libc/src/stdio/fputc.cpp

   1 //===-- Implementation of fputc -------------------------------------------===//
   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/fputc.h"
  10 #include "src/__support/File/file.h"
  11
  12 #include <errno.h>
  13 #include <stdio.h>
  14
  15 namespace __llvm_libc {
  16
  17 LLVM_LIBC_FUNCTION(int, fputc, (int c, ::FILE *stream)) {
  18   unsigned char uc = static_cast<unsigned char>(c);
  19
  20   auto result = reinterpret_cast<__llvm_libc::File *>(stream)->write(&uc, 1);
  21   if (result.has_error())
  22     errno = result.error;
  23   size_t written = result.value;
  24
  25   if (1 != written) {
  26     // The stream should be in an error state in this case.
  27     return EOF;
  28   }
  29   return 0;
  30 }
  31
  32 } // namespace __llvm_libc