升级流程引擎配置文件版本

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hoteas
2022-10-19 21:32:34 +08:00
parent cdba8af129
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// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package ocsp parses OCSP responses as specified in RFC 2560. OCSP responses
// are signed messages attesting to the validity of a certificate for a small
// period of time. This is used to manage revocation for X.509 certificates.
package ocsp // import "golang.org/x/crypto/ocsp"
import (
"crypto"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"crypto/rsa"
_ "crypto/sha1"
_ "crypto/sha256"
_ "crypto/sha512"
"crypto/x509"
"crypto/x509/pkix"
"encoding/asn1"
"errors"
"fmt"
"math/big"
"strconv"
"time"
)
var idPKIXOCSPBasic = asn1.ObjectIdentifier([]int{1, 3, 6, 1, 5, 5, 7, 48, 1, 1})
// ResponseStatus contains the result of an OCSP request. See
// https://tools.ietf.org/html/rfc6960#section-2.3
type ResponseStatus int
const (
Success ResponseStatus = 0
Malformed ResponseStatus = 1
InternalError ResponseStatus = 2
TryLater ResponseStatus = 3
// Status code four is unused in OCSP. See
// https://tools.ietf.org/html/rfc6960#section-4.2.1
SignatureRequired ResponseStatus = 5
Unauthorized ResponseStatus = 6
)
func (r ResponseStatus) String() string {
switch r {
case Success:
return "success"
case Malformed:
return "malformed"
case InternalError:
return "internal error"
case TryLater:
return "try later"
case SignatureRequired:
return "signature required"
case Unauthorized:
return "unauthorized"
default:
return "unknown OCSP status: " + strconv.Itoa(int(r))
}
}
// ResponseError is an error that may be returned by ParseResponse to indicate
// that the response itself is an error, not just that it's indicating that a
// certificate is revoked, unknown, etc.
type ResponseError struct {
Status ResponseStatus
}
func (r ResponseError) Error() string {
return "ocsp: error from server: " + r.Status.String()
}
// These are internal structures that reflect the ASN.1 structure of an OCSP
// response. See RFC 2560, section 4.2.
type certID struct {
HashAlgorithm pkix.AlgorithmIdentifier
NameHash []byte
IssuerKeyHash []byte
SerialNumber *big.Int
}
// https://tools.ietf.org/html/rfc2560#section-4.1.1
type ocspRequest struct {
TBSRequest tbsRequest
}
type tbsRequest struct {
Version int `asn1:"explicit,tag:0,default:0,optional"`
RequestorName pkix.RDNSequence `asn1:"explicit,tag:1,optional"`
RequestList []request
}
type request struct {
Cert certID
}
type responseASN1 struct {
Status asn1.Enumerated
Response responseBytes `asn1:"explicit,tag:0,optional"`
}
type responseBytes struct {
ResponseType asn1.ObjectIdentifier
Response []byte
}
type basicResponse struct {
TBSResponseData responseData
SignatureAlgorithm pkix.AlgorithmIdentifier
Signature asn1.BitString
Certificates []asn1.RawValue `asn1:"explicit,tag:0,optional"`
}
type responseData struct {
Raw asn1.RawContent
Version int `asn1:"optional,default:0,explicit,tag:0"`
RawResponderID asn1.RawValue
ProducedAt time.Time `asn1:"generalized"`
Responses []singleResponse
}
type singleResponse struct {
CertID certID
Good asn1.Flag `asn1:"tag:0,optional"`
Revoked revokedInfo `asn1:"tag:1,optional"`
Unknown asn1.Flag `asn1:"tag:2,optional"`
ThisUpdate time.Time `asn1:"generalized"`
NextUpdate time.Time `asn1:"generalized,explicit,tag:0,optional"`
SingleExtensions []pkix.Extension `asn1:"explicit,tag:1,optional"`
}
type revokedInfo struct {
RevocationTime time.Time `asn1:"generalized"`
Reason asn1.Enumerated `asn1:"explicit,tag:0,optional"`
}
var (
oidSignatureMD2WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 2}
oidSignatureMD5WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 4}
oidSignatureSHA1WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
oidSignatureSHA256WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 11}
oidSignatureSHA384WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 12}
oidSignatureSHA512WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 13}
oidSignatureDSAWithSHA1 = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 3}
oidSignatureDSAWithSHA256 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 3, 2}
oidSignatureECDSAWithSHA1 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 1}
oidSignatureECDSAWithSHA256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 2}
oidSignatureECDSAWithSHA384 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 3}
oidSignatureECDSAWithSHA512 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 4}
)
var hashOIDs = map[crypto.Hash]asn1.ObjectIdentifier{
crypto.SHA1: asn1.ObjectIdentifier([]int{1, 3, 14, 3, 2, 26}),
crypto.SHA256: asn1.ObjectIdentifier([]int{2, 16, 840, 1, 101, 3, 4, 2, 1}),
crypto.SHA384: asn1.ObjectIdentifier([]int{2, 16, 840, 1, 101, 3, 4, 2, 2}),
crypto.SHA512: asn1.ObjectIdentifier([]int{2, 16, 840, 1, 101, 3, 4, 2, 3}),
}
// TODO(rlb): This is also from crypto/x509, so same comment as AGL's below
var signatureAlgorithmDetails = []struct {
algo x509.SignatureAlgorithm
oid asn1.ObjectIdentifier
pubKeyAlgo x509.PublicKeyAlgorithm
hash crypto.Hash
}{
{x509.MD2WithRSA, oidSignatureMD2WithRSA, x509.RSA, crypto.Hash(0) /* no value for MD2 */},
{x509.MD5WithRSA, oidSignatureMD5WithRSA, x509.RSA, crypto.MD5},
{x509.SHA1WithRSA, oidSignatureSHA1WithRSA, x509.RSA, crypto.SHA1},
{x509.SHA256WithRSA, oidSignatureSHA256WithRSA, x509.RSA, crypto.SHA256},
{x509.SHA384WithRSA, oidSignatureSHA384WithRSA, x509.RSA, crypto.SHA384},
{x509.SHA512WithRSA, oidSignatureSHA512WithRSA, x509.RSA, crypto.SHA512},
{x509.DSAWithSHA1, oidSignatureDSAWithSHA1, x509.DSA, crypto.SHA1},
{x509.DSAWithSHA256, oidSignatureDSAWithSHA256, x509.DSA, crypto.SHA256},
{x509.ECDSAWithSHA1, oidSignatureECDSAWithSHA1, x509.ECDSA, crypto.SHA1},
{x509.ECDSAWithSHA256, oidSignatureECDSAWithSHA256, x509.ECDSA, crypto.SHA256},
{x509.ECDSAWithSHA384, oidSignatureECDSAWithSHA384, x509.ECDSA, crypto.SHA384},
{x509.ECDSAWithSHA512, oidSignatureECDSAWithSHA512, x509.ECDSA, crypto.SHA512},
}
// TODO(rlb): This is also from crypto/x509, so same comment as AGL's below
func signingParamsForPublicKey(pub interface{}, requestedSigAlgo x509.SignatureAlgorithm) (hashFunc crypto.Hash, sigAlgo pkix.AlgorithmIdentifier, err error) {
var pubType x509.PublicKeyAlgorithm
switch pub := pub.(type) {
case *rsa.PublicKey:
pubType = x509.RSA
hashFunc = crypto.SHA256
sigAlgo.Algorithm = oidSignatureSHA256WithRSA
sigAlgo.Parameters = asn1.RawValue{
Tag: 5,
}
case *ecdsa.PublicKey:
pubType = x509.ECDSA
switch pub.Curve {
case elliptic.P224(), elliptic.P256():
hashFunc = crypto.SHA256
sigAlgo.Algorithm = oidSignatureECDSAWithSHA256
case elliptic.P384():
hashFunc = crypto.SHA384
sigAlgo.Algorithm = oidSignatureECDSAWithSHA384
case elliptic.P521():
hashFunc = crypto.SHA512
sigAlgo.Algorithm = oidSignatureECDSAWithSHA512
default:
err = errors.New("x509: unknown elliptic curve")
}
default:
err = errors.New("x509: only RSA and ECDSA keys supported")
}
if err != nil {
return
}
if requestedSigAlgo == 0 {
return
}
found := false
for _, details := range signatureAlgorithmDetails {
if details.algo == requestedSigAlgo {
if details.pubKeyAlgo != pubType {
err = errors.New("x509: requested SignatureAlgorithm does not match private key type")
return
}
sigAlgo.Algorithm, hashFunc = details.oid, details.hash
if hashFunc == 0 {
err = errors.New("x509: cannot sign with hash function requested")
return
}
found = true
break
}
}
if !found {
err = errors.New("x509: unknown SignatureAlgorithm")
}
return
}
// TODO(agl): this is taken from crypto/x509 and so should probably be exported
// from crypto/x509 or crypto/x509/pkix.
func getSignatureAlgorithmFromOID(oid asn1.ObjectIdentifier) x509.SignatureAlgorithm {
for _, details := range signatureAlgorithmDetails {
if oid.Equal(details.oid) {
return details.algo
}
}
return x509.UnknownSignatureAlgorithm
}
// TODO(rlb): This is not taken from crypto/x509, but it's of the same general form.
func getHashAlgorithmFromOID(target asn1.ObjectIdentifier) crypto.Hash {
for hash, oid := range hashOIDs {
if oid.Equal(target) {
return hash
}
}
return crypto.Hash(0)
}
func getOIDFromHashAlgorithm(target crypto.Hash) asn1.ObjectIdentifier {
for hash, oid := range hashOIDs {
if hash == target {
return oid
}
}
return nil
}
// This is the exposed reflection of the internal OCSP structures.
// The status values that can be expressed in OCSP. See RFC 6960.
const (
// Good means that the certificate is valid.
Good = iota
// Revoked means that the certificate has been deliberately revoked.
Revoked
// Unknown means that the OCSP responder doesn't know about the certificate.
Unknown
// ServerFailed is unused and was never used (see
// https://go-review.googlesource.com/#/c/18944). ParseResponse will
// return a ResponseError when an error response is parsed.
ServerFailed
)
// The enumerated reasons for revoking a certificate. See RFC 5280.
const (
Unspecified = 0
KeyCompromise = 1
CACompromise = 2
AffiliationChanged = 3
Superseded = 4
CessationOfOperation = 5
CertificateHold = 6
RemoveFromCRL = 8
PrivilegeWithdrawn = 9
AACompromise = 10
)
// Request represents an OCSP request. See RFC 6960.
type Request struct {
HashAlgorithm crypto.Hash
IssuerNameHash []byte
IssuerKeyHash []byte
SerialNumber *big.Int
}
// Marshal marshals the OCSP request to ASN.1 DER encoded form.
func (req *Request) Marshal() ([]byte, error) {
hashAlg := getOIDFromHashAlgorithm(req.HashAlgorithm)
if hashAlg == nil {
return nil, errors.New("Unknown hash algorithm")
}
return asn1.Marshal(ocspRequest{
tbsRequest{
Version: 0,
RequestList: []request{
{
Cert: certID{
pkix.AlgorithmIdentifier{
Algorithm: hashAlg,
Parameters: asn1.RawValue{Tag: 5 /* ASN.1 NULL */},
},
req.IssuerNameHash,
req.IssuerKeyHash,
req.SerialNumber,
},
},
},
},
})
}
// Response represents an OCSP response containing a single SingleResponse. See
// RFC 6960.
type Response struct {
Raw []byte
// Status is one of {Good, Revoked, Unknown}
Status int
SerialNumber *big.Int
ProducedAt, ThisUpdate, NextUpdate, RevokedAt time.Time
RevocationReason int
Certificate *x509.Certificate
// TBSResponseData contains the raw bytes of the signed response. If
// Certificate is nil then this can be used to verify Signature.
TBSResponseData []byte
Signature []byte
SignatureAlgorithm x509.SignatureAlgorithm
// IssuerHash is the hash used to compute the IssuerNameHash and IssuerKeyHash.
// Valid values are crypto.SHA1, crypto.SHA256, crypto.SHA384, and crypto.SHA512.
// If zero, the default is crypto.SHA1.
IssuerHash crypto.Hash
// RawResponderName optionally contains the DER-encoded subject of the
// responder certificate. Exactly one of RawResponderName and
// ResponderKeyHash is set.
RawResponderName []byte
// ResponderKeyHash optionally contains the SHA-1 hash of the
// responder's public key. Exactly one of RawResponderName and
// ResponderKeyHash is set.
ResponderKeyHash []byte
// Extensions contains raw X.509 extensions from the singleExtensions field
// of the OCSP response. When parsing certificates, this can be used to
// extract non-critical extensions that are not parsed by this package. When
// marshaling OCSP responses, the Extensions field is ignored, see
// ExtraExtensions.
Extensions []pkix.Extension
// ExtraExtensions contains extensions to be copied, raw, into any marshaled
// OCSP response (in the singleExtensions field). Values override any
// extensions that would otherwise be produced based on the other fields. The
// ExtraExtensions field is not populated when parsing certificates, see
// Extensions.
ExtraExtensions []pkix.Extension
}
// These are pre-serialized error responses for the various non-success codes
// defined by OCSP. The Unauthorized code in particular can be used by an OCSP
// responder that supports only pre-signed responses as a response to requests
// for certificates with unknown status. See RFC 5019.
var (
MalformedRequestErrorResponse = []byte{0x30, 0x03, 0x0A, 0x01, 0x01}
InternalErrorErrorResponse = []byte{0x30, 0x03, 0x0A, 0x01, 0x02}
TryLaterErrorResponse = []byte{0x30, 0x03, 0x0A, 0x01, 0x03}
SigRequredErrorResponse = []byte{0x30, 0x03, 0x0A, 0x01, 0x05}
UnauthorizedErrorResponse = []byte{0x30, 0x03, 0x0A, 0x01, 0x06}
)
// CheckSignatureFrom checks that the signature in resp is a valid signature
// from issuer. This should only be used if resp.Certificate is nil. Otherwise,
// the OCSP response contained an intermediate certificate that created the
// signature. That signature is checked by ParseResponse and only
// resp.Certificate remains to be validated.
func (resp *Response) CheckSignatureFrom(issuer *x509.Certificate) error {
return issuer.CheckSignature(resp.SignatureAlgorithm, resp.TBSResponseData, resp.Signature)
}
// ParseError results from an invalid OCSP response.
type ParseError string
func (p ParseError) Error() string {
return string(p)
}
// ParseRequest parses an OCSP request in DER form. It only supports
// requests for a single certificate. Signed requests are not supported.
