implement littlefs for stm32 (#5987)

Co-authored-by: GUVWAF <78759985+GUVWAF@users.noreply.github.com>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Daniel Peter Chokola <dan.chokola@gmail.com>
Co-authored-by: Mark Trevor Birss <markbirss@gmail.com>
Co-authored-by: Austin <vidplace7@gmail.com>

src/platform/stm32wl/STM32_LittleFS_File.h

@@ -0,0 +1,108 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef STM32_LITTLEFS_FILE_H_
+#define STM32_LITTLEFS_FILE_H_
+
+#include "littlefs/lfs.h"
+
+// Forward declaration
+class STM32_LittleFS;
+
+namespace STM32_LittleFS_Namespace
+{
+
+// avoid conflict with other FileSystem FILE_READ/FILE_WRITE
+enum {
+    FILE_O_READ = 0,
+    FILE_O_WRITE = 1,
+};
+
+class File : public Stream
+{
+  public:
+    File(STM32_LittleFS &fs);
+    File(char const *filename, uint8_t mode, STM32_LittleFS &fs);
+
+  public:
+    bool open(char const *filename, uint8_t mode);
+
+    //------------- Stream API -------------//
+    virtual size_t write(uint8_t ch);
+    virtual size_t write(uint8_t const *buf, size_t size);
+    size_t write(const char *str)
+    {
+        if (str == NULL)
+            return 0;
+        return write((const uint8_t *)str, strlen(str));
+    }
+    size_t write(const char *buffer, size_t size) { return write((const uint8_t *)buffer, size); }
+
+    virtual int read(void);
+    int read(void *buf, uint16_t nbyte);
+
+    virtual int peek(void);
+    virtual int available(void);
+    virtual void flush(void);
+
+    bool seek(uint32_t pos);
+    uint32_t position(void);
+    uint32_t size(void);
+
+    bool truncate(uint32_t pos);
+    bool truncate(void);
+
+    void close(void);
+
+    operator bool(void);
+
+    bool isOpen(void);
+    char const *name(void);
+
+    bool isDirectory(void);
+    File openNextFile(uint8_t mode = FILE_O_READ);
+    void rewindDirectory(void);
+
+  private:
+    STM32_LittleFS *_fs;
+
+    bool _is_dir;
+
+    union {
+        lfs_file_t *_file;
+        lfs_dir_t *_dir;
+    };
+
+    char *_dir_path;
+    char _name[LFS_NAME_MAX + 1];
+
+    bool _open(char const *filepath, uint8_t mode);
+    bool _open_file(char const *filepath, uint8_t mode);
+    bool _open_dir(char const *filepath);
+    void _close(void);
+};
+
+} // namespace STM32_LittleFS_Namespace
+
+#endif /* STM32_LITTLEFS_FILE_H_ */