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Diffstat (limited to 'walk/read.go')
-rw-r--r--walk/read.go452
1 files changed, 316 insertions, 136 deletions
diff --git a/walk/read.go b/walk/read.go
index 6f3acfe..58dfcae 100644
--- a/walk/read.go
+++ b/walk/read.go
@@ -5,13 +5,41 @@ import (
"math"
"strings"
"strconv"
+ "fmt"
)
+type ReadAction interface {
+ String() string
+}
+
+type ActionReadValue struct {}
+func (_ ActionReadValue) String() string {
+ return "read"
+}
+
+type ActionAppendPath struct {
+ atoms []Atom
+}
+func (action ActionAppendPath) String() string {
+ return fmt.Sprintf("append(%v)", action.atoms)
+}
+
+type ActionPopPath struct {}
+func (_ ActionPopPath) String() string {
+ return "pop"
+}
+
+type ActionIncrementPath struct {}
+func (_ ActionIncrementPath) String() string {
+ return "increment"
+}
+
type JSONInStructure int
const (
JSONInRoot JSONInStructure = iota
JSONInMap
JSONInArray
+ JSONInString
JSONInValueEnd
)
@@ -19,6 +47,11 @@ type JSONIn struct {
path []Atom
reader *bufio.Reader
structure []JSONInStructure
+ readBuffer []Atom
+ readIndex int
+ readBufferCapacity int
+ actionBuffer []ReadAction
+ actionIndex int
}
func NewJSONIn(reader *bufio.Reader) JSONIn {
@@ -26,6 +59,11 @@ func NewJSONIn(reader *bufio.Reader) JSONIn {
path: make([]Atom, 0, 256),
reader: reader,
structure: []JSONInStructure{JSONInRoot},
+ readBuffer: make([]Atom, 0, 256),
+ readIndex: 0,
+ readBufferCapacity: 256,
+ actionBuffer: make([]ReadAction, 0, 256),
+ actionIndex: 0,
}
}
@@ -127,159 +165,301 @@ func (in *JSONIn) readString(out []Atom) []Atom {
return out
}
-func (in *JSONIn) Read() (WalkItem, error) {
- restart:
- // TODO: Escaping
- // TODO: Don't allow trailing commas
- // TODO: Proper float parsing with e and stuff
- r, err := in.nextNonWsRune()
- if err != nil {
- return WalkItem {}, err
+// Returns the first full value of a list of atoms and also a boolean to indicate if there isn't a value at the beginning
+func firstValue(atoms []Atom) ([]Atom, bool) {
+ if len(atoms) == 0 {
+ return nil, true
+ }
+ if atoms[0].Typ != AtomStringTerminal {
+ return atoms[0:1], false
+ }
+ i := 1
+ for {
+ if i == len(atoms) {
+ return nil, true
+ }
+ if atoms[i].Typ == AtomStringTerminal {
+ return atoms[0:i+1], false
+ }
+ i++
}
- state := in.structure[len(in.structure) - 1]
- switch state {
- case JSONInMap:
- in.popPath()
- if r == '}' {
- in.structure[len(in.structure) - 1] = JSONInValueEnd
+}
+
+func (in *JSONIn) Read() (WalkItem, error) {
+ actionLoop: for {
+ if in.actionIndex == len(in.actionBuffer) {
+ in.actionIndex = 0
+ in.readIndex = 0
+ in.actionBuffer = in.actionBuffer[:0]
+ in.readBuffer = in.readBuffer[:0]
+ structure, err := in.fillReadBuffer(in.structure)
+ in.structure = structure
+ if len(in.actionBuffer) == 0 {
+ return WalkItem{}, err
+ }
+ }
+ action := in.actionBuffer[in.actionIndex]
+ switch a := action.(type) {
+ case ActionReadValue:
+ value, incomplete := firstValue(in.readBuffer[in.readIndex:])
+ if incomplete {
+ if in.readIndex == 0 {
+ newReadBuffer := make([]Atom, len(in.readBuffer), in.readBufferCapacity * 2)
+ in.readBufferCapacity *= 2
+ copy(newReadBuffer, in.readBuffer)
+ in.readBuffer = newReadBuffer
+ structure, _ := in.fillReadBuffer(in.structure)
+ in.structure = structure
+ continue actionLoop
+ }
+ copy(in.readBuffer, in.readBuffer[in.readIndex:])
+ in.readBuffer = in.readBuffer[:len(in.readBuffer) - in.readIndex]
+ in.readIndex = 0
+ copy(in.actionBuffer, in.actionBuffer[in.actionIndex:])
+ in.actionBuffer = in.actionBuffer[:len(in.actionBuffer) - in.actionIndex]
+ in.actionIndex = 0
+ structure, _ := in.fillReadBuffer(in.structure)
+ in.structure = structure
+ continue actionLoop
+ }
+ in.readIndex += len(value)
+ in.actionIndex++
return WalkItem {
- Value: []Atom{NewAtomTerminal(MapEnd)},
+ Value: value,
Path: in.path,
}, nil
+ case ActionAppendPath:
+ in.path = append(in.path, a.atoms...)