// If a request includes a signature, it will result in a ParseError.
func ParseRequest(bytes []byte) (*Request, error) {
var req ocspRequest
rest, err := asn1.Unmarshal(bytes, &req)
if err != nil {
return nil, err
}
if len(rest) > 0 {
return nil, ParseError("trailing data in OCSP request")
}
if len(req.TBSRequest.RequestList) == 0 {
return nil, ParseError("OCSP request contains no request body")
}
innerRequest := req.TBSRequest.RequestList[0]
hashFunc := getHashAlgorithmFromOID(innerRequest.Cert.HashAlgorithm.Algorithm)
if hashFunc == crypto.Hash(0) {
return nil, ParseError("OCSP request uses unknown hash function")
}
return &Request{
HashAlgorithm: hashFunc,
IssuerNameHash: innerRequest.Cert.NameHash,
IssuerKeyHash: innerRequest.Cert.IssuerKeyHash,
SerialNumber: innerRequest.Cert.SerialNumber,
}, nil
}
// ParseResponse parses an OCSP response in DER form. The response must contain
// only one certificate status. To parse the status of a specific certificate
// from a response which may contain multiple statuses, use ParseResponseForCert
// instead.
//
// If the response contains an embedded certificate, then that certificate will
// be used to verify the response signature. If the response contains an
// embedded certificate and issuer is not nil, then issuer will be used to verify
// the signature on the embedded certificate.
//
// If the response does not contain an embedded certificate and issuer is not
// nil, then issuer will be used to verify the response signature.
//
// Invalid responses and parse failures will result in a ParseError.
// Error responses will result in a ResponseError.
func ParseResponse(bytes []byte, issuer *x509.Certificate) (*Response, error) {
return ParseResponseForCert(bytes, nil, issuer)
}
// ParseResponseForCert acts identically to ParseResponse, except it supports
// parsing responses that contain multiple statuses. If the response contains
// multiple statuses and cert is not nil, then ParseResponseForCert will return
// the first status which contains a matching serial, otherwise it will return an
// error. If cert is nil, then the first status in the response will be returned.
func ParseResponseForCert(bytes []byte, cert, issuer *x509.Certificate) (*Response, error) {
var resp responseASN1
rest, err := asn1.Unmarshal(bytes, &resp)
if err != nil {
return nil, err
}
if len(rest) > 0 {
return nil, ParseError("trailing data in OCSP response")
}
if status := ResponseStatus(resp.Status); status != Success {
return nil, ResponseError{status}
}
if !resp.Response.ResponseType.Equal(idPKIXOCSPBasic) {
return nil, ParseError("bad OCSP response type")
}
var basicResp basicResponse
rest, err = asn1.Unmarshal(resp.Response.Response, &basicResp)
if err != nil {
return nil, err
}
if len(rest) > 0 {
return nil, ParseError("trailing data in OCSP response")
}
if n := len(basicResp.TBSResponseData.Responses); n == 0 || cert == nil && n > 1 {
return nil, ParseError("OCSP response contains bad number of responses")
}
var singleResp singleResponse
if cert == nil {
singleResp = basicResp.TBSResponseData.Responses[0]
} else {
match := false
for _, resp := range basicResp.TBSResponseData.Responses {
if cert.SerialNumber.Cmp(resp.CertID.SerialNumber) == 0 {
singleResp = resp
match = true
break
}
}
if !match {
return nil, ParseError("no response matching the supplied certificate")
}
}
ret := &Response{
Raw: bytes,
TBSResponseData: basicResp.TBSResponseData.Raw,
Signature: basicResp.Signature.RightAlign(),
SignatureAlgorithm: getSignatureAlgorithmFromOID(basicResp.SignatureAlgorithm.Algorithm),
Extensions: singleResp.SingleExtensions,
SerialNumber: singleResp.CertID.SerialNumber,
ProducedAt: basicResp.TBSResponseData.ProducedAt,
ThisUpdate: singleResp.ThisUpdate,
NextUpdate: singleResp.NextUpdate,
}
// Handle the ResponderID CHOICE tag. ResponderID can be flattened into
// TBSResponseData once https://go-review.googlesource.com/34503 has been
// released.
rawResponderID := basicResp.TBSResponseData.RawResponderID
switch rawResponderID.Tag {
case 1: // Name
var rdn pkix.RDNSequence
if rest, err := asn1.Unmarshal(rawResponderID.Bytes, &rdn); err != nil || len(rest) != 0 {
return nil, ParseError("invalid responder name")
}
ret.RawResponderName = rawResponderID.Bytes
case 2: // KeyHash
if rest, err := asn1.Unmarshal(rawResponderID.Bytes, &ret.ResponderKeyHash); err != nil || len(rest) != 0 {
return nil, ParseError("invalid responder key hash")
}
default:
return nil, ParseError("invalid responder id tag")
}
if len(basicResp.Certificates) > 0 {
// Responders should only send a single certificate (if they
// send any) that connects the responder's certificate to the
// original issuer. We accept responses with multiple
// certificates due to a number responders sending them[1], but
// ignore all but the first.
//
// [1] https://github.com/golang/go/issues/21527
ret.Certificate, err = x509.ParseCertificate(basicResp.Certificates[0].FullBytes)
if err != nil {
return nil, err
}
if err := ret.CheckSignatureFrom(ret.Certificate); err != nil {
return nil, ParseError("bad signature on embedded certificate: " + err.Error())
}
if issuer != nil {
if err := issuer.CheckSignature(ret.Certificate.SignatureAlgorithm, ret.Certificate.RawTBSCertificate, ret.Certificate.Signature); err != nil {
return nil, ParseError("bad OCSP signature: " + err.Error())
}
}
} else if issuer != nil {
if err := ret.CheckSignatureFrom(issuer); err != nil {
return nil, ParseError("bad OCSP signature: " + err.Error())
}
}
for _, ext := range singleResp.SingleExtensions {
if ext.Critical {
return nil, ParseError("unsupported critical extension")
}
}
for h, oid := range hashOIDs {
if singleResp.CertID.HashAlgorithm.Algorithm.Equal(oid) {
ret.IssuerHash = h
break
}
}
if ret.IssuerHash == 0 {
return nil, ParseError("unsupported issuer hash algorithm")
}
switch {
case bool(singleResp.Good):
ret.Status = Good
case bool(singleResp.Unknown):
ret.Status = Unknown
default:
ret.Status = Revoked
ret.RevokedAt = singleResp.Revoked.RevocationTime
ret.RevocationReason = int(singleResp.Revoked.Reason)
}
return ret, nil
}
// RequestOptions contains options for constructing OCSP requests.
type RequestOptions struct {
// Hash contains the hash function that should be used when
// constructing the OCSP request. If zero, SHA-1 will be used.
Hash crypto.Hash
}
func (opts *RequestOptions) hash() crypto.Hash {
if opts == nil || opts.Hash == 0 {
// SHA-1 is nearly universally used in OCSP.
return crypto.SHA1
}
return opts.Hash
}
// CreateRequest returns a DER-encoded, OCSP request for the status of cert. If
// opts is nil then sensible defaults are used.
func CreateRequest(cert, issuer *x509.Certificate, opts *RequestOptions) ([]byte, error) {
hashFunc := opts.hash()
// OCSP seems to be the only place where these raw hash identifiers are
// used. I took the following from
// http://msdn.microsoft.com/en-us/library/ff635603.aspx
_, ok := hashOIDs[hashFunc]
if !ok {
return nil, x509.ErrUnsupportedAlgorithm
}
if !hashFunc.Available() {
return nil, x509.ErrUnsupportedAlgorithm
}
h := opts.hash().New()
var publicKeyInfo struct {
Algorithm pkix.AlgorithmIdentifier
PublicKey asn1.BitString
}
if _, err := asn1.Unmarshal(issuer.RawSubjectPublicKeyInfo, &publicKeyInfo); err != nil {
return nil, err
}
h.Write(publicKeyInfo.PublicKey.RightAlign())
issuerKeyHash := h.Sum(nil)
h.Reset()
h.Write(issuer.RawSubject)
issuerNameHash := h.Sum(nil)
req := &Request{
HashAlgorithm: hashFunc,
IssuerNameHash: issuerNameHash,
IssuerKeyHash: issuerKeyHash,
SerialNumber: cert.SerialNumber,
}
return req.Marshal()
}
// CreateResponse returns a DER-encoded OCSP response with the specified contents.
// The fields in the response are populated as follows:
//
// The responder cert is used to populate the responder's name field, and the
// certificate itself is provided alongside the OCSP response signature.
//
// The issuer cert is used to populate the IssuerNameHash and IssuerKeyHash fields.
//
// The template is used to populate the SerialNumber, Status, RevokedAt,
// RevocationReason, ThisUpdate, and NextUpdate fields.
//
// If template.IssuerHash is not set, SHA1 will be used.
//
// The ProducedAt date is automatically set to the current date, to the nearest minute.
func CreateResponse(issuer, responderCert *x509.Certificate, template Response, priv crypto.Signer) ([]byte, error) {
var publicKeyInfo struct {
Algorithm pkix.AlgorithmIdentifier
PublicKey asn1.BitString
}
if _, err := asn1.Unmarshal(issuer.RawSubjectPublicKeyInfo, &publicKeyInfo); err != nil {
return nil, err
}
if template.IssuerHash == 0 {
template.IssuerHash = crypto.SHA1
}
hashOID := getOIDFromHashAlgorithm(template.IssuerHash)
if hashOID == nil {
return nil, errors.New("unsupported issuer hash algorithm")
}
if !template.IssuerHash.Available() {
return nil, fmt.Errorf("issuer hash algorithm %v not linked into binary", template.IssuerHash)
}
h := template.IssuerHash.New()
h.Write(publicKeyInfo.PublicKey.RightAlign())
issuerKeyHash := h.Sum(nil)
h.Reset()
h.Write(issuer.RawSubject)
issuerNameHash := h.Sum(nil)
innerResponse := singleResponse{
CertID: certID{
HashAlgorithm: pkix.AlgorithmIdentifier{
Algorithm: hashOID,
Parameters: asn1.RawValue{Tag: 5 /* ASN.1 NULL */},
},
NameHash: issuerNameHash,
IssuerKeyHash: issuerKeyHash,
SerialNumber: template.SerialNumber,
},
ThisUpdate: template.ThisUpdate.UTC(),
NextUpdate: template.NextUpdate.UTC(),
SingleExtensions: template.ExtraExtensions,
}
switch template.Status {
case Good:
innerResponse.Good = true
case Unknown:
innerResponse.Unknown = true
case Revoked:
innerResponse.Revoked = revokedInfo{
RevocationTime: template.RevokedAt.UTC(),
Reason: asn1.Enumerated(template.RevocationReason),
}
}
rawResponderID := asn1.RawValue{
Class: 2, // context-specific
Tag: 1, // Name (explicit tag)
IsCompound: true,
Bytes: responderCert.RawSubject,
}
tbsResponseData := responseData{
Version: 0,
RawResponderID: rawResponderID,
ProducedAt: time.Now().Truncate(time.Minute).UTC(),
Responses: []singleResponse{innerResponse},
}
tbsResponseDataDER, err := asn1.Marshal(tbsResponseData)
if err != nil {
return nil, err
}
hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(priv.Public(), template.SignatureAlgorithm)
if err != nil {
return nil, err
}
responseHash := hashFunc.New()
responseHash.Write(tbsResponseDataDER)
signature, err := priv.Sign(rand.Reader, responseHash.Sum(nil), hashFunc)
if err != nil {
return nil, err
}
response := basicResponse{
TBSResponseData: tbsResponseData,
SignatureAlgorithm: signatureAlgorithm,
Signature: asn1.BitString{
Bytes: signature,
BitLength: 8 * len(signature),
},
}
if template.Certificate != nil {
response.Certificates = []asn1.RawValue{
{FullBytes: template.Certificate.Raw},
}
}
responseDER, err := asn1.Marshal(response)
if err != nil {
return nil, err
}
return asn1.Marshal(responseASN1{
Status: asn1.Enumerated(Success),
Response: responseBytes{
ResponseType: idPKIXOCSPBasic,
Response: responseDER,
},
})
}
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// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
/*
Package pbkdf2 implements the key derivation function PBKDF2 as defined in RFC
2898 / PKCS #5 v2.0.
A key derivation function is useful when encrypting data based on a password
or any other not-fully-random data. It uses a pseudorandom function to derive
a secure encryption key based on the password.
While v2.0 of the standard defines only one pseudorandom function to use,
HMAC-SHA1, the drafted v2.1 specification allows use of all five FIPS Approved
Hash Functions SHA-1, SHA-224, SHA-256, SHA-384 and SHA-512 for HMAC. To
choose, you can pass the `New` functions from the different SHA packages to
pbkdf2.Key.
*/
package pbkdf2 // import "golang.org/x/crypto/pbkdf2"
import (
"crypto/hmac"
"hash"
)
// Key derives a key from the password, salt and iteration count, returning a
// []byte of length keylen that can be used as cryptographic key. The key is
// derived based on the method described as PBKDF2 with the HMAC variant using
// the supplied hash function.
//
// For example, to use a HMAC-SHA-1 based PBKDF2 key derivation function, you
// can get a derived key for e.g. AES-256 (which needs a 32-byte key) by
// doing:
//
// dk := pbkdf2.Key([]byte("some password"), salt, 4096, 32, sha1.New)
//
// Remember to get a good random salt. At least 8 bytes is recommended by the
// RFC.
//
// Using a higher iteration count will increase the cost of an exhaustive
// search but will also make derivation proportionally slower.
func Key(password, salt []byte, iter, keyLen int, h func() hash.Hash) []byte {
prf := hmac.New(h, password)
hashLen := prf.Size()
numBlocks := (keyLen + hashLen - 1) / hashLen
var buf [4]byte
dk := make([]byte, 0, numBlocks*hashLen)
U := make([]byte, hashLen)
for block := 1; block <= numBlocks; block++ {
// N.B.: || means concatenation, ^ means XOR
// for each block T_i = U_1 ^ U_2 ^ ... ^ U_iter
// U_1 = PRF(password, salt || uint(i))
prf.Reset()
prf.Write(salt)
buf[0] = byte(block >> 24)
buf[1] = byte(block >> 16)
buf[2] = byte(block >> 8)
buf[3] = byte(block)
prf.Write(buf[:4])
dk = prf.Sum(dk)
T := dk[len(dk)-hashLen:]
copy(U, T)
// U_n = PRF(password, U_(n-1))
for n := 2; n <= iter; n++ {
prf.Reset()
prf.Write(U)
U = U[:0]
U = prf.Sum(U)
for x := range U {
T[x] ^= U[x]
}
}
}
return dk[:keyLen]
}
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# This source code refers to The Go Authors for copyright purposes.
# The master list of authors is in the main Go distribution,
# visible at http://tip.golang.org/AUTHORS.
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# This source code was written by the Go contributors.
