llvm/lib/ObjCopy/XCOFF/XCOFFReader.cpp

   1 //===- XCOFFReader.cpp ----------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "XCOFFReader.h"
  10
  11 namespace llvm {
  12 namespace objcopy {
  13 namespace xcoff {
  14
  15 using namespace object;
  16
  17 Error XCOFFReader::readSections(Object &Obj) const {
  18   ArrayRef<XCOFFSectionHeader32> Sections = XCOFFObj.sections32();
  19   for (const XCOFFSectionHeader32 &Sec : Sections) {
  20     Section ReadSec;
  21     // Section header.
  22     ReadSec.SectionHeader = Sec;
  23     DataRefImpl SectionDRI;
  24     SectionDRI.p = reinterpret_cast<uintptr_t>(&Sec);
  25
  26     // Section data.
  27     if (Sec.SectionSize) {
  28       Expected<ArrayRef<uint8_t>> ContentsRef =
  29           XCOFFObj.getSectionContents(SectionDRI);
  30       if (!ContentsRef)
  31         return ContentsRef.takeError();
  32       ReadSec.Contents = ContentsRef.get();
  33     }
  34
  35     // Relocations.
  36     if (Sec.NumberOfRelocations) {
  37       auto Relocations =
  38           XCOFFObj.relocations<XCOFFSectionHeader32, XCOFFRelocation32>(Sec);
  39       if (!Relocations)
  40         return Relocations.takeError();
  41       for (const XCOFFRelocation32 &Rel : Relocations.get())
  42         ReadSec.Relocations.push_back(Rel);
  43     }
  44
  45     Obj.Sections.push_back(std::move(ReadSec));
  46   }
  47   return Error::success();
  48 }
  49
  50 Error XCOFFReader::readSymbols(Object &Obj) const {
  51   std::vector<Symbol> Symbols;
  52   Symbols.reserve(XCOFFObj.getNumberOfSymbolTableEntries());
  53   for (SymbolRef Sym : XCOFFObj.symbols()) {
  54     Symbol ReadSym;
  55     DataRefImpl SymbolDRI = Sym.getRawDataRefImpl();
  56     XCOFFSymbolRef SymbolEntRef = XCOFFObj.toSymbolRef(SymbolDRI);
  57     ReadSym.Sym = *SymbolEntRef.getSymbol32();
  58     // Auxiliary entries.
  59     if (SymbolEntRef.getNumberOfAuxEntries()) {
  60       const char *Start = reinterpret_cast<const char *>(
  61           SymbolDRI.p + XCOFF::SymbolTableEntrySize);
  62       Expected<StringRef> RawAuxEntriesOrError = XCOFFObj.getRawData(
  63           Start,
  64           XCOFF::SymbolTableEntrySize * SymbolEntRef.getNumberOfAuxEntries(),
  65           StringRef("symbol"));
  66       if (!RawAuxEntriesOrError)
  67         return RawAuxEntriesOrError.takeError();
  68       ReadSym.AuxSymbolEntries = RawAuxEntriesOrError.get();
  69     }
  70     Obj.Symbols.push_back(std::move(ReadSym));
  71   }
  72   return Error::success();
  73 }
  74
  75 Expected<std::unique_ptr<Object>> XCOFFReader::create() const {
  76   auto Obj = std::make_unique<Object>();
  77   // Only 32-bit supported now.
  78   if (XCOFFObj.is64Bit())
  79     return createStringError(object_error::invalid_file_type,
  80                              "64-bit XCOFF is not supported yet");
  81   // Read the file header.
  82   Obj->FileHeader = *XCOFFObj.fileHeader32();
  83   // Read the optional header.
  84   if (XCOFFObj.getOptionalHeaderSize())
  85     Obj->OptionalFileHeader = *XCOFFObj.auxiliaryHeader32();
  86   // Read each section.
  87   Obj->Sections.reserve(XCOFFObj.getNumberOfSections());
  88   if (Error E = readSections(*Obj))
  89     return std::move(E);
  90   // Read each symbol.
  91   Obj->Symbols.reserve(XCOFFObj.getRawNumberOfSymbolTableEntries32());
  92   if (Error E = readSymbols(*Obj))
  93     return std::move(E);
  94   // String table.
  95   Obj->StringTable = XCOFFObj.getStringTable();
  96   return std::move(Obj);
  97 }
  98
  99 } // end namespace xcoff
 100 } // end namespace objcopy
 101 } // end namespace llvm