decode: Add float 80 reader

Rename *d.Bits to UintBits as it return a uint
Add *d.Bits that return []byte

format/asn1/asn1_ber.go

@@ -202,7 +202,7 @@ func decodeASN1BERValue(d *decode.D, bib *bitio.Buffer, sb *strings.Builder, par
 		case form == formConstructed || tag == universalTypeSequence || tag == universalTypeSet:
 			d.FieldArray("constructed", func(d *decode.D) {
 				for !d.End() {
-					if length == lengthIndefinite && d.PeekBits(16) == lengthEndMarker {
+					if length == lengthIndefinite && d.PeekUintBits(16) == lengthEndMarker {
 						break
 					}
 

format/bencode/bencode.go

@@ -71,14 +71,14 @@ func decodeBencodeValue(d *decode.D) {
 		d.FieldUTF8("end", 1, d.StrAssert("e"))
 	case "l":
 		d.FieldArray("values", func(d *decode.D) {
-			for d.PeekBits(8) != 'e' {
+			for d.PeekUintBits(8) != 'e' {
 				d.FieldStruct("value", decodeBencodeValue)
 			}
 		})
 		d.FieldUTF8("end", 1, d.StrAssert("e"))
 	case "d":
 		d.FieldArray("pairs", func(d *decode.D) {
-			for d.PeekBits(8) != 'e' {
+			for d.PeekUintBits(8) != 'e' {
 				d.FieldStruct("pair", func(d *decode.D) {
 					d.FieldStruct("key", decodeBencodeValue)
 					d.FieldStruct("value", decodeBencodeValue)

format/bitcoin/bitcoin_block.go

@@ -42,7 +42,7 @@ func decodeBitcoinBlock(d *decode.D) any {
 	size := d.BitsLeft()
 
 	if bbi.HasHeader {
-		magic := d.PeekBits(32)
+		magic := d.PeekUintBits(32)
 		switch magic {
 		case 0xf9beb4d9,
 			0x0b110907,

format/bitcoin/bitcoin_script.go

@@ -171,7 +171,7 @@ func decodeBitcoinScript(d *decode.D) any {
 	}
 
 	for !d.End() {
-		opcode := byte(d.PeekBits(8))
+		opcode := byte(d.PeekUintBits(8))
 		ope, ok := opcodeEntries.lookup(opcode)
 		if !ok {
 			d.Fatalf("unknown opcode %x", opcode)

format/bitcoin/bitcoin_transaction.go

@@ -49,7 +49,7 @@ func decodeBitcoinTranscation(d *decode.D) any {
 
 	d.FieldU32("version")
 	witness := false
-	if d.PeekBits(8) == 0 {
+	if d.PeekUintBits(8) == 0 {
 		witness = true
 		d.FieldU8("marker")
 		d.FieldU8("flag")

format/bzip2/bzip2.go

@@ -127,7 +127,7 @@ func bzip2Decode(d *decode.D) any {
 		compressedSize := (readCompressedSize - compressedStart) - footerByteSize*8
 		for i := 0; i < 8; i++ {
 			d.SeekAbs(compressedStart + compressedSize)
-			if d.PeekBits(48) == footerMagic {
+			if d.PeekUintBits(48) == footerMagic {
 				break
 			}
 			compressedSize--

