int virtual_stream_read(Channel * c, char * token, char * id, size_t size) {
int err = 0;
StreamClient * client = find_client(id, c);
if (client == NULL) err = errno;
if (!err && (client->stream->access & VS_ENABLE_REMOTE_READ) == 0) err = ERR_UNSUPPORTED;
if (err == 0) {
VirtualStream * stream = client->stream;
if (client->pos == stream->pos && !stream->eos_inp) {
ReadRequest * r = (ReadRequest *)loc_alloc_zero(sizeof(ReadRequest));
list_init(&r->link_client);
r->client = client;
r->size = size;
strlcpy(r->token, token, sizeof(r->token));
list_add_last(&r->link_client, &client->read_requests);
}
else {
assert(list_is_empty(&client->read_requests));
assert(client->channel == c);
send_read_reply(client, token, size);
advance_stream_buffer(stream);
}
}
else errno = err;
return err == 0 ? 0 : -1;
}
int virtual_stream_add_data(VirtualStream * stream, char * buf, size_t buf_size, size_t * data_size, int eos) {
int err = 0;
assert(stream->magic == STREAM_MAGIC);
if (stream->eos_inp) err = ERR_EOF;
if (!err) {
size_t len = (stream->buf_out + stream->buf_len - stream->buf_inp - 1) % stream->buf_len;
assert(len < stream->buf_len);
if (buf_size < len) len = buf_size;
if (stream->buf_inp + len <= stream->buf_len) {
memcpy(stream->buf + stream->buf_inp, buf, len);
}
else {
size_t x = stream->buf_len - stream->buf_inp;
size_t y = len - x;
memcpy(stream->buf + stream->buf_inp, buf, x);
memcpy(stream->buf, buf + x, y);
}
stream->buf_inp = (stream->buf_inp + len) % stream->buf_len;
stream->pos += len;
*data_size = len;
if (eos && buf_size == len) stream->eos_inp = 1;
}
if (stream->access & VS_ENABLE_REMOTE_READ) {
if (!err && (stream->eos_inp || *data_size > 0)) {
LINK * l;
for (l = stream->clients.next; l != &stream->clients; l = l->next) {
StreamClient * client = stream2client(l);
while (!list_is_empty(&client->read_requests) && (client->pos < stream->pos || stream->eos_inp)) {
ReadRequest * r = client2read_request(client->read_requests.next);
list_remove(&r->link_client);
send_read_reply(client, r->token, r->size);
loc_free(r);
}
}
advance_stream_buffer(stream);
}
}
else if (!stream->data_available_posted) {
post_event(notify_data_available, stream);
stream->data_available_posted = 1;
}
errno = err;
return err ? -1 : 0;
}
static void command_read(char * token, Channel * c) {
char id[256];
size_t size = 0;
StreamClient * client = NULL;
int err = 0;
json_read_string(&c->inp, id, sizeof(id));
if (read_stream(&c->inp) != 0) exception(ERR_JSON_SYNTAX);
size = json_read_ulong(&c->inp);
if (read_stream(&c->inp) != 0) exception(ERR_JSON_SYNTAX);
if (read_stream(&c->inp) != MARKER_EOM) exception(ERR_JSON_SYNTAX);
client = find_client(id, c);
if (client == NULL) err = errno;
if (!err && (client->stream->access & VS_ENABLE_REMOTE_READ) == 0) err = ERR_UNSUPPORTED;
if (err == 0) {
VirtualStream * stream = client->stream;
if (client->pos == stream->pos && !stream->eos) {
ReadRequest * r = loc_alloc_zero(sizeof(ReadRequest));
list_init(&r->link_client);
r->client = client;
r->size = size;
strncpy(r->token, token, sizeof(r->token) - 1);
list_add_last(&r->link_client, &client->read_requests);
}
else {
assert(list_is_empty(&client->read_requests));
assert(client->channel == c);
send_read_reply(client, token, size);
advance_stream_buffer(stream);
}
}
else {
write_stringz(&c->out, "R");
write_stringz(&c->out, token);
write_stringz(&c->out, "null");
write_errno(&c->out, err);
json_write_long(&c->out, 0);
write_stream(&c->out, 0);
json_write_boolean(&c->out, 0);
write_stream(&c->out, 0);
write_stream(&c->out, MARKER_EOM);
}
}
