User folders: save games and Settings.cfg in Documents\Sacred

The game's ANSI file API calls are hooked; paths under save\ and
Settings.cfg are redirected to Documents\Sacred\save and
Documents\Sacred\config, copied there once from the game folder.
The shared chest uses the same save folder.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/mods/sharedchest.cpp

@@ -12,7 +12,7 @@
 // serializer (vf1c(stream, 1, 0)); loadHero recreates them with
 // cObjectManager::Create(type, 0, 0, 0), vf1c(stream, 0, file version) and
 // gives them their new id. The shared chest does the same into
-// save\shared_chest.json: written whenever a hero is saved, read at the start
+// shared_chest.json in the save folder (mods/userfolders.cpp): written whenever a hero is saved, read at the start
 // of each game session; cleared when the session ends (the ids die with the
 // object manager).
 
@@ -38,7 +38,7 @@
 #include "mods/itemstack.h"
 #include "mods/sharedchest.h"
 #include "mods/skillslots.h"
-#include "re/config.h"
+#include "mods/userfolders.h"
 #include "re/hook.h"
 #include "re/log.h"
 
@@ -102,11 +102,7 @@ bool SharedOpen() {
 }
 
 std::string FilePath() {
-    std::string dir = re::ConfigString("paths", "GameDir", "");
-    if (!dir.empty() && dir.back() != '\\' && dir.back() != '/') {
-        dir += '\\';
-    }
-    return dir + "save\\shared_chest.json";
+    return mods::userfolders::SaveDir() + "shared_chest.json";
 }
 
 // --- items <-> JSON ------------------------------------------------------------

src/mods/sharedchest.h

@@ -2,7 +2,7 @@
 
 namespace mods::sharedchest {
 
-// Writes the shared chest (save\shared_chest.json); called after a hero is saved.
+// Writes the shared chest (shared_chest.json in the save folder); called after a hero is saved.
 void Save();
 
