1 files changed, 25 insertions, 0 deletions
diff --git a/libc-bottom-half/cloudlibc/src/libc/unistd/lseek.c b/libc-bottom-half/cloudlibc/src/libc/unistd/lseek.c
new file mode 100644
index 0000000..3e0429f
--- /dev/null
+++ b/libc-bottom-half/cloudlibc/src/libc/unistd/lseek.c
@@ -0,0 +1,25 @@
+// Copyright (c) 2015-2016 Nuxi, https://nuxi.nl/
+//
+// SPDX-License-Identifier: BSD-2-Clause
+
+#include <assert.h>
+#include <wasi/api.h>
+#include <errno.h>
+#include <unistd.h>
+
+static_assert(SEEK_CUR == __WASI_WHENCE_CUR, "Value mismatch");
+static_assert(SEEK_END == __WASI_WHENCE_END, "Value mismatch");
+static_assert(SEEK_SET == __WASI_WHENCE_SET, "Value mismatch");
+
+off_t __lseek(int fildes, off_t offset, int whence) {
+  __wasi_filesize_t new_offset;
+  __wasi_errno_t error =
+      __wasi_fd_seek(fildes, offset, whence, &new_offset);
+  if (error != 0) {
+    errno = error == ENOTCAPABLE ? ESPIPE : error;
+    return -1;
+  }
+  return new_offset;
+}
+
+weak_alias(__lseek, lseek);