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

package syscall

import (
	"unsafe"
)

var (
	RawSyscallNoError = rawSyscallNoError
	ForceClone3       = &forceClone3
	Prlimit           = prlimit
)

const (
	Sys_GETEUID = sys_GETEUID
)

func Tcgetpgrp(fd int) (pgid int32, err error) {
	_, _, errno := Syscall6(SYS_IOCTL, uintptr(fd), uintptr(TIOCGPGRP), uintptr(unsafe.Pointer(&pgid)), 0, 0, 0)

		origRlimitNofile.Store(&syscall.Rlimit{
			Cur: 1024,
			Max: 65536,
		})
	}

	// Get current process's nofile limit
	var lim syscall.Rlimit
	if err := syscall.Prlimit(0, syscall.RLIMIT_NOFILE, nil, &lim); err != nil {
		t.Fatalf("Failed to get the current nofile limit: %v", err)
	}
	// Set current process's nofile limit through prlimit
	if err := syscall.Prlimit(0, syscall.RLIMIT_NOFILE, &lim, nil); err != nil {

//sys	Munlockall() (err error)

// prlimit changes a resource limit. We use a single definition so that
// we can tell StartProcess to not restore the original NOFILE limit.
//
// golang.org/x/sys linknames prlimit.
// Do not remove or change the type signature.
//
//go:linkname prlimit
func prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
	err = prlimit1(pid, resource, newlimit, old)

          function override_core_limits() {
            while ! pgrep -u istio-proxy envoy; do
              echo "Envoy isn't running yet, trying again..."
              pgrep -u istio-proxy envoy
              sleep .1
            done
            pid="$(pgrep -u istio-proxy envoy)"
            sudo prlimit -p "${pid}" --core=unlimited
          }

	MOVD $·Prctl(SB), R8
	MOVD R8, ret+0(FP)
	RET

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

TEXT ·get_PrlimitAddr(SB), NOSPLIT|NOFRAME, $0-8
	MOVD $·Prlimit(SB), R8
	MOVD R8, ret+0(FP)
	RET

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

TEXT ·get_RenameatAddr(SB), NOSPLIT|NOFRAME, $0-8
	MOVD $·Renameat(SB), R8
	MOVD R8, ret+0(FP)
	RET

//go:linkname syscall_prlimit syscall.prlimit
func syscall_prlimit(pid, resource int, newlimit, old *syscall.Rlimit) error

func Prlimit(pid, resource int, newlimit, old *Rlimit) error {
	// Just call the syscall version, because as of Go 1.21
	// it will affect starting a new process.
	return syscall_prlimit(pid, resource, (*syscall.Rlimit)(newlimit), (*syscall.Rlimit)(old))
}

// After a long discussion on go.dev/issue/46279, we decided the
// best approach was for Go to raise the limit unconditionally for itself,
// and then leave old software to set the limit back as needed.
// Code that really wants Go to leave the limit alone can set the hard limit,
// which Go of course has no choice but to respect.
func init() {
	var lim Rlimit
	if err := Getrlimit(RLIMIT_NOFILE, &lim); err == nil && lim.Cur != lim.Max {

		}
	}

	var maxLimit uint64

	// Set open files limit to maximum.
	if _, maxLimit, err = sys.GetMaxOpenFileLimit(); err != nil {
		return err
	}

	if maxLimit < 4096 && runtime.GOOS != globalWindowsOSName {
		logger.Info("WARNING: maximum file descriptor limit %d is too low for production servers. At least 4096 is recommended. Fix with \"ulimit -n 4096\"",
			maxLimit)
	}

func enter_Prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
	funcref := get_PrlimitAddr()
	if funcptrtest(GetZosLibVec()+SYS_PRLIMIT<<4, "") == 0 {
		*funcref = impl_Prlimit
	} else {
		*funcref = error_Prlimit
	}
	return (*funcref)(pid, resource, newlimit, old)
}

func error_Prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
	err = ENOSYS
	return
}

//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error)
//sys	Prctl(option int, arg2 uintptr, arg3 uintptr, arg4 uintptr, arg5 uintptr) (err error) = SYS___PRCTL_A
//sysnb	Prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT
//sys	Rename(from string, to string) (err error) = SYS___RENAME_A
//sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error) = SYS___RENAMEAT_A