 } // namespace mods::sharedchest

src/mods/userfolders.cpp

@@ -0,0 +1,264 @@
+// User folders (request of 2026-10-19): save games and the game's settings
+// live in the user's Documents instead of the game folder:
+//   Documents\Sacred\save\     GAMEnn.PAK, Heronn.pax, shared_chest.json
+//   Documents\Sacred\config\   Settings.cfg
+//
+// Measured: sacred.exe names these files with paths relative to the game
+// folder (the working directory), from 37 code sites: "./SAVE/GAME%.2d.PAK",
+// "SAVE/GAME%.2d.PAK", "./SAVE/GAMEF%d.PAK", "./SAVE/SAVE02.PAK",
+// "Save\Hero%.2d.pax", ".\Save", "Save", "SAVE\" and "Settings.cfg"
+// (0x95c4ec..0x95d5f4, 0x9e15a0, 0xa18dc4). It reaches files only through
+// kernel32's ANSI file functions, so those are hooked: a path whose first
+// component is "save", or which is "Settings.cfg", is rewritten into the user
+// folder; every other path passes unchanged. One choke point instead of 37
+// patched operands, and no long absolute path in the game's fixed buffers.
+//
+// Migration: the first time a folder is used and does not exist yet, the game
+// folder's files are copied into it (the originals stay where they were).
+// Config.exe and gameserver.exe are separate programs and still use the game
+// folder.
+
+#include "mods/userfolders.h"
+
+#include <string>
+#include <string_view>
+
+#include <windows.h>
+#include <shlobj.h>
+
+#include "re/hook.h"
+#include "re/log.h"
+
+namespace mods::userfolders {
+namespace {
+
+constexpr char kSaveFolder[] = "save";
+constexpr char kSettingsFile[] = "Settings.cfg";
+constexpr wchar_t kUserFolder[] = L"Sacred";
+constexpr wchar_t kUserSaveFolder[] = L"save";
+constexpr wchar_t kUserConfigFolder[] = L"config";
+
+bool IsSeparator(char c) {
+    return c == '\\' || c == '/';
+}
+
+bool EqualsNoCase(std::string_view a, std::string_view b) {
+    return a.size() == b.size() && _strnicmp(a.data(), b.data(), a.size()) == 0;
+}
+
+// The game folder (sacred.exe's), with trailing separator.
+const std::string& GameDir() {
+    static const std::string dir = [] {
+        char path[MAX_PATH];
+        DWORD length = GetModuleFileNameA(nullptr, path, MAX_PATH);
+        std::string result(path, length);
+        return result.substr(0, result.find_last_of("\\/") + 1);
+    }();
+    return dir;
+}
+
+std::wstring Widen(const std::string& text) {
+    std::wstring result(MultiByteToWideChar(CP_ACP, 0, text.c_str(), -1, nullptr, 0), L'\0');
+    MultiByteToWideChar(CP_ACP, 0, text.c_str(), -1, result.data(), static_cast<int>(result.size()));
+    result.pop_back();
+    return result;
+}
+
+// `path` in the game's code page; empty when a character has no ANSI form.
+std::string Narrow(const std::wstring& path) {
+    char buffer[MAX_PATH];
+    BOOL lossy = FALSE;
+    int length = WideCharToMultiByte(CP_ACP, WC_NO_BEST_FIT_CHARS, path.c_str(), -1, buffer, MAX_PATH, nullptr,
+                                     &lossy);
+    return length > 0 && !lossy ? std::string(buffer) : std::string();
+}
+
+bool Exists(const std::wstring& path) {
+    return GetFileAttributesW(path.c_str()) != INVALID_FILE_ATTRIBUTES;
+}
+
+// Copies the files of `from` into `to` (not recursive; the save folder is flat).
+void CopyFiles(const std::wstring& from, const std::wstring& to) {
+    WIN32_FIND_DATAW found;
+    HANDLE find = FindFirstFileW((from + L"\\*").c_str(), &found);
+    if (find == INVALID_HANDLE_VALUE) {
+        return;
+    }
+    int copied = 0;
+    do {
+        if (!(found.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) &&
+            CopyFileW((from + L"\\" + found.cFileName).c_str(), (to + L"\\" + found.cFileName).c_str(), TRUE)) {
+            ++copied;
+        }
+    } while (FindNextFileW(find, &found));
+    FindClose(find);
+    re::Log("user folders: copied %d files from the game's save folder", copied);
+}
+
+// The user folders without trailing separator, in the game's code page; both
+// empty when the Documents folder can't be used (the game folder stays).
+struct Folders {
+    std::string save;
+    std::string config;
+};
+
+// Wide file functions only: the hooked ANSI ones would map the game folder's
+// files onto themselves.
+Folders FindFolders() {
+    PWSTR documents = nullptr;
+    HRESULT result = SHGetKnownFolderPath(FOLDERID_Documents, 0, nullptr, &documents);
+    std::wstring root = SUCCEEDED(result) ? std::wstring(documents) + L"\\" + kUserFolder : std::wstring();
+    CoTaskMemFree(documents);
+
+    Folders folders;
+    if (root.empty() || Narrow(root).empty()) {
+        re::Log("user folders: Documents folder unusable (0x%08lx), files stay in the game folder", result);
+        return folders;
+    }
+    const std::wstring save = root + L"\\" + kUserSaveFolder;
+    const std::wstring config = root + L"\\" + kUserConfigFolder;
+    const std::wstring gameDir = Widen(GameDir());
+    CreateDirectoryW(root.c_str(), nullptr);
+    if (!Exists(save)) {
+        CreateDirectoryW(save.c_str(), nullptr);
+        CopyFiles(gameDir + Widen(kSaveFolder), save);
+    }
+    if (!Exists(config)) {
+        CreateDirectoryW(config.c_str(), nullptr);
+        if (CopyFileW((gameDir + Widen(kSettingsFile)).c_str(), (config + L"\\" + Widen(kSettingsFile)).c_str(),
+                      TRUE)) {
+            re::Log("user folders: copied the game's %s", kSettingsFile);
+        }
+    }
+    folders.save = Narrow(save);
+    folders.config = Narrow(config);
+    re::Log("user folders: save games in %s, settings in %s", folders.save.c_str(), folders.config.c_str());
