go: lints & cleanup

Remove dead code, make 'go list' happy.

go.mod

@@ -0,0 +1,3 @@
+module main
+
+go 1.20

main.c

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:build ignore
 #include <sys/types.h>
 #include <stdio.h>
 #include <string.h>

main.go

@@ -16,12 +16,8 @@ limitations under the License.
 package main
 
 import (
-	"fmt"
 	"io"
-	"log"
 	"os"
-	"runtime"
-	"runtime/pprof"
 )
 
 const BUF = 64 * 4096
@@ -86,30 +82,3 @@ func scan(input io.Reader) {
 func main() {
 	scan(os.Stdin)
 }
-
-func pmain() {
-	c, err := os.Create("sha1scan.cpu.prof")
-	if err != nil {
-		log.Fatal("could not create CPU profile: ", err)
-	}
-	defer c.Close()
-	if err := pprof.StartCPUProfile(c); err != nil {
-		log.Fatal("could not start CPU profile: ", err)
-	}
-
-	scan(os.Stdin)
-
-	pprof.StopCPUProfile()
-	runtime.GC() // get up-to-date statistics
-
-	for _, p := range pprof.Profiles() {
-		m, err := os.Create(fmt.Sprintf("sha1scan.%s.prof", p.Name()))
-		if err != nil {
-			log.Fatalf("could not create %s profile: ", p.Name(), err)
-		}
-		defer m.Close()
-		if err := p.WriteTo(m, 1); err != nil {
-			log.Fatal("could not write %s profile: ", p.Name(), err)
-		}
-	}
-}