format/cbor/cbor.go

@@ -124,7 +124,7 @@ func decodeCBORValue(d *decode.D) any {
 			if shortCount == shortCountIndefinite {
 				bb := &bytes.Buffer{}
 				d.FieldArray("items", func(d *decode.D) {
-					for d.PeekBits(8) != breakMarker {
+					for d.PeekUintBits(8) != breakMarker {
 						d.FieldStruct("item", func(d *decode.D) {
 							v := decodeCBORValue(d)
 							switch v := v.(type) {
@@ -149,7 +149,7 @@ func decodeCBORValue(d *decode.D) any {
 			if shortCount == shortCountIndefinite {
 				sb := &strings.Builder{}
 				d.FieldArray("items", func(d *decode.D) {
-					for d.PeekBits(8) != breakMarker {
+					for d.PeekUintBits(8) != breakMarker {
 						d.FieldStruct("item", func(d *decode.D) {
 							v := decodeCBORValue(d)
 							switch v := v.(type) {
@@ -171,7 +171,7 @@ func decodeCBORValue(d *decode.D) any {
 		majorTypeArray: {s: scalar.Uint{Sym: "array"}, d: func(d *decode.D, shortCount uint64, count uint64) any {
 			d.FieldArray("elements", func(d *decode.D) {
 				for i := uint64(0); true; i++ {
-					if shortCount == shortCountIndefinite && d.PeekBits(8) == breakMarker {
+					if shortCount == shortCountIndefinite && d.PeekUintBits(8) == breakMarker {
 						break
 					} else if i >= count {
 						break
@@ -187,7 +187,7 @@ func decodeCBORValue(d *decode.D) any {
 		majorTypeMap: {s: scalar.Uint{Sym: "map"}, d: func(d *decode.D, shortCount uint64, count uint64) any {
 			d.FieldArray("pairs", func(d *decode.D) {
 				for i := uint64(0); true; i++ {
-					if shortCount == shortCountIndefinite && d.PeekBits(8) == breakMarker {
+					if shortCount == shortCountIndefinite && d.PeekUintBits(8) == breakMarker {
 						break
 					} else if i >= count {
 						break

format/dns/dns.go

@@ -141,7 +141,7 @@ func fieldDecodeLabel(d *decode.D, pointerOffset int64, name string) {
 			seenTermintor := false
 			for !seenTermintor {
 				d.FieldStruct("label", func(d *decode.D) {
-					if d.PeekBits(2) == 0b11 {
+					if d.PeekUintBits(2) == 0b11 {
 						d.FieldU2("is_pointer")
 						pointer := d.FieldU14("pointer")
 						if endPos == 0 {

format/gif/gif.go

@@ -72,7 +72,7 @@ func gifDecode(d *decode.D) any {
 	d.FieldArray("blocks", func(d *decode.D) {
 	blocks:
 		for {
-			switch d.PeekBits(8) {
+			switch d.PeekUintBits(8) {
 			case ';':
 				break blocks
 			case '!': /* "!" */
@@ -89,7 +89,7 @@ func gifDecode(d *decode.D) any {
 							d.FieldStruct("func_data_byte", func(d *decode.D) {
 								byteCount := d.FieldU8("byte_count")
 								b := d.FieldRawLen("data", int64(byteCount*8))
-								if d.PeekBits(8) == 0 {
+								if d.PeekUintBits(8) == 0 {
 									d.FieldU8("terminator")
 									seenTerminator = true
 								}
@@ -135,7 +135,7 @@ func gifDecode(d *decode.D) any {
 							d.FieldStruct("func_data_byte", func(d *decode.D) {
 								byteCount := d.FieldU8("byte_count")
 								d.FieldRawLen("data", int64(byteCount*8))
-								if d.PeekBits(8) == 0 {
+								if d.PeekUintBits(8) == 0 {
 									d.FieldU8("terminator")
 									seenTerminator = true
 								}

format/id3/id3v1.go

@@ -21,7 +21,7 @@ func init() {
 func id3v1Decode(d *decode.D) any {
 	d.AssertAtLeastBitsLeft(128 * 8)
 	d.FieldUTF8("magic", 3, d.StrAssert("TAG"))
-	if d.PeekBits(8) == uint64('+') {
+	if d.PeekUintBits(8) == uint64('+') {
 		d.Errorf("looks like id3v11")
 	}
 	d.FieldUTF8NullFixedLen("song_name", 30)

format/id3/id3v2.go

@@ -315,7 +315,7 @@ func textNullLenFn(encoding int, notFoundFixedBytes int) func(d *decode.D) strin
 
 		d.SeekRel(nullLen * 8)
 		// seems sometimes utf16 etc has one exta null byte
-		if nullLen > 1 && d.PeekBits(8) == 0 {
+		if nullLen > 1 && d.PeekUintBits(8) == 0 {
 			d.SeekRel(8)
 		}
 
