Feat symbol validation

[fishingfly]

#165

How to use

yaml file will add a Validations filed in TRANSLATOR:

---
GENERATOR:
  PackageName: device
  PackageDescription: "Package Device bindings"
  PackageLicense: |-
  Includes: ["device.h", "device_internal.h"]
  FlagGroups:
    - {name: "LDFLAGS", flags: ["-ldevice"]}
  Options:
    SafeStrings: true
PARSER:
  IncludePaths: ["."]
  SourcesPaths: ["device.h", "device_internal.h"]
TRANSLATOR:
  ....
+  Validations:
+     - validatefunc: libdevice.Lookup
+       ret: ERROR_NOT_SUPPORTED
+       matchedfunc: ^(?!.*deviceErrorString).*$
+     - validatefunc: libdevice.Lookup
+        ret: ERROR_NOT_SUPPORTED_STRING
+        matchedfunc: ^deviceErrorString

and the generated go function codes as follows:

// deviceErrorString function as declared in device/device.h
func deviceErrorString(Result Return) string {
+       if libdevice.Lookup("deviceGetMode") != nil {
+		return ERROR_NOT_SUPPORTED_STRING
+	}
	cResult, cResultAllocMap := (C.DeviceReturn)(Result), cgoAllocsUnknown
	__ret := C.deviceErrorString(cResult)
	runtime.KeepAlive(cResultAllocMap)
	__v := packPCharString(__ret)
	return __v
}

// deviceGetMode function as declared in device/device.h
func deviceGetMode(Device *Device, Mode Mode) Return {
+	if libdevice.Lookup("deviceGetMode") != nil {
+		return ERROR_NOT_SUPPORTED
+	}
	cDevice, cDeviceAllocMap := (*C.Device)(unsafe.Pointer(Device)), cgoAllocsUnknown
	cMode, cModeAllocMap := (C.Mode)(Mode), cgoAllocsUnknown
	__ret := C.deviceGetMode(cDevice, cMode)
	runtime.KeepAlive(cModeAllocMap)
	runtime.KeepAlive(cDeviceAllocMap)
	__v := (Return)(__ret)
	return __v
}

• validatefunc field is used to specify the lookup function which defined bu user.
• ret filed is used to specify the ret value which defined by user.
• matchedfunc field is used to specify a full-featured regex to match functions or skip functions.

[xlab]

Hello! Thanks for contribution, the feature looks really interesting. However, is it possible to avoid adding vendor dir? The project uses go.mod system. Otherwise it makes PR big and codebase becomes confusing.

[yeahdongcn]

It is super useful to me as various versions of a library coexist in my production environment. The go client always consumes the latest binding (shipping with container), while in runtime, certain APIs may not exist in the runtime library.

[fishingfly]

Hello! Thanks for contribution, the feature looks really interesting. However, is it possible to avoid adding vendor dir? The project uses go.mod system. Otherwise it makes PR big and codebase becomes confusing.

ACK