File locking and DevelopmentService improvements (#358)

- Moved `file::getlock(path)` from `Tactility` to `TactilityCore`
- Changed all existing `file::*` functions to implement locking by default
- Removed all manual locking where `file::*` functions were used
- When `DevelopmentService` receives a file, it doesn't try to allocate it all in memory. This fixes going out-of-memory on devices without PSRAM.
- Fix for TactilityC include

Tactility/Include/Tactility/file/FileLock.h

@@ -13,20 +13,8 @@ namespace tt::file {
 
 /**
  * @param[in] path the path to find a lock for
- * @return a non-null lock for the specified path.
+ * @return a lock instance when a lock was found, otherwise nullptr
  */
-std::shared_ptr<Lock> getLock(const std::string& path);
-
-/**
- * Acquires a lock, calls the function, then releases the lock.
- * @param[in] path the path to find a lock for
- * @param[in] fn the code to execute while the lock is acquired
- */
-template<typename ReturnType>
-ReturnType withLock(const std::string& path, std::function<ReturnType()> fn) {
-    const auto lock = getLock(path)->asScopedLock();
-    lock.lock();
-    return fn();
-}
+std::shared_ptr<Lock> _Nullable findLock(const std::string& path);
 
 }

Tactility/Include/Tactility/network/HttpdReq.h

@@ -24,6 +24,8 @@ std::map<std::string, std::string> parseContentDisposition(const std::vector<std
 
 bool readAndDiscardOrSendError(httpd_req_t* request, const std::string& toRead);
 
+size_t receiveFile(httpd_req_t* request, size_t length, const std::string& filePath);
+
 }
 
 #endif // ESP_PLATFORM

Tactility/Source/Tactility.cpp

@@ -17,6 +17,7 @@
 
 #include <map>
 #include <format>
+#include <Tactility/file/FileLock.h>
 
 #ifdef ESP_PLATFORM
 #include <Tactility/InitEsp.h>
@@ -188,11 +189,9 @@ static void registerInstalledApps(const std::string& path) {
 static void registerInstalledAppsFromSdCard(const std::shared_ptr<hal::sdcard::SdCardDevice>& sdcard) {
     auto sdcard_root_path = sdcard->getMountPath();
     auto app_path = std::format("{}/app", sdcard_root_path);
-    sdcard->getLock()->lock();
     if (file::isDirectory(app_path)) {
         registerInstalledApps(app_path);
     }
-    sdcard->getLock()->unlock();
 }
 
 static void registerInstalledAppsFromSdCards() {
@@ -269,6 +268,7 @@ void run(const Configuration& config) {
 #ifdef ESP_PLATFORM
     initEsp();
 #endif
+    file::setFindLockFunction(file::findLock);
     settings::initTimeZone();
     hal::init(*config.hardware);
     network::ntp::init();

Tactility/Source/app/AppInstall.cpp

@@ -106,12 +106,9 @@ static bool untar(const std::string& tarPath, const std::string& destinationPath
 }
 
 void cleanupInstallDirectory(const std::string& path) {
-    const auto lock = file::getLock(path);
-    lock->lock();
     if (!file::deleteRecursively(path)) {
         TT_LOG_W(TAG, "Failed to delete existing installation at %s", path.c_str());
     }
-    lock->unlock();
 }
 
 bool install(const std::string& path) {
@@ -121,23 +118,18 @@ bool install(const std::string& path) {
     auto app_parent_path = getAppInstallPath();
     TT_LOG_I(TAG, "Installing app %s to %s", path.c_str(), app_parent_path.c_str());
 
-    auto target_path_lock = file::getLock(app_parent_path)->asScopedLock();
-
-    target_path_lock.lock();
     auto filename = file::getLastPathSegment(path);
     const std::string app_target_path = std::format("{}/{}", app_parent_path, filename);
     if (file::isDirectory(app_target_path) && !file::deleteRecursively(app_target_path)) {
         TT_LOG_W(TAG, "Failed to delete %s", app_target_path.c_str());
     }
-    target_path_lock.unlock();
 
-    target_path_lock.lock();
     if (!file::findOrCreateDirectory(app_target_path, 0777)) {
         TT_LOG_I(TAG, "Failed to create directory %s", app_target_path.c_str());
         return false;
     }
-    target_path_lock.unlock();
 