# The master list of contributors is in the main Go distribution,
# visible at http://tip.golang.org/CONTRIBUTORS.
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Copyright (c) 2009 The Go Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+22
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@@ -0,0 +1,22 @@
Additional IP Rights Grant (Patents)
"This implementation" means the copyrightable works distributed by
Google as part of the Go project.
Google hereby grants to You a perpetual, worldwide, non-exclusive,
no-charge, royalty-free, irrevocable (except as stated in this section)
patent license to make, have made, use, offer to sell, sell, import,
transfer and otherwise run, modify and propagate the contents of this
implementation of Go, where such license applies only to those patent
claims, both currently owned or controlled by Google and acquired in
the future, licensable by Google that are necessarily infringed by this
implementation of Go. This grant does not include claims that would be
infringed only as a consequence of further modification of this
implementation. If you or your agent or exclusive licensee institute or
order or agree to the institution of patent litigation against any
entity (including a cross-claim or counterclaim in a lawsuit) alleging
that this implementation of Go or any code incorporated within this
implementation of Go constitutes direct or contributory patent
infringement, or inducement of patent infringement, then any patent
rights granted to you under this License for this implementation of Go
shall terminate as of the date such litigation is filed.
+66
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// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package errgroup provides synchronization, error propagation, and Context
// cancelation for groups of goroutines working on subtasks of a common task.
package errgroup
import (
"context"
"sync"
)
// A Group is a collection of goroutines working on subtasks that are part of
// the same overall task.
//
// A zero Group is valid and does not cancel on error.
type Group struct {
cancel func()
wg sync.WaitGroup
errOnce sync.Once
err error
}
// WithContext returns a new Group and an associated Context derived from ctx.
//
// The derived Context is canceled the first time a function passed to Go
// returns a non-nil error or the first time Wait returns, whichever occurs
// first.
func WithContext(ctx context.Context) (*Group, context.Context) {
ctx, cancel := context.WithCancel(ctx)
return &Group{cancel: cancel}, ctx
}
// Wait blocks until all function calls from the Go method have returned, then
// returns the first non-nil error (if any) from them.
func (g *Group) Wait() error {
g.wg.Wait()
if g.cancel != nil {
g.cancel()
}
return g.err
}
// Go calls the given function in a new goroutine.
//
// The first call to return a non-nil error cancels the group; its error will be
// returned by Wait.
func (g *Group) Go(f func() error) {
g.wg.Add(1)
go func() {
defer g.wg.Done()
if err := f(); err != nil {
g.errOnce.Do(func() {
g.err = err
if g.cancel != nil {
g.cancel()
}
})
}
}()
}
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# This source code refers to The Go Authors for copyright purposes.
# The master list of authors is in the main Go distribution,
# visible at http://tip.golang.org/AUTHORS.
+3
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# This source code was written by the Go contributors.
# The master list of contributors is in the main Go distribution,
# visible at http://tip.golang.org/CONTRIBUTORS.
+27
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Copyright (c) 2009 The Go Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+22
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@@ -0,0 +1,22 @@
Additional IP Rights Grant (Patents)
"This implementation" means the copyrightable works distributed by
Google as part of the Go project.
Google hereby grants to You a perpetual, worldwide, non-exclusive,
no-charge, royalty-free, irrevocable (except as stated in this section)
patent license to make, have made, use, offer to sell, sell, import,
transfer and otherwise run, modify and propagate the contents of this
implementation of Go, where such license applies only to those patent
claims, both currently owned or controlled by Google and acquired in
the future, licensable by Google that are necessarily infringed by this
implementation of Go. This grant does not include claims that would be
infringed only as a consequence of further modification of this
implementation. If you or your agent or exclusive licensee institute or
order or agree to the institution of patent litigation against any
entity (including a cross-claim or counterclaim in a lawsuit) alleging
that this implementation of Go or any code incorporated within this
implementation of Go constitutes direct or contributory patent
infringement, or inducement of patent infringement, then any patent
rights granted to you under this License for this implementation of Go
shall terminate as of the date such litigation is filed.
+709
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// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package transform provides reader and writer wrappers that transform the
// bytes passing through as well as various transformations. Example
// transformations provided by other packages include normalization and
// conversion between character sets.
package transform // import "golang.org/x/text/transform"
import (
"bytes"
"errors"
"io"
"unicode/utf8"
)
var (
// ErrShortDst means that the destination buffer was too short to
// receive all of the transformed bytes.
ErrShortDst = errors.New("transform: short destination buffer")
// ErrShortSrc means that the source buffer has insufficient data to
// complete the transformation.
ErrShortSrc = errors.New("transform: short source buffer")
// ErrEndOfSpan means that the input and output (the transformed input)
// are not identical.
ErrEndOfSpan = errors.New("transform: input and output are not identical")
// errInconsistentByteCount means that Transform returned success (nil
// error) but also returned nSrc inconsistent with the src argument.
errInconsistentByteCount = errors.New("transform: inconsistent byte count returned")
// errShortInternal means that an internal buffer is not large enough
// to make progress and the Transform operation must be aborted.
errShortInternal = errors.New("transform: short internal buffer")
)
// Transformer transforms bytes.
type Transformer interface {
// Transform writes to dst the transformed bytes read from src, and
// returns the number of dst bytes written and src bytes read. The
// atEOF argument tells whether src represents the last bytes of the
// input.
//
// Callers should always process the nDst bytes produced and account
// for the nSrc bytes consumed before considering the error err.
//
// A nil error means that all of the transformed bytes (whether freshly
// transformed from src or left over from previous Transform calls)
// were written to dst. A nil error can be returned regardless of
// whether atEOF is true. If err is nil then nSrc must equal len(src);
// the converse is not necessarily true.
//
// ErrShortDst means that dst was too short to receive all of the
// transformed bytes. ErrShortSrc means that src had insufficient data
// to complete the transformation. If both conditions apply, then
// either error may be returned. Other than the error conditions listed
// here, implementations are free to report other errors that arise.
Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error)
// Reset resets the state and allows a Transformer to be reused.
Reset()
}
// SpanningTransformer extends the Transformer interface with a Span method
// that determines how much of the input already conforms to the Transformer.
type SpanningTransformer interface {
Transformer
// Span returns a position in src such that transforming src[:n] results in
// identical output src[:n] for these bytes. It does not necessarily return
// the largest such n. The atEOF argument tells whether src represents the
// last bytes of the input.
//
// Callers should always account for the n bytes consumed before
// considering the error err.
//
// A nil error means that all input bytes are known to be identical to the
// output produced by the Transformer. A nil error can be returned
// regardless of whether atEOF is true. If err is nil, then n must
// equal len(src); the converse is not necessarily true.
//
// ErrEndOfSpan means that the Transformer output may differ from the
// input after n bytes. Note that n may be len(src), meaning that the output
// would contain additional bytes after otherwise identical output.
// ErrShortSrc means that src had insufficient data to determine whether the
// remaining bytes would change. Other than the error conditions listed
// here, implementations are free to report other errors that arise.
//
// Calling Span can modify the Transformer state as a side effect. In
// effect, it does the transformation just as calling Transform would, only
// without copying to a destination buffer and only up to a point it can
// determine the input and output bytes are the same. This is obviously more
// limited than calling Transform, but can be more efficient in terms of
// copying and allocating buffers. Calls to Span and Transform may be
// interleaved.
Span(src []byte, atEOF bool) (n int, err error)
}
// NopResetter can be embedded by implementations of Transformer to add a nop
// Reset method.
type NopResetter struct{}
// Reset implements the Reset method of the Transformer interface.
func (NopResetter) Reset() {}
// Reader wraps another io.Reader by transforming the bytes read.
type Reader struct {
r io.Reader
t Transformer
err error
// dst[dst0:dst1] contains bytes that have been transformed by t but
// not yet copied out via Read.
dst []byte
dst0, dst1 int
// src[src0:src1] contains bytes that have been read from r but not
// yet transformed through t.
src []byte
src0, src1 int
// transformComplete is whether the transformation is complete,
// regardless of whether or not it was successful.
transformComplete bool
}
const defaultBufSize = 4096
// NewReader returns a new Reader that wraps r by transforming the bytes read
// via t. It calls Reset on t.
func NewReader(r io.Reader, t Transformer) *Reader {
t.Reset()
return &Reader{
r: r,
t: t,
dst: make([]byte, defaultBufSize),
src: make([]byte, defaultBufSize),
}
}
// Read implements the io.Reader interface.
func (r *Reader) Read(p []byte) (int, error) {
n, err := 0, error(nil)
for {
// Copy out any transformed bytes and return the final error if we are done.
if r.dst0 != r.dst1 {
n = copy(p, r.dst[r.dst0:r.dst1])
r.dst0 += n
if r.dst0 == r.dst1 && r.transformComplete {
return n, r.err
}
return n, nil
} else if r.transformComplete {
return 0, r.err
}
// Try to transform some source bytes, or to flush the transformer if we
// are out of source bytes. We do this even if r.r.Read returned an error.
// As the io.Reader documentation says, "process the n > 0 bytes returned
// before considering the error".
if r.src0 != r.src1 || r.err != nil {
r.dst0 = 0
r.dst1, n, err = r.t.Transform(r.dst, r.src[r.src0:r.src1], r.err == io.EOF)
r.src0 += n
switch {
case err == nil:
if r.src0 != r.src1 {
r.err = errInconsistentByteCount
}
// The Transform call was successful; we are complete if we
// cannot read more bytes into src.
r.transformComplete = r.err != nil
continue
case err == ErrShortDst && (r.dst1 != 0 || n != 0):
// Make room in dst by copying out, and try again.
continue
case err == ErrShortSrc && r.src1-r.src0 != len(r.src) && r.err == nil:
// Read more bytes into src via the code below, and try again.
default:
r.transformComplete = true
// The reader error (r.err) takes precedence over the
// transformer error (err) unless r.err is nil or io.EOF.
if r.err == nil || r.err == io.EOF {
r.err = err
}
continue
}
}
// Move any untransformed source bytes to the start of the buffer
// and read more bytes.
if r.src0 != 0 {
r.src0, r.src1 = 0, copy(r.src, r.src[r.src0:r.src1])
}
n, r.err = r.r.Read(r.src[r.src1:])
r.src1 += n
}
}
// TODO: implement ReadByte (and ReadRune??).
// Writer wraps another io.Writer by transforming the bytes read.
// The user needs to call Close to flush unwritten bytes that may
// be buffered.
type Writer struct {
w io.Writer
t Transformer
dst []byte
// src[:n] contains bytes that have not yet passed through t.
src []byte
n int
}
// NewWriter returns a new Writer that wraps w by transforming the bytes written
// via t. It calls Reset on t.
func NewWriter(w io.Writer, t Transformer) *Writer {
t.Reset()
return &Writer{
w: w,
t: t,
dst: make([]byte, defaultBufSize),
src: make([]byte, defaultBufSize),
}
}
// Write implements the io.Writer interface. If there are not enough
// bytes available to complete a Transform, the bytes will be buffered
// for the next write. Call Close to convert the remaining bytes.
func (w *Writer) Write(data []byte) (n int, err error) {
src := data
if w.n > 0 {
// Append bytes from data to the last remainder.
// TODO: limit the amount copied on first try.
n = copy(w.src[w.n:], data)
w.n += n
src = w.src[:w.n]
}
for {
nDst, nSrc, err := w.t.Transform(w.dst, src, false)
if _, werr := w.w.Write(w.dst[:nDst]); werr != nil {
return n, werr
}
src = src[nSrc:]
if w.n == 0 {
n += nSrc
} else if len(src) <= n {
// Enough bytes from w.src have been consumed. We make src point
// to data instead to reduce the copying.
w.n = 0
n -= len(src)
src = data[n:]
if n < len(data) && (err == nil || err == ErrShortSrc) {
continue
}
}
switch err {
case ErrShortDst:
// This error is okay as long as we are making progress.
if nDst > 0 || nSrc > 0 {
continue
}
case ErrShortSrc:
if len(src) < len(w.src) {
m := copy(w.src, src)
// If w.n > 0, bytes from data were already copied to w.src and n
// was already set to the number of bytes consumed.
if w.n == 0 {
n += m
}
w.n = m
err = nil
} else if nDst > 0 || nSrc > 0 {
// Not enough buffer to store the remainder. Keep processing as
// long as there is progress. Without this case, transforms that
// require a lookahead larger than the buffer may result in an
// error. This is not something one may expect to be common in
// practice, but it may occur when buffers are set to small
// sizes during testing.
continue
}
case nil:
if w.n > 0 {
err = errInconsistentByteCount
}
}
return n, err
}
}
// Close implements the io.Closer interface.
func (w *Writer) Close() error {
src := w.src[:w.n]
for {
nDst, nSrc, err := w.t.Transform(w.dst, src, true)
if _, werr := w.w.Write(w.dst[:nDst]); werr != nil {
return werr
}
if err != ErrShortDst {
return err
}
src = src[nSrc:]
}
}
type nop struct{ NopResetter }
func (nop) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
n := copy(dst, src)
if n < len(src) {
err = ErrShortDst
}
return n, n, err
}
func (nop) Span(src []byte, atEOF bool) (n int, err error) {
return len(src), nil
}
type discard struct{ NopResetter }
func (discard) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
return 0, len(src), nil
}
var (
// Discard is a Transformer for which all Transform calls succeed
// by consuming all bytes and writing nothing.
Discard Transformer = discard{}
// Nop is a SpanningTransformer that copies src to dst.
Nop SpanningTransformer = nop{}
)
// chain is a sequence of links. A chain with N Transformers has N+1 links and
// N+1 buffers. Of those N+1 buffers, the first and last are the src and dst
// buffers given to chain.Transform and the middle N-1 buffers are intermediate
// buffers owned by the chain. The i'th link transforms bytes from the i'th
// buffer chain.link[i].b at read offset chain.link[i].p to the i+1'th buffer
// chain.link[i+1].b at write offset chain.link[i+1].n, for i in [0, N).
type chain struct {
link []link
err error
// errStart is the index at which the error occurred plus 1. Processing
// errStart at this level at the next call to Transform. As long as
// errStart > 0, chain will not consume any more source bytes.
errStart int
}
func (c *chain) fatalError(errIndex int, err error) {
if i := errIndex + 1; i > c.errStart {
c.errStart = i
c.err = err
}
}
type link struct {
t Transformer
// b[p:n] holds the bytes to be transformed by t.
b []byte
p int
n int
}
func (l *link) src() []byte {
return l.b[l.p:l.n]
}
func (l *link) dst() []byte {
return l.b[l.n:]
}
// Chain returns a Transformer that applies t in sequence.
func Chain(t ...Transformer) Transformer {
if len(t) == 0 {
return nop{}
}
c := &chain{link: make([]link, len(t)+1)}
for i, tt := range t {
c.link[i].t = tt
}
// Allocate intermediate buffers.
b := make([][defaultBufSize]byte, len(t)-1)
for i := range b {
c.link[i+1].b = b[i][:]
}
return c
}
// Reset resets the state of Chain. It calls Reset on all the Transformers.
func (c *chain) Reset() {
for i, l := range c.link {
if l.t != nil {
l.t.Reset()
}
c.link[i].p, c.link[i].n = 0, 0
}
}
// TODO: make chain use Span (is going to be fun to implement!)
