/* write the checkpoint data to fd, and return whether the write was successful */
int write_checkpoint(int fd, int rank, int ckpt, char* buf, size_t size)
{
int rc;
int valid = 0;
char rank_buf[7];
char ckpt_buf[7];
size_t field_size = 6;
/* write the rank id */
sprintf(rank_buf, "%06d", rank);
rc = reliable_write(fd, rank_buf, field_size);
if (rc < 0) {
valid = 0;
}
/* write the checkpoint id (application timestep) */
sprintf(ckpt_buf, "%06d", ckpt);
rc = reliable_write(fd, ckpt_buf, field_size);
if (rc < 0) {
valid = 0;
}
/* write the checkpoint data */
rc = reliable_write(fd, buf, size);
if (rc < 0) {
valid = 0;
}
return valid;
}
/**
* pkt_send - send packet and destroy
* @fd: file descriptor to write it to
* @pkt: packet structure
*
* Writes the packet length into the actual transmission buffer, sends the
* packet out to @fd and then destroys it.
*/
void pkt_send(int fd, struct lo_packet *pkt)
{
struct ccgfs_pkt_header *hdr = pkt->data;
hdr->length = cpu_to_le32(pkt->length);
reliable_write(fd, hdr, pkt->length);
__pkt_destroy(pkt);
}
int demultiplex_write(void *session, int fd, int id, const void *buf, size_t size)
{
int result;
msg_header_t msg_header;
int write_lock_held = 0;
int error_return = -1;
msg_header.msg_size = size;
msg_header.msg_target = id;
result = take_write_lock(session);
if (result == -1)
goto error;
write_lock_held = 1;
result = reliable_write(fd, &msg_header, sizeof(msg_header));
if (result == -1) {
set_last_error("Error writing header from client to server");
goto error;
}
if (result == 0)
goto eof_error;
result = reliable_write(fd, buf, size);
if (result == -1) {
set_last_error("Error writing message from client to server");
goto error;
}
if (result == 0)
goto eof_error;
result = release_write_lock(session);
if (result == -1)
goto error;
write_lock_held = 0;
return size;
eof_error:
error_return = 0;
error:
if (write_lock_held)
release_write_lock(session);
return error_return;
}
/**
* Writes the given number of bytes from the output_buffer to the file descriptor.
* This is just a wrapper around write(2), because write(2) can write less than
* the given number of bytes.
*
* @param fd File descriptor.
* @param output_buffer Buffer with data to be written. Must be at least size bytes long.
* @param size Number of bytes to write.
* @throws std::system_error On error.
*/
inline void reliable_write(const int fd, const char* output_buffer, const size_t size) {
reliable_write(fd, reinterpret_cast<const unsigned char*>(output_buffer), size);
}
