ref: 99e1677b6bf577fb4db18f50a92df79ea47e9e0e
parent: c505373d1bbcad1e7861f6db054eddcfd5cac354
author: Ori Bernstein <ori@eigenstate.org>
date: Mon Jun 12 05:51:51 EDT 2017
Add missing file.
--- /dev/null
+++ b/lib/bio/mem.myr
@@ -1,0 +1,45 @@
+use std
+use "bio"
+
+pkg bio =
+ const mkmem : (buf : byte[:] -> file#)
+;;
+
+type mem = struct
+ buf : byte[:]
+ off : std.size
+;;
+
+const mkmem = {buf+ var mem : mem#
+
+ mem = std.mk([
+ .buf = buf,
+ .off = 0
+ ])
+
+ -> mk(Rd, [
+ .read = {buf; -> memread(mem, buf)},+ .write = {buf; -> memwrite(mem, buf)},+ .seek = {off; mem.off = std.clamp(off, 0, mem.buf.len); -> `std.Ok mem.off},+ .close = {; std.free(mem)},+ ])
+}
+
+const memread = {mem, dst+ var n
+
+ n = std.min(mem.buf.len - mem.off, dst.len)
+ std.slcp(dst[:n], mem.buf[mem.off:mem.off+n])
+ mem.off += n
+ -> `std.Ok n
+}
+
+const memwrite = {mem, src+ var n
+
+ n = std.min(mem.buf.len - mem.off, src.len)
+ std.slcp(mem.buf[mem.off:mem.off+n], src[:n])
+ mem.off += n
+ -> `std.Ok n
+}