cogger c wrapper

cpp.go

package main

import "C"
import (
	"fmt"
	"os"
	"unsafe"

	"github.com/airbusgeo/cogger"
	"github.com/google/tiff"
)

//export cogify
func cogify(out *C.char, in **C.char, nin C.int) C.int {
	infiles := (*[1 << 28]unsafe.Pointer)(unsafe.Pointer(in))[:nin:nin]
	readers := make([]tiff.ReadAtReadSeeker, len(infiles))
	output := C.GoString(out)
	for i, cinput := range infiles {
		input := C.GoString((*C.char)(cinput))
		topFile, err := os.Open(input)
		if err != nil {
			fmt.Fprintf(os.Stderr, "open %s: %v", input, err)
			return 1
		}
		defer topFile.Close()
		readers[i] = topFile
	}
	outf, err := os.Create(output)
	if err != nil {
		fmt.Fprintf(os.Stderr, "create %s: %v", output, err)
		return 1
	}
	err = cogger.Rewrite(outf, readers...)
	if err != nil {
		fmt.Fprintf(os.Stderr, "mucog write: %v", err)
		return 1
	}
	err = outf.Close()
	if err != nil {
		fmt.Fprintf(os.Stderr, "close %s: %v", output, err)
		return 1
	}
	return 0
}

func main() {}

main.c

extern int cogify(char* out, char** in, int nin);

int main(int argc, char **argv) {
   char *infiles[] = {
      "../testdata/exttest.tif",
      "../testdata/exttest.tif.2",
   };
   cogify("output.tif", infiles,2);
}

Makefile

build:
	go build -o cogify.so -buildmode=c-shared .
	gcc -o main main.c cogify.so