Files
crosspoint-reader-mod/lib/hal/HalStorage.h
Xuan-Son Nguyen 6ff5fcd9a7 fix: make file system operations thread-safe (HalFile) (#1212)
## Summary

Fix https://github.com/crosspoint-reader/crosspoint-reader/issues/1137

Introducing `HalFile`, a thin wrapper around `FsFile` that uses a global
mutex to protect file operations.

To test this PR, place the code below somewhere in the code base (I
placed it in `onGoToRecentBooks`)

```cpp
static auto testTask = [](void* param) {
  for (int i = 0; i < 10; i++) {
    String json = Storage.readFile("/.crosspoint/settings.json");
    LOG_DBG("TEST_TASK", "Read settings.json, bytes read: %u", json.length());
  }
  vTaskDelete(nullptr);
};
xTaskCreate(testTask, "test0", 8192, nullptr, 1, nullptr);
xTaskCreate(testTask, "test1", 8192, nullptr, 1, nullptr);
xTaskCreate(testTask, "test2", 8192, nullptr, 1, nullptr);
xTaskCreate(testTask, "test3", 8192, nullptr, 1, nullptr);
delay(1000);
```

It will reliably lead to crash on `master`, but will function correctly
with this PR.

A macro renaming trick is used to avoid changing too many downstream
code files.

---

### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? **PARTIALLY**, only to
help with tedious copy-paste tasks

---------

Co-authored-by: Zach Nelson <zach@zdnelson.com>
2026-02-28 11:15:27 +01:00

108 lines
3.5 KiB
C++

#pragma once
#include <Print.h>
#include <common/FsApiConstants.h> // for oflag_t
#include <freertos/semphr.h>
#include <memory>
#include <string>
#include <vector>
class HalFile;
class HalStorage {
public:
HalStorage();
bool begin();
bool ready() const;
std::vector<String> listFiles(const char* path = "/", int maxFiles = 200);
// Read the entire file at `path` into a String. Returns empty string on failure.
String readFile(const char* path);
// Low-memory helpers:
// Stream the file contents to a `Print` (e.g. `Serial`, or any `Print`-derived object).
// Returns true on success, false on failure.
bool readFileToStream(const char* path, Print& out, size_t chunkSize = 256);
// Read up to `bufferSize-1` bytes into `buffer`, null-terminating it. Returns bytes read.
size_t readFileToBuffer(const char* path, char* buffer, size_t bufferSize, size_t maxBytes = 0);
// Write a string to `path` on the SD card. Overwrites existing file.
// Returns true on success.
bool writeFile(const char* path, const String& content);
// Ensure a directory exists, creating it if necessary. Returns true on success.
bool ensureDirectoryExists(const char* path);
HalFile open(const char* path, const oflag_t oflag = O_RDONLY);
bool mkdir(const char* path, const bool pFlag = true);
bool exists(const char* path);
bool remove(const char* path);
bool rename(const char* oldPath, const char* newPath);
bool rmdir(const char* path);
bool openFileForRead(const char* moduleName, const char* path, HalFile& file);
bool openFileForRead(const char* moduleName, const std::string& path, HalFile& file);
bool openFileForRead(const char* moduleName, const String& path, HalFile& file);
bool openFileForWrite(const char* moduleName, const char* path, HalFile& file);
bool openFileForWrite(const char* moduleName, const std::string& path, HalFile& file);
bool openFileForWrite(const char* moduleName, const String& path, HalFile& file);
bool removeDir(const char* path);
static HalStorage& getInstance() { return instance; }
class StorageLock; // private class, used internally
private:
static HalStorage instance;
bool initialized = false;
SemaphoreHandle_t storageMutex = nullptr;
};
#define Storage HalStorage::getInstance()
class HalFile : public Print {
friend class HalStorage;
class Impl;
std::unique_ptr<Impl> impl;
explicit HalFile(std::unique_ptr<Impl> impl);
public:
HalFile();
~HalFile();
HalFile(HalFile&&);
HalFile& operator=(HalFile&&);
HalFile(const HalFile&) = delete;
HalFile& operator=(const HalFile&) = delete;
void flush();
size_t getName(char* name, size_t len);
size_t size();
size_t fileSize();
bool seek(size_t pos);
bool seekCur(int64_t offset);
bool seekSet(size_t offset);
int available() const;
size_t position() const;
int read(void* buf, size_t count);
int read(); // read a single byte
size_t write(const void* buf, size_t count);
size_t write(uint8_t b) override;
bool rename(const char* newPath);
bool isDirectory() const;
void rewindDirectory();
bool close();
HalFile openNextFile();
bool isOpen() const;
operator bool() const;
};
// Only do renaming FsFile to HalFile if this header is included by downstream code
// The renaming is to allow using the thread-safe HalFile instead of the raw FsFile, without needing to change the
// downstream code
#ifndef HAL_STORAGE_IMPL
using FsFile = HalFile;
#endif
// Downstream code must use Storage instead of SdMan
#ifdef SdMan
#undef SdMan
#endif