feat: Created the go C Wrapper files

Signed-off-by: phansGithub <[email protected]>

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/go-ozzo/ozzo-validation/v4 v4.3.0
 	github.com/google/gofuzz v1.1.0
 	github.com/google/uuid v1.3.0
+	github.com/intel/afxdp-plugins-for-kubernetes/pkg/goclient v0.0.0
 	github.com/intel/afxdp-plugins-for-kubernetes/pkg/subfunctions v0.0.0
 	github.com/pkg/errors v0.9.1
 	github.com/safchain/ethtool v0.0.0-20210803160452-9aa261dae9b1
@@ -22,3 +23,4 @@ require (
 )
 
 replace github.com/intel/afxdp-plugins-for-kubernetes/pkg/subfunctions => ./pkg/subfunctions
+replace github.com/intel/afxdp-plugins-for-kubernetes/pkg/goclient => ./pkg/goclient

pkg/cclient/README.md

@@ -0,0 +1,36 @@
+# Compiling the C Library
+
+## Creating the .h and the .so files:
+
+
+```go build -o lib_udsclient.so -buildmode=c-shared cclient.go```
+	- this creates .h and .so files from the cclient.go file.
+
+
+## Creating the .h and the .a files:
+
+```go build -o lib_udsclient.a -buildmode=c-archive ./cclient.go```
+	- this creates .h and .a files
+
+
+
+## Next steps
+
+After creating the .h and/or the .a and the .o files as described in the previous steps,
+this is how to use the functions generated by cgo
+
+``` char* GetUdsClientVersion()```
+This returns the version of our handshake on your local machine/client.
+
+```char* GetUdsServerVersion()```
+This returns the version of our handshake on the server/host.
+
+```int RequestXskMapFd(char* device)```
+This requests an Xsk map Fd for a specifed device.
+
+```int RequestBusyPoll(int busyTimeout, int busyBudget, int fd)```
+This requests a busy poll for a specific device by using it's fd, and specifying a timeout and a budget.
+
+```void CleanUpConnection()```
+After all the other functions are called, this needs to be called after all the work you need to do is done,
+so that the connection to the Uds can be cleaned up.

pkg/cclient/cclient.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"C"
+	"fmt"
+	"os"
+
+	"github.com/intel/afxdp-plugins-for-kubernetes/internal/uds"
+	"github.com/intel/afxdp-plugins-for-kubernetes/pkg/goclient"
+)
+
+func main() {
+	// Needed for cgo to generate the .h
+}
+
+var cleaner uds.CleanupFunc
+
+/*
+GetClientVersion is an exported version for c of goclient's GetClientVersion()
+*/
+//export GetUdsClientVersion
+func GetUdsClientVersion() *C.char {
+	return C.CString(goclient.GetClientVersion())
+}
+
+/*
+ServerVersion is an exported version for c of goclient's GetServerVersion()
+*/
+//export GetUdsServerVersion
+func GetUdsServerVersion() *C.char {
+	response, function, err := goclient.GetServerVersion()
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err.Error())
+		function()
+		return C.CString("-1")
+	}
+
+	cleaner = function
+
+	return C.CString(response)
+}
+
+/*
+GetXskMapFd is an exported version for c of goclient's XskMapFd()
+*/
+//export RequestXskMapFd
+func RequestXskMapFd(device *C.char) (fd C.int) {
+	fdVal, function, err := goclient.RequestXSKmapFD(C.GoString(device))
+	fd = C.int(fdVal)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err.Error())
+		function()
+		return -1
+	}
+
+	cleaner = function
+
+	return fd
+}
+
+/*
+RequestBusyPoll is an exported version for c of goclient's RequestBusyPoll()
+*/
+//export RequestBusyPoll
+func RequestBusyPoll(busyTimeout, busyBudget, fd C.int) C.int {
+	function, err := goclient.RequestBusyPoll(int(busyTimeout), int(busyBudget), int(fd))
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err.Error())
+		function()
+		return -1
+	}
+	cleaner = function
+	return 0
+}
+
+/*
+CleanUpConnection an explicit exported cgo function to cleanup a connection after calling any of the other functions.
+Pass in one of the available function names to clean up the connection after use.
+*/
+//export CleanUpConnection
+func CleanUpConnection() {
+	if cleaner == nil {
+		fmt.Println("No cleanup function available to call")
+	} else {
+		cleaner()
+	}
+}