+    auto target_path_lock = file::getLock(app_parent_path)->asScopedLock();
     auto source_path_lock = file::getLock(path)->asScopedLock();
     target_path_lock.lock();
     source_path_lock.lock();
@@ -149,23 +141,19 @@ bool install(const std::string& path) {
     source_path_lock.unlock();
     target_path_lock.unlock();
 
-    target_path_lock.lock();
     auto manifest_path = app_target_path + "/manifest.properties";
     if (!file::isFile(manifest_path)) {
         TT_LOG_E(TAG, "Manifest not found at %s", manifest_path.c_str());
         cleanupInstallDirectory(app_target_path);
         return false;
     }
-    target_path_lock.unlock();
 
-    target_path_lock.lock();
     std::map<std::string, std::string> properties;
     if (!file::loadPropertiesFile(manifest_path, properties)) {
         TT_LOG_E(TAG, "Failed to load manifest at %s", manifest_path.c_str());
         cleanupInstallDirectory(app_target_path);
         return false;
     }
-    target_path_lock.unlock();
 
     AppManifest manifest;
     if (!parseManifest(properties, manifest)) {
@@ -179,7 +167,6 @@ bool install(const std::string& path) {
         stopAll(manifest.appId);
     }
 
-    target_path_lock.lock();
     const std::string renamed_target_path = std::format("{}/{}", app_parent_path, manifest.appId);
     if (file::isDirectory(renamed_target_path)) {
         if (!file::deleteRecursively(renamed_target_path)) {
@@ -188,15 +175,16 @@ bool install(const std::string& path) {
             return false;
         }
     }
-    target_path_lock.unlock();
 
     target_path_lock.lock();
-    if (rename(app_target_path.c_str(), renamed_target_path.c_str()) != 0) {
+    bool rename_success = rename(app_target_path.c_str(), renamed_target_path.c_str()) == 0;
+    target_path_lock.unlock();
+
+    if (!rename_success) {
         TT_LOG_E(TAG, "Failed to rename \"%s\" to \"%s\"", app_target_path.c_str(), manifest.appId.c_str());
         cleanupInstallDirectory(app_target_path);
         return false;
     }
-    target_path_lock.unlock();
 
     manifest.appLocation = Location::external(renamed_target_path);
 
@@ -214,22 +202,20 @@ bool uninstall(const std::string& appId) {
     }
 
     auto app_path = getAppInstallPath(appId);
-    return file::withLock<bool>(app_path, [&app_path, &appId] {
-        if (!file::isDirectory(app_path)) {
-            TT_LOG_E(TAG, "App %s not found at ", app_path.c_str());
-            return false;
-        }
+    if (!file::isDirectory(app_path)) {
+        TT_LOG_E(TAG, "App %s not found at ", app_path.c_str());
+        return false;
+    }
 
-        if (!file::deleteRecursively(app_path)) {
-            return false;
-        }
+    if (!file::deleteRecursively(app_path)) {
+        return false;
+    }
 
-        if (!removeApp(appId)) {
-            TT_LOG_W(TAG, "Failed to remove app %d from registry", appId.c_str());
-        }
+    if (!removeApp(appId)) {
+        TT_LOG_W(TAG, "Failed to remove app %d from registry", appId.c_str());
+    }
 
-        return true;
-    });
+    return true;
 }
 
 } // namespace

Tactility/Source/app/files/State.cpp

@@ -57,19 +57,17 @@ bool State::setEntriesForPath(const std::string& path) {
         return true;
     } else {
         dir_entries.clear();
-        return file::withLock<bool>(path, [this, &path] {
-            int count = file::scandir(path, dir_entries, &file::direntFilterDotEntries, file::direntSortAlphaAndType);
-            if (count >= 0) {
-                TT_LOG_I(TAG, "%s has %u entries", path.c_str(), count);
-                current_path = path;
-                selected_child_entry = "";
-                action = ActionNone;
-                return true;
-            } else {
-                TT_LOG_E(TAG, "Failed to fetch entries for %s", path.c_str());
-                return false;
-            }
-        });
+        int count = file::scandir(path, dir_entries, &file::direntFilterDotEntries, file::direntSortAlphaAndType);
+        if (count >= 0) {
+            TT_LOG_I(TAG, "%s has %u entries", path.c_str(), count);
+            current_path = path;
+            selected_child_entry = "";
+            action = ActionNone;
+            return true;
+        } else {
+            TT_LOG_E(TAG, "Failed to fetch entries for %s", path.c_str());
+            return false;
+        }
     }
 }
 

