finish copy files follow bytes sort

test/files_save.py

@@ -0,0 +1,72 @@
+import os
+
+
+def extract_drive_letter(path: str) -> str:
+    """从绝对路径中提取盘符"""
+    drive = os.path.splitdrive(path)[0]
+    if not drive:
+        raise ValueError(f"无法从路径中提取盘符：{path}")
+    return drive[0].upper()  # 返回 'Y'
+
+
+def CopyFileFromBytes(source_data_dict, target_path):
+    """
+    根据起始字节和长度，从磁盘中读取数据并保存为目标文件
+
+    :param source_data_dict: 包含源数据信息的字典
+    :param target_path: 目标文件夹路径
+    """
+    start_byte = source_data_dict.get("start_byte")
+    byte_length = source_data_dict.get("length")
+    absolute_path = source_data_dict.get("absolute_path")
+    file_name = source_data_dict.get("filename")
+
+    if byte_length <= 0:
+        print("错误：字节长度无效")
+        return
+
+    if not absolute_path or not file_name:
+        print("错误：缺少必要的文件信息")
+        return
+
+    source_disk_path = extract_drive_letter(absolute_path)
+    target_file_path = os.path.join(target_path, file_name)
+
+    try:
+        # 创建目标目录（如果不存在）
+        os.makedirs(target_path, exist_ok=True)
+
+        with open(fr"\\.\{source_disk_path}:", 'rb') as disk:
+            disk.seek(start_byte)
+
+            with open(target_file_path, 'wb') as f:
+                remaining = byte_length
+                CHUNK_SIZE = 1024 * 1024  # 1MB
+                while remaining > 0:
+                    read_size = min(CHUNK_SIZE, remaining)
+                    chunk = disk.read(read_size)
+                    if not chunk:
+                        print("警告：读取到空数据，可能已到达磁盘末尾。")
+                        break
+                    f.write(chunk)
+                    remaining -= len(chunk)
+
+        print(
+            f"成功：已从字节偏移量 {start_byte} 读取 {byte_length} 字节，保存为 {target_file_path}")
+
+    except PermissionError:
+        print("错误：需要管理员权限访问磁盘设备，请以管理员身份运行此程序")
+    except Exception as e:
+        print(f"发生错误: {str(e)}")
+
+
+test_dict = {
+    'absolute_path': 'Y:\\CloudMusic\\Aaron Zigman - Main Title.mp3',
+    'filename': 'Aaron Zigman - Main Title.mp3',
+    'extent_count': 1,
+    'start_byte': 687685632,
+    'length': 7163904,
+    'fragment_index': 1
+}
+
+CopyFileFromBytes(test_dict, target_path=r"Z:\RecoveredFiles")