reduce goroot file copy

README.md

@@ -8,7 +8,7 @@
 
 **English | [简体中文](./README_zh_cn.md)**
 
-Enable function Trap for `go`, and provide tools like Mock and Trace to help go developers write unit test and debug both easier and faster.
+Enable function Trap in `go`, provide tools like Mock and Trace to help go developers write unit test and debug both easier and faster.
 
 `xgo` works as a preprocessor for `go run`,`go build`, and `go test`(see our [blog](https://blog.xhd2015.xyz/posts/xgo-monkey-patching-in-go-using-toolexec/)).
 
@@ -41,18 +41,12 @@ There are other options,see [doc/INSTALLATION.md](./doc/INSTALLATION.md).
 There is no specific limitation on OS and Architecture. 
 
 **All OS and Architectures** are supported by `xgo` as long as they are supported by `go`.
-
-OS:
-- MacOS
-- Linux
-- Windows (+WSL)
-- ...
-
-Architecture:
-- x86
-- x86_64(amd64)
-- arm64
-- ...
+|         | x86_64    | ARM64     | Any Other Arch...     |
+|---------|-----------|-----------|-----------|
+| Linux   | Y | Y | Y|
+| Windows | Y | Y | Y|
+| macOS   | Y | Y | Y|
+| Any Other OS...   | Y | Y | Y|
 
 # Quick Start
 Let's write a unit test with `xgo`:

README_zh_cn.md

@@ -9,7 +9,7 @@
 
 允许对`go`的函数进行拦截, 并提供Mock和Trace等工具帮助开发者编写测试和快速调试。
 
-`xgo`作为一个预处理器工作在`go run`,`go build`,和`go test`之上(查看[blog](https://blog.xhd2015.xyz/posts/xgo-monkey-patching-in-go-using-toolexec/))。
+`xgo`作为一个预处理器工作在`go run`,`go build`,和`go test`之上(查看[blog](https://blog.xhd2015.xyz/zh/posts/xgo-monkey-patching-in-go-using-toolexec/))。
 
 `xgo`对源代码和IR(中间码)进行预处理之后, 再调用`go`进行后续的编译工作。通过这种方式, `xgo`实现了一些在`go`中缺乏的能力。
 
@@ -39,17 +39,12 @@ xgo version
 
 对OS和Arch没有限制, `xgo`支持所有`go`支持的OS和Arch。
 
-OS:
-- macOS
-- Linux
-- Windows (+WSL)
-- ...
-
-Arch:
-- x86
-- x86_64(amd64)
-- arm64
-- ...
+|         | x86_64    | ARM64     | 任何其他架构...     |
+|---------|-----------|-----------|-----------|
+| Linux   | Y | Y | Y|
+| Windows | Y | Y | Y|
+| macOS   | Y | Y | Y|
+| 任何其他OS...   | Y | Y | Y|
 
 # 快速开始
 我们基于`xgo`编写一个单元测试:

cmd/xgo/main.go

@@ -241,6 +241,7 @@ func handleBuild(cmd string, args []string) error {
 	}
 	buildCacheDir := filepath.Join(instrumentDir, "build-cache"+buildCacheSuffix)
 	revisionFile := filepath.Join(instrumentDir, "xgo-revision.txt")
+	fullSyncRecord := filepath.Join(instrumentDir, "full-sync-record.txt")
 
 	var realXgoSrc string
 	if isDevelopment {
@@ -294,7 +295,7 @@ func handleBuild(cmd string, args []string) error {
 		}
 		if isDevelopment || resetInstrument || revisionChanged {
 			logDebug("sync goroot %s -> %s", goroot, instrumentGoroot)
-			err = syncGoroot(goroot, instrumentGoroot, revisionChanged)
+			err = syncGoroot(goroot, instrumentGoroot, fullSyncRecord)
 			if err != nil {
 				return err
 			}

cmd/xgo/patch.go

@@ -9,12 +9,34 @@ import (
 	"os/exec"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/xhd2015/xgo/support/filecopy"
 	"github.com/xhd2015/xgo/support/goinfo"
 	"github.com/xhd2015/xgo/support/osinfo"
 )
 
+// the _FilePath declared at toplevel
+// serves as an item list where
+// the runtime and compiler maybe
+// affected.
+// NOTE: do not remove files, always add files,
+// these old files may exists in older version
+// so can be cleared by newer xgo
+type _FilePath []string
+
+func (c _FilePath) Join(s ...string) string {
+	return filepath.Join(filepath.Join(s...), filepath.Join(c...))
+}
+
+var affectedFiles []_FilePath
+
+func init() {
+	affectedFiles = append(affectedFiles, compilerFiles...)
+	affectedFiles = append(affectedFiles, runtimeFiles...)
+	affectedFiles = append(affectedFiles, reflectFiles...)
+}
+
 // assume go 1.20
 // the patch should be idempotent
 // the origGoroot is used to generate runtime defs, see https://github.com/xhd2015/xgo/issues/4#issuecomment-2017880791
@@ -44,14 +66,6 @@ func patchRuntimeAndCompiler(origGoroot string, goroot string, xgoSrc string, go
 	return nil
 }
 
