Mercurial > repos > blastem
view megawifi.c @ 2488:bfd09d3367ba
Fix crash when enabling VGM recording while running Pico or Copera software
author | Michael Pavone <pavone@retrodev.com> |
---|---|
date | Mon, 15 Apr 2024 23:07:18 -0700 |
parents | a8e3e816a50d |
children |
line wrap: on
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#include <stdlib.h> #include <stdint.h> #include <string.h> #include <sys/types.h> #ifdef _WIN32 #define WINVER 0x501 #include <winsock2.h> #include <ws2tcpip.h> #include <sys/param.h> #else #include <sys/socket.h> #include <arpa/inet.h> #include <unistd.h> #include <netinet/in.h> #include <netdb.h> #endif #include <errno.h> #include <fcntl.h> #include <time.h> #include "genesis.h" #include "net.h" #include "util.h" #if defined(_WIN32) || defined(__APPLE__) # if BYTE_ORDER == LITTLE_ENDIAN #define htobe64(val) ((((uint64_t)htonl((val)&0xFFFFFFFF))<<32) | htonl((val)>>32)) # else #define htobe64(val) (val) # endif #endif enum { TX_IDLE, TX_LEN1, TX_LEN2, TX_PAYLOAD, TX_WAIT_ETX }; #define STX 0x7E #define ETX 0x7E #define MAX_RECV_SIZE 1460 #define E(N) N enum { #include "mw_commands.c" CMD_ERROR = 255 }; #undef E #define E(N) #N static const char *cmd_names[] = { #include "mw_commands.c" [255] = "CMD_ERROR" }; #ifndef MSG_NOSIGNAL #define MSG_NOSIGNAL 0 #endif enum mw_state { STATE_IDLE=1, STATE_AP_JOIN, STATE_SCAN, STATE_READY, STATE_TRANSPARENT }; enum { SOCKST_NONE = 0, SOCKST_TCP_LISTEN, SOCKST_TCP_EST, SOCKST_UDP_READY }; // TCP/UDP address message struct mw_addr_msg { char dst_port[6]; char src_port[6]; uint8_t channel; char host[]; }; #define FLAG_ONLINE typedef struct { uint32_t transmit_bytes; uint32_t expected_bytes; uint32_t receive_bytes; uint32_t receive_read; int sock_fds[15]; uint16_t channel_flags; uint8_t channel_state[15]; uint8_t scratchpad; uint8_t transmit_channel; uint8_t transmit_state; uint8_t module_state; uint8_t flags; uint8_t transmit_buffer[4096]; uint8_t receive_buffer[4096]; struct sockaddr_in remote_addr[15]; // Needed for UDP sockets } megawifi; static megawifi *get_megawifi(void *context) { m68k_context *m68k = context; genesis_context *gen = m68k->system; if (!gen->extra) { socket_init(); gen->extra = calloc(1, sizeof(megawifi)); megawifi *mw = gen->extra; mw->module_state = STATE_IDLE; mw->flags = 0xE0; // cfg_ok, dt_ok, online for (int i = 0; i < 15; i++) { mw->sock_fds[i] = -1; } } return gen->extra; } static void mw_putc(megawifi *mw, uint8_t v) { if (mw->receive_bytes == sizeof(mw->receive_buffer)) { return; } mw->receive_buffer[mw->receive_bytes++] = v; } static void mw_set(megawifi *mw, uint8_t val, uint32_t count) { if (count + mw->receive_bytes > sizeof(mw->receive_buffer)) { count = sizeof(mw->receive_buffer) - mw->receive_bytes; } memset(mw->receive_buffer + mw->receive_bytes, val, count); mw->receive_bytes += count; } static void mw_copy(megawifi *mw, const uint8_t *src, uint32_t count) { if (count + mw->receive_bytes > sizeof(mw->receive_buffer)) { count = sizeof(mw->receive_buffer) - mw->receive_bytes; } memcpy(mw->receive_buffer + mw->receive_bytes, src, count); mw->receive_bytes += count; } static void mw_puts(megawifi *mw, const char *s) { size_t len = strlen(s); mw_copy(mw, (uint8_t*)s, len); } static void udp_recv(megawifi *mw, uint8_t idx) { ssize_t recvd; int s = mw->sock_fds[idx]; struct sockaddr_in