Tactility/Source/app/files/View.cpp

@@ -317,17 +317,18 @@ void View::onResult(LaunchId launchId, Result result, std::unique_ptr<Bundle> bu
     switch (state->getPendingAction()) {
         case State::ActionDelete: {
             if (alertdialog::getResultIndex(*bundle) == 0) {
-                file::withLock<void>(filepath, [&filepath] {
-                    if (file::isDirectory(filepath)) {
-                       if (!file::deleteRecursively(filepath)) {
-                           TT_LOG_W(TAG, "Failed to delete %s", filepath.c_str());
-                       }
-                   } else if (file::isFile(filepath)) {
-                       if (remove(filepath.c_str()) <= 0) {
-                           TT_LOG_W(TAG, "Failed to delete %s", filepath.c_str());
-                       }
-                   }
-                });
+                if (file::isDirectory(filepath)) {
+                    if (!file::deleteRecursively(filepath)) {
+                        TT_LOG_W(TAG, "Failed to delete %s", filepath.c_str());
+                    }
+                } else if (file::isFile(filepath)) {
+                    auto lock = file::getLock(filepath);
+                    lock->lock();
+                    if (remove(filepath.c_str()) <= 0) {
+                        TT_LOG_W(TAG, "Failed to delete %s", filepath.c_str());
+                    }
+                    lock->unlock();
+                }
 
                 state->setEntriesForPath(state->getCurrentPath());
                 update();
@@ -337,14 +338,15 @@ void View::onResult(LaunchId launchId, Result result, std::unique_ptr<Bundle> bu
         case State::ActionRename: {
             auto new_name = inputdialog::getResult(*bundle);
             if (!new_name.empty() && new_name != state->getSelectedChildEntry()) {
-                file::withLock<void>(filepath, [this, &filepath, &new_name] {
-                    std::string rename_to = file::getChildPath(state->getCurrentPath(), new_name);
-                   if (rename(filepath.c_str(), rename_to.c_str())) {
-                       TT_LOG_I(TAG, "Renamed \"%s\" to \"%s\"", filepath.c_str(), rename_to.c_str());
-                   } else {
-                       TT_LOG_E(TAG, "Failed to rename \"%s\" to \"%s\"", filepath.c_str(), rename_to.c_str());
-                   }
-                });
+                auto lock = file::getLock(filepath);
+                lock->lock();
+                std::string rename_to = file::getChildPath(state->getCurrentPath(), new_name);
+                if (rename(filepath.c_str(), rename_to.c_str())) {
+                    TT_LOG_I(TAG, "Renamed \"%s\" to \"%s\"", filepath.c_str(), rename_to.c_str());
+                } else {
+                    TT_LOG_E(TAG, "Failed to rename \"%s\" to \"%s\"", filepath.c_str(), rename_to.c_str());
+                }
+                lock->unlock();
 
                 state->setEntriesForPath(state->getCurrentPath());
                 update();

Tactility/Source/app/fileselection/State.cpp

@@ -34,12 +34,6 @@ std::string State::getSelectedChildPath() const {
 }
 
 bool State::setEntriesForPath(const std::string& path) {
-    auto lock = mutex.asScopedLock();
-    if (!lock.lock(100)) {
-        TT_LOG_E(TAG, LOG_MESSAGE_MUTEX_LOCK_FAILED_FMT, "setEntriesForPath");
-        return false;
-    }
-
     TT_LOG_I(TAG, "Changing path: %s -> %s", current_path.c_str(), path.c_str());
 
     /**

Tactility/Source/file/FileLock.cpp

@@ -5,20 +5,8 @@
 
 namespace tt::file {
 
-class NoLock : public Lock {
-    bool lock(TickType_t timeout) const override { return true; }
-    bool unlock() const override { return true; }
-};
-
-static std::shared_ptr<Lock> noLock = std::make_shared<NoLock>();
-
-std::shared_ptr<Lock> getLock(const std::string& path) {
-    auto sdcard_lock = hal::sdcard::findSdCardLock(path);
-    if (sdcard_lock != nullptr) {
-        return sdcard_lock;
-    } else {
-        return noLock;
-    }
+std::shared_ptr<Lock> _Nullable findLock(const std::string& path) {
+    return hal::sdcard::findSdCardLock(path);
 }
 
