libc/src/stdio/generic/fscanf.cpp

//===-- Implementation of fscanf --------------------------------*- 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/fscanf.h"

#include "src/__support/File/file.h"
#include "src/__support/arg_list.h"
#include "src/__support/macros/config.h"
#include "src/stdio/scanf_core/vfscanf_internal.h"

#include "hdr/types/FILE.h"
#include <stdarg.h>

namespace LIBC_NAMESPACE_DECL {

LLVM_LIBC_FUNCTION(int, fscanf,
                   (::FILE *__restrict stream, const char *__restrict format,
                    ...)) {
  va_list vlist;
  va_start(vlist, format);
  internal::ArgList args(vlist); // This holder class allows for easier copying
                                 // and pointer semantics, as well as handling
                                 // destruction automatically.
  va_end(vlist);
  int ret_val = scanf_core::vfscanf_internal(stream, format, args);
  // This is done to avoid including stdio.h in the internals. On most systems
  // EOF is -1, so this will be transformed into just "return ret_val".
  return (ret_val == -1) ? EOF : ret_val;
}

} // namespace LIBC_NAMESPACE_DECL

#ifdef LIBC_COPT_SCANF_PROVIDE_ISOC99_ALIASES
LLVM_LIBC_ADD_FUNCTION_C_ALIAS(fscanf, __isoc99_fscanf);
#endif // LIBC_COPT_SCANF_PROVIDE_ISOC99_ALIASES