1 files changed, 49 insertions, 0 deletions
diff --git a/libc/src/stdio/baremetal/vprintf.cpp b/libc/src/stdio/baremetal/vprintf.cpp
new file mode 100644
index 000000000000..cd1541297f3b
--- /dev/null
+++ b/libc/src/stdio/baremetal/vprintf.cpp
@@ -0,0 +1,49 @@
+//===-- Implementation of vprintf -------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/stdio/vprintf.h"
+#include "src/__support/OSUtil/io.h"
+#include "src/__support/arg_list.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/printf_main.h"
+#include "src/stdio/printf_core/writer.h"
+
+#include <stdarg.h>
+
+namespace LIBC_NAMESPACE {
+
+namespace {
+
+LIBC_INLINE int raw_write_hook(cpp::string_view new_str, void *) {
+  write_to_stderr(new_str);
+  return printf_core::WRITE_OK;
+}
+
+} // namespace
+
+LLVM_LIBC_FUNCTION(int, vprintf,
+                   (const char *__restrict format, va_list vlist)) {
+  internal::ArgList args(vlist); // This holder class allows for easier copying
+                                 // and pointer semantics, as well as handling
+                                 // destruction automatically.
+  constexpr size_t BUFF_SIZE = 1024;
+  char buffer[BUFF_SIZE];
+
+  printf_core::WriteBuffer wb(buffer, BUFF_SIZE, &raw_write_hook, nullptr);
+  printf_core::Writer writer(&wb);
+
+  int retval = printf_core::printf_main(&writer, format, args);
+
+  int flushval = wb.overflow_write("");
+  if (flushval != printf_core::WRITE_OK)
+    retval = flushval;
+
+  return retval;
+}
+
+} // namespace LIBC_NAMESPACE