William Kurkian | 6ea97f8 | 2019-03-13 15:51:55 -0400 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2014 gRPC authors. |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | package transport |
| 20 | |
| 21 | import ( |
| 22 | "bufio" |
| 23 | "bytes" |
| 24 | "encoding/base64" |
| 25 | "fmt" |
| 26 | "io" |
| 27 | "math" |
| 28 | "net" |
| 29 | "net/http" |
| 30 | "strconv" |
| 31 | "strings" |
| 32 | "time" |
| 33 | "unicode/utf8" |
| 34 | |
| 35 | "github.com/golang/protobuf/proto" |
| 36 | "golang.org/x/net/http2" |
| 37 | "golang.org/x/net/http2/hpack" |
| 38 | spb "google.golang.org/genproto/googleapis/rpc/status" |
| 39 | "google.golang.org/grpc/codes" |
| 40 | "google.golang.org/grpc/status" |
| 41 | ) |
| 42 | |
| 43 | const ( |
| 44 | // http2MaxFrameLen specifies the max length of a HTTP2 frame. |
| 45 | http2MaxFrameLen = 16384 // 16KB frame |
| 46 | // http://http2.github.io/http2-spec/#SettingValues |
| 47 | http2InitHeaderTableSize = 4096 |
| 48 | // baseContentType is the base content-type for gRPC. This is a valid |
| 49 | // content-type on it's own, but can also include a content-subtype such as |
| 50 | // "proto" as a suffix after "+" or ";". See |
| 51 | // https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests |
| 52 | // for more details. |
| 53 | baseContentType = "application/grpc" |
| 54 | ) |
| 55 | |
| 56 | var ( |
| 57 | clientPreface = []byte(http2.ClientPreface) |
| 58 | http2ErrConvTab = map[http2.ErrCode]codes.Code{ |
| 59 | http2.ErrCodeNo: codes.Internal, |
| 60 | http2.ErrCodeProtocol: codes.Internal, |
| 61 | http2.ErrCodeInternal: codes.Internal, |
| 62 | http2.ErrCodeFlowControl: codes.ResourceExhausted, |
| 63 | http2.ErrCodeSettingsTimeout: codes.Internal, |
| 64 | http2.ErrCodeStreamClosed: codes.Internal, |
| 65 | http2.ErrCodeFrameSize: codes.Internal, |
| 66 | http2.ErrCodeRefusedStream: codes.Unavailable, |
| 67 | http2.ErrCodeCancel: codes.Canceled, |
| 68 | http2.ErrCodeCompression: codes.Internal, |
| 69 | http2.ErrCodeConnect: codes.Internal, |
| 70 | http2.ErrCodeEnhanceYourCalm: codes.ResourceExhausted, |
| 71 | http2.ErrCodeInadequateSecurity: codes.PermissionDenied, |
| 72 | http2.ErrCodeHTTP11Required: codes.Internal, |
| 73 | } |
| 74 | statusCodeConvTab = map[codes.Code]http2.ErrCode{ |
| 75 | codes.Internal: http2.ErrCodeInternal, |
| 76 | codes.Canceled: http2.ErrCodeCancel, |
| 77 | codes.Unavailable: http2.ErrCodeRefusedStream, |
| 78 | codes.ResourceExhausted: http2.ErrCodeEnhanceYourCalm, |
| 79 | codes.PermissionDenied: http2.ErrCodeInadequateSecurity, |
| 80 | } |
| 81 | httpStatusConvTab = map[int]codes.Code{ |
| 82 | // 400 Bad Request - INTERNAL. |
| 83 | http.StatusBadRequest: codes.Internal, |
| 84 | // 401 Unauthorized - UNAUTHENTICATED. |
| 85 | http.StatusUnauthorized: codes.Unauthenticated, |
| 86 | // 403 Forbidden - PERMISSION_DENIED. |
| 87 | http.StatusForbidden: codes.PermissionDenied, |
| 88 | // 404 Not Found - UNIMPLEMENTED. |
| 89 | http.StatusNotFound: codes.Unimplemented, |
| 90 | // 429 Too Many Requests - UNAVAILABLE. |
| 91 | http.StatusTooManyRequests: codes.Unavailable, |
| 92 | // 502 Bad Gateway - UNAVAILABLE. |
