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Diffstat (limited to 'tools/go_generics/generics.go')
| -rw-r--r-- | tools/go_generics/generics.go | 286 |
1 files changed, 0 insertions, 286 deletions
diff --git a/tools/go_generics/generics.go b/tools/go_generics/generics.go deleted file mode 100644 index 0860ca9db..000000000 --- a/tools/go_generics/generics.go +++ /dev/null @@ -1,286 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// go_generics reads a Go source file and writes a new version of that file with -// a few transformations applied to each. Namely: -// -// 1. Global types can be explicitly renamed with the -t option. For example, -// if -t=A=B is passed in, all references to A will be replaced with -// references to B; a function declaration like: -// -// func f(arg *A) -// -// would be renamed to: -// -// func f(arg *B) -// -// 2. Global type definitions and their method sets will be removed when they're -// being renamed with -t. For example, if -t=A=B is passed in, the following -// definition and methods that existed in the input file wouldn't exist at -// all in the output file: -// -// type A struct{} -// -// func (*A) f() {} -// -// 3. All global types, variables, constants and functions (not methods) are -// prefixed and suffixed based on the option -prefix and -suffix arguments. -// For example, if -suffix=A is passed in, the following globals: -// -// func f() -// type t struct{} -// -// would be renamed to: -// -// func fA() -// type tA struct{} -// -// Some special tags are also modified. For example: -// -// "state:.(t)" -// -// would become: -// -// "state:.(tA)" -// -// 4. The package is renamed to the value via the -p argument. -// 5. Value of constants can be modified with -c argument. -// -// Note that not just the top-level declarations are renamed, all references to -// them are also properly renamed as well, taking into account visibility rules -// and shadowing. For example, if -suffix=A is passed in, the following: -// -// var b = 100 -// -// func f() { -// g(b) -// b := 0 -// g(b) -// } -// -// Would be replaced with: -// -// var bA = 100 -// -// func f() { -// g(bA) -// b := 0 -// g(b) -// } -// -// Note that the second call to g() kept "b" as an argument because it refers to -// the local variable "b". -// -// Note that go_generics can handle anonymous fields with renamed types if -// -anon is passed in, however it does not perform strict checking on parameter -// types that share the same name as the global type and therefore will rename -// them as well. -// -// You can see an example in the tools/go_generics/generics_tests/interface test. -package main - -import ( - "bytes" - "flag" - "fmt" - "go/ast" - "go/format" - "go/parser" - "go/token" - "io/ioutil" - "os" - "regexp" - "strings" - - "gvisor.dev/gvisor/tools/go_generics/globals" -) - -var ( - input = flag.String("i", "", "input `file`") - output = flag.String("o", "", "output `file`") - suffix = flag.String("suffix", "", "`suffix` to add to each global symbol") - prefix = flag.String("prefix", "", "`prefix` to add to each global symbol") - packageName = flag.String("p", "main", "output package `name`") - printAST = flag.Bool("ast", false, "prints the AST") - processAnon = flag.Bool("anon", false, "process anonymous fields") - types = make(mapValue) - consts = make(mapValue) - imports = make(mapValue) -) - -// mapValue implements flag.Value. We use a mapValue flag instead of a regular -// string flag when we want to allow more than one instance of the flag. For -// example, we allow several "-t A=B" arguments, and will rename them all. -type mapValue map[string]string - -func (m mapValue) String() string { - var b bytes.Buffer - first := true - for k, v := range m { - if !first { - b.WriteRune(',') - } else { - first = false - } - b.WriteString(k) - b.WriteRune('=') - b.WriteString(v) - } - return b.String() -} - -func (m mapValue) Set(s string) error { - sep := strings.Index(s, "=") - if sep == -1 { - return fmt.Errorf("missing '=' from '%s'", s) - } - - m[s[:sep]] = s[sep+1:] - - return nil -} - -// stateTagRegexp matches against the 'typed' state tags. -var stateTagRegexp = regexp.MustCompile(`^(.