aboutsummaryrefslogtreecommitdiffstats
path: root/lib/Archive/Archive.cpp
blob: 1eab27d3eba3a59d36e527f27ce6d361992bcf8c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
//===-- Archive.cpp - Generic LLVM archive functions ------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the implementation of the Archive and ArchiveMember
// classes that is common to both reading and writing archives..
//
//===----------------------------------------------------------------------===//

#include "ArchiveInternals.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/Module.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/system_error.h"
#include <memory>
#include <cstring>
using namespace llvm;

// getMemberSize - compute the actual physical size of the file member as seen
// on disk. This isn't the size of member's payload. Use getSize() for that.
unsigned
ArchiveMember::getMemberSize() const {
  // Basically its the file size plus the header size
  unsigned result =  info.fileSize + sizeof(ArchiveMemberHeader);

  // If it has a long filename, include the name length
  if (hasLongFilename())
    result += path.str().length() + 1;

  // If its now odd lengthed, include the padding byte
  if (result % 2 != 0 )
    result++;

  return result;
}

// This default constructor is only use by the ilist when it creates its
// sentry node. We give it specific static values to make it stand out a bit.
ArchiveMember::ArchiveMember()
  : parent(0), path("--invalid--"), flags(0), data(0)
{
  info.user = sys::Process::GetCurrentUserId();
  info.group = sys::Process::GetCurrentGroupId();
  info.mode = 0777;
  info.fileSize = 0;
  info.modTime = sys::TimeValue::now();
}

// This is the constructor that the Archive class uses when it is building or
// reading an archive. It just defaults a few things and ensures the parent is
// set for the iplist. The Archive class fills in the ArchiveMember's data.
// This is required because correctly setting the data may depend on other
// things in the Archive.
ArchiveMember::ArchiveMember(Archive* PAR)
  : parent(PAR), path(), flags(0), data(0)
{
}

// This method allows an ArchiveMember to be replaced with the data for a
// different file, presumably as an update to the member. It also makes sure
// the flags are reset correctly.
bool ArchiveMember::replaceWith(const sys::Path& newFile, std::string* ErrMsg) {
  bool Exists;
  if (sys::fs::exists(newFile.str(), Exists) || !Exists) {
    if (ErrMsg)
      *ErrMsg = "Can not replace an archive member with a non-existent file";
    return true;
  }

  data = 0;
  path = newFile;

  // SVR4 symbol tables have an empty name
  if (path.str() == ARFILE_SVR4_SYMTAB_NAME)
    flags |= SVR4SymbolTableFlag;
  else
    flags &= ~SVR4SymbolTableFlag;

  // BSD4.4 symbol tables have a special name
  if (path.str() == ARFILE_BSD4_SYMTAB_NAME)
    flags |= BSD4SymbolTableFlag;
  else
    flags &= ~BSD4SymbolTableFlag;

  // LLVM symbol tables have a very specific name
  if (path.str() == ARFILE_LLVM_SYMTAB_NAME)
    flags |= LLVMSymbolTableFlag;
  else
    flags &= ~LLVMSymbolTableFlag;

  // String table name
  if (path.str() == ARFILE_STRTAB_NAME)
    flags |= StringTableFlag;
  else
    flags &= ~StringTableFlag;

  // If it has a slash then it has a path
  bool hasSlash = path.str().find('/') != std::string::npos;
  if (hasSlash)
    flags |= HasPathFlag;
  else
    flags &= ~HasPathFlag;

  // If it has a slash or its over 15 chars then its a long filename format
  if (hasSlash || path.str().length() > 15)
    flags |= HasLongFilenameFlag;
  else
    flags &= ~HasLongFilenameFlag;

  // Get the signature and status info
  const char* signature = (const char*) data;
  SmallString<4> magic;
  if (!signature) {
    sys::fs::get_magic(path.str(), magic.capacity(), magic);
    signature = magic.c_str();
    const sys::FileStatus *FSinfo = path.getFileStatus(false, ErrMsg);
    if (FSinfo)
      info = *FSinfo;
    else
      return true;
  }

