Remove strdup implementation (#447)

Every platform we support has strdup, so this can be removed.

hdf/src/hdfalloc.c

@@ -118,40 +118,3 @@ HIstrncpy(char *dest, const char *source, intn len)
     *dest = '\0'; /* Force the last byte be '\0'   */
     return (destp);
 } /* end HIstrncpy() */
-/* *INDENT-OFF* */
-/* GNU indent 1.9.1 urps on this section, so turn off indenting for now -QAK */
-
-/*--------------------------------------------------------------------------
- NAME
-    strdup -- in-library replacement for non-ANSI strdup()
- USAGE
-    char *strdup(s)
-        const char *s;          IN: pointer to the string to duplicate
- RETURNS
-    Pointer to the duplicated string, or NULL on failure.
- DESCRIPTION
-    Duplicates a string (i.e. allocates space and copies it over).
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
-    Acts like strdup().
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
-char *
-strdup(const char *s)
-{
-    char *ret;
-
-    /* Make sure original string is not NULL */
-    if (s == NULL)
-        return (NULL);
-
-    /* Allocate space */
-    ret = (char *)malloc((uint32)strlen(s) + 1);
-    if (ret == NULL)
-        return (NULL);
-
-    /* Copy the original string and return it */
-    strcpy(ret, s);
-    return (ret);
-} /* end strdup() */

hdf/src/hproto.h

@@ -324,8 +324,6 @@ HDFLIBAPI char *HIstrncpy(char *dest, const char *source, intn len);
 
 HDFLIBAPI int32 HDspaceleft(void);
 
-HDFPUBLIC char *strdup(const char *s);
-
 HDFLIBAPI intn HDc2fstr(char *str, intn len);
 
 HDFLIBAPI char *HDf2cstring(_fcd fdesc, intn len);