// Copyright 2015 The Go Authors. All rights reserved.

// Use of this source code is governed by a BSD-style

// license that can be found in the LICENSE file.

#include <pthread.h>

#include <errno.h>

#include <string.h>

#include <signal.h>

#include <stdlib.h>

#include "libcgo.h"

#include "libcgo_unix.h"

static void *threadentry(void*);

void (*x_cgo_inittls)(void **tlsg, void **tlsbase) __attribute__((common));

static void (*setg_gcc)(void*);

void

_cgo_sys_thread_start(ThreadStart *ts)

{

pthread_attr_t attr;

sigset_t ign, oset;

pthread_t p;

size_t size;

int err;

sigfillset(&ign);

pthread_sigmask(SIG_SETMASK, &ign, &oset);

pthread_attr_init(&attr);

pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

pthread_attr_getstacksize(&attr, &size);

// Leave stacklo=0 and set stackhi=size; mstart will do the rest.

ts->g->stackhi = size;

err = _cgo_try_pthread_create(&p, &attr, threadentry, ts);

pthread_sigmask(SIG_SETMASK, &oset, nil);

if (err != 0) {

fatalf("pthread_create failed: %s", strerror(err));

}

}

extern void crosscall1(void (*fn)(void), void (*setg_gcc)(void*), void *g);

static void*

threadentry(void *v)

{

ThreadStart ts;

ts = *(ThreadStart*)v;

free(v);

crosscall1(ts.fn, setg_gcc, (void*)ts.g);

return nil;

}

void

x_cgo_init(G *g, void (*setg)(void*), void **tlsg, void **tlsbase)

{

uintptr *pbounds;

/* The memory sanitizer distributed with versions of clang

before 3.8 has a bug: if you call mmap before malloc, mmap

may return an address that is later overwritten by the msan

library. Avoid this problem by forcing a call to malloc

here, before we ever call malloc.

This is only required for the memory sanitizer, so it's

unfortunate that we always run it. It should be possible

to remove this when we no longer care about versions of

clang before 3.8. The test for this is

misc/cgo/testsanitizers.

GCC works hard to eliminate a seemingly unnecessary call to

malloc, so we actually use the memory we allocate. */

setg_gcc = setg;

pbounds = (uintptr*)malloc(2 * sizeof(uintptr));

if (pbounds == NULL) {

fatalf("malloc failed: %s", strerror(errno));

}

_cgo_set_stacklo(g, pbounds);

free(pbounds);

if (x_cgo_inittls) {

x_cgo_inittls(tlsg, tlsbase);

}

}