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      1 /*
      2  * Copyright (C) 2008 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 /*
     18  * Access .dex (Dalvik Executable Format) files.  The code here assumes that
     19  * the DEX file has been rewritten (byte-swapped, word-aligned) and that
     20  * the contents can be directly accessed as a collection of C arrays.  Please
     21  * see docs/dalvik/dex-format.html for a detailed description.
     22  *
     23  * The structure and field names were chosen to match those in the DEX spec.
     24  *
     25  * It's generally assumed that the DEX file will be stored in shared memory,
     26  * obviating the need to copy code and constant pool entries into newly
     27  * allocated storage.  Maintaining local pointers to items in the shared area
     28  * is valid and encouraged.
     29  *
     30  * All memory-mapped structures are 32-bit aligned unless otherwise noted.
     31  */
     32 
     33 #ifndef LIBDEX_DEXFILE_H_
     34 #define LIBDEX_DEXFILE_H_
     35 
     36 #ifndef LOG_TAG
     37 # define LOG_TAG "libdex"
     38 #endif
     39 
     40 #include <stdbool.h>
     41 #include <stdint.h>
     42 #include <stdio.h>
     43 #include <assert.h>
     44 #include "cutils/log.h"
     45 
     46 /*
     47  * If "very verbose" logging is enabled, make it equivalent to ALOGV.
     48  * Otherwise, make it disappear.
     49  *
     50  * Define this above the #include "Dalvik.h" to enable for only a
     51  * single file.
     52  */
     53 /* #define VERY_VERBOSE_LOG */
     54 #if defined(VERY_VERBOSE_LOG)
     55 # define LOGVV      ALOGV
     56 # define IF_LOGVV() IF_ALOGV()
     57 #else
     58 # define LOGVV(...) ((void)0)
     59 # define IF_LOGVV() if (false)
     60 #endif
     61 
     62 /*
     63  * These match the definitions in the VM specification.
     64  */
     65 typedef uint8_t             u1;
     66 typedef uint16_t            u2;
     67 typedef uint32_t            u4;
     68 typedef uint64_t            u8;
     69 typedef int8_t              s1;
     70 typedef int16_t             s2;
     71 typedef int32_t             s4;
     72 typedef int64_t             s8;
     73 
     74 #include "libdex/SysUtil.h"
     75 
     76 /*
     77  * gcc-style inline management -- ensures we have a copy of all functions
     78  * in the library, so code that links against us will work whether or not
     79  * it was built with optimizations enabled.
     80  */
     81 #ifndef _DEX_GEN_INLINES             /* only defined by DexInlines.c */
     82 # define DEX_INLINE extern __inline__
     83 #else
     84 # define DEX_INLINE
     85 #endif
     86 
     87 /* DEX file magic number */
     88 #define DEX_MAGIC       "dex\n"
     89 
     90 /* The version for android N, encoded in 4 bytes of ASCII. This differentiates dex files that may
     91  * use default methods.
     92  */
     93 #define DEX_MAGIC_VERS_37  "037\0"
     94 
     95 /* The version for android O, encoded in 4 bytes of ASCII. This differentiates dex files that may
     96  * contain invoke-custom, invoke-polymorphic, call-sites, and method handles.
     97  */
     98 #define DEX_MAGIC_VERS_38  "038\0"
     99 
    100 /* current version, encoded in 4 bytes of ASCII */
    101 #define DEX_MAGIC_VERS  "036\0"
    102 
    103 /*
    104  * older but still-recognized version (corresponding to Android API
    105  * levels 13 and earlier
    106  */
    107 #define DEX_MAGIC_VERS_API_13  "035\0"
    108 
    109 /* same, but for optimized DEX header */
    110 #define DEX_OPT_MAGIC   "dey\n"
    111 #define DEX_OPT_MAGIC_VERS  "036\0"
    112 
    113 #define DEX_DEP_MAGIC   "deps"
    114 
    115 /*
    116  * 160-bit SHA-1 digest.
    117  */
    118 enum { kSHA1DigestLen = 20,
    119        kSHA1DigestOutputLen = kSHA1DigestLen*2 +1 };
    120 
    121 /* general constants */
    122 enum {
    123     kDexEndianConstant = 0x12345678,    /* the endianness indicator */
    124     kDexNoIndex = 0xffffffff,           /* not a valid index value */
    125 };
    126 
    127 /*
    128  * Enumeration of all the primitive types.
    129  */
    130 enum PrimitiveType {
    131     PRIM_NOT        = 0,       /* value is a reference type, not a primitive type */
    132     PRIM_VOID       = 1,
    133     PRIM_BOOLEAN    = 2,
    134     PRIM_BYTE       = 3,
    135     PRIM_SHORT      = 4,
    136     PRIM_CHAR       = 5,
    137     PRIM_INT        = 6,
    138     PRIM_LONG       = 7,
    139     PRIM_FLOAT      = 8,
    140     PRIM_DOUBLE     = 9,
    141 };
    142 
    143 /*
    144  * access flags and masks; the "standard" ones are all <= 0x4000
    145  *
    146  * Note: There are related declarations in vm/oo/Object.h in the ClassFlags
    147  * enum.