 }

Tactility/Source/file/PropertiesFile.cpp

@@ -19,28 +19,26 @@ bool getKeyValuePair(const std::string& input, std::string& key, std::string& va
 }
 
 bool loadPropertiesFile(const std::string& filePath, std::function<void(const std::string& key, const std::string& value)> callback) {
-    return file::withLock<bool>(filePath, [&filePath, &callback] {
-        TT_LOG_I(TAG, "Reading properties file %s", filePath.c_str());
-        uint16_t line_count = 0;
-        std::string key_prefix = "";
-        return readLines(filePath, true, [&key_prefix, &line_count, &filePath, &callback](const std::string& line) {
-            line_count++;
-            std::string key, value;
-            auto trimmed_line = string::trim(line, " \t");
-            if (!trimmed_line.starts_with("#")) {
-                if (trimmed_line.starts_with("[")) {
-                    key_prefix = trimmed_line;
-                } else {
-                    if (getKeyValuePair(trimmed_line, key, value)) {
-                       std::string trimmed_key = key_prefix + string::trim(key, " \t");
-                       std::string trimmed_value = string::trim(value, " \t");
-                       callback(trimmed_key, trimmed_value);
-                   } else {
-                       TT_LOG_E(TAG, "Failed to parse line %d of %s", line_count, filePath.c_str());
-                   }
-                }
+    TT_LOG_I(TAG, "Reading properties file %s", filePath.c_str());
+    uint16_t line_count = 0;
+    std::string key_prefix = "";
+    return readLines(filePath, true, [&key_prefix, &line_count, &filePath, &callback](const std::string& line) {
+        line_count++;
+        std::string key, value;
+        auto trimmed_line = string::trim(line, " \t");
+        if (!trimmed_line.starts_with("#")) {
+            if (trimmed_line.starts_with("[")) {
+                key_prefix = trimmed_line;
+            } else {
+                if (getKeyValuePair(trimmed_line, key, value)) {
+                   std::string trimmed_key = key_prefix + string::trim(key, " \t");
+                   std::string trimmed_value = string::trim(value, " \t");
+                   callback(trimmed_key, trimmed_value);
+               } else {
+                   TT_LOG_E(TAG, "Failed to parse line %d of %s", line_count, filePath.c_str());
+               }
             }
-        });
+        }
     });
 }
 

Tactility/Source/i18n/TextResources.cpp

@@ -64,10 +64,8 @@ bool TextResources::load() {
         return false;
     }
 
-    file::withLock<void>(file_path, [&file_path, &new_data] {
-        file::readLines(file_path, true, [&new_data](const char* line) {
-            new_data.push_back(line);
-        });
+    file::readLines(file_path, true, [&new_data](const char* line) {
+        new_data.push_back(line);
     });
 
     if (new_data.empty()) {

Tactility/Source/network/HttpdReq.cpp

@@ -5,6 +5,7 @@
 #include <sstream>
 #include <Tactility/Log.h>
 #include <Tactility/StringUtils.h>
+#include <Tactility/file/File.h>
 
 #ifdef ESP_PLATFORM
 
@@ -161,6 +162,39 @@ bool readAndDiscardOrSendError(httpd_req_t* request, const std::string& toRead)
     return true;
 }
 
+size_t receiveFile(httpd_req_t* request, size_t length, const std::string& filePath) {
+    constexpr auto BUFFER_SIZE = 512;
+    char buffer[BUFFER_SIZE];
+    size_t bytes_received = 0;
+
+    auto lock = file::getLock(filePath)->asScopedLock();
+    lock.lock();
+
+    auto* file = fopen(filePath.c_str(), "wb");
+    if (file == nullptr) {
+        TT_LOG_E(TAG, "Failed to open file for writing: %s", filePath.c_str());
+        return 0;
+    }
+
+    while (bytes_received < length) {
+        auto expected_chunk_size = std::min<size_t>(BUFFER_SIZE, length - bytes_received);
+        size_t receive_chunk_size = httpd_req_recv(request, buffer, expected_chunk_size);
+        if (receive_chunk_size <= 0) {
+            TT_LOG_E(TAG, "Receive failed");
+            break;
+        }
+        if (fwrite(buffer, 1, receive_chunk_size, file) != receive_chunk_size) {
+            TT_LOG_E(TAG, "Failed to write all bytes");
+            break;
+        }
+        bytes_received += receive_chunk_size;
+    }
+
+    // Write file
+    fclose(file);
+    return bytes_received;
+}
+
 }
 
