src/llvm/include/llvm/Object/SymbolicFile.h

   1 //===- SymbolicFile.h - Interface that only provides symbols ----*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file declares the SymbolicFile interface.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_OBJECT_SYMBOLICFILE_H
  15 #define LLVM_OBJECT_SYMBOLICFILE_H
  16
  17 #include "llvm/Object/Binary.h"
  18
  19 namespace llvm {
  20 namespace object {
  21
  22 union DataRefImpl {
  23   // This entire union should probably be a
  24   // char[max(8, sizeof(uintptr_t))] and require the impl to cast.
  25   struct {
  26     uint32_t a, b;
  27   } d;
  28   uintptr_t p;
  29   DataRefImpl() { std::memset(this, 0, sizeof(DataRefImpl)); }
  30 };
  31
  32 inline bool operator==(const DataRefImpl &a, const DataRefImpl &b) {
  33   // Check bitwise identical. This is the only legal way to compare a union w/o
  34   // knowing which member is in use.
  35   return std::memcmp(&a, &b, sizeof(DataRefImpl)) == 0;
  36 }
  37
  38 inline bool operator!=(const DataRefImpl &a, const DataRefImpl &b) {
  39   return !operator==(a, b);
  40 }
  41
  42 inline bool operator<(const DataRefImpl &a, const DataRefImpl &b) {
  43   // Check bitwise identical. This is the only legal way to compare a union w/o
  44   // knowing which member is in use.
  45   return std::memcmp(&a, &b, sizeof(DataRefImpl)) < 0;
  46 }
  47
  48 template <class content_type> class content_iterator {
  49   content_type Current;
  50
  51 public:
  52   content_iterator(content_type symb) : Current(symb) {}
  53
  54   const content_type *operator->() const { return &Current; }
  55
  56   const content_type &operator*() const { return Current; }
  57
  58   bool operator==(const content_iterator &other) const {
  59     return Current == other.Current;
  60   }
  61
  62   bool operator!=(const content_iterator &other) const {
  63     return !(*this == other);
  64   }
  65
  66   content_iterator &operator++() { // preincrement
  67     Current.moveNext();
  68     return *this;
  69   }
  70 };
  71
  72 class SymbolicFile;
  73
  74 /// This is a value type class that represents a single symbol in the list of
  75 /// symbols in the object file.
  76 class BasicSymbolRef {
  77   DataRefImpl SymbolPimpl;
  78   const SymbolicFile *OwningObject;
  79
  80 public:
  81   // FIXME: should we add a SF_Text?
  82   enum Flags : unsigned {
  83     SF_None = 0,
  84     SF_Undefined = 1U << 0,      // Symbol is defined in another object file
  85     SF_Global = 1U << 1,         // Global symbol
  86     SF_Weak = 1U << 2,           // Weak symbol
  87     SF_Absolute = 1U << 3,       // Absolute symbol
  88     SF_Common = 1U << 4,         // Symbol has common linkage
  89     SF_Indirect = 1U << 5,       // Symbol is an alias to another symbol
  90     SF_FormatSpecific = 1U << 6, // Specific to the object file format
  91                                  // (e.g. section symbols)
  92     SF_Thumb = 1U << 7           // Thumb symbol in a 32-bit ARM binary
  93   };
  94
  95   BasicSymbolRef() : OwningObject(nullptr) { }
  96   BasicSymbolRef(DataRefImpl SymbolP, const SymbolicFile *Owner);
  97
  98   bool operator==(const BasicSymbolRef &Other) const;
  99   bool operator<(const BasicSymbolRef &Other) const;
 100
 101   void moveNext();
 102
 103   std::error_code printName(raw_ostream &OS) const;
 104
 105   /// Get symbol flags (bitwise OR of SymbolRef::Flags)
 106   uint32_t getFlags() const;
 107
 108   DataRefImpl getRawDataRefImpl() const;
 109   const SymbolicFile *getObject() const;
 110 };
 111
 112 typedef content_iterator<BasicSymbolRef> basic_symbol_iterator;
 113
 114 const uint64_t UnknownAddressOrSize = ~0ULL;
 115
 116 class SymbolicFile : public Binary {
 117 public:
 118   virtual ~SymbolicFile();
 119   SymbolicFile(unsigned int Type, MemoryBufferRef Source);
 120
 121   // virtual interface.
 122   virtual void moveSymbolNext(DataRefImpl &Symb) const = 0;
 123
 124   virtual std::error_code printSymbolName(raw_ostream &OS,
 125                                           DataRefImpl Symb) const = 0;
 126
 127   virtual uint32_t getSymbolFlags(DataRefImpl Symb) const = 0;
 128
 129   virtual basic_symbol_iterator symbol_begin_impl() const = 0;
 130
 131   virtual basic_symbol_iterator symbol_end_impl() const = 0;
 132
 133   // convenience wrappers.
 134   basic_symbol_iterator symbol_begin() const {
 135     return symbol_begin_impl();
 136   }
 137   basic_symbol_iterator symbol_end() const {
 138     return symbol_end_impl();
 139   }
 140   typedef iterator_range<basic_symbol_iterator> basic_symbol_iterator_range;
 141   basic_symbol_iterator_range symbols() const {
 142     return basic_symbol_iterator_range(symbol_begin(), symbol_end());
 143   }
 144
 145   // construction aux.
 146   static ErrorOr<std::unique_ptr<SymbolicFile>>
 147   createSymbolicFile(MemoryBufferRef Object, sys::fs::file_magic Type,
 148                      LLVMContext *Context);
 149
 150   static ErrorOr<std::unique_ptr<SymbolicFile>>
 151   createSymbolicFile(MemoryBufferRef Object) {
 152     return createSymbolicFile(Object, sys::fs::file_magic::unknown, nullptr);
 153   }
 154   static ErrorOr<OwningBinary<SymbolicFile>>
 155   createSymbolicFile(StringRef ObjectPath);
 156
 157   static inline bool classof(const Binary *v) {
 158     return v->isSymbolic();
 159   }
 160 };
 161
 162 inline BasicSymbolRef::BasicSymbolRef(DataRefImpl SymbolP,
 163                                       const SymbolicFile *Owner)
 164     : SymbolPimpl(SymbolP), OwningObject(Owner) {}
 165
 166 inline bool BasicSymbolRef::operator==(const BasicSymbolRef &Other) const {
 167   return SymbolPimpl == Other.SymbolPimpl;
 168 }
 169
 170 inline bool BasicSymbolRef::operator<(const BasicSymbolRef &Other) const {
 171   return SymbolPimpl < Other.SymbolPimpl;
 172 }
 173
 174 inline void BasicSymbolRef::moveNext() {
 175   return OwningObject->moveSymbolNext(SymbolPimpl);
 176 }
 177
 178 inline std::error_code BasicSymbolRef::printName(raw_ostream &OS) const {
 179   return OwningObject->printSymbolName(OS, SymbolPimpl);
 180 }
 181
 182 inline uint32_t BasicSymbolRef::getFlags() const {
 183   return OwningObject->getSymbolFlags(SymbolPimpl);
 184 }
 185
 186 inline DataRefImpl BasicSymbolRef::getRawDataRefImpl() const {
 187   return SymbolPimpl;
 188 }
 189
 190 inline const SymbolicFile *BasicSymbolRef::getObject() const {
 191   return OwningObject;
 192 }
 193
 194 }
 195 }
 196
 197 #endif