forgejo/cmd/hook.go
Gusted 71e63f541d [BUG] Make delay writer actually work
- Reading the code of this delay writer implemenation, it looks like
that it should only actually write content to the `io.Writer` if x
amount of time has passed by. However in practice it was always printing
the buffer even if the X amount of time didn't pass yet. This is in line
with what was being said in the issue that this was to help with
https://github.com/go-gitea/gitea/issues/9610.
- This was caused by the extra `Close()` calls which in turn caused that
when the second `Close` is called (which is done in a defer already) it
would've printed the buffer anyway. So remove the extra calls to `Close()`.
- Add unit test.

(cherry picked from commit 9320ffd2b5)
2024-04-03 07:34:49 +00:00

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// Copyright 2017 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package cmd
import (
"bufio"
"bytes"
"context"
"fmt"
"io"
"os"
"strconv"
"strings"
"time"
"code.gitea.io/gitea/modules/git"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/private"
repo_module "code.gitea.io/gitea/modules/repository"
"code.gitea.io/gitea/modules/setting"
"github.com/urfave/cli/v2"
)
const (
hookBatchSize = 30
)
var (
// CmdHook represents the available hooks sub-command.
CmdHook = &cli.Command{
Name: "hook",
Usage: "(internal) Should only be called by Git",
Description: "Delegate commands to corresponding Git hooks",
Before: PrepareConsoleLoggerLevel(log.FATAL),
Subcommands: []*cli.Command{
subcmdHookPreReceive,
subcmdHookUpdate,
subcmdHookPostReceive,
subcmdHookProcReceive,
},
}
subcmdHookPreReceive = &cli.Command{
Name: "pre-receive",
Usage: "Delegate pre-receive Git hook",
Description: "This command should only be called by Git",
Action: runHookPreReceive,
Flags: []cli.Flag{
&cli.BoolFlag{
Name: "debug",
},
},
}
subcmdHookUpdate = &cli.Command{
Name: "update",
Usage: "Delegate update Git hook",
Description: "This command should only be called by Git",
Action: runHookUpdate,
Flags: []cli.Flag{
&cli.BoolFlag{
Name: "debug",
},
},
}
subcmdHookPostReceive = &cli.Command{
Name: "post-receive",
Usage: "Delegate post-receive Git hook",
Description: "This command should only be called by Git",
Action: runHookPostReceive,
Flags: []cli.Flag{
&cli.BoolFlag{
Name: "debug",
},
},
}
// Note: new hook since git 2.29
subcmdHookProcReceive = &cli.Command{
Name: "proc-receive",
Usage: "Delegate proc-receive Git hook",
Description: "This command should only be called by Git",
Action: runHookProcReceive,
Flags: []cli.Flag{
&cli.BoolFlag{
Name: "debug",
},
},
}
)
type delayWriter struct {
internal io.Writer
buf *bytes.Buffer
timer *time.Timer
}
func newDelayWriter(internal io.Writer, delay time.Duration) *delayWriter {
timer := time.NewTimer(delay)
return &delayWriter{
internal: internal,
buf: &bytes.Buffer{},
timer: timer,
}
}
func (d *delayWriter) Write(p []byte) (n int, err error) {
if d.buf != nil {
select {
case <-d.timer.C:
_, err := d.internal.Write(d.buf.Bytes())
if err != nil {
return 0, err
}
d.buf = nil
return d.internal.Write(p)
default:
return d.buf.Write(p)
}
}
return d.internal.Write(p)
}
func (d *delayWriter) WriteString(s string) (n int, err error) {
if d.buf != nil {
select {
case <-d.timer.C:
_, err := d.internal.Write(d.buf.Bytes())
if err != nil {
return 0, err
}
d.buf = nil
return d.internal.Write([]byte(s))
default:
return d.buf.WriteString(s)
}
}
return d.internal.Write([]byte(s))
}
func (d *delayWriter) Close() error {
if d == nil {
return nil
}
stopped := d.timer.Stop()
if stopped || d.buf == nil {
return nil
}
_, err := d.internal.Write(d.buf.Bytes())
d.buf = nil
return err
}
type nilWriter struct{}
func (n *nilWriter) Write(p []byte) (int, error) {
return len(p), nil
}
func (n *nilWriter) WriteString(s string) (int, error) {
return len(s), nil
}
func runHookPreReceive(c *cli.Context) error {
if isInternal, _ := strconv.ParseBool(os.Getenv(repo_module.EnvIsInternal)); isInternal {
return nil
}
ctx, cancel := installSignals()
defer cancel()
setup(ctx, c.Bool("debug"))
if len(os.Getenv("SSH_ORIGINAL_COMMAND")) == 0 {
if setting.OnlyAllowPushIfGiteaEnvironmentSet {
return fail(ctx, `Rejecting changes as Forgejo environment not set.
