src/ipc.c


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#ifndef IPC_C
#define IPC_C

#include <mqueue.h>
#include <stdio.h>
#include <stdlib.h>

struct mq_attr attr = {
    .mq_flags = 0,
    .mq_maxmsg = 10,
    .mq_msgsize = 1024,
    .mq_curmsgs = 0,
};

char* read_queue(mqd_t target) {
  char* buf = malloc(attr.mq_msgsize);
  int n = mq_receive(target, buf, attr.mq_msgsize, NULL);
  if (n == -1) {
    perror("mq_receive");
    free(buf);
    return NULL;
  }
  return buf;
}

void send_queue(mqd_t target, const char* msg, int n) {
  mq_send(target, msg, n, 0);
}

int get_num_messages(mqd_t target) {
  struct mq_attr target_attr;

  if (mq_getattr(target, &target_attr) == -1) {
      perror("mq_getattr");
      exit(1);
  }

  return target_attr.mq_curmsgs;
}

#endif // IPC_C