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

   1
   2 /*
   3  * brkstring.c -- (destructively) split a string into
   4  *             -- an array of substrings
   5  *
   6  * $Id$
   7  */
   8
   9 #include <h/mh.h>
  10
  11 /* allocate this number of pointers at a time */
  12 #define NUMBROKEN 256
  13
  14 static char **broken = NULL;    /* array of substring start addresses */
  15 static int len = 0;             /* current size of "broken"           */
  16
  17 /*
  18  * static prototypes
  19  */
  20 static int brkany (char, char *);
  21
  22
  23 char **
  24 brkstring (char *str, char *brksep, char *brkterm)
  25 {
  26     int i;
  27     char c, *s;
  28
  29     /* allocate initial space for pointers on first call */
  30     if (!broken) {
  31         len = NUMBROKEN;
  32         if (!(broken = (char **) malloc ((size_t) (len * sizeof(*broken)))))
  33             adios (NULL, "unable to malloc array in brkstring");
  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             if (!(broken = realloc (broken, (size_t) (len * sizeof(*broken)))))
  48                 adios (NULL, "unable to realloc array in brkstring");
  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             return broken;
  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;      /* NOT REACHED */
  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     char *s;
  84
  85     if (str) {
  86         for (s = str; *s; s++)
  87             if (c == *s)
  88                 return 1;
  89     }
  90     return 0;
  91 }