RosettaCodeData/Task/Call-a-function-in-a-shared.../Go/call-a-function-in-a-shared...

53 lines
1.1 KiB
Go

package main
/*
#cgo LDFLAGS: -ldl
#include <stdlib.h>
#include <dlfcn.h>
typedef int (*someFunc) (const char *s);
int bridge_someFunc(someFunc f, const char *s) {
return f(s);
}
*/
import "C"
import (
"fmt"
"os"
"unsafe"
)
var handle = -1
func myOpenImage(s string) int {
fmt.Fprintf(os.Stderr, "internal openImage opens %s...\n", s)
handle++
return handle
}
func main() {
libpath := C.CString("./fakeimglib.so")
defer C.free(unsafe.Pointer(libpath))
imglib := C.dlopen(libpath, C.RTLD_LAZY)
var imghandle int
if imglib != nil {
openimage := C.CString("openimage")
defer C.free(unsafe.Pointer(openimage))
fp := C.dlsym(imglib, openimage)
if fp != nil {
fi := C.CString("fake.img")
defer C.free(unsafe.Pointer(fi))
imghandle = int(C.bridge_someFunc(C.someFunc(fp), fi))
} else {
imghandle = myOpenImage("fake.img")
}
C.dlclose(imglib)
} else {
imghandle = myOpenImage("fake.img")
}
fmt.Printf("opened with handle %d\n", imghandle)
}