github.com/aloncn/graphics-go@v0.0.1/src/runtime/cgo/gcc_linux_arm64.c (about)

     1  // Copyright 2015 The Go Authors.  All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build cgo
     6  
     7  #include <pthread.h>
     8  #include <string.h>
     9  #include <signal.h>
    10  #include "libcgo.h"
    11  
    12  static void *threadentry(void*);
    13  
    14  void (*x_cgo_inittls)(void **tlsg, void **tlsbase);
    15  void (*setg_gcc)(void*);
    16  
    17  void
    18  _cgo_sys_thread_start(ThreadStart *ts)
    19  {
    20  	pthread_attr_t attr;
    21  	sigset_t ign, oset;
    22  	pthread_t p;
    23  	size_t size;
    24  	int err;
    25  
    26  	sigfillset(&ign);
    27  	pthread_sigmask(SIG_SETMASK, &ign, &oset);
    28  
    29  	// Not sure why the memset is necessary here,
    30  	// but without it, we get a bogus stack size
    31  	// out of pthread_attr_getstacksize.  C'est la Linux.
    32  	memset(&attr, 0, sizeof attr);
    33  	pthread_attr_init(&attr);
    34  	size = 0;
    35  	pthread_attr_getstacksize(&attr, &size);
    36  	// Leave stacklo=0 and set stackhi=size; mstack will do the rest.
    37  	ts->g->stackhi = size;
    38  	err = pthread_create(&p, &attr, threadentry, ts);
    39  
    40  	pthread_sigmask(SIG_SETMASK, &oset, nil);
    41  
    42  	if (err != 0) {
    43  		fatalf("pthread_create failed: %s", strerror(err));
    44  	}
    45  }
    46  
    47  extern void crosscall1(void (*fn)(void), void (*setg_gcc)(void*), void *g);
    48  static void*
    49  threadentry(void *v)
    50  {
    51  	ThreadStart ts;
    52  
    53  	ts = *(ThreadStart*)v;
    54  	free(v);
    55  
    56  	crosscall1(ts.fn, setg_gcc, (void*)ts.g);
    57  	return nil;
    58  }
    59  
    60  void
    61  x_cgo_init(G *g, void (*setg)(void*), void **tlsg, void **tlsbase)
    62  {
    63  	pthread_attr_t attr;
    64  	size_t size;
    65  
    66  	setg_gcc = setg;
    67  	pthread_attr_init(&attr);
    68  	pthread_attr_getstacksize(&attr, &size);
    69  	g->stacklo = (uintptr)&attr - size + 4096;
    70  	pthread_attr_destroy(&attr);
    71  
    72  	if (x_cgo_inittls) {
    73  		x_cgo_inittls(tlsg, tlsbase);
    74  	}
    75  }