package main

// This program hung when run under the C/C++ ThreadSanitizer.
// TSAN defers asynchronous signals until the signaled thread calls into libc.
// Since the Go runtime makes direct futex syscalls, Go runtime threads could
// run for an arbitrarily long time without triggering the libc interceptors.
// See https://golang.org/issue/18717.

import (
	"os"
	"os/signal"
	"syscall"
)

/*

char x_cgo_yield_strncpy_src = 0;
char x_cgo_yield_strncpy_dst = 0;
size_t x_cgo_yield_strncpy_n = 0;

/*
Stub for allowing libc interceptors to execute.

_cgo_yield is set to NULL if we do not expect libc interceptors to exist.
*/
static void
x_cgo_yield()
{
	/*
	The libc function(s) we call here must form a no-op and include at least one
	call that triggers TSAN to process pending asynchronous signals.

	CALL	(CTR)

	MOVD	R3, (4*8)(R14)		// r1
	MOVD	R4, (5*8)(R14)		// r2

	// Standard libc functions return -1 on error
	// and set errno.
	CMPW	R3, $-1
	BNE	ok

	// Get error code from libc.
	CALL	libc_errno(SB)
	MOVW	(R3), R3
	MOVD	R3, (6*8)(R14)		// err

ok:
	RET

// syscallX calls a function in libc on behalf of the syscall package.
// syscallX takes a pointer to a struct like:
// struct {

//go:build illumos && amd64

package unix

import (
	"unsafe"
)

//go:cgo_import_dynamic libc_readv readv "libc.so"
//go:cgo_import_dynamic libc_preadv preadv "libc.so"
//go:cgo_import_dynamic libc_writev writev "libc.so"
//go:cgo_import_dynamic libc_pwritev pwritev "libc.so"
//go:cgo_import_dynamic libc_accept4 accept4 "libsocket.so"

//go:linkname procreadv libc_readv
//go:linkname procpreadv libc_preadv

One is written in pure Go and parses /etc/passwd and /etc/group. The other
is cgo-based and relies on the standard C library (libc) routines such as
getpwuid_r, getgrnam_r, and getgrouplist.

When cgo is available, and the required routines are implemented in libc
for a particular platform, cgo-based (libc-backed) code is used.
This can be overridden by using osusergo build tag, which enforces
the pure Go implementation.
*/
package user

		// first call on an M, until that libcCall instance
		// returns.  Reentrance only matters for signals, as
		// libc never calls back into Go.  The tricky case is
		// where we call libcX from an M and record g/pc/sp.
		// Before that call returns, a signal arrives on the
		// same M and the signal handling code calls another
		// libc function.  We don't want that second libcCall
		// from within the handler to be recorded, and we

	CALL	R11

	MOVD	R0, (4*8)(R19)		// r1
	MOVD	R1, (5*8)(R19)		// r2

	// Standard libc functions return -1 on error
	// and set errno.
	CMPW	$-1, R0
	BNE	ok

	// Get error code from libc.
	CALL	libc_errno(SB)
	MOVW	(R0), R0
	MOVD	R0, (6*8)(R19)		// err

ok:
	RET

// syscallX calls a function in libc on behalf of the syscall package.
// syscallX takes a pointer to a struct like:
// struct {

	MOVW	R1, (5*4)(R8) // r2

	// Standard libc functions return -1 on error and set errno.
	CMP	$-1, R0
	BNE	ok

	// Get error code from libc.
	BL	libc_errno(SB)
	MOVW	(R0), R1
	MOVW	R1, (6*4)(R8) // err

ok:
	MOVW	$0, R0		// no error (it's ignored anyway)
	MOVW	R9, R13
	RET

// syscallX calls a function in libc on behalf of the syscall package.

openbsd_386)
	mkasm="go run mkasm.go"
	mkerrors="$mkerrors -m32"
	mksyscall="go run mksyscall.go -l32 -openbsd -libc"
	mksysctl="go run mksysctl_openbsd.go"
	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
	;;
openbsd_amd64)
	mkasm="go run mkasm.go"
	mkerrors="$mkerrors -m64"
	mksyscall="go run mksyscall.go -openbsd -libc"
	mksysctl="go run mksysctl_openbsd.go"
	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
	;;
openbsd_arm)

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

//go:build solaris

package syscall

import "unsafe"

//go:cgo_import_dynamic libc_Getpgid getpgid "libc.so"
//go:cgo_import_dynamic libc_Getpgrp getpgrp "libc.so"

//go:linkname libc_Getpgid libc_Getpgid
//go:linkname libc_Getpgrp libc_Getpgrp

var (
	libc_Getpgid,
	libc_Getpgrp libcFunc
)