arch

type Arch int

type AuxEntry struct {
	Key   uint64
	Value hostarch.Addr
}

type Auxv []AuxEntry

type Context interface {
	// Arch returns the architecture for this Context.
	Arch() Arch

	// Native converts a generic type to a native value.
	//
	// Because the architecture is not specified here, we may be dealing
	// with return values of varying sizes (for example ARCH_GETFS). This
	// is a simple utility function to convert to the native size in these
	// cases, and then we can CopyOut.
	Native(val uintptr) marshal.Marshallable

	// Value converts a native type back to a generic value.
	// Once a value has been converted to native via the above call -- it
	// can be converted back here.
	Value(val marshal.Marshallable) uintptr

	// Width returns the number of bytes for a native value.
	Width() uint

	// Fork creates a clone of the context.
	Fork() Context

	// SyscallNo returns the syscall number.
	SyscallNo() uintptr

	// SyscallSaveOrig save orignal register value.
	SyscallSaveOrig()

	// SyscallArgs returns the syscall arguments in an array.
	SyscallArgs() SyscallArguments

	// Return returns the return value for a system call.
	Return() uintptr

	// SetReturn sets the return value for a system call.
	SetReturn(value uintptr)

	// RestartSyscall reverses over the current syscall instruction, such that
	// when the application resumes execution the syscall will be re-attempted.
	RestartSyscall()

	// RestartSyscallWithRestartBlock reverses over the current syscall
	// instraction and overwrites the current syscall number with that of
	// restart_syscall(2). This causes the application to restart the current
	// syscall with a custom function when execution resumes.
	RestartSyscallWithRestartBlock()

	// IP returns the current instruction pointer.
	IP() uintptr

	// SetIP sets the current instruction pointer.
	SetIP(value uintptr)

	// Stack returns the current stack pointer.
	Stack() uintptr

	// SetStack sets the current stack pointer.
	SetStack(value uintptr)

	// TLS returns the current TLS pointer.
	TLS() uintptr

	// SetTLS sets the current TLS pointer. Returns false if value is invalid.
	SetTLS(value uintptr) bool

	// SetOldRSeqInterruptedIP sets the register that contains the old IP
	// when an "old rseq" restartable sequence is interrupted.
	SetOldRSeqInterruptedIP(value uintptr)

	// StateData returns a pointer to underlying architecture state.
	StateData() *State

	// RegisterMap returns a map of all registers.
	RegisterMap() (map[string]uintptr, error)

	// SignalSetup modifies the context in preparation for handling the
	// given signal.
	//
	// st is the stack where the signal handler frame should be
	// constructed.
	//
	// act is the SigAction that specifies how this signal is being
	// handled.
	//
	// info is the SignalInfo of the signal being delivered.
	//
	// alt is the alternate signal stack (even if the alternate signal
	// stack is not going to be used).
	//
	// sigset is the signal mask before entering the signal handler.
	SignalSetup(st *Stack, act *linux.SigAction, info *linux.SignalInfo, alt *linux.SignalStack, sigset linux.SignalSet) error

	// SignalRestore restores context after returning from a signal
	// handler.
	//
	// st is the current thread stack.
	//
	// rt is true if SignalRestore is being entered from rt_sigreturn and
	// false if SignalRestore is being entered from sigreturn.
	// SignalRestore returns the thread's new signal mask.
	SignalRestore(st *Stack, rt bool) (linux.SignalSet, linux.SignalStack, error)

	// CPUIDEmulate emulates a CPUID instruction according to current register state.
	CPUIDEmulate(l log.Logger)

	// SingleStep returns true if single stepping is enabled.
	SingleStep() bool

	// SetSingleStep enables single stepping.
	SetSingleStep()

	// ClearSingleStep disables single stepping.
	ClearSingleStep()

	// FloatingPointData will be passed to underlying save routines.
	FloatingPointData() *fpu.State

	// NewMmapLayout returns a layout for a new MM, where MinAddr for the
	// returned layout must be no lower than min, and MaxAddr for the returned
	// layout must be no higher than max. Repeated calls to NewMmapLayout may
	// return different layouts.
	NewMmapLayout(min, max hostarch.Addr, limits *limits.LimitSet) (MmapLayout, error)

	// PIELoadAddress returns a preferred load address for a
	// position-independent executable within l.
	PIELoadAddress(l MmapLayout) hostarch.Addr

	// FeatureSet returns the FeatureSet in use in this context.
	FeatureSet() *cpuid.FeatureSet

	// PtracePeekUser implements ptrace(PTRACE_PEEKUSR).
	PtracePeekUser(addr uintptr) (marshal.Marshallable, error)

