cgo: enable cgo on dragonfly

Enable cgo for dragonfly/386 and dragonfly/amd64.

R=golang-dev, jsing, iant, bradfitz
CC=golang-dev
https://golang.org/cl/13247046

misc/cgo/test/cthread_unix.c

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin freebsd linux netbsd openbsd
+// +build darwin dragonfly freebsd linux netbsd openbsd
 
 #include <pthread.h>
 #include "_cgo_export.h"

misc/cgo/testso/cgoso.go

@@ -8,6 +8,7 @@ package cgosotest
 // intentionally write the same LDFLAGS differently
 // to test correct handling of LDFLAGS.
 #cgo linux LDFLAGS: -L. -lcgosotest
+#cgo dragonfly LDFLAGS: -L. -l cgosotest
 #cgo freebsd LDFLAGS: -L. -l cgosotest
 #cgo openbsd LDFLAGS: -L. -l cgosotest
 #cgo netbsd LDFLAGS: -L. libcgosotest.so

src/cmd/6l/obj.c

@@ -152,6 +152,7 @@ main(int argc, char *argv[])
 			sysfatal("cannot use -linkmode=external with -H %s", headstr(HEADTYPE));
 		break;
 	case Hdarwin:
+	case Hdragonfly:
 	case Hfreebsd:
 	case Hlinux:
 	case Hnetbsd:

src/cmd/ld/lib.c

@@ -582,6 +582,16 @@ ldhostobj(void (*ld)(Biobuf*, char*, int64, char*), Biobuf *f, char *pkg, int64
 		}
 	}
 
+	// DragonFly declares errno with __thread, which results in a symbol
+	// type of R_386_TLS_GD or R_X86_64_TLSGD. The Go linker does not
+	// currently know how to handle TLS relocations, hence we have to
+	// force external linking for any libraries that link in code that
+	// uses errno. This can be removed if the Go linker ever supports
+	// these relocation types.
+	if(HEADTYPE == Hdragonfly)
+	if(strcmp(pkg, "net") == 0 || strcmp(pkg, "os/user") == 0)
+		isinternal = 0;
+
 	if(!isinternal)
 		externalobj = 1;
 

src/pkg/go/build/build.go

@@ -260,6 +260,8 @@ var Default Context = defaultContext()
 var cgoEnabled = map[string]bool{
 	"darwin/386":      true,
 	"darwin/amd64":    true,
+	"dragonfly/386":   true,
+	"dragonfly/amd64": true,
 	"freebsd/386":     true,
 	"freebsd/amd64":   true,
 	"freebsd/arm":     true,

src/pkg/os/user/lookup_unix.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin freebsd linux netbsd openbsd
+// +build darwin dragonfly freebsd linux netbsd openbsd
 // +build cgo
 
 package user

src/pkg/runtime/cgo/cgo.go

@@ -12,6 +12,7 @@ package cgo
 /*
 
 #cgo darwin LDFLAGS: -lpthread
+#cgo dragonfly LDFLAGS: -lpthread
 #cgo freebsd LDFLAGS: -lpthread
 #cgo linux LDFLAGS: -lpthread
 #cgo netbsd LDFLAGS: -lpthread

src/pkg/runtime/cgo/dragonfly.c

@@ -0,0 +1,13 @@
+// Copyright 2010 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.
+
+// Supply environ and __progname, because we don't
+// link against the standard DragonFly crt0.o and the
+// libc dynamic library needs them.
+
+char *environ[1];
+char *__progname;
+
+#pragma dynexport environ environ
+#pragma dynexport __progname __progname

src/pkg/runtime/cgo/gcc_dragonfly_386.c

@@ -0,0 +1,77 @@
+// 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 <sys/types.h>
+#include <sys/signalvar.h>
+#include <pthread.h>
+#include <signal.h>
+#include <string.h>
+#include "libcgo.h"
+
+static void* threadentry(void*);
+static void (*setmg_gcc)(void*, void*);
+
+void
+x_cgo_init(G *g, void (*setmg)(void*, void*))
+{
+	pthread_attr_t attr;
+	size_t size;
+
+	setmg_gcc = setmg;
+	pthread_attr_init(&attr);
+	pthread_attr_getstacksize(&attr, &size);
+	g->stackguard = (uintptr)&attr - size + 4096;
+	pthread_attr_destroy(&attr);
+}
+
+
+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);
+	sigprocmask(SIG_SETMASK, &ign, &oset);
+
+	pthread_attr_init(&attr);
+	pthread_attr_getstacksize(&attr, &size);
+	ts->g->stackguard = size;
+	err = pthread_create(&p, &attr, threadentry, ts);
+
+	sigprocmask(SIG_SETMASK, &oset, nil);
+
+	if (err != 0) {
+		fprintf(stderr, "runtime/cgo: pthread_create failed: %s\n", strerror(err));
+		abort();
+	}
+}
+
+static void*
+threadentry(void *v)
+{
+	ThreadStart ts;
+
+	ts = *(ThreadStart*)v;
+	free(v);
+
+	ts.g->stackbase = (uintptr)&ts;
+
+	/*
+	 * _cgo_sys_thread_start set stackguard to stack size;
+	 * change to actual guard pointer.
+	 */
+	ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
+
+	/*
+	 * Set specific keys.
+	 */
+	setmg_gcc((void*)ts.m, (void*)ts.g);
+
+	crosscall_386(ts.fn);
+	return nil;
+}