| 93 | http.StatusBadGateway: codes.Unavailable, |
| 94 | // 503 Service Unavailable - UNAVAILABLE. |
| 95 | http.StatusServiceUnavailable: codes.Unavailable, |
| 96 | // 504 Gateway timeout - UNAVAILABLE. |
| 97 | http.StatusGatewayTimeout: codes.Unavailable, |
| 98 | } |
| 99 | ) |
| 100 | |
| 101 | // Records the states during HPACK decoding. Must be reset once the |
| 102 | // decoding of the entire headers are finished. |
| 103 | type decodeState struct { |
| 104 | encoding string |
| 105 | // statusGen caches the stream status received from the trailer the server |
| 106 | // sent. Client side only. Do not access directly. After all trailers are |
| 107 | // parsed, use the status method to retrieve the status. |
| 108 | statusGen *status.Status |
| 109 | // rawStatusCode and rawStatusMsg are set from the raw trailer fields and are not |
| 110 | // intended for direct access outside of parsing. |
| 111 | rawStatusCode *int |
| 112 | rawStatusMsg string |
| 113 | httpStatus *int |
| 114 | // Server side only fields. |
| 115 | timeoutSet bool |
| 116 | timeout time.Duration |
| 117 | method string |
| 118 | // key-value metadata map from the peer. |
| 119 | mdata map[string][]string |
| 120 | statsTags []byte |
| 121 | statsTrace []byte |
| 122 | contentSubtype string |
| 123 | // whether decoding on server side or not |
| 124 | serverSide bool |
| 125 | } |
| 126 | |
| 127 | // isReservedHeader checks whether hdr belongs to HTTP2 headers |
| 128 | // reserved by gRPC protocol. Any other headers are classified as the |
| 129 | // user-specified metadata. |
| 130 | func isReservedHeader(hdr string) bool { |
| 131 | if hdr != "" && hdr[0] == ':' { |
| 132 | return true |
| 133 | } |
| 134 | switch hdr { |
| 135 | case "content-type", |
| 136 | "user-agent", |
| 137 | "grpc-message-type", |
| 138 | "grpc-encoding", |
| 139 | "grpc-message", |
| 140 | "grpc-status", |
| 141 | "grpc-timeout", |
| 142 | "grpc-status-details-bin", |
| 143 | // Intentionally exclude grpc-previous-rpc-attempts and |
| 144 | // grpc-retry-pushback-ms, which are "reserved", but their API |
| 145 | // intentionally works via metadata. |
| 146 | "te": |
| 147 | return true |
| 148 | default: |
| 149 | return false |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | // isWhitelistedHeader checks whether hdr should be propagated into metadata |
| 154 | // visible to users, even though it is classified as "reserved", above. |
| 155 | func isWhitelistedHeader(hdr string) bool { |
| 156 | switch hdr { |
| 157 | case ":authority", "user-agent": |
| 158 | return true |
| 159 | default: |
| 160 | return false |
| 161 | } |
| 162 | } |
| 163 | |
| 164 | // contentSubtype returns the content-subtype for the given content-type. The |
| 165 | // given content-type must be a valid content-type that starts with |
| 166 | // "application/grpc". A content-subtype will follow "application/grpc" after a |
| 167 | // "+" or ";". See |
| 168 | // https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for |
| 169 | // more details. |
| 170 | // |
| 171 | // If contentType is not a valid content-type for gRPC, the boolean |
| 172 | // will be false, otherwise true. If content-type == "application/grpc", |
