mips: FIx clone3 implementation (BZ 31325)

[glibc.git] / string / tester.c

/* Tester for string functions.
   Copyright (C) 1995-2024 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
   <https://www.gnu.org/licenses/>.  */

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

/* Make sure we don't test the optimized inline functions if we want to
   test the real implementation.  */
#if !defined DO_STRING_INLINES
#undef __USE_STRING_INLINES
#endif

#include <sys/cdefs.h>
#include <libc-diag.h>

/* Triggered by strncpy fortify wrapper when it is enabled.  */
#if __GNUC_PREREQ (8, 0)
DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation");
#endif

/* When building with fortify enabled, GCC < 12 issues a warning on the
   fortify strncat wrapper might overflow the destination buffer (the
   failure is tied to -Werror).
   Triggered by strncat fortify wrapper when it is enabled.  */
#if __GNUC_PREREQ (11, 0)
DIAG_IGNORE_NEEDS_COMMENT (11, "-Wstringop-overread");
#endif

#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <fcntl.h>

/* This file tests a range of corner cases of string functions,
   including cases where truncation occurs or where sizes specified
   are larger than the actual buffers, which result in various
   warnings.  */
DIAG_IGNORE_NEEDS_COMMENT (8, "-Warray-bounds");
DIAG_IGNORE_NEEDS_COMMENT (5.0, "-Wmemset-transposed-args");
#if __GNUC_PREREQ (7, 0)
DIAG_IGNORE_NEEDS_COMMENT (9, "-Wrestrict");
DIAG_IGNORE_NEEDS_COMMENT (7, "-Wstringop-overflow=");
#endif


#define STREQ(a, b)     (strcmp((a), (b)) == 0)

const char *it = "<UNSET>";     /* Routine name for message routines. */
size_t errors = 0;

/* Complain if condition is not true.  */
static void
check (int thing, int number)
{
  if (!thing)
    {
      printf ("%s flunked test %d\n", it, number);
      ++errors;
    }
}

/* Complain if first two args don't strcmp as equal.  */
static void
equal (const char *a, const char *b, int number)
{
  check (a != NULL && b != NULL && STREQ (a, b), number);
}

char one[50];
char two[50];
char *cp;

static void
test_strcmp (void)
{
  it = "strcmp";
  check (strcmp ("", "") == 0, 1);              /* Trivial case. */
  check (strcmp ("a", "a") == 0, 2);            /* Identity. */
  check (strcmp ("abc", "abc") == 0, 3);        /* Multicharacter. */
  check (strcmp ("abc", "abcd") < 0, 4);        /* Length mismatches. */
  check (strcmp ("abcd", "abc") > 0, 5);
  check (strcmp ("abcd", "abce") < 0, 6);       /* Honest miscompares. */
  check (strcmp ("abce", "abcd") > 0, 7);
  check (strcmp ("a\203", "a") > 0, 8);         /* Tricky if char signed. */
  check (strcmp ("a\203", "a\003") > 0, 9);

  {
    char buf1[0x40], buf2[0x40];
    int i, j;
    for (i=0; i < 0x10; i++)
      for (j = 0; j < 0x10; j++)
        {
          int k;
          for (k = 0; k < 0x3f; k++)
            {
              buf1[k] = '0' ^ (k & 4);
              buf2[k] = '4' ^ (k & 4);
            }
          buf1[i] = buf1[0x3f] = 0;
          buf2[j] = buf2[0x3f] = 0;
          for (k = 0; k < 0xf; k++)
            {
              int cnum = 0x10+0x10*k+0x100*j+0x1000*i;
              check (strcmp (buf1+i,buf2+j) == 0, cnum);
              buf1[i+k] = 'A' + i + k;
              buf1[i+k+1] = 0;
              check (strcmp (buf1+i,buf2+j) > 0, cnum+1);
              check (strcmp (buf2+j,buf1+i) < 0, cnum+2);
              buf2[j+k] = 'B' + i + k;
              buf2[j+k+1] = 0;
              check (strcmp (buf1+i,buf2+j) < 0, cnum+3);
              check (strcmp (buf2+j,buf1+i) > 0, cnum+4);
              buf2[j+k] = 'A' + i + k;
              buf1[i] = 'A' + i + 0x80;
              check (strcmp (buf1+i,buf2+j) > 0, cnum+5);
              check (strcmp (buf2+j,buf1+i) < 0, cnum+6);
              buf1[i] = 'A' + i;
            }
        }
  }
}

#define SIMPLE_COPY(fn, n, str, ntest) \
  do {                                                                        \
    int __n;                                                                  \
    char *cp;                                                                 \
    for (__n = 0; __n < (int) sizeof (one); ++__n)                            \
      one[__n] = 'Z';                                                         \
    fn (one, str);                                                            \
    for (cp = one, __n = 0; __n < n; ++__n, ++cp)                             \
      check (*cp == '0' + (n % 10), ntest);                                   \
    check (*cp == '\0', ntest);                                               \
  } while (0)

static void
test_strcpy (void)
{
  int i;
  it = "strcpy";
  check (strcpy (one, "abcd") == one, 1); /* Returned value. */
  equal (one, "abcd", 2);               /* Basic test. */

  (void) strcpy (one, "x");
  equal (one, "x", 3);                  /* Writeover. */
  equal (one+2, "cd", 4);               /* Wrote too much? */

  (void) strcpy (two, "hi there");
  (void) strcpy (one, two);
  equal (one, "hi there", 5);           /* Basic test encore. */
  equal (two, "hi there", 6);           /* Stomped on source? */

  (void) strcpy (one, "");
  equal (one, "", 7);                   /* Boundary condition. */

  for (i = 0; i < 16; i++)
    {
      (void) strcpy (one + i, "hi there");      /* Unaligned destination. */
      equal (one + i, "hi there", 8 + (i * 2));
      (void) strcpy (two, one + i);             /* Unaligned source. */
      equal (two, "hi there", 9 + (i * 2));
    }

  SIMPLE_COPY(strcpy, 0, "", 41);
  SIMPLE_COPY(strcpy, 1, "1", 42);
  SIMPLE_COPY(strcpy, 2, "22", 43);
  SIMPLE_COPY(strcpy, 3, "333", 44);
  SIMPLE_COPY(strcpy, 4, "4444", 45);
  SIMPLE_COPY(strcpy, 5, "55555", 46);
  SIMPLE_COPY(strcpy, 6, "666666", 47);
  SIMPLE_COPY(strcpy, 7, "7777777", 48);
  SIMPLE_COPY(strcpy, 8, "88888888", 49);
  SIMPLE_COPY(strcpy, 9, "999999999", 50);
  SIMPLE_COPY(strcpy, 10, "0000000000", 51);
  SIMPLE_COPY(strcpy, 11, "11111111111", 52);
  SIMPLE_COPY(strcpy, 12, "222222222222", 53);
  SIMPLE_COPY(strcpy, 13, "3333333333333", 54);
  SIMPLE_COPY(strcpy, 14, "44444444444444", 55);
  SIMPLE_COPY(strcpy, 15, "555555555555555", 56);
  SIMPLE_COPY(strcpy, 16, "6666666666666666", 57);

  /* Simple test using implicitly coerced `void *' arguments.  */
  const void *src = "frobozz";
  void *dst = one;
  check (strcpy (dst, src) == dst, 1);
  equal (dst, "frobozz", 2);
}

static void
test_stpcpy (void)
{
  it = "stpcpy";
  check ((stpcpy (one, "a") - one) == 1, 1);
  equal (one, "a", 2);

  check ((stpcpy (one, "ab") - one) == 2, 3);
  equal (one, "ab", 4);

  check ((stpcpy (one, "abc") - one) == 3, 5);
  equal (one, "abc", 6);

  check ((stpcpy (one, "abcd") - one) == 4, 7);
  equal (one, "abcd", 8);

  check ((stpcpy (one, "abcde") - one) == 5, 9);
  equal (one, "abcde", 10);

  check ((stpcpy (one, "abcdef") - one) == 6, 11);
  equal (one, "abcdef", 12);

  check ((stpcpy (one, "abcdefg") - one) == 7, 13);
  equal (one, "abcdefg", 14);

  check ((stpcpy (one, "abcdefgh") - one) == 8, 15);
  equal (one, "abcdefgh", 16);

  check ((stpcpy (one, "abcdefghi") - one) == 9, 17);
  equal (one, "abcdefghi", 18);

  check ((stpcpy (one, "x") - one) == 1, 19);
  equal (one, "x", 20);                 /* Writeover. */
  equal (one+2, "cdefghi", 21);         /* Wrote too much? */

