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

   1 /* brkstring.c -- (destructively) split a string into
   2  *             -- an array of substrings
   3  *
   4  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   5  * COPYRIGHT file in the root directory of the nmh distribution for
   6  * complete copyright information.
   7  */
   8
   9 #include "h/mh.h"
  10 #include "brkstring.h"
  11 #include "h/utils.h"
  12
  13 /* allocate this number of pointers at a time */
  14 #define NUMBROKEN 256
  15
  16 static char **broken = NULL;    /* array of substring start addresses */
  17 static int len = 0;             /* current size of "broken"           */
  18
  19 /*
  20  * static prototypes
  21  */
  22 static int brkany (char, char *);
  23
  24
  25 char **
  26 brkstring (char *str, char *brksep, char *brkterm)
  27 {
  28     int i;
  29     char c, *s;
  30
  31     /* allocate initial space for pointers on first call */
  32     if (!broken) {
  33         len = NUMBROKEN;
  34         broken = mh_xmalloc ((size_t) (len * sizeof(*broken)));
  35     }
  36
  37     /*
  38      * scan string, replacing separators with zeroes
  39      * and enter start addresses in "broken".
  40      */
  41     s = str;
  42
  43     for (i = 0;; i++) {
  44
  45         /* enlarge pointer array, if necessary */
  46         if (i >= len) {
  47             len += NUMBROKEN;
  48             broken = mh_xrealloc (broken, (size_t) (len * sizeof(*broken)));
  49         }
  50
  51         while (brkany (c = *s, brksep))
  52             *s++ = '\0';
  53
  54         /*
  55          * we are either at the end of the string, or the
  56          * terminator found has been found, so finish up.
  57          */
  58         if (!c || brkany (c, brkterm)) {
  59             *s = '\0';
  60             broken[i] = NULL;
  61             break;
  62         }
  63
  64         /* set next start addr */
  65         broken[i] = s;
  66
  67         while ((c = *++s) && !brkany (c, brksep) && !brkany (c, brkterm))
  68             ;   /* empty body */
  69     }
  70
  71     return broken;
  72 }
  73
  74
  75 /*
  76  * If the character is in the string,
  77  * return 1, else return 0.
  78  */
  79
  80 static int
  81 brkany (char c, char *str)
  82 {
  83     return str && c && strchr(str, c);
  84 }