| 173 | // "application/grpc+", or "application/grpc;", the boolean will be true, |
| 174 | // but no content-subtype will be returned. |
| 175 | // |
| 176 | // contentType is assumed to be lowercase already. |
| 177 | func contentSubtype(contentType string) (string, bool) { |
| 178 | if contentType == baseContentType { |
| 179 | return "", true |
| 180 | } |
| 181 | if !strings.HasPrefix(contentType, baseContentType) { |
| 182 | return "", false |
| 183 | } |
| 184 | // guaranteed since != baseContentType and has baseContentType prefix |
| 185 | switch contentType[len(baseContentType)] { |
| 186 | case '+', ';': |
| 187 | // this will return true for "application/grpc+" or "application/grpc;" |
| 188 | // which the previous validContentType function tested to be valid, so we |
| 189 | // just say that no content-subtype is specified in this case |
| 190 | return contentType[len(baseContentType)+1:], true |
| 191 | default: |
| 192 | return "", false |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | // contentSubtype is assumed to be lowercase |
| 197 | func contentType(contentSubtype string) string { |
| 198 | if contentSubtype == "" { |
| 199 | return baseContentType |
| 200 | } |
| 201 | return baseContentType + "+" + contentSubtype |
| 202 | } |
| 203 | |
| 204 | func (d *decodeState) status() *status.Status { |
| 205 | if d.statusGen == nil { |
| 206 | // No status-details were provided; generate status using code/msg. |
| 207 | d.statusGen = status.New(codes.Code(int32(*(d.rawStatusCode))), d.rawStatusMsg) |
| 208 | } |
| 209 | return d.statusGen |
| 210 | } |
| 211 | |
| 212 | const binHdrSuffix = "-bin" |
| 213 | |
| 214 | func encodeBinHeader(v []byte) string { |
| 215 | return base64.RawStdEncoding.EncodeToString(v) |
| 216 | } |
| 217 | |
| 218 | func decodeBinHeader(v string) ([]byte, error) { |
| 219 | if len(v)%4 == 0 { |
| 220 | // Input was padded, or padding was not necessary. |
| 221 | return base64.StdEncoding.DecodeString(v) |
| 222 | } |
| 223 | return base64.RawStdEncoding.DecodeString(v) |
| 224 | } |
| 225 | |
| 226 | func encodeMetadataHeader(k, v string) string { |
| 227 | if strings.HasSuffix(k, binHdrSuffix) { |
| 228 | return encodeBinHeader(([]byte)(v)) |
| 229 | } |
| 230 | return v |
| 231 | } |
| 232 | |
| 233 | func decodeMetadataHeader(k, v string) (string, error) { |
| 234 | if strings.HasSuffix(k, binHdrSuffix) { |
| 235 | b, err := decodeBinHeader(v) |
| 236 | return string(b), err |
| 237 | } |
| 238 | return v, nil |
| 239 | } |
| 240 | |
| 241 | func (d *decodeState) decodeHeader(frame *http2.MetaHeadersFrame) error { |
| 242 | // frame.Truncated is set to true when framer detects that the current header |
| 243 | // list size hits MaxHeaderListSize limit. |
| 244 | if frame.Truncated { |
| 245 | return status.Error(codes.Internal, "peer header list size exceeded limit") |
| 246 | } |
| 247 | for _, hf := range frame.Fields { |
| 248 | if err := d.processHeaderField(hf); err != nil { |
| 249 | return err |
| 250 | } |
| 251 | } |
| 252 | |
| 253 | if d.serverSide { |
| 254 | return nil |
| 255 | } |
| 256 | |
