Munin contributed plugins

#include <string.h>

#include <stdio.h>

#include "common.h"

#define ENTROPY_AVAIL "/proc/sys/kernel/random/entropy_avail"

int entropy(int argc, char **argv) {

        FILE *f;

        int entropy;

        if(argc > 1) {

                if(!strcmp(argv[1], "config")) {

                        puts("graph_title Available entropy\n"

                                "graph_args --base 1000 -l 0\n"

                                "graph_vlabel entropy (bytes)\n"

                                "graph_scale no\n"

                                "graph_category system\n"

                                "graph_info This graph shows the amount of entropy available in the system.\n"

                                "entropy.label entropy\n"

                                "entropy.info The number of random bytes available. This is typically used by cryptographic applications.");

                        print_warncrit("entropy");

                        return 0;

                }

                if(!strcmp(argv[1], "autoconf"))

                        return writeyes();

        }

        if(!(f=fopen(ENTROPY_AVAIL, "r"))) {

                fputs("cannot open " ENTROPY_AVAIL "\n", stderr);

                return 1;

        }

        if(1 != fscanf(f, "%d", &entropy)) {

                fputs("cannot read from " ENTROPY_AVAIL "\n", stderr);

                fclose(f);

                return 1;

        }

        fclose(f);

        printf("entropy.value %d\n", entropy);

        return 0;

}