ubus/libubus.c
2011-01-31 19:55:07 +01:00

709 lines
15 KiB
C

#include <sys/types.h>
#include <sys/uio.h>
#include <sys/socket.h>
#include <unistd.h>
#include <libubox/blob.h>
#include <libubox/blobmsg.h>
#include <libubox/usock.h>
#include "libubus.h"
#include "ubusmsg.h"
#define DEBUG 1
#ifdef DEBUG
#define DPRINTF(_format, ...) fprintf(stderr, "ubus: " _format, ## __VA_ARGS__)
#else
#define DPRINTF(...) do {} while(0)
#endif
#define STATIC_IOV(_var) { .iov_base = (char *) &(_var), .iov_len = sizeof(_var) }
const char *__ubus_strerror[__UBUS_STATUS_LAST] = {
[UBUS_STATUS_OK] = "Success",
[UBUS_STATUS_INVALID_COMMAND] = "Invalid command",
[UBUS_STATUS_INVALID_ARGUMENT] = "Invalid argument",
[UBUS_STATUS_METHOD_NOT_FOUND] = "Method not found",
[UBUS_STATUS_NOT_FOUND] = "Not found",
[UBUS_STATUS_NO_DATA] = "No response",
};
static struct blob_buf b;
static const struct blob_attr_info ubus_policy[UBUS_ATTR_MAX] = {
[UBUS_ATTR_STATUS] = { .type = BLOB_ATTR_INT32 },
[UBUS_ATTR_OBJID] = { .type = BLOB_ATTR_INT32 },
[UBUS_ATTR_OBJPATH] = { .type = BLOB_ATTR_STRING },
[UBUS_ATTR_METHOD] = { .type = BLOB_ATTR_STRING },
};
static struct blob_attr *attrbuf[UBUS_ATTR_MAX];
struct ubus_pending_data {
struct list_head list;
int type;
struct blob_attr data[];
};
static int ubus_cmp_id(const void *k1, const void *k2, void *ptr)
{
const uint32_t *id1 = k1, *id2 = k2;
if (*id1 < *id2)
return -1;
else
return *id1 > *id2;
}
static struct blob_attr **ubus_parse_msg(struct blob_attr *msg)
{
blob_parse(msg, attrbuf, ubus_policy, UBUS_ATTR_MAX);
return attrbuf;
}
const char *ubus_strerror(int error)
{
static char err[32];
if (error < 0 || error >= __UBUS_STATUS_LAST)
goto out;
if (!__ubus_strerror[error])
goto out;
return __ubus_strerror[error];
out:
sprintf(err, "Unknown error: %d", error);
return err;
}
static int ubus_send_msg(struct ubus_context *ctx, uint32_t seq,
struct blob_attr *msg, int cmd, uint32_t peer)
{
struct ubus_msghdr hdr;
struct iovec iov[2] = {
STATIC_IOV(hdr)
};
hdr.version = 0;
hdr.type = cmd;
hdr.seq = seq;
hdr.peer = peer;
if (!msg) {
blob_buf_init(&b, 0);
msg = b.head;
}
iov[1].iov_base = (char *) msg;
iov[1].iov_len = blob_raw_len(msg);
return writev(ctx->sock.fd, iov, 2);
}
static int ubus_start_request(struct ubus_context *ctx, struct ubus_request *req,
struct blob_attr *msg, int cmd, uint32_t peer)
{
memset(req, 0, sizeof(*req));
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);
}
static bool recv_retry(int fd, struct iovec *iov, bool wait)
{
int bytes;
while (iov->iov_len > 0) {
bytes = read(fd, iov->iov_base, iov->iov_len);
if (bytes < 0) {
bytes = 0;
if (errno == EINTR)
continue;
if (errno != EAGAIN) {
perror("read");
return false;
}
}
if (!wait && !bytes)
return false;
wait = true;
iov->iov_len -= bytes;
iov->iov_base += bytes;
}
return true;
}
static bool ubus_validate_hdr(struct ubus_msghdr *hdr)
{
if (hdr->version != 0)