  check ((stpcpy (one, "xx") - one) == 2, 22);
  equal (one, "xx", 23);                /* Writeover. */
  equal (one+3, "defghi", 24);          /* Wrote too much? */

  check ((stpcpy (one, "xxx") - one) == 3, 25);
  equal (one, "xxx", 26);               /* Writeover. */
  equal (one+4, "efghi", 27);           /* Wrote too much? */

  check ((stpcpy (one, "xxxx") - one) == 4, 28);
  equal (one, "xxxx", 29);              /* Writeover. */
  equal (one+5, "fghi", 30);            /* Wrote too much? */

  check ((stpcpy (one, "xxxxx") - one) == 5, 31);
  equal (one, "xxxxx", 32);             /* Writeover. */
  equal (one+6, "ghi", 33);             /* Wrote too much? */

  check ((stpcpy (one, "xxxxxx") - one) == 6, 34);
  equal (one, "xxxxxx", 35);            /* Writeover. */
  equal (one+7, "hi", 36);              /* Wrote too much? */

  check ((stpcpy (one, "xxxxxxx") - one) == 7, 37);
  equal (one, "xxxxxxx", 38);           /* Writeover. */
  equal (one+8, "i", 39);               /* Wrote too much? */

  check ((stpcpy (stpcpy (stpcpy (one, "a"), "b"), "c") - one) == 3, 40);
  equal (one, "abc", 41);
  equal (one + 4, "xxx", 42);

  SIMPLE_COPY(stpcpy, 0, "", 43);
  SIMPLE_COPY(stpcpy, 1, "1", 44);
  SIMPLE_COPY(stpcpy, 2, "22", 45);
  SIMPLE_COPY(stpcpy, 3, "333", 46);
  SIMPLE_COPY(stpcpy, 4, "4444", 47);
  SIMPLE_COPY(stpcpy, 5, "55555", 48);
  SIMPLE_COPY(stpcpy, 6, "666666", 49);
  SIMPLE_COPY(stpcpy, 7, "7777777", 50);
  SIMPLE_COPY(stpcpy, 8, "88888888", 51);
  SIMPLE_COPY(stpcpy, 9, "999999999", 52);
  SIMPLE_COPY(stpcpy, 10, "0000000000", 53);
  SIMPLE_COPY(stpcpy, 11, "11111111111", 54);
  SIMPLE_COPY(stpcpy, 12, "222222222222", 55);
  SIMPLE_COPY(stpcpy, 13, "3333333333333", 56);
  SIMPLE_COPY(stpcpy, 14, "44444444444444", 57);
  SIMPLE_COPY(stpcpy, 15, "555555555555555", 58);
  SIMPLE_COPY(stpcpy, 16, "6666666666666666", 59);
}

static void
test_stpncpy (void)
{
  it = "stpncpy";
  memset (one, 'x', sizeof (one));
  check (stpncpy (one, "abc", 2) == one + 2, 1);
  check (stpncpy (one, "abc", 3) == one + 3, 2);
  check (stpncpy (one, "abc", 4) == one + 3, 3);
  check (one[3] == '\0' && one[4] == 'x', 4);
  check (stpncpy (one, "abcd", 5) == one + 4, 5);
  check (one[4] == '\0' && one[5] == 'x', 6);
  check (stpncpy (one, "abcd", 6) == one + 4, 7);
  check (one[4] == '\0' && one[5] == '\0' && one[6] == 'x', 8);
}

static void
test_strcat (void)
{
  it = "strcat";
  (void) strcpy (one, "ijk");
  check (strcat (one, "lmn") == one, 1); /* Returned value. */
  equal (one, "ijklmn", 2);             /* Basic test. */

  (void) strcpy (one, "x");
  (void) strcat (one, "yz");
  equal (one, "xyz", 3);                        /* Writeover. */
  equal (one+4, "mn", 4);                       /* Wrote too much? */

  (void) strcpy (one, "gh");
  (void) strcpy (two, "ef");
  (void) strcat (one, two);
  equal (one, "ghef", 5);                       /* Basic test encore. */
  equal (two, "ef", 6);                 /* Stomped on source? */

  (void) strcpy (one, "");
  (void) strcat (one, "");
  equal (one, "", 7);                   /* Boundary conditions. */
  (void) strcpy (one, "ab");
  (void) strcat (one, "");
  equal (one, "ab", 8);
  (void) strcpy (one, "");
  (void) strcat (one, "cd");
  equal (one, "cd", 9);

  int ntest = 10;
  char buf1[80] __attribute__ ((aligned (16)));
  char buf2[32] __attribute__ ((aligned (16)));
  for (size_t n1 = 0; n1 < 16; ++n1)
    for (size_t n2 = 0; n2 < 16; ++n2)
      for (size_t n3 = 0; n3 < 32; ++n3)
        {
          size_t olderrors = errors;

          memset (buf1, 'b', sizeof (buf1));

          memset (buf1 + n2, 'a', n3);
          buf1[n2 + n3] = '\0';
          strcpy (buf2 + n1, "123");

          check (strcat (buf1 + n2, buf2 + n1) == buf1 + n2, ntest);
          if (errors == olderrors)
            for (size_t i = 0; i < sizeof (buf1); ++i)
              {
                if (i < n2)
                  check (buf1[i] == 'b', ntest);
                else if (i < n2 + n3)
                  check (buf1[i] == 'a', ntest);
                else if (i < n2 + n3 + 3)
                  check (buf1[i] == "123"[i - (n2 + n3)], ntest);
                else if (i == n2 + n3 + 3)
                  check (buf1[i] == '\0', ntest);
                else
                  check (buf1[i] == 'b', ntest);

                if (errors != olderrors)
                  {
                    printf ("n1=%zu, n2=%zu, n3=%zu, buf1=%02hhx",
                            n1, n2, n3, buf1[0]);
                    for (size_t j = 1; j < sizeof (buf1); ++j)
                      printf (",%02hhx", buf1[j]);
                    putchar_unlocked ('\n');
                    break;
                  }
              }
        }
}

static void
test_strncat (void)
{
  /* First test it as strcat, with big counts, then test the count
     mechanism.  */
  it = "strncat";
  (void) strcpy (one, "ijk");
  check (strncat (one, "lmn", 99) == one, 1);   /* Returned value. */
  equal (one, "ijklmn", 2);             /* Basic test. */

  (void) strcpy (one, "x");
  (void) strncat (one, "yz", 99);
  equal (one, "xyz", 3);                /* Writeover. */
  equal (one+4, "mn", 4);               /* Wrote too much? */

  (void) strcpy (one, "gh");
  (void) strcpy (two, "ef");
  /* When building with fortify enabled, GCC 6 issues an warning the fortify
     wrapper might overflow the destination buffer.  However, GCC does not
     provide a specific flag to disable the warning (the failure is tied to
     -Werror).  So to avoid disable all errors, only enable the check for
     GCC 7 or newer.  */
#if __GNUC_PREREQ (7, 0)
  (void) strncat (one, two, 99);
  equal (one, "ghef", 5);                       /* Basic test encore. */
#else
  equal (one, "gh", 2);
#endif
  equal (two, "ef", 6);                 /* Stomped on source? */

  (void) strcpy (one, "");
  (void) strncat (one, "", 99);
  equal (one, "", 7);                   /* Boundary conditions. */
  (void) strcpy (one, "ab");
  (void) strncat (one, "", 99);
  equal (one, "ab", 8);
  (void) strcpy (one, "");
  (void) strncat (one, "cd", 99);
  equal (one, "cd", 9);

  (void) strcpy (one, "ab");
  (void) strncat (one, "cdef", 2);
  equal (one, "abcd", 10);                      /* Count-limited. */

  (void) strncat (one, "gh", 0);
  equal (one, "abcd", 11);                      /* Zero count. */

  (void) strncat (one, "gh", 2);
  equal (one, "abcdgh", 12);            /* Count and length equal. */

