udpx

gistfile1.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <stdint.h>
#include "udpx.pb-c.h"

#define debug(M, ...) fprintf(stderr, "%i: DEBUG %10.10s:%3.0d: " M "\n", getpid(), __FILE__, __LINE__, ##__VA_ARGS__); fflush(stderr);

#define log_err(M, ...) fprintf(stderr, "%i: ERROR errno:%i %10.10s:%3.0d: " M "\n", getpid(), errno, __FILE__, __LINE__, ##__VA_ARGS__); fflush(stderr);

#define quit_if(COND, ...) do { \
        if(COND) { \
                log_err(__VA_ARGS__); \
                if (errno != 0) perror(NULL); \
                exit(errno); \
        } \
} while(0);

#define MAX_ATTEMPTS 100000
#define MAX_SIZE 1500
#define RAND_DEV "/dev/urandom"
char *hex = "0123456789ABCDEF";
uint8_t *buf_to_hex(uint8_t *buf, int len) {
        static uint8_t out[MAX_SIZE * 2 + 1];
        quit_if(len > MAX_SIZE, "len too long");
        int i;
        for (i = 0; i < len; i++) {
                out[2*i] = hex[buf[i] >> 4]; // top nibble
                out[2*i + 1] = hex[buf[i] & 15];
        }
        out[2*i] = '\0';
        return out;
}

int main (int argc, const char * argv[]) {
        int fd = open(RAND_DEV, O_RDONLY);
        quit_if(fd < 0, "couldn't open %s", RAND_DEV);
        srand(time(NULL));
        for (int i = 0; i < MAX_ATTEMPTS; i++) {
                int len = rand() % MAX_SIZE;
                uint8_t buf[len + 1];
                int r = read(fd, buf, len);
                quit_if(r != len, "bad read, expected %i bytes, read %i", r, len);
                //debug("read %i bytes from %s", r, RAND_DEV);
                Com__Thorcom__Udpx__Udpx *udpx = com__thorcom__udpx__udpx__unpack(NULL, len, buf);
                if (udpx == NULL) {
                        //debug("error unpacking random message");
                } else {
                        //debug("managed to unpack random message: %s", buf_to_hex(buf, len));
                        quit_if(1, "it happened");
                }
        }
}