/* 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 #include #include #include #include #include #include #include #include #include #include /* IOV_MAX */ #if defined(__APPLE__) # include # include # include /* Forward declaration */ typedef struct uv__stream_select_s uv__stream_select_t; struct uv__stream_select_s { uv_stream_t* stream; uv_thread_t thread; uv_sem_t close_sem; uv_sem_t async_sem; uv_async_t async; int events; int fake_fd; int int_fd; int fd; }; #endif /* defined(__APPLE__) */ static void uv__stream_connect(uv_stream_t*); static void uv__write(uv_stream_t* stream); static void uv__read(uv_stream_t* stream); static void uv__stream_io(uv_loop_t* loop, uv__io_t* w, unsigned int events); static size_t uv__write_req_size(uv_write_t* req); /* Used by the accept() EMFILE party trick. */ static int uv__open_cloexec(const char* path, int flags) { int err; int fd; #if defined(__linux__) fd = open(path, flags | UV__O_CLOEXEC); if (fd != -1) return fd; if (errno != EINVAL) return -errno; /* O_CLOEXEC not supported. */ #endif fd = open(path, flags); if (fd == -1) return -errno; err = uv__cloexec(fd, 1); if (err) { uv__close(fd); return err; } return fd; } static size_t uv_count_bufs(const uv_buf_t bufs[], unsigned int nbufs) { unsigned int i; size_t bytes; bytes = 0; for (i = 0; i < nbufs; i++) bytes += bufs[i].len; return bytes; } void uv__stream_init(uv_loop_t* loop, uv_stream_t* stream, uv_handle_type type) { int err; uv__handle_init(loop, (uv_handle_t*)stream, type); stream->read_cb = NULL; stream->read2_cb = NULL; stream->alloc_cb = NULL; stream->close_cb = NULL; stream->connection_cb = NULL; stream->connect_req = NULL; stream->shutdown_req = NULL; stream->accepted_fd = -1; stream->delayed_error = 0; QUEUE_INIT(&stream->write_queue); QUEUE_INIT(&stream->write_completed_queue); stream->write_queue_size = 0; if (loop->emfile_fd == -1) { err = uv__open_cloexec("/", O_RDONLY); if (err >= 0) loop->emfile_fd = err; } #if defined(__APPLE__) stream->select = NULL; #endif /* defined(__APPLE_) */ uv__io_init(&stream->io_watcher, uv__stream_io, -1); } #if defined(__APPLE__) static void uv__stream_osx_select(void* arg) { uv_stream_t* stream; uv__stream_select_t* s; char buf[1024]; fd_set sread; fd_set swrite; int events; int fd; int r; int max_fd; stream = arg; s = stream->select; fd = s->fd; if (fd > s->int_fd) max_fd = fd; else max_fd = s->int_fd; while (1) { /* Terminate on semaphore */ if (uv_sem_trywait(&s->close_sem) == 0) break; /* Watch fd using select(2) */ FD_ZERO(&sread); FD_ZERO(&swrite); if (uv_is_readable(stream)) FD_SET(fd, &sread); if (uv_is_writable(stream)) FD_SET(fd, &swrite); FD_SET(s->int_fd, &sread); /* Wait indefinitely for fd events */ r = select(max_fd + 1, &sread, &swrite, NULL, NULL); if (r == -1) { if (errno == EINTR) continue; /* XXX: Possible?! */ abort(); } /* Ignore timeouts */ if (r == 0) continue; /* Empty socketpair's buffer in case of interruption */ if (FD_ISSET(s->int_fd, &sread)) while (1) { r = read(s->int_fd, buf, sizeof(buf)); if (r == sizeof(buf)) continue; if (r != -1) break; if (errno == EAGAIN || errno == EWOULDBLOCK) break; if (errno == EINTR) continue; abort(); } /* Handle events */ events = 0; if (FD_ISSET(fd, &sread)) events |= UV__POLLIN; if (FD_ISSET(fd, &swrite)) events |= UV__POLLOUT; assert(events != 0 || FD_ISSET(s->int_fd, &sread)); if (events != 0) { ACCESS_ONCE(int, s->events) = events; uv_async_send(&s->async); uv_sem_wait(&s->async_sem); /* Should be processed at this stage */ assert((s->events == 0) || (stream->flags & UV_CLOSING)); } } } static void uv__stream_osx_interrupt_select(uv_stream_t* stream) { /* Notify select() thread about state change */ uv__stream_select_t* s; int r; s = stream->select; /* Interrupt select() loop * NOTE: fake_fd and int_fd are socketpair(), thus writing to one will * emit read event on other side */ do r = write(s->fake_fd, "x", 1); while (r == -1 && errno == EINTR); assert(r == 1); } static void uv__stream_osx_select_cb(uv_async_t* handle, int