+ case ActionPopPath:
+ in.popPath()
+ case ActionIncrementPath:
+ prevIndex := in.path[len(in.path) - 1]
+ if prevIndex.Typ == AtomNull {
+ prevIndex.Typ = AtomNumber
+ prevIndex.data = math.Float64bits(0)
+ } else if prevIndex.Typ == AtomNumber {
+ prevIndex.data = math.Float64bits(math.Float64frombits(prevIndex.data) + 1)
+ } else {
+ panic("Invalid index in array input. Type: " + fmt.Sprintf("%v", prevIndex.Typ))
+ }
+ in.path[len(in.path) - 1] = prevIndex
+ default:
+ panic("Invalid ReadAction")
+ }
+ in.actionIndex++
+ }
+}
+
+func (in *JSONIn) AssertDone() {
+ if len(in.structure) != 1 || in.structure[0] != JSONInRoot {
+ panic("Input ended on incomplete JSON root")
+ }
+}
+
+func (in *JSONIn) pushReadBuffer(atom Atom) bool {
+ in.readBuffer = append(in.readBuffer, atom)
+ return len(in.readBuffer) == in.readBufferCapacity
+}
+
+func (in *JSONIn) pushActionBuffer(action ReadAction) {
+ in.actionBuffer = append(in.actionBuffer, action)
+}
+
+func (in *JSONIn) fillReadBuffer(structure []JSONInStructure) ([]JSONInStructure, error) {
+ valueStart: {
+ state := structure[len(structure) - 1]
+ switch state {
+ case JSONInString:
+ structure = structure[:len(structure) - 1]
+ goto string
+ case JSONInValueEnd:
+ structure = structure[:len(structure) - 1]
+ goto valueEnd
+ case JSONInMap:
+ goto mapValue
+ case JSONInArray:
+ goto arrayValue
+ case JSONInRoot:
+ goto value
+ }
+ }
+ value: {
+ r, err := in.nextNonWsRune()
+ if err != nil {
+ return structure, err
+ }
+ switch r {
+ case 'n':
+ in.requireString("ull")
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomNull()) {
+ return append(structure, JSONInValueEnd), nil
+ }
+ goto valueEnd
+ case 'f':
+ in.requireString("alse")
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomBool(false)) {
+ return append(structure, JSONInValueEnd), nil
+ }
+ goto valueEnd
+ case 't':
+ in.requireString("rue")
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomBool(true)) {
+ return append(structure, JSONInValueEnd), nil
+ }
+ goto valueEnd
+ case '"':
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomStringTerminal()) {
+ return append(structure, JSONInString), nil
+ }
+ goto string
+ case '{':
+ structure = append(structure, JSONInMap)
+ in.pushActionBuffer(ActionReadValue{})
+ in.pushActionBuffer(ActionAppendPath {[]Atom{NewAtomNull()}})
+ if in.pushReadBuffer(NewAtomTerminal(MapBegin)) {
+ return structure, nil
+ }
+ goto mapValue
+ case '[':
+ structure = append(structure, JSONInArray)
+ in.pushActionBuffer(ActionReadValue{})
+ in.pushActionBuffer(ActionAppendPath {[]Atom{NewAtomNull()}})
+ if in.pushReadBuffer(NewAtomTerminal(ArrayBegin)) {
+ return structure, nil
+ }
+ goto arrayValue
+ }
+ if isNumberRune(r) {
+ var builder strings.Builder
+ builder.WriteRune(r)
+ for {
+ r, _, err = in.reader.ReadRune()
+ if err != nil {
+ break
+ }
+ if !isNumberRune(r) {
+ in.reader.UnreadRune()
+ break
+ }
+ builder.WriteRune(r)
}
- if r != '"' {
- panic("Expected key, found something else")
+ number, parseError := strconv.ParseFloat(builder.String(), 64)
+ if parseError != nil {
+ panic("Invalid number")
}
- in.path = in.readString(in.path)
