Add support for ignore

ignore.go

@@ -0,0 +1,51 @@
+package git
+
+/*
+#include <git2.h>
+*/
+import "C"
+import (
+	"runtime"
+	"unsafe"
+)
+
+func (v *Repository) AddIgnoreRule(rules string) error {
+	crules := C.CString(rules)
+	defer C.free(unsafe.Pointer(crules))
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ret := C.git_ignore_add_rule(v.ptr, crules)
+	if ret < 0 {
+		return MakeGitError(ret)
+	}
+	return nil
+}
+
+func (v *Repository) ClearInternalIgnoreRules() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ret := C.git_ignore_clear_internal_rules(v.ptr)
+	if ret < 0 {
+		return MakeGitError(ret)
+	}
+	return nil
+}
+
+func (v *Repository) IsPathIgnored(path string) (bool, error) {
+	var ignored C.int
+
+	cpath := C.CString(path)
+	defer C.free(unsafe.Pointer(cpath))
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ret := C.git_ignore_path_is_ignored(&ignored, v.ptr, cpath)
+	if ret < 0 {
+		return false, MakeGitError(ret)
+	}
+	return ignored == 1, nil
+}