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// Copyright 2018 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.
package runtime
import "unsafe"
// Call fn with arg as its argument. Return what fn returns.
// fn is the raw pc value of the entry point of the desired function.
// Switches to the system stack, if not already there.
// Preserves the calling point as the location where a profiler traceback will begin.
//go:nosplit
func libcCall(fn, arg unsafe.Pointer) int32 {
// Leave caller's PC/SP/G around for traceback.
gp := getg()
var mp *m
if gp != nil {
mp = gp.m
}
if mp != nil && mp.libcallsp == 0 {
mp.libcallg.set(gp)
mp.libcallpc = getcallerpc()
// sp must be the last, because once async cpu profiler finds
// all three values to be non-zero, it will use them
mp.libcallsp = getcallersp()
} else {
// Make sure we don't reset libcallsp. This makes
// libcCall reentrant; We remember the g/pc/sp for the
// 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
// don't want that call's completion to zero
// libcallsp.
// We don't need to set libcall* while we're in a sighandler
// (even if we're not currently in libc) because we block all
// signals while we're handling a signal. That includes the
// profile signal, which is the one that uses the libcall* info.
mp = nil
}
res := asmcgocall(fn, arg)
if mp != nil {
mp.libcallsp = 0
}
return res
}
// The X versions of syscall expect the libc call to return a 64-bit result.
// Otherwise (the non-X version) expects a 32-bit result.
// This distinction is required because an error is indicated by returning -1,
// and we need to know whether to check 32 or 64 bits of the result.
// (Some libc functions that return 32 bits put junk in the upper 32 bits of AX.)
//go:linkname syscall_syscall syscall.syscall
//go:nosplit
//go:cgo_unsafe_args
func syscall_syscall(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
entersyscallblock()
libcCall(unsafe.Pointer(funcPC(syscall)), unsafe.Pointer(&fn))
exitsyscall()
return
}
func syscall()
//go:linkname syscall_syscall6 syscall.syscall6
//go:nosplit
//go:cgo_unsafe_args
func syscall_syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
entersyscallblock()
libcCall(unsafe.Pointer(funcPC(syscall6)), unsafe.Pointer(&fn))
exitsyscall()
return
}
func syscall6()
//go:linkname syscall_syscall6X syscall.syscall6X
//go:nosplit
//go:cgo_unsafe_args
func syscall_syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
entersyscallblock()
libcCall(unsafe.Pointer(funcPC(syscall6X)), unsafe.Pointer(&fn))
exitsyscall()
return
}
func syscall6X()
//go:linkname syscall_rawSyscall syscall.rawSyscall
//go:nosplit
//go:cgo_unsafe_args
func syscall_rawSyscall(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
libcCall(unsafe.Pointer(funcPC(syscall)), unsafe.Pointer(&fn))
return
}
//go:linkname syscall_rawSyscall6 syscall.rawSyscall6
//go:nosplit
//go:cgo_unsafe_args
func syscall_rawSyscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
libcCall(unsafe.Pointer(funcPC(syscall6)), unsafe.Pointer(&fn))
return
}
// The *_trampoline functions convert from the Go calling convention to the C calling convention
// and then call the underlying libc function. They are defined in sys_darwin_$ARCH.s.
