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  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   9  * COPYRIGHT file in the root directory of the nmh distribution for
  10  * complete copyright information.
  11  */
  12
  13 #include <h/mh.h>
  14
  15 /* allocate this number of pointers at a time */
  16 #define NUMBROKEN 256
  17
  18 static char **broken = NULL;    /* array of substring start addresses */
  19 static int len = 0;             /* current size of "broken"           */
  20
  21 /*
  22  * static prototypes
  23  */
  24 static int brkany (char, char *);
  25
  26
  27 char **
  28 brkstring (char *str, char *brksep, char *brkterm)
  29 {
  30     int i;
  31     char c, *s;
  32
  33     /* allocate initial space for pointers on first call */
  34     if (!broken) {
  35         len = NUMBROKEN;
  36         if (!(broken = (char **) malloc ((size_t) (len * sizeof(*broken)))))
  37             adios (NULL, "unable to malloc array in brkstring");
  38     }
  39
  40     /*
  41      * scan string, replacing separators with zeroes
  42      * and enter start addresses in "broken".
  43      */
  44     s = str;
  45
  46     for (i = 0;; i++) {
  47
  48         /* enlarge pointer array, if necessary */
  49         if (i >= len) {
  50             len += NUMBROKEN;
  51             if (!(broken = realloc (broken, (size_t) (len * sizeof(*broken)))))
  52                 adios (NULL, "unable to realloc array in brkstring");
  53         }
  54
  55         while (brkany (c = *s, brksep))
  56             *s++ = '\0';
  57
  58         /*
  59          * we are either at the end of the string, or the
  60          * terminator found has been found, so finish up.
  61          */
  62         if (!c || brkany (c, brkterm)) {
  63             *s = '\0';
  64             broken[i] = NULL;
  65             return broken;
  66         }
  67
  68         /* set next start addr */
  69         broken[i] = s;
  70
  71         while ((c = *++s) && !brkany (c, brksep) && !brkany (c, brkterm))
  72             ;   /* empty body */
  73     }
  74
  75     return broken;      /* NOT REACHED */
  76 }
  77
  78
  79 /*
  80  * If the character is in the string,
  81  * return 1, else return 0.
  82  */
  83
  84 static int
  85 brkany (char c, char *str)
  86 {
  87     char *s;
  88
  89     if (str) {
  90         for (s = str; *s; s++)
  91             if (c == *s)
  92                 return 1;
  93     }
  94     return 0;
  95 }