lldb/source/Target/Platform.cpp

//===-- Platform.cpp --------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// C Includes
// C++ Includes
#include <algorithm>
#include <fstream>
#include <vector>

// Other libraries and framework includes
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"

// Project includes
#include "Utility/ModuleCache.h"
#include "lldb/Breakpoint/BreakpointIDList.h"
#include "lldb/Breakpoint/BreakpointLocation.h"
#include "lldb/Core/DataBufferHeap.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/StreamFile.h"
#include "lldb/Core/StructuredData.h"
#include "lldb/Host/FileSpec.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Host/Host.h"
#include "lldb/Host/HostInfo.h"
#include "lldb/Interpreter/OptionValueProperties.h"
#include "lldb/Interpreter/Property.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Target/Platform.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/UnixSignals.h"
#include "lldb/Utility/Error.h"

// Define these constants from POSIX mman.h rather than include the file
// so that they will be correct even when compiled on Linux.
#define MAP_PRIVATE 2
#define MAP_ANON 0x1000

using namespace lldb;
using namespace lldb_private;

static uint32_t g_initialize_count = 0;

// Use a singleton function for g_local_platform_sp to avoid init
// constructors since LLDB is often part of a shared library
static PlatformSP &GetHostPlatformSP() {
  static PlatformSP g_platform_sp;
  return g_platform_sp;
}

const char *Platform::GetHostPlatformName() { return "host"; }

namespace {

PropertyDefinition g_properties[] = {
    {"use-module-cache", OptionValue::eTypeBoolean, true, true, nullptr,
     nullptr, "Use module cache."},
    {"module-cache-directory", OptionValue::eTypeFileSpec, true, 0, nullptr,
     nullptr, "Root directory for cached modules."},
    {nullptr, OptionValue::eTypeInvalid, false, 0, nullptr, nullptr, nullptr}};

enum { ePropertyUseModuleCache, ePropertyModuleCacheDirectory };

} // namespace

ConstString PlatformProperties::GetSettingName() {
  static ConstString g_setting_name("platform");
  return g_setting_name;
}

PlatformProperties::PlatformProperties() {
  m_collection_sp.reset(new OptionValueProperties(GetSettingName()));
  m_collection_sp->Initialize(g_properties);

  auto module_cache_dir = GetModuleCacheDirectory();
  if (module_cache_dir)
    return;

  llvm::SmallString<64> user_home_dir;
  if (!llvm::sys::path::home_directory(user_home_dir))
    return;

  module_cache_dir = FileSpec(user_home_dir.c_str(), false);
  module_cache_dir.AppendPathComponent(".lldb");
  module_cache_dir.AppendPathComponent("module_cache");
  SetModuleCacheDirectory(module_cache_dir);
}

bool PlatformProperties::GetUseModuleCache() const {
  const auto idx = ePropertyUseModuleCache;
  return m_collection_sp->GetPropertyAtIndexAsBoolean(
      nullptr, idx, g_properties[idx].default_uint_value != 0);
}

bool PlatformProperties::SetUseModuleCache(bool use_module_cache) {
  return m_collection_sp->SetPropertyAtIndexAsBoolean(
      nullptr, ePropertyUseModuleCache, use_module_cache);
}

FileSpec PlatformProperties::GetModuleCacheDirectory() const {
  return m_collection_sp->GetPropertyAtIndexAsFileSpec(
      nullptr, ePropertyModuleCacheDirectory);
}

bool PlatformProperties::SetModuleCacheDirectory(const FileSpec &dir_spec) {
  return m_collection_sp->SetPropertyAtIndexAsFileSpec(
      nullptr, ePropertyModuleCacheDirectory, dir_spec);
}

//------------------------------------------------------------------
/// Get the native host platform plug-in.
///
/// There should only be one of these for each host that LLDB runs
/// upon that should be statically compiled in and registered using
/// preprocessor macros or other similar build mechanisms.
///
/// This platform will be used as the default platform when launching
/// or attaching to processes unless another platform is specified.
//------------------------------------------------------------------
PlatformSP Platform::GetHostPlatform() { return GetHostPlatformSP(); }

static std::vector<PlatformSP> &GetPlatformList() {
  static std::vector<PlatformSP> g_platform_list;
  return g_platform_list;
}

static std::recursive_mutex &GetPlatformListMutex() {
  static std::recursive_mutex g_mutex;
  return g_mutex;
}

void Platform::Initialize() { g_initialize_count++; }

void Platform::Terminate() {
  if (g_initialize_count > 0) {
    if (--g_initialize_count == 0) {
      std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
      GetPlatformList().clear();
    }
  }
}

const PlatformPropertiesSP &Platform::GetGlobalPlatformProperties() {
  static const auto g_settings_sp(std::make_shared<PlatformProperties>());
  return g_settings_sp;
}

void Platform::SetHostPlatform(const lldb::PlatformSP &platform_sp) {
  // The native platform should use its static void Platform::Initialize()
  // function to register itself as the native platform.
  GetHostPlatformSP() = platform_sp;

  if (platform_sp) {
    std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
    GetPlatformList().push_back(platform_sp);
  }
}

Error Platform::GetFileWithUUID(const FileSpec &platform_file,
                                const UUID *uuid_ptr, FileSpec &local_file) {
  // Default to the local case
  local_file = platform_file;
  return Error();
}

FileSpecList
Platform::LocateExecutableScriptingResources(Target *target, Module &module,
                                             Stream *feedback_stream) {
  return FileSpecList();
}

// PlatformSP
// Platform::FindPlugin (Process *process, const ConstString &plugin_name)
//{
//    PlatformCreateInstance create_callback = nullptr;
//    if (plugin_name)
//    {
//        create_callback  =
//        PluginManager::GetPlatformCreateCallbackForPluginName (plugin_name);
//        if (create_callback)
//        {
//            ArchSpec arch;
//            if (process)
//            {
//                arch = process->GetTarget().GetArchitecture();
//            }
//            PlatformSP platform_sp(create_callback(process, &arch));
//            if (platform_sp)
//                return platform_sp;
//        }
//    }
//    else
//    {
//        for (uint32_t idx = 0; (create_callback =
//        PluginManager::GetPlatformCreateCallbackAtIndex(idx)) != nullptr;
//        ++idx)
//        {
//            PlatformSP platform_sp(create_callback(process, nullptr));
//            if (platform_sp)
//                return platform_sp;
//        }
//    }
//    return PlatformSP();
//}

Error Platform::GetSharedModule(const ModuleSpec &module_spec, Process *process,
                                ModuleSP &module_sp,
                                const FileSpecList *module_search_paths_ptr,
                                ModuleSP *old_module_sp_ptr,
                                bool *did_create_ptr) {
  if (IsHost())
    return ModuleList::GetSharedModule(
        module_spec, module_sp, module_search_paths_ptr, old_module_sp_ptr,
        did_create_ptr, false);

  return GetRemoteSharedModule(module_spec, process, module_sp,
                               [&](const ModuleSpec &spec) {
                                 Error error = ModuleList::GetSharedModule(
                                     spec, module_sp, module_search_paths_ptr,
                                     old_module_sp_ptr, did_create_ptr, false);
                                 if (error.Success() && module_sp)
                                   module_sp->SetPlatformFileSpec(
                                       spec.GetFileSpec());
                                 return error;
                               },
                               did_create_ptr);
}

bool Platform::GetModuleSpec(const FileSpec &module_file_spec,
                             const ArchSpec &arch, ModuleSpec &module_spec) {
  ModuleSpecList module_specs;
  if (ObjectFile::GetModuleSpecifications(module_file_spec, 0, 0,
                                          module_specs) == 0)
    return false;

  ModuleSpec matched_module_spec;
  return module_specs.FindMatchingModuleSpec(ModuleSpec(module_file_spec, arch),
                                             module_spec);
}

PlatformSP Platform::Find(const ConstString &name) {
  if (name) {
    static ConstString g_host_platform_name("host");
    if (name == g_host_platform_name)
      return GetHostPlatform();

    std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
    for (const auto &platform_sp : GetPlatformList()) {
      if (platform_sp->GetName() == name)
        return platform_sp;
    }
  }
  return PlatformSP();
}

