Guard the file cloning behind a user configuration option

Signed-off-by: Phil Krylov <phil@krylov.eu>

Author: tuffnatty

lib/global.c

@@ -109,6 +109,7 @@ mc_global_t mc_global =
     {
         .cd_symlinks = TRUE,
         .preallocate_space = FALSE,
+        .file_cloning = FALSE
     }
 
 };

lib/global.h

@@ -220,6 +220,8 @@ typedef struct
         // Preallocate space before file copying
         gboolean preallocate_space;
 
+        // Use COW file cloning on supported filesystems;
+        gboolean file_cloning;
     } vfs;
 } mc_global_t;
 

src/filemanager/boxes.c

@@ -38,6 +38,9 @@
 #include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>  // FICLONE
+#endif
 
 #include "lib/global.h"
 
@@ -569,6 +572,7 @@ configure_box (void)
                     QUICK_CHECKBOX (_ ("Mkdi&r autoname"), &auto_fill_mkdir_name, NULL),
                     QUICK_CHECKBOX (_ ("&Preallocate space"), &mc_global.vfs.preallocate_space,
                                     NULL),
+                    QUICK_CHECKBOX (_ ("Use COW file cloning"), &mc_global.vfs.file_cloning, NULL),
                 QUICK_STOP_GROUPBOX,
                 QUICK_START_GROUPBOX (_ ("Esc key mode")),
                     QUICK_CHECKBOX (_ ("S&ingle press"), &old_esc_mode, &configure_old_esc_mode_id),
@@ -619,17 +623,22 @@ configure_box (void)
         g_snprintf (time_out, sizeof (time_out), "%d", old_esc_mode_timeout);
 
 #ifndef USE_INTERNAL_EDIT
-        quick_widgets[17].state = WST_DISABLED;
+        quick_widgets[18].state = WST_DISABLED;
 #endif
 
         if (!old_esc_mode)
-            quick_widgets[10].state = WST_DISABLED;
+            quick_widgets[11].state = WST_DISABLED;
 
 #ifndef HAVE_POSIX_FALLOCATE
         mc_global.vfs.preallocate_space = FALSE;
         quick_widgets[6].state = WST_DISABLED;
 #endif
 
+#if !defined(FICLONE) && !defined(HAVE_COPY_FILE_RANGE) && !defined(HAVE_SYS_CLONEFILE_H) && !defined(HAVE_REFLINK)
+        mc_global.vfs.file_cloning = FALSE;
+        quick_widgets[7].state = WST_DISABLED;
+#endif
+
         if (quick_dialog (&qdlg) == B_ENTER)
         {
             if (time_out_new[0] == '\0')

src/filemanager/file.c

@@ -2597,7 +2597,7 @@ copy_file_file (file_op_context_t *ctx, const char *src_path, const char *dst_pa
     // On macOS 10.12+ and Solaris 11.4+, the syscalls for file cloning respond for creation of the
     // destination file, so try them before mc_open to avoid handling various races later.
     // Full file cloning is not supported in append and reget modes.
-    if (!(dst_exists && ctx->do_append))
+    if (mc_global.vfs.file_cloning && !(dst_exists && ctx->do_append))
     {
         // Destination file must not exist before the cloning syscall
         if (dst_exists)
@@ -2652,7 +2652,7 @@ copy_file_file (file_op_context_t *ctx, const char *src_path, const char *dst_pa
 
 #if defined(FICLONE) || defined(HAVE_COPY_FILE_RANGE)
     // Try clone the file first. It's not supported in append mode
-    if (!appending && vfs_clone_file (dest_desc, src_desc) == 0)
+    if (mc_global.vfs.file_cloning && !appending && vfs_clone_file (dest_desc, src_desc) == 0)
     {
         dst_status = DEST_FULL;
         return_status = FILE_CONT;

src/setup.c

@@ -365,6 +365,7 @@ static const struct
 #ifdef ENABLE_EXT2FS_ATTR
     { "copymove_persistent_ext2_attr", &copymove_persistent_ext2_attr },
 #endif
+    { "file_cloning", &mc_global.vfs.file_cloning },
     {
         NULL,
         NULL,