-func getInternalPatch(goroot string, subDirs ...string) string {
-	dir := filepath.Join(goroot, "src", "cmd", "compile", "internal", "xgo_rewrite_internal", "patch")
-	if len(subDirs) > 0 {
-		dir = filepath.Join(dir, filepath.Join(subDirs...))
-	}
-	return dir
-}
-
 func replaceBuildIgnore(content []byte) ([]byte, error) {
 	const buildIgnore = "//go:build ignore"
 
@@ -101,50 +115,104 @@ func readOrEmpty(file string) (string, error) {
 }
 
 // NOTE: flagA never cause goroot to reset
-func syncGoroot(goroot string, dstDir string, forceCopy bool) error {
+func syncGoroot(goroot string, instrumentGoroot string, fullSyncRecordFile string) error {
 	// check if src goroot has src/runtime
 	srcRuntimeDir := filepath.Join(goroot, "src", "runtime")
 	err := assertDir(srcRuntimeDir)
 	if err != nil {
 		return err
 	}
-	if !forceCopy {
-		srcGoBin := filepath.Join(goroot, "bin", "go")
-		dstGoBin := filepath.Join(dstDir, "bin", "go")
+	var goBinaryChanged bool = true
+	srcGoBin := filepath.Join(goroot, "bin", "go")
+	dstGoBin := filepath.Join(instrumentGoroot, "bin", "go")
+
+	srcFile, err := os.Stat(srcGoBin)
+	if err != nil {
+		return nil
+	}
+	if srcFile.IsDir() {
+		return fmt.Errorf("bad goroot: %s", goroot)
+	}
+
+	dstFile, statErr := os.Stat(dstGoBin)
+	if statErr != nil {
+		if !os.IsNotExist(statErr) {
+			return statErr
+		}
+	}
 
-		srcFile, err := os.Stat(srcGoBin)
+	if dstFile != nil && !dstFile.IsDir() && dstFile.Size() == srcFile.Size() {
+		goBinaryChanged = false
+	}
+
+	var doPartialCopy bool
+	if !goBinaryChanged && statNoErr(fullSyncRecordFile) {
+		// full sync record does not yet exist
+		doPartialCopy = true
+	}
+	if doPartialCopy {
+		// do partial copy
+		err := partialCopy(goroot, instrumentGoroot)
 		if err != nil {
-			return nil
+			return err
 		}
-		if srcFile.IsDir() {
-			return fmt.Errorf("bad goroot: %s", goroot)
+	} else {
+		rmErr := os.Remove(fullSyncRecordFile)
+		if rmErr != nil {
+			if !errors.Is(rmErr, os.ErrNotExist) {
+				return rmErr
+			}
 		}
 
-		dstFile, statErr := os.Stat(dstGoBin)
-		if statErr != nil {
-			if !os.IsNotExist(statErr) {
-				return statErr
-			}
+		// need copy, delete target dst dir first
+		// TODO: use git worktree add if .git exists
+		err = filecopy.NewOptions().
+			Concurrent(10).
+			CopyReplaceDir(goroot, instrumentGoroot)
+		if err != nil {
+			return err
 		}
 
-		if dstFile != nil && !dstFile.IsDir() && dstFile.Size() == srcFile.Size() {
-			// already copied
-			return nil
+		// record this full sync
+		copyTime := time.Now().Format("2006-01-02T15:04:05Z07:00")
+		err = os.WriteFile(fullSyncRecordFile, []byte(copyTime), 0755)
+		if err != nil {
+			return err
 		}
 	}
+	// change binary executable
+	return nil
+}
 
-	// need copy, delete target dst dir first
-	// TODO: use git worktree add if .git exists
-	err = filecopy.NewOptions().
-		Concurrent(10).
-		CopyReplaceDir(goroot, dstDir)
+func partialCopy(goroot string, instrumentGoroot string) error {
+	err := os.RemoveAll(xgoRewriteInternal.Join(instrumentGoroot))
 	if err != nil {
 		return err
 	}
-	// change binary executable
+	for _, affectedFile := range affectedFiles {
+		srcFile := affectedFile.Join(goroot)
+		dstFile := affectedFile.Join(instrumentGoroot)
+
+		err := filecopy.CopyFileAll(srcFile, dstFile)
+		if err != nil {
+			if !errors.Is(err, os.ErrNotExist) {
+				return err
+			}
+			// delete dstFile
+			err := os.RemoveAll(dstFile)
+			if err != nil {
+				return err
+			}
+			continue
+		}
+	}
 	return nil
 }
 
+func statNoErr(f string) bool {
+	_, err := os.Stat(f)
+	return err == nil
+}
 func buildInstrumentTool(goroot string, xgoSrc string, compilerBin string, compilerBuildIDFile string, execToolBin string, xgoBin string, debugPkg string, logCompile bool, noSetup bool, debugWithDlv bool) (compilerChanged bool, toolExecFlag string, err error) {
 	var execToolCmd []string
 	if !noSetup {