@@ -592,7 +592,7 @@ func decodeFrame(d *decode.D, version int) uint64 {
 func decodeFrames(d *decode.D, version int, size uint64) {
 	d.FieldArray("frames", func(d *decode.D) {
 		for size > 0 {
-			if d.PeekBits(8) == 0 {
+			if d.PeekUintBits(8) == 0 {
 				return
 			}
 

format/jpeg/jpeg.go

@@ -180,7 +180,7 @@ func jpegDecode(d *decode.D) any {
 			if inECD {
 				ecdLen := int64(0)
 				for {
-					if d.PeekBits(8) == 0xff && d.PeekBits(16) != 0xff00 {
+					if d.PeekUintBits(8) == 0xff && d.PeekUintBits(16) != 0xff00 {
 						break
 					}
 					d.SeekRel(8)

format/matroska/matroska.go

@@ -445,7 +445,7 @@ func matroskaDecode(d *decode.D) any {
 	d.ArgAs(&mi)
 
 	ebmlHeaderID := uint64(0x1a45dfa3)
-	if d.PeekBits(32) != ebmlHeaderID {
+	if d.PeekUintBits(32) != ebmlHeaderID {
 		d.Errorf("no EBML header found")
 	}
 	dc := &decodeContext{tracks: []*track{}}

format/mp4/boxes.go

@@ -295,7 +295,7 @@ func decodeBoxesWithParentData(ctx *decodeContext, d *decode.D, parentData any,
 
 	if d.BitsLeft() > 0 {
 		// "Some sample descriptions terminate with four zero bytes that are not otherwise indicated."
-		if d.BitsLeft() >= 32 && d.PeekBits(32) == 0 {
+		if d.BitsLeft() >= 32 && d.PeekUintBits(32) == 0 {
 			d.FieldU32("zero_terminator")
 		}
 		if d.BitsLeft() > 0 {
@@ -904,7 +904,7 @@ func decodeBox(ctx *decodeContext, d *decode.D, typ string) {
 		decodeBoxes(ctx, d)
 	case "meta":
 		// TODO: meta box sometimes has a 4 byte unknown field? (flag/version?)
-		maybeFlags := d.PeekBits(32)
+		maybeFlags := d.PeekUintBits(32)
 		if maybeFlags == 0 {
 			// TODO: rename?
 			d.FieldU32("maybe_flags")
@@ -1687,7 +1687,7 @@ func decodeBox(ctx *decodeContext, d *decode.D, typ string) {
 			// TODO: better probe? ffmpeg uses box name heuristics?
 			// if 16 length field seems to match assume box with length, language and value
 			// otherwise decode as box with value rest of box
-			probeLength := d.PeekBits(16)
+			probeLength := d.PeekUintBits(16)
 			// +2 for length field, +2 for language field
 			if (probeLength+2+2)*8 == uint64(d.BitsLeft()) {
 				length := d.FieldU16("length")

format/mpeg/avc_pps.go

@@ -17,7 +17,7 @@ func init() {
 
 func moreRBSPData(d *decode.D) bool {
 	l := d.BitsLeft()
-	return l >= 8 && d.PeekBits(8) != 0b1000_0000
+	return l >= 8 && d.PeekUintBits(8) != 0b1000_0000
 }
 
 func avcPPSDecode(d *decode.D) any {

format/mpeg/mpeg_pes.go

@@ -36,7 +36,7 @@ type subStream struct {
 func pesDecode(d *decode.D) any {
 	substreams := map[int]*subStream{}
 