  (void) strncat (one, "ij", (size_t)-1);       /* set sign bit in count */
  equal (one, "abcdghij", 13);

  int ntest = 14;
  char buf1[80] __attribute__ ((aligned (16)));
  char buf2[32] __attribute__ ((aligned (16)));
  for (size_t n1 = 0; n1 < 16; ++n1)
    for (size_t n2 = 0; n2 < 16; ++n2)
      for (size_t n3 = 0; n3 < 32; ++n3)
        for (size_t n4 = 0; n4 < 16; ++n4)
          {
            size_t olderrors = errors;

            memset (buf1, 'b', sizeof (buf1));

            memset (buf1 + n2, 'a', n3);
            buf1[n2 + n3] = '\0';
            strcpy (buf2 + n1, "123");

            check (strncat (buf1 + n2, buf2 + n1, ~((size_t) 0) - n4)
                   == buf1 + n2, ntest);
            if (errors == olderrors)
              for (size_t i = 0; i < sizeof (buf1); ++i)
                {
                  if (i < n2)
                    check (buf1[i] == 'b', ntest);
                  else if (i < n2 + n3)
                    check (buf1[i] == 'a', ntest);
                  else if (i < n2 + n3 + 3)
                    check (buf1[i] == "123"[i - (n2 + n3)], ntest);
                  else if (i == n2 + n3 + 3)
                    check (buf1[i] == '\0', ntest);
                  else
                    check (buf1[i] == 'b', ntest);

                  if (errors != olderrors)
                    {
                      printf ("n1=%zu, n2=%zu, n3=%zu, n4=%zu, buf1=%02hhx",
                              n1, n2, n3, n4, buf1[0]);
                      for (size_t j = 1; j < sizeof (buf1); ++j)
                        printf (",%02hhx", buf1[j]);
                      putchar_unlocked ('\n');
                      break;
                    }
                }
          }
}

static void
test_strncmp (void)
{
  /* First test as strcmp with big counts, then test count code.  */
  it = "strncmp";
  check (strncmp ("", "", 99) == 0, 1); /* Trivial case. */
  check (strncmp ("a", "a", 99) == 0, 2);       /* Identity. */
  check (strncmp ("abc", "abc", 99) == 0, 3);   /* Multicharacter. */
  check (strncmp ("abc", "abcd", 99) < 0, 4);   /* Length unequal. */
  check (strncmp ("abcd", "abc", 99) > 0, 5);
  check (strncmp ("abcd", "abce", 99) < 0, 6);  /* Honestly unequal. */
  check (strncmp ("abce", "abcd", 99) > 0, 7);
  check (strncmp ("a\203", "a", 2) > 0, 8);     /* Tricky if '\203' < 0 */
  check (strncmp ("a\203", "a\003", 2) > 0, 9);
  check (strncmp ("abce", "abcd", 3) == 0, 10); /* Count limited. */
  check (strncmp ("abce", "abc", 3) == 0, 11);  /* Count == length. */
  check (strncmp ("abcd", "abce", 4) < 0, 12);  /* Nudging limit. */
  check (strncmp ("abc", "def", 0) == 0, 13);   /* Zero count. */
  check (strncmp ("abc", "", (size_t)-1) > 0, 14);      /* set sign bit in count */
  check (strncmp ("abc", "abc", (size_t)-2) == 0, 15);
}

static void
test_strncpy (void)
{
  /* Testing is a bit different because of odd semantics.  */
  it = "strncpy";
  check (strncpy (one, "abc", 4) == one, 1);    /* Returned value. */
  equal (one, "abc", 2);                        /* Did the copy go right? */

  (void) strcpy (one, "abcdefgh");
  (void) strncpy (one, "xyz", 2);
  equal (one, "xycdefgh", 3);                   /* Copy cut by count. */

  (void) strcpy (one, "abcdefgh");
  (void) strncpy (one, "xyz", 3);               /* Copy cut just before NUL. */
  equal (one, "xyzdefgh", 4);

  (void) strcpy (one, "abcdefgh");
  (void) strncpy (one, "xyz", 4);               /* Copy just includes NUL. */
  equal (one, "xyz", 5);
  equal (one+4, "efgh", 6);                     /* Wrote too much? */

  (void) strcpy (one, "abcdefgh");
  (void) strncpy (one, "xyz", 5);               /* Copy includes padding. */
  equal (one, "xyz", 7);
  equal (one+4, "", 8);
  equal (one+5, "fgh", 9);

  (void) strcpy (one, "abc");
  (void) strncpy (one, "xyz", 0);               /* Zero-length copy. */
  equal (one, "abc", 10);

  (void) strncpy (one, "", 2);          /* Zero-length source. */
  equal (one, "", 11);
  equal (one+1, "", 12);
  equal (one+2, "c", 13);

  (void) strcpy (one, "hi there");
  (void) strncpy (two, one, 9);
  equal (two, "hi there", 14);          /* Just paranoia. */
  equal (one, "hi there", 15);          /* Stomped on source? */
}

static void
test_strlen (void)
{
  it = "strlen";
  check (strlen ("") == 0, 1);          /* Empty. */
  check (strlen ("a") == 1, 2);         /* Single char. */
  check (strlen ("abcd") == 4, 3);      /* Multiple chars. */
  {
    char buf[4096];
    int i;
    char *p;
    for (i=0; i < 0x100; i++)
      {
        p = (char *) ((uintptr_t)(buf + 0xff) & ~0xff) + i;
        strcpy (p, "OK");
        strcpy (p+3, "BAD/WRONG");
        check (strlen (p) == 2, 4+i);
      }
   }
}

static void
test_strnlen (void)
{
  it = "strnlen";
  check (strnlen ("", 10) == 0, 1);             /* Empty. */
  check (strnlen ("a", 10) == 1, 2);            /* Single char. */
  check (strnlen ("abcd", 10) == 4, 3);         /* Multiple chars. */
  check (strnlen ("foo", (size_t) -1) == 3, 4); /* limits of n. */
  check (strnlen ("abcd", 0) == 0, 5);          /* Restricted. */
  check (strnlen ("abcd", 1) == 1, 6);          /* Restricted. */
  check (strnlen ("abcd", 2) == 2, 7);          /* Restricted. */
  check (strnlen ("abcd", 3) == 3, 8);          /* Restricted. */
  check (strnlen ("abcd", 4) == 4, 9);          /* Restricted. */

  char buf[4096];
  for (int i = 0; i < 0x100; ++i)
    {
      char *p = (char *) ((uintptr_t)(buf + 0xff) & ~0xff) + i;
      strcpy (p, "OK");
      strcpy (p + 3, "BAD/WRONG");
      check (strnlen (p, 100) == 2, 10 + i);
    }
}

static void
test_strchr (void)
{
  it = "strchr";
  check (strchr ("abcd", 'z') == NULL, 1);      /* Not found. */
  (void) strcpy (one, "abcd");
  check (strchr (one, 'c') == one+2, 2);        /* Basic test. */
  check (strchr (one, 'd') == one+3, 3);        /* End of string. */
  check (strchr (one, 'a') == one, 4);          /* Beginning. */
  check (strchr (one, '\0') == one+4, 5);       /* Finding NUL. */
  (void) strcpy (one, "ababa");
  check (strchr (one, 'b') == one+1, 6);        /* Finding first. */
  (void) strcpy (one, "");
  check (strchr (one, 'b') == NULL, 7);         /* Empty string. */
  check (strchr (one, '\0') == one, 8);         /* NUL in empty string. */
  {
    char buf[4096];
    int i;
    char *p;
    for (i=0; i < 0x100; i++)
      {
        p = (char *) ((uintptr_t) (buf + 0xff) & ~0xff) + i;
        strcpy (p, "OK");
        strcpy (p+3, "BAD/WRONG");
        check (strchr (p, '/') == NULL, 9+i);
      }
   }
}

static void
test_strchrnul (void)
{
  const char *os;
  it = "strchrnul";
  cp = strchrnul ((os = "abcd"), 'z');
  check (*cp == '\0', 1);                       /* Not found. */
  check (cp == os + 4, 2);
  (void) strcpy (one, "abcd");
  check (strchrnul (one, 'c') == one+2, 3);     /* Basic test. */
  check (strchrnul (one, 'd') == one+3, 4);     /* End of string. */
  check (strchrnul (one, 'a') == one, 5);       /* Beginning. */
  check (strchrnul (one, '\0') == one+4, 6);    /* Finding NUL. */
  (void) strcpy (one, "ababa");
  check (strchrnul (one, 'b') == one+1, 7);     /* Finding first. */
  (void) strcpy (one, "");
  check (strchrnul (one, 'b') == one, 8);       /* Empty string. */
  check (strchrnul (one, '\0') == one, 9);      /* NUL in empty string. */
  {
    char buf[4096];
    int i;
    char *p;
    for (i=0; i < 0x100; i++)
      {
        p = (char *) ((uintptr_t) (buf + 0xff) & ~0xff) + i;
        strcpy (p, "OK");
        strcpy (p+3, "BAD/WRONG");
        cp = strchrnul (p, '/');
        check (*cp == '\0', 9+2*i);
        check (cp == p+2, 10+2*i);
      }
   }
}

