Archive.cpp revision 6b8a63ae583b53a942dca7c681f4cf161c90d35e 
1//===-- Archive.cpp - Generic LLVM archive functions ------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Reid Spencer and is distributed under the
6// University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains the implementation of the Archive and ArchiveMember
11// classes that is common to both reading and writing archives..
12//
13//===----------------------------------------------------------------------===//
14
15#include "ArchiveInternals.h"
16#include "llvm/ModuleProvider.h"
17#include "llvm/System/Process.h"
18
19using namespace llvm;
20
21// getMemberSize - compute the actual physical size of the file member as seen
22// on disk. This isn't the size of member's payload. Use getSize() for that.
23unsigned
24ArchiveMember::getMemberSize() const {
25  // Basically its the file size plus the header size
26  unsigned result =  info.fileSize + sizeof(ArchiveMemberHeader);
27
28  // If it has a long filename, include the name length
29  if (hasLongFilename())
30    result += path.toString().length() + 1;
31
32  // If its now odd lengthed, include the padding byte
33  if (result % 2 != 0 )
34    result++;
35
36  return result;
37}
38
39// This default constructor is only use by the ilist when it creates its
40// sentry node. We give it specific static values to make it stand out a bit.
41ArchiveMember::ArchiveMember()
42  : next(0), prev(0), parent(0), path("<invalid>"), flags(0), data(0)
43{
44  info.user = sys::Process::GetCurrentUserId();
45  info.group = sys::Process::GetCurrentGroupId();
46  info.mode = 0777;
47  info.fileSize = 0;
48  info.modTime = sys::TimeValue::now();
49}
50
51// This is the constructor that the Archive class uses when it is building or
52// reading an archive. It just defaults a few things and ensures the parent is
53// set for the iplist. The Archive class fills in the ArchiveMember's data.
54// This is required because correctly setting the data may depend on other
55// things in the Archive.
56ArchiveMember::ArchiveMember(Archive* PAR)
57  : next(0), prev(0), parent(PAR), path(), flags(0), data(0)
58{
59}
60
61// This method allows an ArchiveMember to be replaced with the data for a
62// different file, presumably as an update to the member. It also makes sure
63// the flags are reset correctly.
64void ArchiveMember::replaceWith(const sys::Path& newFile) {
65  assert(newFile.exists() && "Can't replace with a non-existent file");
66  data = 0;
67  path = newFile;
68
69  // SVR4 symbol tables have an empty name
70  if (path.toString() == ARFILE_SVR4_SYMTAB_NAME)
71    flags |= SVR4SymbolTableFlag;
72  else
73    flags &= ~SVR4SymbolTableFlag;
74
75  // BSD4.4 symbol tables have a special name
76  if (path.toString() == ARFILE_BSD4_SYMTAB_NAME)
77    flags |= BSD4SymbolTableFlag;
78  else
79    flags &= ~BSD4SymbolTableFlag;
80
81  // LLVM symbol tables have a very specific name
82  if (path.toString() == ARFILE_LLVM_SYMTAB_NAME)
83    flags |= LLVMSymbolTableFlag;
84  else
85    flags &= ~LLVMSymbolTableFlag;
86
87  // String table name
88  if (path.toString() == ARFILE_STRTAB_NAME)
89    flags |= StringTableFlag;
90  else
91    flags &= ~StringTableFlag;
92
93  // If it has a slash then it has a path
94  bool hasSlash = path.toString().find('/') != std::string::npos;
95  if (hasSlash)
96    flags |= HasPathFlag;
97  else
98    flags &= ~HasPathFlag;
99
100  // If it has a slash or its over 15 chars then its a long filename format
101  if (hasSlash || path.toString().length() > 15)
102    flags |= HasLongFilenameFlag;
103  else
104    flags &= ~HasLongFilenameFlag;
105
106  // Get the signature and status info
107  std::string magic;
108  const char* signature = (const char*) data;
109  if (!signature) {
110    path.getMagicNumber(magic,4);
111    signature = magic.c_str();
112    path.getStatusInfo(info);
113  }
114
115  // Determine what kind of file it is
116  switch (sys::IdentifyFileType(signature,4)) {
117    case sys::BytecodeFileType:
118      flags |= BytecodeFlag;
119      break;
120    case sys::CompressedBytecodeFileType:
121      flags |= CompressedBytecodeFlag;
122      flags &= ~CompressedFlag;
123      break;
124    default:
125      flags &= ~(BytecodeFlag|CompressedBytecodeFlag);
126      break;
127  }
128}
129
130// Archive constructor - this is the only constructor that gets used for the
131// Archive class. Everything else (default,copy) is deprecated. This just
132// initializes and maps the file into memory, if requested.
133Archive::Archive(const sys::Path& filename, bool map )
134  : archPath(filename), members(), mapfile(0), base(0), symTab(), strtab(),
135    symTabSize(0), firstFileOffset(0), modules(), foreignST(0)
136{
137  if (map) {
138    mapfile = new sys::MappedFile(filename);
139    base = (char*) mapfile->map();
140  }
141}
142
143// Archive destructor - just clean up memory
144Archive::~Archive() {
145  // Shutdown the file mapping
146  if (mapfile) {
147    mapfile->close();
148    delete mapfile;
149  }
150  // Delete any ModuleProviders and ArchiveMember's we've allocated as a result
151  // of symbol table searches.
152  for (ModuleMap::iterator I=modules.begin(), E=modules.end(); I != E; ++I ) {
153    delete I->second.first;
154    delete I->second.second;
155  }
156}
157
158