sync: Add lib sync helper library
Used to talk to kernel synchronization framework
Change-Id: I66e1f4a90f5d58d384bf1cec09db52101f182c5e
Signed-off-by: Erik Gilling <konkers@android.com>
diff --git a/libsync/sync.c b/libsync/sync.c
new file mode 100644
index 0000000..311da14
--- /dev/null
+++ b/libsync/sync.c
@@ -0,0 +1,115 @@
+/*
+ * sync.c
+ *
+ * Copyright 2012 Google, Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <fcntl.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <sync/sync.h>
+
+int sync_wait(int fd, unsigned int timeout)
+{
+ __u32 to = timeout;
+
+ return ioctl(fd, SYNC_IOC_WAIT, &to);
+}
+
+int sync_merge(const char *name, int fd1, int fd2)
+{
+ struct sync_merge_data data;
+ int err;
+
+ data.fd2 = fd2;
+ strlcpy(data.name, name, sizeof(data.name));
+
+ err = ioctl(fd1, SYNC_IOC_MERGE, &data);
+ if (err < 0)
+ return err;
+
+ return data.fence;
+}
+
+struct sync_fence_info_data *sync_fence_info(int fd)
+{
+ struct sync_fence_info_data *info;
+ int err;
+
+ info = malloc(4096);
+ if (info == NULL)
+ return NULL;
+
+ info->len = 4096;
+ err = ioctl(fd, SYNC_IOC_FENCE_INFO, info);
+ if (err < 0) {
+ free(info);
+ return NULL;
+ }
+
+ return info;
+}
+
+struct sync_pt_info *sync_pt_info(struct sync_fence_info_data *info,
+ struct sync_pt_info *itr)
+{
+ if (itr == NULL)
+ itr = (struct sync_pt_info *) info->pt_info;
+ else
+ itr = (struct sync_pt_info *) ((__u8 *)itr + itr->len);
+
+ if ((__u8 *)itr - (__u8 *)info >= (int)info->len)
+ return NULL;
+
+ return itr;
+}
+
+void sync_fence_info_free(struct sync_fence_info_data *info)
+{
+ free(info);
+}
+
+
+int sw_sync_timeline_create(void)
+{
+ return open("/dev/sw_sync", O_RDWR);
+}
+
+int sw_sync_timeline_inc(int fd, unsigned count)
+{
+ __u32 arg = count;
+
+ return ioctl(fd, SW_SYNC_IOC_INC, &arg);
+}
+
+int sw_sync_fence_create(int fd, const char *name, unsigned value)
+{
+ struct sw_sync_create_fence_data data;
+ int err;
+
+ data.value = value;
+ strlcpy(data.name, name, sizeof(data.name));
+
+ err = ioctl(fd, SW_SYNC_IOC_CREATE_FENCE, &data);
+ if (err < 0)
+ return err;
+
+ return data.fence;
+}