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 #include "iov.h"
  29
  30 int coroutine_fn qemu_co_recvv(int sockfd, struct iovec *iov,
  31                                int len, int iov_offset)
  32 {
  33     int total = 0;
  34     int ret;
  35     while (len) {
  36         ret = iov_recv(sockfd, iov, iov_offset + total, len);
  37         if (ret < 0) {
  38             if (errno == EAGAIN) {
  39                 qemu_coroutine_yield();
  40                 continue;
  41             }
  42             if (total == 0) {
  43                 total = -1;
  44             }
  45             break;
  46         }
  47         if (ret == 0) {
  48             break;
  49         }
  50         total += ret, len -= ret;
  51     }
  52
  53     return total;
  54 }
  55
  56 int coroutine_fn qemu_co_sendv(int sockfd, struct iovec *iov,
  57                                int len, int iov_offset)
  58 {
  59     int total = 0;
  60     int ret;
  61     while (len) {
  62         ret = iov_send(sockfd, iov, iov_offset + total, len);
  63         if (ret < 0) {
  64             if (errno == EAGAIN) {
  65                 qemu_coroutine_yield();
  66                 continue;
  67             }
  68             if (total == 0) {
  69                 total = -1;
  70             }
  71             break;
  72         }
  73         total += ret, len -= ret;
  74     }
  75
  76     return total;
  77 }
  78
  79 int coroutine_fn qemu_co_recv(int sockfd, void *buf, int len)
  80 {
  81     struct iovec iov;
  82
  83     iov.iov_base = buf;
  84     iov.iov_len = len;
  85
  86     return qemu_co_recvv(sockfd, &iov, len, 0);
  87 }
  88
  89 int coroutine_fn qemu_co_send(int sockfd, void *buf, int len)
  90 {
  91     struct iovec iov;
  92
  93     iov.iov_base = buf;
  94     iov.iov_len = len;
  95
  96     return qemu_co_sendv(sockfd, &iov, len, 0);
  97 }