    148  */
    149 enum {
    150     ACC_PUBLIC       = 0x00000001,       // class, field, method, ic
    151     ACC_PRIVATE      = 0x00000002,       // field, method, ic
    152     ACC_PROTECTED    = 0x00000004,       // field, method, ic
    153     ACC_STATIC       = 0x00000008,       // field, method, ic
    154     ACC_FINAL        = 0x00000010,       // class, field, method, ic
    155     ACC_SYNCHRONIZED = 0x00000020,       // method (only allowed on natives)
    156     ACC_SUPER        = 0x00000020,       // class (not used in Dalvik)
    157     ACC_VOLATILE     = 0x00000040,       // field
    158     ACC_BRIDGE       = 0x00000040,       // method (1.5)
    159     ACC_TRANSIENT    = 0x00000080,       // field
    160     ACC_VARARGS      = 0x00000080,       // method (1.5)
    161     ACC_NATIVE       = 0x00000100,       // method
    162     ACC_INTERFACE    = 0x00000200,       // class, ic
    163     ACC_ABSTRACT     = 0x00000400,       // class, method, ic
    164     ACC_STRICT       = 0x00000800,       // method
    165     ACC_SYNTHETIC    = 0x00001000,       // field, method, ic
    166     ACC_ANNOTATION   = 0x00002000,       // class, ic (1.5)
    167     ACC_ENUM         = 0x00004000,       // class, field, ic (1.5)
    168     ACC_CONSTRUCTOR  = 0x00010000,       // method (Dalvik only)
    169     ACC_DECLARED_SYNCHRONIZED =
    170                        0x00020000,       // method (Dalvik only)
    171     ACC_CLASS_MASK =
    172         (ACC_PUBLIC | ACC_FINAL | ACC_INTERFACE | ACC_ABSTRACT
    173                 | ACC_SYNTHETIC | ACC_ANNOTATION | ACC_ENUM),
    174     ACC_INNER_CLASS_MASK =
    175         (ACC_CLASS_MASK | ACC_PRIVATE | ACC_PROTECTED | ACC_STATIC),
    176     ACC_FIELD_MASK =
    177         (ACC_PUBLIC | ACC_PRIVATE | ACC_PROTECTED | ACC_STATIC | ACC_FINAL
    178                 | ACC_VOLATILE | ACC_TRANSIENT | ACC_SYNTHETIC | ACC_ENUM),
    179     ACC_METHOD_MASK =
    180         (ACC_PUBLIC | ACC_PRIVATE | ACC_PROTECTED | ACC_STATIC | ACC_FINAL
    181                 | ACC_SYNCHRONIZED | ACC_BRIDGE | ACC_VARARGS | ACC_NATIVE
    182                 | ACC_ABSTRACT | ACC_STRICT | ACC_SYNTHETIC | ACC_CONSTRUCTOR
    183                 | ACC_DECLARED_SYNCHRONIZED),
    184 };
    185 
    186 /* annotation constants */
    187 enum {
    188     kDexVisibilityBuild         = 0x00,     /* annotation visibility */
    189     kDexVisibilityRuntime       = 0x01,
    190     kDexVisibilitySystem        = 0x02,
    191 
    192     kDexAnnotationByte          = 0x00,
    193     kDexAnnotationShort         = 0x02,
    194     kDexAnnotationChar          = 0x03,
    195     kDexAnnotationInt           = 0x04,
    196     kDexAnnotationLong          = 0x06,
    197     kDexAnnotationFloat         = 0x10,
    198     kDexAnnotationDouble        = 0x11,
    199     kDexAnnotationMethodType    = 0x15,
    200     kDexAnnotationMethodHandle  = 0x16,
    201     kDexAnnotationString        = 0x17,
    202     kDexAnnotationType          = 0x18,
    203     kDexAnnotationField         = 0x19,
    204     kDexAnnotationMethod        = 0x1a,
    205     kDexAnnotationEnum          = 0x1b,
    206     kDexAnnotationArray         = 0x1c,
    207     kDexAnnotationAnnotation    = 0x1d,
    208     kDexAnnotationNull          = 0x1e,
    209     kDexAnnotationBoolean       = 0x1f,
    210 
    211     kDexAnnotationValueTypeMask = 0x1f,     /* low 5 bits */
    212     kDexAnnotationValueArgShift = 5,
    213 };
    214 
    215 /* map item type codes */
    216 enum {
    217     kDexTypeHeaderItem               = 0x0000,
    218     kDexTypeStringIdItem             = 0x0001,
    219     kDexTypeTypeIdItem               = 0x0002,
    220     kDexTypeProtoIdItem              = 0x0003,
    221     kDexTypeFieldIdItem              = 0x0004,
    222     kDexTypeMethodIdItem             = 0x0005,
    223     kDexTypeClassDefItem             = 0x0006,
    224     kDexTypeCallSiteIdItem           = 0x0007,
    225     kDexTypeMethodHandleItem         = 0x0008,
    226     kDexTypeMapList                  = 0x1000,
    227     kDexTypeTypeList                 = 0x1001,
    228     kDexTypeAnnotationSetRefList     = 0x1002,
    229     kDexTypeAnnotationSetItem        = 0x1003,
    230     kDexTypeClassDataItem            = 0x2000,
    231     kDexTypeCodeItem                 = 0x2001,
    232     kDexTypeStringDataItem           = 0x2002,
    233     kDexTypeDebugInfoItem            = 0x2003,
    234     kDexTypeAnnotationItem           = 0x2004,
    235     kDexTypeEncodedArrayItem         = 0x2005,
    236     kDexTypeAnnotationsDirectoryItem = 0x2006,
    237 };
    238 
    239 /* auxillary data section chunk codes */
    240 enum {
    241     kDexChunkClassLookup            = 0x434c4b50,   /* CLKP */
    242     kDexChunkRegisterMaps           = 0x524d4150,   /* RMAP */
    243 
    244     kDexChunkEnd                    = 0x41454e44,   /* AEND */
    245 };
    246 
    247 /* debug info opcodes and constants */
    248 enum {
    249     DBG_END_SEQUENCE         = 0x00,
    250     DBG_ADVANCE_PC           = 0x01,
    251     DBG_ADVANCE_LINE         = 0x02,
    252     DBG_START_LOCAL          = 0x03,
    253     DBG_START_LOCAL_EXTENDED = 0x04,
    254     DBG_END_LOCAL            = 0x05,
    255     DBG_RESTART_LOCAL        = 0x06,
    256     DBG_SET_PROLOGUE_END     = 0x07,
    257     DBG_SET_EPILOGUE_BEGIN   = 0x08,
    258     DBG_SET_FILE             = 0x09,
    259     DBG_FIRST_SPECIAL        = 0x0a,
    260     DBG_LINE_BASE            = -4,
    261     DBG_LINE_RANGE           = 15,
    262 };
    263 
    264 /*
    265  * Direct-mapped "header_item" struct.
