Fix Issue #997

[stephengtuggy]

Code Changes:

• Have the PR Validation Tests been run? See https://github.com/vegastrike/Vega-Strike-Engine-Source/wiki/Pull-Request-Validation

Issues:

• Fixes Crash loading saved games on Windows due to "root" values in the ship JSON like "V:\Assets-Production" instead of "V:\\Assets-Production" #997

Purpose:

• What is this pull request trying to do? Fix a bug that affects saving and loading unit files on Windows
• What release is this for? 0.10.x
• Is there a project or milestone we should apply this to? 0.10.x

[evertvorster]

You know what would be great? If the PR's or engine have some sort of description of which branch of Assets they need to be tested against.
Unfortunately I don't have a Windows environment, so this is about the only positive contribution I can make at this point.

[kheckwrecker]

Having a problem with game crashing after launching new campaign. Here's the debugger output:
Exception thrown at 0x00007FFDEABEB699 in vegastrike-engine.exe: Microsoft C++ exception: boost::wrapexceptboost::system::system_error at memory location 0x00000006C056C2E0.
Error parsing JSON in UnitJSONFactory::ParseJSON(): syntax error [boost.json:1 at D:\VS_Master_Test\Vega-Strike-Engine-Source\build\VS2022Win64-pie-disabled-release\vcpkg_installed\vcpkg\blds\boost-json\src\ost-1.84.0-6591c5c930.clean\include\boost/json/basic_parser_impl.hpp:1270:19 in function 'parse_escaped']
The thread 10244 has exited with code 0 (0x0).
The thread 'alsoft-mixer' (9648) has exited with code 0 (0x0).
The thread 11380 has exited with code 0 (0x0).
The thread 11572 has exited with code 42 (0x2a).
The thread 9248 has exited with code 42 (0x2a).
The thread 11648 has exited with code 42 (0x2a).
The thread 12080 has exited with code 42 (0x2a).
The thread 2316 has exited with code 42 (0x2a).
The thread 12104 has exited with code 42 (0x2a).
The thread 9356 has exited with code 42 (0x2a).
The thread 11808 has exited with code 42 (0x2a).
The thread 12272 has exited with code 42 (0x2a).
The thread 9444 has exited with code 42 (0x2a).
The thread 11564 has exited with code 42 (0x2a).
The thread 10836 has exited with code 42 (0x2a).
The program '[12228] vegastrike-engine.exe' has exited with code 42 (0x2a).

Is this the same problem?

[stephengtuggy]

@kheckwrecker yeah, I'm pretty sure that's the same problem that this PR addresses.

Or one of them, anyway.

[kheckwrecker]

Ok. I'll try pulling this patch and see if it works.

[kheckwrecker]

GitHub is having trouble with the pull request. Something about not find your work? Anyway, I'll just wait until it's approved and merged then try again.

[kheckwrecker]

I pulled this patch and re-compiled, but it's still crashing with the same error. It's entirely possible that I'm screwing up the pull and merge, so I'll wait and try again after this patch is officially merged with master. If the problem still occurs after that, I'll create a new issue report.

[royfalk]

Where is the fix for root? I assumed the offending line would be
unit_attributes["root"] = file.GetRoot();
but you didn't actually change it.

[royfalk]

My code (deficiencies and all) assumed the following:

[
   {"a": "1", "b": 2},
   {"a": "1", "b": 2},
   {"a": "1", "b": 2},
   ...
]

However, this looks like it supports other file formats such as {"a": "1", "b": 2} without an array. Why would we do this?

[stephengtuggy]

Because that's how the Boost JSON serialization function constructs it. So when we go to load the file, we need to support either format -- with or without an array at the top level.

[stephengtuggy]

To clarify further: Roy, your code saved an array with a single object element inside of it:

[
    {
        ...
    }
]

My code simply removes the root array:

{
    ...
}

[royfalk]

Unfortunately, we actually want the array. Right now the game saves each ship in its own file. There's no reason to do this. We just need to figure the whole player_ship issue. Either, replace it with player_ship_1...2...3 or player_ship_<random 6 alphanumeric> or something like that and check for prefix.

This would also solve the issue of not supporting a fleet containing two ships of the same type.

[stephengtuggy]

I see.

[stephengtuggy]

Where is the fix for root? I assumed the offending line would be unit_attributes["root"] = file.GetRoot(); but you didn't actually change it.

I thought it would be too, but as it turned out, that was not the problem.