From 565751db4e5b8370c0a05d1998a91e6e20a19bb4 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Wed, 24 Jan 2018 01:59:13 +0100 Subject: remove context --- core.go | 50 ++++++++++++++++++++++++++++---------------------- 1 file changed, 28 insertions(+), 22 deletions(-) (limited to 'core.go') diff --git a/core.go b/core.go index 74355e5..5b08cd9 100644 --- a/core.go +++ b/core.go @@ -2,7 +2,6 @@ package j1 import ( "bytes" - "context" "encoding/binary" "errors" "fmt" @@ -11,6 +10,8 @@ import ( const memSize = 0x4000 +var ErrStop = errors.New("stop") + type Console interface { Read() uint16 Write(uint16) @@ -24,11 +25,10 @@ type Core struct { st0 uint16 // top of data stack d, r stack // data and return stacks tty Console // console i/o - stop context.CancelFunc } -func New() *Core { - return new(Core) +func New(con Console) *Core { + return &Core{tty: con} } // Reset VM @@ -54,20 +54,6 @@ func (c *Core) LoadFile(fname string) error { return c.LoadBytes(data) } -// Run evaluates content of memory -func (c *Core) Run(ctx context.Context, cancel context.CancelFunc, con Console) { - c.stop = cancel - c.tty = con - for { - select { - case <-ctx.Done(): - return - default: - c.Eval(Decode(c.memory[c.pc])) - } - } -} - func (c *Core) String() string { s := fmt.Sprintf("\tPC=%0.4X ST=%0.4X\n", c.pc, c.st0) s += fmt.Sprintf("\tD=%0.4X\n", c.d.dump()) @@ -75,7 +61,7 @@ func (c *Core) String() string { return s } -func (c *Core) writeAt(addr, value uint16) { +func (c *Core) writeAt(addr, value uint16) error { if off := int(addr >> 1); off < memSize { c.memory[addr>>1] = value } @@ -83,8 +69,9 @@ func (c *Core) writeAt(addr, value uint16) { case 0xf000: // key c.tty.Write(value) case 0xf002: // bye - c.stop() + return ErrStop } + return nil } func (c *Core) readAt(addr uint16) uint16 { @@ -100,7 +87,22 @@ func (c *Core) readAt(addr uint16) uint16 { return 0 } -func (c *Core) Eval(ins Instruction) { +// Run evaluates content of memory +func (c *Core) Run() { + for { + ins := c.Decode() + err := c.Eval(ins) + if err != nil { + return + } + } +} + +func (c *Core) Decode() Instruction { + return Decode(c.memory[c.pc]) +} + +func (c *Core) Eval(ins Instruction) error { c.pc++ switch v := ins.(type) { case Lit: @@ -121,7 +123,10 @@ func (c *Core) Eval(ins Instruction) { c.pc = c.r.peek() >> 1 } if v.NtoAtT { - c.writeAt(c.st0, c.d.peek()) + err := c.writeAt(c.st0, c.d.peek()) + if err != nil { + return err + } } st0 := c.newST0(v.Opcode) c.d.move(v.Ddir) @@ -134,6 +139,7 @@ func (c *Core) Eval(ins Instruction) { } c.st0 = st0 } + return nil } var boolValue = map[bool]uint16{ -- cgit v1.2.3