return false;
if (blob_raw_len(hdr->data) < sizeof(*hdr->data))
return false;
if (blob_raw_len(hdr->data) + sizeof(*hdr) > UBUS_MAX_MSGLEN)
return false;
return true;
}
static bool get_next_msg(struct ubus_context *ctx, bool wait)
{
struct iovec iov = STATIC_IOV(ctx->msgbuf.hdr);
/* receive header + start attribute */
iov.iov_len += sizeof(struct blob_attr);
if (!recv_retry(ctx->sock.fd, &iov, wait))
return false;
iov.iov_len = blob_len(ctx->msgbuf.hdr.data);
if (iov.iov_len > 0 && !recv_retry(ctx->sock.fd, &iov, true))
return false;
return ubus_validate_hdr(&ctx->msgbuf.hdr);
}
static bool ubus_get_status(struct ubus_msghdr *hdr, int *ret)
{
ubus_parse_msg(hdr->data);
if (!attrbuf[UBUS_ATTR_STATUS])
return false;
*ret = blob_get_int32(attrbuf[UBUS_ATTR_STATUS]);
return true;
}
static void req_data_cb(struct ubus_request *req, int type, struct blob_attr *data)
{
struct blob_attr **attr;
if (req->raw_data_cb)
req->raw_data_cb(req, type, data);
if (!req->data_cb)
return;
attr = ubus_parse_msg(data);
req->data_cb(req, type, attr[UBUS_ATTR_DATA]);
}
static void ubus_process_req_data(struct ubus_request *req)
{
struct ubus_pending_data *data;
while (!list_empty(&req->pending)) {
data = list_first_entry(&req->pending,
struct ubus_pending_data, list);
list_del(&data->list);
if (!req->cancelled)
req_data_cb(req, data->type, data->data);
free(data);
}
}
static void ubus_req_complete_cb(struct ubus_request *req)
{
ubus_complete_handler_t cb = req->complete_cb;
if (!cb)
return;
req->complete_cb = NULL;
cb(req, req->status_code);
}
static int ubus_process_req_status(struct ubus_request *req, struct ubus_msghdr *hdr)
{
int ret = UBUS_STATUS_INVALID_ARGUMENT;
if (!list_empty(&req->list))
list_del(&req->list);
ubus_get_status(hdr, &ret);
req->peer = hdr->peer;
req->status_msg = true;
req->status_code = ret;
if (!req->blocked)
ubus_req_complete_cb(req);
return ret;
}
static void ubus_req_data(struct ubus_request *req, struct ubus_msghdr *hdr)
{
struct ubus_pending_data *data;
int len;
if (!req->blocked) {
req->blocked = true;
req_data_cb(req, hdr->type, hdr->data);
ubus_process_req_data(req);
req->blocked = false;
if (req->status_msg)
ubus_req_complete_cb(req);
return;
}
len = blob_raw_len(hdr->data);
data = calloc(1, sizeof(*data) + len);
if (!data)
return;
data->type = hdr->type;
memcpy(data->data, hdr->data, len);
list_add(&data->list, &req->pending);
}
static struct ubus_request *ubus_find_request(struct ubus_context *ctx, uint32_t seq, uint32_t peer)
{
struct ubus_request *req;
list_for_each_entry(req, &ctx->requests, list) {
if (seq != req->seq || peer != req->peer)
continue;
return req;
}
return NULL;
}
static void ubus_process_invoke(struct ubus_context *ctx, struct ubus_msghdr *hdr)
{
struct ubus_request_data req;
struct ubus_object *obj;
uint32_t objid = 0;
int method;
int ret = 0;
ubus_parse_msg(hdr->data);
if (!attrbuf[UBUS_ATTR_OBJID])
