Mini string library for REs

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RE Developer
Posts: 483
Joined: 21 Apr 2016
Location: Las Vegas

Post 02 Feb 2021

If you follow the internal RE dev forum, you probably saw that I was asking about how to do string manipulation mostly to dynamically build property name. The answer was, there is no such thing...

So I just spent over a week or so building a mini string library for REs and I have integrated it in my re-common mini framework. It is mind boggling that such a concept is not part of the SDK, especially since it is such a basic need for a developer. It is like if you were building a house and the first thing you have to do is build your own hammer...

The main API implemented is fmt::printf which implements a very simplified version of the C api printf (only handles %d and %s with no other variants allowed at the moment).

With this basic API, I built a jbox namespace with convenient calls to replace JBox_GetMotherboardObjectRef and JBox_MakePropertyRef.


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// from VerySimpleSampler.cpp (example in RE SDK)

// code with new api
// N = 4
for(int i = 0; i < N; i++)
   fSampleNativeObjectRefs[i] = jbox::get_property_ref(fMotherBoardCustomPropertiesRef, "sample_sound_native_object%d", i);
   fSampleZoneObjectRefs[i] = jbox::get_object_ref("/user_samples/%d", i);

// vs original code
fSampleNativeObjectRefs[0] = JBox_MakePropertyRef(fMotherBoardCustomPropertiesRef, "sample_sound_native_object0");
fSampleNativeObjectRefs[1] = JBox_MakePropertyRef(fMotherBoardCustomPropertiesRef, "sample_sound_native_object1");
fSampleNativeObjectRefs[2] = JBox_MakePropertyRef(fMotherBoardCustomPropertiesRef, "sample_sound_native_object2");
fSampleNativeObjectRefs[3] = JBox_MakePropertyRef(fMotherBoardCustomPropertiesRef, "sample_sound_native_object3");
fSampleZoneObjectRefs[0] = JBox_GetMotherboardObjectRef("/user_samples/0");
fSampleZoneObjectRefs[1] = JBox_GetMotherboardObjectRef("/user_samples/1");
fSampleZoneObjectRefs[2] = JBox_GetMotherboardObjectRef("/user_samples/2");
fSampleZoneObjectRefs[3] = JBox_GetMotherboardObjectRef("/user_samples/3");

I also implemented a StaticString class which encapsulates a C-Style null terminated char array (note that in debug mode it uses std::array so it is safer, and in release mode it uses char[] which is faster) and defined the 3 main types as such:

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using ObjectPath = StaticString<kJBox_MaxObjectNameLen + 1>;
using PropertyName = StaticString<kJBox_MaxPropertyNameLen + 1>;
using PropertyPath = StaticString<kMaxPropertyPathLen + 1>;
Since this class can be implicitly cast to a "char const *" it can be used wherever a "char const *" is needed...

Code: Select all

JBox_GetMotherboardObjectRef(ObjectPath::printf("/user_samples/%d", 3));

// note that this is exactly what jbox::get_object_ref does ;)
If you want to use in your own project you can obviously depend on re-common. If you only want the library you can copy the files fmt.h, jbox.h/jbox.cpp and StaticString.h into your own project. They are not dependent on the rest of re-common. If you only care about fmt::printf then you can simply copy fmt.h only.

Here is the commit that shows the simplification that it brings to re-cva-7 (which had to initialize 256 properties just for the display by hand...)


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RE Developer
Posts: 50
Joined: 21 Jan 2015

Post 02 Feb 2021

Nice work. I had to do a similar thing back in 2012 for AutoTheory which had lots of enumerated property names.

If I'd known you were going to write your own I would have just given you my library though - sorry!

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Posts: 4202
Joined: 09 Dec 2016

Post 02 Feb 2021

I guess this is the beauty of allowing open discussion of the sdk.

And thanks for autotheory I got it straight away when it came out and it was awesome.

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