1 /* 2 * QEMU System Emulator 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #include "qemu/osdep.h" 25 #include "chardev/char-io.h" 26 27 typedef struct IOWatchPoll { 28 GSource parent; 29 30 QIOChannel *ioc; 31 GSource *src; 32 33 IOCanReadHandler *fd_can_read; 34 GSourceFunc fd_read; 35 void *opaque; 36 } IOWatchPoll; 37 38 static IOWatchPoll *io_watch_poll_from_source(GSource *source) 39 { 40 return container_of(source, IOWatchPoll, parent); 41 } 42 43 static gboolean io_watch_poll_prepare(GSource *source, 44 gint *timeout) 45 { 46 IOWatchPoll *iwp = io_watch_poll_from_source(source); 47 bool now_active = iwp->fd_can_read(iwp->opaque) > 0; 48 bool was_active = iwp->src != NULL; 49 if (was_active == now_active) { 50 return FALSE; 51 } 52 53 if (now_active) { 54 iwp->src = qio_channel_create_watch( 55 iwp->ioc, G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL); 56 g_source_set_callback(iwp->src, iwp->fd_read, iwp->opaque, NULL); 57 g_source_add_child_source(source, iwp->src); 58 g_source_unref(iwp->src); 59 } else { 60 g_source_remove_child_source(source, iwp->src); 61 iwp->src = NULL; 62 } 63 return FALSE; 64 } 65 66 static gboolean io_watch_poll_dispatch(GSource *source, GSourceFunc callback, 67 gpointer user_data) 68 { 69 return G_SOURCE_CONTINUE; 70 } 71 72 static GSourceFuncs io_watch_poll_funcs = { 73 .prepare = io_watch_poll_prepare, 74 .dispatch = io_watch_poll_dispatch, 75 }; 76 77 GSource *io_add_watch_poll(Chardev *chr, 78 QIOChannel *ioc, 79 IOCanReadHandler *fd_can_read, 80 QIOChannelFunc fd_read, 81 gpointer user_data, 82 GMainContext *context) 83 { 84 IOWatchPoll *iwp; 85 char *name; 86 87 iwp = (IOWatchPoll *) g_source_new(&io_watch_poll_funcs, 88 sizeof(IOWatchPoll)); 89 iwp->fd_can_read = fd_can_read; 90 iwp->opaque = user_data; 91 iwp->ioc = ioc; 92 iwp->fd_read = (GSourceFunc) fd_read; 93 iwp->src = NULL; 94 95 name = g_strdup_printf("chardev-iowatch-%s", chr->label); 96 g_source_set_name((GSource *)iwp, name); 97 g_free(name); 98 99 g_source_attach(&iwp->parent, context); 100 g_source_unref(&iwp->parent); 101 return (GSource *)iwp; 102 } 103 104 void remove_fd_in_watch(Chardev *chr) 105 { 106 if (chr->gsource) { 107 g_source_destroy(chr->gsource); 108 chr->gsource = NULL; 109 } 110 } 111 112 int io_channel_send_full(QIOChannel *ioc, 113 const void *buf, size_t len, 114 int *fds, size_t nfds) 115 { 116 size_t offset = 0; 117 118 while (offset < len) { 119 ssize_t ret = 0; 120 struct iovec iov = { .iov_base = (char *)buf + offset, 121 .iov_len = len - offset }; 122 123 ret = qio_channel_writev_full( 124 ioc, &iov, 1, 125 fds, nfds, 0, NULL); 126 if (ret == QIO_CHANNEL_ERR_BLOCK) { 127 if (offset) { 128 return offset; 129 } 130 131 errno = EAGAIN; 132 return -1; 133 } else if (ret < 0) { 134 errno = EINVAL; 135 return -1; 136 } 137 138 offset += ret; 139 } 140 141 return offset; 142 } 143 144 int io_channel_send(QIOChannel *ioc, const void *buf, size_t len) 145 { 146 return io_channel_send_full(ioc, buf, len, NULL, 0); 147 } 148