PlatformSP Platform::Create(const ConstString &name, Error &error) {
  PlatformCreateInstance create_callback = nullptr;
  lldb::PlatformSP platform_sp;
  if (name) {
    static ConstString g_host_platform_name("host");
    if (name == g_host_platform_name)
      return GetHostPlatform();

    create_callback =
        PluginManager::GetPlatformCreateCallbackForPluginName(name);
    if (create_callback)
      platform_sp = create_callback(true, nullptr);
    else
      error.SetErrorStringWithFormat(
          "unable to find a plug-in for the platform named \"%s\"",
          name.GetCString());
  } else
    error.SetErrorString("invalid platform name");

  if (platform_sp) {
    std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
    GetPlatformList().push_back(platform_sp);
  }

  return platform_sp;
}

PlatformSP Platform::Create(const ArchSpec &arch, ArchSpec *platform_arch_ptr,
                            Error &error) {
  lldb::PlatformSP platform_sp;
  if (arch.IsValid()) {
    // Scope for locker
    {
      // First try exact arch matches across all platforms already created
      std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
      for (const auto &platform_sp : GetPlatformList()) {
        if (platform_sp->IsCompatibleArchitecture(arch, true,
                                                  platform_arch_ptr))
          return platform_sp;
      }

      // Next try compatible arch matches across all platforms already created
      for (const auto &platform_sp : GetPlatformList()) {
        if (platform_sp->IsCompatibleArchitecture(arch, false,
                                                  platform_arch_ptr))
          return platform_sp;
      }
    }

    PlatformCreateInstance create_callback;
    // First try exact arch matches across all platform plug-ins
    uint32_t idx;
    for (idx = 0; (create_callback =
                       PluginManager::GetPlatformCreateCallbackAtIndex(idx));
         ++idx) {
      if (create_callback) {
        platform_sp = create_callback(false, &arch);
        if (platform_sp &&
            platform_sp->IsCompatibleArchitecture(arch, true,
                                                  platform_arch_ptr)) {
          std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
          GetPlatformList().push_back(platform_sp);
          return platform_sp;
        }
      }
    }
    // Next try compatible arch matches across all platform plug-ins
    for (idx = 0; (create_callback =
                       PluginManager::GetPlatformCreateCallbackAtIndex(idx));
         ++idx) {
      if (create_callback) {
        platform_sp = create_callback(false, &arch);
        if (platform_sp &&
            platform_sp->IsCompatibleArchitecture(arch, false,
                                                  platform_arch_ptr)) {
          std::lock_guard<std::recursive_mutex> guard(GetPlatformListMutex());
          GetPlatformList().push_back(platform_sp);
          return platform_sp;
        }
      }
    }
  } else
    error.SetErrorString("invalid platform name");
  if (platform_arch_ptr)
    platform_arch_ptr->Clear();
  platform_sp.reset();
  return platform_sp;
}

//------------------------------------------------------------------
/// Default Constructor
//------------------------------------------------------------------
Platform::Platform(bool is_host)
    : m_is_host(is_host), m_os_version_set_while_connected(false),
      m_system_arch_set_while_connected(false), m_sdk_sysroot(), m_sdk_build(),
      m_working_dir(), m_remote_url(), m_name(), m_major_os_version(UINT32_MAX),
      m_minor_os_version(UINT32_MAX), m_update_os_version(UINT32_MAX),
      m_system_arch(), m_mutex(), m_uid_map(), m_gid_map(),
      m_max_uid_name_len(0), m_max_gid_name_len(0), m_supports_rsync(false),
      m_rsync_opts(), m_rsync_prefix(), m_supports_ssh(false), m_ssh_opts(),
      m_ignores_remote_hostname(false), m_trap_handlers(),
      m_calculated_trap_handlers(false),
      m_module_cache(llvm::make_unique<ModuleCache>()) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
  if (log)
    log->Printf("%p Platform::Platform()", static_cast<void *>(this));
}

//------------------------------------------------------------------
/// Destructor.
///
/// The destructor is virtual since this class is designed to be
/// inherited from by the plug-in instance.
//------------------------------------------------------------------
Platform::~Platform() {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
  if (log)
    log->Printf("%p Platform::~Platform()", static_cast<void *>(this));
}

void Platform::GetStatus(Stream &strm) {
  uint32_t major = UINT32_MAX;
  uint32_t minor = UINT32_MAX;
  uint32_t update = UINT32_MAX;
  std::string s;
  strm.Printf("  Platform: %s\n", GetPluginName().GetCString());

  ArchSpec arch(GetSystemArchitecture());
  if (arch.IsValid()) {
    if (!arch.GetTriple().str().empty()) {
      strm.Printf("    Triple: ");
      arch.DumpTriple(strm);
      strm.EOL();
    }
  }

  if (GetOSVersion(major, minor, update)) {
    strm.Printf("OS Version: %u", major);
    if (minor != UINT32_MAX)
      strm.Printf(".%u", minor);
    if (update != UINT32_MAX)
      strm.Printf(".%u", update);

    if (GetOSBuildString(s))
      strm.Printf(" (%s)", s.c_str());

    strm.EOL();
  }

  if (GetOSKernelDescription(s))
    strm.Printf("    Kernel: %s\n", s.c_str());

  if (IsHost()) {
    strm.Printf("  Hostname: %s\n", GetHostname());
  } else {
    const bool is_connected = IsConnected();
    if (is_connected)
      strm.Printf("  Hostname: %s\n", GetHostname());
    strm.Printf(" Connected: %s\n", is_connected ? "yes" : "no");
  }

  if (GetWorkingDirectory()) {
    strm.Printf("WorkingDir: %s\n", GetWorkingDirectory().GetCString());
  }
  if (!IsConnected())
    return;

  std::string specific_info(GetPlatformSpecificConnectionInformation());

  if (!specific_info.empty())
    strm.Printf("Platform-specific connection: %s\n", specific_info.c_str());
}

bool Platform::GetOSVersion(uint32_t &major, uint32_t &minor, uint32_t &update,
                            Process *process) {
  std::lock_guard<std::mutex> guard(m_mutex);

  bool success = m_major_os_version != UINT32_MAX;
  if (IsHost()) {
    if (!success) {
      // We have a local host platform
      success = HostInfo::GetOSVersion(m_major_os_version, m_minor_os_version,
                                       m_update_os_version);
      m_os_version_set_while_connected = success;
    }
  } else {
    // We have a remote platform. We can only fetch the remote
    // OS version if we are connected, and we don't want to do it
    // more than once.

    const bool is_connected = IsConnected();

    bool fetch = false;
    if (success) {
      // We have valid OS version info, check to make sure it wasn't
      // manually set prior to connecting. If it was manually set prior
      // to connecting, then lets fetch the actual OS version info
      // if we are now connected.
      if (is_connected && !m_os_version_set_while_connected)
        fetch = true;
    } else {
      // We don't have valid OS version info, fetch it if we are connected
      fetch = is_connected;
    }

    if (fetch) {
      success = GetRemoteOSVersion();
      m_os_version_set_while_connected = success;
    }
  }

  if (success) {
    major = m_major_os_version;
    minor = m_minor_os_version;
    update = m_update_os_version;
  } else if (process) {
    // Check with the process in case it can answer the question if
    // a process was provided
    return process->GetHostOSVersion(major, minor, update);
  }
  return success;
}

bool Platform::GetOSBuildString(std::string &s) {
  s.clear();

  if (IsHost())
#if !defined(__linux__)
    return HostInfo::GetOSBuildString(s);
#else
    return false;
#endif
  else
    return GetRemoteOSBuildString(s);
}

bool Platform::GetOSKernelDescription(std::string &s) {
  if (IsHost())
#if !defined(__linux__)
    return HostInfo::GetOSKernelDescription(s);
#else
    return false;
#endif
  else
    return GetRemoteOSKernelDescription(s);
}

void Platform::AddClangModuleCompilationOptions(
    Target *target, std::vector<std::string> &options) {
  std::vector<std::string> default_compilation_options = {
      "-x", "c++", "-Xclang", "-nostdsysteminc", "-Xclang", "-nostdsysteminc"};

  options.insert(options.end(), default_compilation_options.begin(),
                 default_compilation_options.end());
}