If you are pushing over SSH you must push with a key managed by
Forgejo or set your environment appropriately.`, "")
}
return nil
}
// the environment is set by serv command
isWiki, _ := strconv.ParseBool(os.Getenv(repo_module.EnvRepoIsWiki))
username := os.Getenv(repo_module.EnvRepoUsername)
reponame := os.Getenv(repo_module.EnvRepoName)
userID, _ := strconv.ParseInt(os.Getenv(repo_module.EnvPusherID), 10, 64)
prID, _ := strconv.ParseInt(os.Getenv(repo_module.EnvPRID), 10, 64)
deployKeyID, _ := strconv.ParseInt(os.Getenv(repo_module.EnvDeployKeyID), 10, 64)
actionPerm, _ := strconv.ParseInt(os.Getenv(repo_module.EnvActionPerm), 10, 64)
hookOptions := private.HookOptions{
UserID: userID,
GitAlternativeObjectDirectories: os.Getenv(private.GitAlternativeObjectDirectories),
GitObjectDirectory: os.Getenv(private.GitObjectDirectory),
GitQuarantinePath: os.Getenv(private.GitQuarantinePath),
GitPushOptions: pushOptions(),
PullRequestID: prID,
DeployKeyID: deployKeyID,
ActionPerm: int(actionPerm),
}
scanner := bufio.NewScanner(os.Stdin)
oldCommitIDs := make([]string, hookBatchSize)
newCommitIDs := make([]string, hookBatchSize)
refFullNames := make([]git.RefName, hookBatchSize)
count := 0
total := 0
lastline := 0
var out io.Writer
out = &nilWriter{}
if setting.Git.VerbosePush {
if setting.Git.VerbosePushDelay > 0 {
dWriter := newDelayWriter(os.Stdout, setting.Git.VerbosePushDelay)
defer dWriter.Close()
out = dWriter
} else {
out = os.Stdout
}
}
supportProcReceive := false
if git.CheckGitVersionAtLeast("2.29") == nil {
supportProcReceive = true
}
for scanner.Scan() {
// TODO: support news feeds for wiki
if isWiki {
continue
}
fields := bytes.Fields(scanner.Bytes())
if len(fields) != 3 {
continue
}
oldCommitID := string(fields[0])
newCommitID := string(fields[1])
refFullName := git.RefName(fields[2])
total++
lastline++
// If the ref is a branch or tag, check if it's protected
// if supportProcReceive all ref should be checked because
// permission check was delayed
if supportProcReceive || refFullName.IsBranch() || refFullName.IsTag() {
oldCommitIDs[count] = oldCommitID
newCommitIDs[count] = newCommitID
refFullNames[count] = refFullName
count++
fmt.Fprintf(out, "*")
if count >= hookBatchSize {
fmt.Fprintf(out, " Checking %d references\n", count)
hookOptions.OldCommitIDs = oldCommitIDs
hookOptions.NewCommitIDs = newCommitIDs
hookOptions.RefFullNames = refFullNames
extra := private.HookPreReceive(ctx, username, reponame, hookOptions)
if extra.HasError() {
return fail(ctx, extra.UserMsg, "HookPreReceive(batch) failed: %v", extra.Error)
}
count = 0
lastline = 0
}
} else {
fmt.Fprintf(out, ".")