    266  */
    267 struct DexHeader {
    268     u1  magic[8];           /* includes version number */
    269     u4  checksum;           /* adler32 checksum */
    270     u1  signature[kSHA1DigestLen]; /* SHA-1 hash */
    271     u4  fileSize;           /* length of entire file */
    272     u4  headerSize;         /* offset to start of next section */
    273     u4  endianTag;
    274     u4  linkSize;
    275     u4  linkOff;
    276     u4  mapOff;
    277     u4  stringIdsSize;
    278     u4  stringIdsOff;
    279     u4  typeIdsSize;
    280     u4  typeIdsOff;
    281     u4  protoIdsSize;
    282     u4  protoIdsOff;
    283     u4  fieldIdsSize;
    284     u4  fieldIdsOff;
    285     u4  methodIdsSize;
    286     u4  methodIdsOff;
    287     u4  classDefsSize;
    288     u4  classDefsOff;
    289     u4  dataSize;
    290     u4  dataOff;
    291 };
    292 
    293 /*
    294  * Direct-mapped "map_item".
    295  */
    296 struct DexMapItem {
    297     u2 type;              /* type code (see kDexType* above) */
    298     u2 unused;
    299     u4 size;              /* count of items of the indicated type */
    300     u4 offset;            /* file offset to the start of data */
    301 };
    302 
    303 /*
    304  * Direct-mapped "map_list".
    305  */
    306 struct DexMapList {
    307     u4  size;               /* #of entries in list */
    308     DexMapItem list[1];     /* entries */
    309 };
    310 
    311 /*
    312  * Direct-mapped "string_id_item".
    313  */
    314 struct DexStringId {
    315     u4 stringDataOff;      /* file offset to string_data_item */
    316 };
    317 
    318 /*
    319  * Direct-mapped "type_id_item".
    320  */
    321 struct DexTypeId {
    322     u4  descriptorIdx;      /* index into stringIds list for type descriptor */
    323 };
    324 
    325 /*
    326  * Direct-mapped "field_id_item".
    327  */
    328 struct DexFieldId {
    329     u2  classIdx;           /* index into typeIds list for defining class */
    330     u2  typeIdx;            /* index into typeIds for field type */
    331     u4  nameIdx;            /* index into stringIds for field name */
    332 };
    333 
    334 /*
    335  * Direct-mapped "method_id_item".
    336  */
    337 struct DexMethodId {
    338     u2  classIdx;           /* index into typeIds list for defining class */
    339     u2  protoIdx;           /* index into protoIds for method prototype */
    340     u4  nameIdx;            /* index into stringIds for method name */
    341 };
    342 
    343 /*
    344  * Direct-mapped "proto_id_item".
    345  */
    346 struct DexProtoId {
    347     u4  shortyIdx;          /* index into stringIds for shorty descriptor */
    348     u4  returnTypeIdx;      /* index into typeIds list for return type */
    349     u4  parametersOff;      /* file offset to type_list for parameter types */
    350 };
    351 
    352 /*
    353  * Direct-mapped "class_def_item".
    354  */
    355 struct DexClassDef {
    356     u4  classIdx;           /* index into typeIds for this class */
    357     u4  accessFlags;
    358     u4  superclassIdx;      /* index into typeIds for superclass */
    359     u4  interfacesOff;      /* file offset to DexTypeList */
    360     u4  sourceFileIdx;      /* index into stringIds for source file name */
    361     u4  annotationsOff;     /* file offset to annotations_directory_item */
    362     u4  classDataOff;       /* file offset to class_data_item */
    363     u4  staticValuesOff;    /* file offset to DexEncodedArray */
    364 };
    365 
    366 /*
    367  * Direct-mapped "call_site_id_item"
    368  */
    369 struct DexCallSiteId {
    370     u4  callSiteOff;        /* file offset to DexEncodedArray */
    371 };
    372 
    373 /*
    374  * Enumeration of method handle type codes.
    375  */
    376 enum MethodHandleType {
    377     STATIC_PUT = 0x00,
    378     STATIC_GET = 0x01,
    379     INSTANCE_PUT = 0x02,
    380     INSTANCE_GET = 0x03,
    381     INVOKE_STATIC = 0x04,
    382     INVOKE_INSTANCE = 0x05,
    383     INVOKE_CONSTRUCTOR = 0x06,
    384     INVOKE_DIRECT = 0x07,
    385     INVOKE_INTERFACE = 0x08
    386 };
    387 
    388 /*
    389  * Direct-mapped "method_handle_item"
    390  */
    391 struct DexMethodHandleItem {
    392     u2 methodHandleType;    /* type of method handle */
    393     u2 reserved1;           /* reserved for future use */
    394     u2 fieldOrMethodIdx;    /* index of associated field or method */
    395     u2 reserved2;           /* reserved for future use */
    396 };
    397 
    398 /*
    399  * Direct-mapped "type_item".
