libluna: Use a String for name and handle prefix correctly in TarStream

kernel/src/fs/InitRD.cpp

@@ -37,13 +37,13 @@ Result<void> InitRD::populate_vfs()
     {
         if (entry.type == TarStream::EntryType::RegularFile)
         {
-            auto file = TRY(VFS::create_file(entry.name, Credentials {}));
+            auto file = TRY(VFS::create_file(entry.name.chars(), Credentials {}));
             file->write(entry.data(), 0, entry.size);
             file->chmod(entry.mode & (mode_t)~S_IFMT);
         }
         else if (entry.type == TarStream::EntryType::Directory)
         {
-            TRY(vfs_create_dir_if_not_exists(entry.name, entry.mode));
+            TRY(vfs_create_dir_if_not_exists(entry.name.chars(), entry.mode));
         }
     }
 

libluna/include/luna/TarStream.h

@@ -1,5 +1,6 @@
 #pragma once
 #include <luna/Result.h>
+#include <luna/String.h>
 #include <luna/Types.h>
 #include <sys/types.h>
 
@@ -9,12 +10,13 @@ class TarStream
     enum class EntryType
     {
         RegularFile,
-        Directory
+        Directory,
+        Unimplemented,
     };
 
     struct Entry
     {
-        char name[257];
+        String name;
         usize size;
         mode_t mode;
         EntryType type;

libluna/src/TarStream.cpp

@@ -1,8 +1,8 @@
-#define _LUNA_SYSTEM_ERROR_EXTENSIONS
 #include <luna/Alignment.h>
 #include <luna/Alloc.h>
 #include <luna/CString.h>
 #include <luna/NumberParsing.h>
+#include <luna/StringBuilder.h>
 #include <luna/TarStream.h>
 
 TarStream::TarStream(void* base, usize size) : m_base(base), m_pos(base), m_size(size)
@@ -52,11 +52,19 @@ Result<TarStream::Entry> TarStream::parse_header(const TarStream::TarHeader* hdr
     case '\0':
     case '0': entry.type = EntryType::RegularFile; break;
     case '5': entry.type = EntryType::Directory; break;
-    default: return err(EFIXME);
+    default: entry.type = EntryType::Unimplemented; break;
     }
 
-    if (!strlen(hdr->prefix)) { strlcpy(entry.name, hdr->name, 101); }
-    else { return err(EFIXME); }
+    if (!strlen(hdr->prefix))
+        entry.name = TRY(String::from_string_view(StringView::from_fixed_size_cstring(hdr->name, sizeof(hdr->name))));
+    else
+    {
+        StringBuilder sb;
+        TRY(sb.add(StringView::from_fixed_size_cstring(hdr->prefix, sizeof(hdr->prefix))));
+        TRY(sb.add('/'));
+        TRY(sb.add(StringView::from_fixed_size_cstring(hdr->name, sizeof(hdr->name))));
+        entry.name = TRY(sb.string());
+    }
 
     if (entry.size)
     {