//===- llvm/Support/Unix/Host.inc -------------------------------*- C++ -*-===//

//

// 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

//

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

//

// This file implements the UNIX Host support.

//

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

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

//=== WARNING: Implementation here must contain only generic UNIX code that

//===          is guaranteed to work on *all* UNIX variants.

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

#include "Unix.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/Config/config.h"

#include <cctype>

#include <string>

#include <sys/utsname.h>

using namespace llvm;

static std::string getOSVersion() {

  struct utsname info;

  if (uname(&info))

    return "";

  return info.release;

}

static std::string updateTripleOSVersion(std::string TargetTripleString) {

  // On darwin, we want to update the version to match that of the target.

  std::string::size_type DarwinDashIdx = TargetTripleString.find("-darwin");

  if (DarwinDashIdx != std::string::npos) {

    TargetTripleString.resize(DarwinDashIdx + strlen("-darwin"));

    TargetTripleString += getOSVersion();

    return TargetTripleString;

  }

  std::string::size_type MacOSDashIdx = TargetTripleString.find("-macos");

  if (MacOSDashIdx != std::string::npos) {

    TargetTripleString.resize(MacOSDashIdx);

    // Reset the OS to darwin as the OS version from `uname` doesn't use the

    // macOS version scheme.

    TargetTripleString += "-darwin";

    TargetTripleString += getOSVersion();

  }

  // On AIX, the AIX version and release should be that of the current host

  // unless if the version has already been specified.

  if (Triple(LLVM_HOST_TRIPLE).getOS() == Triple::AIX) {

    Triple TT(TargetTripleString);

    if (TT.getOS() == Triple::AIX && !TT.getOSMajorVersion()) {

      struct utsname name;

      if (uname(&name) != -1) {

        std::string NewOSName = std::string(Triple::getOSTypeName(Triple::AIX));

        NewOSName += name.version;

        NewOSName += '.';

        NewOSName += name.release;

        NewOSName += ".0.0";

        TT.setOSName(NewOSName);

        return TT.str();

      }

    }

  }

  return TargetTripleString;

}

std::string sys::getDefaultTargetTriple() {

  std::string TargetTripleString =

      updateTripleOSVersion(LLVM_DEFAULT_TARGET_TRIPLE);

  // Override the default target with an environment variable named by

  // LLVM_TARGET_TRIPLE_ENV.

#if defined(LLVM_TARGET_TRIPLE_ENV)

  if (const char *EnvTriple = std::getenv(LLVM_TARGET_TRIPLE_ENV))

    TargetTripleString = EnvTriple;

#endif

  return TargetTripleString;

}