unions, events and errors... oh my

This commit is contained in:
Andrew Gallant (Ocelot) 2012-05-01 01:08:03 -04:00
parent 73154769b3
commit 83a71d4648
8 changed files with 317 additions and 38 deletions

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@ -9,6 +9,7 @@ type Field interface {
Initialize(p *Protocol)
SrcName() string
XmlName() string
SrcType() string
Size() Size
Define(c *Context)
@ -30,6 +31,10 @@ func (p *PadField) XmlName() string {
panic("illegal to take XML name of a pad field")
}
func (f *PadField) SrcType() string {
panic("it is illegal to call SrcType on a SwitchField field")
}
func (p *PadField) Size() Size {
return newFixedSize(p.Bytes)
}
@ -53,6 +58,10 @@ func (f *SingleField) XmlName() string {
return f.xmlName
}
func (f *SingleField) SrcType() string {
return f.Type.SrcName()
}
func (f *SingleField) Size() Size {
return f.Type.Size()
}
@ -72,9 +81,9 @@ func (f *ListField) XmlName() string {
return f.xmlName
}
// func (f *ListField) Size() Size {
// return newExpressionSize(f.LengthExpr).Multiply(f.Type.Size())
// }
func (f *ListField) SrcType() string {
return fmt.Sprintf("[]%s", f.Type.SrcName())
}
func (f *ListField) Size() Size {
simpleLen := &Function{
@ -126,6 +135,10 @@ func (f *ExprField) XmlName() string {
return f.xmlName
}
func (f *ExprField) SrcType() string {
return f.Type.SrcName()
}
func (f *ExprField) Size() Size {
return f.Type.Size()
}
@ -150,6 +163,10 @@ func (f *ValueField) XmlName() string {
panic("it is illegal to call XmlName on a ValueField field")
}
func (f *ValueField) SrcType() string {
return f.MaskType.SrcName()
}
func (f *ValueField) Size() Size {
return f.MaskType.Size()
}
@ -174,6 +191,10 @@ func (f *SwitchField) XmlName() string {
panic("it is illegal to call XmlName on a SwitchField field")
}
func (f *SwitchField) SrcType() string {
panic("it is illegal to call SrcType on a SwitchField field")
}
// XXX: This is a bit tricky. The size has to be represented as a non-concrete
// expression that finds *which* bitcase fields are included, and sums the
// sizes of those fields.

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@ -22,18 +22,36 @@ func (e *ErrorCopy) Define(c *Context) {
c.Putln("")
c.Putln("type %s %s", e.ErrType(), e.Old.(*Error).ErrType())
c.Putln("")
c.Putln("func New%s(buf []byte) %s {", e.SrcName(), e.ErrType())
c.Putln("return (%s)(New%s(buf))", e.ErrType(), e.Old.SrcName())
c.Putln("}")
c.Putln("")
// Read defines a function that transforms a byte slice into this
// error struct.
e.Read(c)
// Write defines a function that transoforms this error struct into
// a byte slice.
e.Write(c)
// Makes sure that this error type is an Error interface.
c.Putln("func (err %s) ImplementsError() { }", e.ErrType())
c.Putln("")
c.Putln("func (err %s) Bytes() []byte {", e.ErrType())
c.Putln("return (%s)(err).Bytes()", e.Old.(*Error).ErrType())
c.Putln("}")
c.Putln("")
// Let's the XGB know how to read this error.
c.Putln("func init() {")
c.Putln("newErrorFuncs[%d] = New%s", e.Number, e.SrcName())
c.Putln("}")
c.Putln("")
}
func (e *ErrorCopy) Read(c *Context) {
c.Putln("func New%s(buf []byte) %s {", e.SrcName(), e.ErrType())
c.Putln("return (%s)(New%s(buf))", e.ErrType(), e.Old.SrcName())
c.Putln("}")
c.Putln("")
}
func (e *ErrorCopy) Write(c *Context) {
c.Putln("func (err %s) Bytes() []byte {", e.ErrType())
c.Putln("return (%s)(err).Bytes()", e.Old.(*Error).ErrType())
c.Putln("}")
c.Putln("")
}

