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/Optional.h"
18#include "llvm/ADT/StringRef.h"
19#include "llvm/ADT/iterator_range.h"
20#include "llvm/Object/Binary.h"
21#include "llvm/Support/Chrono.h"
22#include "llvm/Support/Error.h"
23#include "llvm/Support/FileSystem.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include <algorithm>
26#include <cassert>
27#include <cstdint>
28#include <memory>
29#include <string>
30#include <vector>
31
32namespace llvm {
33namespace object {
34
35class Archive;
36
37class ArchiveMemberHeader {
38public:
39 friend class Archive;
40
41 ArchiveMemberHeader(Archive const *Parent, const char *RawHeaderPtr,
42 uint64_t Size, Error *Err);
43 // ArchiveMemberHeader() = default;
44
45 /// Get the name without looking up long names.
46 Expected<StringRef> getRawName() const;
47
48 /// Get the name looking up long names.
49 Expected<StringRef> getName(uint64_t Size) const;
50
51 /// Members are not larger than 4GB.
52 Expected<uint32_t> getSize() const;
53
54 Expected<sys::fs::perms> getAccessMode() const;
55 Expected<sys::TimePoint<std::chrono::seconds>> getLastModified() const;
56
57 StringRef getRawLastModified() const {
58 return StringRef(ArMemHdr->LastModified,
59 sizeof(ArMemHdr->LastModified)).rtrim(' ');
60 }
61
62 Expected<unsigned> getUID() const;
63 Expected<unsigned> getGID() const;
64
65 // This returns the size of the private struct ArMemHdrType
66 uint64_t getSizeOf() const {
67 return sizeof(ArMemHdrType);
68 }
69
70private:
71 struct ArMemHdrType {
72 char Name[16];
73 char LastModified[12];
74 char UID[6];
75 char GID[6];
76 char AccessMode[8];
77 char Size[10]; ///< Size of data, not including header or padding.
78 char Terminator[2];
79 };
80 Archive const *Parent;
81 ArMemHdrType const *ArMemHdr;
82};
83
84class Archive : public Binary {
85 virtual void anchor();
86
87public:
88 class Child {
89 friend Archive;
90 friend ArchiveMemberHeader;
91
92 const Archive *Parent;
93 ArchiveMemberHeader Header;
94 /// Includes header but not padding byte.
95 StringRef Data;
96 /// Offset from Data to the start of the file.
97 uint16_t StartOfFile;
98
99 Expected<bool> isThinMember() const;
100
101 public:
102 Child(const Archive *Parent, const char *Start, Error *Err);
103 Child(const Archive *Parent, StringRef Data, uint16_t StartOfFile);
104
105 bool operator ==(const Child &other) const {
106 assert(!Parent || !other.Parent || Parent == other.Parent);
107 return Data.begin() == other.Data.begin();
108 }
109
110 const Archive *getParent() const { return Parent; }
111 Expected<Child> getNext() const;
112
113 Expected<StringRef> getName() const;
114 Expected<std::string> getFullName() const;
115 Expected<StringRef> getRawName() const { return Header.getRawName(); }
116
117 Expected<sys::TimePoint<std::chrono::seconds>> getLastModified() const {
118 return Header.getLastModified();
119 }
120
121 StringRef getRawLastModified() const {
122 return Header.getRawLastModified();
123 }
124
125 Expected<unsigned> getUID() const { return Header.getUID(); }
126 Expected<unsigned> getGID() const { return Header.getGID(); }
127
128 Expected<sys::fs::perms> getAccessMode() const {
129 return Header.getAccessMode();
130 }
131
132 /// \return the size of the archive member without the header or padding.
133 Expected<uint64_t> getSize() const;
134 /// \return the size in the archive header for this member.
135 Expected<uint64_t> getRawSize() const;
136
137 Expected<StringRef> getBuffer() const;
138 uint64_t getChildOffset() const;
139
140 Expected<MemoryBufferRef> getMemoryBufferRef() const;
141
142 Expected<std::unique_ptr<Binary>>
143 getAsBinary(LLVMContext *Context = nullptr) const;
144 };
145
146 class child_iterator {
147 Child C;
148 Error *E = nullptr;
149
150 public:
151 child_iterator() : C(Child(nullptr, nullptr, nullptr)) {}
152 child_iterator(const Child &C, Error *E) : C(C), E(E) {}
153
154 const Child *operator->() const { return &C; }
155 const Child &operator*() const { return C; }
156
157 bool operator==(const child_iterator &other) const {
158 // Ignore errors here: If an error occurred during increment then getNext
159 // will have been set to child_end(), and the following comparison should
160 // do the right thing.