remote; socklen_t addr_len = sizeof(struct sockaddr_in); if (mw->remote_addr[idx].sin_addr.s_addr != htonl(INADDR_ANY)) { // Receive only from specified address recvd = recvfrom(s, (char*)mw->receive_buffer + 3, MAX_RECV_SIZE, 0, (struct sockaddr*)&remote, &addr_len); if (recvd > 0) { if (remote.sin_addr.s_addr != mw->remote_addr[idx].sin_addr.s_addr) { printf("Discarding UDP packet from unknown addr %s:%d\n", inet_ntoa(remote.sin_addr), ntohs(remote.sin_port)); recvd = 0; } } } else { // Reuse mode, data is preceded by remote IPv4 and port recvd = recvfrom(s, (char*)mw->receive_buffer + 9, MAX_RECV_SIZE - 6, 0, (struct sockaddr*)&remote, &addr_len); if (recvd > 0) { mw->receive_buffer[3] = remote.sin_addr.s_addr; mw->receive_buffer[4] = remote.sin_addr.s_addr>>8; mw->receive_buffer[5] = remote.sin_addr.s_addr>>16; mw->receive_buffer[6] = remote.sin_addr.s_addr>>24; mw->receive_buffer[7] = remote.sin_port; mw->receive_buffer[8] = remote.sin_port>>8; recvd += 6; } } if (recvd > 0) { mw_putc(mw, STX); mw_putc(mw, (recvd >> 8) | ((idx+1) << 4)); mw_putc(mw, recvd); mw->receive_bytes += recvd; mw_putc(mw, ETX); //should this set the channel flag? } else if (recvd < 0 && !socket_error_is_wouldblock()) { socket_close(mw->sock_fds[idx]); mw->channel_state[idx] = SOCKST_NONE; mw->channel_flags |= 1 << (idx + 1); } } static void udp_send(megawifi *mw, uint8_t idx) { struct sockaddr_in remote; int s = mw->sock_fds[idx]; int sent; char *data = (char*)mw->transmit_buffer; if (mw->remote_addr[idx].sin_addr.s_addr != htonl(INADDR_ANY)) { sent = sendto(s, data, mw->transmit_bytes, 0, (struct sockaddr*)&mw->remote_addr[idx], sizeof(struct sockaddr_in)); } else { // Reuse mode, extract address from leading bytes // NOTE: mw->remote_addr[idx].sin_addr.s_addr == INADDR_ANY remote.sin_addr.s_addr = *((int32_t*)data); remote.sin_port = *((int16_t*)(data + 4)); remote.sin_family = AF_INET; memset(remote.sin_zero, 0, sizeof(remote.sin_zero)); sent = sendto(s, data + 6, mw->transmit_bytes - 6, 0, (struct sockaddr*)&remote, sizeof(struct sockaddr_in)) + 6; } if (sent < 0 && !socket_error_is_wouldblock()) { socket_close(s); mw->sock_fds[idx] = -1; mw->channel_state[idx] = SOCKST_NONE; mw->channel_flags |= 1 << (idx + 1); } else if (sent < mw->transmit_bytes) { //TODO: save this data somewhere so it can be sent in poll_socket printf("Sent %d bytes on channel %d, but %d were requested\n", sent, idx + 1, mw->transmit_bytes); } } static void poll_socket(megawifi *mw, uint8_t channel) { if (mw->sock_fds[channel] < 0) { return; } if (mw->channel_state[channel] == SOCKST_TCP_LISTEN) { int res = accept(mw->sock_fds[channel], NULL, NULL); if (res >= 0) { socket_close(mw->sock_fds[channel]); socket_blocking(res, 0); mw->sock_fds[channel] = res; mw->channel_state[channel] = SOCKST_TCP_EST; mw->channel_flags |= 1 << (channel + 1); } else if (errno != EAGAIN && errno != EWOULDBLOCK) { socket_close(mw->sock_fds[channel]); mw->channel_state[channel] = SOCKST_NONE; mw->channel_flags |= 1 << (channel + 1); } } else if (mw->channel_state[channel] == SOCKST_TCP_EST && mw->receive_bytes < (sizeof(mw->receive_buffer) - 4)) { size_t max = sizeof(mw->receive_buffer) - 4 - mw->receive_bytes; if (max > MAX_RECV_SIZE) { max = MAX_RECV_SIZE; } int bytes = recv(mw->sock_fds[channel], (char*)(mw->receive_buffer + mw->receive_bytes + 