//===- Multilib.cpp - Multilib Implementation -----------------------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#include "clang/Driver/Multilib.h"

#include "clang/Basic/LLVM.h"

#include "llvm/ADT/SmallString.h"

#include "llvm/ADT/StringMap.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/ADT/StringSet.h"

#include "llvm/Support/Compiler.h"

#include "llvm/Support/ErrorHandling.h"

#include "llvm/Support/Path.h"

#include "llvm/Support/Regex.h"

#include "llvm/Support/raw_ostream.h"

#include <algorithm>

#include <cassert>

#include <string>

using namespace clang;

using namespace driver;

using namespace llvm::sys;

/// normalize Segment to "/foo/bar" or "".

static void normalizePathSegment(std::string &Segment) {

  StringRef seg = Segment;

  // Prune trailing "/" or "./"

  while (true) {

    StringRef last = path::filename(seg);

    if (last != ".")

      break;

    seg = path::parent_path(seg);

  }

  if (seg.empty() || 
seg == "/"174k
) {

    Segment.clear();

    return;

  }

  // Add leading '/'

  if (seg.front() != '/') {

    Segment = "/" + seg.str();

  } else {

    Segment = std::string(seg);

  }

}

Multilib::Multilib(StringRef GCCSuffix, StringRef OSSuffix,

                   StringRef IncludeSuffix, int Priority)

    : GCCSuffix(GCCSuffix), OSSuffix(OSSuffix), IncludeSuffix(IncludeSuffix),

      Priority(Priority) {

  normalizePathSegment(this->GCCSuffix);

  normalizePathSegment(this->OSSuffix);

  normalizePathSegment(this->IncludeSuffix);

}

Multilib &Multilib::gccSuffix(StringRef S) {

  GCCSuffix = std::string(S);

  normalizePathSegment(GCCSuffix);

  return *this;

}

Multilib &Multilib::osSuffix(StringRef S) {

  OSSuffix = std::string(S);

  normalizePathSegment(OSSuffix);

  return *this;

}

Multilib &Multilib::includeSuffix(StringRef S) {

  IncludeSuffix = std::string(S);

  normalizePathSegment(IncludeSuffix);

  return *this;

}

LLVM_DUMP_METHOD void Multilib::dump() const {

  print(llvm::errs());

}

void Multilib::print(raw_ostream &OS) const {

  assert(GCCSuffix.empty() || (StringRef(GCCSuffix).front() == '/'));

  if (GCCSuffix.empty())

    OS << ".";

  else {

    OS << StringRef(GCCSuffix).drop_front();

  }

  OS << ";";

  for (StringRef Flag : Flags) {

    if (Flag.front() == '+')

      OS << "@" << Flag.substr(1);

  }

}

bool Multilib::isValid() const {

  llvm::StringMap<int> FlagSet;

  for (unsigned I = 0, N = Flags.size(); I != N; 
++I469k
) {

    StringRef Flag(Flags[I]);

    llvm::StringMap<int>::iterator SI = FlagSet.find(Flag.substr(1));

    assert(StringRef(Flag).front() == '+' || StringRef(Flag).front() == '-');

    if (SI == FlagSet.end())

      FlagSet[Flag.substr(1)] = I;

    else if (Flags[I] != Flags[SI->getValue()])

      return false;

  }

  return true;

}

bool Multilib::operator==(const Multilib &Other) const {

  // Check whether the flags sets match

  // allowing for the match to be order invariant

  llvm::StringSet<> MyFlags;

  for (const auto &Flag : Flags)

    MyFlags.insert(Flag);

  for (const auto &Flag : Other.Flags)

    if (MyFlags.find(Flag) == MyFlags.end())

      return false;

  if (osSuffix() != Other.osSuffix())

    return false;

  if (gccSuffix() != Other.gccSuffix())

    return false;

  if (includeSuffix() != Other.includeSuffix())

    return false;

  return true;

}

raw_ostream &clang::driver::operator<<(raw_ostream &OS, const Multilib &M) {

  M.print(OS);

  return OS;

}

MultilibSet &MultilibSet::Maybe(const Multilib &M) {

  Multilib Opposite;

  // Negate any '+' flags

  for (StringRef Flag : M.flags()) {

    if (Flag.front() == '+')

      Opposite.flags().push_back(("-" + Flag.substr(1)).str());

  }

  return Either(M, Opposite);

}

MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2) {

  return Either({M1, M2});

}

MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2,

                                 const Multilib &M3) {

  return Either({M1, M2, M3});

}

MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2,

                                 const Multilib &M3, const Multilib &M4) {

  return Either({M1, M2, M3, M4});