// Transform applies the transformers of c in sequence.
func (c *chain) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
// Set up src and dst in the chain.
srcL := &c.link[0]
dstL := &c.link[len(c.link)-1]
srcL.b, srcL.p, srcL.n = src, 0, len(src)
dstL.b, dstL.n = dst, 0
var lastFull, needProgress bool // for detecting progress
// i is the index of the next Transformer to apply, for i in [low, high].
// low is the lowest index for which c.link[low] may still produce bytes.
// high is the highest index for which c.link[high] has a Transformer.
// The error returned by Transform determines whether to increase or
// decrease i. We try to completely fill a buffer before converting it.
for low, i, high := c.errStart, c.errStart, len(c.link)-2; low <= i && i <= high; {
in, out := &c.link[i], &c.link[i+1]
nDst, nSrc, err0 := in.t.Transform(out.dst(), in.src(), atEOF && low == i)
out.n += nDst
in.p += nSrc
if i > 0 && in.p == in.n {
in.p, in.n = 0, 0
}
needProgress, lastFull = lastFull, false
switch err0 {
case ErrShortDst:
// Process the destination buffer next. Return if we are already
// at the high index.
if i == high {
return dstL.n, srcL.p, ErrShortDst
}
if out.n != 0 {
i++
// If the Transformer at the next index is not able to process any
// source bytes there is nothing that can be done to make progress
// and the bytes will remain unprocessed. lastFull is used to
// detect this and break out of the loop with a fatal error.
lastFull = true
continue
}
// The destination buffer was too small, but is completely empty.
// Return a fatal error as this transformation can never complete.
c.fatalError(i, errShortInternal)
case ErrShortSrc:
if i == 0 {
// Save ErrShortSrc in err. All other errors take precedence.
err = ErrShortSrc
break
}
// Source bytes were depleted before filling up the destination buffer.
// Verify we made some progress, move the remaining bytes to the errStart
// and try to get more source bytes.
if needProgress && nSrc == 0 || in.n-in.p == len(in.b) {
// There were not enough source bytes to proceed while the source
// buffer cannot hold any more bytes. Return a fatal error as this
// transformation can never complete.
c.fatalError(i, errShortInternal)
break
}
// in.b is an internal buffer and we can make progress.
in.p, in.n = 0, copy(in.b, in.src())
fallthrough
case nil:
// if i == low, we have depleted the bytes at index i or any lower levels.
// In that case we increase low and i. In all other cases we decrease i to
// fetch more bytes before proceeding to the next index.
if i > low {
i--
continue
}
default:
c.fatalError(i, err0)
}
// Exhausted level low or fatal error: increase low and continue
// to process the bytes accepted so far.
i++
low = i
}
// If c.errStart > 0, this means we found a fatal error. We will clear
// all upstream buffers. At this point, no more progress can be made
// downstream, as Transform would have bailed while handling ErrShortDst.
if c.errStart > 0 {
for i := 1; i < c.errStart; i++ {
c.link[i].p, c.link[i].n = 0, 0
}
err, c.errStart, c.err = c.err, 0, nil
}
return dstL.n, srcL.p, err
}
// Deprecated: Use runes.Remove instead.
func RemoveFunc(f func(r rune) bool) Transformer {
return removeF(f)
}
type removeF func(r rune) bool
func (removeF) Reset() {}
// Transform implements the Transformer interface.
func (t removeF) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
for r, sz := rune(0), 0; len(src) > 0; src = src[sz:] {
if r = rune(src[0]); r < utf8.RuneSelf {
sz = 1
} else {
r, sz = utf8.DecodeRune(src)
if sz == 1 {
// Invalid rune.
if !atEOF && !utf8.FullRune(src) {
err = ErrShortSrc
break
}
// We replace illegal bytes with RuneError. Not doing so might
// otherwise turn a sequence of invalid UTF-8 into valid UTF-8.
// The resulting byte sequence may subsequently contain runes
// for which t(r) is true that were passed unnoticed.
if !t(r) {
if nDst+3 > len(dst) {
err = ErrShortDst
break
}
nDst += copy(dst[nDst:], "\uFFFD")
}
nSrc++
continue
}
}
if !t(r) {
if nDst+sz > len(dst) {
err = ErrShortDst
break
}
nDst += copy(dst[nDst:], src[:sz])
}
nSrc += sz
}
return
}
// grow returns a new []byte that is longer than b, and copies the first n bytes
// of b to the start of the new slice.
func grow(b []byte, n int) []byte {
m := len(b)
if m <= 32 {
m = 64
} else if m <= 256 {
m *= 2
} else {
m += m >> 1
}
buf := make([]byte, m)
copy(buf, b[:n])
return buf
}
const initialBufSize = 128
// String returns a string with the result of converting s[:n] using t, where
// n <= len(s). If err == nil, n will be len(s). It calls Reset on t.
func String(t Transformer, s string) (result string, n int, err error) {
t.Reset()
if s == "" {
// Fast path for the common case for empty input. Results in about a
// 86% reduction of running time for BenchmarkStringLowerEmpty.
if _, _, err := t.Transform(nil, nil, true); err == nil {
return "", 0, nil
}
}
// Allocate only once. Note that both dst and src escape when passed to
// Transform.
buf := [2 * initialBufSize]byte{}
dst := buf[:initialBufSize:initialBufSize]
src := buf[initialBufSize : 2*initialBufSize]
// The input string s is transformed in multiple chunks (starting with a
// chunk size of initialBufSize). nDst and nSrc are per-chunk (or
// per-Transform-call) indexes, pDst and pSrc are overall indexes.
nDst, nSrc := 0, 0
pDst, pSrc := 0, 0
// pPrefix is the length of a common prefix: the first pPrefix bytes of the
// result will equal the first pPrefix bytes of s. It is not guaranteed to
// be the largest such value, but if pPrefix, len(result) and len(s) are
// all equal after the final transform (i.e. calling Transform with atEOF
// being true returned nil error) then we don't need to allocate a new
// result string.
pPrefix := 0
for {
// Invariant: pDst == pPrefix && pSrc == pPrefix.
n := copy(src, s[pSrc:])
nDst, nSrc, err = t.Transform(dst, src[:n], pSrc+n == len(s))
pDst += nDst
pSrc += nSrc
// TODO: let transformers implement an optional Spanner interface, akin
// to norm's QuickSpan. This would even allow us to avoid any allocation.
if !bytes.Equal(dst[:nDst], src[:nSrc]) {
break
}
pPrefix = pSrc
if err == ErrShortDst {
// A buffer can only be short if a transformer modifies its input.
break
} else if err == ErrShortSrc {
if nSrc == 0 {
// No progress was made.
break
}
// Equal so far and !atEOF, so continue checking.
} else if err != nil || pPrefix == len(s) {
return string(s[:pPrefix]), pPrefix, err
}
}
// Post-condition: pDst == pPrefix + nDst && pSrc == pPrefix + nSrc.
// We have transformed the first pSrc bytes of the input s to become pDst
// transformed bytes. Those transformed bytes are discontiguous: the first
// pPrefix of them equal s[:pPrefix] and the last nDst of them equal
// dst[:nDst]. We copy them around, into a new dst buffer if necessary, so
// that they become one contiguous slice: dst[:pDst].
if pPrefix != 0 {
newDst := dst
if pDst > len(newDst) {
newDst = make([]byte, len(s)+nDst-nSrc)
}
copy(newDst[pPrefix:pDst], dst[:nDst])
copy(newDst[:pPrefix], s[:pPrefix])
dst = newDst
}
// Prevent duplicate Transform calls with atEOF being true at the end of
// the input. Also return if we have an unrecoverable error.
if (err == nil && pSrc == len(s)) ||
(err != nil && err != ErrShortDst && err != ErrShortSrc) {
return string(dst[:pDst]), pSrc, err
}
// Transform the remaining input, growing dst and src buffers as necessary.
for {
n := copy(src, s[pSrc:])
atEOF := pSrc+n == len(s)
nDst, nSrc, err := t.Transform(dst[pDst:], src[:n], atEOF)
pDst += nDst
pSrc += nSrc
// If we got ErrShortDst or ErrShortSrc, do not grow as long as we can
// make progress. This may avoid excessive allocations.
if err == ErrShortDst {
if nDst == 0 {
dst = grow(dst, pDst)
}
} else if err == ErrShortSrc {
if atEOF {
return string(dst[:pDst]), pSrc, err
}
if nSrc == 0 {
src = grow(src, 0)
}
} else if err != nil || pSrc == len(s) {
return string(dst[:pDst]), pSrc, err
}
}
}
// Bytes returns a new byte slice with the result of converting b[:n] using t,
// where n <= len(b). If err == nil, n will be len(b). It calls Reset on t.
func Bytes(t Transformer, b []byte) (result []byte, n int, err error) {
return doAppend(t, 0, make([]byte, len(b)), b)
}
// Append appends the result of converting src[:n] using t to dst, where
// n <= len(src), If err == nil, n will be len(src). It calls Reset on t.
func Append(t Transformer, dst, src []byte) (result []byte, n int, err error) {
if len(dst) == cap(dst) {
n := len(src) + len(dst) // It is okay for this to be 0.
b := make([]byte, n)
dst = b[:copy(b, dst)]
}
return doAppend(t, len(dst), dst[:cap(dst)], src)
}
func doAppend(t Transformer, pDst int, dst, src []byte) (result []byte, n int, err error) {
t.Reset()
pSrc := 0
for {
nDst, nSrc, err := t.Transform(dst[pDst:], src[pSrc:], true)
pDst += nDst
pSrc += nSrc
if err != ErrShortDst {
return dst[:pDst], pSrc, err
}
// Grow the destination buffer, but do not grow as long as we can make
// progress. This may avoid excessive allocations.
if nDst == 0 {
dst = grow(dst, pDst)
}
}
}
+512
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
import "unicode/utf8"
const (
maxNonStarters = 30
// The maximum number of characters needed for a buffer is
// maxNonStarters + 1 for the starter + 1 for the GCJ
maxBufferSize = maxNonStarters + 2
maxNFCExpansion = 3 // NFC(0x1D160)
maxNFKCExpansion = 18 // NFKC(0xFDFA)
maxByteBufferSize = utf8.UTFMax * maxBufferSize // 128
)
// ssState is used for reporting the segment state after inserting a rune.
// It is returned by streamSafe.next.
type ssState int
const (
// Indicates a rune was successfully added to the segment.
ssSuccess ssState = iota
// Indicates a rune starts a new segment and should not be added.
ssStarter
// Indicates a rune caused a segment overflow and a CGJ should be inserted.
ssOverflow
)
// streamSafe implements the policy of when a CGJ should be inserted.
type streamSafe uint8
// first inserts the first rune of a segment. It is a faster version of next if
// it is known p represents the first rune in a segment.
func (ss *streamSafe) first(p Properties) {
*ss = streamSafe(p.nTrailingNonStarters())
}
// insert returns a ssState value to indicate whether a rune represented by p
// can be inserted.
func (ss *streamSafe) next(p Properties) ssState {
if *ss > maxNonStarters {
panic("streamSafe was not reset")
}
n := p.nLeadingNonStarters()
if *ss += streamSafe(n); *ss > maxNonStarters {
*ss = 0
return ssOverflow
}
// The Stream-Safe Text Processing prescribes that the counting can stop
// as soon as a starter is encountered. However, there are some starters,
// like Jamo V and T, that can combine with other runes, leaving their
// successive non-starters appended to the previous, possibly causing an
// overflow. We will therefore consider any rune with a non-zero nLead to
// be a non-starter. Note that it always hold that if nLead > 0 then
// nLead == nTrail.
if n == 0 {
*ss = streamSafe(p.nTrailingNonStarters())
return ssStarter
}
return ssSuccess
}
// backwards is used for checking for overflow and segment starts
// when traversing a string backwards. Users do not need to call first
// for the first rune. The state of the streamSafe retains the count of
// the non-starters loaded.
func (ss *streamSafe) backwards(p Properties) ssState {
if *ss > maxNonStarters {
panic("streamSafe was not reset")
}
c := *ss + streamSafe(p.nTrailingNonStarters())
if c > maxNonStarters {
return ssOverflow
}
*ss = c
if p.nLeadingNonStarters() == 0 {
return ssStarter
}
return ssSuccess
}
func (ss streamSafe) isMax() bool {
return ss == maxNonStarters
}
// GraphemeJoiner is inserted after maxNonStarters non-starter runes.
const GraphemeJoiner = "\u034F"
// reorderBuffer is used to normalize a single segment. Characters inserted with
// insert are decomposed and reordered based on CCC. The compose method can
// be used to recombine characters. Note that the byte buffer does not hold
// the UTF-8 characters in order. Only the rune array is maintained in sorted
// order. flush writes the resulting segment to a byte array.
type reorderBuffer struct {
rune [maxBufferSize]Properties // Per character info.
byte [maxByteBufferSize]byte // UTF-8 buffer. Referenced by runeInfo.pos.
nbyte uint8 // Number or bytes.
ss streamSafe // For limiting length of non-starter sequence.
nrune int // Number of runeInfos.
f formInfo
src input
nsrc int
tmpBytes input
out []byte
flushF func(*reorderBuffer) bool
}
func (rb *reorderBuffer) init(f Form, src []byte) {
rb.f = *formTable[f]
rb.src.setBytes(src)
rb.nsrc = len(src)
rb.ss = 0
}
func (rb *reorderBuffer) initString(f Form, src string) {
rb.f = *formTable[f]
rb.src.setString(src)
rb.nsrc = len(src)
rb.ss = 0
}
func (rb *reorderBuffer) setFlusher(out []byte, f func(*reorderBuffer) bool) {
rb.out = out
rb.flushF = f
}
// reset discards all characters from the buffer.
func (rb *reorderBuffer) reset() {
rb.nrune = 0
rb.nbyte = 0
}
func (rb *reorderBuffer) doFlush() bool {
if rb.f.composing {
rb.compose()
}
res := rb.flushF(rb)
rb.reset()
return res
}
// appendFlush appends the normalized segment to rb.out.
func appendFlush(rb *reorderBuffer) bool {
for i := 0; i < rb.nrune; i++ {
start := rb.rune[i].pos
end := start + rb.rune[i].size
rb.out = append(rb.out, rb.byte[start:end]...)
