| // Copyright 2009 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> // strerror |
| #include <signal.h> |
| #include <stdlib.h> |
| #include "libcgo.h" |
| #include "libcgo_unix.h" |
| |
| static void* threadentry(void*); |
| static void (*setg_gcc)(void*); |
| |
| // This will be set in gcc_android.c for android-specific customization. |
| void (*x_cgo_inittls)(void **tlsg, void **tlsbase) __attribute__((common)); |
| |
| void |
| x_cgo_init(G *g, void (*setg)(void*), void **tlsg, void **tlsbase) |
| { |
| pthread_attr_t *attr; |
| size_t size; |
| |
| /* 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; |
| attr = (pthread_attr_t*)malloc(sizeof *attr); |
| if (attr == NULL) { |
| fatalf("malloc failed: %s", strerror(errno)); |
| } |
| pthread_attr_init(attr); |
| pthread_attr_getstacksize(attr, &size); |
| g->stacklo = (uintptr)&size - size + 4096; |
| pthread_attr_destroy(attr); |
| free(attr); |
| |
| if (x_cgo_inittls) { |
| x_cgo_inittls(tlsg, tlsbase); |
| } |
| } |
| |
| |
| 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_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)); |
| } |
| } |
| |
| static void* |
| threadentry(void *v) |
| { |
| ThreadStart ts; |
| |
| ts = *(ThreadStart*)v; |
| _cgo_tsan_acquire(); |
| free(v); |
| _cgo_tsan_release(); |
| |
| /* |
| * Set specific keys. |
| */ |
| setg_gcc((void*)ts.g); |
| |
| crosscall_amd64(ts.fn); |
| return nil; |
| } |