| 257 | // If grpc status exists, no need to check further. |
| 258 | if d.rawStatusCode != nil || d.statusGen != nil { |
| 259 | return nil |
| 260 | } |
| 261 | |
| 262 | // If grpc status doesn't exist and http status doesn't exist, |
| 263 | // then it's a malformed header. |
| 264 | if d.httpStatus == nil { |
| 265 | return status.Error(codes.Internal, "malformed header: doesn't contain status(gRPC or HTTP)") |
| 266 | } |
| 267 | |
| 268 | if *(d.httpStatus) != http.StatusOK { |
| 269 | code, ok := httpStatusConvTab[*(d.httpStatus)] |
| 270 | if !ok { |
| 271 | code = codes.Unknown |
| 272 | } |
| 273 | return status.Error(code, http.StatusText(*(d.httpStatus))) |
| 274 | } |
| 275 | |
| 276 | // gRPC status doesn't exist and http status is OK. |
| 277 | // Set rawStatusCode to be unknown and return nil error. |
| 278 | // So that, if the stream has ended this Unknown status |
| 279 | // will be propagated to the user. |
| 280 | // Otherwise, it will be ignored. In which case, status from |
| 281 | // a later trailer, that has StreamEnded flag set, is propagated. |
| 282 | code := int(codes.Unknown) |
| 283 | d.rawStatusCode = &code |
| 284 | return nil |
| 285 | } |
| 286 | |
| 287 | func (d *decodeState) addMetadata(k, v string) { |
| 288 | if d.mdata == nil { |
| 289 | d.mdata = make(map[string][]string) |
| 290 | } |
| 291 | d.mdata[k] = append(d.mdata[k], v) |
| 292 | } |
| 293 | |
| 294 | func (d *decodeState) processHeaderField(f hpack.HeaderField) error { |
| 295 | switch f.Name { |
| 296 | case "content-type": |
| 297 | contentSubtype, validContentType := contentSubtype(f.Value) |
| 298 | if !validContentType { |
| 299 | return status.Errorf(codes.Internal, "transport: received the unexpected content-type %q", f.Value) |
| 300 | } |
| 301 | d.contentSubtype = contentSubtype |
| 302 | // TODO: do we want to propagate the whole content-type in the metadata, |
| 303 | // or come up with a way to just propagate the content-subtype if it was set? |
| 304 | // ie {"content-type": "application/grpc+proto"} or {"content-subtype": "proto"} |
| 305 | // in the metadata? |
| 306 | d.addMetadata(f.Name, f.Value) |
| 307 | case "grpc-encoding": |
| 308 | d.encoding = f.Value |
| 309 | case "grpc-status": |
| 310 | code, err := strconv.Atoi(f.Value) |
| 311 | if err != nil { |
| 312 | return status.Errorf(codes.Internal, "transport: malformed grpc-status: %v", err) |
| 313 | } |
| 314 | d.rawStatusCode = &code |
| 315 | case "grpc-message": |
| 316 | d.rawStatusMsg = decodeGrpcMessage(f.Value) |
| 317 | case "grpc-status-details-bin": |
| 318 | v, err := decodeBinHeader(f.Value) |
| 319 | if err != nil { |
| 320 | return status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err) |
| 321 | } |
| 322 | s := &spb.Status{} |
| 323 | if err := proto.Unmarshal(v, s); err != nil { |
| 324 | return status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err) |
| 325 | } |
| 326 | d.statusGen = status.FromProto(s) |
| 327 | case "grpc-timeout": |
| 328 | d.timeoutSet = true |
| 329 | var err error |
| 330 | if d.timeout, err = decodeTimeout(f.Value); err != nil { |
| 331 | return status.Errorf(codes.Internal, "transport: malformed time-out: %v", err) |