 #endif // ESP_PLATFORM

Tactility/Source/service/development/DevelopmentService.cpp

@@ -243,45 +243,30 @@ esp_err_t DevelopmentService::handleAppInstall(httpd_req_t* request) {
         return ESP_FAIL;
     }
 
-    // Receive file
-    size_t content_read;
-    auto part_after_file = std::format("\r\n--{}--\r\n", boundary);
-    auto file_size = content_left - part_after_file.length();
-    auto buffer = network::receiveByteArray(request, file_size, content_read);
-    if (content_read != file_size) {
-        httpd_resp_send_err(request, HTTPD_400_BAD_REQUEST, "Multipart form error: file data not received");
-        return ESP_FAIL;
-    }
-    content_left -= content_read;
+    // Receive boundary
+    auto boundary_and_newlines_after_file = std::format("\r\n--{}--\r\n", boundary);
+    auto file_size = content_left - boundary_and_newlines_after_file.length();
 
+    // Create tmp directory
     const std::string tmp_path = getTempPath();
-    auto lock = file::getLock(tmp_path)->asScopedLock();
-
-    lock.lock();
     if (!file::findOrCreateDirectory(tmp_path, 0777)) {
         httpd_resp_send_err(request, HTTPD_500_INTERNAL_SERVER_ERROR, "Failed to save file");
         return ESP_FAIL;
     }
-    lock.unlock();
 
-    // Write file
-    lock.lock();
     auto file_path = std::format("{}/{}", tmp_path, filename_entry->second);
-    auto* file = fopen(file_path.c_str(), "wb");
-    auto file_bytes_written = fwrite(buffer.get(), 1, file_size, file);
-    fclose(file);
-    if (file_bytes_written != file_size) {
+    if (network::receiveFile(request, file_size, file_path) != file_size) {
         httpd_resp_send_err(request, HTTPD_500_INTERNAL_SERVER_ERROR, "Failed to save file");
         return ESP_FAIL;
     }
-    lock.unlock();
 
+    content_left -= file_size;
 
     // Read and verify part
-    if (!network::readAndDiscardOrSendError(request, part_after_file)) {
+    if (!network::readAndDiscardOrSendError(request, boundary_and_newlines_after_file)) {
         return ESP_FAIL;
     }
-    content_left -= part_after_file.length();
+    content_left -= boundary_and_newlines_after_file.length();
 
     if (content_left != 0) {
         TT_LOG_W(TAG, "We have more bytes at the end of the request parsing?!");
@@ -292,11 +277,9 @@ esp_err_t DevelopmentService::handleAppInstall(httpd_req_t* request) {
         return ESP_FAIL;
     }
 
-    lock.lock();
-    if (remove(file_path.c_str()) != 0) {
+    if (!file::deleteFile(file_path.c_str())) {
         TT_LOG_W(TAG, "Failed to delete %s", file_path.c_str());
     }
-    lock.unlock();
 
     TT_LOG_I(TAG, "[200] /app/install -> %s", file_path.c_str());
 

Tactility/Source/service/wifi/WifiBootSplashInit.cpp

@@ -82,8 +82,6 @@ static void importWifiAp(const std::string& filePath) {
 static void importWifiApSettings(std::shared_ptr<hal::sdcard::SdCardDevice> sdcard) {
     auto path = file::getChildPath(sdcard->getMountPath(), "settings");
 
-    auto lock = sdcard->getLock()->asScopedLock();
-    lock.lock();
     std::vector<dirent> dirent_list;
     if (file::scandir(path, dirent_list, [](const dirent* entry) {
         switch (entry->d_type) {
@@ -104,7 +102,6 @@ static void importWifiApSettings(std::shared_ptr<hal::sdcard::SdCardDevice> sdca
     }, nullptr) == 0) {
         return;
     }
-    lock.unlock();
 
     if (dirent_list.empty()) {
         TT_LOG_W(TAG, "No AP files found at %s", sdcard->getMountPath().c_str());