//go:nosplit
//go:cgo_unsafe_args
func pthread_attr_init(attr *pthreadattr) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_attr_init_trampoline)), unsafe.Pointer(&attr))
}
func pthread_attr_init_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_attr_setstacksize(attr *pthreadattr, size uintptr) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_attr_setstacksize_trampoline)), unsafe.Pointer(&attr))
}
func pthread_attr_setstacksize_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_attr_setdetachstate(attr *pthreadattr, state int) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_attr_setdetachstate_trampoline)), unsafe.Pointer(&attr))
}
func pthread_attr_setdetachstate_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_create(attr *pthreadattr, start uintptr, arg unsafe.Pointer) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_create_trampoline)), unsafe.Pointer(&attr))
}
func pthread_create_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func raise(sig uint32) {
libcCall(unsafe.Pointer(funcPC(raise_trampoline)), unsafe.Pointer(&sig))
}
func raise_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_self() (t pthread) {
libcCall(unsafe.Pointer(funcPC(pthread_self_trampoline)), unsafe.Pointer(&t))
return
}
func pthread_self_trampoline()
func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (unsafe.Pointer, int) {
args := struct {
addr unsafe.Pointer
n uintptr
prot, flags, fd int32
off uint32
ret1 unsafe.Pointer
ret2 int
}{addr, n, prot, flags, fd, off, nil, 0}
libcCall(unsafe.Pointer(funcPC(mmap_trampoline)), unsafe.Pointer(&args))
return args.ret1, args.ret2
}
func mmap_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func munmap(addr unsafe.Pointer, n uintptr) {
libcCall(unsafe.Pointer(funcPC(munmap_trampoline)), unsafe.Pointer(&addr))
}
func munmap_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func madvise(addr unsafe.Pointer, n uintptr, flags int32) {
libcCall(unsafe.Pointer(funcPC(madvise_trampoline)), unsafe.Pointer(&addr))
}
func madvise_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func read(fd int32, p unsafe.Pointer, n int32) int32 {
return libcCall(unsafe.Pointer(funcPC(read_trampoline)), unsafe.Pointer(&fd))
}
func read_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func closefd(fd int32) int32 {
return libcCall(unsafe.Pointer(funcPC(close_trampoline)), unsafe.Pointer(&fd))
}
func close_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func exit(code int32) {
libcCall(unsafe.Pointer(funcPC(exit_trampoline)), unsafe.Pointer(&code))
}
func exit_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func usleep(usec uint32) {
libcCall(unsafe.Pointer(funcPC(usleep_trampoline)), unsafe.Pointer(&usec))
}
func usleep_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func write(fd uintptr, p unsafe.Pointer, n int32) int32 {
return libcCall(unsafe.Pointer(funcPC(write_trampoline)), unsafe.Pointer(&fd))
}
func write_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func open(name *byte, mode, perm int32) (ret int32) {
return libcCall(unsafe.Pointer(funcPC(open_trampoline)), unsafe.Pointer(&name))
}
func open_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func nanotime() int64 {
var r struct {
t int64 // raw timer
numer, denom uint32 // conversion factors. nanoseconds = t * numer / denom.
}
libcCall(unsafe.Pointer(funcPC(nanotime_trampoline)), unsafe.Pointer(&r))
// Note: Apple seems unconcerned about overflow here. See
// https://developer.apple.com/library/content/qa/qa1398/_index.html
// Note also, numer == denom == 1 is common.
t := r.t
if r.numer != 1 {
t *= int64(r.numer)
}
if r.denom != 1 {
t /= int64(r.denom)
}
return t
}
func nanotime_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func walltime() (int64, int32) {
var t timeval
libcCall(unsafe.Pointer(funcPC(walltime_trampoline)), unsafe.Pointer(&t))
return int64(t.tv_sec), 1000 * t.tv_usec
}
func walltime_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func sigaction(sig uint32, new *usigactiont, old *usigactiont) {
libcCall(unsafe.Pointer(funcPC(sigaction_trampoline)), unsafe.Pointer(&sig))
}
func sigaction_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func sigprocmask(how uint32, new *sigset, old *sigset) {
libcCall(unsafe.Pointer(funcPC(sigprocmask_trampoline)), unsafe.Pointer(&how))
}
func sigprocmask_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func sigaltstack(new *stackt, old *stackt) {
if new != nil && new.ss_flags&_SS_DISABLE != 0 && new.ss_size == 0 {
// Despite the fact that Darwin's sigaltstack man page says it ignores the size
// when SS_DISABLE is set, it doesn't. sigaltstack returns ENOMEM
// if we don't give it a reasonable size.
