diplodocus.org Git - nmh/blob - sbr/add.c

   1
   2 /*
   3  * add.c -- If "s1" is NULL, this routine just creates a
   4  *       -- copy of "s2" into newly malloc'ed memory.
   5  *       --
   6  *       -- If "s1" is not NULL, then copy the concatenation
   7  *       -- of "s1" and "s2" (note the order) into newly
   8  *       -- malloc'ed memory.  Then free "s1".
   9  *
  10  * $Id$
  11  */
  12
  13 #include <h/mh.h>
  14
  15 char *
  16 add (char *s2, char *s1)
  17 {
  18     char *cp;
  19     size_t len1 = 0, len2 = 0;
  20
  21     if (s1)
  22         len1 = strlen (s1);
  23     if (s2)
  24         len2 = strlen (s2);
  25
  26
  27     if (!(cp = malloc (len1 + len2 + 1)))
  28         adios (NULL, "unable to allocate string storage");
  29
  30     /* Copy s1 and free it */
  31     if (s1) {
  32         memcpy (cp, s1, len1);
  33         free (s1);
  34     }
  35
  36     /* Copy s2 */
  37     if (s2)
  38         memcpy (cp + len1, s2, len2);
  39
  40     /* Now NULL terminate the string */
  41     cp[len1 + len2] = '\0';
  42
  43     return cp;
  44 }