less flushing

src/crypto.h

@@ -1,11 +1,10 @@
 #pragma once
 #include "common.h"
+#include <algorithm>
 #include <botan/aead.h>
 #include <botan/auto_rng.h>
 #include <botan/pwdhash.h>
 
-#include <algorithm>
-
 namespace Crypto {
 
 inline Botan::secure_vector<u8> encrypt(const Botan::secure_vector<u8> &key,
@@ -16,15 +15,16 @@ inline Botan::secure_vector<u8> encrypt(const Botan::secure_vector<u8> &key,
 
   // XChaCha20 is selected automatically based on the nonce size
   // https://github.com/randombit/botan/blob/master/src/lib/stream/chacha/chacha.cpp#L375
-  static auto cipher = Botan::AEAD_Mode::create_or_throw(
+  static thread_local auto cipher = Botan::AEAD_Mode::create_or_throw(
       "ChaCha20Poly1305", Botan::Cipher_Dir::Encryption);
+  cipher->clear();
 
   auto nonce = rng.random_array<24>();
   cipher->set_key(key);
   cipher->start(nonce);
 
   Botan::secure_vector<u8> res;
-  res.resize(24 + plaintext.size() + 16);
+  res.resize(24 + plaintext.size());
   std::ranges::copy(nonce, res.begin());
   std::ranges::copy(plaintext, res.begin() + 24);
   cipher->finish(res, 24);
@@ -40,8 +40,9 @@ decrypt(const Botan::secure_vector<u8> &key,
   std::array<u8, 24> nonce{};
   std::copy_n(ciphertext_with_nonce.begin(), 24, nonce.begin());
 
-  static auto cipher = Botan::AEAD_Mode::create_or_throw(
+  static thread_local auto cipher = Botan::AEAD_Mode::create_or_throw(
       "ChaCha20Poly1305", Botan::Cipher_Dir::Decryption);
+  cipher->clear();
 
   cipher->set_key(key);
   cipher->start(nonce);

src/mainwindow.cc

@@ -70,10 +70,9 @@ MainWindow::MainWindow(QWidget *parent)
     ui->statusbar->showMessage("Creating the vault...");
     QCoreApplication::processEvents();
 
-    Vault::create(path.toStdString(), password.toStdString());
-
     m_vault =
-        std::make_unique<Vault>(path.toStdString(), password.toStdString());
+        Vault::create_and_open(path.toStdString(), password.toStdString());
+
     ui->statusbar->showMessage("Opened " + path);
 
     reload_fs_tree();
@@ -134,6 +133,7 @@ MainWindow::MainWindow(QWidget *parent)
       file.read(content.data(), size);
       m_vault->create_file(basename(path.toStdString()), content);
     }
+    m_vault->flush();
 
     reload_fs_tree();
     ui->statusbar->showMessage("Added " + QString::number(paths.size()) +
@@ -304,6 +304,7 @@ void MainWindow::file_context_menu(const QPoint &pos) {
       style()->standardIcon(QStyle::SP_DialogCancelButton), "Delete");
   connect(delete_action, &QAction::triggered, this, [this, item]() {
     m_vault->delete_file(item->text(0).toStdString());
+    m_vault->flush();
     reload_fs_tree();
   });
 
@@ -346,6 +347,7 @@ void MainWindow::dropEvent(QDropEvent *event) {
     file.read(content.data(), size);
     m_vault->create_file(basename(u.toLocalFile().toStdString()), content);
   }
+  m_vault->flush();
   ui->statusbar->showMessage(
       "Added " + QString::number(event->mimeData()->urls().size()) + " files");
   reload_fs_tree();

src/vault.cc

@@ -49,7 +49,8 @@ Vault::Vault(std::string path, const std::string &password)
   build_file_map();
 }
 
-void Vault::create(const std::string &path, const std::string &password) {
+std::unique_ptr<Vault> Vault::create_and_open(const std::string &path,
+                                              const std::string &password) {
   static Botan::AutoSeeded_RNG rng;
   auto salt = rng.random_array<16>();
 
