libc/src/stdio/fscanf.cpp

   1 //===-- Implementation of fscanf --------------------------------*- 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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "src/stdio/fscanf.h"
  10
  11 #include "src/__support/File/file.h"
  12 #include "src/__support/arg_list.h"
  13 #include "src/stdio/scanf_core/vfscanf_internal.h"
  14
  15 #include <stdarg.h>
  16 #include <stdio.h>
  17
  18 namespace __llvm_libc {
  19
  20 LLVM_LIBC_FUNCTION(int, fscanf,
  21                    (::FILE *__restrict stream, const char *__restrict format,
  22                     ...)) {
  23   va_list vlist;
  24   va_start(vlist, format);
  25   internal::ArgList args(vlist); // This holder class allows for easier copying
  26                                  // and pointer semantics, as well as handling
  27                                  // destruction automatically.
  28   va_end(vlist);
  29   int ret_val = scanf_core::vfscanf_internal(stream, format, args);
  30   // This is done to avoid including stdio.h in the internals. On most systems
  31   // EOF is -1, so this will be transformed into just "return ret_val".
  32   return (ret_val == -1) ? EOF : ret_val;
  33 }
  34
  35 } // namespace __llvm_libc