rewrite in go

vendor/github.com/pelletier/go-toml/v2/internal/characters/ascii.go

@@ -0,0 +1,42 @@
+package characters
+
+var invalidAsciiTable = [256]bool{
+	0x00: true,
+	0x01: true,
+	0x02: true,
+	0x03: true,
+	0x04: true,
+	0x05: true,
+	0x06: true,
+	0x07: true,
+	0x08: true,
+	// 0x09 TAB
+	// 0x0A LF
+	0x0B: true,
+	0x0C: true,
+	// 0x0D CR
+	0x0E: true,
+	0x0F: true,
+	0x10: true,
+	0x11: true,
+	0x12: true,
+	0x13: true,
+	0x14: true,
+	0x15: true,
+	0x16: true,
+	0x17: true,
+	0x18: true,
+	0x19: true,
+	0x1A: true,
+	0x1B: true,
+	0x1C: true,
+	0x1D: true,
+	0x1E: true,
+	0x1F: true,
+	// 0x20 - 0x7E Printable ASCII characters
+	0x7F: true,
+}
+
+func InvalidAscii(b byte) bool {
+	return invalidAsciiTable[b]
+}

vendor/github.com/pelletier/go-toml/v2/internal/characters/utf8.go

@@ -0,0 +1,199 @@
+package characters
+
+import (
+	"unicode/utf8"
+)
+
+type utf8Err struct {
+	Index int
+	Size  int
+}
+
+func (u utf8Err) Zero() bool {
+	return u.Size == 0
+}
+
+// Verified that a given string is only made of valid UTF-8 characters allowed
+// by the TOML spec:
+//
+// Any Unicode character may be used except those that must be escaped:
+// quotation mark, backslash, and the control characters other than tab (U+0000
+// to U+0008, U+000A to U+001F, U+007F).
+//
+// It is a copy of the Go 1.17 utf8.Valid implementation, tweaked to exit early
+// when a character is not allowed.
+//
+// The returned utf8Err is Zero() if the string is valid, or contains the byte
+// index and size of the invalid character.
+//
+// quotation mark => already checked
+// backslash => already checked
+// 0-0x8 => invalid
+// 0x9 => tab, ok
+// 0xA - 0x1F => invalid
+// 0x7F => invalid
+func Utf8TomlValidAlreadyEscaped(p []byte) (err utf8Err) {
+	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
+	offset := 0
+	for len(p) >= 8 {
+		// Combining two 32 bit loads allows the same code to be used
+		// for 32 and 64 bit platforms.
+		// The compiler can generate a 32bit load for first32 and second32
+		// on many platforms. See test/codegen/memcombine.go.
+		first32 := uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
+		second32 := uint32(p[4]) | uint32(p[5])<<8 | uint32(p[6])<<16 | uint32(p[7])<<24
+		if (first32|second32)&0x80808080 != 0 {
+			// Found a non ASCII byte (>= RuneSelf).
+			break
+		}
+
+		for i, b := range p[:8] {
+			if InvalidAscii(b) {
+				err.Index = offset + i
+				err.Size = 1
+				return
+			}
+		}
+
+		p = p[8:]
+		offset += 8
+	}
+	n := len(p)
+	for i := 0; i < n; {
+		pi := p[i]
+		if pi < utf8.RuneSelf {
+			if InvalidAscii(pi) {
+				err.Index = offset + i
+				err.Size = 1
+				return
+			}
+			i++
+			continue
+		}
+		x := first[pi]
+		if x == xx {
+			// Illegal starter byte.
+			err.Index = offset + i
+			err.Size = 1
+			return
+		}
+		size := int(x & 7)
+		if i+size > n {
+			// Short or invalid.
+			err.Index = offset + i
+			err.Size = n - i
+			return
+		}
+		accept := acceptRanges[x>>4]
+		if c := p[i+1]; c < accept.lo || accept.hi < c {
+			err.Index = offset + i
+			err.Size = 2
+			return
+		} else if size == 2 {
+		} else if c := p[i+2]; c < locb || hicb < c {
+			err.Index = offset + i
+			err.Size = 3
+			return
+		} else if size == 3 {
+		} else if c := p[i+3]; c < locb || hicb < c {
+			err.Index = offset + i
+			err.Size = 4
+			return
+		}
+		i += size
+	}
+	return
+}
+
+// Return the size of the next rune if valid, 0 otherwise.
+func Utf8ValidNext(p []byte) int {
+	c := p[0]
+
+	if c < utf8.RuneSelf {
+		if InvalidAscii(c) {
+			return 0
+		}
+		return 1
+	}
+
+	x := first[c]
+	if x == xx {
+		// Illegal starter byte.
+		return 0
+	}
+	size := int(x & 7)
+	if size > len(p) {
+		// Short or invalid.
+		return 0
+	}
+	accept := acceptRanges[x>>4]
+	if c := p[1]; c < accept.lo || accept.hi < c {
+		return 0
+	} else if size == 2 {
+	} else if c := p[2]; c < locb || hicb < c {
+		return 0
+	} else if size == 3 {
+	} else if c := p[3]; c < locb || hicb < c {
+		return 0
+	}
+
+	return size
+}
+
+// acceptRange gives the range of valid values for the second byte in a UTF-8
+// sequence.
+type acceptRange struct {
+	lo uint8 // lowest value for second byte.
+	hi uint8 // highest value for second byte.
+}
+
+// acceptRanges has size 16 to avoid bounds checks in the code that uses it.
+var acceptRanges = [16]acceptRange{
+	0: {locb, hicb},
+	1: {0xA0, hicb},
+	2: {locb, 0x9F},
+	3: {0x90, hicb},
+	4: {locb, 0x8F},
+}
+
+// first is information about the first byte in a UTF-8 sequence.
+var first = [256]uint8{
+	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x00-0x0F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x10-0x1F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x20-0x2F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x30-0x3F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x40-0x4F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x50-0x5F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x60-0x6F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x70-0x7F
+	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0x80-0x8F
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0x90-0x9F
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xA0-0xAF
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xB0-0xBF
+	xx, xx, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, // 0xC0-0xCF
+	s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, // 0xD0-0xDF
+	s2, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s4, s3, s3, // 0xE0-0xEF
+	s5, s6, s6, s6, s7, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xF0-0xFF
+}
+
+const (
+	// The default lowest and highest continuation byte.
+	locb = 0b10000000
+	hicb = 0b10111111
+
+	// These names of these constants are chosen to give nice alignment in the
+	// table below. The first nibble is an index into acceptRanges or F for
+	// special one-byte cases. The second nibble is the Rune length or the
+	// Status for the special one-byte case.
+	xx = 0xF1 // invalid: size 1
+	as = 0xF0 // ASCII: size 1
+	s1 = 0x02 // accept 0, size 2
+	s2 = 0x13 // accept 1, size 3
+	s3 = 0x03 // accept 0, size 3
+	s4 = 0x23 // accept 2, size 3
+	s5 = 0x34 // accept 3, size 4
+	s6 = 0x04 // accept 0, size 4
+	s7 = 0x44 // accept 4, size 4
+)