// ref: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20140421/214296.html
new.ss_size = 32768
}
libcCall(unsafe.Pointer(funcPC(sigaltstack_trampoline)), unsafe.Pointer(&new))
}
func sigaltstack_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func raiseproc(sig uint32) {
libcCall(unsafe.Pointer(funcPC(raiseproc_trampoline)), unsafe.Pointer(&sig))
}
func raiseproc_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func setitimer(mode int32, new, old *itimerval) {
libcCall(unsafe.Pointer(funcPC(setitimer_trampoline)), unsafe.Pointer(&mode))
}
func setitimer_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func sysctl(mib *uint32, miblen uint32, out *byte, size *uintptr, dst *byte, ndst uintptr) int32 {
return libcCall(unsafe.Pointer(funcPC(sysctl_trampoline)), unsafe.Pointer(&mib))
}
func sysctl_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func fcntl(fd, cmd, arg int32) int32 {
return libcCall(unsafe.Pointer(funcPC(fcntl_trampoline)), unsafe.Pointer(&fd))
}
func fcntl_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func kqueue() int32 {
v := libcCall(unsafe.Pointer(funcPC(kqueue_trampoline)), nil)
return v
}
func kqueue_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32 {
return libcCall(unsafe.Pointer(funcPC(kevent_trampoline)), unsafe.Pointer(&kq))
}
func kevent_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_mutex_init(m *pthreadmutex, attr *pthreadmutexattr) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_mutex_init_trampoline)), unsafe.Pointer(&m))
}
func pthread_mutex_init_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_mutex_lock(m *pthreadmutex) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_mutex_lock_trampoline)), unsafe.Pointer(&m))
}
func pthread_mutex_lock_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_mutex_unlock(m *pthreadmutex) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_mutex_unlock_trampoline)), unsafe.Pointer(&m))
}
func pthread_mutex_unlock_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_cond_init(c *pthreadcond, attr *pthreadcondattr) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_cond_init_trampoline)), unsafe.Pointer(&c))
}
func pthread_cond_init_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_cond_wait(c *pthreadcond, m *pthreadmutex) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_cond_wait_trampoline)), unsafe.Pointer(&c))
}
func pthread_cond_wait_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_cond_timedwait_relative_np(c *pthreadcond, m *pthreadmutex, t *timespec) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_cond_timedwait_relative_np_trampoline)), unsafe.Pointer(&c))
}
func pthread_cond_timedwait_relative_np_trampoline()
//go:nosplit
//go:cgo_unsafe_args
func pthread_cond_signal(c *pthreadcond) int32 {
return libcCall(unsafe.Pointer(funcPC(pthread_cond_signal_trampoline)), unsafe.Pointer(&c))
}
func pthread_cond_signal_trampoline()
// Not used on Darwin, but must be defined.
func exitThread(wait *uint32) {
}
//go:nosplit
func closeonexec(fd int32) {
fcntl(fd, _F_SETFD, _FD_CLOEXEC)
}
// Tell the linker that the libc_* functions are to be found
// in a system library, with the libc_ prefix missing.
//go:cgo_import_dynamic libc_pthread_attr_init pthread_attr_init "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_attr_setstacksize pthread_attr_setstacksize "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_attr_setdetachstate pthread_attr_setdetachstate "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_create pthread_create "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_exit exit "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_raise raise "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_open open "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_close close "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_read read "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_write write "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_mmap mmap "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_munmap munmap "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_madvise madvise "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_error __error "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_usleep usleep "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_mach_timebase_info mach_timebase_info "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_mach_absolute_time mach_absolute_time "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_gettimeofday gettimeofday "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_sigaction sigaction "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_sigmask pthread_sigmask "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_sigaltstack sigaltstack "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_getpid getpid "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_kill kill "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_setitimer setitimer "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_sysctl sysctl "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_fcntl fcntl "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_kqueue kqueue "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_kevent kevent "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_mutex_init pthread_mutex_init "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_mutex_lock pthread_mutex_lock "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_mutex_unlock pthread_mutex_unlock "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_cond_init pthread_cond_init "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_cond_wait pthread_cond_wait "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_cond_timedwait_relative_np pthread_cond_timedwait_relative_np "/usr/lib/libSystem.B.dylib"
//go:cgo_import_dynamic libc_pthread_cond_signal pthread_cond_signal "/usr/lib/libSystem.B.dylib"
// Magic incantation to get libSystem actually dynamically linked.
// TODO: Why does the code require this? See cmd/link/internal/ld/go.go
//go:cgo_import_dynamic _ _ "/usr/lib/libSystem.B.dylib"