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bugfix(ai): Fix AICommandParmsStorage::doXfer to transfer the command source #3156

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bugfix(ai): Fix AICommandParmsStorage::doXfer to transfer the command source #3156

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8 changes: 7 additions & 1 deletion Generals/Code/GameEngine/Source/GameLogic/AI/AIStates.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -126,7 +126,13 @@ void AICommandParmsStorage::reconstitute(AICommandParms& parms) const
void AICommandParmsStorage::doXfer(Xfer *xfer)
{
xfer->xferUser(&m_cmd, sizeof(m_cmd));
xfer->xferUser(&m_cmd, sizeof(m_cmdSource));
// TheSuperHackers @bugfix Transfer the command source instead of the command twice.
xfer->xferUser(&m_cmdSource, sizeof(m_cmdSource));
Comment on lines +129 to +130

@qodo-free-for-open-source-projects qodo-free-for-open-source-projects Bot Aug 15, 2026

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Action required

1. Invalid cmdsource from old saves 🐞 Bug ☼ Reliability

When loading a save created before this fix, the slot now read into m_cmdSource contains the old
duplicated m_cmd bytes, producing out-of-range CommandSourceType values. That invalid value is
later used unchecked (e.g., (1 << cmdSource) in weapon selection), which can cause undefined
behavior/crashes and incorrect command-source filtering.
Agent Prompt 
### Issue description
After this PR, `AICommandParmsStorage::doXfer` correctly transfers `m_cmdSource`, but **old saves written by the previous code** stored a duplicate of `m_cmd` in the second field. Loading those saves will therefore set `m_cmdSource` to an invalid `CommandSourceType` value.

This becomes dangerous because other code paths assume `CommandSourceType` is in-range and use it in bit operations (e.g., `1 << cmdSource`), which can become undefined behavior if `cmdSource` is large.

### Issue Context
- `CommandSourceType` has only a few valid values (`CMD_FROM_PLAYER`..`CMD_DEFAULT_SWITCH_WEAPON`, then `COMMAND_SOURCE_TYPE_COUNT`).
- `AICommandType` has many values and can exceed the bit-width safe range for shifting.
- `AICommandParmsStorage::doXfer` currently does not validate `m_cmdSource` after loading.

### Fix Focus Areas
- Add a post-load validation step in `AICommandParmsStorage::doXfer` to clamp/normalize `m_cmdSource` when `xfer->getXferMode() == XFER_LOAD`.
  - Example approach: after `xferUser(&m_cmdSource, ...)`, check `static_cast<Int>(m_cmdSource)` is within `[0, COMMAND_SOURCE_TYPE_COUNT)`; if not, set to a safe default (likely `CMD_FROM_AI`).
- Apply the same fix in both game variants.

Recommended code shape (illustrative):
```cpp
xfer->xferUser(&m_cmdSource, sizeof(m_cmdSource));
if (xfer->getXferMode() == XFER_LOAD) {
  const Int cs = static_cast<Int>(m_cmdSource);
  if (cs < 0 || cs >= COMMAND_SOURCE_TYPE_COUNT) {
    m_cmdSource = CMD_FROM_AI;
  }
}
```

### Fix Focus Areas (exact locations)
- Generals/Code/GameEngine/Source/GameLogic/AI/AIStates.cpp[126-133]
- GeneralsMD/Code/GameEngine/Source/GameLogic/AI/AIStates.cpp[129-136]

ⓘ Copy this prompt and use it to remediate the issue with your preferred AI generation tools

if (xfer->getXferMode() == XFER_LOAD && (m_cmdSource < CMD_FROM_PLAYER || m_cmdSource >= COMMAND_SOURCE_TYPE_COUNT))
{
// TheSuperHackers @info Saves from before this fix contain a copy of the command in the command source slot.
m_cmdSource = CMD_FROM_AI;
}
xfer->xferCoord3D(&m_pos);
xfer->xferObjectID(&m_obj);
xfer->xferObjectID(&m_otherObj);
Expand Down
8 changes: 7 additions & 1 deletion GeneralsMD/Code/GameEngine/Source/GameLogic/AI/AIStates.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -129,7 +129,13 @@ void AICommandParmsStorage::reconstitute(AICommandParms& parms) const
void AICommandParmsStorage::doXfer(Xfer *xfer)
{
xfer->xferUser(&m_cmd, sizeof(m_cmd));
xfer->xferUser(&m_cmd, sizeof(m_cmdSource));
// TheSuperHackers @bugfix Transfer the command source instead of the command twice.
xfer->xferUser(&m_cmdSource, sizeof(m_cmdSource));
if (xfer->getXferMode() == XFER_LOAD && (m_cmdSource < CMD_FROM_PLAYER || m_cmdSource >= COMMAND_SOURCE_TYPE_COUNT))
{
// TheSuperHackers @info Saves from before this fix contain a copy of the command in the command source slot.
m_cmdSource = CMD_FROM_AI;
}
xfer->xferCoord3D(&m_pos);
xfer->xferObjectID(&m_obj);
xfer->xferObjectID(&m_otherObj);
Expand Down
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