vendor/github.com/pelletier/go-toml/v2/internal/danger/danger.go

@@ -0,0 +1,65 @@
+package danger
+
+import (
+	"fmt"
+	"reflect"
+	"unsafe"
+)
+
+const maxInt = uintptr(int(^uint(0) >> 1))
+
+func SubsliceOffset(data []byte, subslice []byte) int {
+	datap := (*reflect.SliceHeader)(unsafe.Pointer(&data))
+	hlp := (*reflect.SliceHeader)(unsafe.Pointer(&subslice))
+
+	if hlp.Data < datap.Data {
+		panic(fmt.Errorf("subslice address (%d) is before data address (%d)", hlp.Data, datap.Data))
+	}
+	offset := hlp.Data - datap.Data
+
+	if offset > maxInt {
+		panic(fmt.Errorf("slice offset larger than int (%d)", offset))
+	}
+
+	intoffset := int(offset)
+
+	if intoffset > datap.Len {
+		panic(fmt.Errorf("slice offset (%d) is farther than data length (%d)", intoffset, datap.Len))
+	}
+
+	if intoffset+hlp.Len > datap.Len {
+		panic(fmt.Errorf("slice ends (%d+%d) is farther than data length (%d)", intoffset, hlp.Len, datap.Len))
+	}
+
+	return intoffset
+}
+
+func BytesRange(start []byte, end []byte) []byte {
+	if start == nil || end == nil {
+		panic("cannot call BytesRange with nil")
+	}
+	startp := (*reflect.SliceHeader)(unsafe.Pointer(&start))
+	endp := (*reflect.SliceHeader)(unsafe.Pointer(&end))
+
+	if startp.Data > endp.Data {
+		panic(fmt.Errorf("start pointer address (%d) is after end pointer address (%d)", startp.Data, endp.Data))
+	}
+
+	l := startp.Len
+	endLen := int(endp.Data-startp.Data) + endp.Len
+	if endLen > l {
+		l = endLen
+	}
+
+	if l > startp.Cap {
+		panic(fmt.Errorf("range length is larger than capacity"))
+	}
+
+	return start[:l]
+}
+
+func Stride(ptr unsafe.Pointer, size uintptr, offset int) unsafe.Pointer {
+	// TODO: replace with unsafe.Add when Go 1.17 is released
+	//   https://github.com/golang/go/issues/40481
+	return unsafe.Pointer(uintptr(ptr) + uintptr(int(size)*offset))
+}

