summaryrefslogtreecommitdiff
path: root/iohandler.c
diff options
context:
space:
mode:
Diffstat (limited to 'iohandler.c')
-rw-r--r--iohandler.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/iohandler.c b/iohandler.c
new file mode 100644
index 0000000000..2e30fe3bcb
--- /dev/null
+++ b/iohandler.c
@@ -0,0 +1,129 @@
+/*
+ * QEMU System Emulator - managing I/O handler
+ *
+ * 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 "config-host.h"
+#include "qemu-common.h"
+#include "qemu-char.h"
+#include "qemu-queue.h"
+
+typedef struct IOHandlerRecord {
+ int fd;
+ IOCanReadHandler *fd_read_poll;
+ IOHandler *fd_read;
+ IOHandler *fd_write;
+ int deleted;
+ void *opaque;
+ QLIST_ENTRY(IOHandlerRecord) next;
+} IOHandlerRecord;
+
+static QLIST_HEAD(, IOHandlerRecord) io_handlers =
+ QLIST_HEAD_INITIALIZER(io_handlers);
+
+
+/* XXX: fd_read_poll should be suppressed, but an API change is
+ necessary in the character devices to suppress fd_can_read(). */
+int qemu_set_fd_handler2(int fd,
+ IOCanReadHandler *fd_read_poll,
+ IOHandler *fd_read,
+ IOHandler *fd_write,
+ void *opaque)
+{
+ IOHandlerRecord *ioh;
+
+ if (!fd_read && !fd_write) {
+ QLIST_FOREACH(ioh, &io_handlers, next) {
+ if (ioh->fd == fd) {
+ ioh->deleted = 1;
+ break;
+ }
+ }
+ } else {
+ QLIST_FOREACH(ioh, &io_handlers, next) {
+ if (ioh->fd == fd)
+ goto found;
+ }
+ ioh = qemu_mallocz(sizeof(IOHandlerRecord));
+ QLIST_INSERT_HEAD(&io_handlers, ioh, next);
+ found:
+ ioh->fd = fd;
+ ioh->fd_read_poll = fd_read_poll;
+ ioh->fd_read = fd_read;
+ ioh->fd_write = fd_write;
+ ioh->opaque = opaque;
+ ioh->deleted = 0;
+ }
+ return 0;
+}
+
+int qemu_set_fd_handler(int fd,
+ IOHandler *fd_read,
+ IOHandler *fd_write,
+ void *opaque)
+{
+ return qemu_set_fd_handler2(fd, NULL, fd_read, fd_write, opaque);
+}
+
+void qemu_iohandler_fill(int *pnfds, fd_set *readfds, fd_set *writefds, fd_set *xfds)
+{
+ IOHandlerRecord *ioh;
+
+ QLIST_FOREACH(ioh, &io_handlers, next) {
+ if (ioh->deleted)
+ continue;
+ if (ioh->fd_read &&
+ (!ioh->fd_read_poll ||
+ ioh->fd_read_poll(ioh->opaque) != 0)) {
+ FD_SET(ioh->fd, readfds);
+ if (ioh->fd > *pnfds)
+ *pnfds = ioh->fd;
+ }
+ if (ioh->fd_write) {
+ FD_SET(ioh->fd, writefds);
+ if (ioh->fd > *pnfds)
+ *pnfds = ioh->fd;
+ }
+ }
+}
+
+void qemu_iohandler_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds, int ret)
+{
+ if (ret > 0) {
+ IOHandlerRecord *pioh, *ioh;
+
+ QLIST_FOREACH_SAFE(ioh, &io_handlers, next, pioh) {
+ if (!ioh->deleted && ioh->fd_read && FD_ISSET(ioh->fd, readfds)) {
+ ioh->fd_read(ioh->opaque);
+ }
+ if (!ioh->deleted && ioh->fd_write && FD_ISSET(ioh->fd, writefds)) {
+ ioh->fd_write(ioh->opaque);
+ }
+
+ /* Do this last in case read/write handlers marked it for deletion */
+ if (ioh->deleted) {
+ QLIST_REMOVE(ioh, next);
+ qemu_free(ioh);
+ }
+ }
+ }
+}