4 files changed, 25 insertions, 2 deletions
diff --git a/lib9p/core_gen/c9util.py b/lib9p/core_gen/c9util.py
index 84fdee4..a304ff4 100644
--- a/lib9p/core_gen/c9util.py
+++ b/lib9p/core_gen/c9util.py
@@ -91,6 +91,8 @@ def typename(typ: idl.Type, parent: idl.StructMember | None = None) -> str:
     match typ:
         case idl.Primitive():
             if typ.value == 1 and parent and parent.cnt:  # SPECIAL (string)
+                if parent.membname == "data":  # SPECIAL (iovec)
+                    return f"struct {ident('_iovec')}"
                 return "[[gnu::nonstring]] char"
             return f"uint{typ.value*8}_t"
         case idl.Number():
diff --git a/lib9p/core_gen/c_marshal.py b/lib9p/core_gen/c_marshal.py
index 86d82e4..af8d582 100644
--- a/lib9p/core_gen/c_marshal.py
+++ b/lib9p/core_gen/c_marshal.py
@@ -334,6 +334,9 @@ def gen_c_marshal(versions: set[str], typs: list[idl.UserType]) -> str:
             if child.typ.static_size == 1:  # SPECIAL (zerocopy)
                 if path.root.typname == "stat":  # SPECIAL (stat)
                     ret += f"{'\t'*indent_lvl()}MARSHAL_BYTES(ctx, {path.c_str('val->')[:-3]}, {cnt_str});\n"
+                elif c9util.typename(child.typ, child) == f"struct {c9util.ident("_iovec")}":  # SPECIAL (iovec)
+                    ret += f"{'\t'*indent_lvl()}for (int iov_i = 0; iov_i < {path.c_str('val->')[:-3]}->iovcnt; iov_i++)\n"
+                    ret += f"{'\t'*(indent_lvl()+1)}MARSHAL_BYTES_ZEROCOPY(ctx, {path.c_str('val->')[:-3]}->iov[iov_i].iov_base, {path.c_str('val->')[:-3]}->iov[iov_i].iov_len);\n"
                 else:
                     ret += f"{'\t'*indent_lvl()}MARSHAL_BYTES_ZEROCOPY(ctx, {path.c_str('val->')[:-3]}, {cnt_str});\n"
                 return idlutil.WalkCmd.KEEP_GOING, pop
diff --git a/lib9p/core_gen/c_unmarshal.py b/lib9p/core_gen/c_unmarshal.py
index 206a85b..c510e44 100644
--- a/lib9p/core_gen/c_unmarshal.py
+++ b/lib9p/core_gen/c_unmarshal.py
@@ -100,7 +100,14 @@ def gen_c_unmarshal(versions: set[str], typs: list[idl.UserType]) -> str:
                 cnt_str = path.parent().add(child.cnt).c_str("out->")
                 cnt_typ = c9util.typename(child.cnt.typ)
             if child.typ.static_size == 1:  # SPECIAL (zerocopy)
-                ret += f"{'\t'*indent_lvl()}UNMARSHAL_BYTES(ctx, {path.c_str('out->')[:-3]}, {cnt_str});\n"
+                if c9util.typename(child.typ, child) == f"struct {c9util.ident('_iovec')}":  # SPECIAL (iovec)
+                    ret += f"{'\t'*indent_lvl()}out->{child.membname}.iov = ctx->extra;\n"
+                    ret += f"{'\t'*indent_lvl()}ctx->extra += sizeof(out->{child.membname}.iov[0]);\n"
+                    ret += f"{'\t'*indent_lvl()}out->{child.membname}.iov->iov_base = &ctx->net_bytes[ctx->net_offset];\n"
+                    ret += f"{'\t'*indent_lvl()}out->{child.membname}.iov->iov_len = out->{child.cnt.membname};\n"
+                    ret += f"{'\t'*indent_lvl()}out->{child.membname}.iovcnt = 1;\n"
+                else:
+                    ret += f"{'\t'*indent_lvl()}UNMARSHAL_BYTES(ctx, {path.c_str('out->')[:-3]}, {cnt_str});\n"
                 return idlutil.WalkCmd.KEEP_GOING, pop
             ret += f"{'\t'*indent_lvl()}{path.c_str('out->')[:-3]} = extra;\n"
             ret += f"{'\t'*indent_lvl()}extra += sizeof({path.c_str('out->')[:-3]}[0]) * {cnt_str};\n"
diff --git a/lib9p/core_gen/h.py b/lib9p/core_gen/h.py
index 8c381f8..6ead5ba 100644
--- a/lib9p/core_gen/h.py
+++ b/lib9p/core_gen/h.py
@@ -162,6 +162,11 @@ def gen_h(versions: set[str], typs: list[idl.UserType]) -> str:
 #ifndef _LIB9P_CORE_H_
 \t#error Do not include <lib9p/_core_generated.h> directly; include <lib9p/core.h> instead
 #endif
+
+struct {c9util.ident('_iovec_list')} {{
+\tstruct iovec *iov;
+\tint           iovcnt;
+}};
 """
     id2typ: dict[int, idl.Message] = {}
     for msg in [msg for msg in typs if isinstance(msg, idl.Message)]:
@@ -523,7 +528,13 @@ def gen_struct(typ: idl.Struct) -> str:  # and idl.Message
             if member.val:
                 continue
             ret += cutil.ifdef_push(2, c9util.ver_ifdef(member.in_versions))
-            ret += f"\t{c9util.typename(member.typ, member):<{typewidth}}  {'*' if member.cnt else ' '}{member.membname};\n"
+            ptr = bool(member.cnt)
+            if (
+                c9util.typename(member.typ, member)
+                == f"struct {c9util.ident('_iovec')}"
+            ):  # SPECIAL (zerocopy)
+                ptr = False
+            ret += f"\t{c9util.typename(member.typ, member):<{typewidth}}  {'*' if ptr else ' '}{member.membname};\n"
         ret += cutil.ifdef_pop(1)
     ret += "};\n"
     return ret