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@ -3,14 +3,75 @@ package main
// Event types
func (e *Event) Define(c *Context) {
c.Putln("// Event definition %s (%d)", e.SrcName(), e.Number)
c.Putln("// Size: %s", e.Size())
c.Putln("type %s struct {", e.EvType())
c.Putln("Sequence uint16")
for _, field := range e.Fields {
field.Define(c)
}
c.Putln("}")
c.Putln("")
// Read defines a function that transforms a byte slice into this
// event struct.
e.Read(c)
// Write defines a function that transoforms this event struct into
// a byte slice.
e.Write(c)
// Makes sure that this event type is an Event interface.
c.Putln("func (v %s) ImplementsEvent() { }", e.EvType())
c.Putln("")
// Let's the XGB event loop read this event.
c.Putln("func init() {")
c.Putln("newEventFuncs[%d] = New%s", e.Number, e.SrcName())
c.Putln("}")
c.Putln("")
}
func (e *Event) Read(c *Context, prefix string) {
func (e *Event) Read(c *Context) {
c.Putln("// Event read %s", e.SrcName())
c.Putln("func New%s(buf []byte) %s {", e.SrcName(), e.EvType())
c.Putln("v := %s{}", e.EvType())
c.Putln("b := 1 // don't read event number")
c.Putln("")
for i, field := range e.Fields {
if i == 1 && !e.NoSequence {
c.Putln("v.Sequence = get16(buf[b:])")
c.Putln("b += 2")
c.Putln("")
}
field.Read(c)
c.Putln("")
}
c.Putln("return v")
c.Putln("}")
c.Putln("")
}
func (e *Event) Write(c *Context, prefix string) {
func (e *Event) Write(c *Context) {
c.Putln("// Event write %s", e.SrcName())
c.Putln("func (v %s) Bytes() []byte {", e.EvType())
c.Putln("buf := make([]byte, %s)", e.Size())
c.Putln("b := 0")
c.Putln("")
c.Putln("// write event number")
c.Putln("buf[b] = %d", e.Number)
c.Putln("b += 1")
c.Putln("")
for i, field := range e.Fields {
if i == 1 && !e.NoSequence {
c.Putln("b += 2 // skip sequence number")
c.Putln("")
}
field.Write(c)
c.Putln("")
}
c.Putln("return buf")
c.Putln("}")
c.Putln("")
}
// EventCopy types
@ -21,18 +82,36 @@ func (e *EventCopy) Define(c *Context) {
c.Putln("")
c.Putln("type %s %s", e.EvType(), e.Old.(*Event).EvType())
c.Putln("")
c.Putln("func New%s(buf []byte) %s {", e.SrcName(), e.EvType())
c.Putln("return (%s)(New%s(buf))", e.EvType(), e.Old.SrcName())
c.Putln("}")
c.Putln("")
c.Putln("func (ev %s) ImplementsEvent() { }", e.EvType())
c.Putln("")
c.Putln("func (ev %s) Bytes() []byte {", e.EvType())
c.Putln("return (%s)(ev).Bytes()", e.Old.(*Event).EvType())
c.Putln("}")
// Read defines a function that transforms a byte slice into this
// event struct.
e.Read(c)
// Write defines a function that transoforms this event struct into
// a byte slice.
e.Write(c)
// Makes sure that this event type is an Event interface.
c.Putln("func (v %s) ImplementsEvent() { }", e.EvType())
c.Putln("")
// Let's the XGB event loop read this event.
c.Putln("func init() {")
c.Putln("newEventFuncs[%d] = New%s", e.Number, e.SrcName())
c.Putln("}")
c.Putln("")
}
func (e *EventCopy) Read(c *Context) {
c.Putln("func New%s(buf []byte) %s {", e.SrcName(), e.EvType())
c.Putln("return (%s)(New%s(buf))", e.EvType(), e.Old.SrcName())
c.Putln("}")
c.Putln("")
}
func (e *EventCopy) Write(c *Context) {
c.Putln("func (v %s) Bytes() []byte {", e.EvType())
c.Putln("return (%s)(ev).Bytes()", e.Old.(*Event).EvType())
c.Putln("}")
c.Putln("")
}

