rename cache global to sharedCache

Since we will start importing github.com/rogpeppe/go-internal/cache,
and I don't want to have to rename it or leave confusion around.

hash.go

@@ -93,15 +93,15 @@ func addGarbleToHash(inputHash []byte) []byte {
 	// content ID.
 	hasher.Reset()
 	hasher.Write(inputHash)
-	if len(cache.BinaryContentID) == 0 {
+	if len(sharedCache.BinaryContentID) == 0 {
 		panic("missing binary content ID")
 	}
-	hasher.Write(cache.BinaryContentID)
+	hasher.Write(sharedCache.BinaryContentID)
 
 	// We also need to add the selected options to the full version string,
 	// because all of them result in different output. We use spaces to
 	// separate the env vars and flags, to reduce the chances of collisions.
-	fmt.Fprintf(hasher, " GOGARBLE=%s", cache.GOGARBLE)
+	fmt.Fprintf(hasher, " GOGARBLE=%s", sharedCache.GOGARBLE)
 	appendFlags(hasher, true)
 	// addGarbleToHash returns the sum buffer, so we need a new copy.
 	// Otherwise the next use of the global sumBuffer would conflict.
@@ -198,7 +198,7 @@ func toUpper(b byte) byte { return b - ('a' - 'A') }
 func runtimeHashWithCustomSalt(salt []byte) uint32 {
 	hasher.Reset()
 	if !flagSeed.present() {
-		hasher.Write(cache.ListedPackages["runtime"].GarbleActionID)
+		hasher.Write(sharedCache.ListedPackages["runtime"].GarbleActionID)
 	} else {
 		hasher.Write(flagSeed.bytes)
 	}

main.go

@@ -270,7 +270,7 @@ func goVersionOK() bool {
 	// rxVersion looks for a version like "go1.2" or "go1.2.3"
 	rxVersion := regexp.MustCompile(`go\d+\.\d+(?:\.\d+)?`)
 
-	toolchainVersionFull := cache.GoEnv.GOVERSION
+	toolchainVersionFull := sharedCache.GoEnv.GOVERSION
 	toolchainVersion := rxVersion.FindString(toolchainVersionFull)
 	if toolchainVersion == "" {
 		// Go 1.15.x and older do not have GOVERSION yet.
@@ -280,8 +280,8 @@ func goVersionOK() bool {
 		return false
 	}
 
-	cache.GoVersionSemver = "v" + strings.TrimPrefix(toolchainVersion, "go")
-	if semver.Compare(cache.GoVersionSemver, minGoVersionSemver) < 0 {
+	sharedCache.GoVersionSemver = "v" + strings.TrimPrefix(toolchainVersion, "go")
+	if semver.Compare(sharedCache.GoVersionSemver, minGoVersionSemver) < 0 {
 		fmt.Fprintf(os.Stderr, "Go version %q is too old; please upgrade to Go %s or newer\n", toolchainVersionFull, suggestedGoVersion)
 		return false
 	}
@@ -299,7 +299,7 @@ func goVersionOK() bool {
 		return true
 	}
 	builtVersionSemver := "v" + strings.TrimPrefix(builtVersion, "go")
-	if semver.Compare(builtVersionSemver, cache.GoVersionSemver) < 0 {
+	if semver.Compare(builtVersionSemver, sharedCache.GoVersionSemver) < 0 {
 		fmt.Fprintf(os.Stderr, `
 garble was built with %q and is being used with %q; rebuild it with a command like:
     garble install mvdan.cc/garble@latest
@@ -428,7 +428,7 @@ func mainErr(args []string) error {
 			}
 
 			toolexecImportPath := os.Getenv("TOOLEXEC_IMPORTPATH")
-			curPkg = cache.ListedPackages[toolexecImportPath]
+			curPkg = sharedCache.ListedPackages[toolexecImportPath]
 			if curPkg == nil {
 				return fmt.Errorf("TOOLEXEC_IMPORTPATH not found in listed packages: %s", toolexecImportPath)
 			}
@@ -444,7 +444,7 @@ func mainErr(args []string) error {
 
 		executablePath := args[0]
 		if tool == "link" {
-			modifiedLinkPath, unlock, err := linker.PatchLinker(cache.GoEnv.GOROOT, cache.GoEnv.GOVERSION, sharedTempDir)
+			modifiedLinkPath, unlock, err := linker.PatchLinker(sharedCache.GoEnv.GOROOT, sharedCache.GoEnv.GOVERSION, sharedTempDir)
 			if err != nil {
 				return fmt.Errorf("cannot get modified linker: %v", err)
 			}
@@ -509,13 +509,13 @@ This command wraps "go %s". Below is its help:
 
