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Author SHA1 Message Date
27174a1c79 feat: NOCD patch boots Havoc on modern Windows (defeats CD copy protection)
Diagnosed and fixed the crash that killed HAVOC_NOCD.EXE ~1s after launch
(dgVoodoo window appears black, then the process exits). It was not a clean
exit: an ACCESS_VIOLATION (null-pointer read at VA 0x444E6A) during init.

Root cause is a copy-protection check in the WORLDS\ data-file loader
(0x42a480). It opens each file (GRAFIX/LAND/MAP/STUF) from both a local
"WORLDS\<name>" path and a CD-drive path (HAVOC.INI [SETUP] DRIVE=D:\), and
returns a valid stream only when the local open fails and the CD-drive open
succeeds. With files present locally and no D: drive it returned NULL, and the
GRAFIX loader (0x444db0) dereferenced that NULL without checking.

Fix: 14-byte patch at FO 0x29a2b rewrites the return decision to hand back the
successfully-opened local object. The game now boots to the title screen
("HAVOC(tm) by Reality Bytes"), responsive, main loop running.

- docs/PATCHES.md: full patch table (28 patches) + crash write-up
- tools/: RE + patching scripts (r2pipe disasm, minidump parser, ctypes
  debugger, PE/IAT/import analysis)
- run_probe.bat / run_and_log.bat: reliable native launch for repro
- .gitignore: exclude CD images, Ghidra install/project, dgVoodoo, *.ini

Diagnosed via WER minidumps (%LOCALAPPDATA%\CrashDumps) parsed in pure Python
(no cdb/windbg available).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TN4Ytn3gdWRonNmHpisWQv
2026-07-03 09:29:59 -07:00
534c41af73 docs: add full RE methodology for blog post
Documents the process (not just the results) for each format cracked:
- Binary identification: why 32-bit PE not 16-bit, what actually broke
- .FF archive discovery: speculative parsing from file count heuristic
- MUSIC.FF playlists: big-endian payload in LE container, segment ID math
- INTRFACE.FF bitmaps: BitB/BitR/XPAL system, index-2 black patch discovery
Includes tools, dead ends, corrections (2D->3D), and what's next.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-06-29 00:29:50 -07:00