Add qemu 2.4.0
[kvmfornfv.git] / qemu / iohandler.c
diff --git a/qemu/iohandler.c b/qemu/iohandler.c
new file mode 100644 (file)
index 0000000..826f713
--- /dev/null
@@ -0,0 +1,201 @@
+/*
+ * 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/queue.h"
+#include "block/aio.h"
+#include "qemu/main-loop.h"
+
+#ifndef _WIN32
+#include <sys/wait.h>
+#endif
+
+typedef struct IOHandlerRecord {
+    IOHandler *fd_read;
+    IOHandler *fd_write;
+    void *opaque;
+    QLIST_ENTRY(IOHandlerRecord) next;
+    int fd;
+    int pollfds_idx;
+    bool deleted;
+} IOHandlerRecord;
+
+static QLIST_HEAD(, IOHandlerRecord) io_handlers =
+    QLIST_HEAD_INITIALIZER(io_handlers);
+
+void qemu_set_fd_handler(int fd,
+                         IOHandler *fd_read,
+                         IOHandler *fd_write,
+                         void *opaque)
+{
+    IOHandlerRecord *ioh;
+
+    assert(fd >= 0);
+
+    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 = g_malloc0(sizeof(IOHandlerRecord));
+        QLIST_INSERT_HEAD(&io_handlers, ioh, next);
+    found:
+        ioh->fd = fd;
+        ioh->fd_read = fd_read;
+        ioh->fd_write = fd_write;
+        ioh->opaque = opaque;
+        ioh->pollfds_idx = -1;
+        ioh->deleted = 0;
+        qemu_notify_event();
+    }
+}
+
+void qemu_iohandler_fill(GArray *pollfds)
+{
+    IOHandlerRecord *ioh;
+
+    QLIST_FOREACH(ioh, &io_handlers, next) {
+        int events = 0;
+
+        if (ioh->deleted)
+            continue;
+        if (ioh->fd_read) {
+            events |= G_IO_IN | G_IO_HUP | G_IO_ERR;
+        }
+        if (ioh->fd_write) {
+            events |= G_IO_OUT | G_IO_ERR;
+        }
+        if (events) {
+            GPollFD pfd = {
+                .fd = ioh->fd,
+                .events = events,
+            };
+            ioh->pollfds_idx = pollfds->len;
+            g_array_append_val(pollfds, pfd);
+        } else {
+            ioh->pollfds_idx = -1;
+        }
+    }
+}
+
+void qemu_iohandler_poll(GArray *pollfds, int ret)
+{
+    if (ret > 0) {
+        IOHandlerRecord *pioh, *ioh;
+
+        QLIST_FOREACH_SAFE(ioh, &io_handlers, next, pioh) {
+            int revents = 0;
+
+            if (!ioh->deleted && ioh->pollfds_idx != -1) {
+                GPollFD *pfd = &g_array_index(pollfds, GPollFD,
+                                              ioh->pollfds_idx);
+                revents = pfd->revents;
+            }
+
+            if (!ioh->deleted && ioh->fd_read &&
+                (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR))) {
+                ioh->fd_read(ioh->opaque);
+            }
+            if (!ioh->deleted && ioh->fd_write &&
+                (revents & (G_IO_OUT | G_IO_ERR))) {
+                ioh->fd_write(ioh->opaque);
+            }
+
+            /* Do this last in case read/write handlers marked it for deletion */
+            if (ioh->deleted) {
+                QLIST_REMOVE(ioh, next);
+                g_free(ioh);
+            }
+        }
+    }
+}
+
+/* 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