1 files changed, 80 insertions, 0 deletions
diff --git a/src/os_common/os_errno.c b/src/os_common/os_errno.c
new file mode 100644
index 00000000000..a8e56b7f1aa
--- /dev/null
+++ b/src/os_common/os_errno.c
@@ -0,0 +1,80 @@
+/*-
+ * Copyright (c) 2014-2016 MongoDB, Inc.
+ * Copyright (c) 2008-2014 WiredTiger, Inc.
+ *	All rights reserved.
+ *
+ * See the file LICENSE for redistribution information.
+ */
+
+#include "wt_internal.h"
+
+/*
+ * __wt_errno --
+ *	Return errno, or WT_ERROR if errno not set.
+ */
+int
+__wt_errno(void)
+{
+	/*
+	 * Called when we know an error occurred, and we want the system
+	 * error code, but there's some chance it's not set.
+	 */
+	return (errno == 0 ? WT_ERROR : errno);
+}
+
+/*
+ * __wt_strerror --
+ *	WT_SESSION.strerror and wiredtiger_strerror.
+ */
+const char *
+__wt_strerror(WT_SESSION_IMPL *session, int error, char *errbuf, size_t errlen)
+{
+	const char *p;
+
+	/*
+	 * Check for a WiredTiger or POSIX constant string, no buffer needed.
+	 */
+	if ((p = __wt_wiredtiger_error(error)) != NULL)
+		return (p);
+
+	/*
+	 * When called from wiredtiger_strerror, write a passed-in buffer.
+	 * When called from WT_SESSION.strerror, write the session's buffer.
+	 *
+	 * Fallback to a generic message.
+	 */
+	if (session == NULL &&
+	    snprintf(errbuf, errlen, "error return: %d", error) > 0)
+		return (errbuf);
+	if (session != NULL && __wt_buf_fmt(
+	    session, &session->err, "error return: %d", error) == 0)
+		return (session->err.data);
+
+	/* Defeated. */
+	return ("Unable to return error string");
+}
+
+/*
+ * __wt_ext_map_windows_error --
+ *	Extension API call to map a Windows system error to a POSIX/ANSI error.
+ */
+int
+__wt_ext_map_windows_error(
+    WT_EXTENSION_API *wt_api, WT_SESSION *wt_session, uint32_t windows_error)
+{
+	WT_UNUSED(wt_api);
+	WT_UNUSED(wt_session);
+
+	/*
+	 * This extension API only makes sense in Windows builds, but it's hard
+	 * to exclude it otherwise (there's no way to return an error, anyway).
+	 * Call an underlying function on Windows, else panic so callers figure
+	 * out what they're doing wrong.
+	 */
+#ifdef _WIN32
+	return (__wt_map_windows_error(windows_error));
+#else
+	WT_UNUSED(windows_error);
+	return (WT_PANIC);
+#endif
+}