1  /* go-cgo.c -- SWIG support routines for libgo.
       2  
       3     Copyright 2011 The Go Authors. All rights reserved.
       4     Use of this source code is governed by a BSD-style
       5     license that can be found in the LICENSE file.  */
       6  
       7  #include "runtime.h"
       8  
       9  /* Used for _cgo_wait_runtime_init_done.  This is based on code in
      10     runtime/cgo/gcc_libinit.c in the master library.  */
      11  
      12  static pthread_cond_t runtime_init_cond = PTHREAD_COND_INITIALIZER;
      13  static pthread_mutex_t runtime_init_mu = PTHREAD_MUTEX_INITIALIZER;
      14  static _Bool runtime_init_done;
      15  
      16  /* This is called by exported cgo functions to ensure that the runtime
      17     has been initialized before we enter the function.  This is needed
      18     when building with -buildmode=c-archive or similar.  */
      19  
      20  void
      21  _cgo_wait_runtime_init_done (void)
      22  {
      23    int err;
      24  
      25    if (__atomic_load_n (&runtime_init_done, __ATOMIC_ACQUIRE))
      26      return;
      27  
      28    err = pthread_mutex_lock (&runtime_init_mu);
      29    if (err != 0)
      30      abort ();
      31    while (!__atomic_load_n (&runtime_init_done, __ATOMIC_ACQUIRE))
      32      {
      33        err = pthread_cond_wait (&runtime_init_cond, &runtime_init_mu);
      34        if (err != 0)
      35  	abort ();
      36      }
      37    err = pthread_mutex_unlock (&runtime_init_mu);
      38    if (err != 0)
      39      abort ();
      40  }
      41  
      42  /* This is called by runtime_main after the Go runtime is
      43     initialized.  */
      44  
      45  void
      46  _cgo_notify_runtime_init_done (void)
      47  {
      48    int err;
      49  
      50    err = pthread_mutex_lock (&runtime_init_mu);
      51    if (err != 0)
      52      abort ();
      53    __atomic_store_n (&runtime_init_done, 1, __ATOMIC_RELEASE);
      54    err = pthread_cond_broadcast (&runtime_init_cond);
      55    if (err != 0)
      56      abort ();
      57    err = pthread_mutex_unlock (&runtime_init_mu);
      58    if (err != 0)
      59      abort ();
      60  }
      61  
      62  // runtime_iscgo is set to true if some cgo code is linked in.
      63  // This is done by a constructor in the cgo generated code.
      64  _Bool runtime_iscgo;