stdio-common/wprintf_buffer_to_file.c

   1 /* Wide printf buffers writing data to a FILE *.
   2    Copyright (C) 2022-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 /* This implementation is not optimized (unlikely the multibyte
  20    implementation) and always writes to the temporary buffer first.  */
  21
  22 #include <printf_buffer_to_file.h>
  23
  24 #include <array_length.h>
  25 #include <libio/libioP.h>
  26
  27 void
  28 __wprintf_buffer_flush_to_file (struct __wprintf_buffer_to_file *buf)
  29 {
  30   size_t count = buf->base.write_ptr - buf->stage;
  31   if ((size_t) _IO_sputn (buf->fp, buf->stage, count) != count)
  32     {
  33       __wprintf_buffer_mark_failed (&buf->base);
  34       return;
  35     }
  36   buf->base.written += count;
  37   buf->base.write_ptr = buf->stage;
  38 }
  39
  40 void
  41 __wprintf_buffer_to_file_init (struct __wprintf_buffer_to_file *buf, FILE *fp)
  42 {
  43   __wprintf_buffer_init (&buf->base, buf->stage, array_length (buf->stage),
  44                          __wprintf_buffer_mode_to_file);
  45   buf->fp = fp;
  46 }
  47
  48 int
  49 __wprintf_buffer_to_file_done (struct __wprintf_buffer_to_file *buf)
  50 {
  51   if (__wprintf_buffer_has_failed (&buf->base))
  52     return -1;
  53   __wprintf_buffer_flush_to_file (buf);
  54   return __wprintf_buffer_done (&buf->base);
  55 }