Change assets to use 64-bit API

The asset system and supporting libraries were using off_t instead of
off64_t to access files larger than 2GB (32-bit signed). This change
replaces all off_t with off64_t and lseek64.

There is a new utils/Compat.h added for Mac OS compatibility.

Also fixed some size-related compiler warnings.

Bug: 3205336
Change-Id: I9097b3cb7a602e811fe52f245939d8975da55e9e
diff --git a/include/utils/Compat.h b/include/utils/Compat.h
new file mode 100644
index 0000000..1819266
--- /dev/null
+++ b/include/utils/Compat.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef __LIB_UTILS_COMPAT_H
+#define __LIB_UTILS_COMPAT_H
+
+#include <unistd.h>
+
+/* Compatibility definitions for non-Linux (i.e., BSD-based) hosts. */
+#ifndef HAVE_OFF64_T
+#if _FILE_OFFSET_BITS < 64
+#error "_FILE_OFFSET_BITS < 64; large files are not supported on this platform"
+#endif /* _FILE_OFFSET_BITS < 64 */
+
+typedef off_t off64_t;
+
+static inline off64_t lseek64(int fd, off64_t offset, int whence) {
+    return lseek(fd, offset, whence);
+}
+
+#ifdef HAVE_PREAD
+static inline ssize_t pread64(int fd, void* buf, size_t nbytes, off64_t offset) {
+    return pread(fd, buf, nbytes, offset);
+}
+#endif
+
+#endif /* !HAVE_OFF64_T */
+
+#endif /* __LIB_UTILS_COMPAT_H */