/
engine.go
264 lines (233 loc) · 6.22 KB
/
engine.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
package ruleguard
import (
"errors"
"fmt"
"go/ast"
"go/build"
"go/token"
"go/types"
"io"
"io/ioutil"
"os"
"sort"
"strings"
"sync"
"github.com/quasilyte/go-ruleguard/internal/goenv"
"github.com/quasilyte/go-ruleguard/ruleguard/ir"
"github.com/quasilyte/go-ruleguard/ruleguard/quasigo"
"github.com/quasilyte/go-ruleguard/ruleguard/typematch"
"github.com/quasilyte/stdinfo"
)
type engine struct {
state *engineState
ruleSet *goRuleSet
}
func newEngine() *engine {
return &engine{
state: newEngineState(),
}
}
func (e *engine) LoadedGroups() []GoRuleGroup {
result := make([]GoRuleGroup, 0, len(e.ruleSet.groups))
for _, g := range e.ruleSet.groups {
result = append(result, *g)
}
sort.Slice(result, func(i, j int) bool {
return result[i].Name < result[j].Name
})
return result
}
func (e *engine) Load(ctx *LoadContext, buildContext *build.Context, filename string, r io.Reader) error {
data, err := ioutil.ReadAll(r)
if err != nil {
return err
}
imp := newGoImporter(e.state, goImporterConfig{
fset: ctx.Fset,
debugImports: ctx.DebugImports,
debugPrint: ctx.DebugPrint,
buildContext: buildContext,
})
irfile, pkg, err := convertAST(ctx, imp, filename, data)
if err != nil {
return err
}
config := irLoaderConfig{
state: e.state,
pkg: pkg,
ctx: ctx,
importer: imp,
itab: typematch.NewImportsTab(stdinfo.PackagesList),
gogrepFset: token.NewFileSet(),
}
l := newIRLoader(config)
rset, err := l.LoadFile(filename, irfile)
if err != nil {
return err
}
if e.ruleSet == nil {
e.ruleSet = rset
} else {
combinedRuleSet, err := mergeRuleSets([]*goRuleSet{e.ruleSet, rset})
if err != nil {
return err
}
e.ruleSet = combinedRuleSet
}
return nil
}
func (e *engine) LoadFromIR(ctx *LoadContext, buildContext *build.Context, filename string, f *ir.File) error {
imp := newGoImporter(e.state, goImporterConfig{
fset: ctx.Fset,
debugImports: ctx.DebugImports,
debugPrint: ctx.DebugPrint,
buildContext: buildContext,
})
config := irLoaderConfig{
state: e.state,
ctx: ctx,
importer: imp,
itab: typematch.NewImportsTab(stdinfo.PackagesList),
gogrepFset: token.NewFileSet(),
}
l := newIRLoader(config)
rset, err := l.LoadFile(filename, f)
if err != nil {
return err
}
if e.ruleSet == nil {
e.ruleSet = rset
} else {
combinedRuleSet, err := mergeRuleSets([]*goRuleSet{e.ruleSet, rset})
if err != nil {
return err
}
e.ruleSet = combinedRuleSet
}
return nil
}
func (e *engine) Run(ctx *RunContext, buildContext *build.Context, f *ast.File) error {
if e.ruleSet == nil {
return errors.New("used Run() with an empty rule set; forgot to call Load() first?")
}
rset := e.ruleSet
return newRulesRunner(ctx, buildContext, e.state, rset).run(f)
}
// engineState is a shared state inside the engine.
type engineState struct {
env *quasigo.Env
typeByFQNMu sync.RWMutex
typeByFQN map[string]types.Type
pkgCacheMu sync.RWMutex
// pkgCache contains all imported packages, from any importer.
pkgCache map[string]*types.Package
}
func newEngineState() *engineState {
env := quasigo.NewEnv()
state := &engineState{
env: env,
pkgCache: make(map[string]*types.Package),
typeByFQN: map[string]types.Type{},
}
for key, typ := range typeByName {
state.typeByFQN[key] = typ
}
initEnv(state, env)
return state
}
func (state *engineState) GetCachedPackage(pkgPath string) *types.Package {
state.pkgCacheMu.RLock()
pkg := state.pkgCache[pkgPath]
state.pkgCacheMu.RUnlock()
return pkg
}
func (state *engineState) AddCachedPackage(pkgPath string, pkg *types.Package) {
state.pkgCacheMu.Lock()
state.addCachedPackage(pkgPath, pkg)
state.pkgCacheMu.Unlock()
}
func (state *engineState) addCachedPackage(pkgPath string, pkg *types.Package) {
state.pkgCache[pkgPath] = pkg
// Also add all complete packages that are dependencies of the pkg.
// This way we cache more and avoid duplicated package loading
// which can lead to typechecking issues.
//
// Note that it does not increase our memory consumption
// as these packages are reachable via pkg, so they'll
// not be freed by GC anyway.
for _, imported := range pkg.Imports() {
if imported.Complete() {
state.addCachedPackage(imported.Path(), imported)
}
}
}
func (state *engineState) FindType(importer *goImporter, currentPkg *types.Package, fqn string) (types.Type, error) {
// TODO(quasilyte): we can pre-populate the cache during the Load() phase.
// If we inspect the AST of a user function, all constant FQN can be preloaded.
// It could be a good thing as Load() is not expected to be executed in
// concurrent environment, so write-locking is not a big deal there.
state.typeByFQNMu.RLock()
cachedType, ok := state.typeByFQN[fqn]
state.typeByFQNMu.RUnlock()
if ok {
return cachedType, nil
}
// Code below is under a write critical section.
state.typeByFQNMu.Lock()
defer state.typeByFQNMu.Unlock()
typ, err := state.findTypeNoCache(importer, currentPkg, fqn)
if err != nil {
return nil, err
}
state.typeByFQN[fqn] = typ
return typ, nil
}
func (state *engineState) findTypeNoCache(importer *goImporter, currentPkg *types.Package, fqn string) (types.Type, error) {
pos := strings.LastIndexByte(fqn, '.')
if pos == -1 {
return nil, fmt.Errorf("%s is not a valid FQN", fqn)
}
pkgPath := fqn[:pos]
objectName := fqn[pos+1:]
var pkg *types.Package
if currentPkg != nil {
if directDep := findDependency(currentPkg, pkgPath); directDep != nil {
pkg = directDep
}
}
if pkg == nil {
loadedPkg, err := importer.Import(pkgPath)
if err != nil {
return nil, err
}
pkg = loadedPkg
}
obj := pkg.Scope().Lookup(objectName)
if obj == nil {
return nil, fmt.Errorf("%s is not found in %s", objectName, pkgPath)
}
typ := obj.Type()
state.typeByFQN[fqn] = typ
return typ, nil
}
func inferBuildContext() *build.Context {
// Inherit most fields from the build.Default.
ctx := build.Default
env, err := goenv.Read()
if err != nil {
return &ctx
}
ctx.GOROOT = env["GOROOT"]
ctx.GOPATH = env["GOPATH"]
ctx.GOARCH = env["GOARCH"]
ctx.GOOS = env["GOOS"]
switch os.Getenv("CGO_ENABLED") {
case "0":
ctx.CgoEnabled = false
case "1":
ctx.CgoEnabled = true
default:
ctx.CgoEnabled = env["CGO_ENABLED"] == "1"
}
return &ctx
}