/*

  This file is part of libmicrohttpd

  Copyright (C) 2016 Karlson2k (Evgeny Grin)

  This library is free software; you can redistribute it and/or

  modify it under the terms of the GNU Lesser General Public

  License as published by the Free Software Foundation; either

  version 2.1 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,

  but WITHOUT ANY WARRANTY; without even the implied warranty of

  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public

  License along with this library; if not, write to the Free Software

  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

*/

/**

 * @file microhttpd/mhd_threads.h

 * @brief  Header for platform-independent threads abstraction

 * @author Karlson2k (Evgeny Grin)

 *

 * Provides basic abstraction for threads.

 * Any functions can be implemented as macro on some platforms

 * unless explicitly marked otherwise.

 * Any function argument can be skipped in macro, so avoid

 * variable modification in function parameters.

 *

 * @warning Unlike pthread functions, most of functions return

 *          nonzero on success.

 */

#ifndef MHD_THREADS_H

#define MHD_THREADS_H 1

#include "mhd_options.h"

#ifdef HAVE_STDDEF_H

#  include <stddef.h> /* for size_t */

#else  /* ! HAVE_STDDEF_H */

#  include <stdlib.h> /* for size_t */

#endif /* ! HAVE_STDDEF_H */

#if defined(MHD_USE_POSIX_THREADS)

#  undef HAVE_CONFIG_H

#  include <pthread.h>

#  define HAVE_CONFIG_H 1

#elif defined(MHD_USE_W32_THREADS)

#  ifndef WIN32_LEAN_AND_MEAN

#    define WIN32_LEAN_AND_MEAN 1

#  endif /* !WIN32_LEAN_AND_MEAN */

#  include <windows.h>

#else

#  error No threading API is available.

#endif

#ifndef MHD_NO_THREAD_NAMES

#  if defined(MHD_USE_POSIX_THREADS)

#    if defined(HAVE_PTHREAD_SETNAME_NP_GNU) || defined(HAVE_PTHREAD_SET_NAME_NP_FREEBSD) || \

        defined(HAVE_PTHREAD_SETNAME_NP_DARWIN) || defined(HAVE_PTHREAD_SETNAME_NP_NETBSD) || \

        defined(HAVE_PTHREAD_ATTR_SETNAME_NP_NETBSD) || defined(HAVE_PTHREAD_ATTR_SETNAME_NP_IBMI)

#      define MHD_USE_THREAD_NAME_

#    endif /* HAVE_PTHREAD_SETNAME_NP */

#  elif defined(MHD_USE_W32_THREADS)

#    ifdef _MSC_FULL_VER

       /* Thread names only available with VC compiler */

#      define MHD_USE_THREAD_NAME_

#    endif /* _MSC_FULL_VER */

#  endif

#endif

#if defined(MHD_USE_POSIX_THREADS)

  typedef pthread_t MHD_thread_handle_;

#elif defined(MHD_USE_W32_THREADS)

  typedef HANDLE MHD_thread_handle_;

#endif

#if defined(MHD_USE_POSIX_THREADS)

#  define MHD_THRD_RTRN_TYPE_ void*

#  define MHD_THRD_CALL_SPEC_

#elif defined(MHD_USE_W32_THREADS)

#  define MHD_THRD_RTRN_TYPE_ unsigned

#  define MHD_THRD_CALL_SPEC_ __stdcall

#endif

#if defined(MHD_USE_POSIX_THREADS)

  typedef pthread_t MHD_thread_ID_;

#elif defined(MHD_USE_W32_THREADS)

  typedef DWORD MHD_thread_ID_;

#endif

/* Depending on implementation, pthread_create() MAY set thread ID into

 * provided pointer and after it start thread OR start thread and after

 * if set thread ID. In latter case, to avoid data races, additional

 * pthread_self() call is required in thread routine. Is some platform

 * is known for setting thread ID BEFORE starting thread macro

 * MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD could be defined

 * to save some resources. */

#if defined(MHD_USE_POSIX_THREADS)

#  ifdef MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD

  union _MHD_thread_handle_ID_

  {

    MHD_thread_handle_  handle; /**< To be used in other threads */

    MHD_thread_ID_      ID;     /**< To be used in thread itself */

  };

  typedef union _MHD_thread_handle_ID_ MHD_thread_handle_ID_;

#  else  /* ! MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD */

  struct _MHD_thread_handle_ID_

  {

    MHD_thread_handle_  handle; /**< To be used in other threads */

    MHD_thread_ID_      ID;     /**< To be used in thread itself */

  };

  typedef struct _MHD_thread_handle_ID_ MHD_thread_handle_ID_;

#  endif /* ! MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD */

#elif defined(MHD_USE_W32_THREADS)

  struct _MHD_thread_handle_ID_

  {

    MHD_thread_handle_  handle; /**< To be used in other threads */

    MHD_thread_ID_      ID;     /**< To be used in thread itself */

  };

  typedef struct _MHD_thread_handle_ID_ MHD_thread_handle_ID_;

#endif

#if defined(MHD_USE_POSIX_THREADS)

/**

 * Wait until specified thread is ended and free thread handle on success.