+    return folders;
+}
+
+// Looked up on first use, not at startup: the hooks are installed under the
+// loader lock, where the shell's folder lookup must not run.
+const Folders& UserFolders() {
+    static const Folders folders = FindFolders();
+    return folders;
+}
+
+// `path` as the game means it, redirected into the user folders; nullptr when
+// it stays as it is. `buffer` holds the result.
+const char* Redirect(const char* path, std::string& buffer) {
+    if (!path) {
+        return nullptr;
+    }
+    std::string_view rest(path);
+    const std::string& gameDir = GameDir();
+    if (rest.size() >= gameDir.size() && EqualsNoCase(rest.substr(0, gameDir.size()), gameDir)) {
+        rest.remove_prefix(gameDir.size());
+    } else if ((rest.size() >= 2 && rest[1] == ':') || (!rest.empty() && IsSeparator(rest[0]))) {
+        return nullptr;   // absolute, elsewhere
+    }
+    while (rest.size() >= 2 && rest[0] == '.' && IsSeparator(rest[1])) {
+        rest.remove_prefix(2);
+    }
+    const size_t end = rest.find_first_of("\\/");
+    const std::string_view first = rest.substr(0, end);
+    const bool save = EqualsNoCase(first, kSaveFolder);
+    if (!save && !(end == std::string_view::npos && EqualsNoCase(first, kSettingsFile))) {
+        return nullptr;
+    }
+    const Folders& folders = UserFolders();
+    if (folders.save.empty()) {
+        return nullptr;
+    }
+    if (save) {
+        buffer = folders.save;
+        for (char c : rest.substr(first.size())) {
+            buffer += c == '/' ? '\\' : c;
+        }
+    } else {
+        buffer = folders.config + "\\" + kSettingsFile;
+    }
+    return buffer.c_str();
+}
+
+// The path to hand to the original function.
+const char* Mapped(const char* path, std::string& buffer) {
+    const char* redirected = Redirect(path, buffer);
+    return redirected ? redirected : path;
+}
+
+} // namespace
+
+std::string SaveDir() {
+    const Folders& folders = UserFolders();
+    return (folders.save.empty() ? GameDir() + kSaveFolder : folders.save) + "\\";
+}
+
+} // namespace mods::userfolders
+
+namespace {
+
+using mods::userfolders::Mapped;
+
+HANDLE WINAPI CreateFileInUserFolders(LPCSTR path, DWORD access, DWORD share, LPSECURITY_ATTRIBUTES security,
+                                      DWORD disposition, DWORD flags, HANDLE templateFile);
+BOOL WINAPI DeleteFileInUserFolders(LPCSTR path);
+HANDLE WINAPI FindFirstFileInUserFolders(LPCSTR pattern, LPWIN32_FIND_DATAA found);
+DWORD WINAPI GetFileAttributesInUserFolders(LPCSTR path);
+BOOL WINAPI GetFileAttributesExInUserFolders(LPCSTR path, GET_FILEEX_INFO_LEVELS level, LPVOID info);
+BOOL WINAPI SetFileAttributesInUserFolders(LPCSTR path, DWORD attributes);
+BOOL WINAPI CreateDirectoryInUserFolders(LPCSTR path, LPSECURITY_ATTRIBUTES security);
+BOOL WINAPI CopyFileInUserFolders(LPCSTR from, LPCSTR to, BOOL failIfExists);
+
+RE_HOOK_API(CreateFileA, CreateFileInUserFolders);
+RE_HOOK_API(DeleteFileA, DeleteFileInUserFolders);
+RE_HOOK_API(FindFirstFileA, FindFirstFileInUserFolders);
+RE_HOOK_API(GetFileAttributesA, GetFileAttributesInUserFolders);
+RE_HOOK_API(GetFileAttributesExA, GetFileAttributesExInUserFolders);
+RE_HOOK_API(SetFileAttributesA, SetFileAttributesInUserFolders);
+RE_HOOK_API(CreateDirectoryA, CreateDirectoryInUserFolders);
+RE_HOOK_API(CopyFileA, CopyFileInUserFolders);
+
+HANDLE WINAPI CreateFileInUserFolders(LPCSTR path, DWORD access, DWORD share, LPSECURITY_ATTRIBUTES security,
+                                      DWORD disposition, DWORD flags, HANDLE templateFile) {
+    std::string buffer;
+    return CreateFileInUserFolders_original(Mapped(path, buffer), access, share, security, disposition, flags,
+                                            templateFile);
+}
+
+BOOL WINAPI DeleteFileInUserFolders(LPCSTR path) {
+    std::string buffer;
+    return DeleteFileInUserFolders_original(Mapped(path, buffer));
+}
+
+HANDLE WINAPI FindFirstFileInUserFolders(LPCSTR pattern, LPWIN32_FIND_DATAA found) {
+    std::string buffer;
+    return FindFirstFileInUserFolders_original(Mapped(pattern, buffer), found);
+}
+
+DWORD WINAPI GetFileAttributesInUserFolders(LPCSTR path) {
+    std::string buffer;
+    return GetFileAttributesInUserFolders_original(Mapped(path, buffer));
+}
+
+BOOL WINAPI GetFileAttributesExInUserFolders(LPCSTR path, GET_FILEEX_INFO_LEVELS level, LPVOID info) {
+    std::string buffer;
+    return GetFileAttributesExInUserFolders_original(Mapped(path, buffer), level, info);
+}
+
+BOOL WINAPI SetFileAttributesInUserFolders(LPCSTR path, DWORD attributes) {
+    std::string buffer;
+    return SetFileAttributesInUserFolders_original(Mapped(path, buffer), attributes);
+}
+
+BOOL WINAPI CreateDirectoryInUserFolders(LPCSTR path, LPSECURITY_ATTRIBUTES security) {
+    std::string buffer;
+    return CreateDirectoryInUserFolders_original(Mapped(path, buffer), security);
+}
+
+BOOL WINAPI CopyFileInUserFolders(LPCSTR from, LPCSTR to, BOOL failIfExists) {
+    std::string fromBuffer;
+    std::string toBuffer;
+    return CopyFileInUserFolders_original(Mapped(from, fromBuffer), Mapped(to, toBuffer), failIfExists);
+}
+
+} // namespace

src/mods/userfolders.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <string>
+
+namespace mods::userfolders {
+
+// Folder of the save games, with trailing separator: Documents\Sacred\save\,
+// or the game's own save\ when the Documents folder is unusable.
+std::string SaveDir();
+
+} // namespace mods::userfolders