FileSpec Platform::GetWorkingDirectory() {
  if (IsHost()) {
    llvm::SmallString<64> cwd;
    if (llvm::sys::fs::current_path(cwd))
      return FileSpec{};
    else
      return FileSpec(cwd, true);
  } else {
    if (!m_working_dir)
      m_working_dir = GetRemoteWorkingDirectory();
    return m_working_dir;
  }
}

struct RecurseCopyBaton {
  const FileSpec &dst;
  Platform *platform_ptr;
  Error error;
};

static FileSpec::EnumerateDirectoryResult
RecurseCopy_Callback(void *baton, FileSpec::FileType file_type,
                     const FileSpec &src) {
  RecurseCopyBaton *rc_baton = (RecurseCopyBaton *)baton;
  switch (file_type) {
  case FileSpec::eFileTypePipe:
  case FileSpec::eFileTypeSocket:
    // we have no way to copy pipes and sockets - ignore them and continue
    return FileSpec::eEnumerateDirectoryResultNext;
    break;

  case FileSpec::eFileTypeDirectory: {
    // make the new directory and get in there
    FileSpec dst_dir = rc_baton->dst;
    if (!dst_dir.GetFilename())
      dst_dir.GetFilename() = src.GetLastPathComponent();
    Error error = rc_baton->platform_ptr->MakeDirectory(
        dst_dir, lldb::eFilePermissionsDirectoryDefault);
    if (error.Fail()) {
      rc_baton->error.SetErrorStringWithFormat(
          "unable to setup directory %s on remote end", dst_dir.GetCString());
      return FileSpec::eEnumerateDirectoryResultQuit; // got an error, bail out
    }

    // now recurse
    std::string src_dir_path(src.GetPath());

    // Make a filespec that only fills in the directory of a FileSpec so
    // when we enumerate we can quickly fill in the filename for dst copies
    FileSpec recurse_dst;
    recurse_dst.GetDirectory().SetCString(dst_dir.GetPath().c_str());
    RecurseCopyBaton rc_baton2 = {recurse_dst, rc_baton->platform_ptr, Error()};
    FileSpec::EnumerateDirectory(src_dir_path, true, true, true,
                                 RecurseCopy_Callback, &rc_baton2);
    if (rc_baton2.error.Fail()) {
      rc_baton->error.SetErrorString(rc_baton2.error.AsCString());
      return FileSpec::eEnumerateDirectoryResultQuit; // got an error, bail out
    }
    return FileSpec::eEnumerateDirectoryResultNext;
  } break;

  case FileSpec::eFileTypeSymbolicLink: {
    // copy the file and keep going
    FileSpec dst_file = rc_baton->dst;
    if (!dst_file.GetFilename())
      dst_file.GetFilename() = src.GetFilename();

    FileSpec src_resolved;

    rc_baton->error = FileSystem::Readlink(src, src_resolved);

    if (rc_baton->error.Fail())
      return FileSpec::eEnumerateDirectoryResultQuit; // got an error, bail out

    rc_baton->error =
        rc_baton->platform_ptr->CreateSymlink(dst_file, src_resolved);

    if (rc_baton->error.Fail())
      return FileSpec::eEnumerateDirectoryResultQuit; // got an error, bail out

    return FileSpec::eEnumerateDirectoryResultNext;
  } break;

  case FileSpec::eFileTypeRegular: {
    // copy the file and keep going
    FileSpec dst_file = rc_baton->dst;
    if (!dst_file.GetFilename())
      dst_file.GetFilename() = src.GetFilename();
    Error err = rc_baton->platform_ptr->PutFile(src, dst_file);
    if (err.Fail()) {
      rc_baton->error.SetErrorString(err.AsCString());
      return FileSpec::eEnumerateDirectoryResultQuit; // got an error, bail out
    }
    return FileSpec::eEnumerateDirectoryResultNext;
  } break;

  case FileSpec::eFileTypeInvalid:
  case FileSpec::eFileTypeOther:
  case FileSpec::eFileTypeUnknown:
    rc_baton->error.SetErrorStringWithFormat(
        "invalid file detected during copy: %s", src.GetPath().c_str());
    return FileSpec::eEnumerateDirectoryResultQuit; // got an error, bail out
    break;
  }
  llvm_unreachable("Unhandled FileSpec::FileType!");
}

Error Platform::Install(const FileSpec &src, const FileSpec &dst) {
  Error error;

  Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
  if (log)
    log->Printf("Platform::Install (src='%s', dst='%s')", src.GetPath().c_str(),
                dst.GetPath().c_str());
  FileSpec fixed_dst(dst);

  if (!fixed_dst.GetFilename())
    fixed_dst.GetFilename() = src.GetFilename();

  FileSpec working_dir = GetWorkingDirectory();

  if (dst) {
    if (dst.GetDirectory()) {
      const char first_dst_dir_char = dst.GetDirectory().GetCString()[0];
      if (first_dst_dir_char == '/' || first_dst_dir_char == '\\') {
        fixed_dst.GetDirectory() = dst.GetDirectory();
      }
      // If the fixed destination file doesn't have a directory yet,
      // then we must have a relative path. We will resolve this relative
      // path against the platform's working directory
      if (!fixed_dst.GetDirectory()) {
        FileSpec relative_spec;
        std::string path;
        if (working_dir) {
          relative_spec = working_dir;
          relative_spec.AppendPathComponent(dst.GetPath());
          fixed_dst.GetDirectory() = relative_spec.GetDirectory();
        } else {
          error.SetErrorStringWithFormat(
              "platform working directory must be valid for relative path '%s'",
              dst.GetPath().c_str());
          return error;
        }
      }
    } else {
      if (working_dir) {
        fixed_dst.GetDirectory().SetCString(working_dir.GetCString());
      } else {
        error.SetErrorStringWithFormat(
            "platform working directory must be valid for relative path '%s'",
            dst.GetPath().c_str());
        return error;
      }
    }
  } else {
    if (working_dir) {
      fixed_dst.GetDirectory().SetCString(working_dir.GetCString());
    } else {
      error.SetErrorStringWithFormat("platform working directory must be valid "
                                     "when destination directory is empty");
      return error;
    }
  }

  if (log)
    log->Printf("Platform::Install (src='%s', dst='%s') fixed_dst='%s'",
                src.GetPath().c_str(), dst.GetPath().c_str(),
                fixed_dst.GetPath().c_str());

  if (GetSupportsRSync()) {
    error = PutFile(src, dst);
  } else {
    switch (src.GetFileType()) {
    case FileSpec::eFileTypeDirectory: {
      if (GetFileExists(fixed_dst))
        Unlink(fixed_dst);
      uint32_t permissions = src.GetPermissions();
      if (permissions == 0)
        permissions = eFilePermissionsDirectoryDefault;
      error = MakeDirectory(fixed_dst, permissions);
      if (error.Success()) {
        // Make a filespec that only fills in the directory of a FileSpec so
        // when we enumerate we can quickly fill in the filename for dst copies
        FileSpec recurse_dst;
        recurse_dst.GetDirectory().SetCString(fixed_dst.GetCString());
        std::string src_dir_path(src.GetPath());
        RecurseCopyBaton baton = {recurse_dst, this, Error()};
        FileSpec::EnumerateDirectory(src_dir_path, true, true, true,
                                     RecurseCopy_Callback, &baton);
        return baton.error;
      }
    } break;

    case FileSpec::eFileTypeRegular:
      if (GetFileExists(fixed_dst))
        Unlink(fixed_dst);
      error = PutFile(src, fixed_dst);
      break;

    case FileSpec::eFileTypeSymbolicLink: {
      if (GetFileExists(fixed_dst))
        Unlink(fixed_dst);
      FileSpec src_resolved;
      error = FileSystem::Readlink(src, src_resolved);
      if (error.Success())
        error = CreateSymlink(dst, src_resolved);
    } break;
    case FileSpec::eFileTypePipe:
      error.SetErrorString("platform install doesn't handle pipes");
      break;
    case FileSpec::eFileTypeSocket:
      error.SetErrorString("platform install doesn't handle sockets");
      break;
    case FileSpec::eFileTypeInvalid:
    case FileSpec::eFileTypeUnknown:
    case FileSpec::eFileTypeOther:
      error.SetErrorString(
          "platform install doesn't handle non file or directory items");
      break;
    }
  }
  return error;
}

bool Platform::SetWorkingDirectory(const FileSpec &file_spec) {
  if (IsHost()) {
    Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
    LLDB_LOG(log, "{0}", file_spec);
    if (std::error_code ec = llvm::sys::fs::set_current_path(file_spec.GetPath())) {
      LLDB_LOG(log, "error: {0}", ec.message());
      return false;
    }
    return true;
  } else {
    m_working_dir.Clear();
    return SetRemoteWorkingDirectory(file_spec);
  }
}