}
return true
}
// flush appends the normalized segment to out and resets rb.
func (rb *reorderBuffer) flush(out []byte) []byte {
for i := 0; i < rb.nrune; i++ {
start := rb.rune[i].pos
end := start + rb.rune[i].size
out = append(out, rb.byte[start:end]...)
}
rb.reset()
return out
}
// flushCopy copies the normalized segment to buf and resets rb.
// It returns the number of bytes written to buf.
func (rb *reorderBuffer) flushCopy(buf []byte) int {
p := 0
for i := 0; i < rb.nrune; i++ {
runep := rb.rune[i]
p += copy(buf[p:], rb.byte[runep.pos:runep.pos+runep.size])
}
rb.reset()
return p
}
// insertOrdered inserts a rune in the buffer, ordered by Canonical Combining Class.
// It returns false if the buffer is not large enough to hold the rune.
// It is used internally by insert and insertString only.
func (rb *reorderBuffer) insertOrdered(info Properties) {
n := rb.nrune
b := rb.rune[:]
cc := info.ccc
if cc > 0 {
// Find insertion position + move elements to make room.
for ; n > 0; n-- {
if b[n-1].ccc <= cc {
break
}
b[n] = b[n-1]
}
}
rb.nrune += 1
pos := uint8(rb.nbyte)
rb.nbyte += utf8.UTFMax
info.pos = pos
b[n] = info
}
// insertErr is an error code returned by insert. Using this type instead
// of error improves performance up to 20% for many of the benchmarks.
type insertErr int
const (
iSuccess insertErr = -iota
iShortDst
iShortSrc
)
// insertFlush inserts the given rune in the buffer ordered by CCC.
// If a decomposition with multiple segments are encountered, they leading
// ones are flushed.
// It returns a non-zero error code if the rune was not inserted.
func (rb *reorderBuffer) insertFlush(src input, i int, info Properties) insertErr {
if rune := src.hangul(i); rune != 0 {
rb.decomposeHangul(rune)
return iSuccess
}
if info.hasDecomposition() {
return rb.insertDecomposed(info.Decomposition())
}
rb.insertSingle(src, i, info)
return iSuccess
}
// insertUnsafe inserts the given rune in the buffer ordered by CCC.
// It is assumed there is sufficient space to hold the runes. It is the
// responsibility of the caller to ensure this. This can be done by checking
// the state returned by the streamSafe type.
func (rb *reorderBuffer) insertUnsafe(src input, i int, info Properties) {
if rune := src.hangul(i); rune != 0 {
rb.decomposeHangul(rune)
}
if info.hasDecomposition() {
// TODO: inline.
rb.insertDecomposed(info.Decomposition())
} else {
rb.insertSingle(src, i, info)
}
}
// insertDecomposed inserts an entry in to the reorderBuffer for each rune
// in dcomp. dcomp must be a sequence of decomposed UTF-8-encoded runes.
// It flushes the buffer on each new segment start.
func (rb *reorderBuffer) insertDecomposed(dcomp []byte) insertErr {
rb.tmpBytes.setBytes(dcomp)
// As the streamSafe accounting already handles the counting for modifiers,
// we don't have to call next. However, we do need to keep the accounting
// intact when flushing the buffer.
for i := 0; i < len(dcomp); {
info := rb.f.info(rb.tmpBytes, i)
if info.BoundaryBefore() && rb.nrune > 0 && !rb.doFlush() {
return iShortDst
}
i += copy(rb.byte[rb.nbyte:], dcomp[i:i+int(info.size)])
rb.insertOrdered(info)
}
return iSuccess
}
// insertSingle inserts an entry in the reorderBuffer for the rune at
// position i. info is the runeInfo for the rune at position i.
func (rb *reorderBuffer) insertSingle(src input, i int, info Properties) {
src.copySlice(rb.byte[rb.nbyte:], i, i+int(info.size))
rb.insertOrdered(info)
}
// insertCGJ inserts a Combining Grapheme Joiner (0x034f) into rb.
func (rb *reorderBuffer) insertCGJ() {
rb.insertSingle(input{str: GraphemeJoiner}, 0, Properties{size: uint8(len(GraphemeJoiner))})
}
// appendRune inserts a rune at the end of the buffer. It is used for Hangul.
func (rb *reorderBuffer) appendRune(r rune) {
bn := rb.nbyte
sz := utf8.EncodeRune(rb.byte[bn:], rune(r))
rb.nbyte += utf8.UTFMax
rb.rune[rb.nrune] = Properties{pos: bn, size: uint8(sz)}
rb.nrune++
}
// assignRune sets a rune at position pos. It is used for Hangul and recomposition.
func (rb *reorderBuffer) assignRune(pos int, r rune) {
bn := rb.rune[pos].pos
sz := utf8.EncodeRune(rb.byte[bn:], rune(r))
rb.rune[pos] = Properties{pos: bn, size: uint8(sz)}
}
// runeAt returns the rune at position n. It is used for Hangul and recomposition.
func (rb *reorderBuffer) runeAt(n int) rune {
inf := rb.rune[n]
r, _ := utf8.DecodeRune(rb.byte[inf.pos : inf.pos+inf.size])
return r
}
// bytesAt returns the UTF-8 encoding of the rune at position n.
// It is used for Hangul and recomposition.
func (rb *reorderBuffer) bytesAt(n int) []byte {
inf := rb.rune[n]
return rb.byte[inf.pos : int(inf.pos)+int(inf.size)]
}
// For Hangul we combine algorithmically, instead of using tables.
const (
hangulBase = 0xAC00 // UTF-8(hangulBase) -> EA B0 80
hangulBase0 = 0xEA
hangulBase1 = 0xB0
hangulBase2 = 0x80
hangulEnd = hangulBase + jamoLVTCount // UTF-8(0xD7A4) -> ED 9E A4
hangulEnd0 = 0xED
hangulEnd1 = 0x9E
hangulEnd2 = 0xA4
jamoLBase = 0x1100 // UTF-8(jamoLBase) -> E1 84 00
jamoLBase0 = 0xE1
jamoLBase1 = 0x84
jamoLEnd = 0x1113
jamoVBase = 0x1161
jamoVEnd = 0x1176
jamoTBase = 0x11A7
jamoTEnd = 0x11C3
jamoTCount = 28
jamoVCount = 21
jamoVTCount = 21 * 28
jamoLVTCount = 19 * 21 * 28
)
const hangulUTF8Size = 3
func isHangul(b []byte) bool {
if len(b) < hangulUTF8Size {
return false
}
b0 := b[0]
if b0 < hangulBase0 {
return false
}
b1 := b[1]
switch {
case b0 == hangulBase0:
return b1 >= hangulBase1
case b0 < hangulEnd0:
return true
case b0 > hangulEnd0:
return false
case b1 < hangulEnd1:
return true
}
return b1 == hangulEnd1 && b[2] < hangulEnd2
}
func isHangulString(b string) bool {
if len(b) < hangulUTF8Size {
return false
}
b0 := b[0]
if b0 < hangulBase0 {
return false
}
b1 := b[1]
switch {
case b0 == hangulBase0:
return b1 >= hangulBase1
case b0 < hangulEnd0:
return true
case b0 > hangulEnd0:
return false
case b1 < hangulEnd1:
return true
}
return b1 == hangulEnd1 && b[2] < hangulEnd2
}
// Caller must ensure len(b) >= 2.
func isJamoVT(b []byte) bool {
// True if (rune & 0xff00) == jamoLBase
return b[0] == jamoLBase0 && (b[1]&0xFC) == jamoLBase1
}
func isHangulWithoutJamoT(b []byte) bool {
c, _ := utf8.DecodeRune(b)
c -= hangulBase
return c < jamoLVTCount && c%jamoTCount == 0
}
// decomposeHangul writes the decomposed Hangul to buf and returns the number
// of bytes written. len(buf) should be at least 9.
func decomposeHangul(buf []byte, r rune) int {
const JamoUTF8Len = 3
r -= hangulBase
x := r % jamoTCount
r /= jamoTCount
utf8.EncodeRune(buf, jamoLBase+r/jamoVCount)
utf8.EncodeRune(buf[JamoUTF8Len:], jamoVBase+r%jamoVCount)
if x != 0 {
utf8.EncodeRune(buf[2*JamoUTF8Len:], jamoTBase+x)
return 3 * JamoUTF8Len
}
return 2 * JamoUTF8Len
}
// decomposeHangul algorithmically decomposes a Hangul rune into
// its Jamo components.
// See https://unicode.org/reports/tr15/#Hangul for details on decomposing Hangul.
func (rb *reorderBuffer) decomposeHangul(r rune) {
r -= hangulBase
x := r % jamoTCount
r /= jamoTCount
rb.appendRune(jamoLBase + r/jamoVCount)
rb.appendRune(jamoVBase + r%jamoVCount)
if x != 0 {
rb.appendRune(jamoTBase + x)
}
}
// combineHangul algorithmically combines Jamo character components into Hangul.
// See https://unicode.org/reports/tr15/#Hangul for details on combining Hangul.
func (rb *reorderBuffer) combineHangul(s, i, k int) {
b := rb.rune[:]
bn := rb.nrune
for ; i < bn; i++ {
cccB := b[k-1].ccc
cccC := b[i].ccc
if cccB == 0 {
s = k - 1
}
if s != k-1 && cccB >= cccC {
// b[i] is blocked by greater-equal cccX below it
b[k] = b[i]
k++
} else {
l := rb.runeAt(s) // also used to compare to hangulBase
v := rb.runeAt(i) // also used to compare to jamoT
switch {
case jamoLBase <= l && l < jamoLEnd &&
jamoVBase <= v && v < jamoVEnd:
// 11xx plus 116x to LV
rb.assignRune(s, hangulBase+
(l-jamoLBase)*jamoVTCount+(v-jamoVBase)*jamoTCount)
case hangulBase <= l && l < hangulEnd &&
jamoTBase < v && v < jamoTEnd &&
((l-hangulBase)%jamoTCount) == 0:
// ACxx plus 11Ax to LVT
rb.assignRune(s, l+v-jamoTBase)
default:
b[k] = b[i]
k++
}
}
}
rb.nrune = k
}
// compose recombines the runes in the buffer.
// It should only be used to recompose a single segment, as it will not
// handle alternations between Hangul and non-Hangul characters correctly.
func (rb *reorderBuffer) compose() {
// Lazily load the map used by the combine func below, but do
// it outside of the loop.
recompMapOnce.Do(buildRecompMap)
// UAX #15, section X5 , including Corrigendum #5
// "In any character sequence beginning with starter S, a character C is
// blocked from S if and only if there is some character B between S
// and C, and either B is a starter or it has the same or higher
// combining class as C."
bn := rb.nrune
if bn == 0 {
return
}
k := 1
b := rb.rune[:]
for s, i := 0, 1; i < bn; i++ {
if isJamoVT(rb.bytesAt(i)) {
// Redo from start in Hangul mode. Necessary to support
// U+320E..U+321E in NFKC mode.
rb.combineHangul(s, i, k)
return
}
ii := b[i]
// We can only use combineForward as a filter if we later
// get the info for the combined character. This is more
// expensive than using the filter. Using combinesBackward()
// is safe.
if ii.combinesBackward() {
cccB := b[k-1].ccc
cccC := ii.ccc
blocked := false // b[i] blocked by starter or greater or equal CCC?
if cccB == 0 {
s = k - 1
} else {
blocked = s != k-1 && cccB >= cccC
}
if !blocked {
combined := combine(rb.runeAt(s), rb.runeAt(i))
if combined != 0 {
rb.assignRune(s, combined)
continue
}
}
}
b[k] = b[i]
k++
}
rb.nrune = k
}
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
import "encoding/binary"
// This file contains Form-specific logic and wrappers for data in tables.go.
// Rune info is stored in a separate trie per composing form. A composing form
// and its corresponding decomposing form share the same trie. Each trie maps
// a rune to a uint16. The values take two forms. For v >= 0x8000:
// bits
// 15: 1 (inverse of NFD_QC bit of qcInfo)
// 13..7: qcInfo (see below). isYesD is always true (no decompostion).
// 6..0: ccc (compressed CCC value).
// For v < 0x8000, the respective rune has a decomposition and v is an index
// into a byte array of UTF-8 decomposition sequences and additional info and
// has the form:
// <header> <decomp_byte>* [<tccc> [<lccc>]]
// The header contains the number of bytes in the decomposition (excluding this
// length byte). The two most significant bits of this length byte correspond
// to bit 5 and 4 of qcInfo (see below). The byte sequence itself starts at v+1.
// The byte sequence is followed by a trailing and leading CCC if the values
// for these are not zero. The value of v determines which ccc are appended
// to the sequences. For v < firstCCC, there are none, for v >= firstCCC,
// the sequence is followed by a trailing ccc, and for v >= firstLeadingCC
// there is an additional leading ccc. The value of tccc itself is the
// trailing CCC shifted left 2 bits. The two least-significant bits of tccc
// are the number of trailing non-starters.
const (
qcInfoMask = 0x3F // to clear all but the relevant bits in a qcInfo
headerLenMask = 0x3F // extract the length value from the header byte
headerFlagsMask = 0xC0 // extract the qcInfo bits from the header byte
)
// Properties provides access to normalization properties of a rune.
type Properties struct {
pos uint8 // start position in reorderBuffer; used in composition.go
size uint8 // length of UTF-8 encoding of this rune
ccc uint8 // leading canonical combining class (ccc if not decomposition)
tccc uint8 // trailing canonical combining class (ccc if not decomposition)
nLead uint8 // number of leading non-starters.
flags qcInfo // quick check flags
index uint16
}
// functions dispatchable per form
type lookupFunc func(b input, i int) Properties
// formInfo holds Form-specific functions and tables.
type formInfo struct {
form Form
composing, compatibility bool // form type
info lookupFunc
nextMain iterFunc
}
var formTable = []*formInfo{{
form: NFC,
composing: true,
compatibility: false,
info: lookupInfoNFC,
nextMain: nextComposed,
}, {
form: NFD,
composing: false,
compatibility: false,
info: lookupInfoNFC,
nextMain: nextDecomposed,
}, {
form: NFKC,
composing: true,
compatibility: true,
info: lookupInfoNFKC,
nextMain: nextComposed,
}, {
form: NFKD,
composing: false,
compatibility: true,
info: lookupInfoNFKC,
nextMain: nextDecomposed,
}}
// We do not distinguish between boundaries for NFC, NFD, etc. to avoid
// unexpected behavior for the user. For example, in NFD, there is a boundary
// after 'a'. However, 'a' might combine with modifiers, so from the application's
// perspective it is not a good boundary. We will therefore always use the
// boundaries for the combining variants.
