Refactor git module, make Gitea use internal git config

cmd/serv.go

@@ -6,6 +6,7 @@
 package cmd
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -65,6 +66,21 @@ func setup(logPath string, debug bool) {
 	if debug {
 		setting.RunMode = "dev"
 	}
+
+	// Check if setting.RepoRootPath exists. It could be the case that it doesn't exist, this can happen when
+	// `[repository]` `ROOT` is a relative path and $GITEA_WORK_DIR isn't passed to the SSH connection.
+	if _, err := os.Stat(setting.RepoRootPath); err != nil {
+		if os.IsNotExist(err) {
+			_ = fail("Incorrect configuration, no repository directory.", "Directory `[repository].ROOT` %q was not found, please check if $GITEA_WORK_DIR is passed to the SSH connection or make `[repository].ROOT` an absolute value.", setting.RepoRootPath)
+		} else {
+			_ = fail("Incorrect configuration, repository directory is inaccessible", "Directory `[repository].ROOT` %q is inaccessible. err: %v", setting.RepoRootPath, err)
+		}
+		return
+	}
+
+	if err := git.InitSimple(context.Background()); err != nil {
+		_ = fail("Failed to init git", "Failed to init git, err: %v", err)
+	}
 }
 
 var (
@@ -80,12 +96,12 @@ var (
 func fail(userMessage, logMessage string, args ...interface{}) error {
 	// There appears to be a chance to cause a zombie process and failure to read the Exit status
 	// if nothing is outputted on stdout.
-	fmt.Fprintln(os.Stdout, "")
-	fmt.Fprintln(os.Stderr, "Gitea:", userMessage)
+	_, _ = fmt.Fprintln(os.Stdout, "")
+	_, _ = fmt.Fprintln(os.Stderr, "Gitea:", userMessage)
 
 	if len(logMessage) > 0 {
 		if !setting.IsProd {
-			fmt.Fprintf(os.Stderr, logMessage+"\n", args...)
+			_, _ = fmt.Fprintf(os.Stderr, logMessage+"\n", args...)
 		}
 	}
 	ctx, cancel := installSignals()
@@ -237,17 +253,6 @@ func runServ(c *cli.Context) error {
 		}
 		return fail("Internal Server Error", "%s", err.Error())
 	}
-	os.Setenv(repo_module.EnvRepoIsWiki, strconv.FormatBool(results.IsWiki))
-	os.Setenv(repo_module.EnvRepoName, results.RepoName)
-	os.Setenv(repo_module.EnvRepoUsername, results.OwnerName)
-	os.Setenv(repo_module.EnvPusherName, results.UserName)
-	os.Setenv(repo_module.EnvPusherEmail, results.UserEmail)
-	os.Setenv(repo_module.EnvPusherID, strconv.FormatInt(results.UserID, 10))
-	os.Setenv(repo_module.EnvRepoID, strconv.FormatInt(results.RepoID, 10))
-	os.Setenv(repo_module.EnvPRID, fmt.Sprintf("%d", 0))
-	os.Setenv(repo_module.EnvDeployKeyID, fmt.Sprintf("%d", results.DeployKeyID))
-	os.Setenv(repo_module.EnvKeyID, fmt.Sprintf("%d", results.KeyID))
-	os.Setenv(repo_module.EnvAppURL, setting.AppURL)
 
 	// LFS token authentication
 	if verb == lfsAuthenticateVerb {
@@ -298,20 +303,29 @@ func runServ(c *cli.Context) error {
 		gitcmd = exec.CommandContext(ctx, verb, repoPath)
 	}
 
-	// Check if setting.RepoRootPath exists. It could be the case that it doesn't exist, this can happen when
-	// `[repository]` `ROOT` is a relative path and $GITEA_WORK_DIR isn't passed to the SSH connection.
-	if _, err := os.Stat(setting.RepoRootPath); err != nil {
-		if os.IsNotExist(err) {
-			return fail("Incorrect configuration.",
-				"Directory `[repository]` `ROOT` %s was not found, please check if $GITEA_WORK_DIR is passed to the SSH connection or make `[repository]` `ROOT` an absolute value.", setting.RepoRootPath)
-		}
-	}
-
 	process.SetSysProcAttribute(gitcmd)
 	gitcmd.Dir = setting.RepoRootPath
 	gitcmd.Stdout = os.Stdout
 	gitcmd.Stdin = os.Stdin
 	gitcmd.Stderr = os.Stderr
+	gitcmd.Env = append(gitcmd.Env, os.Environ()...)
+	gitcmd.Env = append(gitcmd.Env,
+		repo_module.EnvRepoIsWiki+"="+strconv.FormatBool(results.IsWiki),
+		repo_module.EnvRepoName+"="+results.RepoName,
+		repo_module.EnvRepoUsername+"="+results.OwnerName,
+		repo_module.EnvPusherName+"="+results.UserName,
+		repo_module.EnvPusherEmail+"="+results.UserEmail,
+		repo_module.EnvPusherID+"="+strconv.FormatInt(results.UserID, 10),
+		repo_module.EnvRepoID+"="+strconv.FormatInt(results.RepoID, 10),
+		repo_module.EnvPRID+"="+fmt.Sprintf("%d", 0),
+		repo_module.EnvDeployKeyID+"="+fmt.Sprintf("%d", results.DeployKeyID),
+		repo_module.EnvKeyID+"="+fmt.Sprintf("%d", results.KeyID),
+		repo_module.EnvAppURL+"="+setting.AppURL,
+	)
+	// to avoid breaking, here only use the minimal environment variables for the "gitea serv" command.
+	// it could be re-considered whether to use the same git.CommonGitCmdEnvs() as "git" command later.
+	gitcmd.Env = append(gitcmd.Env, git.CommonCmdServEnvs()...)
+
 	if err = gitcmd.Run(); err != nil {
 		return fail("Internal error", "Failed to execute git command: %v", err)
 	}

