42 lines · cpp
1//===-- Implementation of scanf ---------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "src/stdio/scanf.h"10 11#include "src/__support/File/file.h"12#include "src/__support/arg_list.h"13#include "src/__support/macros/config.h"14#include "src/stdio/scanf_core/vfscanf_internal.h"15 16#include "hdr/types/FILE.h"17#include <stdarg.h>18 19#ifndef LIBC_COPT_STDIO_USE_SYSTEM_FILE20#define SCANF_STDIN LIBC_NAMESPACE::stdin21#else // LIBC_COPT_STDIO_USE_SYSTEM_FILE22#define SCANF_STDIN ::stdin23#endif // LIBC_COPT_STDIO_USE_SYSTEM_FILE24 25namespace LIBC_NAMESPACE_DECL {26 27LLVM_LIBC_FUNCTION(int, scanf, (const char *__restrict format, ...)) {28 va_list vlist;29 va_start(vlist, format);30 internal::ArgList args(vlist); // This holder class allows for easier copying31 // and pointer semantics, as well as handling32 // destruction automatically.33 va_end(vlist);34 int ret_val = scanf_core::vfscanf_internal(35 reinterpret_cast<::FILE *>(SCANF_STDIN), format, args);36 // This is done to avoid including stdio.h in the internals. On most systems37 // EOF is -1, so this will be transformed into just "return ret_val".38 return (ret_val == -1) ? EOF : ret_val;39}40 41} // namespace LIBC_NAMESPACE_DECL42