// BoundaryBefore returns true if this rune starts a new segment and
// cannot combine with any rune on the left.
func (p Properties) BoundaryBefore() bool {
if p.ccc == 0 && !p.combinesBackward() {
return true
}
// We assume that the CCC of the first character in a decomposition
// is always non-zero if different from info.ccc and that we can return
// false at this point. This is verified by maketables.
return false
}
// BoundaryAfter returns true if runes cannot combine with or otherwise
// interact with this or previous runes.
func (p Properties) BoundaryAfter() bool {
// TODO: loosen these conditions.
return p.isInert()
}
// We pack quick check data in 4 bits:
// 5: Combines forward (0 == false, 1 == true)
// 4..3: NFC_QC Yes(00), No (10), or Maybe (11)
// 2: NFD_QC Yes (0) or No (1). No also means there is a decomposition.
// 1..0: Number of trailing non-starters.
//
// When all 4 bits are zero, the character is inert, meaning it is never
// influenced by normalization.
type qcInfo uint8
func (p Properties) isYesC() bool { return p.flags&0x10 == 0 }
func (p Properties) isYesD() bool { return p.flags&0x4 == 0 }
func (p Properties) combinesForward() bool { return p.flags&0x20 != 0 }
func (p Properties) combinesBackward() bool { return p.flags&0x8 != 0 } // == isMaybe
func (p Properties) hasDecomposition() bool { return p.flags&0x4 != 0 } // == isNoD
func (p Properties) isInert() bool {
return p.flags&qcInfoMask == 0 && p.ccc == 0
}
func (p Properties) multiSegment() bool {
return p.index >= firstMulti && p.index < endMulti
}
func (p Properties) nLeadingNonStarters() uint8 {
return p.nLead
}
func (p Properties) nTrailingNonStarters() uint8 {
return uint8(p.flags & 0x03)
}
// Decomposition returns the decomposition for the underlying rune
// or nil if there is none.
func (p Properties) Decomposition() []byte {
// TODO: create the decomposition for Hangul?
if p.index == 0 {
return nil
}
i := p.index
n := decomps[i] & headerLenMask
i++
return decomps[i : i+uint16(n)]
}
// Size returns the length of UTF-8 encoding of the rune.
func (p Properties) Size() int {
return int(p.size)
}
// CCC returns the canonical combining class of the underlying rune.
func (p Properties) CCC() uint8 {
if p.index >= firstCCCZeroExcept {
return 0
}
return ccc[p.ccc]
}
// LeadCCC returns the CCC of the first rune in the decomposition.
// If there is no decomposition, LeadCCC equals CCC.
func (p Properties) LeadCCC() uint8 {
return ccc[p.ccc]
}
// TrailCCC returns the CCC of the last rune in the decomposition.
// If there is no decomposition, TrailCCC equals CCC.
func (p Properties) TrailCCC() uint8 {
return ccc[p.tccc]
}
func buildRecompMap() {
recompMap = make(map[uint32]rune, len(recompMapPacked)/8)
var buf [8]byte
for i := 0; i < len(recompMapPacked); i += 8 {
copy(buf[:], recompMapPacked[i:i+8])
key := binary.BigEndian.Uint32(buf[:4])
val := binary.BigEndian.Uint32(buf[4:])
recompMap[key] = rune(val)
}
}
// Recomposition
// We use 32-bit keys instead of 64-bit for the two codepoint keys.
// This clips off the bits of three entries, but we know this will not
// result in a collision. In the unlikely event that changes to
// UnicodeData.txt introduce collisions, the compiler will catch it.
// Note that the recomposition map for NFC and NFKC are identical.
// combine returns the combined rune or 0 if it doesn't exist.
//
// The caller is responsible for calling
// recompMapOnce.Do(buildRecompMap) sometime before this is called.
func combine(a, b rune) rune {
key := uint32(uint16(a))<<16 + uint32(uint16(b))
if recompMap == nil {
panic("caller error") // see func comment
}
return recompMap[key]
}
func lookupInfoNFC(b input, i int) Properties {
v, sz := b.charinfoNFC(i)
return compInfo(v, sz)
}
func lookupInfoNFKC(b input, i int) Properties {
v, sz := b.charinfoNFKC(i)
return compInfo(v, sz)
}
// Properties returns properties for the first rune in s.
func (f Form) Properties(s []byte) Properties {
if f == NFC || f == NFD {
return compInfo(nfcData.lookup(s))
}
return compInfo(nfkcData.lookup(s))
}
// PropertiesString returns properties for the first rune in s.
func (f Form) PropertiesString(s string) Properties {
if f == NFC || f == NFD {
return compInfo(nfcData.lookupString(s))
}
return compInfo(nfkcData.lookupString(s))
}
// compInfo converts the information contained in v and sz
// to a Properties. See the comment at the top of the file
// for more information on the format.
func compInfo(v uint16, sz int) Properties {
if v == 0 {
return Properties{size: uint8(sz)}
} else if v >= 0x8000 {
p := Properties{
size: uint8(sz),
ccc: uint8(v),
tccc: uint8(v),
flags: qcInfo(v >> 8),
}
if p.ccc > 0 || p.combinesBackward() {
p.nLead = uint8(p.flags & 0x3)
}
return p
}
// has decomposition
h := decomps[v]
f := (qcInfo(h&headerFlagsMask) >> 2) | 0x4
p := Properties{size: uint8(sz), flags: f, index: v}
if v >= firstCCC {
v += uint16(h&headerLenMask) + 1
c := decomps[v]
p.tccc = c >> 2
p.flags |= qcInfo(c & 0x3)
if v >= firstLeadingCCC {
p.nLead = c & 0x3
if v >= firstStarterWithNLead {
// We were tricked. Remove the decomposition.
p.flags &= 0x03
p.index = 0
return p
}
p.ccc = decomps[v+1]
}
}
return p
}
+109
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
import "unicode/utf8"
type input struct {
str string
bytes []byte
}
func inputBytes(str []byte) input {
return input{bytes: str}
}
func inputString(str string) input {
return input{str: str}
}
func (in *input) setBytes(str []byte) {
in.str = ""
in.bytes = str
}
func (in *input) setString(str string) {
in.str = str
in.bytes = nil
}
func (in *input) _byte(p int) byte {
if in.bytes == nil {
return in.str[p]
}
return in.bytes[p]
}
func (in *input) skipASCII(p, max int) int {
if in.bytes == nil {
for ; p < max && in.str[p] < utf8.RuneSelf; p++ {
}
} else {
for ; p < max && in.bytes[p] < utf8.RuneSelf; p++ {
}
}
return p
}
func (in *input) skipContinuationBytes(p int) int {
if in.bytes == nil {
for ; p < len(in.str) && !utf8.RuneStart(in.str[p]); p++ {
}
} else {
for ; p < len(in.bytes) && !utf8.RuneStart(in.bytes[p]); p++ {
}
}
return p
}
func (in *input) appendSlice(buf []byte, b, e int) []byte {
if in.bytes != nil {
return append(buf, in.bytes[b:e]...)
}
for i := b; i < e; i++ {
buf = append(buf, in.str[i])
}
return buf
}
func (in *input) copySlice(buf []byte, b, e int) int {
if in.bytes == nil {
return copy(buf, in.str[b:e])
}
return copy(buf, in.bytes[b:e])
}
func (in *input) charinfoNFC(p int) (uint16, int) {
if in.bytes == nil {
return nfcData.lookupString(in.str[p:])
}
return nfcData.lookup(in.bytes[p:])
}
func (in *input) charinfoNFKC(p int) (uint16, int) {
if in.bytes == nil {
return nfkcData.lookupString(in.str[p:])
}
return nfkcData.lookup(in.bytes[p:])
}
func (in *input) hangul(p int) (r rune) {
var size int
if in.bytes == nil {
if !isHangulString(in.str[p:]) {
return 0
}
r, size = utf8.DecodeRuneInString(in.str[p:])
} else {
if !isHangul(in.bytes[p:]) {
return 0
}
r, size = utf8.DecodeRune(in.bytes[p:])
}
if size != hangulUTF8Size {
return 0
}
return r
}
+458
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
import (
"fmt"
"unicode/utf8"
)
// MaxSegmentSize is the maximum size of a byte buffer needed to consider any
// sequence of starter and non-starter runes for the purpose of normalization.
const MaxSegmentSize = maxByteBufferSize
// An Iter iterates over a string or byte slice, while normalizing it
// to a given Form.
type Iter struct {
rb reorderBuffer
buf [maxByteBufferSize]byte
info Properties // first character saved from previous iteration
next iterFunc // implementation of next depends on form
asciiF iterFunc
p int // current position in input source
multiSeg []byte // remainder of multi-segment decomposition
}
type iterFunc func(*Iter) []byte
// Init initializes i to iterate over src after normalizing it to Form f.
func (i *Iter) Init(f Form, src []byte) {
i.p = 0
if len(src) == 0 {
i.setDone()
i.rb.nsrc = 0
return
}
i.multiSeg = nil
i.rb.init(f, src)
i.next = i.rb.f.nextMain
i.asciiF = nextASCIIBytes
i.info = i.rb.f.info(i.rb.src, i.p)
i.rb.ss.first(i.info)
}
// InitString initializes i to iterate over src after normalizing it to Form f.
func (i *Iter) InitString(f Form, src string) {
i.p = 0
if len(src) == 0 {
i.setDone()
i.rb.nsrc = 0
return
}
i.multiSeg = nil
i.rb.initString(f, src)
i.next = i.rb.f.nextMain
i.asciiF = nextASCIIString
i.info = i.rb.f.info(i.rb.src, i.p)
i.rb.ss.first(i.info)
}
// Seek sets the segment to be returned by the next call to Next to start
// at position p. It is the responsibility of the caller to set p to the
// start of a segment.
func (i *Iter) Seek(offset int64, whence int) (int64, error) {
var abs int64
switch whence {
case 0:
abs = offset
case 1:
abs = int64(i.p) + offset
case 2:
abs = int64(i.rb.nsrc) + offset
default:
return 0, fmt.Errorf("norm: invalid whence")
}
if abs < 0 {
return 0, fmt.Errorf("norm: negative position")
}
if int(abs) >= i.rb.nsrc {
i.setDone()
return int64(i.p), nil
}
i.p = int(abs)
i.multiSeg = nil
i.next = i.rb.f.nextMain
i.info = i.rb.f.info(i.rb.src, i.p)
i.rb.ss.first(i.info)
return abs, nil
}
// returnSlice returns a slice of the underlying input type as a byte slice.
// If the underlying is of type []byte, it will simply return a slice.
// If the underlying is of type string, it will copy the slice to the buffer
// and return that.
func (i *Iter) returnSlice(a, b int) []byte {
if i.rb.src.bytes == nil {
return i.buf[:copy(i.buf[:], i.rb.src.str[a:b])]
}
return i.rb.src.bytes[a:b]
}
// Pos returns the byte position at which the next call to Next will commence processing.
func (i *Iter) Pos() int {
return i.p
}
func (i *Iter) setDone() {
i.next = nextDone
i.p = i.rb.nsrc
}
// Done returns true if there is no more input to process.
func (i *Iter) Done() bool {
return i.p >= i.rb.nsrc
}
// Next returns f(i.input[i.Pos():n]), where n is a boundary of i.input.
// For any input a and b for which f(a) == f(b), subsequent calls
// to Next will return the same segments.
// Modifying runes are grouped together with the preceding starter, if such a starter exists.
// Although not guaranteed, n will typically be the smallest possible n.
func (i *Iter) Next() []byte {
return i.next(i)
}
func nextASCIIBytes(i *Iter) []byte {
p := i.p + 1
if p >= i.rb.nsrc {
p0 := i.p
i.setDone()
return i.rb.src.bytes[p0:p]
}
if i.rb.src.bytes[p] < utf8.RuneSelf {
p0 := i.p
i.p = p
return i.rb.src.bytes[p0:p]
}
i.info = i.rb.f.info(i.rb.src, i.p)
i.next = i.rb.f.nextMain
return i.next(i)
}
func nextASCIIString(i *Iter) []byte {
p := i.p + 1
if p >= i.rb.nsrc {
i.buf[0] = i.rb.src.str[i.p]
i.setDone()
return i.buf[:1]
}
if i.rb.src.str[p] < utf8.RuneSelf {
i.buf[0] = i.rb.src.str[i.p]
i.p = p
return i.buf[:1]
}
i.info = i.rb.f.info(i.rb.src, i.p)
i.next = i.rb.f.nextMain
return i.next(i)
}
func nextHangul(i *Iter) []byte {
p := i.p
next := p + hangulUTF8Size
if next >= i.rb.nsrc {
i.setDone()
} else if i.rb.src.hangul(next) == 0 {
i.rb.ss.next(i.info)
i.info = i.rb.f.info(i.rb.src, i.p)
i.next = i.rb.f.nextMain
return i.next(i)
}
i.p = next
return i.buf[:decomposeHangul(i.buf[:], i.rb.src.hangul(p))]
}
func nextDone(i *Iter) []byte {
return nil
}
// nextMulti is used for iterating over multi-segment decompositions
// for decomposing normal forms.
func nextMulti(i *Iter) []byte {
j := 0
d := i.multiSeg
// skip first rune
for j = 1; j < len(d) && !utf8.RuneStart(d[j]); j++ {
}
for j < len(d) {
info := i.rb.f.info(input{bytes: d}, j)
if info.BoundaryBefore() {
i.multiSeg = d[j:]
return d[:j]
}
j += int(info.size)
}
// treat last segment as normal decomposition
i.next = i.rb.f.nextMain
return i.next(i)
}
// nextMultiNorm is used for iterating over multi-segment decompositions
// for composing normal forms.
func nextMultiNorm(i *Iter) []byte {
j := 0
d := i.multiSeg
for j < len(d) {
info := i.rb.f.info(input{bytes: d}, j)
if info.BoundaryBefore() {
i.rb.compose()
seg := i.buf[:i.rb.flushCopy(i.buf[:])]
i.rb.insertUnsafe(input{bytes: d}, j, info)
i.multiSeg = d[j+int(info.size):]
return seg
}
i.rb.insertUnsafe(input{bytes: d}, j, info)
j += int(info.size)
}
i.multiSeg = nil
i.next = nextComposed
return doNormComposed(i)
}
// nextDecomposed is the implementation of Next for forms NFD and NFKD.
func nextDecomposed(i *Iter) (next []byte) {
outp := 0
inCopyStart, outCopyStart := i.p, 0
for {
if sz := int(i.info.size); sz <= 1 {
i.rb.ss = 0
p := i.p
i.p++ // ASCII or illegal byte. Either way, advance by 1.
if i.p >= i.rb.nsrc {
i.setDone()
return i.returnSlice(p, i.p)
} else if i.rb.src._byte(i.p) < utf8.RuneSelf {
i.next = i.asciiF
return i.returnSlice(p, i.p)
}
outp++
} else if d := i.info.Decomposition(); d != nil {
// Note: If leading CCC != 0, then len(d) == 2 and last is also non-zero.