    400  */
    401 struct DexTypeItem {
    402     u2  typeIdx;            /* index into typeIds */
    403 };
    404 
    405 /*
    406  * Direct-mapped "type_list".
    407  */
    408 struct DexTypeList {
    409     u4  size;               /* #of entries in list */
    410     DexTypeItem list[1];    /* entries */
    411 };
    412 
    413 /*
    414  * Direct-mapped "code_item".
    415  *
    416  * The "catches" table is used when throwing an exception,
    417  * "debugInfo" is used when displaying an exception stack trace or
    418  * debugging. An offset of zero indicates that there are no entries.
    419  */
    420 struct DexCode {
    421     u2  registersSize;
    422     u2  insSize;
    423     u2  outsSize;
    424     u2  triesSize;
    425     u4  debugInfoOff;       /* file offset to debug info stream */
    426     u4  insnsSize;          /* size of the insns array, in u2 units */
    427     u2  insns[1];
    428     /* followed by optional u2 padding */
    429     /* followed by try_item[triesSize] */
    430     /* followed by uleb128 handlersSize */
    431     /* followed by catch_handler_item[handlersSize] */
    432 };
    433 
    434 /*
    435  * Direct-mapped "try_item".
    436  */
    437 struct DexTry {
    438     u4  startAddr;          /* start address, in 16-bit code units */
    439     u2  insnCount;          /* instruction count, in 16-bit code units */
    440     u2  handlerOff;         /* offset in encoded handler data to handlers */
    441 };
    442 
    443 /*
    444  * Link table.  Currently undefined.
    445  */
    446 struct DexLink {
    447     u1  bleargh;
    448 };
    449 
    450 
    451 /*
    452  * Direct-mapped "annotations_directory_item".
    453  */
    454 struct DexAnnotationsDirectoryItem {
    455     u4  classAnnotationsOff;  /* offset to DexAnnotationSetItem */
    456     u4  fieldsSize;           /* count of DexFieldAnnotationsItem */
    457     u4  methodsSize;          /* count of DexMethodAnnotationsItem */
    458     u4  parametersSize;       /* count of DexParameterAnnotationsItem */
    459     /* followed by DexFieldAnnotationsItem[fieldsSize] */
    460     /* followed by DexMethodAnnotationsItem[methodsSize] */
    461     /* followed by DexParameterAnnotationsItem[parametersSize] */
    462 };
    463 
    464 /*
    465  * Direct-mapped "field_annotations_item".
    466  */
    467 struct DexFieldAnnotationsItem {
    468     u4  fieldIdx;
    469     u4  annotationsOff;             /* offset to DexAnnotationSetItem */
    470 };
    471 
    472 /*
    473  * Direct-mapped "method_annotations_item".
    474  */
    475 struct DexMethodAnnotationsItem {
    476     u4  methodIdx;
    477     u4  annotationsOff;             /* offset to DexAnnotationSetItem */
    478 };
    479 
    480 /*
    481  * Direct-mapped "parameter_annotations_item".
    482  */
    483 struct DexParameterAnnotationsItem {
    484     u4  methodIdx;
    485     u4  annotationsOff;             /* offset to DexAnotationSetRefList */
    486 };
    487 
    488 /*
    489  * Direct-mapped "annotation_set_ref_item".
    490  */
    491 struct DexAnnotationSetRefItem {
    492     u4  annotationsOff;             /* offset to DexAnnotationSetItem */
    493 };
    494 
    495 /*
    496  * Direct-mapped "annotation_set_ref_list".
    497  */
    498 struct DexAnnotationSetRefList {
    499     u4  size;
    500     DexAnnotationSetRefItem list[1];
    501 };
    502 
    503 /*
    504  * Direct-mapped "annotation_set_item".
    505  */
    506 struct DexAnnotationSetItem {
    507     u4  size;
    508     u4  entries[1];                 /* offset to DexAnnotationItem */
    509 };
    510 
    511 /*
    512  * Direct-mapped "annotation_item".
    513  *
    514  * NOTE: this structure is byte-aligned.
    515  */
    516 struct DexAnnotationItem {
    517     u1  visibility;
    518     u1  annotation[1];              /* data in encoded_annotation format */
    519 };
    520 
    521 /*
    522  * Direct-mapped "encoded_array".
    523  *
    524  * NOTE: this structure is byte-aligned.
    525  */
    526 struct DexEncodedArray {
    527     u1  array[1];                   /* data in encoded_array format */
    528 };
    529 
    530 /*
    531  * Lookup table for classes.  It provides a mapping from class name to
    532  * class definition.  Used by dexFindClass().
    533  *
    534  * We calculate this at DEX optimization time and embed it in the file so we
    535  * don't need the same hash table in every VM.  This is slightly slower than
    536  * a hash table with direct pointers to the items, but because it's shared
    537  * there's less of a penalty for using a fairly sparse table.
    538  */
    539 struct DexClassLookup {
    540     int     size;                       // total size, including "size"
    541     int     numEntries;                 // size of table[]; always power of 2
    542     struct {
    543         u4      classDescriptorHash;    // class descriptor hash code
    544         int     classDescriptorOffset;  // in bytes, from start of DEX
    545         int     classDefOffset;         // in bytes, from start of DEX
    546     } table[1];
    547 };
    548 
    549 /*
    550  * Header added by DEX optimization pass.  Values are always written in
    551  * local byte and structure padding.  The first field (magic + version)
    552  * is guaranteed to be present and directly readable for all expected
    553  * compiler configurations; the rest is version-dependent.
