go-json/encode.go

303 lines
8.2 KiB
Go

package json
import (
"io"
"unsafe"
"github.com/goccy/go-json/internal/encoder"
"github.com/goccy/go-json/internal/encoder/vm"
"github.com/goccy/go-json/internal/encoder/vm_escaped"
"github.com/goccy/go-json/internal/encoder/vm_escaped_indent"
"github.com/goccy/go-json/internal/encoder/vm_indent"
)
// An Encoder writes JSON values to an output stream.
type Encoder struct {
w io.Writer
enabledIndent bool
enabledHTMLEscape bool
prefix string
indentStr string
}
type EncodeOption int
const (
EncodeOptionHTMLEscape EncodeOption = 1 << iota
EncodeOptionIndent
EncodeOptionUnorderedMap
EncodeOptionDebug
)
// NewEncoder returns a new encoder that writes to w.
func NewEncoder(w io.Writer) *Encoder {
return &Encoder{w: w, enabledHTMLEscape: true}
}
// Encode writes the JSON encoding of v to the stream, followed by a newline character.
//
// See the documentation for Marshal for details about the conversion of Go values to JSON.
func (e *Encoder) Encode(v interface{}) error {
return e.EncodeWithOption(v)
}
// EncodeWithOption call Encode with EncodeOption.
func (e *Encoder) EncodeWithOption(v interface{}, optFuncs ...EncodeOptionFunc) error {
ctx := encoder.TakeRuntimeContext()
err := e.encodeWithOption(ctx, v, optFuncs...)
encoder.ReleaseRuntimeContext(ctx)
return err
}
func (e *Encoder) encodeWithOption(ctx *encoder.RuntimeContext, v interface{}, optFuncs ...EncodeOptionFunc) error {
var opt EncodeOption
if e.enabledHTMLEscape {
opt |= EncodeOptionHTMLEscape
}
for _, optFunc := range optFuncs {
opt = optFunc(opt)
}
var (
buf []byte
err error
)
if e.enabledIndent {
buf, err = encodeIndent(ctx, v, e.prefix, e.indentStr, opt)
} else {
buf, err = encode(ctx, v, opt)
}
if err != nil {
return err
}
if e.enabledIndent {
buf = buf[:len(buf)-2]
} else {
buf = buf[:len(buf)-1]
}
buf = append(buf, '\n')
if _, err := e.w.Write(buf); err != nil {
return err
}
return nil
}
// SetEscapeHTML specifies whether problematic HTML characters should be escaped inside JSON quoted strings.
// The default behavior is to escape &, <, and > to \u0026, \u003c, and \u003e to avoid certain safety problems that can arise when embedding JSON in HTML.
//
// In non-HTML settings where the escaping interferes with the readability of the output, SetEscapeHTML(false) disables this behavior.
func (e *Encoder) SetEscapeHTML(on bool) {
e.enabledHTMLEscape = on
}
// SetIndent instructs the encoder to format each subsequent encoded value as if indented by the package-level function Indent(dst, src, prefix, indent).
// Calling SetIndent("", "") disables indentation.
func (e *Encoder) SetIndent(prefix, indent string) {
if prefix == "" && indent == "" {
e.enabledIndent = false
return
}
e.prefix = prefix
e.indentStr = indent
e.enabledIndent = true
}
func marshal(v interface{}, opt EncodeOption) ([]byte, error) {
ctx := encoder.TakeRuntimeContext()
buf, err := encode(ctx, v, opt|EncodeOptionHTMLEscape)
if err != nil {
encoder.ReleaseRuntimeContext(ctx)
return nil, err
}
// this line exists to escape call of `runtime.makeslicecopy` .
// if use `make([]byte, len(buf)-1)` and `copy(copied, buf)`,
// dst buffer size and src buffer size are differrent.
// in this case, compiler uses `runtime.makeslicecopy`, but it is slow.
buf = buf[:len(buf)-1]
copied := make([]byte, len(buf))
copy(copied, buf)
encoder.ReleaseRuntimeContext(ctx)
return copied, nil
}
func marshalNoEscape(v interface{}, opt EncodeOption) ([]byte, error) {
ctx := encoder.TakeRuntimeContext()
buf, err := encodeNoEscape(ctx, v, opt|EncodeOptionHTMLEscape)
if err != nil {
encoder.ReleaseRuntimeContext(ctx)
return nil, err
}
// this line exists to escape call of `runtime.makeslicecopy` .
// if use `make([]byte, len(buf)-1)` and `copy(copied, buf)`,
// dst buffer size and src buffer size are differrent.