}
if lastline >= hookBatchSize {
fmt.Fprintf(out, "\n")
lastline = 0
}
}
if count > 0 {
hookOptions.OldCommitIDs = oldCommitIDs[:count]
hookOptions.NewCommitIDs = newCommitIDs[:count]
hookOptions.RefFullNames = refFullNames[:count]
fmt.Fprintf(out, " Checking %d references\n", count)
extra := private.HookPreReceive(ctx, username, reponame, hookOptions)
if extra.HasError() {
return fail(ctx, extra.UserMsg, "HookPreReceive(last) failed: %v", extra.Error)
}
} else if lastline > 0 {
fmt.Fprintf(out, "\n")
}
fmt.Fprintf(out, "Checked %d references in total\n", total)
return nil
}
// runHookUpdate process the update hook: https://git-scm.com/docs/githooks#update
func runHookUpdate(c *cli.Context) error {
// Now if we're an internal don't do anything else
if isInternal, _ := strconv.ParseBool(os.Getenv(repo_module.EnvIsInternal)); isInternal {
return nil
}
ctx, cancel := installSignals()
defer cancel()
// The last three arguments given to the hook are in order: reference name, old commit ID and new commit ID.
args := os.Args[len(os.Args)-3:]
refFullName := git.RefName(args[0])
newCommitID := args[2]
// Only process pull references.
if !refFullName.IsPull() {
return nil
}
// Deletion of the ref means that the new commit ID is only composed of '0'.
if strings.ContainsFunc(newCommitID, func(e rune) bool { return e != '0' }) {
return nil
}
return fail(ctx, fmt.Sprintf("The deletion of %s is skipped as it's an internal reference.", refFullName), "")
}
func runHookPostReceive(c *cli.Context) error {
ctx, cancel := installSignals()
defer cancel()
setup(ctx, c.Bool("debug"))
// First of all run update-server-info no matter what
if _, _, err := git.NewCommand(ctx, "update-server-info").RunStdString(nil); err != nil {
return fmt.Errorf("Failed to call 'git update-server-info': %w", err)
}
// Now if we're an internal don't do anything else
if isInternal, _ := strconv.ParseBool(os.Getenv(repo_module.EnvIsInternal)); isInternal {
return nil
}
if len(os.Getenv("SSH_ORIGINAL_COMMAND")) == 0 {
if setting.OnlyAllowPushIfGiteaEnvironmentSet {
return fail(ctx, `Rejecting changes as Forgejo environment not set.
If you are pushing over SSH you must push with a key managed by
Forgejo or set your environment appropriately.`, "")
}
return nil
}
var out io.Writer
out = &nilWriter{}
if setting.Git.VerbosePush {
if setting.Git.VerbosePushDelay > 0 {
dWriter := newDelayWriter(os.Stdout, setting.Git.VerbosePushDelay)
defer dWriter.Close()
out = dWriter
} else {
out = os.Stdout
}
}
// the environment is set by serv command
repoUser := os.Getenv(repo_module.EnvRepoUsername)
isWiki, _ := strconv.ParseBool(os.Getenv(repo_module.EnvRepoIsWiki))
repoName := os.Getenv(repo_module.EnvRepoName)
pusherID, _ := strconv.ParseInt(os.Getenv(repo_module.EnvPusherID), 10, 64)
pusherName := os.Getenv(repo_module.EnvPusherName)
hookOptions := private.HookOptions{
UserName: pusherName,
UserID: pusherID,
GitAlternativeObjectDirectories: os.Getenv(private.GitAlternativeObjectDirectories),
GitObjectDirectory: os.Getenv(private.GitObjectDirectory),
GitQuarantinePath: os.Getenv(private.GitQuarantinePath),
GitPushOptions: pushOptions(),
}
oldCommitIDs := make([]string, hookBatchSize)
newCommitIDs := make([]string, hookBatchSize)
refFullNames := make([]git.RefName, hookBatchSize)
count := 0
total := 0
wasEmpty := false
masterPushed := false
results := make([]private.HookPostReceiveBranchResult, 0)
scanner := bufio.NewScanner(os.Stdin)
for scanner.Scan() {
// TODO: support news feeds for wiki
if isWiki {
continue
}
fields := bytes.Fields(scanner.Bytes())
if len(fields) != 3 {
continue
}
fmt.Fprintf(out, ".")
oldCommitIDs[count] = string(fields[0])
newCommitIDs[count] = string(fields[1])
refFullNames[count] = git.RefName(fields[2])
commitID, _ := git.NewIDFromString(newCommitIDs[count])
if refFullNames[count] == git.BranchPrefix+"master" && !commitID.IsZero() && count == total {
masterPushed = true
}
count++
total++
if count >= hookBatchSize {
fmt.Fprintf(out, " Processing %d references\n", count)
hookOptions.OldCommitIDs = oldCommitIDs
hookOptions.NewCommitIDs = newCommitIDs
hookOptions.RefFullNames = refFullNames
resp, extra := private.HookPostReceive(ctx, repoUser, repoName, hookOptions)
if extra.HasError() {
hookPrintResults(results)
return fail(ctx, extra.UserMsg, "HookPostReceive failed: %v", extra.Error)
}
wasEmpty = wasEmpty || resp.RepoWasEmpty
results = append(results, resp.Results...)