3), max, 0); if (bytes > 0) { mw_putc(mw, STX); mw_putc(mw, bytes >> 8 | (channel+1) << 4); mw_putc(mw, bytes); mw->receive_bytes += bytes; mw_putc(mw, ETX); //should this set the channel flag? } else if (bytes < 0 && !socket_error_is_wouldblock()) { socket_close(mw->sock_fds[channel]); mw->channel_state[channel] = SOCKST_NONE; mw->channel_flags |= 1 << (channel + 1); } } else if (mw->channel_state[channel] == SOCKST_UDP_READY && !mw->receive_bytes) { udp_recv(mw, channel); } } static void poll_all_sockets(megawifi *mw) { for (int i = 0; i < 15; i++) { poll_socket(mw, i); } } static void start_reply(megawifi *mw, uint8_t cmd) { mw_putc(mw, STX); //reserve space for length mw->receive_bytes += 2; //cmd mw_putc(mw, 0); mw_putc(mw, cmd); //reserve space for length mw->receive_bytes += 2; } static void end_reply(megawifi *mw) { uint32_t len = mw->receive_bytes - 3; //LSD packet length mw->receive_buffer[1] = len >> 8; mw->receive_buffer[2] = len; //command length len -= 4; mw->receive_buffer[5] = len >> 8; mw->receive_buffer[6] = len; mw_putc(mw, ETX); } static void cmd_ap_cfg_get(megawifi *mw) { char ssid[32] = {0}; char pass[64] = {0}; uint8_t slot = mw->transmit_buffer[4]; sprintf(ssid, "BLASTEM! SSID %d", slot + 1); sprintf(pass, "BLASTEM! PASS %d", slot + 1); start_reply(mw, CMD_OK); mw_putc(mw, slot); mw_putc(mw, 7); /// 11bgn mw_copy(mw, (uint8_t*)ssid, 32); mw_copy(mw, (uint8_t*)pass, 64); end_reply(mw); } static void cmd_ip_cfg_get(megawifi *mw) { uint32_t ipv4s[5] = {0}; start_reply(mw, CMD_OK); mw_putc(mw, mw->transmit_buffer[4]); mw_putc(mw, 0); mw_putc(mw, 0); mw_putc(mw, 0); mw_copy(mw, (uint8_t*)ipv4s, sizeof(ipv4s)); end_reply(mw); } static void cmd_tcp_con(megawifi *mw, uint32_t size) { struct mw_addr_msg *addr = (struct mw_addr_msg*)(mw->transmit_buffer + 4); struct addrinfo hints; struct addrinfo *res = NULL; int s; int err; uint8_t channel = addr->channel; if (!channel || channel > 15 || mw->sock_fds[channel - 1] >= 0) { start_reply(mw, CMD_ERROR); end_reply(mw); return; } channel--; memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_INET; #ifndef _WIN32 hints.ai_flags = AI_NUMERICSERV; #endif hints.ai_socktype = SOCK_STREAM; if ((err = getaddrinfo(addr->host, addr->dst_port, &hints, &res)) != 0) { printf("getaddrinfo failed: %s\n", gai_strerror(err)); start_reply(mw, CMD_ERROR); end_reply(mw); return; } s = socket(AF_INET, SOCK_STREAM, 0); if (s < 0) { goto err; } // Should this be handled in a separate thread to avoid blocking emulation? if (connect(s, res->ai_addr, res->ai_addrlen) != 0) { goto err; } socket_blocking(s, 0); mw->sock_fds[channel] = s; mw->channel_state[channel] = SOCKST_TCP_EST; mw->channel_flags |= 1 << (channel + 1); printf("Connection established on ch %d with %s:%s\n", channel + 1, addr->host, addr->dst_port); if (res) { freeaddrinfo(res); } start_reply(mw, CMD_OK); end_reply(mw); return; err: freeaddrinfo(res); printf("Connection to %s:%s failed, %s\n", addr->host, addr->dst_port, strerror(errno)); start_reply(mw, CMD_ERROR); end_reply(mw); } static void cmd_close(megawifi *mw) { int channel = mw->transmit_buffer[4] - 1; if (channel >= 15 || mw->sock_fds[channel] < 0) { start_reply(mw, CMD_ERROR); end_reply(mw); return; } socket_close(mw->sock_fds[channel]); mw->sock_fds[channel] = -1; mw->channel_state[channel] = SOCKST_NONE; mw->channel_flags |= 1 << (channel + 1); start_reply(mw, CMD_OK); end_reply(mw); } static void cmd_udp_set(megawifi *mw) { struct mw_addr_msg *addr = (struct mw_addr_msg*)(mw->transmit_buffer + 4); unsigned int local_port, remote_port; int s; struct addrinfo *raddr; struct addrinfo hints; struct sockaddr_in local; int err; uint8_t channel = addr->channel; if (!channel || channel > 15 || mw->sock_fds[channel - 1] >= 0) { goto err; } channel--; local_port = atoi(addr->src_port); remote_port = atoi(addr->dst_port); if ((s = socket(PF_INET, SOCK_DGRAM, 0)) < 0) { printf("Datagram socket creation failed\n"); goto err; } memset(local.sin_zero, 0, sizeof(local.sin_zero)); local.sin_family = AF_INET; local.sin_addr.s_addr = htonl(INADDR_ANY); local.sin_port = htons(local_port); if (remote_port && addr->host[0]) { // Communication with remote peer printf("Set UDP ch %d, port %d to addr %s:%d\n", addr->channel, local_port, addr->host, remote_port); memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_INET; #ifndef _WIN32 hints.ai_flags = AI_NUMERICSERV; #endif hints.ai_socktype = SOCK_DGRAM; if ((err = getaddrinfo(addr->host, addr->dst_port, &hints, &raddr)) != 0) { printf("getaddrinfo failed: %s\n", gai_strerror(err)); goto err; } mw->remote_addr[channel] = *((struct sockaddr_in*)raddr->ai_addr); freeaddrinfo(raddr); } else if (local_port) { // Server in reuse mode printf("Set UDP ch %d, src port %d\n", addr->channel, local_port); mw->remote_addr[channel] = local; } else { printf("Invalid UDP socket data\n"); goto err; } if (bind(s, (struct sockaddr*)&local, sizeof(struct sockaddr_in)) < 0) { printf("bind to port %d failed\n", local_port); goto err; } socket_blocking(s, 0); mw->sock_fds[channel] = s; mw->channel_state[channel] = SOCKST_UDP_READY; mw->channel_flags |= 1 << (channel + 1); start_reply(mw, CMD_OK); end_reply(mw); return; err: start_reply(mw, CMD_ERROR); end_reply(mw); } #define AVATAR_BYTES (32 * 48 / 2) static void cmd_gamertag_get(megawifi *mw) { uint32_t id = htonl(1); char buf[AVATAR_BYTES]; start_reply(mw, CMD_OK); // TODO Get items from config file mw_copy(mw, (uint8_t*)&id, 4); strncpy(buf, "doragasu on Blastem!", 32); mw_copy(mw, (uint8_t*)buf, 32); strncpy(buf, "My cool password", 32); mw_copy(mw, (uint8_t*)buf, 32); strncpy(buf, "All your WiFi are belong to me!", 32); mw_copy(mw, (uint8_t*)buf, 32); memset(buf, 0, 64); // Telegram token mw_copy(mw, (uint8_t*)buf, 64); mw_copy(mw, (uint8_t*)buf, AVATAR_BYTES); // Avatar tiles mw_copy(mw, (uint8_t*)buf, 32); // Avatar palette end_reply(mw); } static void cmd_hrng_get(megawifi *mw) { uint16_t len = (mw->transmit_buffer[4]<<8) + mw->transmit_buffer[5]; if (len > (MAX_RECV_SIZE - 4)) { start_reply(mw, CMD_ERROR); end_reply(mw); return; } // Pseudo-random, but who cares start_reply(mw, CMD_OK); srand(time(NULL)); for (uint16_t i = 0; i < len; i++) { mw_putc(mw, rand()); } end_reply(mw); } static void cmd_datetime(megawifi *mw) { start_reply(mw, CMD_OK); #ifdef _WIN32 __time64_t t = _time64(NULL); int64_t t_be = htobe64(t); mw_copy(mw, (uint8_t*)&t_be, sizeof(int64_t)); mw_puts(mw, _ctime64(&t)); #else time_t t = time(NULL); int64_t t_be = htobe64(t); mw_copy(mw, (uint8_t*)&t_be, sizeof(int64_t)); mw_puts(mw, ctime(&t)); #endif mw_putc(mw, '\0'); end_reply(mw); } static void process_command(megawifi *mw) { uint32_t command = mw->transmit_buffer[0] << 