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@ -12,8 +12,6 @@ func (f *ListField) Define(c *Context) {
}
func (f *ListField) Read(c *Context) {
c.Putln("")
switch t := f.Type.(type) {
case *Resource:
length := f.LengthExpr.Reduce("v.", "")
@ -34,6 +32,10 @@ func (f *ListField) Read(c *Context) {
c.Putln("}")
c.Putln("b = pad(b)")
}
case *Union:
c.Putln("v.%s = make([]%s, %s)",
f.SrcName(), t.SrcName(), f.LengthExpr.Reduce("v.", ""))
c.Putln("b += Read%sList(buf[b:], v.%s)", t.SrcName(), f.SrcName())
case *Struct:
c.Putln("v.%s = make([]%s, %s)",
f.SrcName(), t.SrcName(), f.LengthExpr.Reduce("v.", ""))
@ -45,8 +47,6 @@ func (f *ListField) Read(c *Context) {
}
func (f *ListField) Write(c *Context) {
c.Putln("")
switch t := f.Type.(type) {
case *Resource:
length := f.LengthExpr.Reduce("v.", "")
@ -65,6 +65,8 @@ func (f *ListField) Write(c *Context) {
c.Putln("}")
c.Putln("b = pad(b)")
}
case *Union:
c.Putln("b += %sListBytes(buf[b:], v.%s)", t.SrcName(), f.SrcName())
case *Struct:
c.Putln("b += %sListBytes(buf[b:], v.%s)", t.SrcName(), f.SrcName())
default:

View File

@ -25,6 +25,16 @@ func ReadSimpleSingleField(c *Context, name string, typ Type) {
c.Putln("%s = %s(get64(buf[b:]))", name, t.SrcName())
}
case *Base:
// If this is a bool, stop short and do something special.
if t.SrcName() == "bool" {
c.Putln("if buf[b] == 1 {")
c.Putln("%s = true", name)
c.Putln("} else {")
c.Putln("%s = false", name)
c.Putln("}")
break
}
var val string
switch t.Size().Eval() {
case 1:
@ -44,7 +54,7 @@ func ReadSimpleSingleField(c *Context, name string, typ Type) {
}
c.Putln("%s = %s", name, val)
default:
log.Fatalf("Cannot read field '%s' as a simple field with %T type.",
log.Panicf("Cannot read field '%s' as a simple field with %T type.",
name, typ)
}
@ -62,9 +72,11 @@ func (f *SingleField) Read(c *Context) {
case *Struct:
c.Putln("v.%s = %s{}", f.SrcName(), t.SrcName())
c.Putln("b += Read%s(buf[b:], &v.%s)", t.SrcName(), f.SrcName())
c.Putln("")
case *Union:
c.Putln("v.%s = %s{}", f.SrcName(), t.SrcName())
c.Putln("b += Read%s(buf[b:], &v.%s)", t.SrcName(), f.SrcName())
default:
log.Fatalf("Cannot read field '%s' with %T type.", f.XmlName(), f.Type)
log.Panicf("Cannot read field '%s' with %T type.", f.XmlName(), f.Type)
}
}
@ -84,6 +96,16 @@ func WriteSimpleSingleField(c *Context, name string, typ Type) {
c.Putln("put64(buf[b:], uint64(%s))", name)
}
case *Base:
// If this is a bool, stop short and do something special.
if t.SrcName() == "bool" {
c.Putln("if %s {", name)
c.Putln("buf[b] = 1")
c.Putln("} else {")
c.Putln("buf[b] = 0")
c.Putln("}")
break
}
switch t.Size().Eval() {
case 1:
if t.SrcName() != "byte" {
@ -126,11 +148,17 @@ func (f *SingleField) Write(c *Context) {
ReadSimpleSingleField(c, fmt.Sprintf("v.%s", f.SrcName()), t)
case *Base:
ReadSimpleSingleField(c, fmt.Sprintf("v.%s", f.SrcName()), t)
case *Union:
c.Putln("{")
c.Putln("unionBytes := v.%s.Bytes()", f.SrcName())
c.Putln("copy(buf[b:], unionBytes)")
c.Putln("b += pad(len(unionBytes))")
c.Putln("}")
case *Struct:
c.Putln("{")
c.Putln("structBytes := v.%s.Bytes()", f.SrcName())
c.Putln("copy(buf[b:], structBytes)")
c.Putln("b += len(structBytes)")
c.Putln("b += pad(len(structBytes))")
c.Putln("}")
default:
log.Fatalf("Cannot read field '%s' with %T type.", f.XmlName(), f.Type)