count = 0
}
}
if count == 0 {
if wasEmpty && masterPushed {
// We need to tell the repo to reset the default branch to master
extra := private.SetDefaultBranch(ctx, repoUser, repoName, "master")
if extra.HasError() {
return fail(ctx, extra.UserMsg, "SetDefaultBranch failed: %v", extra.Error)
}
}
fmt.Fprintf(out, "Processed %d references in total\n", total)
hookPrintResults(results)
return nil
}
hookOptions.OldCommitIDs = oldCommitIDs[:count]
hookOptions.NewCommitIDs = newCommitIDs[:count]
hookOptions.RefFullNames = refFullNames[:count]
fmt.Fprintf(out, " Processing %d references\n", count)
resp, extra := private.HookPostReceive(ctx, repoUser, repoName, hookOptions)
if resp == nil {
hookPrintResults(results)
return fail(ctx, extra.UserMsg, "HookPostReceive failed: %v", extra.Error)
}
wasEmpty = wasEmpty || resp.RepoWasEmpty
results = append(results, resp.Results...)
fmt.Fprintf(out, "Processed %d references in total\n", total)
if wasEmpty && masterPushed {
// We need to tell the repo to reset the default branch to master
extra := private.SetDefaultBranch(ctx, repoUser, repoName, "master")
if extra.HasError() {
return fail(ctx, extra.UserMsg, "SetDefaultBranch failed: %v", extra.Error)
}
}
hookPrintResults(results)
return nil
}
func hookPrintResults(results []private.HookPostReceiveBranchResult) {
for _, res := range results {
if !res.Message {
continue
}
fmt.Fprintln(os.Stderr, "")
if res.Create {
fmt.Fprintf(os.Stderr, "Create a new pull request for '%s':\n", res.Branch)
fmt.Fprintf(os.Stderr, " %s\n", res.URL)
} else {
fmt.Fprint(os.Stderr, "Visit the existing pull request:\n")
fmt.Fprintf(os.Stderr, " %s\n", res.URL)
}
fmt.Fprintln(os.Stderr, "")
os.Stderr.Sync()
}
}
func pushOptions() map[string]string {
opts := make(map[string]string)
if pushCount, err := strconv.Atoi(os.Getenv(private.GitPushOptionCount)); err == nil {
for idx := 0; idx < pushCount; idx++ {
opt := os.Getenv(fmt.Sprintf("GIT_PUSH_OPTION_%d", idx))
kv := strings.SplitN(opt, "=", 2)
if len(kv) == 2 {
opts[kv[0]] = kv[1]
}
}
}
return opts
}
func runHookProcReceive(c *cli.Context) error {
ctx, cancel := installSignals()
defer cancel()
setup(ctx, c.Bool("debug"))
if len(os.Getenv("SSH_ORIGINAL_COMMAND")) == 0 {
if setting.OnlyAllowPushIfGiteaEnvironmentSet {
return fail(ctx, `Rejecting changes as Forgejo environment not set.
If you are pushing over SSH you must push with a key managed by
Forgejo or set your environment appropriately.`, "")
}
return nil
}
if git.CheckGitVersionAtLeast("2.29") != nil {
return fail(ctx, "No proc-receive support", "current git version doesn't support proc-receive.")
}
reader := bufio.NewReader(os.Stdin)
repoUser := os.Getenv(repo_module.EnvRepoUsername)
repoName := os.Getenv(repo_module.EnvRepoName)
pusherID, _ := strconv.ParseInt(os.Getenv(repo_module.EnvPusherID), 10, 64)
pusherName := os.Getenv(repo_module.EnvPusherName)
// 1. Version and features negotiation.
// S: PKT-LINE(version=1\0push-options atomic...) / PKT-LINE(version=1\n)
// S: flush-pkt
// H: PKT-LINE(version=1\0push-options...)