    554  *
    555  * Try to keep this simple and fixed-size.
    556  */
    557 struct DexOptHeader {
    558     u1  magic[8];           /* includes version number */
    559 
    560     u4  dexOffset;          /* file offset of DEX header */
    561     u4  dexLength;
    562     u4  depsOffset;         /* offset of optimized DEX dependency table */
    563     u4  depsLength;
    564     u4  optOffset;          /* file offset of optimized data tables */
    565     u4  optLength;
    566 
    567     u4  flags;              /* some info flags */
    568     u4  checksum;           /* adler32 checksum covering deps/opt */
    569 
    570     /* pad for 64-bit alignment if necessary */
    571 };
    572 
    573 #define DEX_OPT_FLAG_BIG            (1<<1)  /* swapped to big-endian */
    574 
    575 #define DEX_INTERFACE_CACHE_SIZE    128     /* must be power of 2 */
    576 
    577 /*
    578  * Structure representing a DEX file.
    579  *
    580  * Code should regard DexFile as opaque, using the API calls provided here
    581  * to access specific structures.
    582  */
    583 struct DexFile {
    584     /* directly-mapped "opt" header */
    585     const DexOptHeader* pOptHeader;
    586 
    587     /* pointers to directly-mapped structs and arrays in base DEX */
    588     const DexHeader*    pHeader;
    589     const DexStringId*  pStringIds;
    590     const DexTypeId*    pTypeIds;
    591     const DexFieldId*   pFieldIds;
    592     const DexMethodId*  pMethodIds;
    593     const DexProtoId*   pProtoIds;
    594     const DexClassDef*  pClassDefs;
    595     const DexLink*      pLinkData;
    596 
    597     /*
    598      * These are mapped out of the "auxillary" section, and may not be
    599      * included in the file.
    600      */
    601     const DexClassLookup* pClassLookup;
    602     const void*         pRegisterMapPool;       // RegisterMapClassPool
    603 
    604     /* points to start of DEX file data */
    605     const u1*           baseAddr;
    606 
    607     /* track memory overhead for auxillary structures */
    608     int                 overhead;
    609 
    610     /* additional app-specific data structures associated with the DEX */
    611     //void*               auxData;
    612 };
    613 
    614 /*
    615  * Utility function -- rounds up to the nearest power of 2.
    616  */
    617 u4 dexRoundUpPower2(u4 val);
    618 
    619 /*
    620  * Parse an optimized or unoptimized .dex file sitting in memory.
    621  *
    622  * On success, return a newly-allocated DexFile.
    623  */
    624 DexFile* dexFileParse(const u1* data, size_t length, int flags);
    625 
    626 /* bit values for "flags" argument to dexFileParse */
    627 enum {
    628     kDexParseDefault            = 0,
    629     kDexParseVerifyChecksum     = 1,
    630     kDexParseContinueOnError    = (1 << 1),
    631 };
    632 
    633 /*
    634  * Fix the byte ordering of all fields in the DEX file, and do
    635  * structural verification. This is only required for code that opens
    636  * "raw" DEX files, such as the DEX optimizer.
    637  *
    638  * Return 0 on success.
    639  */
    640 int dexSwapAndVerify(u1* addr, int len);
    641 
    642 /*
    643  * Detect the file type of the given memory buffer via magic number.
    644  * Call dexSwapAndVerify() on an unoptimized DEX file, do nothing
    645  * but return successfully on an optimized DEX file, and report an
    646  * error for all other cases.
    647  *
    648  * Return 0 on success.
    649  */
    650 int dexSwapAndVerifyIfNecessary(u1* addr, size_t len);
    651 
    652 /*
    653  * Check to see if the file magic and format version in the given
    654  * header are recognized as valid. Returns true if they are
    655  * acceptable.
    656  */
    657 bool dexHasValidMagic(const DexHeader* pHeader);
    658 
    659 /*
    660  * Compute DEX checksum.
    661  */
    662 u4 dexComputeChecksum(const DexHeader* pHeader);
    663 
    664 /*
    665  * Free a DexFile structure, along with any associated structures.
    666  */
    667 void dexFileFree(DexFile* pDexFile);
    668 
    669 /*
    670  * Create class lookup table.
    671  */
    672 DexClassLookup* dexCreateClassLookup(DexFile* pDexFile);
    673 
    674 /*
    675  * Find a class definition by descriptor.
    676  */
    677 const DexClassDef* dexFindClass(const DexFile* pFile, const char* descriptor);
    678 
    679 /*
    680  * Set up the basic raw data pointers of a DexFile. This function isn't
    681  * meant for general use.
    682  */
    683 void dexFileSetupBasicPointers(DexFile* pDexFile, const u1* data);
    684 
    685 /* return the DexMapList of the file, if any */
    686 DEX_INLINE const DexMapList* dexGetMap(const DexFile* pDexFile) {
    687     u4 mapOff = pDexFile->pHeader->mapOff;
    688 
    689     if (mapOff == 0) {
    690         return NULL;
    691     } else {
    692         return (const DexMapList*) (pDexFile->baseAddr + mapOff);
    693     }
    694 }
    695 
    696 /* return the const char* string data referred to by the given string_id */
    697 DEX_INLINE const char* dexGetStringData(const DexFile* pDexFile,
    698         const DexStringId* pStringId) {
    699     const u1* ptr = pDexFile->baseAddr + pStringId->stringDataOff;
    700 
    701     // Skip the uleb128 length.
