IOS LLE: IPC trace prints filesystem IOCTL paths (StarletOS phase 11 M1e)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

Source/Core/Core/HW/WII_IPC.cpp

@@ -3,6 +3,7 @@
 
 #include "Core/HW/WII_IPC.h"
 
+#include <algorithm>
 #include <cstdlib>
 #include <string>
 
@@ -148,10 +149,11 @@ void WiiIPC::Shutdown()
 
 namespace
 {
-// StarletOS phase 11 (proposal L2): with DOLPHIN_IPC_TRACE=1 while the original IOS runs on the
-// emulated Starlet, each IPC request Broadway posts (X1) and each reply Starlet posts (Y1) is
-// logged with its metadata only: the command, the descriptor and the five argument words (an
-// OPEN's path), then the reply's result. Buffer contents are never read.
+// StarletOS phase 11 (proposal L2): with DOLPHIN_IPC_TRACE=1 while the emulated Starlet runs
+// (the original IOS or a bootstrap ELF), each IPC request Broadway posts (X1) and each reply
+// Starlet posts (Y1) is logged with its metadata only: the command, the descriptor and the five
+// argument words (an OPEN's path), then the reply's result. Proposal M1e adds the paths of the
+// filesystem IOCTLs. No other buffer content is read.
 bool IPCTraceEnabled()
 {
   static const bool enabled = [] {
@@ -161,6 +163,45 @@ bool IPCTraceEnabled()
   return enabled;
 }
 
+// A NUL-terminated absolute path of printable bytes in a 64-byte field, or "" otherwise.
+std::string TracePath(Memory::MemoryManager& memory, u32 address)
+{
+  if (memory.GetPointerForRange(address, 64) == nullptr)
+    return {};
+  const std::string path = memory.GetString(address, 64);
+  if (path.empty() || path.size() >= 64 || path[0] != '/' ||
+      !std::ranges::all_of(path, [](char c) { return c >= 0x20 && c < 0x7f; }))
+    return {};
+  return path;
+}
+
+// The paths a filesystem request names, by its input shape: a 64-byte path (DELETE, GET_ATTR),
+// a 76-byte attribute record with the path at +6 (CREATE_DIR, CREATE_FILE, SET_ATTR), two
+// 64-byte paths (RENAME), or an IOCTLV whose first input vector is a 64-byte path (READ_DIR,
+// GET_USAGE). " F -" when the field holds no valid path.
+std::string TraceFilesystemPaths(Memory::MemoryManager& memory, u32 command, const u32* arg)
+{
+  const auto field = [&memory](u32 address) {
+    const std::string path = TracePath(memory, address);
+    return path.empty() ? std::string("-") : path;
+  };
+  if (command == 6)
+  {
+    if (arg[2] == 0x40)
+      return " F " + field(arg[1]);
+    if (arg[2] == 0x4c)
+      return " F " + field(arg[1] + 6);
+    if (arg[2] == 0x80)
+      return " F " + field(arg[1]) + " > " + field(arg[1] + 0x40);
+  }
+  else if (command == 7 && arg[1] != 0 && memory.GetPointerForRange(arg[3], 8) != nullptr &&
+           memory.Read_U32(arg[3] + 4) == 0x40)
+  {
+    return " F " + field(memory.Read_U32(arg[3]));
+  }
+  return {};
+}
+
 void TraceIPCRequest(Core::System& system, u32 address)
 {
   auto& memory = system.GetMemory();
@@ -177,6 +218,8 @@ void TraceIPCRequest(Core::System& system, u32 address)
   std::string path;
   if (command == 1 && memory.GetPointerForRange(arg[0], 64) != nullptr)
     path = " P " + memory.GetString(arg[0], 64);
+  else
+    path = TraceFilesystemPaths(memory, command, arg);
   NOTICE_LOG_FMT(WII_IPC, "IPCTRACE RQ {:08x} C {} FD {} A {:08x} {:08x} {:08x} {:08x} {:08x}{}",
                  address, command, static_cast<s32>(fd), arg[0], arg[1], arg[2], arg[3], arg[4],
                  path);

docs/StarletOS_Checkpoint.json

@@ -48,8 +48,8 @@
     },
     {
       "path": "Source/Core/Core/HW/WII_IPC.cpp",
-      "sha256": "e216d272f7653b4650481a3335989a86550eee3d90aa7e6c7f06bb1ce87822e1",
-      "bytes": 21443
+      "sha256": "c3faf948533d494243caa229730dac8a8161144647aad22d219f1b4c9f727030",
+      "bytes": 23116
     },
     {
       "path": "Source/Core/Core/IOS/Starlet/ARMCore.cpp",
@@ -144,6 +144,13 @@
         "Source/Core/Core/IOS/Starlet/StarletMemory.cpp",
         "Source/Core/Core/IOS/Starlet/StarletMemory.h"
       ]
+    },
+    {
+      "recordedAt": "2026-10-06",
+      "purpose": "StarletOS Phase 11 proposal M1e: the IPC trace also prints the paths named by filesystem IOCTLs (64-byte path, 76-byte record at +6, rename pair, first IOCTLV vector of 64 bytes); paths only",
+      "files": [
+        "Source/Core/Core/HW/WII_IPC.cpp"
+      ]
     }
   ]
 }

docs/StarletOS_Handoff.md

@@ -159,3 +159,16 @@ with Revolution instead of the original IOS, to see where Broadway stops.
 
 Next: the companion's M1b (smoke test with the variable, no window) and M1c
 (the user launches the Mii Channel under Revolution in the X11 window).
+
+## Filesystem paths in the IPC trace — 2026-10-06
+
+Companion proposal M1e (approved): under Revolution in the window the System
+Menu's save before a launch got -106 on its second CREATE_DIR, and no trace
+had the path. `IPCTRACE RQ` lines now end with ` F <path>` for IOCTLs whose
+input is a 64-byte path (DELETE, GET_ATTR), a 76-byte attribute record (path
+at +6: CREATE_DIR, CREATE_FILE, SET_ATTR) or two paths (` F a > b`, RENAME),
+and for IOCTLVs whose first input vector is 64 bytes (READ_DIR, GET_USAGE);
+` F -` when that field holds no valid path. Read from memory when X1 is
+rung, like the OPEN path; nothing else of the buffers. Checked headless under
+Revolution: `/shared2/test2`, `/title/00000001/00000002/data/cache.dat`, the
+GET_USAGE directories. 95 Starlet tests passed.