//===- lib/ReaderWriter/PECOFF/PECOFFLinkingContext.cpp -------------------===//
//
//                             The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "Atoms.h"
#include "GroupedSectionsPass.h"
#include "IdataPass.h"
#include "LinkerGeneratedSymbolFile.h"

#include "llvm/ADT/SmallString.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Path.h"
#include "lld/Core/InputFiles.h"
#include "lld/Core/PassManager.h"
#include "lld/Passes/LayoutPass.h"
#include "lld/ReaderWriter/PECOFFLinkingContext.h"
#include "lld/ReaderWriter/Reader.h"
#include "lld/ReaderWriter/Simple.h"
#include "lld/ReaderWriter/Writer.h"

namespace lld {

namespace {
bool containDirectoryName(StringRef path) {
  SmallString<128> smallStr = StringRef(path);
  llvm::sys::path::remove_filename(smallStr);
  return !smallStr.str().empty();
}
} // anonymous namespace

error_code PECOFFLinkingContext::parseFile(
    std::unique_ptr<MemoryBuffer> &mb,
    std::vector<std::unique_ptr<File>> &result) const {
  return _reader->parseFile(mb, result);
}

bool PECOFFLinkingContext::validateImpl(raw_ostream &diagnostics) {
  if (_inputFiles.empty()) {
    diagnostics << "No input files\n";
    return true;
  }

  if (_stackReserve < _stackCommit) {
    diagnostics << "Invalid stack size: reserve size must be equal to or "
                << "greater than commit size, but got " << _stackCommit
                << " and " << _stackReserve << ".\n";
    return true;
  }

  if (_heapReserve < _heapCommit) {
    diagnostics << "Invalid heap size: reserve size must be equal to or "
                << "greater than commit size, but got " << _heapCommit
                << " and " << _heapReserve << ".\n";
    return true;
  }

  _reader = createReaderPECOFF(*this);
  _writer = createWriterPECOFF(*this);
  return false;
}

void PECOFFLinkingContext::addImplicitFiles(InputFiles &files) const {
  // Add a pseudo file for "/include" linker option.
  auto *undefFile = new (_alloc) coff::UndefinedSymbolFile(*this);
  files.prependFile(*undefFile);

  auto *linkerFile = new (_alloc) coff::LinkerGeneratedSymbolFile(*this);
  files.appendFile(*linkerFile);
}

/// Append the given file to the input file list. The file must be an object
/// file or an import library file.
void PECOFFLinkingContext::appendInputFileOrLibrary(std::string path) {
  StringRef ext = llvm::sys::path::extension(path);
  // This is an import library file. Look for the library file in the search
  // paths, unless the path contains a directory name.
  if (ext.equals_lower(".lib")) {
    if (containDirectoryName(path)) {
      appendInputFile(path);
      return;
    }
    appendLibraryFile(path);
    return;
  }
  // This is an object file otherwise. Add ".obj" extension if the given path
  // name has no file extension.
  if (ext.empty())
    path.append(".obj");
  appendInputFile(allocateString(path));
}

/// Try to find the input library file from the search paths and append it to
/// the input file list. Returns true if the library file is found.
void PECOFFLinkingContext::appendLibraryFile(StringRef filename) {
  // Current directory always takes precedence over the search paths.
  if (llvm::sys::fs::exists(filename)) {
    appendInputFile(filename);
    return;
  }
  // Iterate over the search paths.
  for (StringRef dir : _inputSearchPaths) {
    SmallString<128> path = dir;
    llvm::sys::path::append(path, filename);
    if (llvm::sys::fs::exists(path.str())) {
      appendInputFile(allocateString(path.str()));
      return;
    }
  }
  appendInputFile(filename);
}

Writer &PECOFFLinkingContext::writer() const { return *_writer; }

ErrorOr<Reference::Kind>
PECOFFLinkingContext::relocKindFromString(StringRef str) const {
  return make_error_code(yaml_reader_error::illegal_value);
}

ErrorOr<std::string>
PECOFFLinkingContext::stringFromRelocKind(Reference::Kind kind) const {
  return make_error_code(yaml_reader_error::illegal_value);
}

void PECOFFLinkingContext::addPasses(PassManager &pm) const {
  pm.add(std::unique_ptr<Pass>(new pecoff::GroupedSectionsPass()));
  pm.add(std::unique_ptr<Pass>(new pecoff::IdataPass()));
  pm.add(std::unique_ptr<Pass>(new LayoutPass()));
}

} // end namespace lld