return;
objid = blob_get_int32(attrbuf[UBUS_ATTR_OBJID]);
if (!attrbuf[UBUS_ATTR_METHOD]) {
ret = UBUS_STATUS_INVALID_ARGUMENT;
goto send;
}
obj = avl_find_element(&ctx->objects, &objid, obj, avl);
if (!obj) {
ret = UBUS_STATUS_NOT_FOUND;
goto send;
}
for (method = 0; method < obj->n_methods; method++)
if (!strcmp(obj->methods[method].name,
blob_data(attrbuf[UBUS_ATTR_METHOD])))
goto found;
/* not found */
ret = UBUS_STATUS_METHOD_NOT_FOUND;
goto send;
found:
req.object = objid;
req.peer = hdr->peer;
req.seq = hdr->seq;
ret = obj->methods[method].handler(ctx, obj, &req,
obj->methods[method].name,
attrbuf[UBUS_ATTR_DATA]);
send:
blob_buf_init(&b, 0);
blob_put_int32(&b, UBUS_ATTR_STATUS, ret);
blob_put_int32(&b, UBUS_ATTR_OBJID, objid);
ubus_send_msg(ctx, hdr->seq, b.head, UBUS_MSG_STATUS, hdr->peer);
}
static void ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr *hdr)
{
struct ubus_request *req;
switch(hdr->type) {
case UBUS_MSG_STATUS:
req = ubus_find_request(ctx, hdr->seq, hdr->peer);
if (!req)
break;
ubus_process_req_status(req, hdr);
break;
case UBUS_MSG_DATA:
req = ubus_find_request(ctx, hdr->seq, hdr->peer);
if (req && (req->data_cb || req->raw_data_cb))
ubus_req_data(req, hdr);
break;
case UBUS_MSG_INVOKE:
ubus_process_invoke(ctx, hdr);
break;
default:
DPRINTF("unknown message type: %d\n", hdr->type);
break;
}
}
void ubus_abort_request(struct ubus_context *ctx, struct ubus_request *req)
{
if (!list_empty(&req->list))
return;
req->cancelled = true;
ubus_process_req_data(req);
list_del(&req->list);
}
void ubus_complete_request_async(struct ubus_context *ctx, struct ubus_request *req)
{
if (!list_empty(&req->list))
return;
list_add(&req->list, &ctx->requests);
}
static void ubus_handle_data(struct uloop_fd *u, unsigned int events)
{
struct ubus_context *ctx = container_of(u, struct ubus_context, sock);
struct ubus_msghdr *hdr = &ctx->msgbuf.hdr;
while (get_next_msg(ctx, false))
ubus_process_msg(ctx, hdr);
if (u->eof)
ctx->connection_lost(ctx);
}
int ubus_complete_request(struct ubus_context *ctx, struct ubus_request *req)
{
struct ubus_msghdr *hdr = &ctx->msgbuf.hdr;
if (!list_empty(&req->list))
list_del(&req->list);
while (1) {
if (req->status_msg)
return req->status_code;
if (req->cancelled)
return UBUS_STATUS_NO_DATA;
if (!get_next_msg(ctx, true))
return UBUS_STATUS_NO_DATA;
if (hdr->seq != req->seq || hdr->peer != req->peer)
goto skip;
switch(hdr->type) {
case UBUS_MSG_STATUS:
return ubus_process_req_status(req, hdr);
case UBUS_MSG_DATA:
if (req->data_cb || req->raw_data_cb)
ubus_req_data(req, hdr);
continue;
default:
goto skip;
}
skip:
ubus_process_msg(ctx, hdr);
}
}
struct ubus_lookup_request {
struct ubus_request req;
ubus_lookup_handler_t cb;
};
static void ubus_lookup_cb(struct ubus_request *ureq, int type, struct blob_attr *msg)
{
struct ubus_lookup_request *req;
struct ubus_object_data obj;
struct blob_attr **attr;