 	// Here is the only place we initialize the cache.
 	// The sub-processes will parse it from a shared gob file.
-	cache = &sharedCache{}
+	sharedCache = &sharedCacheType{}
 
 	// Note that we also need to pass build flags to 'go list', such
 	// as -tags.
-	cache.ForwardBuildFlags, _ = filterForwardBuildFlags(flags)
+	sharedCache.ForwardBuildFlags, _ = filterForwardBuildFlags(flags)
 	if command == "test" {
-		cache.ForwardBuildFlags = append(cache.ForwardBuildFlags, "-test")
+		sharedCache.ForwardBuildFlags = append(sharedCache.ForwardBuildFlags, "-test")
 	}
 
 	if err := fetchGoEnv(); err != nil {
@@ -527,16 +527,16 @@ This command wraps "go %s". Below is its help:
 	}
 
 	var err error
-	cache.ExecPath, err = os.Executable()
+	sharedCache.ExecPath, err = os.Executable()
 	if err != nil {
 		return nil, err
 	}
 
-	binaryBuildID, err := buildidOf(cache.ExecPath)
+	binaryBuildID, err := buildidOf(sharedCache.ExecPath)
 	if err != nil {
 		return nil, err
 	}
-	cache.BinaryContentID = decodeHash(splitContentID(binaryBuildID))
+	sharedCache.BinaryContentID = decodeHash(splitContentID(binaryBuildID))
 
 	if err := appendListedPackages(args, true); err != nil {
 		return nil, err
@@ -578,7 +578,7 @@ This command wraps "go %s". Below is its help:
 	// We can add extra flags to the end of the same -toolexec argument.
 	var toolexecFlag strings.Builder
 	toolexecFlag.WriteString("-toolexec=")
-	quotedExecPath, err := cmdgoQuotedJoin([]string{cache.ExecPath})
+	quotedExecPath, err := cmdgoQuotedJoin([]string{sharedCache.ExecPath})
 	if err != nil {
 		// Can only happen if the absolute path to the garble binary contains
 		// both single and double quotes. Seems extremely unlikely.
@@ -1394,7 +1394,7 @@ func (tf *transformer) prefillObjectMaps(files []*ast.File) error {
 	// If we do confirm this theoretical bug,
 	// the solution will be to either find a different solution for -literals,
 	// or to force including -ldflags into the build cache key.
-	ldflags, err := cmdgoQuotedSplit(flagValue(cache.ForwardBuildFlags, "-ldflags"))
+	ldflags, err := cmdgoQuotedSplit(flagValue(sharedCache.ForwardBuildFlags, "-ldflags"))
 	if err != nil {
 		return err
 	}
@@ -1953,7 +1953,7 @@ func transformLink(args []string) ([]string, error) {
 		// Otherwise, find it in the cache.
 		lpkg := curPkg
 		if path != "main" {
-			lpkg = cache.ListedPackages[path]
+			lpkg = sharedCache.ListedPackages[path]
 		}
 		if lpkg == nil {
 			// We couldn't find the package.
@@ -2191,12 +2191,12 @@ To install Go, see: https://go.dev/doc/install
 `, err)
 		return errJustExit(1)
 	}
-	if err := json.Unmarshal(out, &cache.GoEnv); err != nil {
+	if err := json.Unmarshal(out, &sharedCache.GoEnv); err != nil {
 		return fmt.Errorf(`cannot unmarshal from "go env -json": %w`, err)
 	}
-	cache.GOGARBLE = os.Getenv("GOGARBLE")
-	if cache.GOGARBLE == "" {
-		cache.GOGARBLE = "*" // we default to obfuscating everything
+	sharedCache.GOGARBLE = os.Getenv("GOGARBLE")
+	if sharedCache.GOGARBLE == "" {
+		sharedCache.GOGARBLE = "*" // we default to obfuscating everything
 	}
 	return nil
 }

reverse.go

@@ -66,7 +66,7 @@ One can reverse a captured panic stack trace as follows:
 	// so it's unnecessary to try to avoid this cost.
 	var replaces []string
 
