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Archive.cpp

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00001 //===-- Archive.cpp - Generic LLVM archive functions ------------*- C++ -*-===//
00002 // 
00003 //                     The LLVM Compiler Infrastructure
00004 //
00005 // This file was developed by Reid Spencer and is distributed under the 
00006 // University of Illinois Open Source License. See LICENSE.TXT for details.
00007 // 
00008 //===----------------------------------------------------------------------===//
00009 //
00010 // This file contains the implementation of the Archive and ArchiveMember
00011 // classes that is common to both reading and writing archives..
00012 //
00013 //===----------------------------------------------------------------------===//
00014 
00015 #include "ArchiveInternals.h"
00016 #include "llvm/ModuleProvider.h"
00017 
00018 using namespace llvm;
00019 
00020 // getMemberSize - compute the actual physical size of the file member as seen
00021 // on disk. This isn't the size of member's payload. Use getSize() for that.
00022 unsigned
00023 ArchiveMember::getMemberSize() const {
00024   // Basically its the file size plus the header size
00025   unsigned result =  info.fileSize + sizeof(ArchiveMemberHeader);
00026 
00027   // If it has a long filename, include the name length
00028   if (hasLongFilename())
00029     result += path.get().length() + 1;
00030 
00031   // If its now odd lengthed, include the padding byte
00032   if (result % 2 != 0 ) 
00033     result++;
00034 
00035   return result;
00036 }
00037 
00038 // This default constructor is only use by the ilist when it creates its
00039 // sentry node. We give it specific static values to make it stand out a bit.
00040 ArchiveMember::ArchiveMember() 
00041   : next(0), prev(0), parent(0), path("<invalid>"), flags(0), data(0)
00042 {
00043   info.user = 1000;
00044   info.group = 1000; 
00045   info.mode = 0777; 
00046   info.fileSize = 0; 
00047   info.modTime = sys::TimeValue::now();
00048 }
00049 
00050 // This is the constructor that the Archive class uses when it is building or
00051 // reading an archive. It just defaults a few things and ensures the parent is
00052 // set for the iplist. The Archive class fills in the ArchiveMember's data. 
00053 // This is required because correctly setting the data may depend on other 
00054 // things in the Archive.
00055 ArchiveMember::ArchiveMember(Archive* PAR)
00056   : next(0), prev(0), parent(PAR), path(), flags(0), data(0)
00057 {
00058 }
00059 
00060 // This method allows an ArchiveMember to be replaced with the data for a 
00061 // different file, presumably as an update to the member. It also makes sure
00062 // the flags are reset correctly.
00063 void ArchiveMember::replaceWith(const sys::Path& newFile) {
00064   assert(newFile.exists() && "Can't replace with a non-existent file");
00065   data = 0;
00066   path = newFile;
00067 
00068   // SVR4 symbol tables have an empty name
00069   if (path.get() == ARFILE_SVR4_SYMTAB_NAME)
00070     flags |= SVR4SymbolTableFlag;
00071   else
00072     flags &= ~SVR4SymbolTableFlag;
00073 
00074   // BSD4.4 symbol tables have a special name
00075   if (path.get() == ARFILE_BSD4_SYMTAB_NAME)
00076     flags |= BSD4SymbolTableFlag;
00077   else
00078     flags &= ~BSD4SymbolTableFlag;
00079 
00080   // LLVM symbol tables have a very specific name
00081   if (path.get() == ARFILE_LLVM_SYMTAB_NAME)
00082     flags |= LLVMSymbolTableFlag;
00083   else
00084     flags &= ~LLVMSymbolTableFlag;
00085 
00086   // String table name
00087   if (path.get() == ARFILE_STRTAB_NAME)
00088     flags |= StringTableFlag;
00089   else
00090     flags &= ~StringTableFlag;
00091 
00092   // If it has a slash then it has a path
00093   bool hasSlash = path.get().find('/') != std::string::npos;
00094   if (hasSlash)
00095     flags |= HasPathFlag;
00096   else
00097     flags &= ~HasPathFlag;
00098 
00099   // If it has a slash or its over 15 chars then its a long filename format
00100   if (hasSlash || path.get().length() > 15)
00101     flags |= HasLongFilenameFlag;
00102   else
00103     flags &= ~HasLongFilenameFlag;
00104 
00105   // Get the signature and status info
00106   std::string magic;
00107   const char* signature = (const char*) data;
00108   if (!signature) {
00109     path.getMagicNumber(magic,4);
00110     signature = magic.c_str();
00111     path.getStatusInfo(info);
00112   }
00113 
00114   // Determine what kind of file it is
00115   switch (sys::IdentifyFileType(signature,4)) {
00116     case sys::BytecodeFileType:
00117       flags |= BytecodeFlag;
00118       break;
00119     case sys::CompressedBytecodeFileType:
00120       flags |= CompressedBytecodeFlag;
00121       flags &= ~CompressedFlag;
00122       break;
00123     default:
00124       flags &= ~(BytecodeFlag|CompressedBytecodeFlag);
00125       break;
00126   }
00127 }
00128 
00129 // Archive constructor - this is the only constructor that gets used for the
00130 // Archive class. Everything else (default,copy) is deprecated. This just 
00131 // initializes and maps the file into memory, if requested.
00132 Archive::Archive(const sys::Path& filename, bool map ) 
00133   : archPath(filename), members(), mapfile(0), base(0), symTab(), strtab(),
00134     symTabSize(0), firstFileOffset(0), modules(), foreignST(0)
00135 {
00136   if (map) {
00137     mapfile = new sys::MappedFile(filename);
00138     base = (char*) mapfile->map();
00139   }
00140 }
00141 
00142 // Archive destructor - just clean up memory
00143 Archive::~Archive() {
00144   // Shutdown the file mapping
00145   if (mapfile) {
00146     mapfile->unmap();
00147     delete mapfile;
00148   }
00149   // Delete any ModuleProviders and ArchiveMember's we've allocated as a result
00150   // of symbol table searches.
00151   for (ModuleMap::iterator I=modules.begin(), E=modules.end(); I != E; ++I ) {
00152     delete I->second.first;
00153     delete I->second.second;
00154   }
00155 }
00156 
00157 // vim: sw=2 ai