static void
test_rawmemchr (void)
{
  it = "rawmemchr";
  (void) strcpy (one, "abcd");
  check (rawmemchr (one, 'c') == one+2, 1);     /* Basic test. */
  check (rawmemchr (one, 'd') == one+3, 2);     /* End of string. */
  check (rawmemchr (one, 'a') == one, 3);               /* Beginning. */
  check (rawmemchr (one, '\0') == one+4, 4);    /* Finding NUL. */
  (void) strcpy (one, "ababa");
  check (rawmemchr (one, 'b') == one+1, 5);     /* Finding first. */
  (void) strcpy (one, "");
  check (rawmemchr (one, '\0') == one, 6);      /* NUL in empty string. */
  {
    char buf[4096];
    int i;
    char *p;
    for (i=0; i < 0x100; i++)
      {
        p = (char *) ((uintptr_t) (buf + 0xff) & ~0xff) + i;
        strcpy (p, "OK");
        strcpy (p+3, "BAD/WRONG");
        check (rawmemchr (p, 'R') == p+8, 6+i);
      }
   }
}

static void
test_index (void)
{
  it = "index";
  check (index ("abcd", 'z') == NULL, 1);       /* Not found. */
  (void) strcpy (one, "abcd");
  check (index (one, 'c') == one+2, 2); /* Basic test. */
  check (index (one, 'd') == one+3, 3); /* End of string. */
  check (index (one, 'a') == one, 4);   /* Beginning. */
  check (index (one, '\0') == one+4, 5);        /* Finding NUL. */
  (void) strcpy (one, "ababa");
  check (index (one, 'b') == one+1, 6); /* Finding first. */
  (void) strcpy (one, "");
  check (index (one, 'b') == NULL, 7);  /* Empty string. */
  check (index (one, '\0') == one, 8);  /* NUL in empty string. */
}

static void
test_strrchr (void)
{
  it = "strrchr";
  check (strrchr ("abcd", 'z') == NULL, 1);     /* Not found. */
  (void) strcpy (one, "abcd");
  check (strrchr (one, 'c') == one+2, 2);       /* Basic test. */
  check (strrchr (one, 'd') == one+3, 3);       /* End of string. */
  check (strrchr (one, 'a') == one, 4);         /* Beginning. */
  check (strrchr (one, '\0') == one+4, 5);      /* Finding NUL. */
  (void) strcpy (one, "ababa");
  check (strrchr (one, 'b') == one+3, 6);       /* Finding last. */
  (void) strcpy (one, "");
  check (strrchr (one, 'b') == NULL, 7);        /* Empty string. */
  check (strrchr (one, '\0') == one, 8);        /* NUL in empty string. */
  {
    char buf[4096];
    int i;
    char *p;
    for (i=0; i < 0x100; i++)
      {
        p = (char *) ((uintptr_t) (buf + 0xff) & ~0xff) + i;
        strcpy (p, "OK");
        strcpy (p+3, "BAD/WRONG");
        check (strrchr (p, '/') == NULL, 9+i);
      }
   }
}

static void
test_memrchr (void)
{
  size_t l;
  it = "memrchr";
  check (memrchr ("abcd", 'z', 5) == NULL, 1);  /* Not found. */
  (void) strcpy (one, "abcd");
  l = strlen (one) + 1;
  check (memrchr (one, 'c', l) == one+2, 2);    /* Basic test. */
  check (memrchr (one, 'd', l) == one+3, 3);    /* End of string. */
  check (memrchr (one, 'a', l) == one, 4);              /* Beginning. */
  check (memrchr (one, '\0', l) == one+4, 5);   /* Finding NUL. */
  (void) strcpy (one, "ababa");
  l = strlen (one) + 1;
  check (memrchr (one, 'b', l) == one+3, 6);    /* Finding last. */
  (void) strcpy (one, "");
  l = strlen (one) + 1;
  check (memrchr (one, 'b', l) == NULL, 7);     /* Empty string. */
  check (memrchr (one, '\0', l) == one, 8);     /* NUL in empty string. */

  /* now test all possible alignment and length combinations to catch
     bugs due to unrolled loops (assuming unrolling is limited to no
     more than 128 byte chunks: */
  {
    char buf[128 + sizeof (long)];
    long align, len, i, pos, n = 9;

    for (align = 0; align < (long) sizeof (long); ++align) {
      for (len = 0; len < (long) (sizeof (buf) - align); ++len) {
        for (i = 0; i < len; ++i)
          buf[align + i] = 'x';         /* don't depend on memset... */

        for (pos = len - 1; pos >= 0; --pos) {
#if 0
          printf("align %d, len %d, pos %d\n", align, len, pos);
#endif
          check(memrchr(buf + align, 'x', len) == buf + align + pos, n++);
          check(memrchr(buf + align + pos + 1, 'x', len - (pos + 1)) == NULL,
                n++);
          buf[align + pos] = '-';
        }
      }
    }
  }
}

static void
test_rindex (void)
{
  it = "rindex";
  check (rindex ("abcd", 'z') == NULL, 1);      /* Not found. */
  (void) strcpy (one, "abcd");
  check (rindex (one, 'c') == one+2, 2);        /* Basic test. */
  check (rindex (one, 'd') == one+3, 3);        /* End of string. */
  check (rindex (one, 'a') == one, 4);  /* Beginning. */
  check (rindex (one, '\0') == one+4, 5);       /* Finding NUL. */
  (void) strcpy (one, "ababa");
  check (rindex (one, 'b') == one+3, 6);        /* Finding last. */
  (void) strcpy (one, "");
  check (rindex (one, 'b') == NULL, 7); /* Empty string. */
  check (rindex (one, '\0') == one, 8); /* NUL in empty string. */
}

static void
test_strpbrk (void)
{
  it = "strpbrk";
  check(strpbrk("abcd", "z") == NULL, 1);       /* Not found. */
  (void) strcpy(one, "abcd");
  check(strpbrk(one, "c") == one+2, 2); /* Basic test. */
  check(strpbrk(one, "d") == one+3, 3); /* End of string. */
  check(strpbrk(one, "a") == one, 4);   /* Beginning. */
  check(strpbrk(one, "") == NULL, 5);   /* Empty search list. */
  check(strpbrk(one, "cb") == one+1, 6);        /* Multiple search. */
  (void) strcpy(one, "abcabdea");
  check(strpbrk(one, "b") == one+1, 7); /* Finding first. */
  check(strpbrk(one, "cb") == one+1, 8);        /* With multiple search. */
  check(strpbrk(one, "db") == one+1, 9);        /* Another variant. */
  (void) strcpy(one, "");
  check(strpbrk(one, "bc") == NULL, 10);        /* Empty string. */
  (void) strcpy(one, "");
  check(strpbrk(one, "bcd") == NULL, 11);       /* Empty string. */
  (void) strcpy(one, "");
  check(strpbrk(one, "bcde") == NULL, 12);      /* Empty string. */
  check(strpbrk(one, "") == NULL, 13);  /* Both strings empty. */
  (void) strcpy(one, "abcabdea");
  check(strpbrk(one, "befg") == one+1, 14);     /* Finding first. */
  check(strpbrk(one, "cbr") == one+1, 15);      /* With multiple search. */
  check(strpbrk(one, "db") == one+1, 16);       /* Another variant. */
  check(strpbrk(one, "efgh") == one+6, 17);     /* And yet another. */
}

static void
test_strstr (void)
{
  it = "strstr";
  check(strstr("abcd", "z") == NULL, 1);        /* Not found. */
  check(strstr("abcd", "abx") == NULL, 2);      /* Dead end. */
  (void) strcpy(one, "abcd");
  check(strstr(one, "c") == one+2, 3);  /* Basic test. */
  check(strstr(one, "bc") == one+1, 4); /* Multichar. */
  check(strstr(one, "d") == one+3, 5);  /* End of string. */
  check(strstr(one, "cd") == one+2, 6); /* Tail of string. */
  check(strstr(one, "abc") == one, 7);  /* Beginning. */
  check(strstr(one, "abcd") == one, 8); /* Exact match. */
  check(strstr(one, "abcde") == NULL, 9);       /* Too long. */
  check(strstr(one, "de") == NULL, 10); /* Past end. */
  check(strstr(one, "") == one, 11);    /* Finding empty. */
  (void) strcpy(one, "ababa");
  check(strstr(one, "ba") == one+1, 12);        /* Finding first. */
  (void) strcpy(one, "");
  check(strstr(one, "b") == NULL, 13);  /* Empty string. */
  check(strstr(one, "") == one, 14);    /* Empty in empty string. */
  (void) strcpy(one, "bcbca");
  check(strstr(one, "bca") == one+2, 15);       /* False start. */
  (void) strcpy(one, "bbbcabbca");
  check(strstr(one, "bbca") == one+1, 16);      /* With overlap. */
}

