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author | Marc-André Lureau <marcandre.lureau@redhat.com> | 2016-12-12 17:07:52 +0300 |
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committer | Marc-André Lureau <marcandre.lureau@redhat.com> | 2017-01-31 23:31:20 +0400 |
commit | a6da7ffa38f7715f863b4e926dd2cce6b5ce4acd (patch) | |
tree | 1cefbf49dcae0cd9359287042f329701285531e0 /chardev/char-io.c | |
parent | 09fbe4e3e1e8a0742d46327440835e1c1b57d030 (diff) | |
download | qemu-a6da7ffa38f7715f863b4e926dd2cce6b5ce4acd.zip qemu-a6da7ffa38f7715f863b4e926dd2cce6b5ce4acd.tar.gz qemu-a6da7ffa38f7715f863b4e926dd2cce6b5ce4acd.tar.bz2 |
char: move QIOChannel-related stuff to char-io.h
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Diffstat (limited to 'chardev/char-io.c')
-rw-r--r-- | chardev/char-io.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/chardev/char-io.c b/chardev/char-io.c new file mode 100644 index 0000000..7dfc3f2 --- /dev/null +++ b/chardev/char-io.c @@ -0,0 +1,192 @@ +/* + * QEMU System Emulator + * + * Copyright (c) 2003-2008 Fabrice Bellard + * + * 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 "char-io.h" + +typedef struct IOWatchPoll { + GSource parent; + + QIOChannel *ioc; + GSource *src; + + IOCanReadHandler *fd_can_read; + GSourceFunc fd_read; + void *opaque; + GMainContext *context; +} IOWatchPoll; + +static IOWatchPoll *io_watch_poll_from_source(GSource *source) +{ + return container_of(source, IOWatchPoll, parent); +} + +static gboolean io_watch_poll_prepare(GSource *source, + gint *timeout) +{ + IOWatchPoll *iwp = io_watch_poll_from_source(source); + bool now_active = iwp->fd_can_read(iwp->opaque) > 0; + bool was_active = iwp->src != NULL; + if (was_active == now_active) { + return FALSE; + } + + if (now_active) { + iwp->src = qio_channel_create_watch( + iwp->ioc, G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL); + g_source_set_callback(iwp->src, iwp->fd_read, iwp->opaque, NULL); + g_source_attach(iwp->src, iwp->context); + } else { + g_source_destroy(iwp->src); + g_source_unref(iwp->src); + iwp->src = NULL; + } + return FALSE; +} + +static gboolean io_watch_poll_check(GSource *source) +{ + return FALSE; +} + +static gboolean io_watch_poll_dispatch(GSource *source, GSourceFunc callback, + gpointer user_data) +{ + abort(); +} + +static void io_watch_poll_finalize(GSource *source) +{ + /* Due to a glib bug, removing the last reference to a source + * inside a finalize callback causes recursive locking (and a + * deadlock). This is not a problem inside other callbacks, + * including dispatch callbacks, so we call io_remove_watch_poll + * to remove this source. At this point, iwp->src must + * be NULL, or we would leak it. + * + * This would be solved much more elegantly by child sources, + * but we support older glib versions that do not have them. + */ + IOWatchPoll *iwp = io_watch_poll_from_source(source); + assert(iwp->src == NULL); +} + +static GSourceFuncs io_watch_poll_funcs = { + .prepare = io_watch_poll_prepare, + .check = io_watch_poll_check, + .dispatch = io_watch_poll_dispatch, + .finalize = io_watch_poll_finalize, +}; + +guint io_add_watch_poll(Chardev *chr, + QIOChannel *ioc, + IOCanReadHandler *fd_can_read, + QIOChannelFunc fd_read, + gpointer user_data, + GMainContext *context) +{ + IOWatchPoll *iwp; + int tag; + char *name; + + iwp = (IOWatchPoll *) g_source_new(&io_watch_poll_funcs, + sizeof(IOWatchPoll)); + iwp->fd_can_read = fd_can_read; + iwp->opaque = user_data; + iwp->ioc = ioc; + iwp->fd_read = (GSourceFunc) fd_read; + iwp->src = NULL; + iwp->context = context; + + name = g_strdup_printf("chardev-iowatch-%s", chr->label); + g_source_set_name((GSource *)iwp, name); + g_free(name); + + tag = g_source_attach(&iwp->parent, context); + g_source_unref(&iwp->parent); + return tag; +} + +static void io_remove_watch_poll(guint tag) +{ + GSource *source; + IOWatchPoll *iwp; + + g_return_if_fail(tag > 0); + + source = g_main_context_find_source_by_id(NULL, tag); + g_return_if_fail(source != NULL); + + iwp = io_watch_poll_from_source(source); + if (iwp->src) { + g_source_destroy(iwp->src); + g_source_unref(iwp->src); + iwp->src = NULL; + } + g_source_destroy(&iwp->parent); +} + +void remove_fd_in_watch(Chardev *chr) +{ + if (chr->fd_in_tag) { + io_remove_watch_poll(chr->fd_in_tag); + chr->fd_in_tag = 0; + } +} + +int io_channel_send_full(QIOChannel *ioc, + const void *buf, size_t len, + int *fds, size_t nfds) +{ + size_t offset = 0; + + while (offset < len) { + ssize_t ret = 0; + struct iovec iov = { .iov_base = (char *)buf + offset, + .iov_len = len - offset }; + + ret = qio_channel_writev_full( + ioc, &iov, 1, + fds, nfds, NULL); + if (ret == QIO_CHANNEL_ERR_BLOCK) { + if (offset) { + return offset; + } + + errno = EAGAIN; + return -1; + } else if (ret < 0) { + errno = EINVAL; + return -1; + } + + offset += ret; + } + + return offset; +} + +int io_channel_send(QIOChannel *ioc, const void *buf, size_t len) +{ + return io_channel_send_full(ioc, buf, len, NULL, 0); +} |