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/*
* 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 "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/queue.h"
#include "block/aio.h"
#include "qemu/main-loop.h"
#ifndef _WIN32
#include <sys/wait.h>
#endif
/* This context runs on top of main loop. We can't reuse qemu_aio_context
* because iohandlers mustn't be polled by aio_poll(qemu_aio_context). */
static AioContext *iohandler_ctx;
static void iohandler_init(void)
{
if (!iohandler_ctx) {
iohandler_ctx = aio_context_new(&error_abort);
}
}
AioContext *iohandler_get_aio_context(void)
{
iohandler_init();
return iohandler_ctx;
}
GSource *iohandler_get_g_source(void)
{
iohandler_init();
return aio_get_g_source(iohandler_ctx);
}
void qemu_set_fd_handler(int fd,
IOHandler *fd_read,
IOHandler *fd_write,
void *opaque)
{
iohandler_init();
aio_set_fd_handler(iohandler_ctx, fd, false,
fd_read, fd_write, opaque);
}
/* reaping of zombies. right now we're not passing the status to
anyone, but it would be possible to add a callback. */
#ifndef _WIN32
typedef struct ChildProcessRecord {
int pid;
QLIST_ENTRY(ChildProcessRecord) next;
} ChildProcessRecord;
static QLIST_HEAD(, ChildProcessRecord) child_watches =
QLIST_HEAD_INITIALIZER(child_watches);
static QEMUBH *sigchld_bh;
static void sigchld_handler(int signal)
{
qemu_bh_schedule(sigchld_bh);
}
static void sigchld_bh_handler(void *opaque)
{
ChildProcessRecord *rec, *next;
QLIST_FOREACH_SAFE(rec, &child_watches, next, next) {
if (waitpid(rec->pid, NULL, WNOHANG) == rec->pid) {
QLIST_REMOVE(rec, next);
g_free(rec);
}
}
}
static void qemu_init_child_watch(void)
{
struct sigaction act;
sigchld_bh = qemu_bh_new(sigchld_bh_handler, NULL);
memset(&act, 0, sizeof(act));
act.sa_handler = sigchld_handler;
act.sa_flags = SA_NOCLDSTOP;
sigaction(SIGCHLD, &act, NULL);
}
int qemu_add_child_watch(pid_t pid)
{
ChildProcessRecord *rec;
if (!sigchld_bh) {
qemu_init_child_watch();
}
QLIST_FOREACH(rec, &child_watches, next) {
if (rec->pid == pid) {
return 1;
}
}
rec = g_malloc0(sizeof(ChildProcessRecord));
rec->pid = pid;
QLIST_INSERT_HEAD(&child_watches, rec, next);
return 0;
}
#endif