-	prefix := d.PeekBits(24)
+	prefix := d.PeekUintBits(24)
 	if prefix != 0b0000_0000_0000_0000_0000_0001 {
 		d.Errorf("no pes prefix found")
 	}

format/mpeg/mpeg_pes_packet.go

@@ -97,7 +97,7 @@ func pesPacketDecode(d *decode.D) any {
 
 		}
 	case startCode == packHeader:
-		isMPEG2 := d.PeekBits(2) == 0b01
+		isMPEG2 := d.PeekUintBits(2) == 0b01
 		if isMPEG2 {
 			d.FieldU2("marker_bits0", mpegVersion)
 		} else {
@@ -140,7 +140,7 @@ func pesPacketDecode(d *decode.D) any {
 		d.FieldU1("packet_rate_restriction_flag")
 		d.FieldU7("reserved")
 		d.FieldArray("stream_bound_entries", func(d *decode.D) {
-			for d.PeekBits(1) == 1 {
+			for d.PeekUintBits(1) == 1 {
 				d.FieldStruct("stream_bound_entry", func(d *decode.D) {
 					d.FieldU8("stream_id")
 					d.FieldU2("skip0")

format/mpeg/mpeg_spu.go

@@ -48,7 +48,7 @@ var commandNames = scalar.UintMapSymStr{
 }
 
 func rleValue(d *decode.D) (uint64, uint64, int) {
-	p := uint(d.PeekBits(8))
+	p := uint(d.PeekUintBits(8))
 
 	// match zero prefix
 	switch {

format/riff/aiff.go

@@ -4,7 +4,6 @@ package riff
 
 import (
 	"github.com/wader/fq/format"
-	"github.com/wader/fq/internal/mathex"
 	"github.com/wader/fq/pkg/decode"
 	"github.com/wader/fq/pkg/interp"
 	"github.com/wader/fq/pkg/scalar"
@@ -81,9 +80,7 @@ func aiffDecode(d *decode.D) any {
 				d.FieldU32("num_sample_frames")
 				d.FieldU16("sample_size")
 				// TODO: support big float?
-				d.FieldFltFn("sample_rate", func(d *decode.D) float64 {
-					return mathex.NewFloat80FromBytes(d.BytesLen(10)).Float64()
-				})
+				d.FieldF80("sample_rate")
 				return false, nil
 			case "SSND":
 				d.FieldU32("offset")

format/rtmp/amf0.go

@@ -77,7 +77,7 @@ func amf0DecodeValue(d *decode.D) {
 						l := d.FieldU16("length")
 						d.FieldUTF8("value", int(l))
 					})
-					typ = d.PeekBits(8)
+					typ = d.PeekUintBits(8)
 					d.FieldStruct("value", amf0DecodeValue)
 				})
 			}
@@ -98,7 +98,7 @@ func amf0DecodeValue(d *decode.D) {
 						l := d.FieldU16("length")
 						d.FieldUTF8("value", int(l))
 					})
-					typ = d.PeekBits(8)
+					typ = d.PeekUintBits(8)
 					d.FieldStruct("value", amf0DecodeValue)
 				})
 			}
@@ -134,7 +134,7 @@ func amf0DecodeValue(d *decode.D) {
 						l := d.FieldU16("length")
 						d.FieldUTF8("value", int(l))
 					})
-					typ = d.PeekBits(8)
+					typ = d.PeekUintBits(8)
 					d.FieldStruct("value", amf0DecodeValue)
 				})
 			}

format/rtmp/rtmp.go

@@ -368,7 +368,7 @@ func rtmpDecode(d *decode.D) any {
 				var chunkSteamID uint64
 
 				fmt := d.FieldU2("fmt")
-				switch d.PeekBits(6) {
+				switch d.PeekUintBits(6) {
 				case 0:
 					// 64-319: 2 byte
 					d.FieldU6("chunk_stream_id_prefix")

format/tls/tls.go

@@ -695,7 +695,7 @@ func decodeTLS(d *decode.D) any {
 	tc.server.currentCipherSuit = ciphersuites.TLS_NULL_WITH_NULL_NULL
 	tc.server.nextCipherSuit = ciphersuites.TLS_NULL_WITH_NULL_NULL
 
