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