| 332 | } |
| 333 | case ":path": |
| 334 | d.method = f.Value |
| 335 | case ":status": |
| 336 | code, err := strconv.Atoi(f.Value) |
| 337 | if err != nil { |
| 338 | return status.Errorf(codes.Internal, "transport: malformed http-status: %v", err) |
| 339 | } |
| 340 | d.httpStatus = &code |
| 341 | case "grpc-tags-bin": |
| 342 | v, err := decodeBinHeader(f.Value) |
| 343 | if err != nil { |
| 344 | return status.Errorf(codes.Internal, "transport: malformed grpc-tags-bin: %v", err) |
| 345 | } |
| 346 | d.statsTags = v |
| 347 | d.addMetadata(f.Name, string(v)) |
| 348 | case "grpc-trace-bin": |
| 349 | v, err := decodeBinHeader(f.Value) |
| 350 | if err != nil { |
| 351 | return status.Errorf(codes.Internal, "transport: malformed grpc-trace-bin: %v", err) |
| 352 | } |
| 353 | d.statsTrace = v |
| 354 | d.addMetadata(f.Name, string(v)) |
| 355 | default: |
| 356 | if isReservedHeader(f.Name) && !isWhitelistedHeader(f.Name) { |
| 357 | break |
| 358 | } |
| 359 | v, err := decodeMetadataHeader(f.Name, f.Value) |
| 360 | if err != nil { |
| 361 | errorf("Failed to decode metadata header (%q, %q): %v", f.Name, f.Value, err) |
| 362 | return nil |
| 363 | } |
| 364 | d.addMetadata(f.Name, v) |
| 365 | } |
| 366 | return nil |
| 367 | } |
| 368 | |
| 369 | type timeoutUnit uint8 |
| 370 | |
| 371 | const ( |
| 372 | hour timeoutUnit = 'H' |
| 373 | minute timeoutUnit = 'M' |
| 374 | second timeoutUnit = 'S' |
| 375 | millisecond timeoutUnit = 'm' |
| 376 | microsecond timeoutUnit = 'u' |
| 377 | nanosecond timeoutUnit = 'n' |
| 378 | ) |
| 379 | |
| 380 | func timeoutUnitToDuration(u timeoutUnit) (d time.Duration, ok bool) { |
| 381 | switch u { |
| 382 | case hour: |
| 383 | return time.Hour, true |
| 384 | case minute: |
| 385 | return time.Minute, true |
| 386 | case second: |
| 387 | return time.Second, true |
| 388 | case millisecond: |
| 389 | return time.Millisecond, true |
| 390 | case microsecond: |
| 391 | return time.Microsecond, true |
| 392 | case nanosecond: |
| 393 | return time.Nanosecond, true |
| 394 | default: |
| 395 | } |
| 396 | return |
| 397 | } |
| 398 | |
| 399 | const maxTimeoutValue int64 = 100000000 - 1 |
| 400 | |
| 401 | // div does integer division and round-up the result. Note that this is |
| 402 | // equivalent to (d+r-1)/r but has less chance to overflow. |
| 403 | func div(d, r time.Duration) int64 { |
| 404 | if m := d % r; m > 0 { |
| 405 | return int64(d/r + 1) |
| 406 | } |
| 407 | return int64(d / r) |
| 408 | } |
| 409 | |
| 410 | // TODO(zhaoq): It is the simplistic and not bandwidth efficient. Improve it. |
| 411 | func encodeTimeout(t time.Duration) string { |
| 412 | if t <= 0 { |
| 413 | return "0n" |
| 414 | } |
| 415 | if d := div(t, time.Nanosecond); d <= maxTimeoutValue { |
| 416 | return strconv.FormatInt(d, 10) + "n" |
| 417 | } |
| 418 | if d := div(t, time.Microsecond); d <= maxTimeoutValue { |
| 419 | return strconv.FormatInt(d, 10) + "u" |
| 420 | } |
| 421 | if d := div(t, time.Millisecond); d <= maxTimeoutValue { |
| 422 | return strconv.FormatInt(d, 10) + "m" |
| 423 | } |
| 424 | if d := div(t, time.Second); d <= maxTimeoutValue { |
| 425 | return strconv.FormatInt(d, 10) + "S" |
