From 080bf456d6635d14c9668bb6691fca04e0409f75 Mon Sep 17 00:00:00 2001
From: Toni Wilen <twilen@winuae.net>
Date: Sun, 30 Apr 2023 21:10:59 +0300
Subject: [PATCH] inter-process serial port stability fix, status signal and
 break support.

---
 od-win32/serial_win32.cpp | 117 +++++++++++++++++++++++++++++++++-----
 1 file changed, 102 insertions(+), 15 deletions(-)

diff --git a/od-win32/serial_win32.cpp b/od-win32/serial_win32.cpp
index 448ea8d7..bbb0e18e 100644
--- a/od-win32/serial_win32.cpp
+++ b/od-win32/serial_win32.cpp
@@ -49,13 +49,14 @@ struct sermap_buffer
 	volatile uae_u32 active_write;
 	volatile uae_u32 read_offset;
 	volatile uae_u32 write_offset;
-	volatile uae_u16 data[SERMAP_SIZE];
+	volatile uae_u32 data[SERMAP_SIZE];
 };
 static struct sermap_buffer *sermap1, *sermap2;
 static HANDLE sermap_handle;
 static uae_u8 *sermap_data;
 static bool sermap_master;
 static bool sermap_enabled;
+static uae_u32 sermap_flags;
 static bool serloop_enabled;
 static bool serempty_enabled;
 static bool serxdevice_enabled;
@@ -66,7 +67,7 @@ static int receive_buf_size, receive_buf_count;
 
 #define SER_MEMORY_MAPPING _T("WinUAE_Serial")
 
-static void shmem_serial_send(uae_u16 data)
+static void shmem_serial_send(uae_u32 data)
 {
 	uae_u32 v;
 
@@ -83,16 +84,16 @@ static void shmem_serial_send(uae_u16 data)
 	v &= (SERMAP_SIZE - 1);
 	sermap1->write_offset = v;
 }
-static uae_u16 shmem_serial_receive(void)
+static uae_u32 shmem_serial_receive(void)
 {
 	uae_u32 v;
-	uae_u16 data;
+	uae_u32 data;
 	sermap2->active_read = true;
 	if (!sermap2->active_write)
-		return 0xffff;
+		return 0xffffffff;
 	v = sermap2->read_offset;
 	if (v == sermap2->write_offset)
-		return 0xffff;
+		return 0xffffffff;
 	data = sermap2->data[v];
 	v++;
 	v &= (SERMAP_SIZE - 1);
@@ -103,6 +104,7 @@ static uae_u16 shmem_serial_receive(void)
 static void sermap_deactivate(void)
 {
 	sermap_enabled = false;
+	sermap_flags = 0;
 	if (sermap1) {
 		sermap1->active_write = 0;
 		sermap1->write_offset = sermap1->read_offset;
@@ -604,8 +606,9 @@ static void checksend(void)
 		return;
 	}
 #ifdef SERIAL_MAP
-	if (sermap_data && sermap_enabled)
+	if (sermap_data && sermap_enabled) {
 		shmem_serial_send(serdatshift);
+	}
 #endif
 #ifdef SERIAL_ENET
 	if (serial_enet) {
@@ -814,21 +817,62 @@ void serial_hsynchandler (void)
 		}
 	}
 