Error Platform::MakeDirectory(const FileSpec &file_spec, uint32_t permissions) {
  if (IsHost())
    return FileSystem::MakeDirectory(file_spec, permissions);
  else {
    Error error;
    error.SetErrorStringWithFormat("remote platform %s doesn't support %s",
                                   GetPluginName().GetCString(),
                                   LLVM_PRETTY_FUNCTION);
    return error;
  }
}

Error Platform::GetFilePermissions(const FileSpec &file_spec,
                                   uint32_t &file_permissions) {
  if (IsHost())
    return FileSystem::GetFilePermissions(file_spec, file_permissions);
  else {
    Error error;
    error.SetErrorStringWithFormat("remote platform %s doesn't support %s",
                                   GetPluginName().GetCString(),
                                   LLVM_PRETTY_FUNCTION);
    return error;
  }
}

Error Platform::SetFilePermissions(const FileSpec &file_spec,
                                   uint32_t file_permissions) {
  if (IsHost())
    return FileSystem::SetFilePermissions(file_spec, file_permissions);
  else {
    Error error;
    error.SetErrorStringWithFormat("remote platform %s doesn't support %s",
                                   GetPluginName().GetCString(),
                                   LLVM_PRETTY_FUNCTION);
    return error;
  }
}

ConstString Platform::GetName() { return GetPluginName(); }

const char *Platform::GetHostname() {
  if (IsHost())
    return "127.0.0.1";

  if (m_name.empty())
    return nullptr;
  return m_name.c_str();
}

ConstString Platform::GetFullNameForDylib(ConstString basename) {
  return basename;
}

bool Platform::SetRemoteWorkingDirectory(const FileSpec &working_dir) {
  Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
  if (log)
    log->Printf("Platform::SetRemoteWorkingDirectory('%s')",
                working_dir.GetCString());
  m_working_dir = working_dir;
  return true;
}

const char *Platform::GetUserName(uint32_t uid) {
#if !defined(LLDB_DISABLE_POSIX)
  const char *user_name = GetCachedUserName(uid);
  if (user_name)
    return user_name;
  if (IsHost()) {
    std::string name;
    if (HostInfo::LookupUserName(uid, name))
      return SetCachedUserName(uid, name.c_str(), name.size());
  }
#endif
  return nullptr;
}

const char *Platform::GetGroupName(uint32_t gid) {
#if !defined(LLDB_DISABLE_POSIX)
  const char *group_name = GetCachedGroupName(gid);
  if (group_name)
    return group_name;
  if (IsHost()) {
    std::string name;
    if (HostInfo::LookupGroupName(gid, name))
      return SetCachedGroupName(gid, name.c_str(), name.size());
  }
#endif
  return nullptr;
}

bool Platform::SetOSVersion(uint32_t major, uint32_t minor, uint32_t update) {
  if (IsHost()) {
    // We don't need anyone setting the OS version for the host platform,
    // we should be able to figure it out by calling
    // HostInfo::GetOSVersion(...).
    return false;
  } else {
    // We have a remote platform, allow setting the target OS version if
    // we aren't connected, since if we are connected, we should be able to
    // request the remote OS version from the connected platform.
    if (IsConnected())
      return false;
    else {
      // We aren't connected and we might want to set the OS version
      // ahead of time before we connect so we can peruse files and
      // use a local SDK or PDK cache of support files to disassemble
      // or do other things.
      m_major_os_version = major;
      m_minor_os_version = minor;
      m_update_os_version = update;
      return true;
    }
  }
  return false;
}

Error Platform::ResolveExecutable(const ModuleSpec &module_spec,
                                  lldb::ModuleSP &exe_module_sp,
                                  const FileSpecList *module_search_paths_ptr) {
  Error error;
  if (module_spec.GetFileSpec().Exists()) {
    if (module_spec.GetArchitecture().IsValid()) {
      error = ModuleList::GetSharedModule(module_spec, exe_module_sp,
                                          module_search_paths_ptr, nullptr,
                                          nullptr);
    } else {
      // No valid architecture was specified, ask the platform for
      // the architectures that we should be using (in the correct order)
      // and see if we can find a match that way
      ModuleSpec arch_module_spec(module_spec);
      for (uint32_t idx = 0; GetSupportedArchitectureAtIndex(
               idx, arch_module_spec.GetArchitecture());
           ++idx) {
        error = ModuleList::GetSharedModule(arch_module_spec, exe_module_sp,
                                            module_search_paths_ptr, nullptr,
                                            nullptr);
        // Did we find an executable using one of the
        if (error.Success() && exe_module_sp)
          break;
      }
    }
  } else {
    error.SetErrorStringWithFormat("'%s' does not exist",
                                   module_spec.GetFileSpec().GetPath().c_str());
  }
  return error;
}

Error Platform::ResolveSymbolFile(Target &target, const ModuleSpec &sym_spec,
                                  FileSpec &sym_file) {
  Error error;
  if (sym_spec.GetSymbolFileSpec().Exists())
    sym_file = sym_spec.GetSymbolFileSpec();
  else
    error.SetErrorString("unable to resolve symbol file");
  return error;
}

bool Platform::ResolveRemotePath(const FileSpec &platform_path,
                                 FileSpec &resolved_platform_path) {
  resolved_platform_path = platform_path;
  return resolved_platform_path.ResolvePath();
}

const ArchSpec &Platform::GetSystemArchitecture() {
  if (IsHost()) {
    if (!m_system_arch.IsValid()) {
      // We have a local host platform
      m_system_arch = HostInfo::GetArchitecture();
      m_system_arch_set_while_connected = m_system_arch.IsValid();
    }
  } else {
    // We have a remote platform. We can only fetch the remote
    // system architecture if we are connected, and we don't want to do it
    // more than once.

    const bool is_connected = IsConnected();

    bool fetch = false;
    if (m_system_arch.IsValid()) {
      // We have valid OS version info, check to make sure it wasn't
      // manually set prior to connecting. If it was manually set prior
      // to connecting, then lets fetch the actual OS version info
      // if we are now connected.
      if (is_connected && !m_system_arch_set_while_connected)
        fetch = true;
    } else {
      // We don't have valid OS version info, fetch it if we are connected
      fetch = is_connected;
    }

    if (fetch) {
      m_system_arch = GetRemoteSystemArchitecture();
      m_system_arch_set_while_connected = m_system_arch.IsValid();
    }
  }
  return m_system_arch;
}

Error Platform::ConnectRemote(Args &args) {
  Error error;
  if (IsHost())
    error.SetErrorStringWithFormat("The currently selected platform (%s) is "
                                   "the host platform and is always connected.",
                                   GetPluginName().GetCString());
  else
    error.SetErrorStringWithFormat(
        "Platform::ConnectRemote() is not supported by %s",
        GetPluginName().GetCString());
  return error;
}

