/* Check two strings for equality.

   Copyright (C) 2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <support/check.h>

#include <support/support.h>

#include <support/xmemstream.h>

static void

report_length (const char *what, const char *str, size_t length)

{

  if (str == NULL)

    printf ("  %s string: NULL\n", what);

  else

    printf ("  %s string: %zu bytes\n", what, length);

}

static void

report_string (const char *what, const unsigned char *blob,

               size_t length, const char *expr)

{

  if (length > 0)

    {

      printf ("  %s (evaluated from %s):\n", what, expr);

      char *quoted = support_quote_blob (blob, length);

      printf ("      \"%s\"\n", quoted);

      free (quoted);

      fputs ("     ", stdout);

      for (size_t i = 0; i < length; ++i)

        printf (" %02X", blob[i]);

      putc ('\n', stdout);

    }

}

static size_t

string_length_or_zero (const char *str)

{

  if (str == NULL)

    return 0;

  else

    return strlen (str);

}

void

support_test_compare_string (const char *left, const char *right,

                             const char *file, int line,

                             const char *left_expr, const char *right_expr)

{

  /* Two null pointers are accepted.  */

  if (left == NULL && right == NULL)

    return;

  size_t left_length = string_length_or_zero (left);

  size_t right_length = string_length_or_zero (right);

  if (left_length != right_length || left == NULL || right == NULL

      || memcmp (left, right, left_length) != 0)

    {

      support_record_failure ();

      printf ("%s:%d: error: blob comparison failed\n", file, line);

      if (left_length == right_length && right != NULL && left != NULL)

        printf ("  string length: %zu bytes\n", left_length);

      else

        {

          report_length ("left", left, left_length);

          report_length ("right", right, right_length);

        }

      report_string ("left", (const unsigned char *) left,

                     left_length, left_expr);

      report_string ("right", (const unsigned char *) right,

                     right_length, right_expr);

    }

}