status) { uv__stream_select_t* s; uv_stream_t* stream; int events; s = container_of(handle, uv__stream_select_t, async); stream = s->stream; /* Get and reset stream's events */ events = s->events; ACCESS_ONCE(int, s->events) = 0; uv_sem_post(&s->async_sem); assert(events != 0); assert(events == (events & (UV__POLLIN | UV__POLLOUT))); /* Invoke callback on event-loop */ if ((events & UV__POLLIN) && uv__io_active(&stream->io_watcher, UV__POLLIN)) uv__stream_io(stream->loop, &stream->io_watcher, UV__POLLIN); if ((events & UV__POLLOUT) && uv__io_active(&stream->io_watcher, UV__POLLOUT)) uv__stream_io(stream->loop, &stream->io_watcher, UV__POLLOUT); } static void uv__stream_osx_cb_close(uv_handle_t* async) { uv__stream_select_t* s; s = container_of(async, uv__stream_select_t, async); free(s); } int uv__stream_try_select(uv_stream_t* stream, int* fd) { /* * kqueue doesn't work with some files from /dev mount on osx. * select(2) in separate thread for those fds */ struct kevent filter[1]; struct kevent events[1]; struct timespec timeout; uv__stream_select_t* s; int fds[2]; int err; int ret; int kq; kq = kqueue(); if (kq == -1) { fprintf(stderr, "(libuv) Failed to create kqueue (%d)\n", errno); return -errno; } EV_SET(&filter[0], *fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0, 0); /* Use small timeout, because we only want to capture EINVALs */ timeout.tv_sec = 0; timeout.tv_nsec = 1; ret = kevent(kq, filter, 1, events, 1, &timeout); uv__close(kq); if (ret == -1) return -errno; if (ret == 0 || (events[0].flags & EV_ERROR) == 0 || events[0].data != EINVAL) return 0; /* At this point we definitely know that this fd won't work with kqueue */ s = malloc(sizeof(*s)); if (s == NULL) return -ENOMEM; s->events = 0; s->fd = *fd; err = uv_async_init(stream->loop, &s->async, uv__stream_osx_select_cb); if (err) { free(s); return err; } s->async.flags |= UV__HANDLE_INTERNAL; uv__handle_unref(&s->async); if (uv_sem_init(&s->close_sem, 0)) goto fatal1; if (uv_sem_init(&s->async_sem, 0)) goto fatal2; /* Create fds for io watcher and to interrupt the select() loop. */ if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds)) goto fatal3; s->fake_fd = fds[0]; s->int_fd = fds[1]; if (uv_thread_create(&s->thread, uv__stream_osx_select, stream)) goto fatal4; s->stream = stream; stream->select = s; *fd = s->fake_fd; return 0; fatal4: uv__close(s->fake_fd); uv__close(s->int_fd); s->fake_fd = -1; s->int_fd = -1; fatal3: uv_sem_destroy(&s->async_sem); fatal2: uv_sem_destroy(&s->close_sem); fatal1: uv_close((uv_handle_t*) &s->async, uv__stream_osx_cb_close); return -errno; } #endif /* defined(__APPLE__) */ int uv__stream_open(uv_stream_t* stream, int fd, int flags) { assert(fd >= 0); stream->flags |= flags; if (stream->type == UV_TCP) { if ((stream->flags & UV_TCP_NODELAY) && uv__tcp_nodelay(fd, 1)) return -errno; /* TODO Use delay the user passed in. */ if ((stream->flags & UV_TCP_KEEPALIVE) && uv__tcp_keepalive(fd, 1, 60)) return -errno; } stream->io_watcher.fd = fd; return 0; } void uv__stream_destroy(uv_stream_t* stream) { uv_write_t* req; QUEUE* q; assert(!uv__io_active(&stream->io_watcher, UV__POLLIN | UV__POLLOUT)); assert(stream->flags & UV_CLOSED); if (stream->connect_req) { uv__req_unregister(stream->loop, stream->connect_req); stream->connect_req->cb(stream->connect_req, -ECANCELED); stream->connect_req = NULL; } while (!QUEUE_EMPTY(&stream->write_queue)) { q = QUEUE_HEAD(&stream->write_queue); QUEUE_REMOVE(q); req = QUEUE_DATA(q, uv_write_t, queue); uv__req_unregister(stream->loop, req); if (req->bufs != req->bufsml) free(req->bufs); req->bufs = NULL; if (req->cb != NULL) req->cb(req, -ECANCELED); } while (!QUEUE_EMPTY(&stream->write_completed_queue)) { q = QUEUE_HEAD(&stream->write_completed_queue); QUEUE_REMOVE(q); req = QUEUE_DATA(q, uv_write_t, queue); uv__req_unregister(stream->loop, req); if (req->bufs != NULL) { stream->write_queue_size -= uv__write_req_size(req); if (req->bufs != req->bufsml) free(req->bufs); req->bufs = NULL; } if (req->cb) req->cb(req, req->error); } if (stream->shutdown_req) { /* The ECANCELED error code is a lie, the shutdown(2) syscall is a * fait accompli at this point. Maybe we should revisit this in v0.11. * A possible reason for leaving it unchanged is that it informs the * callee that the handle has been destroyed. */ uv__req_unregister(stream->loop, stream->shutdown_req); stream->shutdown_req->cb(stream->shutdown_req, -ECANCELED); stream->shutdown_req = NULL; } } /* Implements a best effort approach to mitigating accept() EMFILE errors. * We have a spare file descriptor stashed away that we close to get below * the EMFILE limit. Next, we accept all pending connections and close them * immediately to signal the clients that we're overloaded - and we are, but * we still keep on trucking. * * There is one caveat: it's not reliable in a multi-threaded environment. * The file descriptor limit is per process. Our party trick fails if another * thread opens a file or creates a socket in the time window between us * calling close() and accept(). */ static int uv__emfile_trick(uv_loop_t* loop, int accept_fd) { int fd; if (loop->emfile_fd == -1) return -EMFILE; uv__close(loop->emfile_fd); for (;;) { fd = uv__accept(accept_fd); if (fd != -1) { uv__close(fd); continue; } if (errno == EINTR) continue; SAVE_ERRNO(loop->emfile_fd = uv__open_cloexec("/", O_RDONLY)); return -errno; } } #if defined(UV_HAVE_KQUEUE) # define UV_DEC_BACKLOG(w) w->rcount--; #else # define UV_DEC_BACKLOG(w) /* no-op */ #endif /* defined(UV_HAVE_KQUEUE) */ void uv__server_io(uv_loop_t* loop, uv__io_t* w, unsigned int events) { uv_stream_t* stream; int err; stream = container_of(w, uv_stream_t, io_watcher); assert(events == UV__POLLIN); assert(stream->accepted_fd == -1); assert(!(stream->flags & UV_CLOSING)); uv__io_start(stream->loop, &stream->io_watcher, UV__POLLIN); /* connection_cb can close the server socket while we're * in the loop so check it on each iteration. */ while (uv__stream_fd(stream) != -1) { assert(stream->accepted_fd == -1); #if defined(UV_HAVE_KQUEUE) if (w->rcount <= 0) return; #endif /* defined(UV_HAVE_KQUEUE) */ err = uv__accept(uv__stream_fd(stream)); if (err < 0) { if (err == -EAGAIN || err == -EWOULDBLOCK) return; /* Not an error. */ if (err == -ECONNABORTED) continue; /* Ignore. Nothing we can do about that. */ if (err == -EMFILE || err == -ENFILE) { err = uv__emfile_trick(loop, uv__stream_fd(stream)); if (err == -EAGAIN || err == -EWOULDBLOCK) break; } stream->connection_cb(stream, err); continue; } UV_DEC_BACKLOG(w) stream->accepted_fd = err; stream->connection_cb(stream, 0); if (stream->accepted_fd != -1) { /* The user hasn't yet accepted called uv_accept() */ uv__io_stop(loop, &stream->io_watcher, UV__POLLIN); return; } if (stream->type == UV_TCP && (stream->flags & UV_TCP_SINGLE_ACCEPT)) { /* Give other processes a chance to accept connections. */ struct timespec timeout = { 0, 1 }; nanosleep(&timeout, NULL); } } } #undef UV_DEC_BACKLOG int uv_accept(uv_stream_t* server, uv_stream_t* client) { int err; /* TODO document this */ assert(server->loop == client->loop); if (server->accepted_fd == -1) return -EAGAIN; switch (client->type) { case UV_NAMED_PIPE: case UV_TCP: err = uv__stream_open(client, server->accepted_fd, UV_STREAM_READABLE | UV_STREAM_WRITABLE); if (err) { /* TODO handle error */ uv__close(server->accepted_fd); server->accepted_fd = -1; return err; } break; case UV_UDP: err = uv_udp_open((uv_udp_t*) client, server->accepted_fd); if (err) { uv__close(server->accepted_fd); server->accepted_fd = -1; return err; } break; default: assert(0); } uv__io_start(server->loop, &server->io_watcher, UV__POLLIN); server->accepted_fd = -1; return 0; } int uv_listen(uv_stream_t* stream, int backlog, uv_connection_cb cb) { int err; err = -EINVAL; switch (stream->type) { case UV_TCP: err = uv_tcp_listen((uv_tcp_t*)stream, backlog, cb); break; case UV_NAMED_PIPE: err = uv_pipe_listen((uv_pipe_t*)stream, backlog, cb); break; default: assert(0); } if (err == 0) uv__handle_start(stream); return err; } static void uv__drain(uv_stream_t* stream) { uv_shutdown_t* req; int err; assert(QUEUE_EMPTY(&stream->write_queue)); uv__io_stop(stream->loop, &stream->io_watcher, UV__POLLOUT); /* Shutdown? */ if ((stream->flags & UV_STREAM_SHUTTING) && !