expose options related to caching

(cherry picked from commit 8b51d0d)

Author: lhchavez

settings.go

@@ -18,10 +18,20 @@ int _go_git_opts_set_size_t(int opt, size_t val)
     return git_libgit2_opts(opt, val);
 }
 
+int _go_git_opts_set_cache_object_limit(git_object_t type, size_t size)
+{
+    return git_libgit2_opts(GIT_OPT_SET_CACHE_OBJECT_LIMIT, type, size);
+}
+
 int _go_git_opts_get_size_t(int opt, size_t *val)
 {
     return git_libgit2_opts(opt, val);
 }
+
+int _go_git_opts_get_size_t_size_t(int opt, size_t *val1, size_t *val2)
+{
+    return git_libgit2_opts(opt, val1, val2);
+}
 */
 import "C"
 import (
@@ -75,6 +85,34 @@ func SetMwindowMappedLimit(size int) error {
 	return setSizet(C.GIT_OPT_SET_MWINDOW_MAPPED_LIMIT, size)
 }
 
+func EnableCaching(enabled bool) error {
+	if enabled {
+		return setSizet(C.GIT_OPT_ENABLE_CACHING, 1)
+	} else {
+		return setSizet(C.GIT_OPT_ENABLE_CACHING, 0)
+	}
+}
+
+func GetCachedMemory() (current int, allowed int, err error) {
+	return getSizetSizet(C.GIT_OPT_GET_CACHED_MEMORY)
+}
+
+func SetCacheMaxSize(maxSize int) error {
+	return setSizet(C.GIT_OPT_SET_CACHE_MAX_SIZE, maxSize)
+}
+
+func SetCacheObjectLimit(objectType ObjectType, size int) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	err := C._go_git_opts_set_cache_object_limit(C.git_object_t(objectType), C.size_t(size))
+	if err < 0 {
+		return MakeGitError(err)
+	}
+
+	return nil
+}
+
 func getSizet(opt C.int) (int, error) {
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()
@@ -88,6 +126,19 @@ func getSizet(opt C.int) (int, error) {
 	return int(val), nil
 }
 
+func getSizetSizet(opt C.int) (int, int, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	var val1, val2 C.size_t
+	err := C._go_git_opts_get_size_t_size_t(opt, &val1, &val2)
+	if err < 0 {
+		return 0, 0, MakeGitError(err)
+	}
+
+	return int(val1), int(val2), nil
+}
+
 func setSizet(opt C.int, val int) error {
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()

settings_test.go

@@ -48,3 +48,36 @@ func TestMmapSizes(t *testing.T) {
 		t.Fatal("Sizes don't match")
 	}
 }
+
+func TestEnableCaching(t *testing.T) {
+	err := EnableCaching(false)
+	checkFatal(t, err)
+
+	err = EnableCaching(true)
+	checkFatal(t, err)
+}
+
+func TestGetCachedMemory(t *testing.T) {
+	current, allowed, err := GetCachedMemory()
+	checkFatal(t, err)
+
+	if current < 0 {
+		t.Fatal("current < 0")
+	}
+
+	if allowed < 0 {
+		t.Fatal("allowed < 0")
+	}
+}
+
+func TestSetCacheMaxSize(t *testing.T) {
+	err := SetCacheMaxSize(0)
+	checkFatal(t, err)
+
+	err = SetCacheMaxSize(1024 * 1024)
+	checkFatal(t, err)
+
+	// revert to default 256MB
+	err = SetCacheMaxSize(256 * 1024 * 1024)
+	checkFatal(t, err)
+}