1 files changed, 48 insertions, 0 deletions
diff --git a/sector/sector.ha b/sector/sector.ha
new file mode 100644
index 0000000..50f417b
--- /dev/null
+++ b/sector/sector.ha
@@ -0,0 +1,48 @@
+use io;
+use types;
+
+use fmt;
+
+export const length: u64 = 512;
+
+export fn lba(no: u64) size = {
+	return no * length;
+};
+
+export type sector = struct {
+	buf: []u8,
+	fd: io::file,
+	lba_begin: u64,
+	lba_end: u64,
+};
+
+export fn map(fd: io::file, lba_begin: u64, lba_end: u64) sector = {
+	let self = sector {
+		buf = alloc([0...], (lba_end - lba_begin + 1)*length),
+		fd = fd,
+		lba_begin = lba_begin,
+		lba_end = lba_end
+	};
+
+	return self;
+};
+
+export fn finish(self: *sector) void = {
+	free(self.buf);
+};
+
+export fn fetch(self: *sector) void = {
+	// XXX proper error
+	io::seek(self.fd, (self.lba_begin * length): io::off, io::whence::SET)!;
+	io::read(self.fd, self.buf)!;
+};
+
+export fn commit(self: *sector) void = {
+	io::seek(self.fd, (self.lba_begin * length): io::off, io::whence::SET)!;
+	io::write(self.fd, self.buf)!;
+};
+
+export fn commit_at(self: *sector, fd: io::file, lba: u64) void = {
+	io::seek(fd, (lba * length): io::off, io::whence::SET)!;
+	io::write(fd, self.buf)!;
+};