core: ask RealtimeKit for RT scheduling

src/pulsecore/rtkit.c

@@ -0,0 +1,189 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+  Copyright 2009 Lennart Poettering
+
+  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 <errno.h>
+
+#include "rtkit.h"
+
+#ifdef __linux__
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/syscall.h>
+
+static pid_t _gettid(void) {
+        return (pid_t) syscall(SYS_gettid);
+}
+
+static int translate_error(const char *name) {
+        if (strcmp(name, DBUS_ERROR_NO_MEMORY) == 0)
+                return -ENOMEM;
+        if (strcmp(name, DBUS_ERROR_SERVICE_UNKNOWN) == 0 ||
+            strcmp(name, DBUS_ERROR_NAME_HAS_NO_OWNER) == 0)
+                return -ENOENT;
+        if (strcmp(name, DBUS_ERROR_ACCESS_DENIED) == 0 ||
+            strcmp(name, DBUS_ERROR_AUTH_FAILED) == 0)
+                return -EACCES;
+
+        return -EIO;
+}
+
+int rtkit_make_realtime(DBusConnection *connection, pid_t thread, int priority) {
+        DBusMessage *m = NULL, *r = NULL;
+        dbus_uint64_t u64;
+        dbus_uint32_t u32;
+        DBusError error;
+        int ret;
+
+        dbus_error_init(&error);
+
+        if (thread == 0)
+                thread = _gettid();
+
+        if (!(m = dbus_message_new_method_call(
+                              RTKIT_SERVICE_NAME,
+                              RTKIT_OBJECT_PATH,
+                              "org.freedesktop.RealtimeKit1",
+                              "MakeThreadRealtime"))) {
+                ret = -ENOMEM;
+                goto finish;
+        }
+
+        u64 = (dbus_uint64_t) thread;
+        u32 = (dbus_uint32_t) priority;
+
+        if (!dbus_message_append_args(
+                            m,
+                            DBUS_TYPE_UINT64, &u64,
+                            DBUS_TYPE_UINT32, &u32,
+                            DBUS_TYPE_INVALID)) {
+                ret = -ENOMEM;
+                goto finish;
+        }
+
+        if (!(r = dbus_connection_send_with_reply_and_block(connection, m, -1, &error))) {
+                ret = translate_error(error.name);
+                goto finish;
+        }
+
+
+        if (dbus_set_error_from_message(&error, r)) {
+                ret = translate_error(error.name);
+                goto finish;
+        }
+
+        ret = 0;
+
+finish:
+
+        if (m)
+                dbus_message_unref(m);
+
+        if (r)
+                dbus_message_unref(r);
+
+        dbus_error_free(&error);
+
+        return ret;
+}
+
+int rtkit_make_high_priority(DBusConnection *connection, pid_t thread, int nice_level) {
+        DBusMessage *m = NULL, *r = NULL;
+        dbus_uint64_t u64;
+        dbus_int32_t s32;
+        DBusError error;
+        int ret;
+
+        dbus_error_init(&error);
+
+        if (thread == 0)
+                thread = _gettid();
+
+        if (!(m = dbus_message_new_method_call(
+                              RTKIT_SERVICE_NAME,
+                              RTKIT_OBJECT_PATH,
+                              "org.freedesktop.RealtimeKit1",
+                              "MakeThreadHighPriority"))) {
+                ret = -ENOMEM;
+                goto finish;
+        }
+
+        u64 = (dbus_uint64_t) thread;
+        s32 = (dbus_int32_t) nice_level;
+
+        if (!dbus_message_append_args(
+                            m,
+                            DBUS_TYPE_UINT64, &u64,
+                            DBUS_TYPE_INT32, &s32,
+                            DBUS_TYPE_INVALID)) {
+                ret = -ENOMEM;
+                goto finish;
+        }
+
+
+
+        if (!(r = dbus_connection_send_with_reply_and_block(connection, m, -1, &error))) {
+                ret = translate_error(error.name);
+                goto finish;
+        }
+
+
+        if (dbus_set_error_from_message(&error, r)) {
+                ret = translate_error(error.name);
+                goto finish;
+        }
+
+        ret = 0;
+
+finish:
+
+        if (m)
+                dbus_message_unref(m);
+
+        if (r)
+                dbus_message_unref(r);
+
+        dbus_error_free(&error);
+
+        return ret;
+}
+
+#else
+
+int rtkit_make_realtime(DBusConnection *connection, pid_t thread, int priority) {
+        return -ENOTSUP;
+}
+
+int rtkit_make_high_priority(DBusConnection *connection, pid_t thread, int nice_level) {
+        return -ENOTSUP;
+}
+
+#endif