Error Platform::DisconnectRemote() {
  Error error;
  if (IsHost())
    error.SetErrorStringWithFormat("The currently selected platform (%s) is "
                                   "the host platform and is always connected.",
                                   GetPluginName().GetCString());
  else
    error.SetErrorStringWithFormat(
        "Platform::DisconnectRemote() is not supported by %s",
        GetPluginName().GetCString());
  return error;
}

bool Platform::GetProcessInfo(lldb::pid_t pid,
                              ProcessInstanceInfo &process_info) {
  // Take care of the host case so that each subclass can just
  // call this function to get the host functionality.
  if (IsHost())
    return Host::GetProcessInfo(pid, process_info);
  return false;
}

uint32_t Platform::FindProcesses(const ProcessInstanceInfoMatch &match_info,
                                 ProcessInstanceInfoList &process_infos) {
  // Take care of the host case so that each subclass can just
  // call this function to get the host functionality.
  uint32_t match_count = 0;
  if (IsHost())
    match_count = Host::FindProcesses(match_info, process_infos);
  return match_count;
}

Error Platform::LaunchProcess(ProcessLaunchInfo &launch_info) {
  Error error;
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PLATFORM));
  if (log)
    log->Printf("Platform::%s()", __FUNCTION__);

  // Take care of the host case so that each subclass can just
  // call this function to get the host functionality.
  if (IsHost()) {
    if (::getenv("LLDB_LAUNCH_FLAG_LAUNCH_IN_TTY"))
      launch_info.GetFlags().Set(eLaunchFlagLaunchInTTY);

    if (launch_info.GetFlags().Test(eLaunchFlagLaunchInShell)) {
      const bool is_localhost = true;
      const bool will_debug = launch_info.GetFlags().Test(eLaunchFlagDebug);
      const bool first_arg_is_full_shell_command = false;
      uint32_t num_resumes = GetResumeCountForLaunchInfo(launch_info);
      if (log) {
        const FileSpec &shell = launch_info.GetShell();
        const char *shell_str = (shell) ? shell.GetPath().c_str() : "<null>";
        log->Printf(
            "Platform::%s GetResumeCountForLaunchInfo() returned %" PRIu32
            ", shell is '%s'",
            __FUNCTION__, num_resumes, shell_str);
      }

      if (!launch_info.ConvertArgumentsForLaunchingInShell(
              error, is_localhost, will_debug, first_arg_is_full_shell_command,
              num_resumes))
        return error;
    } else if (launch_info.GetFlags().Test(eLaunchFlagShellExpandArguments)) {
      error = ShellExpandArguments(launch_info);
      if (error.Fail()) {
        error.SetErrorStringWithFormat("shell expansion failed (reason: %s). "
                                       "consider launching with 'process "
                                       "launch'.",
                                       error.AsCString("unknown"));
        return error;
      }
    }

    if (log)
      log->Printf("Platform::%s final launch_info resume count: %" PRIu32,
                  __FUNCTION__, launch_info.GetResumeCount());

    error = Host::LaunchProcess(launch_info);
  } else
    error.SetErrorString(
        "base lldb_private::Platform class can't launch remote processes");
  return error;
}

Error Platform::ShellExpandArguments(ProcessLaunchInfo &launch_info) {
  if (IsHost())
    return Host::ShellExpandArguments(launch_info);
  return Error("base lldb_private::Platform class can't expand arguments");
}

Error Platform::KillProcess(const lldb::pid_t pid) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PLATFORM));
  if (log)
    log->Printf("Platform::%s, pid %" PRIu64, __FUNCTION__, pid);

  // Try to find a process plugin to handle this Kill request.  If we can't,
  // fall back to
  // the default OS implementation.
  size_t num_debuggers = Debugger::GetNumDebuggers();
  for (size_t didx = 0; didx < num_debuggers; ++didx) {
    DebuggerSP debugger = Debugger::GetDebuggerAtIndex(didx);
    lldb_private::TargetList &targets = debugger->GetTargetList();
    for (int tidx = 0; tidx < targets.GetNumTargets(); ++tidx) {
      ProcessSP process = targets.GetTargetAtIndex(tidx)->GetProcessSP();
      if (process->GetID() == pid)
        return process->Destroy(true);
    }
  }

  if (!IsHost()) {
    return Error(
        "base lldb_private::Platform class can't kill remote processes unless "
        "they are controlled by a process plugin");
  }
  Host::Kill(pid, SIGTERM);
  return Error();
}

lldb::ProcessSP
Platform::DebugProcess(ProcessLaunchInfo &launch_info, Debugger &debugger,
                       Target *target, // Can be nullptr, if nullptr create a
                                       // new target, else use existing one
                       Error &error) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PLATFORM));
  if (log)
    log->Printf("Platform::%s entered (target %p)", __FUNCTION__,
                static_cast<void *>(target));

  ProcessSP process_sp;
  // Make sure we stop at the entry point
  launch_info.GetFlags().Set(eLaunchFlagDebug);
  // We always launch the process we are going to debug in a separate process
  // group, since then we can handle ^C interrupts ourselves w/o having to worry
  // about the target getting them as well.
  launch_info.SetLaunchInSeparateProcessGroup(true);

  // Allow any StructuredData process-bound plugins to adjust the launch info
  // if needed
  size_t i = 0;
  bool iteration_complete = false;
  // Note iteration can't simply go until a nullptr callback is returned, as
  // it is valid for a plugin to not supply a filter.
  auto get_filter_func = PluginManager::GetStructuredDataFilterCallbackAtIndex;
  for (auto filter_callback = get_filter_func(i, iteration_complete);
       !iteration_complete;
       filter_callback = get_filter_func(++i, iteration_complete)) {
    if (filter_callback) {
      // Give this ProcessLaunchInfo filter a chance to adjust the launch
      // info.
      error = (*filter_callback)(launch_info, target);
      if (!error.Success()) {
        if (log)
          log->Printf("Platform::%s() StructuredDataPlugin launch "
                      "filter failed.",
                      __FUNCTION__);
        return process_sp;
      }
    }
  }

  error = LaunchProcess(launch_info);
  if (error.Success()) {
    if (log)
      log->Printf("Platform::%s LaunchProcess() call succeeded (pid=%" PRIu64
                  ")",
                  __FUNCTION__, launch_info.GetProcessID());
    if (launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID) {
      ProcessAttachInfo attach_info(launch_info);
      process_sp = Attach(attach_info, debugger, target, error);
      if (process_sp) {
        if (log)
          log->Printf("Platform::%s Attach() succeeded, Process plugin: %s",
                      __FUNCTION__, process_sp->GetPluginName().AsCString());
        launch_info.SetHijackListener(attach_info.GetHijackListener());

        // Since we attached to the process, it will think it needs to detach
        // if the process object just goes away without an explicit call to
        // Process::Kill() or Process::Detach(), so let it know to kill the
        // process if this happens.
        process_sp->SetShouldDetach(false);

        // If we didn't have any file actions, the pseudo terminal might
        // have been used where the slave side was given as the file to
        // open for stdin/out/err after we have already opened the master
        // so we can read/write stdin/out/err.
        int pty_fd = launch_info.GetPTY().ReleaseMasterFileDescriptor();
        if (pty_fd != lldb_utility::PseudoTerminal::invalid_fd) {
          process_sp->SetSTDIOFileDescriptor(pty_fd);
        }
      } else {
        if (log)
          log->Printf("Platform::%s Attach() failed: %s", __FUNCTION__,
                      error.AsCString());
      }
    } else {
      if (log)
        log->Printf("Platform::%s LaunchProcess() returned launch_info with "
                    "invalid process id",
                    __FUNCTION__);
    }
  } else {
    if (log)
      log->Printf("Platform::%s LaunchProcess() failed: %s", __FUNCTION__,
                  error.AsCString());
  }

  return process_sp;
}

lldb::PlatformSP
Platform::GetPlatformForArchitecture(const ArchSpec &arch,
                                     ArchSpec *platform_arch_ptr) {
  lldb::PlatformSP platform_sp;
  Error error;
  if (arch.IsValid())
    platform_sp = Platform::Create(arch, platform_arch_ptr, error);
  return platform_sp;
}

