proper cmake

src/change_detectors/includes/ComparableFile.h

@@ -0,0 +1,43 @@
+//
+// Created by Stepan Usatiuk on 05.05.2023.
+//
+
+#ifndef SEMBACKUP_COMPARABLEFILE_H
+#define SEMBACKUP_COMPARABLEFILE_H
+
+#include <filesystem>
+#include <functional>
+#include <streambuf>
+
+#include "../../repo/includes/Repository.h"
+#include "../../repo/includes/objects/File.h"
+
+/// Helper class to allow comparing files from different sources
+/**
+ * As we are required to allow comparisons between a File in a repository and a file in filesystem,
+ * comparisons between two files that are already in a Repository,
+ * and between File%s that are in a repository cache and between files in the filesystem (when making backups),
+ * this helper class exists to provide a uniform interface to be used when calling ChangeDetector%s.
+ */
+struct ComparableFile {
+    /// Constructs a ComparableFile based on a File in a Repository
+    /// The resulting ComparableFile will have a #contents function that returns an instance of FileBuffer for given \p file
+    /// \param file    Constant reference to a File object
+    /// \param repo Constant pointer to Repository from which the File object was taken, must be valid during the lifetime of created ComparableFile
+    ComparableFile(const File &file, const Repository *repo);
+
+    /// Constructs a ComparableFile based on a file in the filesystem
+    /// The resulting ComparableFile will have a #contents function that returns an instance of std::filebuf for file at given path
+    /// \param p    Constant reference to an absolute path to the file
+    /// \param base Constant reference to a base path against which #path will be set
+    ComparableFile(const std::filesystem::path &p, const std::filesystem::path &base);
+
+    const std::string path;                                         ///< Relative path to the file
+    const File::Type type;                                          ///< File type
+    const unsigned long long bytes;                                 ///< Number of bytes in the file
+    const unsigned long long mtime;                                 ///< Timestamp of last file modification
+    const std::function<std::unique_ptr<std::streambuf>()> contents;///< Function that returns a unique pointer to a std::streambuf instance linked to the contents of the file
+};
+
+
+#endif//SEMBACKUP_COMPARABLEFILE_H