+++ /dev/null
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// The unmarshal package defines an Analyzer that checks for passing
-// non-pointer or non-interface types to unmarshal and decode functions.
-package unmarshal
-
-import (
- "go/ast"
- "go/types"
-
- "golang.org/x/tools/go/analysis"
- "golang.org/x/tools/go/analysis/passes/inspect"
- "golang.org/x/tools/go/ast/inspector"
- "golang.org/x/tools/go/types/typeutil"
-)
-
-const Doc = `report passing non-pointer or non-interface values to unmarshal
-
-The unmarshal analysis reports calls to functions such as json.Unmarshal
-in which the argument type is not a pointer or an interface.`
-
-var Analyzer = &analysis.Analyzer{
- Name: "unmarshal",
- Doc: Doc,
- Requires: []*analysis.Analyzer{inspect.Analyzer},
- Run: run,
-}
-
-func run(pass *analysis.Pass) (interface{}, error) {
- switch pass.Pkg.Path() {
- case "encoding/gob", "encoding/json", "encoding/xml", "encoding/asn1":
- // These packages know how to use their own APIs.
- // Sometimes they are testing what happens to incorrect programs.
- return nil, nil
- }
-
- inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
-
- nodeFilter := []ast.Node{
- (*ast.CallExpr)(nil),
- }
- inspect.Preorder(nodeFilter, func(n ast.Node) {
- call := n.(*ast.CallExpr)
- fn := typeutil.StaticCallee(pass.TypesInfo, call)
- if fn == nil {
- return // not a static call
- }
-
- // Classify the callee (without allocating memory).
- argidx := -1
- recv := fn.Type().(*types.Signature).Recv()
- if fn.Name() == "Unmarshal" && recv == nil {
- // "encoding/json".Unmarshal
- // "encoding/xml".Unmarshal
- // "encoding/asn1".Unmarshal
- switch fn.Pkg().Path() {
- case "encoding/json", "encoding/xml", "encoding/asn1":
- argidx = 1 // func([]byte, interface{})
- }
- } else if fn.Name() == "Decode" && recv != nil {
- // (*"encoding/json".Decoder).Decode
- // (* "encoding/gob".Decoder).Decode
- // (* "encoding/xml".Decoder).Decode
- t := recv.Type()
- if ptr, ok := t.(*types.Pointer); ok {
- t = ptr.Elem()
- }
- tname := t.(*types.Named).Obj()
- if tname.Name() == "Decoder" {
- switch tname.Pkg().Path() {
- case "encoding/json", "encoding/xml", "encoding/gob":
- argidx = 0 // func(interface{})
- }
- }
- }
- if argidx < 0 {
- return // not a function we are interested in
- }
-
- if len(call.Args) < argidx+1 {
- return // not enough arguments, e.g. called with return values of another function
- }
-
- t := pass.TypesInfo.Types[call.Args[argidx]].Type
- switch t.Underlying().(type) {
- case *types.Pointer, *types.Interface:
- return
- }
-
- switch argidx {
- case 0:
- pass.Reportf(call.Lparen, "call of %s passes non-pointer", fn.Name())
- case 1:
- pass.Reportf(call.Lparen, "call of %s passes non-pointer as second argument", fn.Name())
- }
- })
- return nil, nil
-}