1 files changed, 58 insertions, 0 deletions
diff --git a/bfs/blocks.ha b/bfs/blocks.ha
new file mode 100644
index 0000000..ec88e70
--- /dev/null
+++ b/bfs/blocks.ha
@@ -0,0 +1,58 @@
+use io;
+
+fn getblockdata(filesystem: *bfs, blockid: u64, data: []u8) (void | io::error) = {
+	const blockaddr = (blockid << filesystem.bootsector.blocksize): io::off;
+
+	pread(filesystem.device, data, blockaddr)?;
+};
+
+fn setblockdata(filesystem: *bfs, blockid: u64, data: []u8) (void | io::error) = {
+	const blockaddr = (blockid << filesystem.bootsector.blocksize): io::off;
+
+	pwrite(filesystem.device, data, blockaddr)?;
+};
+
+// Inode block: a block used to store
+// inodes
+export type inode_block = struct {
+	// Previous inode block containing
+	// free inodes, or 0
+	@offset(0) prevblock: u64,
+
+	// Next inode block containing
+	// free inodes, or 0
+	@offset(8) nextblock: u64,
+
+	// Next free inode in the block
+	@offset(16) nextinode: u64,
+
+	// Lowest yet to be allocated inode
+	@offset(24) freeinode: u64,
+
+	// Count of free inodes in block
+	@offset(32) freecount: u64,
+};
+
+export fn getinblock(filesystem: *bfs, blockid: u64, inblock: *inode_block) (void | io::error) = {
+	getblockdata(filesystem, blockid, inblock: *[size(inode_block)]u8)?;
+};
+
+export fn setinblock(filesystem: *bfs, blockid: u64, inblock: *inode_block) (void | io::error) = {
+	setblockdata(filesystem, blockid, inblock: *[size(inode_block)]u8)?;
+};
+
+// Free block: a block that has been
+// previously freed
+export type free_block = struct {
+	// Previous freeblock in freelist
+	// or 0
+	@offset(0) prevblock: u64,
+};
+
+export fn getfreeblock(filesystem: *bfs, blockid: u64, freeblock: *free_block) (void | io::error) = {
+	getblockdata(filesystem, blockid, freeblock: *[size(free_block)]u8)?;
+};
+
+export fn setfreeblock(filesystem: *bfs, blockid: u64, freeblock: *free_block) (void | io::error) = {
+	setblockdata(filesystem, blockid, freeblock: *[size(free_block)]u8)?;
+};