8 | mw->transmit_buffer[1]; uint32_t size = mw->transmit_buffer[2] << 8 | mw->transmit_buffer[3]; if (size > mw->transmit_bytes - 4) { size = mw->transmit_bytes - 4; } int orig_receive_bytes = mw->receive_bytes; switch (command) { case CMD_VERSION: start_reply(mw, CMD_OK); mw_putc(mw, 1); mw_putc(mw, 3); mw_putc(mw, 0); mw_puts(mw, "blastem"); mw_putc(mw, '\0'); end_reply(mw); break; case CMD_ECHO: mw->receive_bytes = mw->transmit_bytes; memcpy(mw->receive_buffer, mw->transmit_buffer, mw->transmit_bytes); break; case CMD_AP_CFG_GET: cmd_ap_cfg_get(mw); break; case CMD_IP_CURRENT: { iface_info i; if (get_host_address(&i)) { start_reply(mw, CMD_OK); //config number and reserved bytes mw_set(mw, 0, 4); //ip mw_copy(mw, i.ip, sizeof(i.ip)); //net mask mw_copy(mw, i.net_mask, sizeof(i.net_mask)); //gateway guess mw_putc(mw, i.ip[0] & i.net_mask[0]); mw_putc(mw, i.ip[1] & i.net_mask[1]); mw_putc(mw, i.ip[2] & i.net_mask[2]); mw_putc(mw, (i.ip[3] & i.net_mask[3]) + 1); //dns static const uint8_t localhost[] = {127,0,0,1}; mw_copy(mw, localhost, sizeof(localhost)); mw_copy(mw, localhost, sizeof(localhost)); } else { start_reply(mw, CMD_ERROR); } end_reply(mw); break; } case CMD_IP_CFG_GET: cmd_ip_cfg_get(mw); break; case CMD_DEF_AP_CFG_GET: start_reply(mw, CMD_OK); mw_putc(mw, 0); end_reply(mw); break; case CMD_AP_JOIN: mw->module_state = STATE_READY; start_reply(mw, CMD_OK); end_reply(mw); break; case CMD_TCP_CON: cmd_tcp_con(mw, size); break; case CMD_TCP_BIND:{ if (size < 7){ start_reply(mw, CMD_ERROR); end_reply(mw); break; } uint8_t channel = mw->transmit_buffer[10]; if (!channel || channel > 15) { start_reply(mw, CMD_ERROR); end_reply(mw); break; } channel--; if (mw->sock_fds[channel] >= 0) { socket_close(mw->sock_fds[channel]); } mw->sock_fds[channel] = socket(AF_INET, SOCK_STREAM, 0); if (mw->sock_fds[channel] < 0) { start_reply(mw, CMD_ERROR); end_reply(mw); break; } int value = 1; setsockopt(mw->sock_fds[channel], SOL_SOCKET, SO_REUSEADDR, (char*)&value, sizeof(value)); struct sockaddr_in bind_addr; memset(&bind_addr, 0, sizeof(bind_addr)); bind_addr.sin_family = AF_INET; bind_addr.sin_port = htons(mw->transmit_buffer[8] << 8 | mw->transmit_buffer[9]); if (bind(mw->sock_fds[channel], (struct sockaddr *)&bind_addr, sizeof(bind_addr)) != 0) { socket_close(mw->sock_fds[channel]); mw->sock_fds[channel] = -1; start_reply(mw, CMD_ERROR); end_reply(mw); break; } int res = listen(mw->sock_fds[channel], 2); start_reply(mw, res ? CMD_ERROR : CMD_OK); if (res) { socket_close(mw->sock_fds[channel]); mw->sock_fds[channel] = -1; } else { mw->channel_flags |= 1 << (channel + 1); mw->channel_state[channel] = SOCKST_TCP_LISTEN; socket_blocking(mw->sock_fds[channel], 0); } end_reply(mw); break; } case CMD_CLOSE: cmd_close(mw); break; case CMD_UDP_SET: cmd_udp_set(mw); break; case CMD_SOCK_STAT: { uint8_t channel = mw->transmit_buffer[4]; if (!channel || channel > 15) { start_reply(mw, CMD_ERROR); end_reply(mw); break; } mw->channel_flags &= ~(1 << channel); channel--; poll_socket(mw, channel); start_reply(mw, CMD_OK); mw_putc(mw, mw->channel_state[channel]); end_reply(mw); break; } case CMD_DATETIME: cmd_datetime(mw); break; case CMD_SYS_STAT: poll_all_sockets(mw); start_reply(mw, CMD_OK); mw_putc(mw, mw->module_state); mw_putc(mw, mw->flags); mw_putc(mw, mw->channel_flags >> 