libuv/src/unix/tcp.c
Ben Noordhuis 0971598d02 unix: fix EINPROGRESS busy loop
Don't make the event loop spin when connect() returns EINPROGRESS.

Test case:

  #include "uv.h"

  static void connect_cb(uv_connect_t* req, int status) {
    // ...
  }

  int main() {
    uv_tcp_t handle;
    uv_connect_t req;
    struct sockaddr_in addr;
    addr = uv_ip4_addr("8.8.8.8", 1234); // unreachable
    uv_tcp_init(uv_default_loop(), &handle);
    uv_tcp_connect(&req, (uv_stream_t*)&handle, addr, connect_cb);
    uv_run(uv_default_loop()); // busy loops until connection times out
    return 0;
  }

After EINPROGRESS, there are zero active handles and one active request. That
in turn makes uv__poll_timeout() believe that it should merely poll, not block,
in epoll() / kqueue() / port_getn().

Sidestep that by artificially starting the handle on connect() and stopping it
again once the TCP handshake completes / is rejected / times out.

It's a slightly hacky approach because I don't want to change the ABI of the
stable branch. I'll address it properly in the master branch.
2012-06-29 19:16:40 +02:00

370 lines
8.8 KiB
C

/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include "uv.h"
#include "internal.h"
#include <unistd.h>
#include <assert.h>
#include <errno.h>
int uv_tcp_init(uv_loop_t* loop, uv_tcp_t* tcp) {
uv__stream_init(loop, (uv_stream_t*)tcp, UV_TCP);
loop->counters.tcp_init++;
return 0;
}
static int maybe_new_socket(uv_tcp_t* handle, int domain, int flags) {
int sockfd;
if (handle->fd != -1)
return 0;
sockfd = uv__socket(domain, SOCK_STREAM, 0);
if (sockfd == -1)
return uv__set_sys_error(handle->loop, errno);
if (uv__stream_open((uv_stream_t*)handle, sockfd, flags)) {
close(sockfd);
return -1;
}
return 0;
}
static int uv__bind(uv_tcp_t* tcp,
int domain,
struct sockaddr* addr,
int addrsize) {
int saved_errno;
int status;
saved_errno = errno;
status = -1;
if (maybe_new_socket(tcp, domain, UV_STREAM_READABLE|UV_STREAM_WRITABLE))
return -1;
tcp->delayed_error = 0;
if (bind(tcp->fd, addr, addrsize) == -1) {
if (errno == EADDRINUSE) {
tcp->delayed_error = errno;
} else {
uv__set_sys_error(tcp->loop, errno);
goto out;
}
}
status = 0;
out:
errno = saved_errno;
return status;
}
static int uv__connect(uv_connect_t* req,
uv_tcp_t* handle,
struct sockaddr* addr,
socklen_t addrlen,
uv_connect_cb cb) {
int r;
assert(handle->type == UV_TCP);
if (handle->connect_req)
return uv__set_sys_error(handle->loop, EALREADY);
if (maybe_new_socket(handle,
addr->sa_family,
UV_STREAM_READABLE|UV_STREAM_WRITABLE)) {
return -1;
}
handle->delayed_error = 0;
do
r = connect(handle->fd, addr, addrlen);
while (r == -1 && errno == EINTR);
if (r == -1) {
if (errno == EINPROGRESS) {
/* Not an error. However, we need to keep the event loop from spinning
* while the connection is in progress. Artificially start the handle
* and stop it again in uv__stream_connect() in stream.c. Yes, it's a
* hack but there's no good alternative, the v0.8 ABI is frozen.
*/
if (!uv__is_active(handle)) {
handle->flags |= UV_TCP_CONNECTING;
uv__handle_start(handle);
}
}
else if (errno == ECONNREFUSED)
/* If we get a ECONNREFUSED wait until the next tick to report the
* error. Solaris wants to report immediately--other unixes want to
* wait.
*/
handle->delayed_error = errno;
else
return uv__set_sys_error(handle->loop, errno);
}
uv__req_init(handle->loop, req, UV_CONNECT);
req->cb = cb;
req->handle = (uv_stream_t*) handle;
ngx_queue_init(&req->queue);
handle->connect_req = req;
uv__io_start(handle->loop, &handle->write_watcher);
if (handle->delayed_error)
uv__io_feed(handle->loop, &handle->write_watcher, UV__IO_WRITE);
return 0;
}
int uv__tcp_bind(uv_tcp_t* handle, struct sockaddr_in addr) {
return uv__bind(handle,
AF_INET,
(struct sockaddr*)&addr,
sizeof(struct sockaddr_in));
}
int uv__tcp_bind6(uv_tcp_t* handle, struct sockaddr_in6 addr) {
