From a630855b7e5849243217a50575c2024fb2d1ec86 Mon Sep 17 00:00:00 2001
From: Scott Duensing <scott@duensing.com>
Date: Thu, 26 Mar 2026 21:39:03 -0500
Subject: [PATCH] Serial libraries added to DVX.

---
 Makefile                       |  8 +++--
 config/serial.dep              |  2 ++
 core/platform/dvxPlatformDos.c | 14 +++++++++
 serial/Makefile                | 56 ++++++++++++++++++++++++++++++++++
 4 files changed, 78 insertions(+), 2 deletions(-)
 create mode 100644 config/serial.dep
 create mode 100644 serial/Makefile

diff --git a/Makefile b/Makefile
index 6e1ee64..12cbb6d 100644
--- a/Makefile
+++ b/Makefile
@@ -3,9 +3,9 @@
 # Builds the full DVX stack: core library, task switcher,
 # bootstrap loader, text help library, widgets, shell, and apps.
 
-.PHONY: all clean core tasks loader texthelp listhelp widgets shell taskmgr apps tools
+.PHONY: all clean core tasks loader texthelp listhelp widgets shell taskmgr serial apps tools
 
-all: core tasks loader texthelp listhelp widgets shell taskmgr apps tools
+all: core tasks loader texthelp listhelp widgets shell taskmgr serial apps tools
 
 core:
 	$(MAKE) -C core
@@ -31,6 +31,9 @@ shell: core tasks
 taskmgr: shell
 	$(MAKE) -C taskmgr
 
+serial: core tasks
+	$(MAKE) -C serial
+
 tools:
 	$(MAKE) -C tools
 
@@ -46,6 +49,7 @@ clean:
 	$(MAKE) -C widgets clean
 	$(MAKE) -C shell clean
 	$(MAKE) -C taskmgr clean
+	$(MAKE) -C serial clean
 	$(MAKE) -C apps clean
 	$(MAKE) -C tools clean
 	-rmdir obj 2>/dev/null
diff --git a/config/serial.dep b/config/serial.dep
new file mode 100644
index 0000000..2afaca0
--- /dev/null
+++ b/config/serial.dep
@@ -0,0 +1,2 @@
+libtasks
+libdvx
diff --git a/core/platform/dvxPlatformDos.c b/core/platform/dvxPlatformDos.c
index 86e56ff..216a9f4 100644
--- a/core/platform/dvxPlatformDos.c
+++ b/core/platform/dvxPlatformDos.c
@@ -2323,6 +2323,10 @@ extern void *__emutls_get_address(void *);
 // dvxLog lives in dvx.exe (loaderMain.c)
 extern void dvxLog(const char *fmt, ...);
 
+// DPMI/go32 internals needed by the serial driver (rs232)
+#include <dpmi.h>
+#include <go32.h>
+
 extern void  *stbds_arrgrowf(void *a, size_t elemsize, size_t addlen, size_t min_cap);
 extern void   stbds_arrfreef(void *a);
 extern void   stbds_hmfree_func(void *a, size_t elemsize);
@@ -2389,6 +2393,16 @@ DXE_EXPORT_TABLE(sDxeExportTable)
     // --- dvx logging (lives in dvx.exe, used by all modules) ---
     DXE_EXPORT(dvxLog)
 
+    // --- DPMI/go32 (needed by rs232 serial driver) ---
+    DXE_EXPORT(__dpmi_get_segment_base_address)
+    DXE_EXPORT(__dpmi_lock_linear_region)
+    DXE_EXPORT(__dpmi_unlock_linear_region)
+    DXE_EXPORT(_go32_dpmi_allocate_iret_wrapper)
+    DXE_EXPORT(_go32_dpmi_free_iret_wrapper)
+    DXE_EXPORT(_go32_dpmi_get_protected_mode_interrupt_vector)
+    DXE_EXPORT(_go32_dpmi_set_protected_mode_interrupt_vector)
+    DXE_EXPORT(_go32_info_block)
+
     // --- memory ---
     // --- memory (tracked wrappers replace libc for DXE code) ---
     { "_calloc",  (void *)dvxCalloc },
diff --git a/serial/Makefile b/serial/Makefile
new file mode 100644
index 0000000..f6faa57
--- /dev/null
+++ b/serial/Makefile
@@ -0,0 +1,56 @@
+# DVX Serial Stack Makefile for DJGPP cross-compilation
+#
+# Builds serial.lib -- combines rs232, packet, security, and seclink
+# into a single DXE library loaded by the DVX system.
+
+DJGPP_PREFIX  = $(HOME)/djgpp/djgpp
+CC            = $(DJGPP_PREFIX)/bin/i586-pc-msdosdjgpp-gcc
+DXE3GEN       = PATH=$(DJGPP_PREFIX)/bin:$(PATH) DJDIR=$(DJGPP_PREFIX)/i586-pc-msdosdjgpp $(DJGPP_PREFIX)/i586-pc-msdosdjgpp/bin/dxe3gen
+CFLAGS        = -O2 -Wall -Wextra -march=i486 -mtune=i586 -I../rs232 -I../packet -I../security -I../seclink -I../core -I../core/platform -I../tasks
+
+OBJDIR  = ../obj/serial
+LIBSDIR = ../bin/libs
+
+SRCS = ../rs232/rs232.c ../packet/packet.c ../security/security.c ../seclink/secLink.c
+OBJS = $(OBJDIR)/rs232.o $(OBJDIR)/packet.o $(OBJDIR)/security.o $(OBJDIR)/secLink.o
+TARGET = $(LIBSDIR)/serial.lib
+
+.PHONY: all clean
+
+all: $(TARGET) $(LIBSDIR)/serial.dep
+
+$(LIBSDIR)/serial.dep: ../config/serial.dep | $(LIBSDIR)
+	sed 's/$$/\r/' $< > $@
+
+$(TARGET): $(OBJS) | $(LIBSDIR)
+	$(DXE3GEN) -o $(LIBSDIR)/serial.dxe \
+		-E _rs232 -E _pkt -E _secLink -E _secDh -E _secCipher -E _secRng \
+		-U $(OBJS)
+	mv $(LIBSDIR)/serial.dxe $@
+
+$(OBJDIR)/rs232.o: ../rs232/rs232.c | $(OBJDIR)
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+$(OBJDIR)/packet.o: ../packet/packet.c | $(OBJDIR)
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+$(OBJDIR)/security.o: ../security/security.c | $(OBJDIR)
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+$(OBJDIR)/secLink.o: ../seclink/secLink.c | $(OBJDIR)
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+$(OBJDIR):
+	mkdir -p $(OBJDIR)
+
+$(LIBSDIR):
+	mkdir -p $(LIBSDIR)
+
+# Dependencies
+$(OBJDIR)/rs232.o: ../rs232/rs232.c ../rs232/rs232.h
+$(OBJDIR)/packet.o: ../packet/packet.c ../packet/packet.h ../rs232/rs232.h
+$(OBJDIR)/security.o: ../security/security.c ../security/security.h
+$(OBJDIR)/secLink.o: ../seclink/secLink.c ../seclink/secLink.h ../rs232/rs232.h ../packet/packet.h ../security/security.h
+
+clean:
+	rm -f $(OBJS) $(TARGET) $(LIBSDIR)/serial.dep