[LEDE-DEV] [PATCH] Allow sending a fd in a ubus_request
amine.ahd
amine.ahd at gmail.com
Thu Dec 8 04:47:40 PST 2016
In the current implementation, a fd can be sent in the reply to an existing request which can be inefficient in certain cases.
Example: when you want to create a pipe between two process with the help of a 3rd process acting as a manager: you need 3 pipe with the current implementation and only one pipe with this patch.
Basically the patch adds two new functions (ubus_invoke_fd and ubus_invoke_async_fd) that are very similar to the original functions (open to any other alternatives here) and a new msg type (UBUS_MSG_INVOKE_FD) to copy the received fd to req_fd when processing the invocation.
---
libubus-internal.h | 4 +++-
libubus-obj.c | 19 ++++++++++++++-----
libubus-req.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
libubus.c | 3 ++-
libubus.h | 9 +++++++++
ubusd.c | 1 -
ubusd_proto.c | 13 +++++++++++--
ubusmsg.h | 2 ++
8 files changed, 90 insertions(+), 10 deletions(-)
diff --git a/libubus-internal.h b/libubus-internal.h
index f62edc3..9513fb7 100644
--- a/libubus-internal.h
+++ b/libubus-internal.h
@@ -24,7 +24,9 @@ int ubus_send_msg(struct ubus_context *ctx, uint32_t seq,
void ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf, int fd);
int __hidden ubus_start_request(struct ubus_context *ctx, struct ubus_request *req,
struct blob_attr *msg, int cmd, uint32_t peer);
-void ubus_process_obj_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf);
+int __hidden ubus_start_request_fd(struct ubus_context *ctx, struct ubus_request *req,
+ struct blob_attr *msg, int cmd, uint32_t peer, int fd);
+void ubus_process_obj_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf, int fd);
void ubus_process_req_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf, int fd);
void __hidden ubus_poll_data(struct ubus_context *ctx, int timeout);
diff --git a/libubus-obj.c b/libubus-obj.c
index 990d04b..94af630 100644
--- a/libubus-obj.c
+++ b/libubus-obj.c
@@ -44,11 +44,13 @@ ubus_process_notify(struct ubus_context *ctx, struct ubus_msghdr *hdr,
}
static void
ubus_process_invoke(struct ubus_context *ctx, struct ubus_msghdr *hdr,
- struct ubus_object *obj, struct blob_attr **attrbuf)
+ struct ubus_object *obj, struct blob_attr **attrbuf, int fd)
{
struct ubus_request_data req = {
.fd = -1,
+ .req_fd = fd,
};
+
int method;
int ret;
bool no_reply = false;
@@ -94,11 +96,13 @@ found:
send:
ubus_complete_deferred_request(ctx, &req, ret);
}
-
-void __hidden ubus_process_obj_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf)
+
+void __hidden ubus_process_obj_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf, int fd)
{
void (*cb)(struct ubus_context *, struct ubus_msghdr *,
struct ubus_object *, struct blob_attr **);
+ void (*cb_fd)(struct ubus_context *, struct ubus_msghdr *,
+ struct ubus_object *, struct blob_attr **, int fd);
struct ubus_msghdr *hdr = &buf->hdr;
struct blob_attr **attrbuf;
struct ubus_object *obj;
@@ -114,7 +118,9 @@ void __hidden ubus_process_obj_msg(struct ubus_context *ctx, struct ubus_msghdr_
switch (hdr->type) {
case UBUS_MSG_INVOKE:
- cb = ubus_process_invoke;
+ case UBUS_MSG_INVOKE_FD:
+ cb_fd = ubus_process_invoke;
+ cb = NULL;
break;
case UBUS_MSG_UNSUBSCRIBE:
cb = ubus_process_unsubscribe;
@@ -131,7 +137,10 @@ void __hidden ubus_process_obj_msg(struct ubus_context *ctx, struct ubus_msghdr_
buf->data = NULL;
}
- cb(ctx, hdr, obj, attrbuf);
+ if (hdr->type == UBUS_MSG_INVOKE || hdr->type == UBUS_MSG_INVOKE_FD)
+ cb_fd(ctx, hdr, obj, attrbuf, fd);
+ else
+ cb(ctx, hdr, obj, attrbuf);
if (prev_data) {
if (buf->data)
diff --git a/libubus-req.c b/libubus-req.c
index 416adab..9913f1e 100644
--- a/libubus-req.c
+++ b/libubus-req.c
@@ -62,9 +62,27 @@ int __hidden ubus_start_request(struct ubus_context *ctx, struct ubus_request *r
req->ctx = ctx;
req->peer = peer;
req->seq = ++ctx->request_seq;
+
return ubus_send_msg(ctx, req->seq, msg, cmd, peer, -1);
}
+int __hidden ubus_start_request_fd(struct ubus_context *ctx, struct ubus_request *req,
+ struct blob_attr *msg, int cmd, uint32_t peer, int fd)
+{
+ memset(req, 0, sizeof(*req));
+
+ if (msg && blob_pad_len(msg) > UBUS_MAX_MSGLEN)
+ return -1;
+
+ INIT_LIST_HEAD(&req->list);
+ INIT_LIST_HEAD(&req->pending);
+ req->ctx = ctx;
+ req->peer = peer;
+ req->seq = ++ctx->request_seq;
+
+ return ubus_send_msg(ctx, req->seq, msg, cmd, peer, fd);
+}
+
void ubus_abort_request(struct ubus_context *ctx, struct ubus_request *req)
{
if (list_empty(&req->list))
@@ -224,6 +242,21 @@ int ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method
return 0;
}
+
+int ubus_invoke_async_fd(struct ubus_context *ctx, uint32_t obj, const char *method,
+ struct blob_attr *msg, struct ubus_request *req, int fd)
+{
+ blob_buf_init(&b, 0);
+ blob_put_int32(&b, UBUS_ATTR_OBJID, obj);
+ blob_put_string(&b, UBUS_ATTR_METHOD, method);
+ if (msg)
+ blob_put(&b, UBUS_ATTR_DATA, blob_data(msg), blob_len(msg));
+
+ if (ubus_start_request_fd(ctx, req, b.head, UBUS_MSG_INVOKE_FD, obj, fd) < 0)
+ return UBUS_STATUS_INVALID_ARGUMENT;
+ return 0;
+}
+
int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
struct blob_attr *msg, ubus_data_handler_t cb, void *priv,
int timeout)
@@ -240,6 +273,22 @@ int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
return ubus_complete_request(ctx, &req, timeout);
}
+int ubus_invoke_fd(struct ubus_context *ctx, uint32_t obj, const char *method,
+ struct blob_attr *msg, ubus_data_handler_t cb, void *priv,
+ int timeout, int fd)
+{
+ struct ubus_request req;
+ int rc;
+
+ rc = ubus_invoke_async_fd(ctx, obj, method, msg, &req, fd);
+ if (rc)
+ return rc;
+
+ req.data_cb = cb;
+ req.priv = priv;
+ return ubus_complete_request(ctx, &req, timeout);
+}
+
static void
ubus_notify_complete_cb(struct ubus_request *req, int ret)
{
diff --git a/libubus.c b/libubus.c
index 8163ff7..d9602e7 100644
--- a/libubus.c
+++ b/libubus.c
@@ -96,6 +96,7 @@ ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf, int fd)
break;
case UBUS_MSG_INVOKE:
+ case UBUS_MSG_INVOKE_FD:
case UBUS_MSG_UNSUBSCRIBE:
case UBUS_MSG_NOTIFY:
if (ctx->stack_depth) {
@@ -103,7 +104,7 @@ ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr_buf *buf, int fd)
break;
}
- ubus_process_obj_msg(ctx, buf);
+ ubus_process_obj_msg(ctx, buf, fd);
break;
case UBUS_MSG_MONITOR:
if (ctx->monitor_cb)
diff --git a/libubus.h b/libubus.h
