/* * 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); } } 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