src/pkg/runtime/cgo/gcc_dragonfly_amd64.c

@@ -0,0 +1,77 @@
+// 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 <sys/types.h>
+#include <sys/signalvar.h>
+#include <pthread.h>
+#include <signal.h>
+#include <string.h>
+#include "libcgo.h"
+
+static void* threadentry(void*);
+static void (*setmg_gcc)(void*, void*);
+
+void
+x_cgo_init(G *g, void (*setmg)(void*, void*))
+{
+	pthread_attr_t attr;
+	size_t size;
+
+	setmg_gcc = setmg;
+	pthread_attr_init(&attr);
+	pthread_attr_getstacksize(&attr, &size);
+	g->stackguard = (uintptr)&attr - size + 4096;
+	pthread_attr_destroy(&attr);
+}
+
+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);
+	sigprocmask(SIG_SETMASK, &ign, &oset);
+
+	pthread_attr_init(&attr);
+	pthread_attr_getstacksize(&attr, &size);
+
+	ts->g->stackguard = size;
+	err = pthread_create(&p, &attr, threadentry, ts);
+
+	sigprocmask(SIG_SETMASK, &oset, nil);
+
+	if (err != 0) {
+		fprintf(stderr, "runtime/cgo: pthread_create failed: %s\n", strerror(err));
+		abort();
+	}
+}
+
+static void*
+threadentry(void *v)
+{
+	ThreadStart ts;
+
+	ts = *(ThreadStart*)v;
+	free(v);
+
+	ts.g->stackbase = (uintptr)&ts;
+
+	/*
+	 * _cgo_sys_thread_start set stackguard to stack size;
+	 * change to actual guard pointer.
+	 */
+	ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
+
+	/*
+	 * Set specific keys.
+	 */
+	setmg_gcc((void*)ts.m, (void*)ts.g);
+
+	crosscall_amd64(ts.fn);
+	return nil;
+}

src/pkg/runtime/cgo/gcc_setenv.c

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin freebsd linux netbsd openbsd
+// +build darwin dragonfly freebsd linux netbsd openbsd
 
 #include "libcgo.h"
 

src/pkg/runtime/cgo/setenv.c

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin freebsd linux netbsd openbsd
+// +build darwin dragonfly freebsd linux netbsd openbsd
 
 #pragma cgo_import_static x_cgo_setenv
 

src/run.bash

@@ -104,7 +104,8 @@ go run $GOROOT/test/run.go - . || exit 1
 [ "$CGO_ENABLED" != 1 ] ||
 (xcd ../misc/cgo/test
 go test -ldflags '-linkmode=auto' || exit 1
-go test -ldflags '-linkmode=internal' || exit 1
+# linkmode=internal fails on dragonfly since errno is a TLS relocation.
+[ "$GOHOSTOS" == dragonfly ] || go test -ldflags '-linkmode=internal' || exit 1
 case "$GOHOSTOS-$GOARCH" in
 openbsd-386 | openbsd-amd64)
 	# test linkmode=external, but __thread not supported, so skip testtls.
@@ -118,7 +119,7 @@ darwin-386 | darwin-amd64)
 	*) go test -ldflags '-linkmode=external'  || exit 1;;
 	esac
 	;;
-freebsd-386 | freebsd-amd64 | linux-386 | linux-amd64 | linux-arm | netbsd-386 | netbsd-amd64)
+dragonfly-386 | dragonfly-amd64 | freebsd-386 | freebsd-amd64 | linux-386 | linux-amd64 | linux-arm | netbsd-386 | netbsd-amd64)
 	go test -ldflags '-linkmode=external' || exit 1
 	go test -ldflags '-linkmode=auto' ../testtls || exit 1
 	go test -ldflags '-linkmode=external' ../testtls || exit 1