	// PtracePokeUser implements ptrace(PTRACE_POKEUSR).
	PtracePokeUser(addr, data uintptr) error

	// PtraceGetRegs implements ptrace(PTRACE_GETREGS) by writing the
	// general-purpose registers represented by this Context to dst and
	// returning the number of bytes written.
	PtraceGetRegs(dst io.Writer) (int, error)

	// PtraceSetRegs implements ptrace(PTRACE_SETREGS) by reading
	// general-purpose registers from src into this Context and returning the
	// number of bytes read.
	PtraceSetRegs(src io.Reader) (int, error)

	// PtraceGetRegSet implements ptrace(PTRACE_GETREGSET) by writing the
	// register set given by architecture-defined value regset from this
	// Context to dst and returning the number of bytes written, which must be
	// less than or equal to maxlen.
	PtraceGetRegSet(regset uintptr, dst io.Writer, maxlen int) (int, error)

	// PtraceSetRegSet implements ptrace(PTRACE_SETREGSET) by reading the
	// register set given by architecture-defined value regset from src and
	// returning the number of bytes read, which must be less than or equal to
	// maxlen.
	PtraceSetRegSet(regset uintptr, src io.Reader, maxlen int) (int, error)

	// FullRestore returns 'true' if all CPU registers must be restored
	// when switching to the untrusted application. Typically a task enters
	// and leaves the kernel via a system call. Platform.Switch() may
	// optimize for this by not saving/restoring all registers if allowed
	// by the ABI. For e.g. the amd64 ABI specifies that syscall clobbers
	// %rcx and %r11. If FullRestore returns true then these optimizations
	// must be disabled and all registers restored.
	FullRestore() bool
}

type MmapDirection int

type MmapLayout struct {
	// MinAddr is the lowest mappable address.
	MinAddr hostarch.Addr

	// MaxAddr is the highest mappable address.
	MaxAddr hostarch.Addr

	// BottomUpBase is the lowest address that may be returned for a
	// MmapBottomUp mmap.
	BottomUpBase hostarch.Addr

	// TopDownBase is the highest address that may be returned for a
	// MmapTopDown mmap.
	TopDownBase hostarch.Addr

	// DefaultDirection is the direction for most non-fixed mmaps in this
	// layout.
	DefaultDirection MmapDirection

	// MaxStackRand is the maximum randomization to apply to stack
	// allocations to maintain a proper gap between the stack and
	// TopDownBase.
	MaxStackRand uint64
}

type Registers struct {
	linux.PtraceRegs
}

type SignalContext64 struct {
	R8      uint64
	R9      uint64
	R10     uint64
	R11     uint64
	R12     uint64
	R13     uint64
	R14     uint64
	R15     uint64
	Rdi     uint64
	Rsi     uint64
	Rbp     uint64
	Rbx     uint64
	Rdx     uint64
	Rax     uint64
	Rcx     uint64
	Rsp     uint64
	Rip     uint64
	Eflags  uint64
	Cs      uint16
	Gs      uint16 // always 0 on amd64.
	Fs      uint16 // always 0 on amd64.
	Ss      uint16 // only restored if _UC_STRICT_RESTORE_SS (unsupported).
	Err     uint64
	Trapno  uint64
	Oldmask linux.SignalSet
	Cr2     uint64
	// Pointer to a struct _fpstate. See b/33003106#comment8.
	Fpstate  uint64
	Reserved [8]uint64
}

type Stack struct {
	// Our arch info.
	// We use this for automatic Native conversion of hostarch.Addrs during
	// Push() and Pop().
	Arch Context

	// The interface used to actually copy user memory.
	IO usermem.IO

	// Our current stack bottom.
	Bottom hostarch.Addr
	// contains filtered or unexported fields
}

type StackLayout struct {
	// ArgvStart is the beginning of the argument vector.
	ArgvStart hostarch.Addr

	// ArgvEnd is the end of the argument vector.
	ArgvEnd hostarch.Addr

	// EnvvStart is the beginning of the environment vector.
	EnvvStart hostarch.Addr

	// EnvvEnd is the end of the environment vector.
	EnvvEnd hostarch.Addr
}

type State struct {
	// The system registers.
	Regs Registers

	// FeatureSet is a pointer to the currently active feature set.
	FeatureSet *cpuid.FeatureSet
	// contains filtered or unexported fields
}

type SyscallArgument struct {
	// Prefer to use accessor methods instead of 'Value' directly.
	Value uintptr
}

type SyscallArguments [6]SyscallArgument

type UContext64 struct {
	Flags    uint64
	Link     uint64
	Stack    linux.SignalStack
	MContext SignalContext64
	Sigset   linux.SignalSet
}