Add staticcheck tool

vendor/honnef.co/go/tools/staticcheck/sa1016/sa1016.go

@@ -0,0 +1,115 @@
+package sa1016
+
+import (
+	"fmt"
+	"go/ast"
+
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/edit"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+	"honnef.co/go/tools/pattern"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "SA1016",
+		Run:      run,
+		Requires: code.RequiredAnalyzers,
+	},
+	Doc: &lint.RawDocumentation{
+		Title: `Trapping a signal that cannot be trapped`,
+		Text: `Not all signals can be intercepted by a process. Specifically, on
+UNIX-like systems, the \'syscall.SIGKILL\' and \'syscall.SIGSTOP\' signals are
+never passed to the process, but instead handled directly by the
+kernel. It is therefore pointless to try and handle these signals.`,
+		Since:    "2017.1",
+		Severity: lint.SeverityWarning,
+		MergeIf:  lint.MergeIfAny,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+var query = pattern.MustParse(`
+	(CallExpr
+		(Symbol
+			(Or
+				"os/signal.Ignore"
+				"os/signal.Notify"
+				"os/signal.Reset"))
+		_)`)
+
+func run(pass *analysis.Pass) (any, error) {
+	isSignal := func(pass *analysis.Pass, expr ast.Expr, name string) bool {
+		if expr, ok := expr.(*ast.SelectorExpr); ok {
+			return code.SelectorName(pass, expr) == name
+		} else {
+			return false
+		}
+	}
+
+	for node := range code.Matches(pass, query) {
+		call := node.(*ast.CallExpr)
+		hasSigterm := false
+		for _, arg := range call.Args {
+			if conv, ok := arg.(*ast.CallExpr); ok && isSignal(pass, conv.Fun, "os.Signal") {
+				arg = conv.Args[0]
+			}
+
+			if isSignal(pass, arg, "syscall.SIGTERM") {
+				hasSigterm = true
+				break
+			}
+
+		}
+		for i, arg := range call.Args {
+			if conv, ok := arg.(*ast.CallExpr); ok && isSignal(pass, conv.Fun, "os.Signal") {
+				arg = conv.Args[0]
+			}
+
+			if isSignal(pass, arg, "os.Kill") || isSignal(pass, arg, "syscall.SIGKILL") {
+				var fixes []analysis.SuggestedFix
+				if !hasSigterm {
+					nargs := make([]ast.Expr, len(call.Args))
+					for j, a := range call.Args {
+						if i == j {
+							nargs[j] = edit.Selector("syscall", "SIGTERM")
+						} else {
+							nargs[j] = a
+						}
+					}
+					ncall := *call
+					ncall.Args = nargs
+					fixes = append(fixes, edit.Fix(fmt.Sprintf("Use syscall.SIGTERM instead of %s", report.Render(pass, arg)), edit.ReplaceWithNode(pass.Fset, call, &ncall)))
+				}
+				nargs := make([]ast.Expr, 0, len(call.Args))
+				for j, a := range call.Args {
+					if i == j {
+						continue
+					}
+					nargs = append(nargs, a)
+				}
+				ncall := *call
+				ncall.Args = nargs
+				fixes = append(fixes, edit.Fix(fmt.Sprintf("Remove %s from list of arguments", report.Render(pass, arg)), edit.ReplaceWithNode(pass.Fset, call, &ncall)))
+				report.Report(pass, arg, fmt.Sprintf("%s cannot be trapped (did you mean syscall.SIGTERM?)", report.Render(pass, arg)), report.Fixes(fixes...))
+			}
+			if isSignal(pass, arg, "syscall.SIGSTOP") {
+				nargs := make([]ast.Expr, 0, len(call.Args)-1)
+				for j, a := range call.Args {
+					if i == j {
+						continue
+					}
+					nargs = append(nargs, a)
+				}
+				ncall := *call
+				ncall.Args = nargs
+				report.Report(pass, arg, "syscall.SIGSTOP cannot be trapped", report.Fixes(edit.Fix("Remove syscall.SIGSTOP from list of arguments", edit.ReplaceWithNode(pass.Fset, call, &ncall))))
+			}
+		}
+	}
+	return nil, nil
+}