strsep bug

[Bruno Haible]

Hi Yoann,

The strsep replacement has a bug: when passed an empty set of delimiters,
according to the Linux and BSD manual page the token should be set to
the entire string, and *stringp should be set to NULL (so indicating there
are no more tokens). The implementation in gnulib sets *stringp to the end
of the string, so that strsep will repeatedly, infinitely, yield empty
tokens.

Here is a fix, together with an optimization of the length 1 case.

OK to apply?

2007-02-05  Bruno Haible  <[EMAIL PROTECTED]>

        * lib/strsep.c (strsep): Fix actions in case of no delimiters.
        Optimize search in case of 1 delimiter.

*** lib/strsep.c        26 Jan 2007 22:16:55 -0000      1.5
--- lib/strsep.c        6 Feb 2007 00:40:38 -0000
***************
*** 29,47 ****
    char *start = *stringp;
    char *ptr;
  
!   if (!start)
      return NULL;
  
!   if (!*delim)
!     ptr = start + strlen (start);
    else
      {
!       ptr = strpbrk (start, delim);
!       if (!ptr)
!       {
!         *stringp = NULL;
!         return start;
!       }
      }
  
    *ptr = '\0';
--- 29,54 ----
    char *start = *stringp;
    char *ptr;
  
!   if (start == NULL)
      return NULL;
  
!   /* Optimize the case of no delimiters.  */
!   if (delim[0] == '\0')
!     {
!       *stringp = NULL;
!       return start;
!     }
! 
!   /* Optimize the case of one delimiter.  */
!   if (delim[1] == '\0')
!     ptr = strchr (start, delim[0]);
    else
+     /* The general case.  */
+     ptr = strpbrk (start, delim);
+   if (ptr == NULL)
      {
!       *stringp = NULL;
!       return start;
      }
  
    *ptr = '\0';