Added backing signatures

src/backing.h

@@ -9,19 +9,49 @@
 #define BACKING_POOL_DIR "/var/lib/sandbox/backings"
 #define MAX_BACKING_LENGTH 256
 
-/// @brief Checks whether the given backing id is valid.
-/// @param backing_id The backing id to check.
-/// @return True if the backing id is valid, false otherwise.
+typedef struct {
+	DiskInfo disk_info;
+} BackingInfo;
+
+/// @brief Checks whether the given backing disk id is valid.
+/// @param backing_id The backing disk id to check.
+/// @return True if the backing disk id is valid, false otherwise.
 bool is_valid_backing_id(const char* backing_id);
 
-/// @brief Gets the path of the given backing.
-/// @param backing_id The backing id.
+/// @brief Gets the path of the given backing disk.
+/// @param backing_id The backing disk id.
 /// @param out_path The pointer to the output path string. The caller is responsible for freeing the memory.
 /// @return The result of the operation.
 Result get_backing_path(const char* backing_id, char** out_path);
 
-/// @brief Checks whether the given backing exists in the pool.
-/// @param backing_id The backing id.
+/// @brief Checks whether the given backing disk exists in the pool.
+/// @param backing_id The backing disk id.
 /// @param out_exists The pointer to the output boolean.
 /// @return The result of the operation.
-Result backing_exists(const char* backing_id, bool* out_exists);
+Result backing_exists(const char* backing_id, bool* out_exists);
+
+/// @brief Adds a backing disk to the pool from an entry.
+/// @param backing_id The backing disk id.
+/// @param entry_id The entry id.
+/// @return The result of the operation.
+Result add_backing_from_entry(const char* backing_id, const char* entry_id);
+
+/// @brief Removes a backing disk from the pool, and removes any backing disks that uses it.
+/// @param backing_id The backing disk id.
+/// @return The result of the operation.
+Result remove_backing(const char* backing_id);
+
+/// @brief Lists the backing disks in the pool.
+/// @param out_backings The pointer to the null-terminated array of backing disk ids. The caller is responsible for freeing the memory of the array and its elements.
+/// @return The result of the operation.
+Result list_backings(char*** out_backings, size_t* out_count);
+
+/// @brief Gathers information about a backing disk.
+/// @param backing_id The backing disk id.
+/// @param out_info The information about the backing disk.
+/// @return The result of the operation.
+Result get_backing_info(const char* backing_id, BackingInfo* out_info);
+
+/// @brief Frees the resources used by the given backing disk information.
+/// @param info The backing disk information to free.
+void free_backing_info(BackingInfo* info);