//------------------------------------------------------------------
/// Lets a platform answer if it is compatible with a given
/// architecture and the target triple contained within.
//------------------------------------------------------------------
bool Platform::IsCompatibleArchitecture(const ArchSpec &arch,
                                        bool exact_arch_match,
                                        ArchSpec *compatible_arch_ptr) {
  // If the architecture is invalid, we must answer true...
  if (arch.IsValid()) {
    ArchSpec platform_arch;
    // Try for an exact architecture match first.
    if (exact_arch_match) {
      for (uint32_t arch_idx = 0;
           GetSupportedArchitectureAtIndex(arch_idx, platform_arch);
           ++arch_idx) {
        if (arch.IsExactMatch(platform_arch)) {
          if (compatible_arch_ptr)
            *compatible_arch_ptr = platform_arch;
          return true;
        }
      }
    } else {
      for (uint32_t arch_idx = 0;
           GetSupportedArchitectureAtIndex(arch_idx, platform_arch);
           ++arch_idx) {
        if (arch.IsCompatibleMatch(platform_arch)) {
          if (compatible_arch_ptr)
            *compatible_arch_ptr = platform_arch;
          return true;
        }
      }
    }
  }
  if (compatible_arch_ptr)
    compatible_arch_ptr->Clear();
  return false;
}

Error Platform::PutFile(const FileSpec &source, const FileSpec &destination,
                        uint32_t uid, uint32_t gid) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PLATFORM));
  if (log)
    log->Printf("[PutFile] Using block by block transfer....\n");

  uint32_t source_open_options =
      File::eOpenOptionRead | File::eOpenOptionCloseOnExec;
  if (source.GetFileType() == FileSpec::eFileTypeSymbolicLink)
    source_open_options |= File::eOpenOptionDontFollowSymlinks;

  File source_file(source, source_open_options, lldb::eFilePermissionsUserRW);
  Error error;
  uint32_t permissions = source_file.GetPermissions(error);
  if (permissions == 0)
    permissions = lldb::eFilePermissionsFileDefault;

  if (!source_file.IsValid())
    return Error("PutFile: unable to open source file");
  lldb::user_id_t dest_file = OpenFile(
      destination, File::eOpenOptionCanCreate | File::eOpenOptionWrite |
                       File::eOpenOptionTruncate | File::eOpenOptionCloseOnExec,
      permissions, error);
  if (log)
    log->Printf("dest_file = %" PRIu64 "\n", dest_file);

  if (error.Fail())
    return error;
  if (dest_file == UINT64_MAX)
    return Error("unable to open target file");
  lldb::DataBufferSP buffer_sp(new DataBufferHeap(1024, 0));
  uint64_t offset = 0;
  for (;;) {
    size_t bytes_read = buffer_sp->GetByteSize();
    error = source_file.Read(buffer_sp->GetBytes(), bytes_read);
    if (error.Fail() || bytes_read == 0)
      break;

    const uint64_t bytes_written =
        WriteFile(dest_file, offset, buffer_sp->GetBytes(), bytes_read, error);
    if (error.Fail())
      break;

    offset += bytes_written;
    if (bytes_written != bytes_read) {
      // We didn't write the correct number of bytes, so adjust
      // the file position in the source file we are reading from...
      source_file.SeekFromStart(offset);
    }
  }
  CloseFile(dest_file, error);

  if (uid == UINT32_MAX && gid == UINT32_MAX)
    return error;

  // TODO: ChownFile?

  return error;
}

Error Platform::GetFile(const FileSpec &source, const FileSpec &destination) {
  Error error("unimplemented");
  return error;
}

Error Platform::CreateSymlink(
    const FileSpec &src, // The name of the link is in src
    const FileSpec &dst) // The symlink points to dst
{
  Error error("unimplemented");
  return error;
}

bool Platform::GetFileExists(const lldb_private::FileSpec &file_spec) {
  return false;
}

Error Platform::Unlink(const FileSpec &path) {
  Error error("unimplemented");
  return error;
}

uint64_t Platform::ConvertMmapFlagsToPlatform(const ArchSpec &arch,
                                              unsigned flags) {
  uint64_t flags_platform = 0;
  if (flags & eMmapFlagsPrivate)
    flags_platform |= MAP_PRIVATE;
  if (flags & eMmapFlagsAnon)
    flags_platform |= MAP_ANON;
  return flags_platform;
}

lldb_private::Error Platform::RunShellCommand(
    const char *command, // Shouldn't be nullptr
    const FileSpec &
        working_dir, // Pass empty FileSpec to use the current working directory
    int *status_ptr, // Pass nullptr if you don't want the process exit status
    int *signo_ptr, // Pass nullptr if you don't want the signal that caused the
                    // process to exit
    std::string
        *command_output, // Pass nullptr if you don't want the command output
    uint32_t
        timeout_sec) // Timeout in seconds to wait for shell program to finish
{
  if (IsHost())
    return Host::RunShellCommand(command, working_dir, status_ptr, signo_ptr,
                                 command_output, timeout_sec);
  else
    return Error("unimplemented");
}

bool Platform::CalculateMD5(const FileSpec &file_spec, uint64_t &low,
                            uint64_t &high) {
  if (IsHost())
    return FileSystem::CalculateMD5(file_spec, low, high);
  else
    return false;
}

void Platform::SetLocalCacheDirectory(const char *local) {
  m_local_cache_directory.assign(local);
}

const char *Platform::GetLocalCacheDirectory() {
  return m_local_cache_directory.c_str();
}

static OptionDefinition g_rsync_option_table[] = {
    {LLDB_OPT_SET_ALL, false, "rsync", 'r', OptionParser::eNoArgument, nullptr,
     nullptr, 0, eArgTypeNone, "Enable rsync."},
    {LLDB_OPT_SET_ALL, false, "rsync-opts", 'R',
     OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeCommandName,
     "Platform-specific options required for rsync to work."},
    {LLDB_OPT_SET_ALL, false, "rsync-prefix", 'P',
     OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeCommandName,
     "Platform-specific rsync prefix put before the remote path."},
    {LLDB_OPT_SET_ALL, false, "ignore-remote-hostname", 'i',
     OptionParser::eNoArgument, nullptr, nullptr, 0, eArgTypeNone,
     "Do not automatically fill in the remote hostname when composing the "
     "rsync command."},
};

static OptionDefinition g_ssh_option_table[] = {
    {LLDB_OPT_SET_ALL, false, "ssh", 's', OptionParser::eNoArgument, nullptr,
     nullptr, 0, eArgTypeNone, "Enable SSH."},
    {LLDB_OPT_SET_ALL, false, "ssh-opts", 'S', OptionParser::eRequiredArgument,
     nullptr, nullptr, 0, eArgTypeCommandName,
     "Platform-specific options required for SSH to work."},
};

static OptionDefinition g_caching_option_table[] = {
    {LLDB_OPT_SET_ALL, false, "local-cache-dir", 'c',
     OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypePath,
     "Path in which to store local copies of files."},
};

llvm::ArrayRef<OptionDefinition> OptionGroupPlatformRSync::GetDefinitions() {
  return llvm::makeArrayRef(g_rsync_option_table);
}

void OptionGroupPlatformRSync::OptionParsingStarting(
    ExecutionContext *execution_context) {
  m_rsync = false;
  m_rsync_opts.clear();
  m_rsync_prefix.clear();
  m_ignores_remote_hostname = false;
}

lldb_private::Error
OptionGroupPlatformRSync::SetOptionValue(uint32_t option_idx,
                                         llvm::StringRef option_arg,
                                         ExecutionContext *execution_context) {
  Error error;
  char short_option = (char)GetDefinitions()[option_idx].short_option;
  switch (short_option) {
  case 'r':
    m_rsync = true;
    break;

  case 'R':
    m_rsync_opts.assign(option_arg);
    break;

  case 'P':
    m_rsync_prefix.assign(option_arg);
    break;

  case 'i':
    m_ignores_remote_hostname = true;
    break;

