libc/src/stdio/generic/vscanf.cpp

//===-- Implementation of vscanf --------------------------------*- 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/vscanf.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 "src/stdio/stdin.h"

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

#ifndef LIBC_COPT_STDIO_USE_SYSTEM_FILE
#define SCANF_STDIN LIBC_NAMESPACE::stdin
#else // LIBC_COPT_STDIO_USE_SYSTEM_FILE
#define SCANF_STDIN ::stdin
#endif // LIBC_COPT_STDIO_USE_SYSTEM_FILE

namespace LIBC_NAMESPACE_DECL {

LLVM_LIBC_FUNCTION(int, vscanf,
                   (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.
  va_end(vlist);
  int ret_val = scanf_core::vfscanf_internal(
      reinterpret_cast<::FILE *>(SCANF_STDIN), 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(vscanf, __isoc99_vscanf);
#endif // LIBC_COPT_SCANF_PROVIDE_ISOC99_ALIASES