}

MultilibSet &MultilibSet::Either(const Multilib &M1, const Multilib &M2,

                                 const Multilib &M3, const Multilib &M4,

                                 const Multilib &M5) {

  return Either({M1, M2, M3, M4, M5});

}

static Multilib compose(const Multilib &Base, const Multilib &New) {

  SmallString<128> GCCSuffix;

  llvm::sys::path::append(GCCSuffix, "/", Base.gccSuffix(), New.gccSuffix());

  SmallString<128> OSSuffix;

  llvm::sys::path::append(OSSuffix, "/", Base.osSuffix(), New.osSuffix());

  SmallString<128> IncludeSuffix;

  llvm::sys::path::append(IncludeSuffix, "/", Base.includeSuffix(),

                          New.includeSuffix());

  Multilib Composed(GCCSuffix, OSSuffix, IncludeSuffix);

  Multilib::flags_list &Flags = Composed.flags();

  Flags.insert(Flags.end(), Base.flags().begin(), Base.flags().end());

  Flags.insert(Flags.end(), New.flags().begin(), New.flags().end());

  return Composed;

}

MultilibSet &MultilibSet::Either(ArrayRef<Multilib> MultilibSegments) {

  multilib_list Composed;

  if (Multilibs.empty())

    Multilibs.insert(Multilibs.end(), MultilibSegments.begin(),

                     MultilibSegments.end());

  else {

    for (const auto &New : MultilibSegments) {

      for (const auto &Base : *this) {

        Multilib MO = compose(Base, New);

        if (MO.isValid())

          Composed.push_back(MO);

      }

    }

    Multilibs = Composed;

  }

  return *this;

}

MultilibSet &MultilibSet::FilterOut(FilterCallback F) {

  filterInPlace(F, Multilibs);

  return *this;

}

MultilibSet &MultilibSet::FilterOut(const char *Regex) {

  llvm::Regex R(Regex);

#ifndef NDEBUG

  std::string Error;

  if (!R.isValid(Error)) {

    llvm::errs() << Error;

    llvm_unreachable("Invalid regex!");

  }

#endif

  
filterInPlace([&R](const Multilib &M) 1.12k
{ return R.match(M.gccSuffix()); },

                Multilibs);

  return *this;

}

void MultilibSet::push_back(const Multilib &M) { Multilibs.push_back(M); }

void MultilibSet::combineWith(const MultilibSet &Other) {

  Multilibs.insert(Multilibs.end(), Other.begin(), Other.end());

}

static bool isFlagEnabled(StringRef Flag) {

  char Indicator = Flag.front();

  assert(Indicator == '+' || Indicator == '-');

  return Indicator == '+';

}

bool MultilibSet::select(const Multilib::flags_list &Flags, Multilib &M) const {

  llvm::StringMap<bool> FlagSet;

  // Stuff all of the flags into the FlagSet such that a true mappend indicates

  // the flag was enabled, and a false mappend indicates the flag was disabled.

  for (StringRef Flag : Flags)

    FlagSet[Flag.substr(1)] = isFlagEnabled(Flag);

  multilib_list Filtered = filterCopy([&FlagSet](const Multilib &M) {

    for (StringRef Flag : M.flags()) {

      llvm::StringMap<bool>::const_iterator SI = FlagSet.find(Flag.substr(1));

      if (SI != FlagSet.end())

        if (SI->getValue() != isFlagEnabled(Flag))

          return true;

    }

    return false;

  }, Multilibs);

  if (Filtered.empty())

    return false;

  if (Filtered.size() == 1) {

    M = Filtered[0];

    return true;

  }

  // Sort multilibs by priority and select the one with the highest priority.

  llvm::sort(Filtered.begin(), Filtered.end(),

             [](const Multilib &a, const Multilib &b) -> bool {

               return a.priority() > b.priority();

             });

  if (Filtered[0].priority() > Filtered[1].priority()) {

    M = Filtered[0];

    return true;

  }

  // TODO: We should consider returning llvm::Error rather than aborting.

  assert(false && "More than one multilib with the same priority");

  return false;

}

LLVM_DUMP_METHOD void MultilibSet::dump() const {

  print(llvm::errs());

}

void MultilibSet::print(raw_ostream &OS) const {

  for (const auto &M : *this)

    OS << M << "\n";

}

MultilibSet::multilib_list MultilibSet::filterCopy(FilterCallback F,

                                                   const multilib_list &Ms) {

  multilib_list Copy(Ms);

  filterInPlace(F, Copy);

  return Copy;

}

void MultilibSet::filterInPlace(FilterCallback F, multilib_list &Ms) {

  Ms.erase(std::remove_if(Ms.begin(), Ms.end(), F), Ms.end());

}

raw_ostream &clang::driver::operator<<(raw_ostream &OS, const MultilibSet &MS) {

  MS.print(OS);

  return OS;

}