(stream->flags & UV_CLOSING) && !(stream->flags & UV_STREAM_SHUT)) { assert(stream->shutdown_req); req = stream->shutdown_req; stream->shutdown_req = NULL; stream->flags &= ~UV_STREAM_SHUTTING; uv__req_unregister(stream->loop, req); err = 0; if (shutdown(uv__stream_fd(stream), SHUT_WR)) err = -errno; if (err == 0) stream->flags |= UV_STREAM_SHUT; if (req->cb != NULL) req->cb(req, err); } } static size_t uv__write_req_size(uv_write_t* req) { size_t size; assert(req->bufs != NULL); size = uv_count_bufs(req->bufs + req->write_index, req->nbufs - req->write_index); assert(req->handle->write_queue_size >= size); return size; } static void uv__write_req_finish(uv_write_t* req) { uv_stream_t* stream = req->handle; /* Pop the req off tcp->write_queue. */ QUEUE_REMOVE(&req->queue); /* Only free when there was no error. On error, we touch up write_queue_size * right before making the callback. The reason we don't do that right away * is that a write_queue_size > 0 is our only way to signal to the user that * he should stop writing - which he should if we got an error. Something to * revisit in future revisions of the libuv API. */ if (req->error == 0) { if (req->bufs != req->bufsml) free(req->bufs); req->bufs = NULL; } /* Add it to the write_completed_queue where it will have its * callback called in the near future. */ QUEUE_INSERT_TAIL(&stream->write_completed_queue, &req->queue); uv__io_feed(stream->loop, &stream->io_watcher); } static int uv__handle_fd(uv_handle_t* handle) { switch (handle->type) { case UV_NAMED_PIPE: case UV_TCP: return ((uv_stream_t*) handle)->io_watcher.fd; case UV_UDP: return ((uv_udp_t*) handle)->io_watcher.fd; default: return -1; } } static int uv__getiovmax() { #if defined(IOV_MAX) return IOV_MAX; #elif defined(_SC_IOV_MAX) static int iovmax = -1; if (iovmax == -1) iovmax = sysconf(_SC_IOV_MAX); return iovmax; #else return 1024; #endif } static void uv__write(uv_stream_t* stream) { struct iovec* iov; QUEUE* q; uv_write_t* req; int iovmax; int iovcnt; ssize_t n; start: assert(uv__stream_fd(stream) >= 0); if (QUEUE_EMPTY(&stream->write_queue)) return; q = QUEUE_HEAD(&stream->write_queue); req = QUEUE_DATA(q, uv_write_t, queue); assert(req->handle == stream); /* * Cast to iovec. We had to have our own uv_buf_t instead of iovec * because Windows's WSABUF is not an iovec. */ assert(sizeof(uv_buf_t) == sizeof(struct iovec)); iov = (struct iovec*) &(req->bufs[req->write_index]); iovcnt = req->nbufs - req->write_index; iovmax = uv__getiovmax(); /* Limit iov count to avoid EINVALs from writev() */ if (iovcnt > iovmax) iovcnt = iovmax; /* * Now do the actual writev. Note that we've been updating the pointers * inside the iov each time we write. So there is no need to offset it. */ if (req->send_handle) { struct msghdr msg; char scratch[64]; struct cmsghdr *cmsg; int fd_to_send = uv__handle_fd((uv_handle_t*) req->send_handle); assert(fd_to_send >= 0); msg.msg_name = NULL; msg.msg_namelen = 0; msg.msg_iov = iov; msg.msg_iovlen = iovcnt; msg.msg_flags = 0; msg.msg_control = (void*) scratch; msg.msg_controllen = CMSG_LEN(sizeof(fd_to_send)); cmsg = CMSG_FIRSTHDR(&msg); cmsg->cmsg_level = SOL_SOCKET; cmsg->cmsg_type = SCM_RIGHTS; cmsg->cmsg_len = msg.msg_controllen; /* silence aliasing warning */ { void* pv = CMSG_DATA(cmsg); int* pi = pv; *pi = fd_to_send; } do { n = sendmsg(uv__stream_fd(stream), &msg, 0); } while (n == -1 && errno == EINTR); } else { do { if (iovcnt == 1) { n = write(uv__stream_fd(stream), iov[0].iov_base, iov[0].iov_len); } else { n = writev(uv__stream_fd(stream), iov, iovcnt); } } while (n == -1 && errno == EINTR); } if (n < 0) { if (errno != EAGAIN && errno != EWOULDBLOCK) { /* Error */ req->error = -errno; uv__write_req_finish(req); uv__io_stop(stream->loop, &stream->io_watcher, UV__POLLOUT); if (!uv__io_active(&stream->io_watcher, UV__POLLIN)) uv__handle_stop(stream); return; } else if (stream->flags & UV_STREAM_BLOCKING) { /* If this is a blocking stream, try again. */ goto start; } } else { /* Successful write */ while (n >= 0) { uv_buf_t* buf = &(req->bufs[req->write_index]); size_t len = buf->len; assert(req->write_index < req->nbufs); if ((size_t)n < len) { buf->base += n; buf->len -= n; stream->write_queue_size -= n; n = 0; /* There is more to write. */ if (stream->flags & UV_STREAM_BLOCKING) { /* * If we're blocking then we should not be enabling the write * watcher - instead we need to try again. */ goto start; } else { /* Break loop and ensure the watcher is pending. */ break; } } else { /* Finished writing the buf at index req->write_index. */ req->write_index++; assert((size_t)n >= len); n -= len; assert(stream->write_queue_size >= len); stream->write_queue_size -= len; if (req->write_index == req->nbufs) { /* Then we're done! */ assert(n == 0); uv__write_req_finish(req); /* TODO: start trying to write the next request. */ return; } } } } /* Either we've counted n down to zero or we've got EAGAIN. */ assert(n == 0 || n == -1); /* Only non-blocking streams should use the write_watcher. */ assert(!(stream->flags & UV_STREAM_BLOCKING)); /* We're not done. */ uv__io_start(stream->loop, &stream->io_watcher, UV__POLLOUT); } static void uv__write_callbacks(uv_stream_t* stream) { uv_write_t* req; QUEUE* q; while (!QUEUE_EMPTY(&stream->write_completed_queue)) { /* Pop a req off write_completed_queue. */ q = QUEUE_HEAD(&stream->write_completed_queue); req = QUEUE_DATA(q, uv_write_t, queue); QUEUE_REMOVE(q); uv__req_unregister(stream->loop, req); if (req->bufs != NULL) { stream->write_queue_size -= uv__write_req_size(req); if (req->bufs != req->bufsml) free(req->bufs); req->bufs = NULL; } /* NOTE: call callback AFTER freeing the request data. */ if (req->cb) req->cb(req, req->error); } assert(QUEUE_EMPTY(&stream->write_completed_queue)); /* Write queue drained. */ if (QUEUE_EMPTY(&stream->write_queue)) uv__drain(stream); } static uv_handle_type uv__handle_type(int fd) { struct sockaddr_storage ss; socklen_t len; int type; memset(&ss, 0, sizeof(ss)); len = sizeof(ss); if (getsockname(fd, (struct sockaddr*)&ss, &len)) return UV_UNKNOWN_HANDLE; len = sizeof type; if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &type, &len)) return UV_UNKNOWN_HANDLE; if (type == SOCK_STREAM) { switch (ss.ss_family) { case AF_UNIX: return UV_NAMED_PIPE; case AF_INET: case AF_INET6: return UV_TCP; } } if (type == SOCK_DGRAM && (ss.ss_family == AF_INET || ss.ss_family == AF_INET6)) return UV_UDP; return UV_UNKNOWN_HANDLE; } static void uv__stream_read_cb(uv_stream_t* stream, int status, const uv_buf_t* buf, uv_handle_type type) { if (stream->read_cb != NULL) stream->read_cb(stream, status, buf); else stream->read2_cb((uv_pipe_t*) stream, status, buf, type); } static void uv__stream_eof(uv_stream_t* stream, const uv_buf_t* buf) { stream->flags |= UV_STREAM_READ_EOF; uv__io_stop(stream->loop, &stream->io_watcher, UV__POLLIN); if (!uv__io_active(&stream->io_watcher, UV__POLLOUT)) uv__handle_stop(stream); uv__stream_read_cb(stream, UV_EOF, buf, UV_UNKNOWN_HANDLE); } static void uv__read(uv_stream_t* stream) { uv_buf_t buf; ssize_t nread; struct msghdr msg; struct cmsghdr* cmsg; char cmsg_space[64]; int count; stream->flags &= ~UV_STREAM_READ_PARTIAL; /* Prevent loop starvation when the data comes in as fast as (or faster than) * we can read it. XXX Need to rearm fd if we switch to edge-triggered I/O. */ count = 32; /* XXX: Maybe instead of having UV_STREAM_READING we just test if * tcp->read_cb is NULL or not? */ while ((stream->read_cb || stream->read2_cb) && (stream->flags & UV_STREAM_READING) && (count-- > 0)) { assert(stream->alloc_cb != NULL); stream->alloc_cb((uv_handle_t*)stream, 64 * 