proplib/prop_du.c

   1 #include <err.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <sys/wait.h>    /* for waitpid() macros */
   6 #include <prop/proplib.h>
   7
   8 #define INIT_CAPACITY 100
   9 #define MAX_STR 100
  10 #define MAX_TOKENS 3
  11
  12 int main(void)
  13 {
  14     char str[MAX_STR];
  15     char *tokens[MAX_TOKENS];    /* for ``du'' output parse */
  16     char *last, *p;
  17     int i, ret;
  18     FILE *fp;
  19     prop_dictionary_t pd;
  20     prop_number_t pn;
  21
  22     /* Initiate pipe stream to ``du'' */
  23     fp = popen("du", "r");
  24     if (fp == NULL) {
  25         perror("popen()");
  26         exit(EXIT_FAILURE);
  27     }
  28
  29     /* Create dictionary */
  30     pd = prop_dictionary_create_with_capacity(INIT_CAPACITY);
  31     if (pd == NULL) {
  32         pclose(fp);
  33         errx(EXIT_FAILURE, "prop_dictionary_create_with_capacity()");
  34     }
  35
  36     /* Read from stream */
  37     while (fgets(str, MAX_STR, fp) != NULL) {
  38         /* Parse output of ``du'' command */
  39         i = 0;
  40         p = strtok_r(str, "\t", &last);
  41         while (p && i < MAX_TOKENS - 1) {
  42             tokens[i++] = p;
  43             p = strtok_r(NULL, "\t", &last);
  44         }
  45         tokens[i] = NULL;
  46
  47         /* Trim '\n' from tokens[1] */
  48         (tokens[1])[strlen(tokens[1]) - 1] = '\0';
  49
  50         /*
  51          * We use a signed prop_number_t object, so that
  52          * when externalized it will be represented as decimal
  53          * (unsigned numbers are externalized in base-16).
  54          *
  55          * Note: atoi() does not detect errors, but we trust
  56          * ``du'' to provide us with valid input. Otherwise,
  57          * we should use strtol(3) or sscanf(3).
  58          */
  59         pn = prop_number_create_integer(atoi(tokens[0]));
  60
  61         /* Add a <path, size> pair in our dictionary */
  62         if (prop_dictionary_set(pd, tokens[1], pn) == FALSE) {
  63             prop_object_release(pn);
  64             prop_object_release(pd);
  65             errx(EXIT_FAILURE, "prop_dictionary_set()");
  66         }
  67
  68         /* Release prop_number_t object */
  69         prop_object_release(pn);
  70     }
  71
  72     /* Externalize dictionary to file in XML representation */
  73     if (prop_dictionary_externalize_to_file(pd, "./data.xml") == FALSE) {
  74         prop_object_release(pd);
  75         errx(EXIT_FAILURE, "prop_dictionary_externalize_to_file()");
  76     }
  77
  78     /* Release dictionary */
  79     prop_object_release(pd);
  80
  81     /* Close pipe stream */
  82     ret = pclose(fp);
  83     if  (ret == -1) {
  84         perror("pclose()");
  85         exit(EXIT_FAILURE);
  86     }
  87
  88     return EXIT_SUCCESS;
  89 }