-	if (lastbitcycle_active_hsyncs > 0)
+	if (lastbitcycle_active_hsyncs > 0) {
 		lastbitcycle_active_hsyncs--;
+	}
 #ifdef SERIAL_MAP
-	if (sermap2 && sermap_enabled && !data_in_serdatr) {
-		uae_u16 v = shmem_serial_receive();
-		if (v != 0xffff) {
-			serdatr = v;
+	if (sermap2 && sermap_enabled) {
+		if (!data_in_serdatr) {
+			for (;;) {
+				uae_u32 v = shmem_serial_receive();
+				if (v == 0xffffffff) {
+					break;
+				}
+				if (!(v & 0xffff0000)) {
+					serdatr = (uae_u16)v;
+					serial_rx_irq();
+					break;
+				} else if ((v & 0x80000000) == 0x80000000) {
+					sermap_flags &= 0x0fff0000;
+					sermap_flags |= v & 0xffff;
+				} else if ((v & 0x40000000) == 0x40000000) {
+					if (v & (0x10000 | 0x20000)) {
+						sermap_flags &= ~(0x10000 | 0x20000);
+						sermap_flags |= v & (0x10000 | 0x20000);
+						break;
+					}
+				}
+			}
+		}
+		// break on
+		if (sermap_flags & 0x20000) {
+			break_in_serdatr = maxvpos;
+		}
+		if (break_in_serdatr) {
+			serdatr = 0;
+			if (break_delay == 0) {
+				serial_rx_irq();
+				break_delay = SERIAL_BREAK_TRANSMIT_DELAY;
+			}
+			if (break_delay > 0) {
+				break_delay--;
+			}
+		}
+		// break off
+		if (break_in_serdatr == 1) {
+			break_in_serdatr = 0;
+			break_delay = 0;
+			serdatr |= 0x100;
 			serial_rx_irq();
 		}
 	}
 #endif
-	if (data_in_serdatr)
+	if (data_in_serdatr) {
 		serdatr_last_got++;
-	if (serial_period_hsyncs == 0)
+	}
+	if (serial_period_hsyncs == 0) {
 		return;
+	}
 	serial_period_hsync_counter++;
 	if (serial_period_hsyncs == 1 || (serial_period_hsync_counter % (serial_period_hsyncs - 1)) == 0) {
 		checkreceive_serial();
@@ -1026,6 +1070,18 @@ uae_u8 serial_readstatus(uae_u8 v, uae_u8 dir)
 		if (ri) {
 			status |= TIOCM_RI;
 		}
+#ifdef SERIAL_MAP
+	} else if (sermap_enabled) {
+		if (sermap_flags & 1) {
+			status |= TIOCM_DSR;
+		}
+		if (sermap_flags & 2) {
+			status |= TIOCM_CAR;
+		}
+		if (sermap_flags & 4) {
+			status |= TIOCM_CTS;
+		}
+#endif
 	} else if (currprefs.use_serial) {
 #ifdef SERIAL_PORT
 		getserstat(&status);
@@ -1164,6 +1220,32 @@ uae_u8 serial_writestatus (uae_u8 newstate, uae_u8 dir)
 		}
 	}
 
+#ifdef SERIAL_MAP
+	if (sermap_data && sermap_enabled) {
+		uae_u32 flags = 0x80000000;
+		bool changed = false;
+		if (((oldserbits ^ newstate) & 0x80) && (dir & 0x80)) {
+			if (!(newstate & 0x80)) {
+				flags |= 1; // DSR
+				flags |= 2; // CD
+			}
+			changed = true;
+		}
+		if (!currprefs.serial_hwctsrts && (dir & 0x40)) {
+			if ((oldserbits ^ newstate) & 0x40) {
+				if (!(newstate & 0x40)) {
+					flags |= 4; // RTS
+				}
+				changed = true;
+			}
+		}
+		if (changed) {
+			shmem_serial_send(flags);
+		}
+	}
+#endif
+
+
 	oldserbits &= ~(0x80 | 0x40);
 	newstate &= 0x80 | 0x40;
 	oldserbits |= newstate;
@@ -1203,7 +1285,7 @@ void serial_open (void)
 			return;
 		}
 	}
-	if (alg_flag || currprefs.genlock_image >= 7 || cubo_enabled) {
+	if (alg_flag || currprefs.genlock_image >= 7 || cubo_enabled || sermap_enabled || rp_ismodem()) {
 		serxdevice_enabled = true;
 	}
 	serdev = 1;
@@ -1272,6 +1354,11 @@ void serial_exit (void)
 
 void serial_uartbreak (int v)
 {
+#ifdef SERIAL_MAP
+	if (sermap_data && sermap_enabled) {
+		shmem_serial_send(0x40000000 | (v ? 0x20000 : 0x10000));
+	}
+#endif
 #ifdef SERIAL_PORT
 	serialuartbreak (v);
 #endif
-- 
2.47.3