vendor/github.com/pelletier/go-toml/v2/internal/danger/typeid.go

@@ -0,0 +1,23 @@
+package danger
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// typeID is used as key in encoder and decoder caches to enable using
+// the optimize runtime.mapaccess2_fast64 function instead of the more
+// expensive lookup if we were to use reflect.Type as map key.
+//
+// typeID holds the pointer to the reflect.Type value, which is unique
+// in the program.
+//
+// https://github.com/segmentio/encoding/blob/master/json/codec.go#L59-L61
+type TypeID unsafe.Pointer
+
+func MakeTypeID(t reflect.Type) TypeID {
+	// reflect.Type has the fields:
+	// typ unsafe.Pointer
+	// ptr unsafe.Pointer
+	return TypeID((*[2]unsafe.Pointer)(unsafe.Pointer(&t))[1])
+}

vendor/github.com/pelletier/go-toml/v2/internal/tracker/key.go

@@ -0,0 +1,48 @@
+package tracker
+
+import "github.com/pelletier/go-toml/v2/unstable"
+
+// KeyTracker is a tracker that keeps track of the current Key as the AST is
+// walked.
+type KeyTracker struct {
+	k []string
+}
+
+// UpdateTable sets the state of the tracker with the AST table node.
+func (t *KeyTracker) UpdateTable(node *unstable.Node) {
+	t.reset()
+	t.Push(node)
+}
+
+// UpdateArrayTable sets the state of the tracker with the AST array table node.
+func (t *KeyTracker) UpdateArrayTable(node *unstable.Node) {
+	t.reset()
+	t.Push(node)
+}
+
+// Push the given key on the stack.
+func (t *KeyTracker) Push(node *unstable.Node) {
+	it := node.Key()
+	for it.Next() {
+		t.k = append(t.k, string(it.Node().Data))
+	}
+}
+
+// Pop key from stack.
+func (t *KeyTracker) Pop(node *unstable.Node) {
+	it := node.Key()
+	for it.Next() {
+		t.k = t.k[:len(t.k)-1]
+	}
+}
+
+// Key returns the current key
+func (t *KeyTracker) Key() []string {
+	k := make([]string, len(t.k))
+	copy(k, t.k)
+	return k
+}
+
+func (t *KeyTracker) reset() {
+	t.k = t.k[:0]
+}

