1//===- Archive.h - ar archive file format -----------------------*- 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 ar archive file format class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_OBJECT_ARCHIVE_H
15#define LLVM_OBJECT_ARCHIVE_H
16
17#include "llvm/ADT/StringRef.h"
18#include "llvm/ADT/iterator_range.h"
19#include "llvm/Object/Binary.h"
20#include "llvm/Support/ErrorHandling.h"
21#include "llvm/Support/ErrorOr.h"
22#include "llvm/Support/FileSystem.h"
23#include "llvm/Support/MemoryBuffer.h"
24
25namespace llvm {
26namespace object {
27struct ArchiveMemberHeader {
28  char Name[16];
29  char LastModified[12];
30  char UID[6];
31  char GID[6];
32  char AccessMode[8];
33  char Size[10]; ///< Size of data, not including header or padding.
34  char Terminator[2];
35
36  /// Get the name without looking up long names.
37  llvm::StringRef getName() const;
38
39  /// Members are not larger than 4GB.
40  ErrorOr<uint32_t> getSize() const;
41
42  sys::fs::perms getAccessMode() const;
43  sys::TimeValue getLastModified() const;
44  llvm::StringRef getRawLastModified() const {
45    return StringRef(LastModified, sizeof(LastModified)).rtrim(" ");
46  }
47  unsigned getUID() const;
48  unsigned getGID() const;
49};
50
51class Archive : public Binary {
52  virtual void anchor();
53public:
54  class Child {
55    friend Archive;
56    const Archive *Parent;
57    /// \brief Includes header but not padding byte.
58    StringRef Data;
59    /// \brief Offset from Data to the start of the file.
60    uint16_t StartOfFile;
61
62    const ArchiveMemberHeader *getHeader() const {
63      return reinterpret_cast<const ArchiveMemberHeader *>(Data.data());
64    }
65
66    bool isThinMember() const;
67
68  public:
69    Child(const Archive *Parent, const char *Start, std::error_code *EC);
70    Child(const Archive *Parent, StringRef Data, uint16_t StartOfFile);
71
72    bool operator ==(const Child &other) const {
73      assert(Parent == other.Parent);
74      return Data.begin() == other.Data.begin();
75    }
76
77    const Archive *getParent() const { return Parent; }
78    ErrorOr<Child> getNext() const;
79
80    ErrorOr<StringRef> getName() const;
81    StringRef getRawName() const { return getHeader()->getName(); }
82    sys::TimeValue getLastModified() const {
83      return getHeader()->getLastModified();
84    }
85    StringRef getRawLastModified() const {
86      return getHeader()->getRawLastModified();
87    }
88    unsigned getUID() const { return getHeader()->getUID(); }
89    unsigned getGID() const { return getHeader()->getGID(); }
90    sys::fs::perms getAccessMode() const {
91      return getHeader()->getAccessMode();
92    }
93    /// \return the size of the archive member without the header or padding.
94    ErrorOr<uint64_t> getSize() const;
95    /// \return the size in the archive header for this member.
96    ErrorOr<uint64_t> getRawSize() const;
97
98    ErrorOr<StringRef> getBuffer() const;
99    uint64_t getChildOffset() const;
100
101    ErrorOr<MemoryBufferRef> getMemoryBufferRef() const;
102
103    ErrorOr<std::unique_ptr<Binary>>
104    getAsBinary(LLVMContext *Context = nullptr) const;
105  };
106
107  class child_iterator {
108    ErrorOr<Child> child;
109
110  public:
111    child_iterator() : child(Child(nullptr, nullptr, nullptr)) {}
112    child_iterator(const Child &c) : child(c) {}
113    child_iterator(std::error_code EC) : child(EC) {}
114    const ErrorOr<Child> *operator->() const { return &child; }
115    const ErrorOr<Child> &operator*() const { return child; }
116
117    bool operator==(const child_iterator &other) const {
118      // We ignore error states so that comparisions with end() work, which
119      // allows range loops.
120      if (child.getError() || other.child.getError())
121        return false;
122      return *child == *other.child;
123    }
124
125    bool operator!=(const child_iterator &other) const {
126      return !(*this == other);
127    }
128
129    // Code in loops with child_iterators must check for errors on each loop
130    // iteration.  And if there is an error break out of the loop.
131    child_iterator &operator++() { // Preincrement
132      assert(child && "Can't increment iterator with error");
133      child = child->getNext();
134      return *this;
135    }
136  };
137
138  class Symbol {
139    const Archive *Parent;
140    uint32_t SymbolIndex;
141    uint32_t StringIndex; // Extra index to the string.
142
143  public:
144    bool operator ==(const Symbol &other) const {
145      return (Parent == other.Parent) && (SymbolIndex == other.SymbolIndex);
146    }
147
148    Symbol(const Archive *p, uint32_t symi, uint32_t stri)
149      : Parent(p)
150      , SymbolIndex(symi)
151      , StringIndex(stri) {}
152    StringRef getName() const;
153    ErrorOr<Child> getMember() const;
154    Symbol getNext() const;
155  };
156
157  class symbol_iterator {
158    Symbol symbol;
159  public:
160    symbol_iterator(const Symbol &s) : symbol(s) {}
161    const Symbol *operator->() const { return &symbol; }
162    const Symbol &operator*() const { return symbol; }
163
164    bool operator==(const symbol_iterator &other) const {
165      return symbol == other.symbol;
166    }
167
168    bool operator!=(const symbol_iterator &other) const {
169      return !(*this == other);
170    }
171
172    symbol_iterator& operator++() {  // Preincrement
173      symbol = symbol.getNext();
174      return *this;
175    }
176  };
177
178  Archive(MemoryBufferRef Source, std::error_code &EC);
179  static ErrorOr<std::unique_ptr<Archive>> create(MemoryBufferRef Source);
180
181  enum Kind {
182    K_GNU,
183    K_MIPS64,
184    K_BSD,
185    K_COFF
186  };
187
188  Kind kind() const { return (Kind)Format; }
189  bool isThin() const { return IsThin; }
190
191  child_iterator child_begin(bool SkipInternal = true) const;
192  child_iterator child_end() const;
193  iterator_range<child_iterator> children(bool SkipInternal = true) const {
194    return make_range(child_begin(SkipInternal), child_end());
195  }
196
197  symbol_iterator symbol_begin() const;
198  symbol_iterator symbol_end() const;
199  iterator_range<symbol_iterator> symbols() const {
200    return make_range(symbol_begin(), symbol_end());
201  }
202
203  // Cast methods.
204  static inline bool classof(Binary const *v) {
205    return v->isArchive();
206  }
207
208  // check if a symbol is in the archive
209  child_iterator findSym(StringRef name) const;
210
211  bool hasSymbolTable() const;
212  StringRef getSymbolTable() const { return SymbolTable; }
213  uint32_t getNumberOfSymbols() const;
214
215private:
216  StringRef SymbolTable;
217  StringRef StringTable;
218
219  StringRef FirstRegularData;
220  uint16_t FirstRegularStartOfFile = -1;
221  void setFirstRegular(const Child &C);
222
223  unsigned Format : 2;
224  unsigned IsThin : 1;
225  mutable std::vector<std::unique_ptr<MemoryBuffer>> ThinBuffers;
226};
227
228}
229}
230
231#endif
232