func()

in tool/instrument/trampoline.go [223:262]

• 35 lines of code
• 7 McCabe index (conditional complexity)

func (rp *RuleProcessor) callOnExitHook(t *resource.InstFuncRule, traits []ParamTrait) error {
	// The actual parameter list of hook function should be the same as the
	// target function
	if rp.exact {
		util.Assert(len(traits) == len(rp.onExitHookFunc.Type.Params.List),
			"mismatched param traits")
	}
	// Hook: 	   func onExitFoo(ctx* CallContext, p*[]int)
	// Trampoline: func OtelOnExitTrampoline_foo(ctx* CallContext, p *[]int)
	var args []dst.Expr
	for idx, field := range rp.onExitHookFunc.Type.Params.List {
		if idx == 0 {
			args = append(args, dst.NewIdent(TrampolineCallContextName))
			if !rp.exact {
				// Generic hook function, no need to process parameters
				break
			}
			continue
		}
		trait := traits[idx]
		for _, name := range field.Names { // syntax of n1,n2 type
			if trait.IsVaradic {
				arg := util.DereferenceOf(util.Ident(name.Name + "..."))
				args = append(args, arg)
			} else {
				arg := util.DereferenceOf(dst.NewIdent(name.Name))
				args = append(args, arg)
			}
		}
	}
	fnName := makeOnXName(t, false)
	call := util.ExprStmt(util.CallTo(fnName, args))
	iff := util.IfNotNilStmt(
		dst.NewIdent(fnName),
		util.Block(call),
		nil,
	)
	insertAtEnd(rp.onExitHookFunc, iff)
	return nil
}