- r, err = in.nextNonWsRune()
- if err != nil {
- panic("Expected : got: " + err.Error())
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomNumber(number)) {
+ return append(structure, JSONInValueEnd), nil
}
- if r != ':' {
- panic("Expected : after key")
+ goto valueEnd
+ }
+ panic("Invalid JSON value starting with: " + string(r))
+ }
+ string: {
+ r, _, err := in.reader.ReadRune()
+ if err != nil {
+ panic("Missing closing terminal in string input: " + err.Error())
+ }
+ if r == '"' {
+ if in.pushReadBuffer(NewAtomStringTerminal()) {
+ return append(structure, JSONInValueEnd), nil
}
- r, err = in.nextNonWsRune()
+ goto valueEnd
+ }
+ if r == '\\' {
+ r, _, err = in.reader.ReadRune()
if err != nil {
- panic("Missing map value after key: " + err.Error())
- }
- case JSONInArray:
- if r == ']' {
- in.structure[len(in.structure) - 1] = JSONInValueEnd
- in.popPath()
- return WalkItem {
- Value: []Atom{NewAtomTerminal(ArrayEnd)},
- Path: in.path,
- }, nil
+ panic("Missing rune after \\")
}
- prevIndex := in.path[len(in.path) - 1]
- if prevIndex.Typ == AtomNull {
- prevIndex.Typ = AtomNumber
- prevIndex.data = math.Float64bits(0)
- } else if prevIndex.Typ == AtomNumber {
- prevIndex.data = math.Float64bits(math.Float64frombits(prevIndex.data) + 1)
- } else {
- panic("Invalid index in array input")
+ if in.pushReadBuffer(NewAtomStringRune(r)) {
+ return append(structure, JSONInString), nil
}
- in.path[len(in.path) - 1] = prevIndex
- case JSONInRoot:
- case JSONInValueEnd:
- in.structure = in.structure[:len(in.structure) - 1]
- underState := in.structure[len(in.structure) - 1]
- if underState == JSONInRoot {
- panic("More input after root JSON object ends")
- } else if underState == JSONInMap && r == '}' {
- in.structure[len(in.structure) - 1] = JSONInValueEnd
- in.popPath()
- return WalkItem {
- Value: []Atom{NewAtomTerminal(MapEnd)},
- Path: in.path,
- }, nil
- } else if underState == JSONInArray && r == ']' {
- in.structure[len(in.structure) - 1] = JSONInValueEnd
- in.popPath()
- return WalkItem {
- Value: []Atom{NewAtomTerminal(ArrayEnd)},
- Path: in.path,
- }, nil
+ goto string
+ }
+ if in.pushReadBuffer(NewAtomStringRune(r)) {
+ return append(structure, JSONInString), nil
+ }
+ goto string
+ }
+ valueEnd: {
+ r, err := in.nextNonWsRune()
+ if err != nil {
+ return structure, err
+ }
+ underState := structure[len(structure) - 1]
+ if underState == JSONInRoot {
+ panic("More input after root JSON object ends")
+ } else if underState == JSONInMap && r == '}' {
+ structure = structure[:len(structure) - 1]
+ in.pushActionBuffer(ActionPopPath{})
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomTerminal(MapEnd)) {
+ return append(structure, JSONInValueEnd), nil
}
- if r != ',' {
- panic("Expected , after JSON value, found: \"" + string(r) + "\"")
+ goto valueEnd
+ } else if underState == JSONInArray && r == ']' {
+ structure = structure[:len(structure) - 1]
+ in.pushActionBuffer(ActionPopPath{})
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomTerminal(ArrayEnd)) {
+ return append(structure, JSONInValueEnd), nil
}
- goto restart
- default:
