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-rw-r--r--storage/bdb/common/db_byteorder.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/storage/bdb/common/db_byteorder.c b/storage/bdb/common/db_byteorder.c
new file mode 100644
index 00000000000..d42d8e6a958
--- /dev/null
+++ b/storage/bdb/common/db_byteorder.c
@@ -0,0 +1,74 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996-2002
+ * Sleepycat Software. All rights reserved.
+ */
+
+#include "db_config.h"
+
+#ifndef lint
+static const char revid[] = "$Id: db_byteorder.c,v 11.8 2002/02/01 18:15:29 bostic Exp $";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+#endif
+
+#include "db_int.h"
+
+/*
+ * __db_isbigendian --
+ * Return 1 if big-endian (Motorola and Sparc), not little-endian
+ * (Intel and Vax). We do this work at run-time, rather than at
+ * configuration time so cross-compilation and general embedded
+ * system support is simpler.
+ *
+ * PUBLIC: int __db_isbigendian __P((void));
+ */
+int
+__db_isbigendian()
+{
+ union { /* From Harbison & Steele. */
+ long l;
+ char c[sizeof(long)];
+ } u;
+
+ u.l = 1;
+ return (u.c[sizeof(long) - 1] == 1);
+}
+
+/*
+ * __db_byteorder --
+ * Return if we need to do byte swapping, checking for illegal
+ * values.
+ *
+ * PUBLIC: int __db_byteorder __P((DB_ENV *, int));
+ */
+int
+__db_byteorder(dbenv, lorder)
+ DB_ENV *dbenv;
+ int lorder;
+{
+ int is_bigendian;
+
+ is_bigendian = __db_isbigendian();
+
+ switch (lorder) {
+ case 0:
+ break;
+ case 1234:
+ if (is_bigendian)
+ return (DB_SWAPBYTES);
+ break;
+ case 4321:
+ if (!is_bigendian)
+ return (DB_SWAPBYTES);
+ break;
+ default:
+ __db_err(dbenv,
+ "unsupported byte order, only big and little-endian supported");
+ return (EINVAL);
+ }
+ return (0);
+}