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@ -13,7 +13,7 @@ func (s *Struct) Define(c *Context) {
// Write function that reads bytes and produces this struct.
s.Read(c)
// Write function that reads a list of this structs.
// Write function that reads bytes and produces a list of this struct.
s.ReadList(c)
// Write function that writes bytes given this struct.
@ -68,7 +68,7 @@ func (s *Struct) ReadList(c *Context) {
func (s *Struct) Write(c *Context) {
c.Putln("// Struct write %s", s.SrcName())
c.Putln("func (v %s) Bytes() []byte {", s.SrcName())
c.Putln("buf := make([]byte, %s)", s.Size().Reduce("s.", ""))
c.Putln("buf := make([]byte, %s)", s.Size().Reduce("v.", ""))
c.Putln("b := 0")
c.Putln("")
for _, field := range s.Fields {
@ -88,10 +88,11 @@ func (s *Struct) WriteList(c *Context) {
c.Putln("for _, item := range list {")
c.Putln("structBytes = item.Bytes()")
c.Putln("copy(buf[b:], len(structBytes))")
c.Putln("b += len(structBytes)")
c.Putln("b += pad(len(structBytes))")
c.Putln("}")
c.Putln("return b")
c.Putln("}")
c.Putln("")
}
func (s *Struct) WriteListSize(c *Context) {
@ -101,7 +102,7 @@ func (s *Struct) WriteListSize(c *Context) {
c.Putln("for _, item := range list {")
c.Putln("size += %s", s.Size().Reduce("item.", ""))
c.Putln("}")
c.Putln("return pad(size)")
c.Putln("return size")
c.Putln("}")
c.Putln("")
}

