1 files changed, 179 insertions, 0 deletions
diff --git a/nexgb/xgbgen/go_error.go b/nexgb/xgbgen/go_error.go
new file mode 100644
index 0000000..55fd28b
--- /dev/null
+++ b/nexgb/xgbgen/go_error.go
@@ -0,0 +1,179 @@
+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)
+}