Initial commit of block device interface and emulated block device

emubd/lfs_emubd.h

@@ -0,0 +1,57 @@
+/*
+ * Block device emulated on standard files
+ *
+ * Copyright (c) 2017 Christopher Haster
+ * Distributed under the MIT license
+ */
+#ifndef LFS_EMUBD_H
+#define LFS_EMUBD_H
+
+#include "lfs_config.h"
+#include "lfs_bd.h"
+
+
+// The emu bd state
+typedef struct lfs_emubd {
+    char *path;
+    char *child;
+    struct lfs_bd_info info;
+} lfs_emubd_t;
+
+
+// Create a block device using path for the directory to store blocks
+lfs_error_t lfs_emubd_create(lfs_emubd_t *emu, const char *path);
+
+// Clean up memory associated with emu block device
+void lfs_emubd_destroy(lfs_emubd_t *emu);
+
+// Read a block
+lfs_error_t lfs_emubd_read(lfs_emubd_t *bd, uint8_t *buffer,
+        lfs_ino_t ino, lfs_off_t off, lfs_size_t size);
+
+// Program a block
+//
+// The block must have previously been erased.
+lfs_error_t lfs_emubd_write(lfs_emubd_t *bd, const uint8_t *buffer,
+        lfs_ino_t ino, lfs_off_t off, lfs_size_t size);
+
+// Erase a block
+//
+// A block must be erased before being programmed. The
+// state of an erased block is undefined.
+lfs_error_t lfs_emubd_erase(lfs_emubd_t *bd,
+        lfs_ino_t ino, lfs_off_t off, lfs_size_t size);
+
+// Sync the block device
+lfs_error_t lfs_emubd_sync(lfs_emubd_t *bd);
+
+// Get a description of the block device
+//
+// Any unknown information may be left unmodified
+lfs_error_t lfs_emubd_info(lfs_emubd_t *bd, struct lfs_bd_info *info);
+
+// Block device operations
+extern const struct lfs_bd_ops lfs_emubd_ops;
+
+
+#endif