qemu-coroutine-io.c

   1 /*
   2  * Coroutine-aware I/O functions
   3  *
   4  * Copyright (C) 2009-2010 Nippon Telegraph and Telephone Corporation.
   5  * Copyright (c) 2011, Red Hat, Inc.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25 #include "qemu-common.h"
  26 #include "qemu_socket.h"
  27 #include "qemu-coroutine.h"
  28
  29 int coroutine_fn qemu_co_recvv(int sockfd, struct iovec *iov,
  30                                int len, int iov_offset)
  31 {
  32     int total = 0;
  33     int ret;
  34     while (len) {
  35         ret = qemu_recvv(sockfd, iov, len, iov_offset + total);
  36         if (ret < 0) {
  37             if (errno == EAGAIN) {
  38                 qemu_coroutine_yield();
  39                 continue;
  40             }
  41             if (total == 0) {
  42                 total = -1;
  43             }
  44             break;
  45         }
  46         if (ret == 0) {
  47             break;
  48         }
  49         total += ret, len -= ret;
  50     }
  51
  52     return total;
  53 }
  54
  55 int coroutine_fn qemu_co_sendv(int sockfd, struct iovec *iov,
  56                                int len, int iov_offset)
  57 {
  58     int total = 0;
  59     int ret;
  60     while (len) {
  61         ret = qemu_sendv(sockfd, iov, len, iov_offset + total);
  62         if (ret < 0) {
  63             if (errno == EAGAIN) {
  64                 qemu_coroutine_yield();
  65                 continue;
  66             }
  67             if (total == 0) {
  68                 total = -1;
  69             }
  70             break;
  71         }
  72         total += ret, len -= ret;
  73     }
  74
  75     return total;
  76 }
  77
  78 int coroutine_fn qemu_co_recv(int sockfd, void *buf, int len)
  79 {
  80     struct iovec iov;
  81
  82     iov.iov_base = buf;
  83     iov.iov_len = len;
  84
  85     return qemu_co_recvv(sockfd, &iov, len, 0);
  86 }
  87
  88 int coroutine_fn qemu_co_send(int sockfd, void *buf, int len)
  89 {
  90     struct iovec iov;
  91
  92     iov.iov_base = buf;
  93     iov.iov_len = len;
  94
  95     return qemu_co_sendv(sockfd, &iov, len, 0);
  96 }