  default:
    error.SetErrorStringWithFormat("unrecognized option '%c'", short_option);
    break;
  }

  return error;
}

lldb::BreakpointSP
Platform::SetThreadCreationBreakpoint(lldb_private::Target &target) {
  return lldb::BreakpointSP();
}

llvm::ArrayRef<OptionDefinition> OptionGroupPlatformSSH::GetDefinitions() {
  return llvm::makeArrayRef(g_ssh_option_table);
}

void OptionGroupPlatformSSH::OptionParsingStarting(
    ExecutionContext *execution_context) {
  m_ssh = false;
  m_ssh_opts.clear();
}

lldb_private::Error
OptionGroupPlatformSSH::SetOptionValue(uint32_t option_idx,
                                       llvm::StringRef option_arg,
                                       ExecutionContext *execution_context) {
  Error error;
  char short_option = (char)GetDefinitions()[option_idx].short_option;
  switch (short_option) {
  case 's':
    m_ssh = true;
    break;

  case 'S':
    m_ssh_opts.assign(option_arg);
    break;

  default:
    error.SetErrorStringWithFormat("unrecognized option '%c'", short_option);
    break;
  }

  return error;
}

llvm::ArrayRef<OptionDefinition> OptionGroupPlatformCaching::GetDefinitions() {
  return llvm::makeArrayRef(g_caching_option_table);
}

void OptionGroupPlatformCaching::OptionParsingStarting(
    ExecutionContext *execution_context) {
  m_cache_dir.clear();
}

lldb_private::Error OptionGroupPlatformCaching::SetOptionValue(
    uint32_t option_idx, llvm::StringRef option_arg,
    ExecutionContext *execution_context) {
  Error error;
  char short_option = (char)GetDefinitions()[option_idx].short_option;
  switch (short_option) {
  case 'c':
    m_cache_dir.assign(option_arg);
    break;

  default:
    error.SetErrorStringWithFormat("unrecognized option '%c'", short_option);
    break;
  }

  return error;
}

size_t Platform::GetEnvironment(StringList &environment) {
  environment.Clear();
  return false;
}

const std::vector<ConstString> &Platform::GetTrapHandlerSymbolNames() {
  if (!m_calculated_trap_handlers) {
    std::lock_guard<std::mutex> guard(m_mutex);
    if (!m_calculated_trap_handlers) {
      CalculateTrapHandlerSymbolNames();
      m_calculated_trap_handlers = true;
    }
  }
  return m_trap_handlers;
}

Error Platform::GetCachedExecutable(ModuleSpec &module_spec,
                                    lldb::ModuleSP &module_sp,
                                    const FileSpecList *module_search_paths_ptr,
                                    Platform &remote_platform) {
  const auto platform_spec = module_spec.GetFileSpec();
  const auto error = LoadCachedExecutable(
      module_spec, module_sp, module_search_paths_ptr, remote_platform);
  if (error.Success()) {
    module_spec.GetFileSpec() = module_sp->GetFileSpec();
    module_spec.GetPlatformFileSpec() = platform_spec;
  }

  return error;
}

Error Platform::LoadCachedExecutable(
    const ModuleSpec &module_spec, lldb::ModuleSP &module_sp,
    const FileSpecList *module_search_paths_ptr, Platform &remote_platform) {
  return GetRemoteSharedModule(module_spec, nullptr, module_sp,
                               [&](const ModuleSpec &spec) {
                                 return remote_platform.ResolveExecutable(
                                     spec, module_sp, module_search_paths_ptr);
                               },
                               nullptr);
}

Error Platform::GetRemoteSharedModule(const ModuleSpec &module_spec,
                                      Process *process,
                                      lldb::ModuleSP &module_sp,
                                      const ModuleResolver &module_resolver,
                                      bool *did_create_ptr) {
  // Get module information from a target.
  ModuleSpec resolved_module_spec;
  bool got_module_spec = false;
  if (process) {
    // Try to get module information from the process
    if (process->GetModuleSpec(module_spec.GetFileSpec(),
                               module_spec.GetArchitecture(),
                               resolved_module_spec)) {
      if (module_spec.GetUUID().IsValid() == false ||
          module_spec.GetUUID() == resolved_module_spec.GetUUID()) {
        got_module_spec = true;
      }
    }
  }

  if (module_spec.GetArchitecture().IsValid() == false) {
    Error error;
    // No valid architecture was specified, ask the platform for
    // the architectures that we should be using (in the correct order)
    // and see if we can find a match that way
    ModuleSpec arch_module_spec(module_spec);
    for (uint32_t idx = 0; GetSupportedArchitectureAtIndex(
             idx, arch_module_spec.GetArchitecture());
         ++idx) {
      error = ModuleList::GetSharedModule(arch_module_spec, module_sp, nullptr,
                                          nullptr, nullptr);
      // Did we find an executable using one of the
      if (error.Success() && module_sp)
        break;
    }
    if (module_sp)
      got_module_spec = true;
  }

  if (!got_module_spec) {
    // Get module information from a target.
    if (!GetModuleSpec(module_spec.GetFileSpec(), module_spec.GetArchitecture(),
                       resolved_module_spec)) {
      if (module_spec.GetUUID().IsValid() == false ||
          module_spec.GetUUID() == resolved_module_spec.GetUUID()) {
        return module_resolver(module_spec);
      }
    }
  }

  // If we are looking for a specific UUID, make sure resolved_module_spec has
  // the same one before we search.
  if (module_spec.GetUUID().IsValid()) {
    resolved_module_spec.GetUUID() = module_spec.GetUUID();
  }

  // Trying to find a module by UUID on local file system.
  const auto error = module_resolver(resolved_module_spec);
  if (error.Fail()) {
    if (GetCachedSharedModule(resolved_module_spec, module_sp, did_create_ptr))
      return Error();
  }

  return error;
}

bool Platform::GetCachedSharedModule(const ModuleSpec &module_spec,
                                     lldb::ModuleSP &module_sp,
                                     bool *did_create_ptr) {
  if (IsHost() || !GetGlobalPlatformProperties()->GetUseModuleCache() ||
      !GetGlobalPlatformProperties()->GetModuleCacheDirectory())
    return false;

  Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);

  // Check local cache for a module.
  auto error = m_module_cache->GetAndPut(
      GetModuleCacheRoot(), GetCacheHostname(), module_spec,
      [this](const ModuleSpec &module_spec,
             const FileSpec &tmp_download_file_spec) {
        return DownloadModuleSlice(
            module_spec.GetFileSpec(), module_spec.GetObjectOffset(),
            module_spec.GetObjectSize(), tmp_download_file_spec);

      },
      [this](const ModuleSP &module_sp,
             const FileSpec &tmp_download_file_spec) {
        return DownloadSymbolFile(module_sp, tmp_download_file_spec);
      },
      module_sp, did_create_ptr);
  if (error.Success())
    return true;

  if (log)
    log->Printf("Platform::%s - module %s not found in local cache: %s",
                __FUNCTION__, module_spec.GetUUID().GetAsString().c_str(),
                error.AsCString());
  return false;
}

Error Platform::DownloadModuleSlice(const FileSpec &src_file_spec,
                                    const uint64_t src_offset,
                                    const uint64_t src_size,
                                    const FileSpec &dst_file_spec) {
  Error error;

  std::ofstream dst(dst_file_spec.GetPath(), std::ios::out | std::ios::binary);
  if (!dst.is_open()) {
    error.SetErrorStringWithFormat("unable to open destination file: %s",
                                   dst_file_spec.GetPath().c_str());
    return error;
  }

  auto src_fd = OpenFile(src_file_spec, File::eOpenOptionRead,
                         lldb::eFilePermissionsFileDefault, error);

  if (error.Fail()) {
    error.SetErrorStringWithFormat("unable to open source file: %s",
                                   error.AsCString());
    return error;
  }

  std::vector<char> buffer(1024);
  auto offset = src_offset;
  uint64_t total_bytes_read = 0;
  while (total_bytes_read < src_size) {
    const auto to_read = std::min(static_cast<uint64_t>(buffer.size()),
                                  src_size - total_bytes_read);
    const uint64_t n_read =
        ReadFile(src_fd, offset, &buffer[0], to_read, error);
    if (error.Fail())
      break;
    if (n_read == 0) {
      error.SetErrorString("read 0 bytes");
      break;
    }
    offset += n_read;
    total_bytes_read += n_read;
    dst.write(&buffer[0], n_read);
  }

