Initial QSfera import

Server/vendor/github.com/valyala/fastjson/arena.go

@@ -0,0 +1,126 @@
+package fastjson
+
+import (
+	"strconv"
+)
+
+// Arena may be used for fast creation and re-use of Values.
+//
+// Typical Arena lifecycle:
+//
+//  1. Construct Values via the Arena and Value.Set* calls.
+//  2. Marshal the constructed Values with Value.MarshalTo call.
+//  3. Reset all the constructed Values at once by Arena.Reset call.
+//  4. Go to 1 and re-use the Arena.
+//
+// It is unsafe calling Arena methods from concurrent goroutines.
+// Use per-goroutine Arenas or ArenaPool instead.
+type Arena struct {
+	b []byte
+	c cache
+}
+
+// Reset resets all the Values allocated by a.
+//
+// Values previously allocated by a cannot be used after the Reset call.
+func (a *Arena) Reset() {
+	a.b = a.b[:0]
+	a.c.reset()
+}
+
+// NewObject returns new empty object value.
+//
+// New entries may be added to the returned object via Set call.
+//
+// The returned object is valid until Reset is called on a.
+func (a *Arena) NewObject() *Value {
+	v := a.c.getValue()
+	v.t = TypeObject
+	v.o.reset()
+	return v
+}
+
+// NewArray returns new empty array value.
+//
+// New entries may be added to the returned array via Set* calls.
+//
+// The returned array is valid until Reset is called on a.
+func (a *Arena) NewArray() *Value {
+	v := a.c.getValue()
+	v.t = TypeArray
+	v.a = v.a[:0]
+	return v
+}
+
+// NewString returns new string value containing s.
+//
+// The returned string is valid until Reset is called on a.
+func (a *Arena) NewString(s string) *Value {
+	v := a.c.getValue()
+	v.t = typeRawString
+	bLen := len(a.b)
+	a.b = escapeString(a.b, s)
+	v.s = b2s(a.b[bLen+1 : len(a.b)-1])
+	return v
+}
+
+// NewStringBytes returns new string value containing b.
+//
+// The returned string is valid until Reset is called on a.
+func (a *Arena) NewStringBytes(b []byte) *Value {
+	v := a.c.getValue()
+	v.t = typeRawString
+	bLen := len(a.b)
+	a.b = escapeString(a.b, b2s(b))
+	v.s = b2s(a.b[bLen+1 : len(a.b)-1])
+	return v
+}
+
+// NewNumberFloat64 returns new number value containing f.
+//
+// The returned number is valid until Reset is called on a.
+func (a *Arena) NewNumberFloat64(f float64) *Value {
+	v := a.c.getValue()
+	v.t = TypeNumber
+	bLen := len(a.b)
+	a.b = strconv.AppendFloat(a.b, f, 'g', -1, 64)
+	v.s = b2s(a.b[bLen:])
+	return v
+}
+
+// NewNumberInt returns new number value containing n.
+//
+// The returned number is valid until Reset is called on a.
+func (a *Arena) NewNumberInt(n int) *Value {
+	v := a.c.getValue()
+	v.t = TypeNumber
+	bLen := len(a.b)
+	a.b = strconv.AppendInt(a.b, int64(n), 10)
+	v.s = b2s(a.b[bLen:])
+	return v
+}
+
+// NewNumberString returns new number value containing s.
+//
+// The returned number is valid until Reset is called on a.
+func (a *Arena) NewNumberString(s string) *Value {
+	v := a.c.getValue()
+	v.t = TypeNumber
+	v.s = s
+	return v
+}
+
+// NewNull returns null value.
+func (a *Arena) NewNull() *Value {
+	return valueNull
+}
+
+// NewTrue returns true value.
+func (a *Arena) NewTrue() *Value {
+	return valueTrue
+}
+
+// NewFalse return false value.
+func (a *Arena) NewFalse() *Value {
+	return valueFalse
+}