- panic("Invalid JSONIn state")
- }
- switch r {
- case 'n':
- in.requireString("ull")
- in.structure = append(in.structure, JSONInValueEnd)
- return WalkItem {
- Value: []Atom{NewAtomNull()},
- Path: in.path,
- }, nil
- case 'f':
- in.requireString("alse")
- in.structure = append(in.structure, JSONInValueEnd)
- return WalkItem {
- Value: []Atom{NewAtomBool(false)},
- Path: in.path,
- }, nil
- case 't':
- in.requireString("rue")
- in.structure = append(in.structure, JSONInValueEnd)
- return WalkItem {
- Value: []Atom{NewAtomBool(true)},
- Path: in.path,
- }, nil
- case '"':
- value := make([]Atom, 0, 64)
- value = in.readString(value)
- in.structure = append(in.structure, JSONInValueEnd)
- return WalkItem {
- Value: value,
- Path: in.path,
- }, nil
- case '{':
- in.structure = append(in.structure, JSONInMap)
- in.path = append(in.path, NewAtomNull())
- return WalkItem {
- Value: []Atom{NewAtomTerminal(MapBegin)},
- Path: in.path[:len(in.path) - 1],
- }, nil
- case '[':
- in.structure = append(in.structure, JSONInArray)
- in.path = append(in.path, NewAtomNull())
- return WalkItem {
- Value: []Atom{NewAtomTerminal(ArrayBegin)},
- Path: in.path[:len(in.path) - 1],
- }, nil
+ goto valueEnd
+ }
+ if r != ',' {
+ panic("Expected , after JSON value, found: \"" + string(r) + "\"")
+ }
+ goto valueStart
}
- if isNumberRune(r) {
- var builder strings.Builder
- builder.WriteRune(r)
- for {
- r, _, err = in.reader.ReadRune()
- if err != nil || !isNumberRune(r) {
- break
+ mapValue: {
+ in.pushActionBuffer(ActionPopPath{})
+ r, err := in.nextNonWsRune()
+ if err != nil {
+ panic("Missing value inside object")
+ }
+ if r == '}' {
+ structure = structure[:len(structure) - 1]
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomTerminal(MapEnd)) {
+ return append(structure, JSONInValueEnd), nil
}
- builder.WriteRune(r)
+ goto valueEnd
}
- in.reader.UnreadRune()
- number, parseError := strconv.ParseFloat(builder.String(), 64)
- if parseError != nil {
- panic("Invalid number")
+ if r != '"' {
+ panic("Expected key found something else")
}
- in.structure = append(in.structure, JSONInValueEnd)
- return WalkItem {
- Value: []Atom{NewAtomNumber(number)},
- Path: in.path,
- }, nil
+ var keyAtoms []Atom
+ keyAtoms = in.readString(keyAtoms)
+ in.pushActionBuffer(ActionAppendPath {keyAtoms})
+ r, err = in.nextNonWsRune()
+ if err != nil {
+ panic("Expected : got: " + err.Error())
+ }
+ if r != ':' {
+ panic("Expected : after key")
+ }
+ goto value
}
- panic("Invalid JSON value")
-}
-
-func (in *JSONIn) AssertDone() {
- if len(in.structure) != 2 || in.structure[0] != JSONInRoot || in.structure[1] != JSONInValueEnd {
- panic("Input ended on incomplete JSON root")
+ arrayValue: {
+ r, err := in.nextNonWsRune()
+ if err != nil {
+ panic("Missing value inside array")
+ }
+ if r == ']' {
+ structure = structure[:len(structure) - 1]
+ in.pushActionBuffer(ActionPopPath{})
+ in.pushActionBuffer(ActionReadValue{})
+ if in.pushReadBuffer(NewAtomTerminal(ArrayEnd)) {
+ return append(structure, JSONInValueEnd), nil
+ }
+ goto valueEnd
+ }
+ in.reader.UnreadRune()
+ in.pushActionBuffer(ActionIncrementPath{})
+ goto value
}
}