*[^a-z0-9_])state:"\.\(([^\)]*)\)"(.*)$`) - -var identifierRegexp = regexp.MustCompile(`^(.*[^a-zA-Z_])([a-zA-Z_][a-zA-Z0-9_]*)(.*)$`) - -func main() { - flag.Usage = func() { - fmt.Fprintf(os.Stderr, "Usage: %s [options]\n", os.Args[0]) - flag.PrintDefaults() - } - - flag.Var(types, "t", "rename type A to B when `A=B` is passed in. Multiple such mappings are allowed.") - flag.Var(consts, "c", "reassign constant A to value B when `A=B` is passed in. Multiple such mappings are allowed.") - flag.Var(imports, "import", "specifies the import libraries to use when types are not local. `name=path` specifies that 'name', used in types as name.type, refers to the package living in 'path'.") - flag.Parse() - - if *input == "" || *output == "" { - flag.Usage() - os.Exit(1) - } - - // Parse the input file. - fset := token.NewFileSet() - f, err := parser.ParseFile(fset, *input, nil, parser.ParseComments|parser.DeclarationErrors|parser.SpuriousErrors) - if err != nil { - fmt.Fprintf(os.Stderr, "%v\n", err) - os.Exit(1) - } - - // Print the AST if requested. - if *printAST { - ast.Print(fset, f) - } - - cmap := ast.NewCommentMap(fset, f, f.Comments) - - // Update imports based on what's used in types and consts. - maps := []mapValue{types, consts} - importDecl, err := updateImports(maps, imports) - if err != nil { - fmt.Fprintf(os.Stderr, "%v\n", err) - os.Exit(1) - } - types = maps[0] - consts = maps[1] - - // Reassign all specified constants. - for _, decl := range f.Decls { - d, ok := decl.(*ast.GenDecl) - if !ok || d.Tok != token.CONST { - continue - } - - for _, gs := range d.Specs { - s := gs.(*ast.ValueSpec) - for i, id := range s.Names { - if n, ok := consts[id.Name]; ok { - s.Values[i] = &ast.BasicLit{Value: n} - } - } - } - } - - // Go through all globals and their uses in the AST and rename the types - // with explicitly provided names, and rename all types, variables, - // consts and functions with the provided prefix and suffix. - globals.Visit(fset, f, func(ident *ast.Ident, kind globals.SymKind) { - if n, ok := types[ident.Name]; ok && kind == globals.KindType { - ident.Name = n - } else { - switch kind { - case globals.KindType, globals.KindVar, globals.KindConst, globals.KindFunction: - if ident.Name != "_" { - ident.Name = *prefix + ident.Name + *suffix - } - case globals.KindTag: - // Modify the state tag appropriately. - if m := stateTagRegexp.FindStringSubmatch(ident.Name); m != nil { - if t := identifierRegexp.FindStringSubmatch(m[2]); t != nil { - typeName := *prefix + t[2] + *suffix - if n, ok := types[t[2]]; ok { - typeName = n - } - ident.Name = m[1] + `state:".(` + t[1] + typeName + t[3] + `)"` + m[3] - } - } - } - } - }, *processAnon) - - // Remove the definition of all types that are being remapped. - set := make(typeSet) - for _, v := range types { - set[v] = struct{}{} - } - removeTypes(set, f) - - // Add the new imports, if any, to the top. - if importDecl != nil { - newDecls := make([]ast.Decl, 0, len(f.Decls)+1) - newDecls = append(newDecls, importDecl) - newDecls = append(newDecls, f.Decls...) - f.Decls = newDecls - } - - // Update comments to remove the ones potentially associated with the - // type T that we removed. - f.Comments = cmap.Filter(f).Comments() - - // If there are file (package) comments, delete them. - if f.Doc != nil { - for i, cg := range f.Comments { - if cg == f.Doc { - f.Comments = append(f.Comments[:i], f.Comments[i+1:]...) - break - } - } - } - - // Write the output file. - f.Name.Name = *packageName - - var buf bytes.Buffer - if err := format.Node(&buf, fset, f); err != nil { - fmt.Fprintf(os.Stderr, "%v\n", err) - os.Exit(1) - } - - if err := ioutil.WriteFile(*output, buf.Bytes(), 0644); err != nil { - fmt.Fprintf(os.Stderr, "%v\n", err) - os.Exit(1) - } -} |