// in this case, compiler uses `runtime.makeslicecopy`, but it is slow.
buf = buf[:len(buf)-1]
copied := make([]byte, len(buf))
copy(copied, buf)
encoder.ReleaseRuntimeContext(ctx)
return copied, nil
}
func marshalIndent(v interface{}, prefix, indent string, opt EncodeOption) ([]byte, error) {
ctx := encoder.TakeRuntimeContext()
buf, err := encodeIndent(ctx, v, prefix, indent, opt|EncodeOptionHTMLEscape)
if err != nil {
encoder.ReleaseRuntimeContext(ctx)
return nil, err
}
buf = buf[:len(buf)-2]
copied := make([]byte, len(buf))
copy(copied, buf)
encoder.ReleaseRuntimeContext(ctx)
return copied, nil
}
func encode(ctx *encoder.RuntimeContext, v interface{}, opt EncodeOption) ([]byte, error) {
b := ctx.Buf[:0]
if v == nil {
b = encoder.AppendNull(b)
b = encoder.AppendComma(b)
return b, nil
}
header := (*emptyInterface)(unsafe.Pointer(&v))
typ := header.typ
typeptr := uintptr(unsafe.Pointer(typ))
codeSet, err := encoder.CompileToGetCodeSet(typeptr)
if err != nil {
return nil, err
}
p := uintptr(header.ptr)
var code *encoder.Opcode
if (opt & EncodeOptionHTMLEscape) != 0 {
code = codeSet.EscapeKeyCode
} else {
code = codeSet.NoescapeKeyCode
}
ctx.Init(code, p, codeSet.CodeLength)
ctx.KeepRefs = append(ctx.KeepRefs, header.ptr)
buf, err := encodeRunCode(ctx, b, codeSet, opt)
if err != nil {
return nil, err
}
ctx.Buf = buf
return buf, nil
}
func encodeNoEscape(ctx *encoder.RuntimeContext, v interface{}, opt EncodeOption) ([]byte, error) {
b := ctx.Buf[:0]
if v == nil {
b = encoder.AppendNull(b)
b = encoder.AppendComma(b)
return b, nil
}
header := (*emptyInterface)(unsafe.Pointer(&v))
typ := header.typ
typeptr := uintptr(unsafe.Pointer(typ))
codeSet, err := encoder.CompileToGetCodeSet(typeptr)
if err != nil {
return nil, err
}
var code *encoder.Opcode
if (opt & EncodeOptionHTMLEscape) != 0 {
code = codeSet.EscapeKeyCode
} else {
code = codeSet.NoescapeKeyCode
}
p := uintptr(header.ptr)
ctx.Init(code, p, codeSet.CodeLength)
buf, err := encodeRunCode(ctx, b, codeSet, opt)
if err != nil {
return nil, err
}
ctx.Buf = buf
return buf, nil
}
func encodeIndent(ctx *encoder.RuntimeContext, v interface{}, prefix, indent string, opt EncodeOption) ([]byte, error) {
b := ctx.Buf[:0]
if v == nil {
b = encoder.AppendNull(b)
b = encoder.AppendCommaIndent(b)
return b, nil
}
header := (*emptyInterface)(unsafe.Pointer(&v))
typ := header.typ
typeptr := uintptr(unsafe.Pointer(typ))
codeSet, err := encoder.CompileToGetCodeSet(typeptr)
if err != nil {
return nil, err
}
var code *encoder.Opcode
if (opt & EncodeOptionHTMLEscape) != 0 {
code = codeSet.EscapeKeyCode
} else {
code = codeSet.NoescapeKeyCode
}
p := uintptr(header.ptr)
ctx.Init(code, p, codeSet.CodeLength)
buf, err := encodeRunIndentCode(ctx, b, codeSet, prefix, indent, opt)
ctx.KeepRefs = append(ctx.KeepRefs, header.ptr)
if err != nil {
return nil, err
}
ctx.Buf = buf
return buf, nil
}
func encodeRunCode(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet, opt EncodeOption) ([]byte, error) {
if (opt & EncodeOptionDebug) != 0 {
return encodeDebugRunCode(ctx, b, codeSet, opt)
}
if (opt & EncodeOptionHTMLEscape) != 0 {
return vm_escaped.Run(ctx, b, codeSet, encoder.Option(opt))
}
return vm.Run(ctx, b, codeSet, encoder.Option(opt))
}
func encodeDebugRunCode(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet, opt EncodeOption) ([]byte, error) {
if (opt & EncodeOptionHTMLEscape) != 0 {
return vm_escaped.DebugRun(ctx, b, codeSet, encoder.Option(opt))
}
return vm.DebugRun(ctx, b, codeSet, encoder.Option(opt))
}
func encodeRunIndentCode(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet, prefix, indent string, opt EncodeOption) ([]byte, error) {
ctx.Prefix = []byte(prefix)
ctx.IndentStr = []byte(indent)
if (opt & EncodeOptionDebug) != 0 {
return encodeDebugRunIndentCode(ctx, b, codeSet, opt)
}
if (opt & EncodeOptionHTMLEscape) != 0 {
return vm_escaped_indent.Run(ctx, b, codeSet, encoder.Option(opt))
}
return vm_indent.Run(ctx, b, codeSet, encoder.Option(opt))
}
func encodeDebugRunIndentCode(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet, opt EncodeOption) ([]byte, error) {
if (opt & EncodeOptionHTMLEscape) != 0 {
return vm_escaped_indent.DebugRun(ctx, b, codeSet, encoder.Option(opt))
}
return vm_indent.DebugRun(ctx, b, codeSet, encoder.Option(opt))
}