    702     while (*(ptr++) > 0x7f) /* empty */ ;
    703 
    704     return (const char*) ptr;
    705 }
    706 /* return the StringId with the specified index */
    707 DEX_INLINE const DexStringId* dexGetStringId(const DexFile* pDexFile, u4 idx) {
    708     assert(idx < pDexFile->pHeader->stringIdsSize);
    709     return &pDexFile->pStringIds[idx];
    710 }
    711 /* return the UTF-8 encoded string with the specified string_id index */
    712 DEX_INLINE const char* dexStringById(const DexFile* pDexFile, u4 idx) {
    713     const DexStringId* pStringId = dexGetStringId(pDexFile, idx);
    714     return dexGetStringData(pDexFile, pStringId);
    715 }
    716 
    717 /* Return the UTF-8 encoded string with the specified string_id index,
    718  * also filling in the UTF-16 size (number of 16-bit code points).*/
    719 const char* dexStringAndSizeById(const DexFile* pDexFile, u4 idx,
    720         u4* utf16Size);
    721 
    722 /* return the TypeId with the specified index */
    723 DEX_INLINE const DexTypeId* dexGetTypeId(const DexFile* pDexFile, u4 idx) {
    724     assert(idx < pDexFile->pHeader->typeIdsSize);
    725     return &pDexFile->pTypeIds[idx];
    726 }
    727 
    728 /*
    729  * Get the descriptor string associated with a given type index.
    730  * The caller should not free() the returned string.
    731  */
    732 DEX_INLINE const char* dexStringByTypeIdx(const DexFile* pDexFile, u4 idx) {
    733     const DexTypeId* typeId = dexGetTypeId(pDexFile, idx);
    734     return dexStringById(pDexFile, typeId->descriptorIdx);
    735 }
    736 
    737 /* return the MethodId with the specified index */
    738 DEX_INLINE const DexMethodId* dexGetMethodId(const DexFile* pDexFile, u4 idx) {
    739     assert(idx < pDexFile->pHeader->methodIdsSize);
    740     return &pDexFile->pMethodIds[idx];
    741 }
    742 
    743 /* return the FieldId with the specified index */
    744 DEX_INLINE const DexFieldId* dexGetFieldId(const DexFile* pDexFile, u4 idx) {
    745     assert(idx < pDexFile->pHeader->fieldIdsSize);
    746     return &pDexFile->pFieldIds[idx];
    747 }
    748 
    749 /* return the ProtoId with the specified index */
    750 DEX_INLINE const DexProtoId* dexGetProtoId(const DexFile* pDexFile, u4 idx) {
    751     assert(idx < pDexFile->pHeader->protoIdsSize);
    752     return &pDexFile->pProtoIds[idx];
    753 }
    754 
    755 /*
    756  * Get the parameter list from a ProtoId. The returns NULL if the ProtoId
    757  * does not have a parameter list.
    758  */
    759 DEX_INLINE const DexTypeList* dexGetProtoParameters(
    760     const DexFile *pDexFile, const DexProtoId* pProtoId) {
    761     if (pProtoId->parametersOff == 0) {
    762         return NULL;
    763     }
    764     return (const DexTypeList*)
    765         (pDexFile->baseAddr + pProtoId->parametersOff);
    766 }
    767 
    768 /* return the ClassDef with the specified index */
    769 DEX_INLINE const DexClassDef* dexGetClassDef(const DexFile* pDexFile, u4 idx) {
    770     assert(idx < pDexFile->pHeader->classDefsSize);
    771     return &pDexFile->pClassDefs[idx];
    772 }
    773 
    774 /* given a ClassDef pointer, recover its index */
    775 DEX_INLINE u4 dexGetIndexForClassDef(const DexFile* pDexFile,
    776     const DexClassDef* pClassDef)
    777 {
    778     assert(pClassDef >= pDexFile->pClassDefs &&
    779            pClassDef < pDexFile->pClassDefs + pDexFile->pHeader->classDefsSize);
    780     return pClassDef - pDexFile->pClassDefs;
    781 }
    782 
    783 /* get the interface list for a DexClass */
    784 DEX_INLINE const DexTypeList* dexGetInterfacesList(const DexFile* pDexFile,
    785     const DexClassDef* pClassDef)
    786 {
    787     if (pClassDef->interfacesOff == 0)
    788         return NULL;
    789     return (const DexTypeList*)
    790         (pDexFile->baseAddr + pClassDef->interfacesOff);
    791 }
    792 /* return the Nth entry in a DexTypeList. */
    793 DEX_INLINE const DexTypeItem* dexGetTypeItem(const DexTypeList* pList,
    794     u4 idx)
    795 {
    796     assert(idx < pList->size);
    797     return &pList->list[idx];
    798 }
    799 /* return the type_idx for the Nth entry in a TypeList */
    800 DEX_INLINE u4 dexTypeListGetIdx(const DexTypeList* pList, u4 idx) {
    801     const DexTypeItem* pItem = dexGetTypeItem(pList, idx);
    802     return pItem->typeIdx;
    803 }
    804 
    805 /* get the static values list for a DexClass */
    806 DEX_INLINE const DexEncodedArray* dexGetStaticValuesList(
    807     const DexFile* pDexFile, const DexClassDef* pClassDef)
    808 {
    809     if (pClassDef->staticValuesOff == 0)
    810         return NULL;
    811     return (const DexEncodedArray*)
    812         (pDexFile->baseAddr + pClassDef->staticValuesOff);
    813 }
    814 
    815 /* get the annotations directory item for a DexClass */
    816 DEX_INLINE const DexAnnotationsDirectoryItem* dexGetAnnotationsDirectoryItem(
    817     const DexFile* pDexFile, const DexClassDef* pClassDef)
    818 {
    819     if (pClassDef->annotationsOff == 0)
    820         return NULL;
    821     return (const DexAnnotationsDirectoryItem*)
    822         (pDexFile->baseAddr + pClassDef->annotationsOff);
    823 }
    824 
    825 /* get the source file string */
    826 DEX_INLINE const char* dexGetSourceFile(
    827     const DexFile* pDexFile, const DexClassDef* pClassDef)
    828 {
    829     if (pClassDef->sourceFileIdx == 0xffffffff)
    830         return NULL;
    831     return dexStringById(pDexFile, pClassDef->sourceFileIdx);
    832 }
    833 
    834 /* get the size, in bytes, of a DexCode */
    835 size_t dexGetDexCodeSize(const DexCode* pCode);
    836 
    837 /* Get the list of "tries" for the given DexCode. */
    838 DEX_INLINE const DexTry* dexGetTries(const DexCode* pCode) {
    839     const u2* insnsEnd = &pCode->insns[pCode->insnsSize];
    840 
    841     // Round to four bytes.