161 return C == other.C;
162 }
163
164 bool operator!=(const child_iterator &other) const {
165 return !(*this == other);
166 }
167
168 // Code in loops with child_iterators must check for errors on each loop
169 // iteration. And if there is an error break out of the loop.
170 child_iterator &operator++() { // Preincrement
171 assert(E && "Can't increment iterator with no Error attached");
172 ErrorAsOutParameter ErrAsOutParam(E);
173 if (auto ChildOrErr = C.getNext())
174 C = *ChildOrErr;
175 else {
176 C = C.getParent()->child_end().C;
177 *E = ChildOrErr.takeError();
178 E = nullptr;
179 }
180 return *this;
181 }
182 };
183
184 class Symbol {
185 const Archive *Parent;
186 uint32_t SymbolIndex;
187 uint32_t StringIndex; // Extra index to the string.
188
189 public:
190 Symbol(const Archive *p, uint32_t symi, uint32_t stri)
191 : Parent(p)
192 , SymbolIndex(symi)
193 , StringIndex(stri) {}
194
195 bool operator ==(const Symbol &other) const {
196 return (Parent == other.Parent) && (SymbolIndex == other.SymbolIndex);
197 }
198
199 StringRef getName() const;
200 Expected<Child> getMember() const;
201 Symbol getNext() const;
202 };
203
204 class symbol_iterator {
205 Symbol symbol;
206
207 public:
208 symbol_iterator(const Symbol &s) : symbol(s) {}
209
210 const Symbol *operator->() const { return &symbol; }
211 const Symbol &operator*() const { return symbol; }
212
213 bool operator==(const symbol_iterator &other) const {
214 return symbol == other.symbol;
215 }
216
217 bool operator!=(const symbol_iterator &other) const {
218 return !(*this == other);
219 }
220
221 symbol_iterator& operator++() { // Preincrement
222 symbol = symbol.getNext();
223 return *this;
224 }
225 };
226
227 Archive(MemoryBufferRef Source, Error &Err);
228 static Expected<std::unique_ptr<Archive>> create(MemoryBufferRef Source);
229
230 enum Kind {
231 K_GNU,
232 K_GNU64,
233 K_BSD,
234 K_DARWIN,
235 K_DARWIN64,
236 K_COFF
237 };
238
239 Kind kind() const { return (Kind)Format; }
240 bool isThin() const { return IsThin; }
241
242 child_iterator child_begin(Error &Err, bool SkipInternal = true) const;
243 child_iterator child_end() const;
244 iterator_range<child_iterator> children(Error &Err,
245 bool SkipInternal = true) const {
246 return make_range(child_begin(Err, SkipInternal), child_end());
247 }
248
249 symbol_iterator symbol_begin() const;
250 symbol_iterator symbol_end() const;
251 iterator_range<symbol_iterator> symbols() const {
252 return make_range(symbol_begin(), symbol_end());
253 }
254
255 // Cast methods.
256 static bool classof(Binary const *v) {
257 return v->isArchive();
258 }
259
260 // check if a symbol is in the archive
261 Expected<Optional<Child>> findSym(StringRef name) const;
262
263 bool isEmpty() const;
264 bool hasSymbolTable() const;
265 StringRef getSymbolTable() const { return SymbolTable; }
266 StringRef getStringTable() const { return StringTable; }
267 uint32_t getNumberOfSymbols() const;
268
269 std::vector<std::unique_ptr<MemoryBuffer>> takeThinBuffers() {
270 return std::move(ThinBuffers);
271 }
272
273private:
274 StringRef SymbolTable;
275 StringRef StringTable;
276
277 StringRef FirstRegularData;
278 uint16_t FirstRegularStartOfFile = -1;
279 void setFirstRegular(const Child &C);
280
281 unsigned Format : 3;
282 unsigned IsThin : 1;
283 mutable std::vector<std::unique_ptr<MemoryBuffer>> ThinBuffers;
284};
285
286} // end namespace object
287} // end namespace llvm
288
289#endif // LLVM_OBJECT_ARCHIVE_H
290