vendor/github.com/pelletier/go-toml/v2/internal/tracker/seen.go

@@ -0,0 +1,356 @@
+package tracker
+
+import (
+	"bytes"
+	"fmt"
+	"sync"
+
+	"github.com/pelletier/go-toml/v2/unstable"
+)
+
+type keyKind uint8
+
+const (
+	invalidKind keyKind = iota
+	valueKind
+	tableKind
+	arrayTableKind
+)
+
+func (k keyKind) String() string {
+	switch k {
+	case invalidKind:
+		return "invalid"
+	case valueKind:
+		return "value"
+	case tableKind:
+		return "table"
+	case arrayTableKind:
+		return "array table"
+	}
+	panic("missing keyKind string mapping")
+}
+
+// SeenTracker tracks which keys have been seen with which TOML type to flag
+// duplicates and mismatches according to the spec.
+//
+// Each node in the visited tree is represented by an entry. Each entry has an
+// identifier, which is provided by a counter. Entries are stored in the array
+// entries. As new nodes are discovered (referenced for the first time in the
+// TOML document), entries are created and appended to the array. An entry
+// points to its parent using its id.
+//
+// To find whether a given key (sequence of []byte) has already been visited,
+// the entries are linearly searched, looking for one with the right name and
+// parent id.
+//
+// Given that all keys appear in the document after their parent, it is
+// guaranteed that all descendants of a node are stored after the node, this
+// speeds up the search process.
+//
+// When encountering [[array tables]], the descendants of that node are removed
+// to allow that branch of the tree to be "rediscovered". To maintain the
+// invariant above, the deletion process needs to keep the order of entries.
+// This results in more copies in that case.
+type SeenTracker struct {
+	entries    []entry
+	currentIdx int
+}
+
+var pool sync.Pool
+
+func (s *SeenTracker) reset() {
+	// Always contains a root element at index 0.
+	s.currentIdx = 0
+	if len(s.entries) == 0 {
+		s.entries = make([]entry, 1, 2)
+	} else {
+		s.entries = s.entries[:1]
+	}
+	s.entries[0].child = -1
+	s.entries[0].next = -1
+}
+
+type entry struct {
+	// Use -1 to indicate no child or no sibling.
+	child int
+	next  int
+
+	name     []byte
+	kind     keyKind
+	explicit bool
+	kv       bool
+}
+
+// Find the index of the child of parentIdx with key k. Returns -1 if
+// it does not exist.
+func (s *SeenTracker) find(parentIdx int, k []byte) int {
+	for i := s.entries[parentIdx].child; i >= 0; i = s.entries[i].next {
+		if bytes.Equal(s.entries[i].name, k) {
+			return i
+		}
+	}
+	return -1
+}
+
+// Remove all descendants of node at position idx.
+func (s *SeenTracker) clear(idx int) {
+	if idx >= len(s.entries) {
+		return
+	}
+
+	for i := s.entries[idx].child; i >= 0; {
+		next := s.entries[i].next
+		n := s.entries[0].next
+		s.entries[0].next = i
+		s.entries[i].next = n
+		s.entries[i].name = nil
+		s.clear(i)
+		i = next
+	}
+
+	s.entries[idx].child = -1
+}
+
+func (s *SeenTracker) create(parentIdx int, name []byte, kind keyKind, explicit bool, kv bool) int {
+	e := entry{
+		child: -1,
+		next:  s.entries[parentIdx].child,
+
+		name:     name,
+		kind:     kind,
+		explicit: explicit,
+		kv:       kv,
+	}
+	var idx int
+	if s.entries[0].next >= 0 {
+		idx = s.entries[0].next
+		s.entries[0].next = s.entries[idx].next
+		s.entries[idx] = e
+	} else {
+		idx = len(s.entries)
+		s.entries = append(s.entries, e)
+	}
+
+	s.entries[parentIdx].child = idx
+
+	return idx
+}
+
+func (s *SeenTracker) setExplicitFlag(parentIdx int) {
+	for i := s.entries[parentIdx].child; i >= 0; i = s.entries[i].next {
+		if s.entries[i].kv {
+			s.entries[i].explicit = true
+			s.entries[i].kv = false
+		}
+		s.setExplicitFlag(i)
+	}
+}
+
+// CheckExpression takes a top-level node and checks that it does not contain
+// keys that have been seen in previous calls, and validates that types are
+// consistent.
+func (s *SeenTracker) CheckExpression(node *unstable.Node) error {
+	if s.entries == nil {
+		s.reset()
+	}
+	switch node.Kind {
+	case unstable.KeyValue:
+		return s.checkKeyValue(node)
+	case unstable.Table:
+		return s.checkTable(node)
+	case unstable.ArrayTable:
+		return s.checkArrayTable(node)
+	default:
+		panic(fmt.Errorf("this should not be a top level node type: %s", node.Kind))
