1 // Copyright 2009 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 #include <sys/types.h> 6 #include <pthread.h> 7 #include <signal.h> 8 #include <string.h> 9 #include "libcgo.h" 10 #include "libcgo_unix.h" 11 12 static void* threadentry(void*); 13 static void (*setg_gcc)(void*); 14 15 void 16 x_cgo_init(G *g, void (*setg)(void*)) 17 { 18 pthread_attr_t attr; 19 size_t size; 20 21 setg_gcc = setg; 22 pthread_attr_init(&attr); 23 pthread_attr_getstacksize(&attr, &size); 24 g->stacklo = (uintptr)&attr - size + 4096; 25 pthread_attr_destroy(&attr); 26 } 27 28 29 void 30 _cgo_sys_thread_start(ThreadStart *ts) 31 { 32 pthread_attr_t attr; 33 sigset_t ign, oset; 34 pthread_t p; 35 size_t size; 36 int err; 37 38 sigfillset(&ign); 39 pthread_sigmask(SIG_SETMASK, &ign, &oset); 40 41 pthread_attr_init(&attr); 42 pthread_attr_getstacksize(&attr, &size); 43 44 // Leave stacklo=0 and set stackhi=size; mstart will do the rest. 45 ts->g->stackhi = size; 46 err = _cgo_try_pthread_create(&p, &attr, threadentry, ts); 47 48 pthread_sigmask(SIG_SETMASK, &oset, nil); 49 50 if (err != 0) { 51 fprintf(stderr, "runtime/cgo: pthread_create failed: %s\n", strerror(err)); 52 abort(); 53 } 54 } 55 56 static void* 57 threadentry(void *v) 58 { 59 ThreadStart ts; 60 stack_t ss; 61 62 ts = *(ThreadStart*)v; 63 free(v); 64 65 /* 66 * Set specific keys. 67 */ 68 setg_gcc((void*)ts.g); 69 70 // On NetBSD, a new thread inherits the signal stack of the 71 // creating thread. That confuses minit, so we remove that 72 // signal stack here before calling the regular mstart. It's 73 // a bit baroque to remove a signal stack here only to add one 74 // in minit, but it's a simple change that keeps NetBSD 75 // working like other OS's. At this point all signals are 76 // blocked, so there is no race. 77 memset(&ss, 0, sizeof ss); 78 ss.ss_flags = SS_DISABLE; 79 sigaltstack(&ss, nil); 80 81 crosscall_amd64(ts.fn); 82 return nil; 83 } 84
