ladybird/Kernel/FileSystem/Custody.cpp
2021-07-11 00:51:38 +02:00

91 lines
2.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/StringBuilder.h>
#include <AK/StringView.h>
#include <AK/Vector.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/Inode.h>
namespace Kernel {
KResultOr<NonnullRefPtr<Custody>> Custody::try_create(Custody* parent, StringView name, Inode& inode, int mount_flags)
{
auto name_kstring = KString::try_create(name);
if (!name_kstring)
return ENOMEM;
auto custody = adopt_ref_if_nonnull(new (nothrow) Custody(parent, name_kstring.release_nonnull(), inode, mount_flags));
if (!custody)
return ENOMEM;
return custody.release_nonnull();
}
Custody::Custody(Custody* parent, NonnullOwnPtr<KString> name, Inode& inode, int mount_flags)
: m_parent(parent)
, m_name(move(name))
, m_inode(inode)
, m_mount_flags(mount_flags)
{
}
Custody::~Custody()
{
}
OwnPtr<KString> Custody::try_create_absolute_path() const
{
if (!parent())
return KString::try_create("/"sv);
Vector<Custody const*, 32> custody_chain;
size_t path_length = 0;
for (auto* custody = this; custody; custody = custody->parent()) {
custody_chain.append(custody);
path_length += custody->m_name->length() + 1;
}
VERIFY(path_length > 0);
char* buffer;
auto string = KString::try_create_uninitialized(path_length - 1, buffer);
if (!string)
return string;
size_t string_index = 0;
for (size_t custody_index = custody_chain.size() - 1; custody_index > 0; --custody_index) {
buffer[string_index] = '/';
++string_index;
auto& custody_name = *custody_chain[custody_index - 1]->m_name;
__builtin_memcpy(buffer + string_index, custody_name.characters(), custody_name.length());
string_index += custody_name.length();
}
VERIFY(string->length() == string_index);
buffer[string_index] = 0;
return string;
}
String Custody::absolute_path() const
{
if (!parent())
return "/";
Vector<Custody const*, 32> custody_chain;
for (auto* custody = this; custody; custody = custody->parent())
custody_chain.append(custody);
StringBuilder builder;
for (int i = custody_chain.size() - 2; i >= 0; --i) {
builder.append('/');
builder.append(custody_chain[i]->name());
}
return builder.to_string();
}
bool Custody::is_readonly() const
{
if (m_mount_flags & MS_RDONLY)
return true;
return m_inode->fs().is_readonly();
}
}