shithub: orca

ref: a52a95b4c703124ac5a876904d69233aa26f5726
dir: /osc_out.c/

#include "osc_out.h"

//#include <sys/socket.h>
#include <arpa/inet.h>
#include <errno.h>
#include <netinet/in.h>

struct Oosc_dev {
  int fd;
  struct sockaddr_in addr;
};

Oosc_udp_create_error oosc_dev_create_udp(Oosc_dev** out_ptr, U16 port) {
  int udpfd = socket(AF_INET, SOCK_DGRAM, 0);
  if (udpfd < 0) {
    fprintf(stderr, "Failed to open UDP socket, error number: %d\n", errno);
    return Oosc_udp_create_error_couldnt_open_socket;
  }
  struct sockaddr_in addr;
  memset(&addr, 0, sizeof(addr));
  addr.sin_family = AF_INET;
  addr.sin_addr.s_addr = inet_addr("127.0.0.1");
  addr.sin_port = htons((U16)port);
  Oosc_dev* dev = malloc(sizeof(Oosc_dev));
  dev->fd = udpfd;
  dev->addr = addr;
  *out_ptr = dev;
  return Oosc_udp_create_error_ok;
}

void oosc_dev_destroy(Oosc_dev* dev) {
  close(dev->fd);
  free(dev);
}

void oosc_send_datagram(Oosc_dev* dev, char const* data, Usz size) {
  ssize_t res = sendto(dev->fd, data, size, 0, (struct sockaddr*)&dev->addr,
                       sizeof(dev->addr));
  if (res < 0) {
    fprintf(stderr, "UDP message send failed\n");
    exit(1);
  }
}

static bool oosc_write_strn(char* restrict buffer, Usz buffer_size,
                            Usz* buffer_pos, char const* restrict in_str,
                            Usz in_str_len) {
  // no overflow check, should be fine
  Usz in_plus_null = in_str_len + 1;
  Usz null_pad = (4 - in_plus_null % 4) % 4;
  Usz needed = in_plus_null + null_pad;
  Usz cur_pos = *buffer_pos;
  if (cur_pos + needed >= buffer_size)
    return false;
  for (Usz i = 0; i < in_str_len; ++i) {
    buffer[cur_pos + i] = in_str[i];
  }
  buffer[cur_pos + in_str_len] = 0;
  cur_pos += in_plus_null;
  for (Usz i = 0; i < null_pad; ++i) {
    buffer[cur_pos + i] = 0;
  }
  *buffer_pos = cur_pos + null_pad;
  return true;
}

void oosc_send_int32s(Oosc_dev* dev, char const* osc_address, I32 const* vals,
                      Usz count) {
  char buffer[2048];
  Usz buf_pos = 0;
  if (!oosc_write_strn(buffer, sizeof(buffer), &buf_pos, osc_address,
                       strlen(osc_address)))
    return;
  Usz typetag_str_size = 1 + count + 1; // comma, 'i'... , null
  Usz typetag_str_null_pad = (4 - typetag_str_size % 4) % 4;
  if (buf_pos + typetag_str_size + typetag_str_null_pad > sizeof(buffer))
    return;
  buffer[buf_pos] = ',';
  ++buf_pos;
  for (Usz i = 0; i < count; ++i) {
    buffer[buf_pos + i] = 'i';
  }
  buffer[buf_pos + count] = 0;
  buf_pos += count + 1;
  for (Usz i = 0; i < typetag_str_null_pad; ++i) {
    buffer[buf_pos + i] = 0;
  }
  buf_pos += typetag_str_null_pad;
  Usz ints_size = count * sizeof(I32);
  if (buf_pos + ints_size > sizeof(buffer))
    return;
  for (Usz i = 0; i < count; ++i) {
    union {
      I32 i;
      U32 u;
    } pun;
    pun.i = vals[i];
    U32 u_ne = htonl(pun.u);
    memcpy(buffer + buf_pos, &u_ne, sizeof(u_ne));
    buf_pos += sizeof(u_ne);
  }
  oosc_send_datagram(dev, buffer, buf_pos);
}