| /* |
| * Coroutine-aware I/O functions |
| * |
| * Copyright (C) 2009-2010 Nippon Telegraph and Telephone Corporation. |
| * Copyright (c) 2011, Red Hat, Inc. |
| * |
| * 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 "qemu/osdep.h" |
| #include "qemu-common.h" |
| #include "qemu/sockets.h" |
| #include "qemu/coroutine.h" |
| #include "qemu/iov.h" |
| #include "qemu/main-loop.h" |
| |
| ssize_t coroutine_fn |
| qemu_co_sendv_recvv(int sockfd, struct iovec *iov, unsigned iov_cnt, |
| size_t offset, size_t bytes, bool do_send) |
| { |
| size_t done = 0; |
| ssize_t ret; |
| while (done < bytes) { |
| ret = iov_send_recv(sockfd, iov, iov_cnt, |
| offset + done, bytes - done, do_send); |
| if (ret > 0) { |
| done += ret; |
| } else if (ret < 0) { |
| if (errno == EAGAIN || errno == EWOULDBLOCK) { |
| qemu_coroutine_yield(); |
| } else if (done == 0) { |
| return -errno; |
| } else { |
| break; |
| } |
| } else if (ret == 0 && !do_send) { |
| /* write (send) should never return 0. |
| * read (recv) returns 0 for end-of-file (-data). |
| * In both cases there's little point retrying, |
| * but we do for write anyway, just in case */ |
| break; |
| } |
| } |
| return done; |
| } |
| |
| ssize_t coroutine_fn |
| qemu_co_send_recv(int sockfd, void *buf, size_t bytes, bool do_send) |
| { |
| struct iovec iov = { .iov_base = buf, .iov_len = bytes }; |
| return qemu_co_sendv_recvv(sockfd, &iov, 1, 0, bytes, do_send); |
| } |
| |
| typedef struct { |
| Coroutine *co; |
| int fd; |
| } FDYieldUntilData; |
| |
| static void fd_coroutine_enter(void *opaque) |
| { |
| FDYieldUntilData *data = opaque; |
| qemu_set_fd_handler(data->fd, NULL, NULL, NULL); |
| qemu_coroutine_enter(data->co); |
| } |
| |
| void coroutine_fn yield_until_fd_readable(int fd) |
| { |
| FDYieldUntilData data; |
| |
| assert(qemu_in_coroutine()); |
| data.co = qemu_coroutine_self(); |
| data.fd = fd; |
| qemu_set_fd_handler(fd, fd_coroutine_enter, NULL, &data); |
| qemu_coroutine_yield(); |
| } |