static void
test_strspn (void)
{
  it = "strspn";
  check(strspn("abcba", "abc") == 5, 1);        /* Whole string. */
  check(strspn("abcba", "ab") == 2, 2); /* Partial. */
  check(strspn("abc", "qx") == 0, 3);   /* None. */
  check(strspn("", "ab") == 0, 4);      /* Null string. */
  check(strspn("abc", "") == 0, 5);     /* Null search list. */
}

static void
test_strcspn (void)
{
  it = "strcspn";
  check(strcspn("abcba", "qx") == 5, 1);        /* Whole string. */
  check(strcspn("abcba", "cx") == 2, 2);        /* Partial. */
  check(strcspn("abc", "abc") == 0, 3); /* None. */
  check(strcspn("", "ab") == 0, 4);     /* Null string. */
  check(strcspn("abc", "") == 3, 5);    /* Null search list. */
}

static void
test_strtok (void)
{
  it = "strtok";
  (void) strcpy(one, "first, second, third");
  equal(strtok(one, ", "), "first", 1); /* Basic test. */
  equal(one, "first", 2);
  equal(strtok((char *)NULL, ", "), "second", 3);
  equal(strtok((char *)NULL, ", "), "third", 4);
  check(strtok((char *)NULL, ", ") == NULL, 5);
  (void) strcpy(one, ", first, ");
  equal(strtok(one, ", "), "first", 6); /* Extra delims, 1 tok. */
  check(strtok((char *)NULL, ", ") == NULL, 7);
  (void) strcpy(one, "1a, 1b; 2a, 2b");
  equal(strtok(one, ", "), "1a", 8);    /* Changing delim lists. */
  equal(strtok((char *)NULL, "; "), "1b", 9);
  equal(strtok((char *)NULL, ", "), "2a", 10);
  (void) strcpy(two, "x-y");
  equal(strtok(two, "-"), "x", 11);     /* New string before done. */
  equal(strtok((char *)NULL, "-"), "y", 12);
  check(strtok((char *)NULL, "-") == NULL, 13);
  (void) strcpy(one, "a,b, c,, ,d");
  equal(strtok(one, ", "), "a", 14);    /* Different separators. */
  equal(strtok((char *)NULL, ", "), "b", 15);
  equal(strtok((char *)NULL, " ,"), "c", 16);   /* Permute list too. */
  equal(strtok((char *)NULL, " ,"), "d", 17);
  check(strtok((char *)NULL, ", ") == NULL, 18);
  check(strtok((char *)NULL, ", ") == NULL, 19);        /* Persistence. */
  (void) strcpy(one, ", ");
  check(strtok(one, ", ") == NULL, 20); /* No tokens. */
  (void) strcpy(one, "");
  check(strtok(one, ", ") == NULL, 21); /* Empty string. */
  (void) strcpy(one, "abc");
  equal(strtok(one, ", "), "abc", 22);  /* No delimiters. */
  check(strtok((char *)NULL, ", ") == NULL, 23);
  (void) strcpy(one, "abc");
  equal(strtok(one, ""), "abc", 24);    /* Empty delimiter list. */
  check(strtok((char *)NULL, "") == NULL, 25);
  (void) strcpy(one, "abcdefgh");
  (void) strcpy(one, "a,b,c");
  equal(strtok(one, ","), "a", 26);     /* Basics again... */
  equal(strtok((char *)NULL, ","), "b", 27);
  equal(strtok((char *)NULL, ","), "c", 28);
  check(strtok((char *)NULL, ",") == NULL, 29);
  equal(one+6, "gh", 30);                       /* Stomped past end? */
  equal(one, "a", 31);                  /* Stomped old tokens? */
  equal(one+2, "b", 32);
  equal(one+4, "c", 33);
}

static void
test_strtok_r (void)
{
  it = "strtok_r";
  (void) strcpy(one, "first, second, third");
  cp = NULL;    /* Always initialize cp to make sure it doesn't point to some old data.  */
  equal(strtok_r(one, ", ", &cp), "first", 1);  /* Basic test. */
  equal(one, "first", 2);
  equal(strtok_r((char *)NULL, ", ", &cp), "second", 3);
  equal(strtok_r((char *)NULL, ", ", &cp), "third", 4);
  check(strtok_r((char *)NULL, ", ", &cp) == NULL, 5);
  (void) strcpy(one, ", first, ");
  cp = NULL;
  equal(strtok_r(one, ", ", &cp), "first", 6);  /* Extra delims, 1 tok. */
  check(strtok_r((char *)NULL, ", ", &cp) == NULL, 7);
  (void) strcpy(one, "1a, 1b; 2a, 2b");
  cp = NULL;
  equal(strtok_r(one, ", ", &cp), "1a", 8);     /* Changing delim lists. */
  equal(strtok_r((char *)NULL, "; ", &cp), "1b", 9);
  equal(strtok_r((char *)NULL, ", ", &cp), "2a", 10);
  (void) strcpy(two, "x-y");
  cp = NULL;
  equal(strtok_r(two, "-", &cp), "x", 11);      /* New string before done. */
  equal(strtok_r((char *)NULL, "-", &cp), "y", 12);
  check(strtok_r((char *)NULL, "-", &cp) == NULL, 13);
  (void) strcpy(one, "a,b, c,, ,d");
  cp = NULL;
  equal(strtok_r(one, ", ", &cp), "a", 14);     /* Different separators. */
  equal(strtok_r((char *)NULL, ", ", &cp), "b", 15);
  equal(strtok_r((char *)NULL, " ,", &cp), "c", 16);    /* Permute list too. */
  equal(strtok_r((char *)NULL, " ,", &cp), "d", 17);
  check(strtok_r((char *)NULL, ", ", &cp) == NULL, 18);
  check(strtok_r((char *)NULL, ", ", &cp) == NULL, 19); /* Persistence. */
  (void) strcpy(one, ", ");
  cp = NULL;
  check(strtok_r(one, ", ", &cp) == NULL, 20);  /* No tokens. */
  (void) strcpy(one, "");
  cp = NULL;
  check(strtok_r(one, ", ", &cp) == NULL, 21);  /* Empty string. */
  check(strtok_r((char *)NULL, ", ", &cp) == NULL, 22); /* Persistence. */
  (void) strcpy(one, "abc");
  cp = NULL;
  equal(strtok_r(one, ", ", &cp), "abc", 23);   /* No delimiters. */
  check(strtok_r((char *)NULL, ", ", &cp) == NULL, 24);
  (void) strcpy(one, "abc");
  cp = NULL;
  equal(strtok_r(one, "", &cp), "abc", 25);     /* Empty delimiter list. */
  check(strtok_r((char *)NULL, "", &cp) == NULL, 26);
  (void) strcpy(one, "abcdefgh");
  (void) strcpy(one, "a,b,c");
  cp = NULL;
  equal(strtok_r(one, ",", &cp), "a", 27);      /* Basics again... */
  equal(strtok_r((char *)NULL, ",", &cp), "b", 28);
  equal(strtok_r((char *)NULL, ",", &cp), "c", 29);
  check(strtok_r((char *)NULL, ",", &cp) == NULL, 30);
  equal(one+6, "gh", 31);                       /* Stomped past end? */
  equal(one, "a", 32);                          /* Stomped old tokens? */
  equal(one+2, "b", 33);
  equal(one+4, "c", 34);
  strcpy (one, ":::");
  cp = NULL;
  check (strtok_r (one, ":", &cp) == NULL, 35); /* Must store pointer in cp. */
  check (strtok_r (NULL, ":", &cp) == NULL, 36);
}

