README
¶
About
Trap is the core the xgo runtime.
When a function is called, it's control flow will first be transferred to Trap.
Then Trap check if there is any interceptor, including system defined interceptors like Mock and Trace, as well as user defined interceptors by calling Trap.AddInterceptor().
If any, it will then forward call to these interceptors, until all interceptors returned, or some interceptor returns trap.ErrAbort in the middle.
Inspect(f)
the trap.Inspect(fn) implements a way to retrieve func info.
It has different internal paths for these function types:
- package level function
- PC lookup
- struct method
-fmsuffix checkstruct.methodproto existence check- dynamic retrieval
- interface method
-fmsuffix check- interface proto existence check
- dynamic retrieval
- closure
- closure is registered using IR
- PC lookup
- generic function
- fullName parsing to de-generic
- generic template existence check
- no dynamic retrieval since no recv, but is legal to do so
- generic struct method
-fmsuffix check- fullName parsing to de-generic
- generic method template existence check
- dynamic retrieval just for receiver
- generic interface method
- to be supported
Documentation
¶
Index ¶
- Constants
- Variables
- func AddFuncInfoInterceptor(f *core.FuncInfo, interceptor *Interceptor) func()
- func AddFuncInterceptor(f interface{}, interceptor *Interceptor) func()
- func AddInterceptor(interceptor *Interceptor) func()
- func AddInterceptorHead(interceptor *Interceptor) func()
- func Direct(fn func())
- func GetTrappingPC() uintptr
- func Ignore(f interface{})
- func Inspect(f interface{}) (recvPtr interface{}, funcInfo *core.FuncInfo)
- func InspectPC(f interface{}) (recvPtr interface{}, funcInfo *core.FuncInfo, funcPC uintptr, ...)
- func Skip()
- func WithFuncOverride(funcInfo *core.FuncInfo, interceptor *Interceptor, f func())
- func WithInterceptor(interceptor *Interceptor, f func())
- func WithOverride(interceptor *Interceptor, f func())
- type Interceptor
Constants ¶
const ClosureHasFunc = true
const GenericImplIsClosure = false
Variables ¶
var ErrAbort error = errors.New("abort trap interceptor")
var ErrSkip error = errors.New("skip trap interceptor")
Functions ¶
func AddFuncInfoInterceptor ¶ added in v1.0.23
func AddFuncInfoInterceptor(f *core.FuncInfo, interceptor *Interceptor) func()
func AddFuncInterceptor ¶ added in v1.0.23
func AddFuncInterceptor(f interface{}, interceptor *Interceptor) func()
AddFuncInterceptor add func interceptor, allowing f to be re-entrant
func AddInterceptor ¶
func AddInterceptor(interceptor *Interceptor) func()
AddInterceptor add a general interceptor, disallowing re-entrant
func AddInterceptorHead ¶ added in v1.0.22
func AddInterceptorHead(interceptor *Interceptor) func()
func Direct ¶ added in v1.0.16
func Direct(fn func())
Direct make a call to fn, without any trap and mock interceptors
func GetTrappingPC ¶ added in v1.0.10
func GetTrappingPC() uintptr
func Inspect ¶ added in v1.0.8
Inspect make a call to f to capture its receiver pointer if it is bound method It can be used to get the unwrapped innermost function of a method wrapper. if f is a bound method, then guaranteed that recvPtr cannot be nil
func Skip ¶
func Skip()
Skip serves as mark to tell xgo not insert trap instructions for the function that calls Skip() NOTE: the function body is intenionally leave empty as trap.Skip() is just a mark that makes sense at compile time.
func WithFuncOverride ¶ added in v1.0.23
func WithFuncOverride(funcInfo *core.FuncInfo, interceptor *Interceptor, f func())
func WithInterceptor ¶
func WithInterceptor(interceptor *Interceptor, f func())
WithInterceptor executes given f with interceptor setup. It can be used from init phase safely. it clears the interceptor after f finishes. the interceptor will be added to head, so it will gets firstly invoked. f cannot be nil.
NOTE: the implementation uses addLocalInterceptor even from init because it will be soon cleared without causing concurrent issues.
func WithOverride ¶ added in v1.0.20
func WithOverride(interceptor *Interceptor, f func())
WithOverride override local and global interceptors in current goroutine temporarily, it returns a function that can be used to cancel the override.
Source Files