8); mw_putc(mw, mw->channel_flags); end_reply(mw); break; case CMD_GAMERTAG_GET: cmd_gamertag_get(mw); break; case CMD_LOG: start_reply(mw, CMD_OK); puts((char*)&mw->transmit_buffer[4]); end_reply(mw); break; case CMD_HRNG_GET: cmd_hrng_get(mw); break; case CMD_SERVER_URL_GET: start_reply(mw, CMD_OK); // FIXME: This should be get from config file mw_puts(mw, "doragasu.com"); mw_putc(mw,'\0'); end_reply(mw); break; default: printf("Unhandled MegaWiFi command %s(%d) with length %X\n", cmd_names[command], command, size); break; } } static void process_packet(megawifi *mw) { if (mw->transmit_channel == 0) { process_command(mw); } else { uint8_t channel = mw->transmit_channel - 1; int channel_state = mw->channel_state[channel]; int sock_fd = mw->sock_fds[channel]; if (sock_fd >= 0 && channel_state == SOCKST_TCP_EST) { int sent = send(sock_fd, (char*)mw->transmit_buffer, mw->transmit_bytes, 0); if (sent < 0 && !socket_error_is_wouldblock()) { socket_close(sock_fd); mw->sock_fds[channel] = -1; mw->channel_state[channel] = SOCKST_NONE; mw->channel_flags |= 1 << mw->transmit_channel; } else if (sent < mw->transmit_bytes) { //TODO: save this data somewhere so it can be sent in poll_socket printf("Sent %d bytes on channel %d, but %d were requested\n", sent, mw->transmit_channel, mw->transmit_bytes); } } else if (sock_fd >= 0 && channel_state == SOCKST_UDP_READY) { udp_send(mw, channel); } else { printf("Unhandled receive of MegaWiFi data on channel %d\n", mw->transmit_channel); } } mw->transmit_bytes = mw->expected_bytes = 0; } void *megawifi_write_b(uint32_t address, void *context, uint8_t value) { if (!(address & 1)) { return context; } megawifi *mw = get_megawifi(context); address = address >> 1 & 7; switch (address) { case 0: switch (mw->transmit_state) { case TX_IDLE: if (value == STX) { mw->transmit_state = TX_LEN1; } break; case TX_LEN1: mw->transmit_channel = value >> 4; mw->expected_bytes = value << 8 & 0xF00; mw->transmit_state = TX_LEN2; break; case TX_LEN2: mw->expected_bytes |= value; mw->transmit_state = TX_PAYLOAD; break; case TX_PAYLOAD: mw->transmit_buffer[mw->transmit_bytes++] = value; if (mw->transmit_bytes == mw->expected_bytes) { mw->transmit_state = TX_WAIT_ETX; } break; case TX_WAIT_ETX: if (value == ETX) { mw->transmit_state = TX_IDLE; process_packet(mw); } break; } break; case 7: mw->scratchpad = value; break; default: printf("Unhandled write to MegaWiFi UART register %X: %X\n", address, value); } return context; } void *megawifi_write_w(uint32_t address, void *context, uint16_t value) { return megawifi_write_b(address | 1, context, value); } uint8_t megawifi_read_b(uint32_t address, void *context) { if (!(address & 1)) { return 0xFF; } megawifi *mw = get_megawifi(context); address = address >> 1 & 7; switch (address) { case 0: poll_all_sockets(mw); if (mw->receive_read < mw->receive_bytes) { uint8_t ret = mw->receive_buffer[mw->receive_read++]; if (mw->receive_read == mw->receive_bytes) { mw->receive_read = mw->receive_bytes = 0; } return ret; } return 0xFF; case 5: poll_all_sockets(mw); //line status return 0x60 | (mw->receive_read < mw->receive_bytes); case 7: return mw->scratchpad; default: printf("Unhandled read from MegaWiFi UART register %X\n", address); return 0xFF; } } uint16_t megawifi_read_w(uint32_t address, void *context) { return 0xFF00 | megawifi_read_b(address | 1, context); }