    842     if ((((uintptr_t) insnsEnd) & 3) != 0) {
    843         insnsEnd++;
    844     }
    845 
    846     return (const DexTry*) insnsEnd;
    847 }
    848 
    849 /* Get the base of the encoded data for the given DexCode. */
    850 DEX_INLINE const u1* dexGetCatchHandlerData(const DexCode* pCode) {
    851     const DexTry* pTries = dexGetTries(pCode);
    852     return (const u1*) &pTries[pCode->triesSize];
    853 }
    854 
    855 /* get a pointer to the start of the debugging data */
    856 DEX_INLINE const u1* dexGetDebugInfoStream(const DexFile* pDexFile,
    857     const DexCode* pCode)
    858 {
    859     if (pCode->debugInfoOff == 0) {
    860         return NULL;
    861     } else {
    862         return pDexFile->baseAddr + pCode->debugInfoOff;
    863     }
    864 }
    865 
    866 /* DexClassDef convenience - get class descriptor */
    867 DEX_INLINE const char* dexGetClassDescriptor(const DexFile* pDexFile,
    868     const DexClassDef* pClassDef)
    869 {
    870     return dexStringByTypeIdx(pDexFile, pClassDef->classIdx);
    871 }
    872 
    873 /* DexClassDef convenience - get superclass descriptor */
    874 DEX_INLINE const char* dexGetSuperClassDescriptor(const DexFile* pDexFile,
    875     const DexClassDef* pClassDef)
    876 {
    877     if (pClassDef->superclassIdx == 0)
    878         return NULL;
    879     return dexStringByTypeIdx(pDexFile, pClassDef->superclassIdx);
    880 }
    881 
    882 /* DexClassDef convenience - get class_data_item pointer */
    883 DEX_INLINE const u1* dexGetClassData(const DexFile* pDexFile,
    884     const DexClassDef* pClassDef)
    885 {
    886     if (pClassDef->classDataOff == 0)
    887         return NULL;
    888     return (const u1*) (pDexFile->baseAddr + pClassDef->classDataOff);
    889 }
    890 
    891 /* Get an annotation set at a particular offset. */
    892 DEX_INLINE const DexAnnotationSetItem* dexGetAnnotationSetItem(
    893     const DexFile* pDexFile, u4 offset)
    894 {
    895     if (offset == 0) {
    896         return NULL;
    897     }
    898     return (const DexAnnotationSetItem*) (pDexFile->baseAddr + offset);
    899 }
    900 /* get the class' annotation set */
    901 DEX_INLINE const DexAnnotationSetItem* dexGetClassAnnotationSet(
    902     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    903 {
    904     return dexGetAnnotationSetItem(pDexFile, pAnnoDir->classAnnotationsOff);
    905 }
    906 
    907 /* get the class' field annotation list */
    908 DEX_INLINE const DexFieldAnnotationsItem* dexGetFieldAnnotations(
    909     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    910 {
    911     (void) pDexFile;
    912     if (pAnnoDir->fieldsSize == 0)
    913         return NULL;
    914 
    915     // Skip past the header to the start of the field annotations.
    916     return (const DexFieldAnnotationsItem*) &pAnnoDir[1];
    917 }
    918 
    919 /* get field annotation list size */
    920 DEX_INLINE int dexGetFieldAnnotationsSize(const DexFile* pDexFile,
    921     const DexAnnotationsDirectoryItem* pAnnoDir)
    922 {
    923     (void) pDexFile;
    924     return pAnnoDir->fieldsSize;
    925 }
    926 
    927 /* return a pointer to the field's annotation set */
    928 DEX_INLINE const DexAnnotationSetItem* dexGetFieldAnnotationSetItem(
    929     const DexFile* pDexFile, const DexFieldAnnotationsItem* pItem)
    930 {
    931     return dexGetAnnotationSetItem(pDexFile, pItem->annotationsOff);
    932 }
    933 
    934 /* get the class' method annotation list */
    935 DEX_INLINE const DexMethodAnnotationsItem* dexGetMethodAnnotations(
    936     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    937 {
    938     (void) pDexFile;
    939     if (pAnnoDir->methodsSize == 0)
    940         return NULL;
    941 
    942     /*
    943      * Skip past the header and field annotations to the start of the
    944      * method annotations.