-	firstByte := d.PeekBits(8)
+	firstByte := d.PeekUintBits(8)
 	if firstByte&0x80 != 0 {
 		d.FieldStruct("ssl_v2", func(d *decode.D) {
 			decodeV2ClientHello(d, tc)

pkg/decode/decode.go

@@ -306,7 +306,7 @@ func (d *D) SharedReadBuf(n int) []byte {
 	if len(*d.readBuf) < n {
 		*d.readBuf = make([]byte, n)
 	}
-	return *d.readBuf
+	return (*d.readBuf)[:n]
 }
 
 func (d *D) FillGaps(r ranges.Range, namePrefix string) {
@@ -370,34 +370,55 @@ func (d *D) IOPanic(err error, op string) {
 	panic(IOError{Err: err, Pos: d.Pos(), Op: op})
 }
 
+// TryBits reads nBits bits from buffer
+func (d *D) TryBits(nBits int) ([]byte, error) {
+	if nBits < 0 {
+		return nil, fmt.Errorf("nBits must be >= 0 (%d)", nBits)
+	}
+	buf := d.SharedReadBuf(int(bitio.BitsByteCount(int64(nBits))))
+	_, err := bitio.ReadFull(d.bitBuf, buf, int64(nBits))
+	if err != nil {
+		return nil, err
+	}
+
+	return buf[:], nil
+}
+
 // Bits reads nBits bits from buffer
-func (d *D) TryBits(nBits int) (uint64, error) {
+func (d *D) Bits(nBits int) []byte {
+	b, err := d.TryBits(nBits)
+	if err != nil {
+		panic(IOError{Err: err, Op: "Bits", ReadSize: int64(nBits), Pos: d.Pos()})
+	}
+	return b
+}
+
+// TryUintBits reads nBits bits as a uint64 from buffer
+func (d *D) TryUintBits(nBits int) (uint64, error) {
 	if nBits < 0 || nBits > 64 {
 		return 0, fmt.Errorf("nBits must be 0-64 (%d)", nBits)
 	}
-	// 64 bits max, 9 byte worse case if not byte aligned
-	buf := d.SharedReadBuf(9)
-	_, err := bitio.ReadFull(d.bitBuf, buf, int64(nBits)) // TODO: int64?
+	buf, err := d.TryBits(nBits)
 	if err != nil {
 		return 0, err
 	}
 
 	return bitio.Read64(buf[:], 0, int64(nBits)), nil // TODO: int64
 }
 
-// Bits reads nBits bits from buffer
-func (d *D) Bits(nBits int) uint64 {
-	n, err := d.TryBits(nBits)
+// UintBits reads nBits bits as uint64 from buffer
+func (d *D) UintBits(nBits int) uint64 {
+	n, err := d.TryUintBits(nBits)
 	if err != nil {
-		panic(IOError{Err: err, Op: "Bits", ReadSize: int64(nBits), Pos: d.Pos()})
+		panic(IOError{Err: err, Op: "UintBits", ReadSize: int64(nBits), Pos: d.Pos()})
 	}
 	return n
 }
 
-func (d *D) PeekBits(nBits int) uint64 {
+func (d *D) PeekUintBits(nBits int) uint64 {
 	n, err := d.TryPeekBits(nBits)
 	if err != nil {
-		panic(IOError{Err: err, Op: "PeekBits", ReadSize: int64(nBits), Pos: d.Pos()})
+		panic(IOError{Err: err, Op: "PeekUintBits", ReadSize: int64(nBits), Pos: d.Pos()})
 	}
 	return n
 }
@@ -450,7 +471,7 @@ func (d *D) TryPeekBits(nBits int) (uint64, error) {
 	if err != nil {
 		return 0, err
 	}
-	n, err := d.TryBits(nBits)
+	n, err := d.TryUintBits(nBits)
 	if _, err := d.bitBuf.SeekBits(start, io.SeekStart); err != nil {
 		return 0, err
 	}