-	for _, lpkg := range cache.ListedPackages {
+	for _, lpkg := range sharedCache.ListedPackages {
 		if !lpkg.ToObfuscate {
 			continue
 		}

runtime_patch.go

@@ -238,7 +238,7 @@ func stripRuntime(basename string, file *ast.File) {
 				"printAncestorTracebackFuncInfo", "goroutineheader", "tracebackothers", "tracebackHexdump", "printCgoTraceback":
 				funcDecl.Body.List = nil
 			case "printOneCgoTraceback":
-				if semver.Compare(cache.GoVersionSemver, "v1.21") >= 0 {
+				if semver.Compare(sharedCache.GoVersionSemver, "v1.21") >= 0 {
 					funcDecl.Body = ah.BlockStmt(ah.ReturnStmt(ast.NewIdent("false")))
 				} else {
 					funcDecl.Body = ah.BlockStmt(ah.ReturnStmt(ah.IntLit(0)))

shared.go

@@ -21,13 +21,13 @@ import (
 
 //go:generate ./scripts/gen-go-std-tables.sh
 
-// sharedCache is shared as a read-only cache between the many garble toolexec
+// sharedCacheType is shared as a read-only cache between the many garble toolexec
 // sub-processes.
 //
 // Note that we fill this cache once from the root process in saveListedPackages,
 // store it into a temporary file via gob encoding, and then reuse that file
 // in each of the garble toolexec sub-processes.
-type sharedCache struct {
+type sharedCacheType struct {
 	ExecPath          string   // absolute path to the garble binary being used
 	ForwardBuildFlags []string // build flags fed to the original "garble ..." command
 
@@ -64,11 +64,11 @@ type sharedCache struct {
 	}
 }
 
-var cache *sharedCache
+var sharedCache *sharedCacheType
 
 // loadSharedCache the shared data passed from the entry garble process
 func loadSharedCache() error {
-	if cache != nil {
+	if sharedCache != nil {
 		panic("shared cache loaded twice?")
 	}
 	startTime := time.Now()
@@ -80,7 +80,7 @@ func loadSharedCache() error {
 		log.Printf("shared cache loaded in %s from %s", debugSince(startTime), f.Name())
 	}()
 	defer f.Close()
-	if err := gob.NewDecoder(f).Decode(&cache); err != nil {
+	if err := gob.NewDecoder(f).Decode(&sharedCache); err != nil {
 		return fmt.Errorf("cannot decode shared file: %v", err)
 	}
 	return nil
@@ -89,7 +89,7 @@ func loadSharedCache() error {
 // saveSharedCache creates a temporary directory to share between garble processes.
 // This directory also includes the gob-encoded cache global.
 func saveSharedCache() (string, error) {
-	if cache == nil {
+	if sharedCache == nil {
 		panic("saving a missing cache?")
 	}
 	dir, err := os.MkdirTemp("", "garble-shared")
@@ -97,8 +97,8 @@ func saveSharedCache() (string, error) {
 		return "", err
 	}
 
-	sharedCache := filepath.Join(dir, "main-cache.gob")
-	if err := writeGobExclusive(sharedCache, &cache); err != nil {
+	cachePath := filepath.Join(dir, "main-cache.gob")
+	if err := writeGobExclusive(cachePath, &sharedCache); err != nil {
 		return "", err
 	}
 	return dir, nil
@@ -220,7 +220,7 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 		args = append(args, "-deps")
 	}
 	args = append(args, garbleBuildFlags...)
-	args = append(args, cache.ForwardBuildFlags...)
+	args = append(args, sharedCache.ForwardBuildFlags...)
 
 	if !mainBuild {
 		// If the top-level build included the -mod or -modfile flags,
@@ -251,8 +251,8 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 	}
 
 	dec := json.NewDecoder(stdout)
-	if cache.ListedPackages == nil {
-		cache.ListedPackages = make(map[string]*listedPackage)
+	if sharedCache.ListedPackages == nil {
+		sharedCache.ListedPackages = make(map[string]*listedPackage)
 	}
 	var pkgErrors []string
 	for dec.More() {
@@ -315,7 +315,7 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 		// because some like crypto/internal/boring/fipstls simply fall under
 		// "build constraints exclude all Go files" and can be ignored.
 		// Real build errors will still be surfaced by `go build -toolexec` later.
-		if cache.ListedPackages[pkg.ImportPath] != nil {
+		if sharedCache.ListedPackages[pkg.ImportPath] != nil {
 			return fmt.Errorf("duplicate package: %q", pkg.ImportPath)
 		}
 		if pkg.BuildID != "" {
@@ -323,7 +323,7 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 			pkg.GarbleActionID = addGarbleToHash(actionID)
 		}
 
