1  /* Test the strlcat function.
       2     Copyright (C) 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  #include <string.h>
      20  #include <stdlib.h>
      21  #include <stdio.h>
      22  #include <support/check.h>
      23  
      24  static int
      25  do_test (void)
      26  {
      27    struct {
      28      char buf1[16];
      29      char buf2[16];
      30    } s;
      31  
      32    /* Nothing is written to the destination if its size is 0.  */
      33    memset (&s, '@', sizeof (s));
      34    TEST_COMPARE (strlcat (s.buf1, "", 0), 0);
      35    TEST_COMPARE_BLOB (&s, sizeof (s), "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
      36    TEST_COMPARE (strlcat (s.buf1, "Hello!", 0), 6);
      37    TEST_COMPARE_BLOB (&s, sizeof (s), "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
      38  
      39    /* No bytes are are modified in the target buffer if the source
      40       string is short enough.  */
      41    memset (&s, '@', sizeof (s));
      42    strcpy (s.buf1, "He");
      43    TEST_COMPARE (strlcat (s.buf1, "llo!", sizeof (s.buf1)), 6);
      44    TEST_COMPARE_BLOB (&s, sizeof (s), "Hello!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
      45  
      46    /* A source string which fits exactly into the destination buffer is
      47       not truncated.  */
      48    memset (&s, '@', sizeof (s));
      49    strcpy (s.buf1, "H");
      50    TEST_COMPARE (strlcat (s.buf1, "ello, world!!!", sizeof (s.buf1)), 15);
      51    TEST_COMPARE_BLOB (&s, sizeof (s),
      52  		     "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
      53  
      54    /* A source string one character longer than the destination buffer
      55       is truncated by one character.  The total length is returned.  */
      56    memset (&s, '@', sizeof (s));
      57    strcpy (s.buf1, "Hello");
      58    TEST_COMPARE (strlcat (s.buf1, ", world!!!!", sizeof (s.buf1)), 16);
      59    TEST_COMPARE_BLOB (&s, sizeof (s),
      60  		     "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
      61  
      62    /* An even longer source string is truncated as well, and the total
      63       length is returned.  */
      64    memset (&s, '@', sizeof (s));
      65    strcpy (s.buf1, "Hello,");
      66    TEST_COMPARE (strlcat (s.buf1, " world!!!!!!!!", sizeof (s.buf1)), 20);
      67    TEST_COMPARE_BLOB (&s, sizeof (s),
      68  		     "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
      69  
      70    /* A destination string which is not NUL-terminated does not result
      71       in any changes to the buffer.  */
      72    memset (&s, '@', sizeof (s));
      73    memset (s.buf1, '$', sizeof (s.buf1));
      74    TEST_COMPARE (strlcat (s.buf1, "", sizeof (s.buf1)), 16);
      75    TEST_COMPARE_BLOB (&s, sizeof (s), "$$$$$$$$$$$$$$$$@@@@@@@@@@@@@@@@", 32);
      76    TEST_COMPARE (strlcat (s.buf1, "Hello!", sizeof (s.buf1)), 22);
      77    TEST_COMPARE_BLOB (&s, sizeof (s), "$$$$$$$$$$$$$$$$@@@@@@@@@@@@@@@@", 32);
      78    TEST_COMPARE (strlcat (s.buf1, "Hello, world!!!!!!!!", sizeof (s.buf1)), 36);
      79    TEST_COMPARE_BLOB (&s, sizeof (s), "$$$$$$$$$$$$$$$$@@@@@@@@@@@@@@@@", 32);
      80  
      81    return 0;
      82  }
      83  
      84  #include <support/test-driver.c>