// Case 1: there is a leftover to copy. In this case the decomposition
// must begin with a modifier and should always be appended.
// Case 2: no leftover. Simply return d if followed by a ccc == 0 value.
p := outp + len(d)
if outp > 0 {
i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
// TODO: this condition should not be possible, but we leave it
// in for defensive purposes.
if p > len(i.buf) {
return i.buf[:outp]
}
} else if i.info.multiSegment() {
// outp must be 0 as multi-segment decompositions always
// start a new segment.
if i.multiSeg == nil {
i.multiSeg = d
i.next = nextMulti
return nextMulti(i)
}
// We are in the last segment. Treat as normal decomposition.
d = i.multiSeg
i.multiSeg = nil
p = len(d)
}
prevCC := i.info.tccc
if i.p += sz; i.p >= i.rb.nsrc {
i.setDone()
i.info = Properties{} // Force BoundaryBefore to succeed.
} else {
i.info = i.rb.f.info(i.rb.src, i.p)
}
switch i.rb.ss.next(i.info) {
case ssOverflow:
i.next = nextCGJDecompose
fallthrough
case ssStarter:
if outp > 0 {
copy(i.buf[outp:], d)
return i.buf[:p]
}
return d
}
copy(i.buf[outp:], d)
outp = p
inCopyStart, outCopyStart = i.p, outp
if i.info.ccc < prevCC {
goto doNorm
}
continue
} else if r := i.rb.src.hangul(i.p); r != 0 {
outp = decomposeHangul(i.buf[:], r)
i.p += hangulUTF8Size
inCopyStart, outCopyStart = i.p, outp
if i.p >= i.rb.nsrc {
i.setDone()
break
} else if i.rb.src.hangul(i.p) != 0 {
i.next = nextHangul
return i.buf[:outp]
}
} else {
p := outp + sz
if p > len(i.buf) {
break
}
outp = p
i.p += sz
}
if i.p >= i.rb.nsrc {
i.setDone()
break
}
prevCC := i.info.tccc
i.info = i.rb.f.info(i.rb.src, i.p)
if v := i.rb.ss.next(i.info); v == ssStarter {
break
} else if v == ssOverflow {
i.next = nextCGJDecompose
break
}
if i.info.ccc < prevCC {
goto doNorm
}
}
if outCopyStart == 0 {
return i.returnSlice(inCopyStart, i.p)
} else if inCopyStart < i.p {
i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
}
return i.buf[:outp]
doNorm:
// Insert what we have decomposed so far in the reorderBuffer.
// As we will only reorder, there will always be enough room.
i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
i.rb.insertDecomposed(i.buf[0:outp])
return doNormDecomposed(i)
}
func doNormDecomposed(i *Iter) []byte {
for {
i.rb.insertUnsafe(i.rb.src, i.p, i.info)
if i.p += int(i.info.size); i.p >= i.rb.nsrc {
i.setDone()
break
}
i.info = i.rb.f.info(i.rb.src, i.p)
if i.info.ccc == 0 {
break
}
if s := i.rb.ss.next(i.info); s == ssOverflow {
i.next = nextCGJDecompose
break
}
}
// new segment or too many combining characters: exit normalization
return i.buf[:i.rb.flushCopy(i.buf[:])]
}
func nextCGJDecompose(i *Iter) []byte {
i.rb.ss = 0
i.rb.insertCGJ()
i.next = nextDecomposed
i.rb.ss.first(i.info)
buf := doNormDecomposed(i)
return buf
}
// nextComposed is the implementation of Next for forms NFC and NFKC.
func nextComposed(i *Iter) []byte {
outp, startp := 0, i.p
var prevCC uint8
for {
if !i.info.isYesC() {
goto doNorm
}
prevCC = i.info.tccc
sz := int(i.info.size)
if sz == 0 {
sz = 1 // illegal rune: copy byte-by-byte
}
p := outp + sz
if p > len(i.buf) {
break
}
outp = p
i.p += sz
if i.p >= i.rb.nsrc {
i.setDone()
break
} else if i.rb.src._byte(i.p) < utf8.RuneSelf {
i.rb.ss = 0
i.next = i.asciiF
break
}
i.info = i.rb.f.info(i.rb.src, i.p)
if v := i.rb.ss.next(i.info); v == ssStarter {
break
} else if v == ssOverflow {
i.next = nextCGJCompose
break
}
if i.info.ccc < prevCC {
goto doNorm
}
}
return i.returnSlice(startp, i.p)
doNorm:
// reset to start position
i.p = startp
i.info = i.rb.f.info(i.rb.src, i.p)
i.rb.ss.first(i.info)
if i.info.multiSegment() {
d := i.info.Decomposition()
info := i.rb.f.info(input{bytes: d}, 0)
i.rb.insertUnsafe(input{bytes: d}, 0, info)
i.multiSeg = d[int(info.size):]
i.next = nextMultiNorm
return nextMultiNorm(i)
}
i.rb.ss.first(i.info)
i.rb.insertUnsafe(i.rb.src, i.p, i.info)
return doNormComposed(i)
}
func doNormComposed(i *Iter) []byte {
// First rune should already be inserted.
for {
if i.p += int(i.info.size); i.p >= i.rb.nsrc {
i.setDone()
break
}
i.info = i.rb.f.info(i.rb.src, i.p)
if s := i.rb.ss.next(i.info); s == ssStarter {
break
} else if s == ssOverflow {
i.next = nextCGJCompose
break
}
i.rb.insertUnsafe(i.rb.src, i.p, i.info)
}
i.rb.compose()
seg := i.buf[:i.rb.flushCopy(i.buf[:])]
return seg
}
func nextCGJCompose(i *Iter) []byte {
i.rb.ss = 0 // instead of first
i.rb.insertCGJ()
i.next = nextComposed
// Note that we treat any rune with nLeadingNonStarters > 0 as a non-starter,
// even if they are not. This is particularly dubious for U+FF9E and UFF9A.
// If we ever change that, insert a check here.
i.rb.ss.first(i.info)
i.rb.insertUnsafe(i.rb.src, i.p, i.info)
return doNormComposed(i)
}
+609
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@@ -0,0 +1,609 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Note: the file data_test.go that is generated should not be checked in.
//go:generate go run maketables.go triegen.go
//go:generate go test -tags test
// Package norm contains types and functions for normalizing Unicode strings.
package norm // import "golang.org/x/text/unicode/norm"
import (
"unicode/utf8"
"golang.org/x/text/transform"
)
// A Form denotes a canonical representation of Unicode code points.
// The Unicode-defined normalization and equivalence forms are:
//
// NFC Unicode Normalization Form C
// NFD Unicode Normalization Form D
// NFKC Unicode Normalization Form KC
// NFKD Unicode Normalization Form KD
//
// For a Form f, this documentation uses the notation f(x) to mean
// the bytes or string x converted to the given form.
// A position n in x is called a boundary if conversion to the form can
// proceed independently on both sides:
// f(x) == append(f(x[0:n]), f(x[n:])...)
//
// References: https://unicode.org/reports/tr15/ and
// https://unicode.org/notes/tn5/.
type Form int
const (
NFC Form = iota
NFD
NFKC
NFKD
)
// Bytes returns f(b). May return b if f(b) = b.
func (f Form) Bytes(b []byte) []byte {
src := inputBytes(b)
ft := formTable[f]
n, ok := ft.quickSpan(src, 0, len(b), true)
if ok {
return b
}
out := make([]byte, n, len(b))
copy(out, b[0:n])
rb := reorderBuffer{f: *ft, src: src, nsrc: len(b), out: out, flushF: appendFlush}
return doAppendInner(&rb, n)
}
// String returns f(s).
func (f Form) String(s string) string {
src := inputString(s)
ft := formTable[f]
n, ok := ft.quickSpan(src, 0, len(s), true)
if ok {
return s
}
out := make([]byte, n, len(s))
copy(out, s[0:n])
rb := reorderBuffer{f: *ft, src: src, nsrc: len(s), out: out, flushF: appendFlush}
return string(doAppendInner(&rb, n))
}
// IsNormal returns true if b == f(b).
func (f Form) IsNormal(b []byte) bool {
src := inputBytes(b)
ft := formTable[f]
bp, ok := ft.quickSpan(src, 0, len(b), true)
if ok {
return true
}
rb := reorderBuffer{f: *ft, src: src, nsrc: len(b)}
rb.setFlusher(nil, cmpNormalBytes)
for bp < len(b) {
rb.out = b[bp:]
if bp = decomposeSegment(&rb, bp, true); bp < 0 {
return false
}
bp, _ = rb.f.quickSpan(rb.src, bp, len(b), true)
}
return true
}
func cmpNormalBytes(rb *reorderBuffer) bool {
b := rb.out
for i := 0; i < rb.nrune; i++ {
info := rb.rune[i]
if int(info.size) > len(b) {
return false
}
p := info.pos
pe := p + info.size
for ; p < pe; p++ {
if b[0] != rb.byte[p] {
return false
}
b = b[1:]
}
}
return true
}
// IsNormalString returns true if s == f(s).
func (f Form) IsNormalString(s string) bool {
src := inputString(s)
ft := formTable[f]
bp, ok := ft.quickSpan(src, 0, len(s), true)
if ok {
return true
}
rb := reorderBuffer{f: *ft, src: src, nsrc: len(s)}
rb.setFlusher(nil, func(rb *reorderBuffer) bool {
for i := 0; i < rb.nrune; i++ {
info := rb.rune[i]
if bp+int(info.size) > len(s) {
return false
}
p := info.pos
pe := p + info.size
for ; p < pe; p++ {
if s[bp] != rb.byte[p] {
return false
}
bp++
}
}
return true
})
for bp < len(s) {
if bp = decomposeSegment(&rb, bp, true); bp < 0 {
return false
}
bp, _ = rb.f.quickSpan(rb.src, bp, len(s), true)
}
return true
}
// patchTail fixes a case where a rune may be incorrectly normalized
// if it is followed by illegal continuation bytes. It returns the
// patched buffer and whether the decomposition is still in progress.
func patchTail(rb *reorderBuffer) bool {
info, p := lastRuneStart(&rb.f, rb.out)
if p == -1 || info.size == 0 {
return true
}
end := p + int(info.size)
extra := len(rb.out) - end
if extra > 0 {
// Potentially allocating memory. However, this only
// happens with ill-formed UTF-8.
x := make([]byte, 0)
x = append(x, rb.out[len(rb.out)-extra:]...)
rb.out = rb.out[:end]
decomposeToLastBoundary(rb)
rb.doFlush()
rb.out = append(rb.out, x...)
return false
}
buf := rb.out[p:]
rb.out = rb.out[:p]
decomposeToLastBoundary(rb)
if s := rb.ss.next(info); s == ssStarter {
rb.doFlush()
rb.ss.first(info)
} else if s == ssOverflow {
rb.doFlush()
rb.insertCGJ()
rb.ss = 0
}
rb.insertUnsafe(inputBytes(buf), 0, info)
return true
}
func appendQuick(rb *reorderBuffer, i int) int {
if rb.nsrc == i {
return i
}
end, _ := rb.f.quickSpan(rb.src, i, rb.nsrc, true)
rb.out = rb.src.appendSlice(rb.out, i, end)
return end
}
// Append returns f(append(out, b...)).
// The buffer out must be nil, empty, or equal to f(out).
func (f Form) Append(out []byte, src ...byte) []byte {
return f.doAppend(out, inputBytes(src), len(src))
}
func (f Form) doAppend(out []byte, src input, n int) []byte {
if n == 0 {
return out
}
ft := formTable[f]
// Attempt to do a quickSpan first so we can avoid initializing the reorderBuffer.
if len(out) == 0 {
p, _ := ft.quickSpan(src, 0, n, true)
out = src.appendSlice(out, 0, p)
if p == n {
return out
}
rb := reorderBuffer{f: *ft, src: src, nsrc: n, out: out, flushF: appendFlush}
return doAppendInner(&rb, p)
}
rb := reorderBuffer{f: *ft, src: src, nsrc: n}
return doAppend(&rb, out, 0)
}
func doAppend(rb *reorderBuffer, out []byte, p int) []byte {
rb.setFlusher(out, appendFlush)
src, n := rb.src, rb.nsrc
doMerge := len(out) > 0
if q := src.skipContinuationBytes(p); q > p {
// Move leading non-starters to destination.
rb.out = src.appendSlice(rb.out, p, q)
p = q
doMerge = patchTail(rb)
}
fd := &rb.f
if doMerge {
var info Properties
if p < n {
info = fd.info(src, p)
if !info.BoundaryBefore() || info.nLeadingNonStarters() > 0 {
if p == 0 {
decomposeToLastBoundary(rb)
}
p = decomposeSegment(rb, p, true)
}
}
if info.size == 0 {
rb.doFlush()
// Append incomplete UTF-8 encoding.
return src.appendSlice(rb.out, p, n)
}
if rb.nrune > 0 {
return doAppendInner(rb, p)
}
}
p = appendQuick(rb, p)
return doAppendInner(rb, p)
}
func doAppendInner(rb *reorderBuffer, p int) []byte {
for n := rb.nsrc; p < n; {
p = decomposeSegment(rb, p, true)
p = appendQuick(rb, p)
}
return rb.out
}
// AppendString returns f(append(out, []byte(s))).
// The buffer out must be nil, empty, or equal to f(out).
func (f Form) AppendString(out []byte, src string) []byte {
return f.doAppend(out, inputString(src), len(src))
}
// QuickSpan returns a boundary n such that b[0:n] == f(b[0:n]).
// It is not guaranteed to return the largest such n.
func (f Form) QuickSpan(b []byte) int {
n, _ := formTable[f].quickSpan(inputBytes(b), 0, len(b), true)
return n
}
// Span implements transform.SpanningTransformer. It returns a boundary n such
// that b[0:n] == f(b[0:n]). It is not guaranteed to return the largest such n.
func (f Form) Span(b []byte, atEOF bool) (n int, err error) {
n, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), atEOF)
if n < len(b) {
if !ok {
err = transform.ErrEndOfSpan
} else {
err = transform.ErrShortSrc
}
}
return n, err
}
// SpanString returns a boundary n such that s[0:n] == f(s[0:n]).