static void
test_strsep (void)
{
  char *ptr;
  it = "strsep";
  cp = strcpy(one, "first, second, third");
  equal(strsep(&cp, ", "), "first", 1); /* Basic test. */
  equal(one, "first", 2);
  equal(strsep(&cp, ", "), "", 3);
  equal(strsep(&cp, ", "), "second", 4);
  equal(strsep(&cp, ", "), "", 5);
  equal(strsep(&cp, ", "), "third", 6);
  check(strsep(&cp, ", ") == NULL, 7);
  cp = strcpy(one, ", first, ");
  equal(strsep(&cp, ", "), "", 8);
  equal(strsep(&cp, ", "), "", 9);
  equal(strsep(&cp, ", "), "first", 10);        /* Extra delims, 1 tok. */
  equal(strsep(&cp, ", "), "", 11);
  equal(strsep(&cp, ", "), "", 12);
  check(strsep(&cp, ", ") == NULL, 13);
  cp = strcpy(one, "1a, 1b; 2a, 2b");
  equal(strsep(&cp, ", "), "1a", 14);   /* Changing delim lists. */
  equal(strsep(&cp, ", "), "", 15);
  equal(strsep(&cp, "; "), "1b", 16);
  equal(strsep(&cp, ", "), "", 17);
  equal(strsep(&cp, ", "), "2a", 18);
  cp = strcpy(two, "x-y");
  equal(strsep(&cp, "-"), "x", 19);     /* New string before done. */
  equal(strsep(&cp, "-"), "y", 20);
  check(strsep(&cp, "-") == NULL, 21);
  cp = strcpy(one, "a,b, c,, ,d ");
  equal(strsep(&cp, ", "), "a", 22);    /* Different separators. */
  equal(strsep(&cp, ", "), "b", 23);
  equal(strsep(&cp, " ,"), "", 24);
  equal(strsep(&cp, " ,"), "c", 25);    /* Permute list too. */
  equal(strsep(&cp, " ,"), "", 26);
  equal(strsep(&cp, " ,"), "", 27);
  equal(strsep(&cp, " ,"), "", 28);
  equal(strsep(&cp, " ,"), "d", 29);
  equal(strsep(&cp, " ,"), "", 30);
  check(strsep(&cp, ", ") == NULL, 31);
  check(strsep(&cp, ", ") == NULL, 32); /* Persistence. */
  cp = strcpy(one, ", ");
  equal(strsep(&cp, ", "), "", 33);
  equal(strsep(&cp, ", "), "", 34);
  equal(strsep(&cp, ", "), "", 35);
  check(strsep(&cp, ", ") == NULL, 36); /* No tokens. */
  cp = strcpy(one, "");
  equal(strsep(&cp, ", "), "", 37);
  check(strsep(&cp, ", ") == NULL, 38); /* Empty string. */
  cp = strcpy(one, "abc");
  equal(strsep(&cp, ", "), "abc", 39);  /* No delimiters. */
  check(strsep(&cp, ", ") == NULL, 40);
  cp = strcpy(one, "abc");
  equal(strsep(&cp, ""), "abc", 41);    /* Empty delimiter list. */
  check(strsep(&cp, "") == NULL, 42);
  (void) strcpy(one, "abcdefgh");
  cp = strcpy(one, "a,b,c");
  equal(strsep(&cp, ","), "a", 43);     /* Basics again... */
  equal(strsep(&cp, ","), "b", 44);
  equal(strsep(&cp, ","), "c", 45);
  check(strsep(&cp, ",") == NULL, 46);
  equal(one+6, "gh", 47);               /* Stomped past end? */
  equal(one, "a", 48);                  /* Stomped old tokens? */
  equal(one+2, "b", 49);
  equal(one+4, "c", 50);

  {
    char text[] = "This,is,a,test";
    char *list = strdupa (text);
    equal (strsep (&list, ","), "This", 51);
    equal (strsep (&list, ","), "is", 52);
    equal (strsep (&list, ","), "a", 53);
    equal (strsep (&list, ","), "test", 54);
    check (strsep (&list, ",") == NULL, 55);
  }

  cp = strcpy(one, "a,b, c,, ,d,");
  equal(strsep(&cp, ","), "a", 56);     /* Different separators. */
  equal(strsep(&cp, ","), "b", 57);
  equal(strsep(&cp, ","), " c", 58);    /* Permute list too. */
  equal(strsep(&cp, ","), "", 59);
  equal(strsep(&cp, ","), " ", 60);
  equal(strsep(&cp, ","), "d", 61);
  equal(strsep(&cp, ","), "", 62);
  check(strsep(&cp, ",") == NULL, 63);
  check(strsep(&cp, ",") == NULL, 64);  /* Persistence. */

  cp = strcpy(one, "a,b, c,, ,d,");
  equal(strsep(&cp, "xy,"), "a", 65);   /* Different separators. */
  equal(strsep(&cp, "x,y"), "b", 66);
  equal(strsep(&cp, ",xy"), " c", 67);  /* Permute list too. */
  equal(strsep(&cp, "xy,"), "", 68);
  equal(strsep(&cp, "x,y"), " ", 69);
  equal(strsep(&cp, ",xy"), "d", 70);
  equal(strsep(&cp, "xy,"), "", 71);
  check(strsep(&cp, "x,y") == NULL, 72);
  check(strsep(&cp, ",xy") == NULL, 73);        /* Persistence. */

  cp = strcpy(one, "ABC");
  one[4] = ':';
  equal(strsep(&cp, "C"), "AB", 74);    /* Access beyond NUL.  */
  ptr = strsep(&cp, ":");
  equal(ptr, "", 75);
  check(ptr == one + 3, 76);
  check(cp == NULL, 77);

  cp = strcpy(one, "ABC");
  one[4] = ':';
  equal(strsep(&cp, "CD"), "AB", 78);   /* Access beyond NUL.  */
  ptr = strsep(&cp, ":.");
  equal(ptr, "", 79);
  check(ptr == one + 3, 80);

  cp = strcpy(one, "ABC");              /* No token in string.  */
  equal(strsep(&cp, ","), "ABC", 81);
  check(cp == NULL, 82);

  *one = '\0';                          /* Empty string. */
  cp = one;
  ptr = strsep(&cp, ",");
  equal(ptr, "", 83);
  check(ptr == one, 84);
  check(cp == NULL, 85);

  *one = '\0';                          /* Empty string and no token. */
  cp = one;
  ptr = strsep(&cp, "");
  equal(ptr, "", 86);
  check(ptr == one , 87);
  check(cp == NULL, 88);
}

static void
test_memcmp (void)
{
  int cnt = 1;
  char one[21];
  char two[21];

  it = "memcmp";
  check(memcmp("a", "a", 1) == 0, cnt++);       /* Identity. */
  check(memcmp("abc", "abc", 3) == 0, cnt++);   /* Multicharacter. */
  check(memcmp("abcd", "abcf", 4) < 0, cnt++);  /* Honestly unequal. */
  check(memcmp("abcf", "abcd", 4) > 0, cnt++);
  check(memcmp("alph", "cold", 4) < 0, cnt++);
  check(memcmp("a\203", "a\003", 2) > 0, cnt++);
  check(memcmp("a\003", "a\203", 2) < 0, cnt++);
  check(memcmp("a\003bc", "a\203bc", 2) < 0, cnt++);
  check(memcmp("abc\203", "abc\003", 4) > 0, cnt++);
  check(memcmp("abc\003", "abc\203", 4) < 0, cnt++);
  check(memcmp("abcf", "abcd", 3) == 0, cnt++); /* Count limited. */
  check(memcmp("abc", "def", 0) == 0, cnt++);   /* Zero count. */
  /* Comparisons with shifting 4-byte boundaries. */
  for (int i = 0; i < 4; ++i)
    {
      char *a = one + i;
      char *b = two + i;
      memcpy(a, "--------11112222", 16);
      memcpy(b, "--------33334444", 16);
      check(memcmp(b, a, 16) > 0, cnt++);
      check(memcmp(a, b, 16) < 0, cnt++);
    }
}

static void
test_memchr (void)
{
  it = "memchr";
  check(memchr("abcd", 'z', 4) == NULL, 1);     /* Not found. */
  (void) strcpy(one, "abcd");
  check(memchr(one, 'c', 4) == one+2, 2);       /* Basic test. */
  check(memchr(one, ~0xff|'c', 4) == one+2, 2); /* ignore highorder bits. */
  check(memchr(one, 'd', 4) == one+3, 3);       /* End of string. */
  check(memchr(one, 'a', 4) == one, 4); /* Beginning. */
  check(memchr(one, '\0', 5) == one+4, 5);      /* Finding NUL. */
  (void) strcpy(one, "ababa");
  check(memchr(one, 'b', 5) == one+1, 6);       /* Finding first. */
  check(memchr(one, 'b', 0) == NULL, 7);        /* Zero count. */
  check(memchr(one, 'a', 1) == one, 8); /* Singleton case. */
  (void) strcpy(one, "a\203b");
  check(memchr(one, 0203, 3) == one+1, 9);      /* Unsignedness. */