Tactility/Source/settings/SystemSettings.cpp

@@ -6,6 +6,7 @@
 #include <Tactility/settings/SystemSettings.h>
 
 #include <format>
+#include <Tactility/file/File.h>
 
 namespace tt::settings {
 
@@ -20,9 +21,7 @@ static bool loadSystemSettingsFromFile(SystemSettings& properties) {
     auto file_path = std::format(FILE_PATH_FORMAT, file::MOUNT_POINT_DATA);
     TT_LOG_I(TAG, "System settings loading from %s", file_path.c_str());
     std::map<std::string, std::string> map;
-    if (!file::withLock<bool>(file_path, [&map, &file_path] {
-        return file::loadPropertiesFile(file_path, map);
-    })) {
+    if (!file::loadPropertiesFile(file_path, map)) {
         TT_LOG_E(TAG, "Failed to load %s", file_path.c_str());
         return false;
     }
@@ -46,9 +45,6 @@ static bool loadSystemSettingsFromFile(SystemSettings& properties) {
 }
 
 bool loadSystemSettings(SystemSettings& properties) {
-    auto scoped_lock = mutex.asScopedLock();
-    scoped_lock.lock();
-
     if (!cached) {
         if (!loadSystemSettingsFromFile(cachedSettings)) {
             return false;
@@ -61,24 +57,19 @@ bool loadSystemSettings(SystemSettings& properties) {
 }
 
 bool saveSystemSettings(const SystemSettings& properties) {
-    auto scoped_lock = mutex.asScopedLock();
-    scoped_lock.lock();
-
     auto file_path = std::format(FILE_PATH_FORMAT, file::MOUNT_POINT_DATA);
-    return file::withLock<bool>(file_path, [&properties, &file_path] {
-        std::map<std::string, std::string> map;
-        map["language"] = toString(properties.language);
-        map["timeFormat24h"] = properties.timeFormat24h ? "true" : "false";
+    std::map<std::string, std::string> map;
+    map["language"] = toString(properties.language);
+    map["timeFormat24h"] = properties.timeFormat24h ? "true" : "false";
 
-        if (!file::savePropertiesFile(file_path, map)) {
-            TT_LOG_E(TAG, "Failed to save %s", file_path.c_str());
-            return false;
-        }
+    if (!file::savePropertiesFile(file_path, map)) {
+        TT_LOG_E(TAG, "Failed to save %s", file_path.c_str());
+        return false;
+    }
 
-        cachedSettings = properties;
-        cached = true;
-        return true;
-    });
+    cachedSettings = properties;
+    cached = true;
+    return true;
 }
 
 }

TactilityC/Include/tt_app.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <cstdio>
+#include <stdio.h>
 
 #include "tt_app_manifest.h"
 

TactilityC/Source/tt_file.cpp

@@ -1,6 +1,6 @@
 #include <tt_file.h>
 #include <tt_lock_private.h>
-#include <Tactility/file/FileLock.h>
+#include <Tactility/file/File.h>
 
 extern "C" {
 

TactilityCore/Include/Tactility/file/File.h

@@ -1,3 +1,7 @@
+/**
+ * All functions in this file can be safely called without manually applying file locks.
+ * For calls to C stdlib APIs such as fopen(), always call file::getLock(path) first!
+ */
 #pragma once
 
 #include "Tactility/TactilityCore.h"
@@ -40,6 +44,28 @@ struct FileCloser {
     }
 };
 
+typedef std::function<std::shared_ptr<Lock>(const std::string&)> FindLockFunction;
+
+/**
+ * @param[in] path the path to get a lock for
+ * @return a lock instance (never null)
+ */
+std::shared_ptr<Lock> getLock(const std::string& path);
+
+void setFindLockFunction(const FindLockFunction& function);
+
+/**
+ * Acquires a lock, calls the function, then releases the lock.
+ * @param[in] path the path to find a lock for
+ * @param[in] fn the code to execute while the lock is acquired
+ */
+template<typename ReturnType>
+ReturnType withLock(const std::string& path, std::function<ReturnType()> fn) {
+    const auto lock = getLock(path)->asScopedLock();
+    lock.lock();
+    return fn();
+}
+
 long getSize(FILE* file);
 
 /** Read a file and return its data.
@@ -73,6 +99,10 @@ bool findOrCreateParentDirectory(const std::string& path, mode_t mode);
 
 bool deleteRecursively(const std::string& path);
 
