AK: Make MappedFile heap-allocated and ref-counted

Let's adapt this class a bit better to how it's actually being used.

Instead of having valid/invalid states and storing an error in case
it's invalid, a MappedFile is now always valid, and the factory
function that creates it will return an OSError if mapping fails.

1 files changed, 5 insertions, 3 deletions

diff --git a/Userland/disasm.cpp b/Userland/disasm.cpp
index 4189499000..781caf0796 100644
--- a/Userland/disasm.cpp
+++ b/Userland/disasm.cpp
@@ -48,12 +48,14 @@ int main(int argc, char** argv)
     args_parser.add_positional_argument(path, "Path to i386 binary file", "path");
     args_parser.parse(argc, argv);
 
-    MappedFile file(path);
-    if (!file.is_valid()) {
-        // Already printed some error message.
+    auto file_or_error = MappedFile::map(path);
+    if (file_or_error.is_error()) {
+        warnln("Could not map file: {}", file_or_error.error().string());
         return 1;
     }
 
+    auto& file = *file_or_error.value();
+
     struct Symbol {
         size_t value;
         size_t size;