/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) NGINX, Inc.
 */

#ifndef _NXT_UNIX_THREAD_ID_H_INCLUDED_
#define _NXT_UNIX_THREAD_ID_H_INCLUDED_


#if (NXT_LINUX)

/*
 * Linux thread id is a pid of thread created by clone(2),
 * glibc does not provide a wrapper for gettid().
 */

typedef pid_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    return syscall(SYS_gettid);
}

#elif (NXT_FREEBSD)

/*
 * FreeBSD 9.0 provides pthread_getthreadid_np(), here is its
 * emulation.  Kernel thread id is the first field of struct pthread.
 * Although kernel exports a thread id as long type, lwpid_t is 32bit.
 * Thread id is a number above 100,000.
 */

typedef uint32_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    return (uint32_t) (*(long *) pthread_self());
}

#elif (NXT_SOLARIS)

/* Solaris pthread_t are numbers starting with 1. */

typedef pthread_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    return pthread_self();
}

#elif (NXT_MACOSX)

/*
 * MacOSX thread has two thread ids:
 *
 * 1) MacOSX 10.6 (Snow Leoprad) has pthread_threadid_np() returning
 *    an uint64_t value, which is obtained using the __thread_selfid()
 *    syscall.  It is a number above 300,000.
 */

typedef uint64_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    uint64_t  tid;

    (void) pthread_threadid_np(NULL, &tid);
    return tid;
}

/*
 * 2) Kernel thread mach_port_t returned by pthread_mach_thread_np().
 *    It is a number in range 100-100,000.
 *
 * return pthread_mach_thread_np(pthread_self());
 */

#elif (NXT_OPENBSD)

typedef pid_t  nxt_tid_t;

/* OpenBSD 3.9 getthrid(). */

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    return getthrid();
}

#elif (NXT_AIX)

/*
 * pthread_self() in main thread returns 1.
 * pthread_self() in other threads returns 258, 515, etc.
 *
 * pthread_getthrds_np(PTHRDSINFO_QUERY_TID) returns kernel tid
 * shown in "ps -ef -m -o THREAD" output.
 */

typedef tid_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    int                  err, size;
    pthread_t            pt;
    struct __pthrdsinfo  ti;

    size = 0;
    pt = pthread_self();

    err = pthread_getthrds_np(&pt, PTHRDSINFO_QUERY_TID, &ti,
                            sizeof(struct __pthrdsinfo), NULL, size);

    if (nxt_fast_path(err == 0)) {
        return ti.__pi_tid;
    }

    nxt_main_log_alert("pthread_getthrds_np(PTHRDSINFO_QUERY_TID) failed %E",
                       err);
    return 0;
}

/*
 * AIX pthread_getunique_np() returns thread unique number starting with 1.
 * OS/400 and i5/OS have pthread_getthreadid_np(), but AIX lacks their
 * counterpart.
 *
 *
 * int        tid;
 * pthread_t  pt;
 *
 * pt = pthread_self();
 * pthread_getunique_np(&pt, &tid);
 * return tid;
 */

#elif (NXT_HPUX)

/* HP-UX pthread_t are numbers starting with 1. */

typedef pthread_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    return pthread_self();
}

#else

typedef pthread_t  nxt_tid_t;

nxt_inline nxt_tid_t
nxt_thread_get_tid(void)
{
    return pthread_self();
}

#endif


NXT_EXPORT nxt_tid_t nxt_thread_tid(nxt_thread_t *thr);


/*
 * On Linux pthread_t is unsigned long integer.
 * On FreeBSD, MacOSX, NetBSD, and OpenBSD pthread_t is pointer to a struct.
 * On Solaris and AIX pthread_t is unsigned integer.
 * On HP-UX pthread_t is int.
 * On Cygwin pthread_t is pointer to void.
 * On z/OS pthread_t is "struct { char __[0x08]; }".
 */
typedef pthread_t  nxt_thread_handle_t;


#define nxt_thread_handle_clear(th)                                           \
    th = (pthread_t) 0

#define nxt_thread_handle_equal(th0, th1)                                     \
    pthread_equal(th0, th1)


#endif /* _NXT_UNIX_THREAD_ID_H_INCLUDED_ */