req = container_of(ureq, struct ubus_lookup_request, req);
attr = ubus_parse_msg(msg);
if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_OBJPATH] ||
!attr[UBUS_ATTR_OBJTYPE])
return;
memset(&obj, 0, sizeof(obj));
obj.id = blob_get_int32(attr[UBUS_ATTR_OBJID]);
obj.path = blob_data(attr[UBUS_ATTR_OBJPATH]);
obj.type_id = blob_get_int32(attr[UBUS_ATTR_OBJTYPE]);
obj.signature = attr[UBUS_ATTR_SIGNATURE];
req->cb(ureq->ctx, &obj, ureq->priv);
}
int ubus_lookup(struct ubus_context *ctx, const char *path,
ubus_lookup_handler_t cb, void *priv)
{
struct ubus_lookup_request lookup;
blob_buf_init(&b, 0);
if (path)
blob_put_string(&b, UBUS_ATTR_OBJPATH, path);
ubus_start_request(ctx, &lookup.req, b.head, UBUS_MSG_LOOKUP, 0);
lookup.req.raw_data_cb = ubus_lookup_cb;
lookup.req.priv = priv;
lookup.cb = cb;
return ubus_complete_request(ctx, &lookup.req);
}
static void ubus_lookup_id_cb(struct ubus_request *req, int type, struct blob_attr *msg)
{
struct blob_attr **attr;
uint32_t *id = req->priv;
attr = ubus_parse_msg(msg);
if (!attr[UBUS_ATTR_OBJID])
return;
*id = blob_get_int32(attr[UBUS_ATTR_OBJID]);
}
int ubus_lookup_id(struct ubus_context *ctx, const char *path, uint32_t *id)
{
struct ubus_request req;
blob_buf_init(&b, 0);
if (path)
blob_put_string(&b, UBUS_ATTR_OBJPATH, path);
ubus_start_request(ctx, &req, b.head, UBUS_MSG_LOOKUP, 0);
req.raw_data_cb = ubus_lookup_id_cb;
req.priv = id;
return ubus_complete_request(ctx, &req);
}
int ubus_send_reply(struct ubus_context *ctx, struct ubus_request_data *req,
struct blob_attr *msg)
{
int ret;
blob_buf_init(&b, 0);
blob_put_int32(&b, UBUS_ATTR_OBJID, req->object);
blob_put(&b, UBUS_ATTR_DATA, blob_data(msg), blob_len(msg));
ret = ubus_send_msg(ctx, req->seq, b.head, UBUS_MSG_DATA, req->peer);
if (ret < 0)
return UBUS_STATUS_NO_DATA;
return 0;
}
void ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method,
struct blob_attr *msg, struct ubus_request *req)
{
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));
ubus_start_request(ctx, req, b.head, UBUS_MSG_INVOKE, obj);
}
int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
struct blob_attr *msg, ubus_data_handler_t cb, void *priv)
{
struct ubus_request req;
ubus_invoke_async(ctx, obj, method, msg, &req);
req.data_cb = cb;
req.priv = priv;
return ubus_complete_request(ctx, &req);
}
static void ubus_publish_cb(struct ubus_request *req, int type, struct blob_attr *msg)
{
struct ubus_object *obj = req->priv;
ubus_parse_msg(msg);
if (!attrbuf[UBUS_ATTR_OBJID])
return;
obj->id = blob_get_int32(attrbuf[UBUS_ATTR_OBJID]);
if (attrbuf[UBUS_ATTR_OBJTYPE])
obj->type->id = blob_get_int32(attrbuf[UBUS_ATTR_OBJTYPE]);
obj->avl.key = &obj->id;
avl_insert(&req->ctx->objects, &obj->avl);
}
static bool ubus_push_table_data(const struct ubus_signature **sig, int *rem, bool array)
{
const struct ubus_signature *cur;
bool nest_type;
void *nest;
while (rem) {