1024, &buf); if (buf.len == 0) { /* User indicates it can't or won't handle the read. */ uv__stream_read_cb(stream, UV_ENOBUFS, &buf, UV_UNKNOWN_HANDLE); return; } assert(buf.base != NULL); assert(uv__stream_fd(stream) >= 0); if (stream->read_cb) { do { nread = read(uv__stream_fd(stream), buf.base, buf.len); } while (nread < 0 && errno == EINTR); } else { assert(stream->read2_cb); /* read2_cb uses recvmsg */ msg.msg_flags = 0; msg.msg_iov = (struct iovec*) &buf; msg.msg_iovlen = 1; msg.msg_name = NULL; msg.msg_namelen = 0; /* Set up to receive a descriptor even if one isn't in the message */ msg.msg_controllen = 64; msg.msg_control = (void*) cmsg_space; do { nread = recvmsg(uv__stream_fd(stream), &msg, 0); } while (nread < 0 && errno == EINTR); } if (nread < 0) { /* Error */ if (errno == EAGAIN || errno == EWOULDBLOCK) { /* Wait for the next one. */ if (stream->flags & UV_STREAM_READING) { uv__io_start(stream->loop, &stream->io_watcher, UV__POLLIN); } uv__stream_read_cb(stream, 0, &buf, UV_UNKNOWN_HANDLE); } else { /* Error. User should call uv_close(). */ uv__stream_read_cb(stream, -errno, &buf, UV_UNKNOWN_HANDLE); assert(!uv__io_active(&stream->io_watcher, UV__POLLIN) && "stream->read_cb(status=-1) did not call uv_close()"); } return; } else if (nread == 0) { uv__stream_eof(stream, &buf); return; } else { /* Successful read */ ssize_t buflen = buf.len; if (stream->read_cb) { stream->read_cb(stream, nread, &buf); } else { assert(stream->read2_cb); /* * XXX: Some implementations can send multiple file descriptors in a * single message. We should be using CMSG_NXTHDR() to walk the * chain to get at them all. This would require changing the API to * hand these back up the caller, is a pain. */ for (cmsg = CMSG_FIRSTHDR(&msg); msg.msg_controllen > 0 && cmsg != NULL; cmsg = CMSG_NXTHDR(&msg, cmsg)) { if (cmsg->cmsg_type == SCM_RIGHTS) { if (stream->accepted_fd != -1) { fprintf(stderr, "(libuv) ignoring extra FD received\n"); } /* silence aliasing warning */ { void* pv = CMSG_DATA(cmsg); int* pi = pv; stream->accepted_fd = *pi; } } else { fprintf(stderr, "ignoring non-SCM_RIGHTS ancillary data: %d\n", cmsg->cmsg_type); } } if (stream->accepted_fd >= 0) { stream->read2_cb((uv_pipe_t*) stream, nread, &buf, uv__handle_type(stream->accepted_fd)); } else { stream->read2_cb((uv_pipe_t*) stream, nread, &buf, UV_UNKNOWN_HANDLE); } } /* Return if we didn't fill the buffer, there is no more data to read. */ if (nread < buflen) { stream->flags |= UV_STREAM_READ_PARTIAL; return; } } } } int uv_shutdown(uv_shutdown_t* req, uv_stream_t* stream, uv_shutdown_cb cb) { assert((stream->type == UV_TCP || stream->type == UV_NAMED_PIPE) && "uv_shutdown (unix) only supports uv_handle_t right now"); if (!(stream->flags & UV_STREAM_WRITABLE) || stream->flags & UV_STREAM_SHUT || stream->flags & UV_CLOSED || stream->flags & UV_CLOSING) { return -ENOTCONN; } assert(uv__stream_fd(stream) >= 0); /* Initialize request */ uv__req_init(stream->loop, req, UV_SHUTDOWN); req->handle = stream; req->cb = cb; stream->shutdown_req = req; stream->flags |= UV_STREAM_SHUTTING; uv__io_start(stream->loop, &stream->io_watcher, UV__POLLOUT); return 0; } static void uv__stream_io(uv_loop_t* loop, uv__io_t* w, unsigned int events) { uv_stream_t* stream; stream = container_of(w, uv_stream_t, io_watcher); assert(stream->type == UV_TCP || stream->type == UV_NAMED_PIPE || stream->type == UV_TTY); assert(!(stream->flags & UV_CLOSING)); if (stream->connect_req) { uv__stream_connect(stream); return; } assert(uv__stream_fd(stream) >= 0); /* Ignore POLLHUP here. Even it it's set, there may still be data to read. */ if (events & (UV__POLLIN | UV__POLLERR)) uv__read(stream); if (uv__stream_fd(stream) == -1) return; /* read_cb closed stream. */ /* Short-circuit iff POLLHUP is set, the user is still interested in read * events and uv__read() reported a partial read but not EOF. If the EOF * flag is set, uv__read() called read_cb with err=UV_EOF and we don't * have to do anything. If the partial read flag is not set, we can't * report the EOF yet because there is still data to read. */ if ((events & UV__POLLHUP) && (stream->flags & UV_STREAM_READING) && (stream->flags & UV_STREAM_READ_PARTIAL) && !