+bool deleteFile(const std::string& path);
+
+bool deleteDirectory(const std::string& path);
+
 /**
  * Concatenate a child path with a parent path, ensuring proper slash inbetween
  * @param basePath an absolute path with or without trailing "/"

TactilityCore/Source/file/File.cpp

@@ -11,7 +11,33 @@ class SdCardDevice;
 
 namespace tt::file {
 
-#define TAG "file"
+constexpr auto* TAG = "file";
+
+class NoLock final : public Lock {
+    bool lock(TickType_t timeout) const override { return true; }
+    bool unlock() const override { return true; }
+};
+
+static std::shared_ptr<Lock> noLock = std::make_shared<NoLock>();
+static std::function<std::shared_ptr<Lock>(const std::string&)> findLockFunction = nullptr;
+
+std::shared_ptr<Lock> getLock(const std::string& path) {
+    if (findLockFunction == nullptr) {
+        TT_LOG_W(TAG, "File lock function not set!");
+        return noLock;
+    }
+
+    auto lock = findLockFunction(path);
+    if (lock == nullptr) {
+        return noLock;
+    }
+
+    return lock;
+}
+
+void setFindLockFunction(const FindLockFunction& function) {
+    findLockFunction = function;
+}
 
 std::string getChildPath(const std::string& basePath, const std::string& childPath) {
     // Postfix with "/" when the current path isn't "/"
@@ -40,6 +66,9 @@ bool listDirectory(
     const std::string& path,
     std::function<void(const dirent&)> onEntry
 ) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
+
     TT_LOG_I(TAG, "listDir start %s", path.c_str());
     DIR* dir = opendir(path.c_str());
     if (dir == nullptr) {
@@ -64,6 +93,9 @@ int scandir(
     ScandirFilter _Nullable filterMethod,
     ScandirSort _Nullable sortMethod
 ) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
+
     TT_LOG_I(TAG, "scandir start");
     DIR* dir = opendir(path.c_str());
     if (dir == nullptr) {
@@ -187,6 +219,9 @@ bool writeString(const std::string& filepath, const std::string& content) {
 }
 
 static bool findOrCreateDirectoryInternal(std::string path, mode_t mode) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
+
     struct stat dir_stat;
     if (mkdir(path.c_str(), mode) == 0) {
         return true;
@@ -277,6 +312,7 @@ bool deleteRecursively(const std::string& path) {
             TT_LOG_E(TAG, "Failed to scan directory %s", path.c_str());
             return false;
         }
+
         for (const auto& entry : entries) {
             auto child_path = path + "/" + entry.d_name;
             if (!deleteRecursively(child_path)) {
@@ -284,10 +320,10 @@ bool deleteRecursively(const std::string& path) {
             }
         }
         TT_LOG_I(TAG, "Deleting %s", path.c_str());
-        return rmdir(path.c_str()) == 0;
+        return deleteDirectory(path);
     } else if (isFile(path)) {
         TT_LOG_I(TAG, "Deleting %s", path.c_str());
-        return remove(path.c_str()) == 0;
+        return deleteFile(path);
     } else if (path == "/" || path == "." || path == "..") {
         // No-op
         return true;
@@ -297,17 +333,36 @@ bool deleteRecursively(const std::string& path) {
     }
 }
 
+bool deleteFile(const std::string& path) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
+    return remove(path.c_str()) == 0;
+}
+
+bool deleteDirectory(const std::string& path) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
+    return rmdir(path.c_str()) == 0;
+}
+
 bool isFile(const std::string& path) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
     return access(path.c_str(), F_OK) == 0;
 }
 
 bool isDirectory(const std::string& path) {
+    auto lock = getLock(path)->asScopedLock();
+    lock.lock();
     struct stat stat_result;
     return stat(path.c_str(), &stat_result) == 0 && S_ISDIR(stat_result.st_mode);
 }
 
-bool readLines(const std::string& filepath, bool stripNewLine, std::function<void(const char* line)> callback) {
-    auto* file = fopen(filepath.c_str(), "r");
+bool readLines(const std::string& filePath, bool stripNewLine, std::function<void(const char* line)> callback) {
+    auto lock = getLock(filePath)->asScopedLock();
+    lock.lock();
+
+    auto* file = fopen(filePath.c_str(), "r");
     if (file == nullptr) {
         return false;
     }