cur = (*sig)++;
(*rem)--;
switch(cur->type) {
case UBUS_SIGNATURE_END:
return !array;
case BLOBMSG_TYPE_INT32:
case BLOBMSG_TYPE_STRING:
blobmsg_add_u32(&b, cur->name, cur->type);
break;
case BLOBMSG_TYPE_TABLE:
case BLOBMSG_TYPE_ARRAY:
nest_type = cur->type == BLOBMSG_TYPE_ARRAY;
nest = blobmsg_open_nested(&b, cur->name, nest_type);
if (!ubus_push_table_data(sig, rem, nest_type))
return false;
blobmsg_close_table(&b, nest);
break;
default:
return false;
}
if (array)
return true;
}
return false;
}
static bool ubus_push_object_type(struct ubus_object_type *type)
{
void *s, *m;
int rem = type->n_signature;
const struct ubus_signature *sig = type->signature;
s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
while (rem) {
if (sig->type != UBUS_SIGNATURE_METHOD)
return false;
m = blobmsg_open_table(&b, sig->name);
sig++;
rem--;
if (!ubus_push_table_data(&sig, &rem, false))
return false;
blobmsg_close_table(&b, m);
}
blob_nest_end(&b, s);
return true;
}
int ubus_publish(struct ubus_context *ctx, struct ubus_object *obj)
{
struct ubus_request req;
int ret;
if (obj->id || !obj->name || !obj->type)
return UBUS_STATUS_INVALID_ARGUMENT;
blob_buf_init(&b, 0);
blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->name);
if (obj->type->id)
blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id);
else if (!ubus_push_object_type(obj->type))
return UBUS_STATUS_INVALID_ARGUMENT;
ubus_start_request(ctx, &req, b.head, UBUS_MSG_PUBLISH, 0);
req.raw_data_cb = ubus_publish_cb;
req.priv = obj;
ret = ubus_complete_request(ctx, &req);
if (ret)
return ret;
if (!obj->id)
return UBUS_STATUS_NO_DATA;
return 0;
}
void ubus_default_connection_lost(struct ubus_context *ctx)
{
if (ctx->sock.registered)
uloop_end();
}
struct ubus_context *ubus_connect(const char *path)
{
struct ubus_context *ctx;
struct {
struct ubus_msghdr hdr;
struct blob_attr data;
} hdr;
struct blob_attr *buf;
if (!path)
path = UBUS_UNIX_SOCKET;
ctx = calloc(1, sizeof(*ctx));
if (!ctx)
goto error;
ctx->sock.fd = usock(USOCK_UNIX, path, NULL);
if (ctx->sock.fd < 0)
goto error_free;
ctx->sock.cb = ubus_handle_data;
if (read(ctx->sock.fd, &hdr, sizeof(hdr)) != sizeof(hdr))
goto error_close;
if (!ubus_validate_hdr(&hdr.hdr))
goto error_close;
if (hdr.hdr.type != UBUS_MSG_HELLO)
goto error_close;
buf = calloc(1, blob_raw_len(&hdr.data));
if (!buf)
goto error_close;
memcpy(buf, &hdr.data, sizeof(hdr.data));
if (read(ctx->sock.fd, blob_data(buf), blob_len(buf)) != blob_len(buf))
goto error_free_buf;
ctx->local_id = hdr.hdr.peer;
free(buf);
ctx->connection_lost = ubus_default_connection_lost;
INIT_LIST_HEAD(&ctx->requests);
avl_init(&ctx->objects, ubus_cmp_id, false, NULL);
if (!ctx->local_id)
goto error_close;
return ctx;
error_free_buf:
free(buf);
error_close:
close(ctx->sock.fd);
error_free:
free(ctx);
error:
return NULL;
}
void ubus_free(struct ubus_context *ctx)
{
close(ctx->sock.fd);
free(ctx);
}