libbb/trim.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Utility routines.
   4  *
   5  * Copyright (C) many different people.
   6  * If you wrote this, please acknowledge your work.
   7  *
   8  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   9  */
  10 #include "libbb.h"
  11
  12 char* FAST_FUNC trim(char *s)
  13 {
  14         size_t len = strlen(s);
  15         size_t old = len;
  16
  17         /* trim trailing whitespace */
  18         while (len && isspace(s[len-1]))
  19                 --len;
  20
  21         /* trim leading whitespace */
  22         if (len) {
  23                 char *nws = skip_whitespace(s);
  24                 if ((nws - s) != 0) {
  25                         len -= (nws - s);
  26                         memmove(s, nws, len);
  27                 }
  28         }
  29
  30         s += len;
  31         /* If it was a "const char*" which does not need trimming,
  32          * avoid superfluous store */
  33         if (old != len)
  34                 *s = '\0';
  35
  36         return s;
  37 }