1 files changed, 55 insertions, 6 deletions

diff --git a/cooker/call.c b/cooker/call.c
index bb53829..dd37fe9 100644
--- a/cooker/call.c
+++ b/cooker/call.c
@@ -72,7 +72,7 @@ static union value parse_metadata(struct gluten_ctx *g, struct field *f,
 		if (tag_offset.type == OFFSET_NULL)
 			die("   tag not found");
 
-		if ((*base_offset)->type == OFFSET_NULL) {
+		if ((*base_offset)->type == OFFSET_NULL || (f->flags & WBUF)) {
 			**base_offset = tag_offset;
 		} else if (f->flags & MASK || add) {
 			emit_bitwise(g, f->type, BITWISE_OR, offset, offset,
@@ -133,6 +133,10 @@ Examples of arguments:
 - STRING: abcd		write abcd to ro_data (using size), and pointer to it
 				parse_arg() passes ro_data offset
 
+- IOV: <tag>		write (one!) struct iovec with iov_base pointer to tag
+				parse_arg() passes null offset
+				parse_field() gives back data offset
+
 - STRUCT: 1, 2		write struct to ro_data, and pointer to it
 				parse_arg() passes ro_data offset
 
@@ -169,12 +173,38 @@ static union value parse_field(struct gluten_ctx *g, struct arg *args,
 	    (tmp1 = json_value_get_object(jvalue)) && is_metadata_obj(tmp1)) {
 		v = parse_metadata(g, f, &base_offset, offset, tmp1, dry_run,
 				   add);
-		if (v.v_num == 0)
+		if (!(f->flags & IOV) && v.v_num == 0)
+			return v;
+	}
+
+	if (f->flags & IOV) {
+		struct gluten_offset iov;
+		struct iovec *iovp;
+		intptr_t *msg_iov;
+
+		if (dry_run)
 			return v;
+
+		/* iov_base: v */
+		/* iov_len: at the moment from field */
+		msg_iov = (intptr_t *)gluten_ptr(&g->g, offset);
+
+		iov = gluten_rw_alloc(g, sizeof(struct iovec));
+		iovp = (struct iovec *)gluten_ptr(&g->g, iov);
+		iovp->iov_base = (void *)(intptr_t)base_offset->offset;
+		gluten_relocation_add(g, iov);
+
+		iovp->iov_len = f->size;
+
+		*msg_iov = iov.offset;
+		gluten_relocation_add(g, offset);
+
+		return v;
 	}
 
 	if (!jvalue && !(f->flags & SIZE))
 		return v;
+
 	switch (f->type) {
 	case USHORT:
 	case INT:
@@ -249,12 +279,28 @@ static union value parse_field(struct gluten_ctx *g, struct arg *args,
 
 			tmp1 = json_value_get_object(jvalue);
 			f_value = json_object_get_value(tmp1, f_inner->name);
-			debug("    parse struct internal value:%s",
+			debug("    parse struct, field %s, internal value:%s",
+			      f_inner->name,
 			      json_serialize_to_string(f_value));
-			if (!f_value)
+			if (!f_value && !(f_inner->flags & SIZE))
 				continue;
-			parse_field(g, args, &struct_start, index, f_inner,
-				    f_value, false, add);
+
+			if (f_inner->size && f_inner->type == SELECT) {
+				struct gluten_offset ptr_offset;
+				intptr_t *link;
+
+				ptr_offset = gluten_rw_alloc(g, f_inner->size);
+				parse_field(g, args, &ptr_offset, index, f_inner,
+					    f_value, false, add);
+
+				link = (intptr_t *)gluten_ptr(&g->g, offset);
+				*link = ptr_offset.offset;
+				gluten_relocation_add(g, offset);
+			} else {
+				parse_field(g, args, &struct_start, index, f_inner,
+					    f_value, false, add);
+			}
+
 			if (base_offset->type == OFFSET_NULL)
 				*base_offset = struct_start;
 		}
@@ -278,6 +324,9 @@ bool arg_needs_temp(struct field *f, int pos, JSON_Value *jvalue,
 	if (f->flags & COPY_ON_CALL)
 		return true;
 
+	if (f->flags & IOV)
+		return true;
+
 	if (f->flags & SIZE)
 		return false;