// H: flush-pkt
rs, err := readPktLine(ctx, reader, pktLineTypeData)
if err != nil {
return err
}
const VersionHead string = "version=1"
var (
hasPushOptions bool
response = []byte(VersionHead)
requestOptions []string
)
index := bytes.IndexByte(rs.Data, byte(0))
if index >= len(rs.Data) {
return fail(ctx, "Protocol: format error", "pkt-line: format error "+fmt.Sprint(rs.Data))
}
if index < 0 {
if len(rs.Data) == 10 && rs.Data[9] == '\n' {
index = 9
} else {
return fail(ctx, "Protocol: format error", "pkt-line: format error "+fmt.Sprint(rs.Data))
}
}
if string(rs.Data[0:index]) != VersionHead {
return fail(ctx, "Protocol: version error", "Received unsupported version: %s", string(rs.Data[0:index]))
}
requestOptions = strings.Split(string(rs.Data[index+1:]), " ")
for _, option := range requestOptions {
if strings.HasPrefix(option, "push-options") {
response = append(response, byte(0))
response = append(response, []byte("push-options")...)
hasPushOptions = true
}
}
response = append(response, '\n')
_, err = readPktLine(ctx, reader, pktLineTypeFlush)
if err != nil {
return err
}
err = writeDataPktLine(ctx, os.Stdout, response)
if err != nil {
return err
}
err = writeFlushPktLine(ctx, os.Stdout)
if err != nil {
return err
}
// 2. receive commands from server.
// S: PKT-LINE(<old-oid> <new-oid> <ref>)
// S: ... ...
// S: flush-pkt
// # [receive push-options]
// S: PKT-LINE(push-option)
// S: ... ...
// S: flush-pkt
hookOptions := private.HookOptions{
UserName: pusherName,
UserID: pusherID,
}
hookOptions.OldCommitIDs = make([]string, 0, hookBatchSize)
hookOptions.NewCommitIDs = make([]string, 0, hookBatchSize)
hookOptions.RefFullNames = make([]git.RefName, 0, hookBatchSize)
for {
// note: pktLineTypeUnknow means pktLineTypeFlush and pktLineTypeData all allowed
rs, err = readPktLine(ctx, reader, pktLineTypeUnknown)
if err != nil {
return err
}
if rs.Type == pktLineTypeFlush {
break
}
t := strings.SplitN(string(rs.Data), " ", 3)
if len(t) != 3 {
continue
}
hookOptions.OldCommitIDs = append(hookOptions.OldCommitIDs, t[0])
hookOptions.NewCommitIDs = append(hookOptions.NewCommitIDs, t[1])
hookOptions.RefFullNames = append(hookOptions.RefFullNames, git.RefName(t[2]))
}
hookOptions.GitPushOptions = make(map[string]string)
if hasPushOptions {
for {
rs, err = readPktLine(ctx, reader, pktLineTypeUnknown)
if err != nil {
return err
}
if rs.Type == pktLineTypeFlush {
break
}
kv := strings.SplitN(string(rs.Data), "=", 2)
if len(kv) == 2 {
hookOptions.GitPushOptions[kv[0]] = kv[1]
}
}
}
// 3. run hook
resp, extra := private.HookProcReceive(ctx, repoUser, repoName, hookOptions)
if extra.HasError() {
return fail(ctx, extra.UserMsg, "HookProcReceive failed: %v", extra.Error)
}
// 4. response result to service
// # a. OK, but has an alternate reference. The alternate reference name
// # and other status can be given in option directives.
// H: PKT-LINE(ok <ref>)
// H: PKT-LINE(option refname <refname>)
// H: PKT-LINE(option old-oid <old-oid>)
// H: PKT-LINE(option new-oid <new-oid>)
// H: PKT-LINE(option forced-update)
// H: ... ...
// H: flush-pkt
// # b. NO, I reject it.
// H: PKT-LINE(ng <ref> <reason>)
// # c. Fall through, let 'receive-pack' to execute it.