  // Determine what kind of file it is.
  switch (sys::IdentifyFileType(signature,4)) {
    case sys::Bitcode_FileType:
      flags |= BitcodeFlag;
      break;
    default:
      flags &= ~BitcodeFlag;
      break;
  }
  return false;
}

// Archive constructor - this is the only constructor that gets used for the
// Archive class. Everything else (default,copy) is deprecated. This just
// initializes and maps the file into memory, if requested.
Archive::Archive(const sys::Path& filename, LLVMContext& C)
  : archPath(filename), members(), mapfile(0), base(0), symTab(), strtab(),
    symTabSize(0), firstFileOffset(0), modules(), foreignST(0), Context(C) {
}

bool
Archive::mapToMemory(std::string* ErrMsg) {
  OwningPtr<MemoryBuffer> File;
  if (error_code ec = MemoryBuffer::getFile(archPath.c_str(), File)) {
    if (ErrMsg)
      *ErrMsg = ec.message();
    return true;
  }
  mapfile = File.take();
  base = mapfile->getBufferStart();
  return false;
}

void Archive::cleanUpMemory() {
  // Shutdown the file mapping
  delete mapfile;
  mapfile = 0;
  base = 0;

  // Forget the entire symbol table
  symTab.clear();
  symTabSize = 0;

  firstFileOffset = 0;

  // Free the foreign symbol table member
  if (foreignST) {
    delete foreignST;
    foreignST = 0;
  }

  // Delete any Modules and ArchiveMember's we've allocated as a result of
  // symbol table searches.
  for (ModuleMap::iterator I=modules.begin(), E=modules.end(); I != E; ++I ) {
    delete I->second.first;
    delete I->second.second;
  }
}

// Archive destructor - just clean up memory
Archive::~Archive() {
  cleanUpMemory();
}



static void getSymbols(Module*M, std::vector<std::string>& symbols) {
  // Loop over global variables
  for (Module::global_iterator GI = M->global_begin(), GE=M->global_end(); GI != GE; ++GI)
    if (!GI->isDeclaration() && !GI->hasLocalLinkage())
      if (!GI->getName().empty())
        symbols.push_back(GI->getName());

  // Loop over functions
  for (Module::iterator FI = M->begin(), FE = M->end(); FI != FE; ++FI)
    if (!FI->isDeclaration() && !FI->hasLocalLinkage())
      if (!FI->getName().empty())
        symbols.push_back(FI->getName());

  // Loop over aliases
  for (Module::alias_iterator AI = M->alias_begin(), AE = M->alias_end();
       AI != AE; ++AI) {
    if (AI->hasName())
      symbols.push_back(AI->getName());
  }
}

// Get just the externally visible defined symbols from the bitcode
bool llvm::GetBitcodeSymbols(const sys::Path& fName,
                             LLVMContext& Context,
                             std::vector<std::string>& symbols,
                             std::string* ErrMsg) {
  OwningPtr<MemoryBuffer> Buffer;
  if (error_code ec = MemoryBuffer::getFileOrSTDIN(fName.c_str(), Buffer)) {
    if (ErrMsg) *ErrMsg = "Could not open file '" + fName.str() + "'" + ": "
                        + ec.message();
    return true;
  }

  Module *M = ParseBitcodeFile(Buffer.get(), Context, ErrMsg);
  if (!M)
    return true;

  // Get the symbols
  getSymbols(M, symbols);

  // Done with the module.
  delete M;
  return true;
}

Module*
llvm::GetBitcodeSymbols(const char *BufPtr, unsigned Length,
                        const std::string& ModuleID,
                        LLVMContext& Context,
                        std::vector<std::string>& symbols,
                        std::string* ErrMsg) {
  // Get the module.
  OwningPtr<MemoryBuffer> Buffer(
    MemoryBuffer::getMemBufferCopy(StringRef(BufPtr, Length),ModuleID.c_str()));

  Module *M = ParseBitcodeFile(Buffer.get(), Context, ErrMsg);
  if (!M)
    return 0;

  // Get the symbols
  getSymbols(M, symbols);

  // Done with the module. Note that it's the caller's responsibility to delete
  // the Module.
  return M;
}