 * @param thread handle to watch

 * @return nonzero on success, zero otherwise

 */

#define MHD_join_thread_(thread) (!pthread_join((thread), NULL))

#elif defined(MHD_USE_W32_THREADS)

/**

 * Wait until specified thread is ended and free thread handle on success.

 * @param thread handle to watch

 * @return nonzero on success, zero otherwise

 */

#define MHD_join_thread_(thread) (WAIT_OBJECT_0 == WaitForSingleObject((thread), INFINITE) ? (CloseHandle((thread)), !0) : 0)

#endif

#if defined(MHD_USE_POSIX_THREADS)

/**

 * Check whether provided thread ID match current thread.

 * @param ID thread ID to match

 * @return nonzero on match, zero otherwise

 */

#define MHD_thread_ID_match_current_(ID) (pthread_equal((ID), pthread_self()))

#elif defined(MHD_USE_W32_THREADS)

/**

 * Check whether provided thread ID match current thread.

 * @param ID thread ID to match

 * @return nonzero on match, zero otherwise

 */

#define MHD_thread_ID_match_current_(ID) (GetCurrentThreadId() == (ID))

#endif

#if defined(MHD_USE_POSIX_THREADS)

#  ifdef MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD

/**

 * Initialise thread ID.

 * @param thread_handle_ID_ptr pointer to thread handle-ID

 */

#define MHD_thread_init_(thread_handle_ID_ptr) (void)0

#  else  /* ! MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD */

/**

 * Initialise thread ID.

 * @param thread_handle_ID_ptr pointer to thread handle-ID

 */

#define MHD_thread_init_(thread_handle_ID_ptr) ((thread_handle_ID_ptr)->ID=pthread_self())

#  endif /* ! MHD_PTHREAD_CREATE__SET_ID_BEFORE_START_THREAD */

#elif defined(MHD_USE_W32_THREADS)

/**

 * Initialise thread ID.

 * @param thread_handle_ID_ptr pointer to thread handle-ID

 */

#define MHD_thread_init_(thread_handle_ID_ptr) ((thread_handle_ID_ptr)->ID=GetCurrentThreadId())

#endif

/**

 * Signature of main function for a thread.

 *

 * @param cls closure argument for the function

 * @return termination code from the thread

 */

typedef MHD_THRD_RTRN_TYPE_

(MHD_THRD_CALL_SPEC_ *MHD_THREAD_START_ROUTINE_)(void *cls);

/**

 * Create a thread and set the attributes according to our options.

 *

 * If thread is created, thread handle must be freed by MHD_join_thread_().

 *

 * @param thread        handle to initialize

 * @param stack_size    size of stack for new thread, 0 for default

 * @param start_routine main function of thread

 * @param arg argument  for start_routine

 * @return non-zero on success; zero otherwise

 */

int

MHD_create_thread_ (MHD_thread_handle_ID_ *thread,

                    size_t stack_size,

                    MHD_THREAD_START_ROUTINE_ start_routine,

                    void *arg);

#ifndef MHD_USE_THREAD_NAME_

#define MHD_create_named_thread_(t,n,s,r,a) MHD_create_thread_((t),(s),(r),(a))

#else  /* MHD_USE_THREAD_NAME_ */

/**

 * Create a named thread and set the attributes according to our options.

 *

 * @param thread        handle to initialize

 * @param thread_name   name for new thread

 * @param stack_size    size of stack for new thread, 0 for default

 * @param start_routine main function of thread

 * @param arg argument  for start_routine

 * @return non-zero on success; zero otherwise

 */

int

MHD_create_named_thread_ (MHD_thread_handle_ID_ *thread,

                          const char* thread_name,

                          size_t stack_size,

                          MHD_THREAD_START_ROUTINE_ start_routine,

                          void *arg);

#endif /* MHD_USE_THREAD_NAME_ */

#endif /* ! MHD_THREADS_H */