wm/vend/xgb/xgbgen/go_error.go

180 lines
5.4 KiB
Go

package main
import (
"fmt"
)
// Error types
func (e *Error) Define(c *Context) {
c.Putln("// %s is the error number for a %s.", e.ErrConst(), e.ErrConst())
c.Putln("const %s = %d", e.ErrConst(), e.Number)
c.Putln("")
c.Putln("type %s struct {", e.ErrType())
c.Putln("Sequence uint16")
c.Putln("NiceName string")
for _, field := range e.Fields {
field.Define(c)
}
c.Putln("}")
c.Putln("")
// Read defines a function that transforms a byte slice into this
// error struct.
e.Read(c)
// Makes sure this error type implements the xgb.Error interface.
e.ImplementsError(c)
// Let's the XGB event loop read this error.
c.Putln("func init() {")
if c.protocol.isExt() {
c.Putln("xgb.NewExtErrorFuncs[\"%s\"][%d] = %sNew",
c.protocol.ExtXName, e.Number, e.ErrType())
} else {
c.Putln("xgb.NewErrorFuncs[%d] = %sNew", e.Number, e.ErrType())
}
c.Putln("}")
c.Putln("")
}
func (e *Error) Read(c *Context) {
c.Putln("// %sNew constructs a %s value that implements xgb.Error from "+
"a byte slice.", e.ErrType(), e.ErrType())
c.Putln("func %sNew(buf []byte) xgb.Error {", e.ErrType())
c.Putln("v := %s{}", e.ErrType())
c.Putln("v.NiceName = \"%s\"", e.SrcName())
c.Putln("")
c.Putln("b := 1 // skip error determinant")
c.Putln("b += 1 // don't read error number")
c.Putln("")
c.Putln("v.Sequence = xgb.Get16(buf[b:])")
c.Putln("b += 2")
c.Putln("")
for _, field := range e.Fields {
field.Read(c, "v.")
c.Putln("")
}
c.Putln("return v")
c.Putln("}")
c.Putln("")
}
// ImplementsError writes functions to implement the XGB Error interface.
func (e *Error) ImplementsError(c *Context) {
c.Putln("// SequenceId returns the sequence id attached to the %s error.",
e.ErrConst())
c.Putln("// This is mostly used internally.")
c.Putln("func (err %s) SequenceId() uint16 {", e.ErrType())
c.Putln("return err.Sequence")
c.Putln("}")
c.Putln("")
c.Putln("// BadId returns the 'BadValue' number if one exists for the "+
"%s error. If no bad value exists, 0 is returned.", e.ErrConst())
c.Putln("func (err %s) BadId() uint32 {", e.ErrType())
if !c.protocol.isExt() {
c.Putln("return err.BadValue")
} else {
c.Putln("return 0")
}
c.Putln("}")
c.Putln("// Error returns a rudimentary string representation of the %s "+
"error.", e.ErrConst())
c.Putln("")
c.Putln("func (err %s) Error() string {", e.ErrType())
ErrorFieldString(c, e.Fields, e.ErrConst())
c.Putln("}")
c.Putln("")
}
// ErrorCopy types
func (e *ErrorCopy) Define(c *Context) {
c.Putln("// %s is the error number for a %s.", e.ErrConst(), e.ErrConst())
c.Putln("const %s = %d", e.ErrConst(), e.Number)
c.Putln("")
c.Putln("type %s %s", e.ErrType(), e.Old.(*Error).ErrType())
c.Putln("")
// Read defines a function that transforms a byte slice into this
// error struct.
e.Read(c)
// Makes sure this error type implements the xgb.Error interface.
e.ImplementsError(c)
// Let's the XGB know how to read this error.
c.Putln("func init() {")
if c.protocol.isExt() {
c.Putln("xgb.NewExtErrorFuncs[\"%s\"][%d] = %sNew",
c.protocol.ExtXName, e.Number, e.ErrType())
} else {
c.Putln("xgb.NewErrorFuncs[%d] = %sNew", e.Number, e.ErrType())
}
c.Putln("}")
c.Putln("")
}
func (e *ErrorCopy) Read(c *Context) {
c.Putln("// %sNew constructs a %s value that implements xgb.Error from "+
"a byte slice.", e.ErrType(), e.ErrType())
c.Putln("func %sNew(buf []byte) xgb.Error {", e.ErrType())
c.Putln("v := %s(%sNew(buf).(%s))",
e.ErrType(), e.Old.(*Error).ErrType(), e.Old.(*Error).ErrType())
c.Putln("v.NiceName = \"%s\"", e.SrcName())
c.Putln("return v")
c.Putln("}")
c.Putln("")
}
// ImplementsError writes functions to implement the XGB Error interface.
func (e *ErrorCopy) ImplementsError(c *Context) {
c.Putln("// SequenceId returns the sequence id attached to the %s error.",
e.ErrConst())
c.Putln("// This is mostly used internally.")
c.Putln("func (err %s) SequenceId() uint16 {", e.ErrType())
c.Putln("return err.Sequence")
c.Putln("}")
c.Putln("")
c.Putln("// BadId returns the 'BadValue' number if one exists for the "+
"%s error. If no bad value exists, 0 is returned.", e.ErrConst())
c.Putln("func (err %s) BadId() uint32 {", e.ErrType())
if !c.protocol.isExt() {
c.Putln("return err.BadValue")
} else {
c.Putln("return 0")
}
c.Putln("}")
c.Putln("")
c.Putln("// Error returns a rudimentary string representation of the %s "+
"error.", e.ErrConst())
c.Putln("func (err %s) Error() string {", e.ErrType())
ErrorFieldString(c, e.Old.(*Error).Fields, e.ErrConst())
c.Putln("}")
c.Putln("")
}
// ErrorFieldString works for both Error and ErrorCopy. It assembles all of the
// fields in an error and formats them into a single string.
func ErrorFieldString(c *Context, fields []Field, errName string) {
c.Putln("fieldVals := make([]string, 0, %d)", len(fields))
c.Putln("fieldVals = append(fieldVals, \"NiceName: \" + err.NiceName)")
c.Putln("fieldVals = append(fieldVals, "+
"xgb.Sprintf(\"Sequence: %s\", err.Sequence))", "%d")
for _, field := range fields {
switch field.(type) {
case *PadField:
continue
default:
if field.SrcType() == "string" {
c.Putln("fieldVals = append(fieldVals, \"%s: \" + err.%s)",
field.SrcName(), field.SrcName())
} else {
format := fmt.Sprintf("xgb.Sprintf(\"%s: %s\", err.%s)",
field.SrcName(), "%d", field.SrcName())
c.Putln("fieldVals = append(fieldVals, %s)", format)
}
}
}
c.Putln("return \"%s {\" + xgb.StringsJoin(fieldVals, \", \") + \"}\"",
errName)
}