return uv__bind(handle,
AF_INET6,
(struct sockaddr*)&addr,
sizeof(struct sockaddr_in6));
}
int uv_tcp_getsockname(uv_tcp_t* handle, struct sockaddr* name,
int* namelen) {
socklen_t socklen;
int saved_errno;
int rv = 0;
/* Don't clobber errno. */
saved_errno = errno;
if (handle->delayed_error) {
uv__set_sys_error(handle->loop, handle->delayed_error);
rv = -1;
goto out;
}
if (handle->fd < 0) {
uv__set_sys_error(handle->loop, EINVAL);
rv = -1;
goto out;
}
/* sizeof(socklen_t) != sizeof(int) on some systems. */
socklen = (socklen_t)*namelen;
if (getsockname(handle->fd, name, &socklen) == -1) {
uv__set_sys_error(handle->loop, errno);
rv = -1;
} else {
*namelen = (int)socklen;
}
out:
errno = saved_errno;
return rv;
}
int uv_tcp_getpeername(uv_tcp_t* handle, struct sockaddr* name,
int* namelen) {
socklen_t socklen;
int saved_errno;
int rv = 0;
/* Don't clobber errno. */
saved_errno = errno;
if (handle->delayed_error) {
uv__set_sys_error(handle->loop, handle->delayed_error);
rv = -1;
goto out;
}
if (handle->fd < 0) {
uv__set_sys_error(handle->loop, EINVAL);
rv = -1;
goto out;
}
/* sizeof(socklen_t) != sizeof(int) on some systems. */
socklen = (socklen_t)*namelen;
if (getpeername(handle->fd, name, &socklen) == -1) {
uv__set_sys_error(handle->loop, errno);
rv = -1;
} else {
*namelen = (int)socklen;
}
out:
errno = saved_errno;
return rv;
}
int uv_tcp_listen(uv_tcp_t* tcp, int backlog, uv_connection_cb cb) {
if (tcp->delayed_error)
return uv__set_sys_error(tcp->loop, tcp->delayed_error);
if (maybe_new_socket(tcp, AF_INET, UV_STREAM_READABLE))
return -1;
if (listen(tcp->fd, backlog))
return uv__set_sys_error(tcp->loop, errno);
tcp->connection_cb = cb;
/* Start listening for connections. */
uv__io_set(&tcp->read_watcher, uv__server_io, tcp->fd, UV__IO_READ);
uv__io_start(tcp->loop, &tcp->read_watcher);
return 0;
}
int uv__tcp_connect(uv_connect_t* req,
uv_tcp_t* handle,
struct sockaddr_in addr,
uv_connect_cb cb) {
int saved_errno;
int status;
saved_errno = errno;
status = uv__connect(req, handle, (struct sockaddr*)&addr, sizeof addr, cb);
errno = saved_errno;
return status;
}
int uv__tcp_connect6(uv_connect_t* req,
uv_tcp_t* handle,
struct sockaddr_in6 addr,
uv_connect_cb cb) {
int saved_errno;
int status;
saved_errno = errno;
status = uv__connect(req, handle, (struct sockaddr*)&addr, sizeof addr, cb);
errno = saved_errno;
return status;
}
int uv__tcp_nodelay(uv_tcp_t* handle, int enable) {
if (setsockopt(handle->fd,
IPPROTO_TCP,
TCP_NODELAY,
&enable,
sizeof enable) == -1) {
uv__set_sys_error(handle->loop, errno);
return -1;
}
return 0;
}
int uv__tcp_keepalive(uv_tcp_t* handle, int enable, unsigned int delay) {
if (setsockopt(handle->fd,
SOL_SOCKET,
SO_KEEPALIVE,
&enable,
sizeof enable) == -1) {
uv__set_sys_error(handle->loop, errno);
return -1;
}
#ifdef TCP_KEEPIDLE
if (enable && setsockopt(handle->fd,
IPPROTO_TCP,
TCP_KEEPIDLE,
&delay,
sizeof delay) == -1) {
uv__set_sys_error(handle->loop, errno);
return -1;
}
#endif
#ifdef TCP_KEEPALIVE
if (enable && setsockopt(handle->fd,
IPPROTO_TCP,
TCP_KEEPALIVE,
&delay,
sizeof delay) == -1) {
uv__set_sys_error(handle->loop, errno);
return -1;
}
#endif
return 0;
}
int uv_tcp_nodelay(uv_tcp_t* handle, int enable) {
if (handle->fd != -1 && uv__tcp_nodelay(handle, enable))
return -1;
if (enable)
handle->flags |= UV_TCP_NODELAY;
else
handle->flags &= ~UV_TCP_NODELAY;
return 0;
}
int uv_tcp_keepalive(uv_tcp_t* handle, int enable, unsigned int delay) {
if (handle->fd != -1 && uv__tcp_keepalive(handle, enable, delay))
return -1;
if (enable)
handle->flags |= UV_TCP_KEEPALIVE;
else
handle->flags &= ~UV_TCP_KEEPALIVE;
/* TODO Store delay if handle->fd == -1 but don't want to enlarge
* uv_tcp_t with an int that's almost never used...
*/
return 0;
}
int uv_tcp_simultaneous_accepts(uv_tcp_t* handle, int enable) {
return 0;
}