// It is not guaranteed to return the largest such n.
func (f Form) SpanString(s string, atEOF bool) (n int, err error) {
n, ok := formTable[f].quickSpan(inputString(s), 0, len(s), atEOF)
if n < len(s) {
if !ok {
err = transform.ErrEndOfSpan
} else {
err = transform.ErrShortSrc
}
}
return n, err
}
// quickSpan returns a boundary n such that src[0:n] == f(src[0:n]) and
// whether any non-normalized parts were found. If atEOF is false, n will
// not point past the last segment if this segment might be become
// non-normalized by appending other runes.
func (f *formInfo) quickSpan(src input, i, end int, atEOF bool) (n int, ok bool) {
var lastCC uint8
ss := streamSafe(0)
lastSegStart := i
for n = end; i < n; {
if j := src.skipASCII(i, n); i != j {
i = j
lastSegStart = i - 1
lastCC = 0
ss = 0
continue
}
info := f.info(src, i)
if info.size == 0 {
if atEOF {
// include incomplete runes
return n, true
}
return lastSegStart, true
}
// This block needs to be before the next, because it is possible to
// have an overflow for runes that are starters (e.g. with U+FF9E).
switch ss.next(info) {
case ssStarter:
lastSegStart = i
case ssOverflow:
return lastSegStart, false
case ssSuccess:
if lastCC > info.ccc {
return lastSegStart, false
}
}
if f.composing {
if !info.isYesC() {
break
}
} else {
if !info.isYesD() {
break
}
}
lastCC = info.ccc
i += int(info.size)
}
if i == n {
if !atEOF {
n = lastSegStart
}
return n, true
}
return lastSegStart, false
}
// QuickSpanString returns a boundary n such that s[0:n] == f(s[0:n]).
// It is not guaranteed to return the largest such n.
func (f Form) QuickSpanString(s string) int {
n, _ := formTable[f].quickSpan(inputString(s), 0, len(s), true)
return n
}
// FirstBoundary returns the position i of the first boundary in b
// or -1 if b contains no boundary.
func (f Form) FirstBoundary(b []byte) int {
return f.firstBoundary(inputBytes(b), len(b))
}
func (f Form) firstBoundary(src input, nsrc int) int {
i := src.skipContinuationBytes(0)
if i >= nsrc {
return -1
}
fd := formTable[f]
ss := streamSafe(0)
// We should call ss.first here, but we can't as the first rune is
// skipped already. This means FirstBoundary can't really determine
// CGJ insertion points correctly. Luckily it doesn't have to.
for {
info := fd.info(src, i)
if info.size == 0 {
return -1
}
if s := ss.next(info); s != ssSuccess {
return i
}
i += int(info.size)
if i >= nsrc {
if !info.BoundaryAfter() && !ss.isMax() {
return -1
}
return nsrc
}
}
}
// FirstBoundaryInString returns the position i of the first boundary in s
// or -1 if s contains no boundary.
func (f Form) FirstBoundaryInString(s string) int {
return f.firstBoundary(inputString(s), len(s))
}
// NextBoundary reports the index of the boundary between the first and next
// segment in b or -1 if atEOF is false and there are not enough bytes to
// determine this boundary.
func (f Form) NextBoundary(b []byte, atEOF bool) int {
return f.nextBoundary(inputBytes(b), len(b), atEOF)
}
// NextBoundaryInString reports the index of the boundary between the first and
// next segment in b or -1 if atEOF is false and there are not enough bytes to
// determine this boundary.
func (f Form) NextBoundaryInString(s string, atEOF bool) int {
return f.nextBoundary(inputString(s), len(s), atEOF)
}
func (f Form) nextBoundary(src input, nsrc int, atEOF bool) int {
if nsrc == 0 {
if atEOF {
return 0
}
return -1
}
fd := formTable[f]
info := fd.info(src, 0)
if info.size == 0 {
if atEOF {
return 1
}
return -1
}
ss := streamSafe(0)
ss.first(info)
for i := int(info.size); i < nsrc; i += int(info.size) {
info = fd.info(src, i)
if info.size == 0 {
if atEOF {
return i
}
return -1
}
// TODO: Using streamSafe to determine the boundary isn't the same as
// using BoundaryBefore. Determine which should be used.
if s := ss.next(info); s != ssSuccess {
return i
}
}
if !atEOF && !info.BoundaryAfter() && !ss.isMax() {
return -1
}
return nsrc
}
// LastBoundary returns the position i of the last boundary in b
// or -1 if b contains no boundary.
func (f Form) LastBoundary(b []byte) int {
return lastBoundary(formTable[f], b)
}
func lastBoundary(fd *formInfo, b []byte) int {
i := len(b)
info, p := lastRuneStart(fd, b)
if p == -1 {
return -1
}
if info.size == 0 { // ends with incomplete rune
if p == 0 { // starts with incomplete rune
return -1
}
i = p
info, p = lastRuneStart(fd, b[:i])
if p == -1 { // incomplete UTF-8 encoding or non-starter bytes without a starter
return i
}
}
if p+int(info.size) != i { // trailing non-starter bytes: illegal UTF-8
return i
}
if info.BoundaryAfter() {
return i
}
ss := streamSafe(0)
v := ss.backwards(info)
for i = p; i >= 0 && v != ssStarter; i = p {
info, p = lastRuneStart(fd, b[:i])
if v = ss.backwards(info); v == ssOverflow {
break
}
if p+int(info.size) != i {
if p == -1 { // no boundary found
return -1
}
return i // boundary after an illegal UTF-8 encoding
}
}
return i
}
// decomposeSegment scans the first segment in src into rb. It inserts 0x034f
// (Grapheme Joiner) when it encounters a sequence of more than 30 non-starters
// and returns the number of bytes consumed from src or iShortDst or iShortSrc.
func decomposeSegment(rb *reorderBuffer, sp int, atEOF bool) int {
// Force one character to be consumed.
info := rb.f.info(rb.src, sp)
if info.size == 0 {
return 0
}
if s := rb.ss.next(info); s == ssStarter {
// TODO: this could be removed if we don't support merging.
if rb.nrune > 0 {
goto end
}
} else if s == ssOverflow {
rb.insertCGJ()
goto end
}
if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
return int(err)
}
for {
sp += int(info.size)
if sp >= rb.nsrc {
if !atEOF && !info.BoundaryAfter() {
return int(iShortSrc)
}
break
}
info = rb.f.info(rb.src, sp)
if info.size == 0 {
if !atEOF {
return int(iShortSrc)
}
break
}
if s := rb.ss.next(info); s == ssStarter {
break
} else if s == ssOverflow {
rb.insertCGJ()
break
}
if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
return int(err)
}
}
end:
if !rb.doFlush() {
return int(iShortDst)
}
return sp
}
// lastRuneStart returns the runeInfo and position of the last
// rune in buf or the zero runeInfo and -1 if no rune was found.
func lastRuneStart(fd *formInfo, buf []byte) (Properties, int) {
p := len(buf) - 1
for ; p >= 0 && !utf8.RuneStart(buf[p]); p-- {
}
if p < 0 {
return Properties{}, -1
}
return fd.info(inputBytes(buf), p), p
}
// decomposeToLastBoundary finds an open segment at the end of the buffer
// and scans it into rb. Returns the buffer minus the last segment.
func decomposeToLastBoundary(rb *reorderBuffer) {
fd := &rb.f
info, i := lastRuneStart(fd, rb.out)
if int(info.size) != len(rb.out)-i {
// illegal trailing continuation bytes
return
}
if info.BoundaryAfter() {
return
}
var add [maxNonStarters + 1]Properties // stores runeInfo in reverse order
padd := 0
ss := streamSafe(0)
p := len(rb.out)
for {
add[padd] = info
v := ss.backwards(info)
if v == ssOverflow {
// Note that if we have an overflow, it the string we are appending to
// is not correctly normalized. In this case the behavior is undefined.
break
}
padd++
p -= int(info.size)
if v == ssStarter || p < 0 {
break
}
info, i = lastRuneStart(fd, rb.out[:p])
if int(info.size) != p-i {
break
}
}
rb.ss = ss
// Copy bytes for insertion as we may need to overwrite rb.out.
var buf [maxBufferSize * utf8.UTFMax]byte
cp := buf[:copy(buf[:], rb.out[p:])]
rb.out = rb.out[:p]
for padd--; padd >= 0; padd-- {
info = add[padd]
rb.insertUnsafe(inputBytes(cp), 0, info)
cp = cp[info.size:]
}
}
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
import "io"
type normWriter struct {
rb reorderBuffer
w io.Writer
buf []byte
}
// Write implements the standard write interface. If the last characters are
// not at a normalization boundary, the bytes will be buffered for the next
// write. The remaining bytes will be written on close.
func (w *normWriter) Write(data []byte) (n int, err error) {
// Process data in pieces to keep w.buf size bounded.
const chunk = 4000
for len(data) > 0 {
// Normalize into w.buf.
m := len(data)
if m > chunk {
m = chunk
}
w.rb.src = inputBytes(data[:m])
w.rb.nsrc = m
w.buf = doAppend(&w.rb, w.buf, 0)
data = data[m:]
n += m
// Write out complete prefix, save remainder.
// Note that lastBoundary looks back at most 31 runes.
i := lastBoundary(&w.rb.f, w.buf)
if i == -1 {
i = 0
}
if i > 0 {
if _, err = w.w.Write(w.buf[:i]); err != nil {
break
}
bn := copy(w.buf, w.buf[i:])
w.buf = w.buf[:bn]
}
}
return n, err
}
// Close forces data that remains in the buffer to be written.
func (w *normWriter) Close() error {
if len(w.buf) > 0 {
_, err := w.w.Write(w.buf)
if err != nil {
return err
}
}
return nil
}
// Writer returns a new writer that implements Write(b)
// by writing f(b) to w. The returned writer may use an
// internal buffer to maintain state across Write calls.
// Calling its Close method writes any buffered data to w.
func (f Form) Writer(w io.Writer) io.WriteCloser {
wr := &normWriter{rb: reorderBuffer{}, w: w}
wr.rb.init(f, nil)
return wr
}
type normReader struct {
rb reorderBuffer
r io.Reader
inbuf []byte
outbuf []byte
bufStart int
lastBoundary int
err error
}
// Read implements the standard read interface.
func (r *normReader) Read(p []byte) (int, error) {
for {
if r.lastBoundary-r.bufStart > 0 {
n := copy(p, r.outbuf[r.bufStart:r.lastBoundary])
r.bufStart += n
if r.lastBoundary-r.bufStart > 0 {
return n, nil
}
return n, r.err
}
if r.err != nil {
return 0, r.err
}
outn := copy(r.outbuf, r.outbuf[r.lastBoundary:])
r.outbuf = r.outbuf[0:outn]
r.bufStart = 0
n, err := r.r.Read(r.inbuf)
r.rb.src = inputBytes(r.inbuf[0:n])
r.rb.nsrc, r.err = n, err
if n > 0 {
r.outbuf = doAppend(&r.rb, r.outbuf, 0)
}
if err == io.EOF {
r.lastBoundary = len(r.outbuf)
} else {
r.lastBoundary = lastBoundary(&r.rb.f, r.outbuf)
if r.lastBoundary == -1 {
r.lastBoundary = 0
}
}
}
}
// Reader returns a new reader that implements Read
// by reading data from r and returning f(data).
func (f Form) Reader(r io.Reader) io.Reader {
const chunk = 4000
buf := make([]byte, chunk)
rr := &normReader{rb: reorderBuffer{}, r: r, inbuf: buf}
rr.rb.init(f, buf)
return rr
}
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// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
import (
"unicode/utf8"
"golang.org/x/text/transform"
)
// Reset implements the Reset method of the transform.Transformer interface.
func (Form) Reset() {}
// Transform implements the Transform method of the transform.Transformer
// interface. It may need to write segments of up to MaxSegmentSize at once.
// Users should either catch ErrShortDst and allow dst to grow or have dst be at
// least of size MaxTransformChunkSize to be guaranteed of progress.
func (f Form) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
// Cap the maximum number of src bytes to check.
b := src
eof := atEOF
if ns := len(dst); ns < len(b) {
err = transform.ErrShortDst
eof = false
b = b[:ns]
}
i, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), eof)
n := copy(dst, b[:i])
if !ok {
nDst, nSrc, err = f.transform(dst[n:], src[n:], atEOF)
return nDst + n, nSrc + n, err
}
if err == nil && n < len(src) && !atEOF {
err = transform.ErrShortSrc
}
return n, n, err
}
func flushTransform(rb *reorderBuffer) bool {
// Write out (must fully fit in dst, or else it is an ErrShortDst).
if len(rb.out) < rb.nrune*utf8.UTFMax {
return false
}
rb.out = rb.out[rb.flushCopy(rb.out):]
return true
}
var errs = []error{nil, transform.ErrShortDst, transform.ErrShortSrc}
// transform implements the transform.Transformer interface. It is only called
// when quickSpan does not pass for a given string.
func (f Form) transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
// TODO: get rid of reorderBuffer. See CL 23460044.
rb := reorderBuffer{}
rb.init(f, src)
for {
// Load segment into reorder buffer.
rb.setFlusher(dst[nDst:], flushTransform)
end := decomposeSegment(&rb, nSrc, atEOF)
if end < 0 {
return nDst, nSrc, errs[-end]
}
nDst = len(dst) - len(rb.out)
nSrc = end
// Next quickSpan.
end = rb.nsrc
eof := atEOF
if n := nSrc + len(dst) - nDst; n < end {
err = transform.ErrShortDst
end = n
eof = false
}
end, ok := rb.f.quickSpan(rb.src, nSrc, end, eof)
n := copy(dst[nDst:], rb.src.bytes[nSrc:end])
nSrc += n
nDst += n
if ok {
if err == nil && n < rb.nsrc && !atEOF {
err = transform.ErrShortSrc
}
return nDst, nSrc, err
}
}
}
+54
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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package norm
type valueRange struct {
value uint16 // header: value:stride
lo, hi byte // header: lo:n
}
type sparseBlocks struct {
values []valueRange
offset []uint16
}
var nfcSparse = sparseBlocks{
values: nfcSparseValues[:],
offset: nfcSparseOffset[:],
}
var nfkcSparse = sparseBlocks{
values: nfkcSparseValues[:],
offset: nfkcSparseOffset[:],
}
var (
nfcData = newNfcTrie(0)
nfkcData = newNfkcTrie(0)
)
// lookupValue determines the type of block n and looks up the value for b.
// For n < t.cutoff, the block is a simple lookup table. Otherwise, the block
// is a list of ranges with an accompanying value. Given a matching range r,
// the value for b is by r.value + (b - r.lo) * stride.
func (t *sparseBlocks) lookup(n uint32, b byte) uint16 {
offset := t.offset[n]
header := t.values[offset]
lo := offset + 1
hi := lo + uint16(header.lo)
for lo < hi {
m := lo + (hi-lo)/2
r := t.values[m]
if r.lo <= b && b <= r.hi {
return r.value + uint16(b-r.lo)*header.value
}
if b < r.lo {
hi = m
} else {
lo = m + 1
}
}
return 0
}