| 426 | } |
| 427 | if d := div(t, time.Minute); d <= maxTimeoutValue { |
| 428 | return strconv.FormatInt(d, 10) + "M" |
| 429 | } |
| 430 | // Note that maxTimeoutValue * time.Hour > MaxInt64. |
| 431 | return strconv.FormatInt(div(t, time.Hour), 10) + "H" |
| 432 | } |
| 433 | |
| 434 | func decodeTimeout(s string) (time.Duration, error) { |
| 435 | size := len(s) |
| 436 | if size < 2 { |
| 437 | return 0, fmt.Errorf("transport: timeout string is too short: %q", s) |
| 438 | } |
| 439 | if size > 9 { |
| 440 | // Spec allows for 8 digits plus the unit. |
| 441 | return 0, fmt.Errorf("transport: timeout string is too long: %q", s) |
| 442 | } |
| 443 | unit := timeoutUnit(s[size-1]) |
| 444 | d, ok := timeoutUnitToDuration(unit) |
| 445 | if !ok { |
| 446 | return 0, fmt.Errorf("transport: timeout unit is not recognized: %q", s) |
| 447 | } |
| 448 | t, err := strconv.ParseInt(s[:size-1], 10, 64) |
| 449 | if err != nil { |
| 450 | return 0, err |
| 451 | } |
| 452 | const maxHours = math.MaxInt64 / int64(time.Hour) |
| 453 | if d == time.Hour && t > maxHours { |
| 454 | // This timeout would overflow math.MaxInt64; clamp it. |
| 455 | return time.Duration(math.MaxInt64), nil |
| 456 | } |
| 457 | return d * time.Duration(t), nil |
| 458 | } |
| 459 | |
| 460 | const ( |
| 461 | spaceByte = ' ' |
| 462 | tildeByte = '~' |
| 463 | percentByte = '%' |
| 464 | ) |
| 465 | |
| 466 | // encodeGrpcMessage is used to encode status code in header field |
| 467 | // "grpc-message". It does percent encoding and also replaces invalid utf-8 |
| 468 | // characters with Unicode replacement character. |
| 469 | // |
| 470 | // It checks to see if each individual byte in msg is an allowable byte, and |
| 471 | // then either percent encoding or passing it through. When percent encoding, |
| 472 | // the byte is converted into hexadecimal notation with a '%' prepended. |
| 473 | func encodeGrpcMessage(msg string) string { |
| 474 | if msg == "" { |
| 475 | return "" |
| 476 | } |
| 477 | lenMsg := len(msg) |
| 478 | for i := 0; i < lenMsg; i++ { |
| 479 | c := msg[i] |
| 480 | if !(c >= spaceByte && c <= tildeByte && c != percentByte) { |
| 481 | return encodeGrpcMessageUnchecked(msg) |
| 482 | } |
| 483 | } |
| 484 | return msg |
| 485 | } |
| 486 | |
| 487 | func encodeGrpcMessageUnchecked(msg string) string { |
| 488 | var buf bytes.Buffer |
| 489 | for len(msg) > 0 { |
| 490 | r, size := utf8.DecodeRuneInString(msg) |
| 491 | for _, b := range []byte(string(r)) { |
| 492 | if size > 1 { |
| 493 | // If size > 1, r is not ascii. Always do percent encoding. |
| 494 | buf.WriteString(fmt.Sprintf("%%%02X", b)) |
| 495 | continue |
| 496 | } |
| 497 | |
| 498 | // The for loop is necessary even if size == 1. r could be |
| 499 | // utf8.RuneError. |
| 500 | // |
| 501 | // fmt.Sprintf("%%%02X", utf8.RuneError) gives "%FFFD". |
| 502 | if b >= spaceByte && b <= tildeByte && b != percentByte { |
| 503 | buf.WriteByte(b) |
| 504 | } else { |
| 505 | buf.WriteString(fmt.Sprintf("%%%02X", b)) |
| 506 | } |
| 507 | } |
| 508 | msg = msg[size:] |
| 509 | } |
| 510 | return buf.String() |
| 511 | } |
| 512 | |