integrations/integration_test.go

@@ -274,8 +274,8 @@ func prepareTestEnv(t testing.TB, skip ...int) func() {
 	deferFn := PrintCurrentTest(t, ourSkip)
 	assert.NoError(t, unittest.LoadFixtures())
 	assert.NoError(t, util.RemoveAll(setting.RepoRootPath))
-
 	assert.NoError(t, unittest.CopyDir(path.Join(filepath.Dir(setting.AppPath), "integrations/gitea-repositories-meta"), setting.RepoRootPath))
+	assert.NoError(t, git.InitWithConfigSync(context.Background()))
 	ownerDirs, err := os.ReadDir(setting.RepoRootPath)
 	if err != nil {
 		assert.NoError(t, err, "unable to read the new repo root: %v\n", err)
@@ -576,6 +576,7 @@ func resetFixtures(t *testing.T) {
 	assert.NoError(t, unittest.LoadFixtures())
 	assert.NoError(t, util.RemoveAll(setting.RepoRootPath))
 	assert.NoError(t, unittest.CopyDir(path.Join(filepath.Dir(setting.AppPath), "integrations/gitea-repositories-meta"), setting.RepoRootPath))
+	assert.NoError(t, git.InitWithConfigSync(context.Background()))
 	ownerDirs, err := os.ReadDir(setting.RepoRootPath)
 	if err != nil {
 		assert.NoError(t, err, "unable to read the new repo root: %v\n", err)

integrations/migration-test/migration_test.go

@@ -62,6 +62,7 @@ func initMigrationTest(t *testing.T) func() {
 	assert.True(t, len(setting.RepoRootPath) != 0)
 	assert.NoError(t, util.RemoveAll(setting.RepoRootPath))
 	assert.NoError(t, unittest.CopyDir(path.Join(filepath.Dir(setting.AppPath), "integrations/gitea-repositories-meta"), setting.RepoRootPath))
+	assert.NoError(t, git.InitWithConfigSync(context.Background()))
 	ownerDirs, err := os.ReadDir(setting.RepoRootPath)
 	if err != nil {
 		assert.NoError(t, err, "unable to read the new repo root: %v\n", err)

models/migrations/migrations_test.go

@@ -202,9 +202,8 @@ func prepareTestEnv(t *testing.T, skip int, syncModels ...interface{}) (*xorm.En
 	ourSkip += skip
 	deferFn := PrintCurrentTest(t, ourSkip)
 	assert.NoError(t, os.RemoveAll(setting.RepoRootPath))
-
-	assert.NoError(t, unittest.CopyDir(path.Join(filepath.Dir(setting.AppPath), "integrations/gitea-repositories-meta"),
-		setting.RepoRootPath))
+	assert.NoError(t, unittest.CopyDir(path.Join(filepath.Dir(setting.AppPath), "integrations/gitea-repositories-meta"), setting.RepoRootPath))
+	assert.NoError(t, git.InitWithConfigSync(context.Background()))
 	ownerDirs, err := os.ReadDir(setting.RepoRootPath)
 	if err != nil {
 		assert.NoError(t, err, "unable to read the new repo root: %v\n", err)

models/unittest/testdb.go

@@ -14,6 +14,7 @@ import (
 
 	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/storage"
 	"code.gitea.io/gitea/modules/util"
@@ -116,6 +117,9 @@ func MainTest(m *testing.M, testOpts *TestOptions) {
 	if err = CopyDir(filepath.Join(testOpts.GiteaRootPath, "integrations", "gitea-repositories-meta"), setting.RepoRootPath); err != nil {
 		fatalTestError("util.CopyDir: %v\n", err)
 	}
+	if err = git.InitWithConfigSync(context.Background()); err != nil {
+		fatalTestError("git.Init: %v\n", err)
+	}
 
