support/xread.c

   1 /* read with error checking and retries.
   2    Copyright (C) 2023-2024 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 #include <support/xunistd.h>
  20
  21 #include <support/check.h>
  22
  23 void
  24 xread (int fd, void *buffer, size_t length)
  25 {
  26   char *p = buffer;
  27   char *end = p + length;
  28   while (p < end)
  29     {
  30       ssize_t ret = read (fd, p, end - p);
  31       if (ret < 0)
  32         FAIL_EXIT1 ("read of %zu bytes failed after %td: %m",
  33                     length, p - (char *) buffer);
  34       p += ret;
  35     }
  36 }