Refactor the file size and tell operations

This was done in order to avoid C++ compiler warnings about comparing types with
different signedness.

1 files changed, 6 insertions, 4 deletions

diff --git a/src/backup.c b/src/backup.c
index 4c9dfbd..0b558b6 100644
--- a/src/backup.c
+++ b/src/backup.c
@@ -43,16 +43,18 @@ static int
 check_files(const options_backup_t *const opts,
             const resources_backup_t *const res)
 {
-    const long in_size = file_size(res->in_file);
+    bool in_size_ok = false;
+    const size_t in_size = file_size(res->in_file, &in_size_ok);
 
-    if (in_size < 0) {
+    if (!in_size_ok) {
         print_error("cannot get size of input file: %s", strerror(errno));
         return 1;
     }
 
-    const long ref_size = file_size(res->ref_file);
+    bool ref_size_ok = false;
+    const size_t ref_size = file_size(res->ref_file, &ref_size_ok);
 
-    if (ref_size < 0) {
+    if (!ref_size_ok) {
         print_error("cannot get size of reference file: %s", strerror(errno));
         return 1;
     }