@@ -64,6 +65,8 @@ void Vault::create(const std::string &path, const std::string &password) {
   WRITE(file, to_char_ptr(salt.data()), 16);
   WRITE(file, to_char_ptr(check_ciphertext.data()), 46);
   file.close();
+
+  return std::make_unique<Vault>(path, password);
 }
 
 void Vault::build_file_map() {
@@ -86,8 +89,8 @@ void Vault::build_file_map() {
   }
 }
 
-std::string Vault::read_file(const std::string &filename) {
-  auto header = m_file_map.at(filename);
+std::string Vault::read_file(const std::string &name) {
+  auto header = m_file_map.at(name);
   ASSERT(!header.deleted);
 
   m_file.clear();
@@ -102,14 +105,15 @@ std::string Vault::read_file(const std::string &filename) {
   return {to_char_ptr(plaintext.data()), plaintext.size()};
 }
 
-void Vault::create_file(const std::string &filename,
-                        const std::string &content) {
+void Vault::create_file(const std::string &name, const std::string &content) {
+  ASSERT(!m_file_map.contains(name));
+
   m_file.clear();
   m_file.seekp(0, std::ios::end);
 
   auto offset = m_file.tellp();
 
-  auto name_ciphertext = Crypto::encrypt(m_key, to_span(filename));
+  auto name_ciphertext = Crypto::encrypt(m_key, to_span(name));
   u64 name_ciphertext_size = name_ciphertext.size();
 
   auto ciphertext = Crypto::encrypt(m_key, to_span(content));
@@ -122,20 +126,19 @@ void Vault::create_file(const std::string &filename,
   WRITE(m_file, &ciphertext_size, sizeof(u64));
   auto content_offset = m_file.tellp();
   WRITE(m_file, ciphertext.data(), ciphertext_size);
-  m_file.flush();
 
-  m_file_map[filename] = FileHeader{
+  m_file_map[name] = FileHeader{
       .offset = static_cast<u64>(offset),
       .deleted = false,
       .name_ciphertext_size = name_ciphertext_size,
-      .name = filename,
+      .name = name,
       .content_ciphertext_size = ciphertext_size,
       .content_offset = static_cast<u64>(content_offset),
   };
 }
 
-void Vault::delete_file(const std::string &filename) {
-  auto header = m_file_map.at(filename);
+void Vault::delete_file(const std::string &name) {
+  auto header = m_file_map.at(name);
 
   // zero the ciphertext and mark as deleted
   m_file.clear();
@@ -152,15 +155,14 @@ void Vault::delete_file(const std::string &filename) {
   m_file.seekp(static_cast<i64>(header.offset), std::ios::beg);
   bool deleted = true;
   WRITE(m_file, &deleted, sizeof(bool));
-  m_file.flush();
 
-  m_file_map.erase(filename);
+  m_file_map.erase(name);
 }
 
-void Vault::update_file(const std::string &filename,
-                        const std::string &content) {
-  delete_file(filename);
-  create_file(filename, content);
+void Vault::update_file(const std::string &name, const std::string &content) {
+  delete_file(name);
+  create_file(name, content);
+  flush();
 }
 
 std::optional<FileHeader> Vault::read_file_header() {

src/vault.h

@@ -3,6 +3,7 @@
 #include "common.h"
 #include <botan/secmem.h>
 #include <fstream>
+#include <memory>
 #include <optional>
 #include <unordered_map>
 
@@ -22,12 +23,14 @@ class Vault {
 public:
   explicit Vault(std::string path, const std::string &password);
 
-  static void create(const std::string &path, const std::string &password);
+  static std::unique_ptr<Vault> create_and_open(const std::string &path,
+                                                const std::string &password);
 
   std::string read_file(const std::string &name);
   void create_file(const std::string &name, const std::string &content);
   void delete_file(const std::string &name);
   void update_file(const std::string &name, const std::string &content);
+  void flush() { m_file.flush(); }
 
   const std::string &path() const { return m_path; }
   const std::unordered_map<std::string, FileHeader> &file_map() const {