+	}
+}
+
+func (s *SeenTracker) checkTable(node *unstable.Node) error {
+	if s.currentIdx >= 0 {
+		s.setExplicitFlag(s.currentIdx)
+	}
+
+	it := node.Key()
+
+	parentIdx := 0
+
+	// This code is duplicated in checkArrayTable. This is because factoring
+	// it in a function requires to copy the iterator, or allocate it to the
+	// heap, which is not cheap.
+	for it.Next() {
+		if it.IsLast() {
+			break
+		}
+
+		k := it.Node().Data
+
+		idx := s.find(parentIdx, k)
+
+		if idx < 0 {
+			idx = s.create(parentIdx, k, tableKind, false, false)
+		} else {
+			entry := s.entries[idx]
+			if entry.kind == valueKind {
+				return fmt.Errorf("toml: expected %s to be a table, not a %s", string(k), entry.kind)
+			}
+		}
+		parentIdx = idx
+	}
+
+	k := it.Node().Data
+	idx := s.find(parentIdx, k)
+
+	if idx >= 0 {
+		kind := s.entries[idx].kind
+		if kind != tableKind {
+			return fmt.Errorf("toml: key %s should be a table, not a %s", string(k), kind)
+		}
+		if s.entries[idx].explicit {
+			return fmt.Errorf("toml: table %s already exists", string(k))
+		}
+		s.entries[idx].explicit = true
+	} else {
+		idx = s.create(parentIdx, k, tableKind, true, false)
+	}
+
+	s.currentIdx = idx
+
+	return nil
+}
+
+func (s *SeenTracker) checkArrayTable(node *unstable.Node) error {
+	if s.currentIdx >= 0 {
+		s.setExplicitFlag(s.currentIdx)
+	}
+
+	it := node.Key()
+
+	parentIdx := 0
+
+	for it.Next() {
+		if it.IsLast() {
+			break
+		}
+
+		k := it.Node().Data
+
+		idx := s.find(parentIdx, k)
+
+		if idx < 0 {
+			idx = s.create(parentIdx, k, tableKind, false, false)
+		} else {
+			entry := s.entries[idx]
+			if entry.kind == valueKind {
+				return fmt.Errorf("toml: expected %s to be a table, not a %s", string(k), entry.kind)
+			}
+		}
+
+		parentIdx = idx
+	}
+
+	k := it.Node().Data
+	idx := s.find(parentIdx, k)
+
+	if idx >= 0 {
+		kind := s.entries[idx].kind
+		if kind != arrayTableKind {
+			return fmt.Errorf("toml: key %s already exists as a %s,  but should be an array table", kind, string(k))
+		}
+		s.clear(idx)
+	} else {
+		idx = s.create(parentIdx, k, arrayTableKind, true, false)
+	}
+
+	s.currentIdx = idx
+
+	return nil
+}
+
+func (s *SeenTracker) checkKeyValue(node *unstable.Node) error {
+	parentIdx := s.currentIdx
+	it := node.Key()
+
+	for it.Next() {
+		k := it.Node().Data
+
+		idx := s.find(parentIdx, k)
+
+		if idx < 0 {
+			idx = s.create(parentIdx, k, tableKind, false, true)
+		} else {
+			entry := s.entries[idx]
+			if it.IsLast() {
+				return fmt.Errorf("toml: key %s is already defined", string(k))
+			} else if entry.kind != tableKind {
+				return fmt.Errorf("toml: expected %s to be a table, not a %s", string(k), entry.kind)
+			} else if entry.explicit {
+				return fmt.Errorf("toml: cannot redefine table %s that has already been explicitly defined", string(k))
+			}
+		}
+
+		parentIdx = idx
+	}
+
+	s.entries[parentIdx].kind = valueKind
+
+	value := node.Value()
+
+	switch value.Kind {
+	case unstable.InlineTable:
+		return s.checkInlineTable(value)
+	case unstable.Array:
+		return s.checkArray(value)
+	}
+
+	return nil
+}
+
+func (s *SeenTracker) checkArray(node *unstable.Node) error {
+	it := node.Children()
+	for it.Next() {
+		n := it.Node()
+		switch n.Kind {
+		case unstable.InlineTable:
+			err := s.checkInlineTable(n)
+			if err != nil {
+				return err
+			}
+		case unstable.Array:
+			err := s.checkArray(n)
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func (s *SeenTracker) checkInlineTable(node *unstable.Node) error {
+	if pool.New == nil {
+		pool.New = func() interface{} {
+			return &SeenTracker{}
+		}
+	}
+
+	s = pool.Get().(*SeenTracker)
+	s.reset()
+
+	it := node.Children()
+	for it.Next() {
+		n := it.Node()
+		err := s.checkKeyValue(n)
+		if err != nil {
+			return err
+		}
+	}
+
+	// As inline tables are self-contained, the tracker does not
+	// need to retain the details of what they contain. The
+	// keyValue element that creates the inline table is kept to
+	// mark the presence of the inline table and prevent
+	// redefinition of its keys: check* functions cannot walk into
+	// a value.
+	pool.Put(s)
+	return nil
+}

vendor/github.com/pelletier/go-toml/v2/internal/tracker/tracker.go

@@ -0,0 +1 @@
+package tracker