  Error close_error;
  CloseFile(src_fd, close_error); // Ignoring close error.

  return error;
}

Error Platform::DownloadSymbolFile(const lldb::ModuleSP &module_sp,
                                   const FileSpec &dst_file_spec) {
  return Error(
      "Symbol file downloading not supported by the default platform.");
}

FileSpec Platform::GetModuleCacheRoot() {
  auto dir_spec = GetGlobalPlatformProperties()->GetModuleCacheDirectory();
  dir_spec.AppendPathComponent(GetName().AsCString());
  return dir_spec;
}

const char *Platform::GetCacheHostname() { return GetHostname(); }

const UnixSignalsSP &Platform::GetRemoteUnixSignals() {
  static const auto s_default_unix_signals_sp = std::make_shared<UnixSignals>();
  return s_default_unix_signals_sp;
}

const UnixSignalsSP &Platform::GetUnixSignals() {
  if (IsHost())
    return Host::GetUnixSignals();
  return GetRemoteUnixSignals();
}

uint32_t Platform::LoadImage(lldb_private::Process *process,
                             const lldb_private::FileSpec &local_file,
                             const lldb_private::FileSpec &remote_file,
                             lldb_private::Error &error) {
  if (local_file && remote_file) {
    // Both local and remote file was specified. Install the local file to the
    // given location.
    if (IsRemote() || local_file != remote_file) {
      error = Install(local_file, remote_file);
      if (error.Fail())
        return LLDB_INVALID_IMAGE_TOKEN;
    }
    return DoLoadImage(process, remote_file, error);
  }

  if (local_file) {
    // Only local file was specified. Install it to the current working
    // directory.
    FileSpec target_file = GetWorkingDirectory();
    target_file.AppendPathComponent(local_file.GetFilename().AsCString());
    if (IsRemote() || local_file != target_file) {
      error = Install(local_file, target_file);
      if (error.Fail())
        return LLDB_INVALID_IMAGE_TOKEN;
    }
    return DoLoadImage(process, target_file, error);
  }

  if (remote_file) {
    // Only remote file was specified so we don't have to do any copying
    return DoLoadImage(process, remote_file, error);
  }

  error.SetErrorString("Neither local nor remote file was specified");
  return LLDB_INVALID_IMAGE_TOKEN;
}

uint32_t Platform::DoLoadImage(lldb_private::Process *process,
                               const lldb_private::FileSpec &remote_file,
                               lldb_private::Error &error) {
  error.SetErrorString("LoadImage is not supported on the current platform");
  return LLDB_INVALID_IMAGE_TOKEN;
}

Error Platform::UnloadImage(lldb_private::Process *process,
                            uint32_t image_token) {
  return Error("UnloadImage is not supported on the current platform");
}

lldb::ProcessSP Platform::ConnectProcess(llvm::StringRef connect_url,
                                         llvm::StringRef plugin_name,
                                         lldb_private::Debugger &debugger,
                                         lldb_private::Target *target,
                                         lldb_private::Error &error) {
  error.Clear();

  if (!target) {
    TargetSP new_target_sp;
    error = debugger.GetTargetList().CreateTarget(debugger, "", "", false,
                                                  nullptr, new_target_sp);
    target = new_target_sp.get();
  }

  if (!target || error.Fail())
    return nullptr;

  debugger.GetTargetList().SetSelectedTarget(target);

  lldb::ProcessSP process_sp =
      target->CreateProcess(debugger.GetListener(), plugin_name, nullptr);
  if (!process_sp)
    return nullptr;

  error =
      process_sp->ConnectRemote(debugger.GetOutputFile().get(), connect_url);
  if (error.Fail())
    return nullptr;

  return process_sp;
}

size_t Platform::ConnectToWaitingProcesses(lldb_private::Debugger &debugger,
                                           lldb_private::Error &error) {
  error.Clear();
  return 0;
}

size_t Platform::GetSoftwareBreakpointTrapOpcode(Target &target,
                                                 BreakpointSite *bp_site) {
  ArchSpec arch = target.GetArchitecture();
  const uint8_t *trap_opcode = nullptr;
  size_t trap_opcode_size = 0;

  switch (arch.GetMachine()) {
  case llvm::Triple::aarch64: {
    static const uint8_t g_aarch64_opcode[] = {0x00, 0x00, 0x20, 0xd4};
    trap_opcode = g_aarch64_opcode;
    trap_opcode_size = sizeof(g_aarch64_opcode);
  } break;

  // TODO: support big-endian arm and thumb trap codes.
  case llvm::Triple::arm: {
    // The ARM reference recommends the use of 0xe7fddefe and 0xdefe
    // but the linux kernel does otherwise.
    static const uint8_t g_arm_breakpoint_opcode[] = {0xf0, 0x01, 0xf0, 0xe7};
    static const uint8_t g_thumb_breakpoint_opcode[] = {0x01, 0xde};

    lldb::BreakpointLocationSP bp_loc_sp(bp_site->GetOwnerAtIndex(0));
    AddressClass addr_class = eAddressClassUnknown;

    if (bp_loc_sp) {
      addr_class = bp_loc_sp->GetAddress().GetAddressClass();
      if (addr_class == eAddressClassUnknown &&
          (bp_loc_sp->GetAddress().GetFileAddress() & 1))
        addr_class = eAddressClassCodeAlternateISA;
    }

    if (addr_class == eAddressClassCodeAlternateISA) {
      trap_opcode = g_thumb_breakpoint_opcode;
      trap_opcode_size = sizeof(g_thumb_breakpoint_opcode);
    } else {
      trap_opcode = g_arm_breakpoint_opcode;
      trap_opcode_size = sizeof(g_arm_breakpoint_opcode);
    }
  } break;

  case llvm::Triple::mips:
  case llvm::Triple::mips64: {
    static const uint8_t g_hex_opcode[] = {0x00, 0x00, 0x00, 0x0d};
    trap_opcode = g_hex_opcode;
    trap_opcode_size = sizeof(g_hex_opcode);
  } break;

  case llvm::Triple::mipsel:
  case llvm::Triple::mips64el: {
    static const uint8_t g_hex_opcode[] = {0x0d, 0x00, 0x00, 0x00};
    trap_opcode = g_hex_opcode;
    trap_opcode_size = sizeof(g_hex_opcode);
  } break;

  case llvm::Triple::systemz: {
    static const uint8_t g_hex_opcode[] = {0x00, 0x01};
    trap_opcode = g_hex_opcode;
    trap_opcode_size = sizeof(g_hex_opcode);
  } break;

  case llvm::Triple::hexagon: {
    static const uint8_t g_hex_opcode[] = {0x0c, 0xdb, 0x00, 0x54};
    trap_opcode = g_hex_opcode;
    trap_opcode_size = sizeof(g_hex_opcode);
  } break;

  case llvm::Triple::ppc:
  case llvm::Triple::ppc64: {
    static const uint8_t g_ppc_opcode[] = {0x7f, 0xe0, 0x00, 0x08};
    trap_opcode = g_ppc_opcode;
    trap_opcode_size = sizeof(g_ppc_opcode);
  } break;

  case llvm::Triple::x86:
  case llvm::Triple::x86_64: {
    static const uint8_t g_i386_opcode[] = {0xCC};
    trap_opcode = g_i386_opcode;
    trap_opcode_size = sizeof(g_i386_opcode);
  } break;

  default:
    llvm_unreachable(
        "Unhandled architecture in Platform::GetSoftwareBreakpointTrapOpcode");
  }

  assert(bp_site);
  if (bp_site->SetTrapOpcode(trap_opcode, trap_opcode_size))
    return trap_opcode_size;

  return 0;
}