    945      */
    946     const u1* addr = (const u1*) &pAnnoDir[1];
    947     addr += pAnnoDir->fieldsSize * sizeof (DexFieldAnnotationsItem);
    948     return (const DexMethodAnnotationsItem*) addr;
    949 }
    950 
    951 /* get method annotation list size */
    952 DEX_INLINE int dexGetMethodAnnotationsSize(const DexFile* pDexFile,
    953     const DexAnnotationsDirectoryItem* pAnnoDir)
    954 {
    955     (void) pDexFile;
    956     return pAnnoDir->methodsSize;
    957 }
    958 
    959 /* return a pointer to the method's annotation set */
    960 DEX_INLINE const DexAnnotationSetItem* dexGetMethodAnnotationSetItem(
    961     const DexFile* pDexFile, const DexMethodAnnotationsItem* pItem)
    962 {
    963     return dexGetAnnotationSetItem(pDexFile, pItem->annotationsOff);
    964 }
    965 
    966 /* get the class' parameter annotation list */
    967 DEX_INLINE const DexParameterAnnotationsItem* dexGetParameterAnnotations(
    968     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    969 {
    970     (void) pDexFile;
    971     if (pAnnoDir->parametersSize == 0)
    972         return NULL;
    973 
    974     /*
    975      * Skip past the header, field annotations, and method annotations
    976      * to the start of the parameter annotations.
    977      */
    978     const u1* addr = (const u1*) &pAnnoDir[1];
    979     addr += pAnnoDir->fieldsSize * sizeof (DexFieldAnnotationsItem);
    980     addr += pAnnoDir->methodsSize * sizeof (DexMethodAnnotationsItem);
    981     return (const DexParameterAnnotationsItem*) addr;
    982 }
    983 
    984 /* get method annotation list size */
    985 DEX_INLINE int dexGetParameterAnnotationsSize(const DexFile* pDexFile,
    986     const DexAnnotationsDirectoryItem* pAnnoDir)
    987 {
    988     (void) pDexFile;
    989     return pAnnoDir->parametersSize;
    990 }
    991 
    992 /* return the parameter annotation ref list */
    993 DEX_INLINE const DexAnnotationSetRefList* dexGetParameterAnnotationSetRefList(
    994     const DexFile* pDexFile, const DexParameterAnnotationsItem* pItem)
    995 {
    996     if (pItem->annotationsOff == 0) {
    997         return NULL;
    998     }
    999     return (const DexAnnotationSetRefList*) (pDexFile->baseAddr + pItem->annotationsOff);
   1000 }
   1001 
   1002 /* get method annotation list size */
   1003 DEX_INLINE int dexGetParameterAnnotationSetRefSize(const DexFile* pDexFile,
   1004     const DexParameterAnnotationsItem* pItem)
   1005 {
   1006     if (pItem->annotationsOff == 0) {
   1007         return 0;
   1008     }
   1009     return dexGetParameterAnnotationSetRefList(pDexFile, pItem)->size;
   1010 }
   1011 
   1012 /* return the Nth entry from an annotation set ref list */
   1013 DEX_INLINE const DexAnnotationSetRefItem* dexGetParameterAnnotationSetRef(
   1014     const DexAnnotationSetRefList* pList, u4 idx)
   1015 {
   1016     assert(idx < pList->size);
   1017     return &pList->list[idx];
   1018 }
   1019 
   1020 /* given a DexAnnotationSetRefItem, return the DexAnnotationSetItem */
   1021 DEX_INLINE const DexAnnotationSetItem* dexGetSetRefItemItem(
   1022     const DexFile* pDexFile, const DexAnnotationSetRefItem* pItem)
   1023 {
   1024     return dexGetAnnotationSetItem(pDexFile, pItem->annotationsOff);
   1025 }
   1026 
   1027 /* return the Nth annotation offset from a DexAnnotationSetItem */
   1028 DEX_INLINE u4 dexGetAnnotationOff(
   1029     const DexAnnotationSetItem* pAnnoSet, u4 idx)
   1030 {
   1031     assert(idx < pAnnoSet->size);
   1032     return pAnnoSet->entries[idx];
   1033 }
   1034 
   1035 /* return the Nth annotation item from a DexAnnotationSetItem */
   1036 DEX_INLINE const DexAnnotationItem* dexGetAnnotationItem(
   1037     const DexFile* pDexFile, const DexAnnotationSetItem* pAnnoSet, u4 idx)
   1038 {
   1039     u4 offset = dexGetAnnotationOff(pAnnoSet, idx);
   1040     if (offset == 0) {
   1041         return NULL;
   1042     }
   1043     return (const DexAnnotationItem*) (pDexFile->baseAddr + offset);
   1044 }
   1045 
   1046 /*
   1047  * Get the type descriptor character associated with a given primitive
   1048  * type. This returns '\0' if the type is invalid.
   1049  */
   1050 char dexGetPrimitiveTypeDescriptorChar(PrimitiveType type);
   1051 
   1052 /*
   1053  * Get the type descriptor string associated with a given primitive
   1054  * type.
   1055  */
   1056 const char* dexGetPrimitiveTypeDescriptor(PrimitiveType type);
   1057 
   1058 /*
   1059  * Get the boxed type descriptor string associated with a given
   1060  * primitive type. This returns NULL for an invalid type, including
   1061  * particularly for type "void". In the latter case, even though there
   1062  * is a class Void, there's no such thing as a boxed instance of it.
   1063  */
   1064 const char* dexGetBoxedTypeDescriptor(PrimitiveType type);
   1065 
   1066 /*
   1067  * Get the primitive type constant from the given descriptor character.
   1068  * This returns PRIM_NOT (note: this is a 0) if the character is invalid
   1069  * as a primitive type descriptor.
   1070  */
   1071 PrimitiveType dexGetPrimitiveTypeFromDescriptorChar(char descriptorChar);
   1072 
   1073 #endif  // LIBDEX_DEXFILE_H_
   1074