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@ -3,13 +3,143 @@ package main
// Union types
func (u *Union) Define(c *Context) {
c.Putln("// Union definition %s", u.SrcName())
c.Putln("// Note that to *create* a Union, you should *never* create")
c.Putln("// this struct directly (unless you know what you're doing).")
c.Putln("// Instead use one of the following constructors for '%s':",
u.SrcName())
for _, field := range u.Fields {
c.Putln("// New%s%s(%s %s) %s", u.SrcName(), field.SrcName(),
field.SrcName(), field.SrcType(), u.SrcName())
}
c.Putln("type %s struct {", u.SrcName())
for _, field := range u.Fields {
field.Define(c)
}
c.Putln("}")
c.Putln("")
// Write functions for each field that create instances of this
// union using the corresponding field.
u.New(c)
// Write function that reads bytes and produces this union.
u.Read(c)
// Write function that reads bytes and produces a list of this union.
u.ReadList(c)
// Write function that writes bytes given this union.
u.Write(c)
// Write function that writes a list of this union.
u.WriteList(c)
// Write function that computes the size of a list of these unions.
u.WriteListSize(c)
}
func (u *Union) Read(c *Context, prefix string) {
func (u *Union) New(c *Context) {
for _, field := range u.Fields {
c.Putln("// Union constructor for %s for field %s.",
u.SrcName(), field.SrcName())
c.Putln("func New%s%s(%s %s) %s {",
u.SrcName(), field.SrcName(), field.SrcName(),
field.SrcType(), u.SrcName())
c.Putln("var b int")
c.Putln("buf := make([]byte, %s)", u.Size())
c.Putln("")
field.Write(c)
c.Putln("")
c.Putln("// Create the Union type")
c.Putln("v := %s{}", u.SrcName())
c.Putln("")
c.Putln("// Now copy buf into all fields")
c.Putln("")
for _, field2 := range u.Fields {
c.Putln("b = 0 // always read the same bytes")
field2.Read(c)
c.Putln("")
}
c.Putln("return v")
c.Putln("}")
c.Putln("")
}
}
func (u *Union) Read(c *Context) {
c.Putln("// Union read %s", u.SrcName())
c.Putln("func Read%s(buf []byte, v *%s) int {", u.SrcName(), u.SrcName())
c.Putln("var b int")
c.Putln("")
for _, field := range u.Fields {
c.Putln("b = 0 // re-read the same bytes")
field.Read(c)
c.Putln("")
}
c.Putln("return %s", u.Size())
c.Putln("}")
c.Putln("")
}
func (u *Union) Write(c *Context, prefix string) {
func (u *Union) ReadList(c *Context) {
c.Putln("// Union list read %s", u.SrcName())
c.Putln("func Read%sList(buf []byte, dest []%s) int {",
u.SrcName(), u.SrcName())
c.Putln("b := 0")
c.Putln("for i := 0; i < len(dest); i++ {")
c.Putln("dest[i] = %s{}", u.SrcName())
c.Putln("b += Read%s(buf[b:], &dest[i])", u.SrcName())
c.Putln("}")
c.Putln("return pad(b)")
c.Putln("}")
c.Putln("")
}
// This is a bit tricky since writing from a Union implies that only
// the data inside ONE of the elements is actually written.
// However, we only currently support unions where every field has the
// *same* *fixed* size. Thus, we make sure to always read bytes into
// every field which allows us to simply pick the first field and write it.
func (u *Union) Write(c *Context) {
c.Putln("// Union write %s", u.SrcName())
c.Putln("// Each field in a union must contain the same data.")
c.Putln("// So simply pick the first field and write that to the wire.")
c.Putln("func (v %s) Bytes() []byte {", u.SrcName())
c.Putln("buf := make([]byte, %s)", u.Size().Reduce("v.", ""))
c.Putln("b := 0")
c.Putln("")
u.Fields[0].Write(c)
c.Putln("return buf")
c.Putln("}")
c.Putln("")
}
func (u *Union) WriteList(c *Context) {
c.Putln("// Union list write %s", u.SrcName())
c.Putln("func %sListBytes(buf []byte, list []%s) int {",
u.SrcName(), u.SrcName())
c.Putln("b := 0")
c.Putln("var unionBytes []byte")
c.Putln("for _, item := range list {")
c.Putln("unionBytes = item.Bytes()")
c.Putln("copy(buf[b:], len(unionBytes))")
c.Putln("b += pad(len(unionBytes))")
c.Putln("}")
c.Putln("return b")
c.Putln("}")
c.Putln("")
}
func (u *Union) WriteListSize(c *Context) {
c.Putln("// Union list size %s", u.SrcName())
c.Putln("func %sListSize(list []%s) int {", u.SrcName(), u.SrcName())
c.Putln("size := 0")
c.Putln("for _, item := range list {")
c.Putln("size += %s", u.Size().Reduce("item.", ""))
c.Putln("}")
c.Putln("return size")
c.Putln("}")
c.Putln("")
}

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@ -191,7 +191,7 @@ func (e *Event) XmlName() string {
}
func (e *Event) Size() Size {
panic("Cannot take size of Event type.")
return newExpressionSize(&Value{v: 32})
}
func (e *Event) Initialize(p *Protocol) {
@ -358,7 +358,7 @@ func (u *Union) Size() Size {
}
func (u *Union) Initialize(p *Protocol) {
u.srcName = TypeSrcName(p, u)
u.srcName = fmt.Sprintf("%sUnion", TypeSrcName(p, u))
for _, field := range u.Fields {
field.Initialize(p)
}