// H: PKT-LINE(ok <ref>)
// H: PKT-LINE(option fall-through)
for _, rs := range resp.Results {
if len(rs.Err) > 0 {
err = writeDataPktLine(ctx, os.Stdout, []byte("ng "+rs.OriginalRef.String()+" "+rs.Err))
if err != nil {
return err
}
continue
}
if rs.IsNotMatched {
err = writeDataPktLine(ctx, os.Stdout, []byte("ok "+rs.OriginalRef.String()))
if err != nil {
return err
}
err = writeDataPktLine(ctx, os.Stdout, []byte("option fall-through"))
if err != nil {
return err
}
continue
}
err = writeDataPktLine(ctx, os.Stdout, []byte("ok "+rs.OriginalRef))
if err != nil {
return err
}
err = writeDataPktLine(ctx, os.Stdout, []byte("option refname "+rs.Ref))
if err != nil {
return err
}
commitID, _ := git.NewIDFromString(rs.OldOID)
if !commitID.IsZero() {
err = writeDataPktLine(ctx, os.Stdout, []byte("option old-oid "+rs.OldOID))
if err != nil {
return err
}
}
err = writeDataPktLine(ctx, os.Stdout, []byte("option new-oid "+rs.NewOID))
if err != nil {
return err
}
if rs.IsForcePush {
err = writeDataPktLine(ctx, os.Stdout, []byte("option forced-update"))
if err != nil {
return err
}
}
}
err = writeFlushPktLine(ctx, os.Stdout)
return err
}
// git PKT-Line api
// pktLineType message type of pkt-line
type pktLineType int64
const (
// Unknown type
pktLineTypeUnknown pktLineType = 0
// flush-pkt "0000"
pktLineTypeFlush pktLineType = iota
// data line
pktLineTypeData
)
// gitPktLine pkt-line api
type gitPktLine struct {
Type pktLineType
Length uint64
Data []byte
}
// Reads an Pkt-Line from `in`. If requestType is not unknown, it will a
func readPktLine(ctx context.Context, in *bufio.Reader, requestType pktLineType) (*gitPktLine, error) {
// Read length prefix
lengthBytes := make([]byte, 4)
if n, err := in.Read(lengthBytes); n != 4 || err != nil {
return nil, fail(ctx, "Protocol: stdin error", "Pkt-Line: read stdin failed : %v", err)
}
var err error
r := &gitPktLine{}
r.Length, err = strconv.ParseUint(string(lengthBytes), 16, 32)
if err != nil {
return nil, fail(ctx, "Protocol: format parse error", "Pkt-Line format is wrong :%v", err)
}
if r.Length == 0 {
if requestType == pktLineTypeData {
return nil, fail(ctx, "Protocol: format data error", "Pkt-Line format is wrong")
}
r.Type = pktLineTypeFlush
return r, nil
}
if r.Length <= 4 || r.Length > 65520 || requestType == pktLineTypeFlush {
return nil, fail(ctx, "Protocol: format length error", "Pkt-Line format is wrong")
}
r.Data = make([]byte, r.Length-4)
if n, err := io.ReadFull(in, r.Data); uint64(n) != r.Length-4 || err != nil {
return nil, fail(ctx, "Protocol: stdin error", "Pkt-Line: read stdin failed : %v", err)
}
r.Type = pktLineTypeData
return r, nil
}
func writeFlushPktLine(ctx context.Context, out io.Writer) error {
l, err := out.Write([]byte("0000"))
if err != nil || l != 4 {
return fail(ctx, "Protocol: write error", "Pkt-Line response failed: %v", err)
}
return nil
}
// Write an Pkt-Line based on `data` to `out` according to the specifcation.
// https://git-scm.com/docs/protocol-common
func writeDataPktLine(ctx context.Context, out io.Writer, data []byte) error {
// Implementations SHOULD NOT send an empty pkt-line ("0004").
if len(data) == 0 {
return fail(ctx, "Protocol: write error", "Not allowed to write empty Pkt-Line")
}
length := uint64(len(data) + 4)
// The maximum length of a pkt-lines data component is 65516 bytes.
// Implementations MUST NOT send pkt-line whose length exceeds 65520 (65516 bytes of payload + 4 bytes of length data).
if length > 65520 {
return fail(ctx, "Protocol: write error", "Pkt-Line exceeds maximum of 65520 bytes")
}
lr, err := fmt.Fprintf(out, "%04x", length)
if err != nil || lr != 4 {
return fail(ctx, "Protocol: write error", "Pkt-Line response failed: %v", err)
}
lr, err = out.Write(data)
if err != nil || int(length-4) != lr {
return fail(ctx, "Protocol: write error", "Pkt-Line response failed: %v", err)
}
return nil
}