dada_hell.c

#include <dada_def.h>
#include <dada_hdu.h>
#include <fcntl.h>
#include <ipcbuf.h>
#include <multilog.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>

void print_arr(char *ptr, int len) {
  printf("[");
  for (int i = 0; i < len; i++) {
    printf(" %08x,", ptr[i]);
  }
  printf(" ]\n");
}

int write_hdu(ipcbuf_t *buf, int eod) {
  if (ipcbuf_lock_write(buf) < 0) {
    printf("Could not lock HDU for writing\n");
    return -1;
  }
  // Get the next ptr to write to
  char *ptr = ipcbuf_get_next_write(buf);
  // Bail if its NULL
  if (ptr == NULL) {
    printf("Write ptr is null\n");
    return -1;
  }
  // Generate some nonsense
  int bufsz = ipcbuf_get_bufsz(buf);
  char bytes[bufsz];
  int fd = open("/dev/random", O_RDONLY);
  read(fd, bytes, bufsz);
  // Write some nonsense
  memcpy(ptr, bytes, bufsz);
  // Print our nonsense
  printf("Writing to ringbuffer:   ");
  print_arr(ptr, bufsz);
  // Set EOD
  if (eod)
    ipcbuf_enable_eod(buf);
  // Mark as filled
  if (ipcbuf_mark_filled(buf, bufsz) < 0) {
    printf("Could not mark buf as filled\n");
    return -1;
  }
  // Unlock
  if (ipcbuf_unlock_write(buf) < 0) {
    printf("Could not lock HDU for writing\n");
    return -1;
  }
}

int read_hdu(ipcbuf_t *buf) {
  // Lock
  if (ipcbuf_lock_read(buf) < 0) {
    printf("Could not lock HDU for writing\n");
    return -1;
  }
  uint64_t readsz;
  char *ptr = ipcbuf_get_next_read(buf, &readsz);
  if (ptr == NULL) {
    printf("Read ptr is null\n");
    return -1;
  }
  // Read
  char bytes[readsz];
  memcpy(bytes, ptr, readsz);
  printf("Reading from ringbuffer: ");
  print_arr(bytes, readsz);
  // Mark as filled
  if (ipcbuf_mark_cleared(buf) < 0) {
    printf("Could not mark buf as cleared\n");
    return -1;
  }
  // Check for EOD
  printf("EOD? - %d\n", ipcbuf_eod(buf));
  // Unlock
  if (ipcbuf_unlock_read(buf) < 0) {
    printf("Could not lock HDU for writing\n");
    return -1;
  }
}

int main() {
  int dada_key = 0xbfff;

  ipcbuf_t data_block = IPCBUF_INIT;
  ipcbuf_t header = IPCBUF_INIT;

  // create data ring buffer - 4 blocks of 8 bytes
  if (ipcbuf_create_work(&data_block, dada_key, 4, 8, 1, -1) < 0) {
    printf("Could not create DADA data block\n");
    return -1;
  }

  // create header ring buffer - 4 blocks of 8 bytes (we're not going to use it)
  if (ipcbuf_create(&header, dada_key + 1, 4, 8, 1) < 0) {
    printf("Could not create DADA header block\n");
    return -1;
  }

  // Write a few
  write_hdu(&data_block,0);
  write_hdu(&data_block,0);
  write_hdu(&data_block,1);
  write_hdu(&data_block,0);

  // Read a few
  read_hdu(&data_block);
  read_hdu(&data_block);
  read_hdu(&data_block);
  read_hdu(&data_block);

  // Teardown
  ipcbuf_destroy(&data_block);
  ipcbuf_destroy(&header);

  return 0;
}