| 513 | // decodeGrpcMessage decodes the msg encoded by encodeGrpcMessage. |
| 514 | func decodeGrpcMessage(msg string) string { |
| 515 | if msg == "" { |
| 516 | return "" |
| 517 | } |
| 518 | lenMsg := len(msg) |
| 519 | for i := 0; i < lenMsg; i++ { |
| 520 | if msg[i] == percentByte && i+2 < lenMsg { |
| 521 | return decodeGrpcMessageUnchecked(msg) |
| 522 | } |
| 523 | } |
| 524 | return msg |
| 525 | } |
| 526 | |
| 527 | func decodeGrpcMessageUnchecked(msg string) string { |
| 528 | var buf bytes.Buffer |
| 529 | lenMsg := len(msg) |
| 530 | for i := 0; i < lenMsg; i++ { |
| 531 | c := msg[i] |
| 532 | if c == percentByte && i+2 < lenMsg { |
| 533 | parsed, err := strconv.ParseUint(msg[i+1:i+3], 16, 8) |
| 534 | if err != nil { |
| 535 | buf.WriteByte(c) |
| 536 | } else { |
| 537 | buf.WriteByte(byte(parsed)) |
| 538 | i += 2 |
| 539 | } |
| 540 | } else { |
| 541 | buf.WriteByte(c) |
| 542 | } |
| 543 | } |
| 544 | return buf.String() |
| 545 | } |
| 546 | |
| 547 | type bufWriter struct { |
| 548 | buf []byte |
| 549 | offset int |
| 550 | batchSize int |
| 551 | conn net.Conn |
| 552 | err error |
| 553 | |
| 554 | onFlush func() |
| 555 | } |
| 556 | |
| 557 | func newBufWriter(conn net.Conn, batchSize int) *bufWriter { |
| 558 | return &bufWriter{ |
| 559 | buf: make([]byte, batchSize*2), |
| 560 | batchSize: batchSize, |
| 561 | conn: conn, |
| 562 | } |
| 563 | } |
| 564 | |
| 565 | func (w *bufWriter) Write(b []byte) (n int, err error) { |
| 566 | if w.err != nil { |
| 567 | return 0, w.err |
| 568 | } |
| 569 | if w.batchSize == 0 { // Buffer has been disabled. |
| 570 | return w.conn.Write(b) |
| 571 | } |
| 572 | for len(b) > 0 { |
| 573 | nn := copy(w.buf[w.offset:], b) |
| 574 | b = b[nn:] |
| 575 | w.offset += nn |
| 576 | n += nn |
| 577 | if w.offset >= w.batchSize { |
| 578 | err = w.Flush() |
| 579 | } |
| 580 | } |
| 581 | return n, err |
| 582 | } |
| 583 | |
| 584 | func (w *bufWriter) Flush() error { |
| 585 | if w.err != nil { |
| 586 | return w.err |
| 587 | } |
| 588 | if w.offset == 0 { |
| 589 | return nil |
| 590 | } |
| 591 | if w.onFlush != nil { |
| 592 | w.onFlush() |
| 593 | } |
| 594 | _, w.err = w.conn.Write(w.buf[:w.offset]) |
| 595 | w.offset = 0 |
| 596 | return w.err |
| 597 | } |
| 598 | |
| 599 | type framer struct { |
| 600 | writer *bufWriter |
| 601 | fr *http2.Framer |
| 602 | } |
| 603 | |
| 604 | func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, maxHeaderListSize uint32) *framer { |
| 605 | if writeBufferSize < 0 { |
| 606 | writeBufferSize = 0 |
| 607 | } |
| 608 | var r io.Reader = conn |
| 609 | if readBufferSize > 0 { |
| 610 | r = bufio.NewReaderSize(r, readBufferSize) |
| 611 | } |
| 612 | w := newBufWriter(conn, writeBufferSize) |
| 613 | f := &framer{ |
| 614 | writer: w, |
| 615 | fr: http2.NewFramer(w, r), |
| 616 | } |
| 617 | // Opt-in to Frame reuse API on framer to reduce garbage. |
| 618 | // Frames aren't safe to read from after a subsequent call to ReadFrame. |
| 619 | f.fr.SetReuseFrames() |
| 620 | f.fr.MaxHeaderListSize = maxHeaderListSize |
| 621 | f.fr.ReadMetaHeaders = hpack.NewDecoder(http2InitHeaderTableSize, nil) |
| 622 | return f |
| 623 | } |