(stream->flags & UV_STREAM_READ_EOF)) { uv_buf_t buf = { NULL, 0 }; uv__stream_eof(stream, &buf); } if (uv__stream_fd(stream) == -1) return; /* read_cb closed stream. */ if (events & (UV__POLLOUT | UV__POLLERR | UV__POLLHUP)) { uv__write(stream); uv__write_callbacks(stream); } } /** * We get called here from directly following a call to connect(2). * In order to determine if we've errored out or succeeded must call * getsockopt. */ static void uv__stream_connect(uv_stream_t* stream) { int error; uv_connect_t* req = stream->connect_req; socklen_t errorsize = sizeof(int); assert(stream->type == UV_TCP || stream->type == UV_NAMED_PIPE); assert(req); if (stream->delayed_error) { /* To smooth over the differences between unixes errors that * were reported synchronously on the first connect can be delayed * until the next tick--which is now. */ error = stream->delayed_error; stream->delayed_error = 0; } else { /* Normal situation: we need to get the socket error from the kernel. */ assert(uv__stream_fd(stream) >= 0); getsockopt(uv__stream_fd(stream), SOL_SOCKET, SO_ERROR, &error, &errorsize); error = -error; } if (error == -EINPROGRESS) return; stream->connect_req = NULL; uv__req_unregister(stream->loop, req); uv__io_stop(stream->loop, &stream->io_watcher, UV__POLLOUT); if (req->cb) req->cb(req, error); } int uv_write2(uv_write_t* req, uv_stream_t* stream, const uv_buf_t bufs[], unsigned int nbufs, uv_stream_t* send_handle, uv_write_cb cb) { int empty_queue; assert(nbufs > 0); assert((stream->type == UV_TCP || stream->type == UV_NAMED_PIPE || stream->type == UV_TTY) && "uv_write (unix) does not yet support other types of streams"); if (uv__stream_fd(stream) < 0) return -EBADF; if (send_handle) { if (stream->type != UV_NAMED_PIPE || !((uv_pipe_t*)stream)->ipc) return -EINVAL; /* XXX We abuse uv_write2() to send over UDP handles to child processes. * Don't call uv__stream_fd() on those handles, it's a macro that on OS X * evaluates to a function that operates on a uv_stream_t with a couple of * OS X specific fields. On other Unices it does (handle)->io_watcher.fd, * which works but only by accident. */ if (uv__handle_fd((uv_handle_t*) send_handle) < 0) return -EBADF; } /* It's legal for write_queue_size > 0 even when the write_queue is empty; * it means there are error-state requests in the write_completed_queue that * will touch up write_queue_size later, see also uv__write_req_finish(). * We chould check that write_queue is empty instead but that implies making * a write() syscall when we know that the handle is in error mode. */ empty_queue = (stream->write_queue_size == 0); /* Initialize the req */ uv__req_init(stream->loop, req, UV_WRITE); req->cb = cb; req->handle = stream; req->error = 0; req->send_handle = send_handle; QUEUE_INIT(&req->queue); req->bufs = req->bufsml; if (nbufs > ARRAY_SIZE(req->bufsml)) req->bufs = malloc(nbufs * sizeof(bufs[0])); if (req->bufs == NULL) return -ENOMEM; memcpy(req->bufs, bufs, nbufs * sizeof(bufs[0])); req->nbufs = nbufs; req->write_index = 0; stream->write_queue_size += uv_count_bufs(bufs, nbufs); /* Append the request to write_queue. */ QUEUE_INSERT_TAIL(&stream->write_queue, &req->queue); /* If the queue was empty when this function began, we should attempt to * do the write immediately. Otherwise start the write_watcher and wait * for the fd to become writable. */ if (stream->connect_req) { /* Still connecting, do nothing. */ } else if (empty_queue) { uv__write(stream); } else { /* * blocking streams should never have anything in the queue. * if this assert fires then somehow the blocking stream isn't being * sufficiently flushed in uv__write. */ assert(!