  /* now test all possible alignment and length combinations to catch
     bugs due to unrolled loops (assuming unrolling is limited to no
     more than 128 byte chunks: */
  {
    char buf[128 + sizeof (long)];
    long align, len, i, pos;

    for (align = 0; align < (long) sizeof (long); ++align) {
      for (len = 0; len < (long) (sizeof (buf) - align); ++len) {
        for (i = 0; i < len; ++i) {
          buf[align + i] = 'x';         /* don't depend on memset... */
        }
        for (pos = 0; pos < len; ++pos) {
#if 0
          printf("align %d, len %d, pos %d\n", align, len, pos);
#endif
          check(memchr(buf + align, 'x', len) == buf + align + pos, 10);
          check(memchr(buf + align, 'x', pos) == NULL, 11);
          buf[align + pos] = '-';
        }
      }
    }
  }
}

static void
test_memcpy (void)
{
  int i;
  it = "memcpy";
  check(memcpy(one, "abc", 4) == one, 1);       /* Returned value. */
  equal(one, "abc", 2);                 /* Did the copy go right? */

  (void) strcpy(one, "abcdefgh");
  (void) memcpy(one+1, "xyz", 2);
  equal(one, "axydefgh", 3);            /* Basic test. */

  (void) strcpy(one, "abc");
  (void) memcpy(one, "xyz", 0);
  equal(one, "abc", 4);                 /* Zero-length copy. */

  (void) strcpy(one, "hi there");
  (void) strcpy(two, "foo");
  (void) memcpy(two, one, 9);
  equal(two, "hi there", 5);            /* Just paranoia. */
  equal(one, "hi there", 6);            /* Stomped on source? */

  for (i = 0; i < 16; i++)
    {
      const char *x = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
      strcpy (one, x);
      check (memcpy (one + i, "hi there", 9) == one + i,
             7 + (i * 6));              /* Unaligned destination. */
      check (memcmp (one, x, i) == 0, 8 + (i * 6));  /* Wrote under? */
      equal (one + i, "hi there", 9 + (i * 6));
      check (one[i + 9] == 'x', 10 + (i * 6));       /* Wrote over? */
      check (memcpy (two, one + i, 9) == two,
             11 + (i * 6));             /* Unaligned source. */
      equal (two, "hi there", 12 + (i * 6));
    }
}

static void
test_mempcpy (void)
{
  int i;
  it = "mempcpy";
  check(mempcpy(one, "abc", 4) == one + 4, 1);  /* Returned value. */
  equal(one, "abc", 2);                 /* Did the copy go right? */

  (void) strcpy(one, "abcdefgh");
  (void) mempcpy(one+1, "xyz", 2);
  equal(one, "axydefgh", 3);            /* Basic test. */

  (void) strcpy(one, "abc");
  (void) mempcpy(one, "xyz", 0);
  equal(one, "abc", 4);                 /* Zero-length copy. */

  (void) strcpy(one, "hi there");
  (void) strcpy(two, "foo");
  (void) mempcpy(two, one, 9);
  equal(two, "hi there", 5);            /* Just paranoia. */
  equal(one, "hi there", 6);            /* Stomped on source? */

  for (i = 0; i < 16; i++)
    {
      const char *x = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
      strcpy (one, x);
      check (mempcpy (one + i, "hi there", 9) == one + i + 9,
             7 + (i * 6));              /* Unaligned destination. */
      check (memcmp (one, x, i) == 0, 8 + (i * 6));  /* Wrote under? */
      equal (one + i, "hi there", 9 + (i * 6));
      check (one[i + 9] == 'x', 10 + (i * 6));       /* Wrote over? */
      check (mempcpy (two, one + i, 9) == two + 9,
             11 + (i * 6));             /* Unaligned source. */
      equal (two, "hi there", 12 + (i * 6));
    }
}

static void
test_memmove (void)
{
  it = "memmove";
  check(memmove(one, "abc", 4) == one, 1);      /* Returned value. */
  equal(one, "abc", 2);                 /* Did the copy go right? */

  (void) strcpy(one, "abcdefgh");
  (void) memmove(one+1, "xyz", 2);
  equal(one, "axydefgh", 3);            /* Basic test. */

  (void) strcpy(one, "abc");
  (void) memmove(one, "xyz", 0);
  equal(one, "abc", 4);                 /* Zero-length copy. */

  (void) strcpy(one, "hi there");
  (void) strcpy(two, "foo");
  (void) memmove(two, one, 9);
  equal(two, "hi there", 5);            /* Just paranoia. */
  equal(one, "hi there", 6);            /* Stomped on source? */

  (void) strcpy(one, "abcdefgh");
  (void) memmove(one+1, one, 9);
  equal(one, "aabcdefgh", 7);           /* Overlap, right-to-left. */

  (void) strcpy(one, "abcdefgh");
  (void) memmove(one+1, one+2, 7);
  equal(one, "acdefgh", 8);             /* Overlap, left-to-right. */

  (void) strcpy(one, "abcdefgh");
  (void) memmove(one, one, 9);
  equal(one, "abcdefgh", 9);            /* 100% overlap. */
}

static void
test_memccpy (void)
{
  /* First test like memcpy, then the search part The SVID, the only
     place where memccpy is mentioned, says overlap might fail, so we
     don't try it.  Besides, it's hard to see the rationale for a
     non-left-to-right memccpy.  */
  it = "memccpy";
  check(memccpy(one, "abc", 'q', 4) == NULL, 1);        /* Returned value. */
  equal(one, "abc", 2);                 /* Did the copy go right? */

  (void) strcpy(one, "abcdefgh");
  (void) memccpy(one+1, "xyz", 'q', 2);
  equal(one, "axydefgh", 3);            /* Basic test. */

  (void) strcpy(one, "abc");
  (void) memccpy(one, "xyz", 'q', 0);
  equal(one, "abc", 4);                 /* Zero-length copy. */

  (void) strcpy(one, "hi there");
  (void) strcpy(two, "foo");
  (void) memccpy(two, one, 'q', 9);
  equal(two, "hi there", 5);            /* Just paranoia. */
  equal(one, "hi there", 6);            /* Stomped on source? */

  (void) strcpy(one, "abcdefgh");
  (void) strcpy(two, "horsefeathers");
  check(memccpy(two, one, 'f', 9) == two+6, 7); /* Returned value. */
  equal(one, "abcdefgh", 8);            /* Source intact? */
  equal(two, "abcdefeathers", 9);               /* Copy correct? */

  (void) strcpy(one, "abcd");
  (void) strcpy(two, "bumblebee");
  check(memccpy(two, one, 'a', 4) == two+1, 10);        /* First char. */
  equal(two, "aumblebee", 11);
  check(memccpy(two, one, 'd', 4) == two+4, 12);        /* Last char. */
  equal(two, "abcdlebee", 13);
  (void) strcpy(one, "xyz");
  check(memccpy(two, one, 'x', 1) == two+1, 14);        /* Singleton. */
  equal(two, "xbcdlebee", 15);
}

static void
test_memset (void)
{
  int i;

  it = "memset";
  (void) strcpy(one, "abcdefgh");
  check(memset(one+1, 'x', 3) == one+1, 1);     /* Return value. */
  equal(one, "axxxefgh", 2);            /* Basic test. */

  (void) memset(one+2, 'y', 0);
  equal(one, "axxxefgh", 3);            /* Zero-length set. */

  (void) memset(one+5, 0, 1);
  equal(one, "axxxe", 4);                       /* Zero fill. */
  equal(one+6, "gh", 5);                        /* And the leftover. */

  (void) memset(one+2, 010045, 1);
  equal(one, "ax\045xe", 6);            /* Unsigned char convert. */

  /* Non-8bit fill character.  */
  memset (one, 0x101, sizeof (one));
  for (i = 0; i < (int) sizeof (one); ++i)
    check (one[i] == '\01', 7);

  /* Test for more complex versions of memset, for all alignments and
     lengths up to 256. This test takes a little while, perhaps it should
     be made weaker?  */
  {
    char data[512];
    int j;
    int k;
    int c;

    for (i = 0; i < 512; i++)
      data[i] = 'x';
    for (c = 0; c <= 'y'; c += 'y')  /* check for memset(,0,) and
                                        memset(,'y',) */
      for (j = 0; j < 256; j++)
        for (i = 0; i < 256; i++)
          {
            memset (data + i, c, j);
            for (k = 0; k < i; k++)
              if (data[k] != 'x')
                goto fail;
            for (k = i; k < i+j; k++)
              {
                if (data[k] != c)
                  goto fail;
                data[k] = 'x';
              }
            for (k = i+j; k < 512; k++)
              if (data[k] != 'x')
                goto fail;
            continue;

          fail:
            check (0, 8 + i + j * 256 + (c != 0) * 256 * 256);
          }
  }
}

static void
test_bcopy (void)
{
  /* Much like memcpy.  Berklix manual is silent about overlap, so
     don't test it.  */
  it = "bcopy";
  (void) bcopy("abc", one, 4);
  equal(one, "abc", 1);                 /* Simple copy. */

