Initial commit — leak-hunt project complete

Five bugs identified and patched in retail Asheron's Call client:
- v3b: palette refcount over-increment (3-byte NOP at two sites)
- v5: RenderSurface PurgeResource no-op stub (vtable slot 2 thunk)
- v11: two dangling-pointer crash guards (NULL-check + reorder)
- v14: CEnvCell::Destroy ClipPlaneList leak (18-byte JMP to cleanup thunk)
- v22: unpacker stale-pointer SEH guard (whole-function __try/__except)

All five ship in leakfix.dll (117 KB, SHA d282f23c…) which is loaded
by acclient.exe at process start via PE import table patching by
tools/install_leakfix.py.

Controlled 15-client fleet soak: unpatched control died at 26h with
palette exhaustion; all 14 patched clients survived past that point
and reached ≥5-day uptime.

Residual ~15 MB/h growth traced to d3d9.dll's internal slab allocator
(260KB surface backing buffers retained after Release). See REPORT.md
§10 for the full investigation; conclusion is that it's unfixable from
outside d3d9.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tools/check_patch_state.py

@@ -0,0 +1,102 @@
+"""check_patch_state.py [pid1 pid2 ...]
+
+Check which patches are applied to each AC client. If no PIDs given,
+scans all acclient processes.
+"""
+import argparse, ctypes, ctypes.wintypes as wt, subprocess, sys
+
+
+SITES = {
+    "v3b-1":  (0x0053effe, bytes([0xff, 0x40, 0x24]), bytes([0x90, 0x90, 0x90])),
+    "v3b-2":  (0x0053f19c, bytes([0xff, 0x46, 0x24]), bytes([0x90, 0x90, 0x90])),
+    "v4":     (0x007ca444, bytes([0xa0, 0x54, 0x41, 0x00]), None),  # CGfxObj vtable slot 11
+    "v5-RS":  (0x0079a684, bytes([0xa0, 0x54, 0x41, 0x00]), None),  # RenderSurface vtable slot 2
+    "v5-RT":  (0x0079c1a0, bytes([0xa0, 0x54, 0x41, 0x00]), None),  # RenderTexture vtable slot 2
+    "v8-1":   (0x004e439d, bytes([0x0f, 0x84, 0xf3, 0x01, 0x00, 0x00]), bytes([0x90, 0x90, 0x90, 0x90, 0x90, 0x90])),
+    "v8-2":   (0x004e43c0, bytes([0x0f, 0x85, 0xcd, 0x01, 0x00, 0x00]), bytes([0x90, 0x90, 0x90, 0x90, 0x90, 0x90])),
+    "v8-3":   (0x004e4496, bytes([0x75, 0x0d]), bytes([0x75, 0x08])),
+}
+
+
+PROCESS_VM_READ = 0x10
+PROCESS_QUERY_INFORMATION = 0x400
+
+
+k = ctypes.windll.kernel32
+k.OpenProcess.argtypes = [wt.DWORD, wt.BOOL, wt.DWORD]; k.OpenProcess.restype = wt.HANDLE
+k.CloseHandle.argtypes = [wt.HANDLE]; k.CloseHandle.restype = wt.BOOL
+k.ReadProcessMemory.argtypes = [wt.HANDLE, wt.LPCVOID, wt.LPVOID, ctypes.c_size_t,
+                                ctypes.POINTER(ctypes.c_size_t)]
+k.ReadProcessMemory.restype = wt.BOOL
+
+
+def read_bytes(h, addr, n):
+    buf = (ctypes.c_ubyte * n)()
+    sz = ctypes.c_size_t(0)
+    if not k.ReadProcessMemory(h, addr, buf, n, ctypes.byref(sz)):
+        return None
+    return bytes(buf[:sz.value])
+
+
+def check_pid(pid):
+    h = k.OpenProcess(PROCESS_VM_READ | PROCESS_QUERY_INFORMATION, False, pid)
+    if not h:
+        return None
+    result = {}
+    for name, (addr, orig, patched) in SITES.items():
+        cur = read_bytes(h, addr, len(orig))
+        if cur is None:
+            result[name] = "?"
+        elif cur == orig:
+            result[name] = "."   # unpatched / original
+        elif patched is not None and cur == patched:
+            result[name] = "P"
+        else:
+            result[name] = "X"   # different (could be runtime-allocated thunk addr for v4/v5)
+    k.CloseHandle(h)
+    return result
+
+
+def get_window_title(pid):
+    try:
+        out = subprocess.check_output(
+            ["powershell.exe", "-NoProfile", "-Command",
+             f"(Get-Process -Id {pid} -ErrorAction SilentlyContinue).MainWindowTitle"],
+            text=True, stderr=subprocess.DEVNULL).strip()
+        return out.split("-")[-1].strip() if out else ""
+    except Exception:
+        return ""
+
+
+def list_acclient_pids():
+    try:
+        out = subprocess.check_output(
+            ["powershell.exe", "-NoProfile", "-Command",
+             "(Get-Process acclient -ErrorAction SilentlyContinue).Id"],
+            text=True, stderr=subprocess.DEVNULL).strip()
+        return sorted(int(line) for line in out.splitlines() if line.strip())
+    except Exception:
+        return []
+
+
+ap = argparse.ArgumentParser()
+ap.add_argument("pids", type=int, nargs="*")
+args = ap.parse_args()
+
+pids = args.pids if args.pids else list_acclient_pids()
+
+cols = list(SITES.keys())
+print(f"{'pid':>6}  {'  '.join(c[:6] for c in cols)}  character")
+print(f"{'---':>6}  {'  '.join('------' for c in cols)}  -----------")
+for pid in pids:
+    r = check_pid(pid)
+    if r is None:
+        print(f"{pid:>6}  <dead>")
+        continue
+    name = get_window_title(pid)
+    row = "  ".join(f"{r[c]:>6}" for c in cols)
+    print(f"{pid:>6}  {row}  {name}")
+
+print()
+print("Legend: . = unpatched/original  P = patched (NOP/byte change)")
+print("        X = different (runtime-allocated thunk, e.g. v4/v5 -> custom code page)")