KEK/dc11.cpp
folkert van heusden a982a3c9d9
basic setup
2024-04-30 09:06:26 +02:00

169 lines
3.3 KiB
C++

// (C) 2024 by Folkert van Heusden
// Released under MIT license
#include <cstring>
#include <poll.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include "bus.h"
#include "cpu.h"
#include "dc11.h"
#include "log.h"
dc11::dc11(const int base_port, bus *const b):
base_port(base_port),
b(b)
{
th = new std::thread(std::ref(*this));
}
dc11::~dc11()
{
stop_flag = true;
if (th) {
th->join();
delete th;
}
}
void dc11::operator()()
{
int fds[dc11_n_lines] = { };
pollfd pfds[8] = { };
for(int i=0; i<dc11_n_lines; i++) {
// listen on port
pfds[i].fd = socket(AF_INET, SOCK_STREAM, 0);
int port = base_port + i + 1;
sockaddr_in listen_addr;
memset(&listen_addr, 0, sizeof(listen_addr));
listen_addr.sin_family = AF_INET;
listen_addr.sin_addr.s_addr = htonl(INADDR_ANY);
listen_addr.sin_port = htons(port);
if (bind(pfds[i].fd, reinterpret_cast<struct sockaddr *>(&listen_addr), sizeof(listen_addr)) == -1) {
close(pfds[i].fd);
fds[i] = -1;
DOLOG(warning, true, "Cannot bind to port %d (DC11)", port);
}
pfds[i].events = POLLIN;
// client session
pfds[dc11_n_lines + i].fd = socket(AF_INET, SOCK_STREAM, 0);
pfds[dc11_n_lines + i].events = POLLIN;
}
while(!stop_flag) {
int rc = poll(pfds, dc11_n_lines * 2, 100);
if (rc == 0)
continue;
// accept any new session
for(int i=0; i<dc11_n_lines; i++) {
if (pfds[i].revents != POLLIN)
continue;
int client_i = dc11_n_lines + i;
// disconnect any existing client session
// yes, one can ddos with this
if (pfds[client_i].fd != -1) {
close(pfds[client_i].fd);
DOLOG(info, false, "Restarting session for port %d", base_port + i + 1);
}
pfds[client_i].fd = accept(pfds[i].fd, nullptr, nullptr);
}
// receive data
for(int i=dc11_n_lines; i<dc11_n_lines * 2; i++) {
if (pfds[i].revents != POLLIN)
continue;
char buffer[32] { };
int rc = read(pfds[i].fd, buffer, sizeof buffer);
if (rc <= 0) { // closed or error?
DOLOG(info, false, "Failed reading on port %d", base_port + i + 1);
close(pfds[i].fd);
pfds[i].fd = -1;
}
else {
int line_nr = i - dc11_n_lines;
std::unique_lock<std::mutex> lck(input_lock[line_nr]);
for(int k=0; k<rc; k++)
recv_buffers[line_nr].push_back(buffer[k]);
have_data[line_nr].notify_all();
if (registers[line_nr * 4] & 64) // interrupts enabled?
b->getCpu()->queue_interrupt(4, 0320 + line_nr * 4);
}
}
}
for(int i=0; i<dc11_n_lines * 2; i++) {
if (fds[i] != -1)
close(fds[i]);
}
}
void dc11::reset()
{
}
uint8_t dc11::read_byte(const uint16_t addr)
{
uint16_t v = read_word(addr & ~1);
if (addr & 1)
return v >> 8;
return v;
}
uint16_t dc11::read_word(const uint16_t addr)
{
const int reg = (addr - DC11_BASE) / 2;
uint16_t vtemp = registers[reg];
DOLOG(debug, false, "DC11: read register %06o (%d): %06o", addr, reg, vtemp);
return vtemp;
}
void dc11::write_byte(const uint16_t addr, const uint8_t v)
{
uint16_t vtemp = registers[(addr - DC11_BASE) / 2];
if (addr & 1) {
vtemp &= ~0xff00;
vtemp |= v << 8;
}
else {
vtemp &= ~0x00ff;
vtemp |= v;
}
write_word(addr, vtemp);
}
void dc11::write_word(const uint16_t addr, uint16_t v)
{
const int reg = (addr - DC11_BASE) / 2;
DOLOG(debug, false, "DC11: write register %06o (%d) to %o", addr, reg, v);
registers[reg] = v;
}