examples/count.c

   1 /*
   2  * Copyright (C) 2011 Felix Fietkau <nbd@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <stdio.h>
  15 #include <stdint.h>
  16 #include <stdlib.h>
  17 #include "count.h"
  18
  19 char *count_to_number(uint32_t num)
  20 {
  21         uint32_t ptr = 0, size = 0;
  22         uint32_t written = 0, i;
  23         int new_line_every_n_numbers = 30;
  24         char *s;
  25
  26         for (i=0; i < num; ++i) {
  27                 size += snprintf(NULL, 0, "%u ", i);
  28                 if (i > 0 && i % new_line_every_n_numbers == 0)
  29                         size++;
  30         }
  31         size++; /* one for null char */
  32
  33         s = calloc(size, sizeof(char));
  34         if (!s)
  35                 goto out;
  36
  37         for (i=0; i < num; ++i) {
  38                 written = sprintf(&s[ptr], "%u ", i);
  39                 ptr  += written;
  40                 if (i > 0 && i % new_line_every_n_numbers == 0) {
  41                         sprintf(&s[ptr], "\n");
  42                         ptr++;
  43                 }
  44         }
  45
  46 out:
  47         return s;
  48 }