usSharedLibrary.cpp

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/*=============================================================================

  Library: CppMicroServices

  Copyright (c) German Cancer Research Center,
    Division of Medical and Biological Informatics

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

=============================================================================*/

#include "usSharedLibrary.h"

#include <stdexcept>

#include <usUtils_p.h>
#include <usModuleRegistry.h>
#include <usModuleActivator.h>


#if defined(US_PLATFORM_POSIX)
  #include <dlfcn.h>
#elif defined(US_PLATFORM_WINDOWS)
  #ifndef WIN32_LEAN_AND_MEAN
    #define WIN32_LEAN_AND_MEAN
  #endif
  #include <windows.h>
  #include <strsafe.h>
#else
  #error Unsupported platform
#endif


US_BEGIN_NAMESPACE

#ifdef US_PLATFORM_POSIX
static const char PATH_SEPARATOR = '/';
#else
static const char PATH_SEPARATOR = '\\';
#endif

class SharedLibraryPrivate : public SharedData
{
public:

  SharedLibraryPrivate()
    : m_Handle(NULL)
  #ifdef US_PLATFORM_WINDOWS
    , m_Suffix(".dll")
  #elif defined(US_PLATFORM_APPLE)
    , m_Suffix(".dylib")
    , m_Prefix("lib")
  #else
    , m_Suffix(".so")
    , m_Prefix("lib")
  #endif
  {}

  void* m_Handle;

  std::string m_Name;
  std::string m_Path;
  std::string m_FilePath;
  std::string m_Suffix;
  std::string m_Prefix;

};

SharedLibrary::SharedLibrary()
  : d(new SharedLibraryPrivate)
{
}

SharedLibrary::SharedLibrary(const SharedLibrary& other)
  : d(other.d)
{
}

SharedLibrary::SharedLibrary(const std::string& libPath, const std::string& name)
  : d(new SharedLibraryPrivate)
{
  d->m_Name = name;
  d->m_Path = libPath;
}

SharedLibrary::SharedLibrary(const std::string& absoluteFilePath)
  : d(new SharedLibraryPrivate)
{
  d->m_FilePath = absoluteFilePath;
  SetFilePath(absoluteFilePath);
}

SharedLibrary::~SharedLibrary()
{
}

SharedLibrary& SharedLibrary::operator =(const SharedLibrary& other)
{
  d = other.d;
  return *this;
}

void SharedLibrary::Load(int flags)
{
  if (d->m_Handle) throw std::logic_error(std::string("Library already loaded: ") + GetFilePath());
  std::string libPath = GetFilePath();
#ifdef US_PLATFORM_POSIX
  d->m_Handle = dlopen(libPath.c_str(), flags);
  if (!d->m_Handle)
  {
    const char* err = dlerror();
    throw std::runtime_error(err ? std::string(err) : (std::string("Error loading ") + libPath));
  }
#else
  d->m_Handle = LoadLibrary(libPath.c_str());
  if (!d->m_Handle)
  {
    std::string errMsg = "Loading ";
    errMsg.append(libPath).append("failed with error: ").append(GetLastErrorStr());

    throw std::runtime_error(errMsg);
  }
#endif
}

void SharedLibrary::Load()
{
#ifdef US_PLATFORM_POSIX
#ifdef US_GCC_RTTI_WORKAROUND_NEEDED
  Load(RTLD_LAZY | RTLD_GLOBAL);
#else
  Load(RTLD_LAZY | RTLD_LOCAL);
#endif
#else
  Load(0);
#endif
}

void SharedLibrary::Unload()
{
  if (d->m_Handle)
  {
#ifdef US_PLATFORM_POSIX
    if (dlclose(d->m_Handle))
    {
      const char* err = dlerror();
      throw std::runtime_error(err ? std::string(err) : (std::string("Error unloading ") + GetLibraryPath()));
    }
#else
    if (!FreeLibrary((HMODULE)d->m_Handle))
    {
      std::string errMsg = "Unloading ";
      errMsg.append(GetLibraryPath()).append("failed with error: ").append(GetLastErrorStr());

      throw std::runtime_error(errMsg);
    }
#endif
    d->m_Handle = 0;
  }
}

void SharedLibrary::SetName(const std::string& name)
{
  if (IsLoaded() || !d->m_FilePath.empty()) return;
  d.Detach();
  d->m_Name = name;
}

std::string SharedLibrary::GetName() const
{
  return d->m_Name;
}

std::string SharedLibrary::GetFilePath(const std::string& name) const
{
  if (!d->m_FilePath.empty()) return d->m_FilePath;
  return GetLibraryPath() + PATH_SEPARATOR + GetPrefix() + name + GetSuffix();
}

void SharedLibrary::SetFilePath(const std::string& absoluteFilePath)
{
  if (IsLoaded()) return;

  d.Detach();
  d->m_FilePath = absoluteFilePath;

  std::string name = d->m_FilePath;
  std::size_t pos = d->m_FilePath.find_last_of(PATH_SEPARATOR);
  if (pos != std::string::npos)
  {
    d->m_Path = d->m_FilePath.substr(0, pos);
    name = d->m_FilePath.substr(pos+1);
  }
  else
  {
    d->m_Path.clear();
  }

  if (name.size() >= d->m_Prefix.size() &&
      name.compare(0, d->m_Prefix.size(), d->m_Prefix) == 0)
  {
    name = name.substr(d->m_Prefix.size());
  }
  if (name.size() >= d->m_Suffix.size() &&
      name.compare(name.size()-d->m_Suffix.size(), d->m_Suffix.size(), d->m_Suffix) == 0)
  {
    name = name.substr(0, name.size()-d->m_Suffix.size());
  }
  d->m_Name = name;
}

std::string SharedLibrary::GetFilePath() const
{
  return GetFilePath(d->m_Name);
}

void SharedLibrary::SetLibraryPath(const std::string& path)
{
  if (IsLoaded() || !d->m_FilePath.empty()) return;
  d.Detach();
  d->m_Path = path;
}

std::string SharedLibrary::GetLibraryPath() const
{
  return d->m_Path;
}

void SharedLibrary::SetSuffix(const std::string& suffix)
{
  if (IsLoaded() || !d->m_FilePath.empty()) return;
  d.Detach();
  d->m_Suffix = suffix;
}

std::string SharedLibrary::GetSuffix() const
{
  return d->m_Suffix;
}

void SharedLibrary::SetPrefix(const std::string& prefix)
{
  if (IsLoaded() || !d->m_FilePath.empty()) return;
  d.Detach();
  d->m_Prefix = prefix;
}

std::string SharedLibrary::GetPrefix() const
{
  return d->m_Prefix;
}

void* SharedLibrary::GetHandle() const
{
  return d->m_Handle;
}

bool SharedLibrary::IsLoaded() const
{
  return d->m_Handle != NULL;
}

US_END_NAMESPACE