  (void) strcpy(one, "abcdefgh");
  (void) bcopy("xyz", one+1, 2);
  equal(one, "axydefgh", 2);            /* Basic test. */

  (void) strcpy(one, "abc");
  (void) bcopy("xyz", one, 0);
  equal(one, "abc", 3);                 /* Zero-length copy. */

  (void) strcpy(one, "hi there");
  (void) strcpy(two, "foo");
  (void) bcopy(one, two, 9);
  equal(two, "hi there", 4);            /* Just paranoia. */
  equal(one, "hi there", 5);            /* Stomped on source? */
}

static void
test_bzero (void)
{
  it = "bzero";
  (void) strcpy(one, "abcdef");
  bzero(one+2, 2);
  equal(one, "ab", 1);                  /* Basic test. */
  equal(one+3, "", 2);
  equal(one+4, "ef", 3);

  (void) strcpy(one, "abcdef");
  bzero(one+2, 0);
  equal(one, "abcdef", 4);              /* Zero-length copy. */
}

static void
test_strndup (void)
{
  char *p, *q;
  it = "strndup";
  p = strndup("abcdef", 12);
  check(p != NULL, 1);
  if (p != NULL)
    {
      equal(p, "abcdef", 2);
      q = strndup(p + 1, 2);
      check(q != NULL, 3);
      if (q != NULL)
        equal(q, "bc", 4);
      free (q);
    }
  free (p);
  p = strndup("abc def", 3);
  check(p != NULL, 5);
  if (p != NULL)
    equal(p, "abc", 6);
  free (p);
}

static void
test_bcmp (void)
{
  it = "bcmp";
  check(bcmp("a", "a", 1) == 0, 1);     /* Identity. */
  check(bcmp("abc", "abc", 3) == 0, 2); /* Multicharacter. */
  check(bcmp("abcd", "abce", 4) != 0, 3);       /* Honestly unequal. */
  check(bcmp("abce", "abcd", 4) != 0, 4);
  check(bcmp("alph", "beta", 4) != 0, 5);
  check(bcmp("abce", "abcd", 3) == 0, 6);       /* Count limited. */
  check(bcmp("abc", "def", 0) == 0, 8); /* Zero count. */
}

static void
test_memcmpeq (void)
{
  it = "__memcmpeq";
  check (__memcmpeq ("a", "a", 1) == 0, 1); /* Identity.  */
  check (__memcmpeq ("abc", "abc", 3) == 0, 2); /* Multicharacter.  */
  check (__memcmpeq ("abcd", "abce", 4) != 0, 3); /* Honestly unequal.  */
  check (__memcmpeq ("abce", "abcd", 4) != 0, 4);
  check (__memcmpeq ("alph", "beta", 4) != 0, 5);
  check (__memcmpeq ("abce", "abcd", 3) == 0, 6); /* Count limited.  */
  check (__memcmpeq ("abc", "def", 0) == 0, 8); /* Zero count.  */
}

static void
test_strerror (void)
{
  it = "strerror";
  check(strerror(EDOM) != 0, 1);
  check(strerror(ERANGE) != 0, 2);
  check(strerror(ENOENT) != 0, 3);
}

static void
test_strcasecmp (void)
{
  it = "strcasecmp";
  /* Note that the locale is "C".  */
  check(strcasecmp("a", "a") == 0, 1);
  check(strcasecmp("a", "A") == 0, 2);
  check(strcasecmp("A", "a") == 0, 3);
  check(strcasecmp("a", "b") < 0, 4);
  check(strcasecmp("c", "b") > 0, 5);
  check(strcasecmp("abc", "AbC") == 0, 6);
  check(strcasecmp("0123456789", "0123456789") == 0, 7);
  check(strcasecmp("", "0123456789") < 0, 8);
  check(strcasecmp("AbC", "") > 0, 9);
  check(strcasecmp("AbC", "A") > 0, 10);
  check(strcasecmp("AbC", "Ab") > 0, 11);
  check(strcasecmp("AbC", "ab") > 0, 12);
}

static void
test_strncasecmp (void)
{
  it = "strncasecmp";
  /* Note that the locale is "C".  */
  check(strncasecmp("a", "a", 5) == 0, 1);
  check(strncasecmp("a", "A", 5) == 0, 2);
  check(strncasecmp("A", "a", 5) == 0, 3);
  check(strncasecmp("a", "b", 5) < 0, 4);
  check(strncasecmp("c", "b", 5) > 0, 5);
  check(strncasecmp("abc", "AbC", 5) == 0, 6);
  check(strncasecmp("0123456789", "0123456789", 10) == 0, 7);
  check(strncasecmp("", "0123456789", 10) < 0, 8);
  check(strncasecmp("AbC", "", 5) > 0, 9);
  check(strncasecmp("AbC", "A", 5) > 0, 10);
  check(strncasecmp("AbC", "Ab", 5) > 0, 11);
  check(strncasecmp("AbC", "ab", 5) > 0, 12);
  check(strncasecmp("0123456789", "AbC", 0) == 0, 13);
  check(strncasecmp("AbC", "abc", 1) == 0, 14);
  check(strncasecmp("AbC", "abc", 2) == 0, 15);
  check(strncasecmp("AbC", "abc", 3) == 0, 16);
  check(strncasecmp("AbC", "abcd", 3) == 0, 17);
  check(strncasecmp("AbC", "abcd", 4) < 0, 18);
  check(strncasecmp("ADC", "abcd", 1) == 0, 19);
  check(strncasecmp("ADC", "abcd", 2) > 0, 20);
}

int
main (void)
{
  int status;

  /* Test strcmp first because we use it to test other things.  */
  test_strcmp ();

  /* Test strcpy next because we need it to set up other tests.  */
  test_strcpy ();

  /* A closely related function is stpcpy.  */
  test_stpcpy ();

  /* stpncpy.  */
  test_stpncpy ();

  /* strcat.  */
  test_strcat ();

  /* strncat.  */
  test_strncat ();

  /* strncmp.  */
  test_strncmp ();

  /* strncpy.  */
  test_strncpy ();

  /* strlen.  */
  test_strlen ();

  /* strnlen.  */
  test_strnlen ();

  /* strchr.  */
  test_strchr ();

  /* strchrnul.  */
  test_strchrnul ();

  /* rawmemchr.  */
  test_rawmemchr ();

  /* index - just like strchr.  */
  test_index ();

  /* strrchr.  */
  test_strrchr ();

  /* memrchr.  */
  test_memrchr ();

  /* rindex - just like strrchr.  */
  test_rindex ();

  /* strpbrk - somewhat like strchr.  */
  test_strpbrk ();

  /* strstr - somewhat like strchr.  */
  test_strstr ();

  /* strspn.  */
  test_strspn ();

  /* strcspn.  */
  test_strcspn ();

  /* strtok - the hard one.  */
  test_strtok ();

  /* strtok_r.  */
  test_strtok_r ();

  /* strsep.  */
  test_strsep ();

  /* memcmp.  */
  test_memcmp ();

  /* memchr.  */
  test_memchr ();

  /* memcpy - need not work for overlap.  */
  test_memcpy ();

  /* memmove - must work on overlap.  */
  test_memmove ();

  /* mempcpy */
  test_mempcpy ();

  /* memccpy.  */
  test_memccpy ();

  /* memset.  */
  test_memset ();

  /* bcopy.  */
  test_bcopy ();

  /* bzero.  */
  test_bzero ();

  /* bcmp - somewhat like memcmp.  */
  test_bcmp ();

  /* __memcmpeq - somewhat like memcmp.  */
  test_memcmpeq ();

  /* strndup.  */
  test_strndup ();

  /* strerror - VERY system-dependent.  */
  test_strerror ();

  /* strcasecmp.  Without locale dependencies.  */
  test_strcasecmp ();

  /* strncasecmp.  Without locale dependencies.  */
  test_strncasecmp ();

  if (errors == 0)
    {
      status = EXIT_SUCCESS;
      puts("No errors.");
    }
  else
    {
      status = EXIT_FAILURE;
      printf("%zd errors.\n", errors);
    }

  return status;
}