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gitea/cmd/hook.go
wxiaoguang 6f9c278559
Rewrite queue (#24505)
# ⚠️ Breaking

Many deprecated queue config options are removed (actually, they should
have been removed in 1.18/1.19).

If you see the fatal message when starting Gitea: "Please update your
app.ini to remove deprecated config options", please follow the error
messages to remove these options from your app.ini.

Example:

```
2023/05/06 19:39:22 [E] Removed queue option: `[indexer].ISSUE_INDEXER_QUEUE_TYPE`. Use new options in `[queue.issue_indexer]`
2023/05/06 19:39:22 [E] Removed queue option: `[indexer].UPDATE_BUFFER_LEN`. Use new options in `[queue.issue_indexer]`
2023/05/06 19:39:22 [F] Please update your app.ini to remove deprecated config options
```

Many options in `[queue]` are are dropped, including:
`WRAP_IF_NECESSARY`, `MAX_ATTEMPTS`, `TIMEOUT`, `WORKERS`,
`BLOCK_TIMEOUT`, `BOOST_TIMEOUT`, `BOOST_WORKERS`, they can be removed
from app.ini.

# The problem

The old queue package has some legacy problems:

* complexity: I doubt few people could tell how it works.
* maintainability: Too many channels and mutex/cond are mixed together,
too many different structs/interfaces depends each other.
* stability: due to the complexity & maintainability, sometimes there
are strange bugs and difficult to debug, and some code doesn't have test
(indeed some code is difficult to test because a lot of things are mixed
together).
* general applicability: although it is called "queue", its behavior is
not a well-known queue.
* scalability: it doesn't seem easy to make it work with a cluster
without breaking its behaviors.

It came from some very old code to "avoid breaking", however, its
technical debt is too heavy now. It's a good time to introduce a better
"queue" package.

# The new queue package

It keeps using old config and concept as much as possible.

* It only contains two major kinds of concepts:
    * The "base queue": channel, levelqueue, redis
* They have the same abstraction, the same interface, and they are
tested by the same testing code.
* The "WokerPoolQueue", it uses the "base queue" to provide "worker
pool" function, calls the "handler" to process the data in the base
queue.
* The new code doesn't do "PushBack"
* Think about a queue with many workers, the "PushBack" can't guarantee
the order for re-queued unhandled items, so in new code it just does
"normal push"
* The new code doesn't do "pause/resume"
* The "pause/resume" was designed to handle some handler's failure: eg:
document indexer (elasticsearch) is down
* If a queue is paused for long time, either the producers blocks or the
new items are dropped.
* The new code doesn't do such "pause/resume" trick, it's not a common
queue's behavior and it doesn't help much.
* If there are unhandled items, the "push" function just blocks for a
few seconds and then re-queue them and retry.
* The new code doesn't do "worker booster"
* Gitea's queue's handlers are light functions, the cost is only the
go-routine, so it doesn't make sense to "boost" them.
* The new code only use "max worker number" to limit the concurrent
workers.
* The new "Push" never blocks forever
* Instead of creating more and more blocking goroutines, return an error
is more friendly to the server and to the end user.

There are more details in code comments: eg: the "Flush" problem, the
strange "code.index" hanging problem, the "immediate" queue problem.

Almost ready for review.

TODO:

* [x] add some necessary comments during review
* [x] add some more tests if necessary
* [x] update documents and config options
* [x] test max worker / active worker
* [x] re-run the CI tasks to see whether any test is flaky
* [x] improve the `handleOldLengthConfiguration` to provide more
friendly messages
* [x] fine tune default config values (eg: length?)

## Code coverage:

![image](https://user-images.githubusercontent.com/2114189/236620635-55576955-f95d-4810-b12f-879026a3afdf.png)
2023-05-08 19:49:59 +08:00

790 lines
20 KiB
Go

// 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/private"
repo_module "code.gitea.io/gitea/modules/repository"
"code.gitea.io/gitea/modules/setting"
"github.com/urfave/cli"
)
const (
hookBatchSize = 30
)
var (
// CmdHook represents the available hooks sub-command.
CmdHook = cli.Command{
Name: "hook",
Usage: "Delegate commands to corresponding Git hooks",
Description: "This should only be called by Git",
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 Gitea environment not set.
If you are pushing over SSH you must push with a key managed by
Gitea 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([]string, 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 := string(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 || strings.HasPrefix(refFullName, git.BranchPrefix) || strings.HasPrefix(refFullName, git.TagPrefix) {
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
}
func runHookUpdate(c *cli.Context) error {
// Update is empty and is kept only for backwards compatibility
return nil
}
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 Gitea environment not set.
If you are pushing over SSH you must push with a key managed by
Gitea or set your environment appropriately.`, "")
}
return nil
}
var out io.Writer
var dWriter *delayWriter
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([]string, 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] = string(fields[2])
if refFullNames[count] == git.BranchPrefix+"master" && newCommitIDs[count] != git.EmptySHA && 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() {
_ = dWriter.Close()
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)
_ = dWriter.Close()
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 {
_ = dWriter.Close()
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)
}
}
_ = dWriter.Close()
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 Gitea environment not set.
If you are pushing over SSH you must push with a key managed by
Gitea 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([]string, 0, hookBatchSize)
for {
// note: pktLineTypeUnknow means pktLineTypeFlush and pktLineTypeData all allowed
rs, err = readPktLine(ctx, reader, pktLineTypeUnknow)
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, t[2])
}
hookOptions.GitPushOptions = make(map[string]string)
if hasPushOptions {
for {
rs, err = readPktLine(ctx, reader, pktLineTypeUnknow)
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+" "+rs.Err))
if err != nil {
return err
}
continue
}
if rs.IsNotMatched {
err = writeDataPktLine(ctx, os.Stdout, []byte("ok "+rs.OriginalRef))
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
}
if rs.OldOID != git.EmptySHA {
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 (
// UnKnow type
pktLineTypeUnknow pktLineType = 0
// flush-pkt "0000"
pktLineTypeFlush pktLineType = iota
// data line
pktLineTypeData
)
// gitPktLine pkt-line api
type gitPktLine struct {
Type pktLineType
Length uint64
Data []byte
}
func readPktLine(ctx context.Context, in *bufio.Reader, requestType pktLineType) (*gitPktLine, error) {
var (
err error
r *gitPktLine
)
// read prefix
lengthBytes := make([]byte, 4)
for i := 0; i < 4; i++ {
lengthBytes[i], err = in.ReadByte()
if err != nil {
return nil, fail(ctx, "Protocol: stdin error", "Pkt-Line: read stdin failed : %v", err)
}
}
r = new(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)
for i := range r.Data {
r.Data[i], err = in.ReadByte()
if err != nil {
return nil, fail(ctx, "Protocol: data 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
}
func writeDataPktLine(ctx context.Context, out io.Writer, data []byte) error {
hexchar := []byte("0123456789abcdef")
hex := func(n uint64) byte {
return hexchar[(n)&15]
}
length := uint64(len(data) + 4)
tmp := make([]byte, 4)
tmp[0] = hex(length >> 12)
tmp[1] = hex(length >> 8)
tmp[2] = hex(length >> 4)
tmp[3] = hex(length)
lr, err := out.Write(tmp)
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
}