Merge "Add native_handle_init"
diff --git a/include/cutils/native_handle.h b/include/cutils/native_handle.h
index 813dadc..7d6a988 100644
--- a/include/cutils/native_handle.h
+++ b/include/cutils/native_handle.h
@@ -17,10 +17,17 @@
#ifndef NATIVE_HANDLE_H_
#define NATIVE_HANDLE_H_
+#include <stdalign.h>
+
#ifdef __cplusplus
extern "C" {
#endif
+/* Declare a char array for use with native_handle_init */
+#define NATIVE_HANDLE_DECLARE_STORAGE(name, maxFds, maxInts) \
+ alignas(native_handle_t) char name[ \
+ sizeof(native_handle_t) + sizeof(int) * (maxFds + maxInts)]
+
typedef struct native_handle
{
int version; /* sizeof(native_handle_t) */
@@ -46,6 +53,14 @@
*/
int native_handle_close(const native_handle_t* h);
+/*
+ * native_handle_init
+ *
+ * Initializes a native_handle_t from storage. storage must be declared with
+ * NATIVE_HANDLE_DECLARE_STORAGE. numFds and numInts must not respectively
+ * exceed maxFds and maxInts used to declare the storage.
+ */
+native_handle_t* native_handle_init(char* storage, int numFds, int numInts);
/*
* native_handle_create
diff --git a/libcutils/native_handle.c b/libcutils/native_handle.c
index cae146d..9f4840a 100644
--- a/libcutils/native_handle.c
+++ b/libcutils/native_handle.c
@@ -28,6 +28,20 @@
static const int kMaxNativeFds = 1024;
static const int kMaxNativeInts = 1024;
+native_handle_t* native_handle_init(char* storage, int numFds, int numInts)
+{
+ if ((uintptr_t) storage % alignof(native_handle_t)) {
+ return NULL;
+ }
+
+ native_handle_t* handle = (native_handle_t*) storage;
+ handle->version = sizeof(native_handle_t);
+ handle->numFds = numFds;
+ handle->numInts = numInts;
+
+ return handle;
+}
+
native_handle_t* native_handle_create(int numFds, int numInts)
{
if (numFds < 0 || numInts < 0 || numFds > kMaxNativeFds || numInts > kMaxNativeInts) {