/* * QEMU I/O channels * * Copyright (c) 2015 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, see <http://www.gnu.org/licenses/>. * */ #include "qemu/osdep.h" #include "io/channel.h" #include "qapi/error.h" #include "qemu/coroutine.h" bool qio_channel_has_feature(QIOChannel *ioc, QIOChannelFeature feature) { return ioc->features & (1 << feature); } ssize_t qio_channel_readv_full(QIOChannel *ioc, const struct iovec *iov, size_t niov, int **fds, size_t *nfds, Error **errp) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); if ((fds || nfds) && !(ioc->features & (1 << QIO_CHANNEL_FEATURE_FD_PASS))) { error_setg_errno(errp, EINVAL, "Channel does not support file descriptor passing"); return -1; } return klass->io_readv(ioc, iov, niov, fds, nfds, errp); } ssize_t qio_channel_writev_full(QIOChannel *ioc, const struct iovec *iov, size_t niov, int *fds, size_t nfds, Error **errp) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); if ((fds || nfds) && !(ioc->features & (1 << QIO_CHANNEL_FEATURE_FD_PASS))) { error_setg_errno(errp, EINVAL, "Channel does not support file descriptor passing"); return -1; } return klass->io_writev(ioc, iov, niov, fds, nfds, errp); } ssize_t qio_channel_readv(QIOChannel *ioc, const struct iovec *iov, size_t niov, Error **errp) { return qio_channel_readv_full(ioc, iov, niov, NULL, NULL, errp); } ssize_t qio_channel_writev(QIOChannel *ioc, const struct iovec *iov, size_t niov, Error **errp) { return qio_channel_writev_full(ioc, iov, niov, NULL, 0, errp); } ssize_t qio_channel_read(QIOChannel *ioc, char *buf, size_t buflen, Error **errp) { struct iovec iov = { .iov_base = buf, .iov_len = buflen }; return qio_channel_readv_full(ioc, &iov, 1, NULL, NULL, errp); } ssize_t qio_channel_write(QIOChannel *ioc, const char *buf, size_t buflen, Error **errp) { struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen }; return qio_channel_writev_full(ioc, &iov, 1, NULL, 0, errp); } int qio_channel_set_blocking(QIOChannel *ioc, bool enabled, Error **errp) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); return klass->io_set_blocking(ioc, enabled, errp); } int qio_channel_close(QIOChannel *ioc, Error **errp) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); return klass->io_close(ioc, errp); } GSource *qio_channel_create_watch(QIOChannel *ioc, GIOCondition condition) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); return klass->io_create_watch(ioc, condition); } guint qio_channel_add_watch(QIOChannel *ioc, GIOCondition condition, QIOChannelFunc func, gpointer user_data, GDestroyNotify notify) { GSource *source; guint id; source = qio_channel_create_watch(ioc, condition); g_source_set_callback(source, (GSourceFunc)func, user_data, notify); id = g_source_attach(source, NULL); g_source_unref(source); return id; } int qio_channel_shutdown(QIOChannel *ioc, QIOChannelShutdown how, Error **errp) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); if (!klass->io_shutdown) { error_setg(errp, "Data path shutdown not supported"); return -1; } return klass->io_shutdown(ioc, how, errp); } void qio_channel_set_delay(QIOChannel *ioc, bool enabled) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); if (klass->io_set_delay) { klass->io_set_delay(ioc, enabled); } } void qio_channel_set_cork(QIOChannel *ioc, bool enabled) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); if (klass->io_set_cork) { klass->io_set_cork(ioc, enabled); } } off_t qio_channel_io_seek(QIOChannel *ioc, off_t offset, int whence, Error **errp) { QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc); if (!klass->io_seek) { error_setg(errp, "Channel does not support random access"); return -1; } return klass->io_seek(ioc, offset, whence, errp); } typedef struct QIOChannelYieldData QIOChannelYieldData; struct QIOChannelYieldData { QIOChannel *ioc; Coroutine *co; }; static gboolean qio_channel_yield_enter(QIOChannel *ioc, GIOCondition condition, gpointer opaque) { QIOChannelYieldData *data = opaque; qemu_coroutine_enter(data->co); return FALSE; } void coroutine_fn qio_channel_yield(QIOChannel *ioc, GIOCondition condition) { QIOChannelYieldData data; assert(qemu_in_coroutine()); data.ioc = ioc; data.co = qemu_coroutine_self(); qio_channel_add_watch(ioc, condition, qio_channel_yield_enter, &data, NULL); qemu_coroutine_yield(); } static gboolean qio_channel_wait_complete(QIOChannel *ioc, GIOCondition condition, gpointer opaque) { GMainLoop *loop = opaque; g_main_loop_quit(loop); return FALSE; } void qio_channel_wait(QIOChannel *ioc, GIOCondition condition) { GMainContext *ctxt = g_main_context_new(); GMainLoop *loop = g_main_loop_new(ctxt, TRUE); GSource *source; source = qio_channel_create_watch(ioc, condition); g_source_set_callback(source, (GSourceFunc)qio_channel_wait_complete, loop, NULL); g_source_attach(source, ctxt); g_main_loop_run(loop); g_source_unref(source); g_main_loop_unref(loop); g_main_context_unref(ctxt); } #ifdef _WIN32 static void qio_channel_finalize(Object *obj) { QIOChannel *ioc = QIO_CHANNEL(obj); if (ioc->event) { CloseHandle(ioc->event); } } #endif static const TypeInfo qio_channel_info = { .parent = TYPE_OBJECT, .name = TYPE_QIO_CHANNEL, .instance_size = sizeof(QIOChannel), #ifdef _WIN32 .instance_finalize = qio_channel_finalize, #endif .abstract = true, .class_size = sizeof(QIOChannelClass), }; static void qio_channel_register_types(void) { type_register_static(&qio_channel_info); } type_init(qio_channel_register_types);