setque (called by USER.EXE after every inicom) was running GlobalAlloc and
GlobalFree with interrupts disabled. On the second open the global heap
could need compaction or DPMI selector work, deadlocking under CLI.
Restructured to allocate new buffers first, swap pointers under CLI, then
free old buffers after STI.
Ring buffers changed from GMEM_MOVEABLE to GMEM_FIXED so addresses are
inherently stable at interrupt time. Added rxBufH/txBufH handle fields
to PortStateT, eliminating the fragile GlobalHandle(SELECTOROF()) recovery
in freeBuffers.
trmcom now resets FIFOs and drains all pending UART conditions (LSR, MSR,
RBR, IIR) before unhooking the ISR, leaving hardware clean for reopen.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Separate parsing from rendering to eliminate per-character GDI calls.
ProcessChar now only updates cell data in memory; rendering is deferred
to FlipToScreen which batches consecutive same-color cells into single
TextOut calls (~5-10 per row instead of 80). Partial BitBlt transfers
only the dirty row band to the screen. Non-blinking rows render to one
buffer and BitBlt to the second, halving GDI work for typical content.
Also removes redundant GetCommError from KPComm receive path and adds
BeginUpdate/EndUpdate batching in the test app's CommEvent handler.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Resolve GPFs in both USER.EXE and COMMTASK.DLL by correcting RETF
sizes for SETCOM and GETDCB, confirmed by disassembling CyberCom.DRV.
Add stock-compatible ComDEB structure so third-party code (ProComm
COMMTASK.DLL) can safely access internal fields at known offsets per
Microsoft KB Q101417.
COMM.DRV changes:
- SETCOM (ord 2): RETF 4, takes DCB FAR * only (not commId + DCB*)
- GETDCB (ord 15): RETF 2, takes commId, returns DCB FAR * in DX:AX
- Add 40-byte ComDebT matching stock COMM.DRV internal layout
(evtWord at +0, MSR shadow at +35, queue counts at +8/+18)
- cevt returns pointer to ComDebT for third-party compatibility
- Sync ComDEB fields in ISR dispatch, reccom, sndcom, cflush, setque
- Move WEP to ordinal 16, add ordinal 101 stub (match stock/CyberCom)
- Default DBG_ENABLED to 0 (set to 1 to re-enable debug logging)
VBX control fixes:
- Fix SETBREAK/CLRBREAK constants (use numeric 8/9, not undefined macros)
- Fix serialEnableNotify return type (BOOL, not int16_t)
- Fix mscomm.h to work with RC compiler (#ifndef RC_INVOKED)
- Fix vbapi.h USHORT typedef and MODEL.flWndStyle type
- Add vbapi.lib dependency to makefile
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