 	ownerDirs, err := os.ReadDir(setting.RepoRootPath)
 	if err != nil {
@@ -198,6 +202,7 @@ func PrepareTestEnv(t testing.TB) {
 	assert.NoError(t, util.RemoveAll(setting.RepoRootPath))
 	metaPath := filepath.Join(giteaRoot, "integrations", "gitea-repositories-meta")
 	assert.NoError(t, CopyDir(metaPath, setting.RepoRootPath))
+	assert.NoError(t, git.InitWithConfigSync(context.Background()))
 
 	ownerDirs, err := os.ReadDir(setting.RepoRootPath)
 	assert.NoError(t, err)

modules/git/command.go

@@ -8,10 +8,12 @@ package git
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
 	"time"
 	"unsafe"
@@ -104,6 +106,25 @@ type RunOpts struct {
 	PipelineFunc   func(context.Context, context.CancelFunc) error
 }
 
+// CommonGitCmdEnvs returns the common environment variables for a "git" command.
+func CommonGitCmdEnvs() []string {
+	// at the moment, do not set "GIT_CONFIG_NOSYSTEM", users may have put some configs like "receive.certNonceSeed" in it
+	return []string{
+		fmt.Sprintf("LC_ALL=%s", DefaultLocale),
+		"GIT_TERMINAL_PROMPT=0",    // avoid prompting for credentials interactively, supported since git v2.3
+		"GIT_NO_REPLACE_OBJECTS=1", // ignore replace references (https://git-scm.com/docs/git-replace)
+		"HOME=" + HomeDir,          // make Gitea use internal git config only, to prevent conflicts with user's git config
+	}
+}
+
+// CommonCmdServEnvs is like CommonGitCmdEnvs but it only returns minimal required environment variables for the "gitea serv" command
+func CommonCmdServEnvs() []string {
+	return []string{
+		"GIT_NO_REPLACE_OBJECTS=1", // ignore replace references (https://git-scm.com/docs/git-replace)
+		"HOME=" + HomeDir,          // make Gitea use internal git config only, to prevent conflicts with user's git config
+	}
+}
+
 // Run runs the command with the RunOpts
 func (c *Command) Run(opts *RunOpts) error {
 	if opts == nil {
@@ -148,16 +169,16 @@ func (c *Command) Run(opts *RunOpts) error {
 		cmd.Env = opts.Env
 	}
 
-	cmd.Env = append(
-		cmd.Env,
-		fmt.Sprintf("LC_ALL=%s", DefaultLocale),
-		// avoid prompting for credentials interactively, supported since git v2.3
-		"GIT_TERMINAL_PROMPT=0",
-		// ignore replace references (https://git-scm.com/docs/git-replace)
-		"GIT_NO_REPLACE_OBJECTS=1",
-	)
+	if HomeDir == "" {
+		// TODO: now, some unit test code call the git module directly without initialization, which is incorrect.
+		// at the moment, we just use a temp HomeDir to prevent from conflicting with user's git config
+		// in future, the git module should be initialized first before use.
+		HomeDir = filepath.Join(os.TempDir(), "/gitea-temp-home")
+		log.Warn("Git's HomeDir is empty, the git module is not initialized correctly, using a temp HomeDir (%s) temporarily", HomeDir)
+	}
 
 	process.SetSysProcAttribute(cmd)
+	cmd.Env = append(cmd.Env, CommonGitCmdEnvs()...)
 	cmd.Dir = opts.Dir
 	cmd.Stdout = opts.Stdout
 	cmd.Stderr = opts.Stderr
@@ -184,7 +205,9 @@ func (c *Command) Run(opts *RunOpts) error {
 
 type RunStdError interface {
 	error
+	Unwrap() error
 	Stderr() string
+	IsExitCode(code int) bool
 }
 
 type runStdError struct {
@@ -209,6 +232,14 @@ func (r *runStdError) Stderr() string {
 	return r.stderr
 }
 
+func (r *runStdError) IsExitCode(code int) bool {
+	var exitError *exec.ExitError
+	if errors.As(r.err, &exitError) {
+		return exitError.ExitCode() == code
+	}
+	return false
+}
+
 func bytesToString(b []byte) string {
 	return *(*string)(unsafe.Pointer(&b)) // that's what Golang's strings.Builder.String() does (go/src/strings/builder.go)
 }

modules/git/commit.go

@@ -398,11 +398,6 @@ func (c *Commit) GetSubModule(entryname string) (*SubModule, error) {
 
 // GetBranchName gets the closest branch name (as returned by 'git name-rev --name-only')
 func (c *Commit) GetBranchName() (string, error) {
-	err := LoadGitVersion()
-	if err != nil {
-		return "", fmt.Errorf("Git version missing: %v", err)
-	}
-
 	args := []string{
 		"name-rev",
 	}