index 07239d6..0a05416 100644
--- a/libubus.h
+++ b/libubus.h
@@ -188,6 +188,7 @@ struct ubus_request_data {
/* internal use */
bool deferred;
int fd;
+ int req_fd; /* fd received from the initial request */
};
struct ubus_request {
@@ -336,6 +337,14 @@ int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
int ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method,
struct blob_attr *msg, struct ubus_request *req);
+int ubus_invoke_fd(struct ubus_context *ctx, uint32_t obj, const char *method,
+ struct blob_attr *msg, ubus_data_handler_t cb, void *priv,
+ int timeout, int fd);
+
+/* asynchronous version of ubus_invoke() */
+int ubus_invoke_async_fd(struct ubus_context *ctx, uint32_t obj, const char *method,
+ struct blob_attr *msg, struct ubus_request *req, int fd);
+
/* send a reply to an incoming object method call */
int ubus_send_reply(struct ubus_context *ctx, struct ubus_request_data *req,
struct blob_attr *msg);
diff --git a/ubusd.c b/ubusd.c
index 7279a70..cf38c31 100644
--- a/ubusd.c
+++ b/ubusd.c
@@ -345,7 +345,6 @@ static bool get_next_connection(int fd)
uloop_fd_add(&cl->sock, ULOOP_READ | ULOOP_EDGE_TRIGGER);
else
close(client_fd);
-
return true;
}
diff --git a/ubusd_proto.c b/ubusd_proto.c
index b591384..596a981 100644
--- a/ubusd_proto.c
+++ b/ubusd_proto.c
@@ -80,11 +80,16 @@ void
ubus_proto_send_msg_from_blob(struct ubus_client *cl, struct ubus_msg_buf *ub,
uint8_t type)
{
+ /* keep the fd to be passed if it is UBUS_MSG_INVOKE_FD */
+ int fd = ub->fd;
ub = ubus_reply_from_blob(ub, true);
if (!ub)
return;
ub->hdr.type = type;
+ if(type == UBUS_MSG_INVOKE_FD)
+ ub->fd = fd;
+
ubus_msg_send(cl, ub, true);
}
@@ -239,7 +244,10 @@ ubusd_forward_invoke(struct ubus_client *cl, struct ubus_object *obj,
if (data)
blob_put(&b, UBUS_ATTR_DATA, blob_data(data), blob_len(data));
- ubus_proto_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE);
+ if (ub->hdr.type == UBUS_MSG_INVOKE_FD)
+ ubus_proto_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE_FD);
+ else
+ ubus_proto_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE);
}
static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
@@ -428,6 +436,7 @@ static const ubus_cmd_cb handlers[__UBUS_MSG_LAST] = {
[UBUS_MSG_REMOVE_OBJECT] = ubusd_handle_remove_object,
[UBUS_MSG_LOOKUP] = ubusd_handle_lookup,
[UBUS_MSG_INVOKE] = ubusd_handle_invoke,
+ [UBUS_MSG_INVOKE_FD] = ubusd_handle_invoke,
[UBUS_MSG_STATUS] = ubusd_handle_response,
[UBUS_MSG_DATA] = ubusd_handle_response,
[UBUS_MSG_SUBSCRIBE] = ubusd_handle_add_watch,
@@ -446,7 +455,7 @@ void ubusd_proto_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub
if (ub->hdr.type < __UBUS_MSG_LAST)
cb = handlers[ub->hdr.type];
- if (ub->hdr.type != UBUS_MSG_STATUS)
+ if (ub->hdr.type != UBUS_MSG_STATUS && ub->hdr.type != UBUS_MSG_INVOKE_FD)
ubus_msg_close_fd(ub);
if (cb)
diff --git a/ubusmsg.h b/ubusmsg.h
index 398b126..aa3955c 100644
--- a/ubusmsg.h
+++ b/ubusmsg.h
@@ -51,6 +51,8 @@ enum ubus_msg_type {
/* invoke a method on a single object */
UBUS_MSG_INVOKE,
+ /* invoke a method and send a fd along */
+ UBUS_MSG_INVOKE_FD,
UBUS_MSG_ADD_OBJECT,
UBUS_MSG_REMOVE_OBJECT,
--
2.6.6
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