-		cache.ListedPackages[pkg.ImportPath] = &pkg
+		sharedCache.ListedPackages[pkg.ImportPath] = &pkg
 	}
 
 	if err := cmd.Wait(); err != nil {
@@ -334,7 +334,7 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 	}
 
 	anyToObfuscate := false
-	for path, pkg := range cache.ListedPackages {
+	for path, pkg := range sharedCache.ListedPackages {
 		// If "GOGARBLE=foo/bar", "foo/bar_test" should also match.
 		if pkg.ForTest != "" {
 			path = pkg.ForTest
@@ -357,7 +357,7 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 		case pkg.Name == "main" && strings.HasSuffix(path, ".test"),
 			path == "command-line-arguments",
 			strings.HasPrefix(path, "plugin/unnamed"),
-			module.MatchPrefixPatterns(cache.GOGARBLE, path):
+			module.MatchPrefixPatterns(sharedCache.GOGARBLE, path):
 
 			pkg.ToObfuscate = true
 			anyToObfuscate = true
@@ -368,8 +368,8 @@ func appendListedPackages(packages []string, mainBuild bool) error {
 	}
 
 	// Don't error if the user ran: GOGARBLE='*' garble build runtime
-	if !anyToObfuscate && !module.MatchPrefixPatterns(cache.GOGARBLE, "runtime") {
-		return fmt.Errorf("GOGARBLE=%q does not match any packages to be built", cache.GOGARBLE)
+	if !anyToObfuscate && !module.MatchPrefixPatterns(sharedCache.GOGARBLE, "runtime") {
+		return fmt.Errorf("GOGARBLE=%q does not match any packages to be built", sharedCache.GOGARBLE)
 	}
 
 	return nil
@@ -394,7 +394,7 @@ func listPackage(path string) (*listedPackage, error) {
 		path = path2
 	}
 
-	pkg, ok := cache.ListedPackages[path]
+	pkg, ok := sharedCache.ListedPackages[path]
 
 	// The runtime may list any package in std, even those it doesn't depend on.
 	// This is due to how it linkname-implements std packages,
@@ -412,11 +412,11 @@ func listPackage(path string) (*listedPackage, error) {
 		missing := make([]string, 0, len(runtimeLinknamed))
 		for _, linknamed := range runtimeLinknamed {
 			switch {
-			case cache.ListedPackages[linknamed] != nil:
+			case sharedCache.ListedPackages[linknamed] != nil:
 				// We already have it; skip.
-			case cache.GoEnv.GOOS != "js" && linknamed == "syscall/js":
+			case sharedCache.GoEnv.GOOS != "js" && linknamed == "syscall/js":
 				// GOOS-specific package.
-			case cache.GoEnv.GOOS != "darwin" && linknamed == "crypto/x509/internal/macos":
+			case sharedCache.GoEnv.GOOS != "darwin" && linknamed == "crypto/x509/internal/macos":
 				// GOOS-specific package.
 			default:
 				missing = append(missing, linknamed)
@@ -426,7 +426,7 @@ func listPackage(path string) (*listedPackage, error) {
 		if err := appendListedPackages(missing, false); err != nil {
 			panic(err) // should never happen
 		}
-		pkg, ok := cache.ListedPackages[path]
+		pkg, ok := sharedCache.ListedPackages[path]
 		if !ok {
 			panic(fmt.Sprintf("runtime listed a std package we can't find: %s", path))
 		}
@@ -453,7 +453,7 @@ func listPackage(path string) (*listedPackage, error) {
 	if pkg.ImportPath == "runtime" {
 		return pkg, nil
 	}
-	for _, dep := range cache.ListedPackages["runtime"].Deps {
+	for _, dep := range sharedCache.ListedPackages["runtime"].Deps {
 		if dep == pkg.ImportPath {
 			return pkg, nil
 		}