std::string location_;
    827 
    828   const uint32_t location_checksum_;
    829 
    830   // Points to the header section.
    831   const Header* const header_;
    832 
    833   // Points to the base of the string identifier list.
    834   const dex::StringId* const string_ids_;
    835 
    836   // Points to the base of the type identifier list.
    837   const dex::TypeId* const type_ids_;
    838 
    839   // Points to the base of the field identifier list.
    840   const dex::FieldId* const field_ids_;
    841 
    842   // Points to the base of the method identifier list.
    843   const dex::MethodId* const method_ids_;
    844 
    845   // Points to the base of the prototype identifier list.
    846   const dex::ProtoId* const proto_ids_;
    847 
    848   // Points to the base of the class definition list.
    849   const dex::ClassDef* const class_defs_;
    850 
    851   // Points to the base of the method handles list.
    852   const dex::MethodHandleItem* method_handles_;
    853 
    854   // Number of elements in the method handles list.
    855   size_t num_method_handles_;
    856 
    857   // Points to the base of the call sites id list.
    858   const dex::CallSiteIdItem* call_site_ids_;
    859 
    860   // Number of elements in the call sites list.
    861   size_t num_call_site_ids_;
    862 
    863   // Points to the base of the hiddenapi class data item_, or nullptr if the dex
    864   // file does not have one.
    865   const dex::HiddenapiClassData* hiddenapi_class_data_;
    866 
    867   // If this dex file was loaded from an oat file, oat_dex_file_ contains a
    868   // pointer to the OatDexFile it was loaded from. Otherwise oat_dex_file_ is
    869   // null.
    870   mutable const OatDexFile* oat_dex_file_;
    871 
    872   // Manages the underlying memory allocation.
    873   std::unique_ptr<DexFileContainer> container_;
    874 
    875   // If the dex file is a compact dex file. If false then the dex file is a standard dex file.
    876   const bool is_compact_dex_;
    877 
    878   // The domain this dex file belongs to for hidden API access checks.
    879   // It is decleared `mutable` because the domain is assigned after the DexFile
    880   // has been created and can be changed later by the runtime.
    881   mutable hiddenapi::Domain hiddenapi_domain_;
    882 
    883   friend class DexFileLoader;
    884   friend class DexFileVerifierTest;
    885   friend class OatWriter;
    886 };
    887 
    888 std::ostream& operator<<(std::ostream& os, const DexFile& dex_file);
    889 
    890 // Iterate over a dex file's ProtoId's paramters
    891 class DexFileParameterIterator {
    892  public:
    893   DexFileParameterIterator(const DexFile& dex_file, const dex::ProtoId& proto_id)
    894       : dex_file_(dex_file) {
    895     type_list_ = dex_file_.GetProtoParameters(proto_id);
    896     if (type_list_ != nullptr) {
    897       size_ = type_list_->Size();
    898     }
    899   }
    900   bool HasNext() const { return pos_ < size_; }
    901   size_t Size() const { return size_; }
    902   void Next() { ++pos_; }
    903   dex::TypeIndex GetTypeIdx() {
    904     return type_list_->GetTypeItem(pos_).type_idx_;
    905   }
    906   const char* GetDescriptor() {
    907     return dex_file_.StringByTypeIdx(dex::TypeIndex(GetTypeIdx()));
    908   }
    909  private:
    910   const DexFile& dex_file_;
    911   const dex::TypeList* type_list_ = nullptr;
    912   uint32_t size_ = 0;
    913   uint32_t pos_ = 0;
    914   DISALLOW_IMPLICIT_CONSTRUCTORS(DexFileParameterIterator);
    915 };
    916 
    917 class EncodedArrayValueIterator {
    918  public:
    919   EncodedArrayValueIterator(const DexFile& dex_file, const uint8_t* array_data);
    920 
    921   bool HasNext() const { return pos_ < array_size_; }
    922 
    923   void Next();
    924 
    925   enum ValueType {
    926     kByte         = 0x00,
    927     kShort        = 0x02,
    928     kChar         = 0x03,
    929     kInt          = 0x04,
    930     kLong         = 0x06,
    931     kFloat        = 0x10,
    932     kDouble       = 0x11,
    933     kMethodType   = 0x15,
    934     kMethodHandle = 0x16,
    935     kString       = 0x17,
    936     kType         = 0x18,
    937     kField        = 0x19,
    938     kMethod       = 0x1a,
    939     kEnum         = 0x1b,
    940     kArray        = 0x1c,
    941     kAnnotation   = 0x1d,
    942     kNull         = 0x1e,
    943     kBoolean      = 0x1f,
    944   };
    945 
    946   ValueType GetValueType() const { return type_; }
    947   const jvalue& GetJavaValue() const { return jval_; }
    948 
    949  protected:
    950   static constexpr uint8_t kEncodedValueTypeMask = 0x1f;  // 0b11111
    951   static constexpr uint8_t kEncodedValueArgShift = 5;
    952 
    953   const DexFile& dex_file_;
    954   size_t array_size_;  // Size of array.
    955   size_t pos_;  // Current position.
    956   const uint8_t* ptr_;  // Pointer into encoded data array.
    957   ValueType type_;  // Type of current encoded value.
    958   jvalue jval_;  // Value of current encoded value.
    959 
    960  private:
    961   DISALLOW_IMPLICIT_CONSTRUCTORS(EncodedArrayValueIterator);
    962 };
    963 std::ostream& operator<<(std::ostream& os, const EncodedArrayValueIterator::ValueType& code);
    964 
    965 class EncodedStaticFieldValueIterator : public EncodedArrayValueIterator {
    966  public:
    967   EncodedStaticFieldValueIterator(const DexFile& dex_file,
    968                                   const dex::ClassDef& class_def)
    969       : EncodedArrayValueIterator(dex_file,
    970                                   dex_file.GetEncodedStaticFieldValuesArray(class_def))
    971   {}
    972 
    973  private:
    974   DISALLOW_IMPLICIT_CONSTRUCTORS(EncodedStaticFieldValueIterator);
    975 };
    976 std::ostream& operator<<(std::ostream& os, const EncodedStaticFieldValueIterator::ValueType& code);
    977 
    978 class CallSiteArrayValueIterator : public EncodedArrayValueIterator {
    979  public:
    980   CallSiteArrayValueIterator(const DexFile& dex_file,
    981                              const dex::CallSiteIdItem& call_site_id)
    982       : EncodedArrayValueIterator(dex_file,
    983                                   dex_file.GetCallSiteEncodedValuesArray(call_site_id))
    984   {}
    985 
    986   uint32_t Size() const { return array_size_; }
    987 
    988  private:
    989   DISALLOW_IMPLICIT_CONSTRUCTORS(CallSiteArrayValueIterator);
    990 };
    991 std::ostream& operator<<(std::ostream& os, const CallSiteArrayValueIterator::ValueType& code);
    992 
    993 }  // namespace art
    994 
    995 #endif  // ART_LIBDEXFILE_DEX_DEX_FILE_H_
    996