(stream->flags & UV_STREAM_BLOCKING)); uv__io_start(stream->loop, &stream->io_watcher, UV__POLLOUT); } return 0; } /* The buffers to be written must remain valid until the callback is called. * This is not required for the uv_buf_t array. */ int uv_write(uv_write_t* req, uv_stream_t* handle, const uv_buf_t bufs[], unsigned int nbufs, uv_write_cb cb) { return uv_write2(req, handle, bufs, nbufs, NULL, cb); } static int uv__read_start_common(uv_stream_t* stream, uv_alloc_cb alloc_cb, uv_read_cb read_cb, uv_read2_cb read2_cb) { assert(stream->type == UV_TCP || stream->type == UV_NAMED_PIPE || stream->type == UV_TTY); if (stream->flags & UV_CLOSING) return -EINVAL; /* The UV_STREAM_READING flag is irrelevant of the state of the tcp - it just * expresses the desired state of the user. */ stream->flags |= UV_STREAM_READING; #if defined(__APPLE__) /* Notify select() thread about state change */ if (stream->select != NULL) uv__stream_osx_interrupt_select(stream); #endif /* defined(__APPLE__) */ /* TODO: try to do the read inline? */ /* TODO: keep track of tcp state. If we've gotten a EOF then we should * not start the IO watcher. */ assert(uv__stream_fd(stream) >= 0); assert(alloc_cb); stream->read_cb = read_cb; stream->read2_cb = read2_cb; stream->alloc_cb = alloc_cb; uv__io_start(stream->loop, &stream->io_watcher, UV__POLLIN); uv__handle_start(stream); return 0; } int uv_read_start(uv_stream_t* stream, uv_alloc_cb alloc_cb, uv_read_cb read_cb) { return uv__read_start_common(stream, alloc_cb, read_cb, NULL); } int uv_read2_start(uv_stream_t* stream, uv_alloc_cb alloc_cb, uv_read2_cb read_cb) { return uv__read_start_common(stream, alloc_cb, NULL, read_cb); } int uv_read_stop(uv_stream_t* stream) { /* Sanity check. We're going to stop the handle unless it's primed for * writing but that means there should be some kind of write action in * progress. */ assert(!uv__io_active(&stream->io_watcher, UV__POLLOUT) || !QUEUE_EMPTY(&stream->write_completed_queue) || !QUEUE_EMPTY(&stream->write_queue) || stream->shutdown_req != NULL || stream->connect_req != NULL); stream->flags &= ~UV_STREAM_READING; uv__io_stop(stream->loop, &stream->io_watcher, UV__POLLIN); if (!uv__io_active(&stream->io_watcher, UV__POLLOUT)) uv__handle_stop(stream); #if defined(__APPLE__) /* Notify select() thread about state change */ if (stream->select != NULL) uv__stream_osx_interrupt_select(stream); #endif /* defined(__APPLE__) */ stream->read_cb = NULL; stream->read2_cb = NULL; stream->alloc_cb = NULL; return 0; } int uv_is_readable(const uv_stream_t* stream) { return !!(stream->flags & UV_STREAM_READABLE); } int uv_is_writable(const uv_stream_t* stream) { return !!(stream->flags & UV_STREAM_WRITABLE); } #if defined(__APPLE__) int uv___stream_fd(uv_stream_t* handle) { uv__stream_select_t* s; assert(handle->type == UV_TCP || handle->type == UV_TTY || handle->type == UV_NAMED_PIPE); s = handle->select; if (s != NULL) return s->fd; return handle->io_watcher.fd; } #endif /* defined(__APPLE__) */ void uv__stream_close(uv_stream_t* handle) { #if defined(__APPLE__) /* Terminate select loop first */ if (handle->select != NULL) { uv__stream_select_t* s; s = handle->select; uv_sem_post(&s->close_sem); uv_sem_post(&s->async_sem); uv__stream_osx_interrupt_select(handle); uv_thread_join(&s->thread); uv_sem_destroy(&s->close_sem); uv_sem_destroy(&s->async_sem); uv__close(s->fake_fd); uv__close(s->int_fd); uv_close((uv_handle_t*) &s->async, uv__stream_osx_cb_close); handle->select = NULL; } #endif /* defined(__APPLE__) */ uv__io_close(handle->loop, &handle->io_watcher); uv_read_stop(handle); uv__handle_stop(handle); if (handle->io_watcher.fd != -1) { /* Don't close stdio file descriptors. Nothing good comes from it. */ if (handle->io_watcher.fd > STDERR_FILENO) uv__close(handle->io_watcher.fd); handle->io_watcher.fd = -1; } if (handle->accepted_fd != -1) { uv__close(handle->accepted_fd); handle->accepted_fd = -1; } assert(!uv__io_active(&handle->io_watcher, UV__POLLIN | UV__POLLOUT)); } int uv_stream_set_blocking(uv_stream_t* handle, int blocking) { assert(0 && "implement me"); abort(); return 0; }