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Android: `SDL_GetPathInfo` doesn't default to "assets" like other file functions.
The following line will return false, to suggest the file doesn't exist:
SDL_GetPathInfo("example.text", 0);
However, the following line will work, because the file does exist:
SDL_LoadFile("example.text", 0);
The file is in \app\src\main\assets, which seems to be the default for many file operations, but not SDL_GetPathInfo, maybe? Is it unreasonable to assume it should default to assets without a full path specified?
Okay, so this happens because SDL_LoadFile is backed by SDL_IOFromFile, which has a ton of Android-specific code.
But SDL_GetPathInfo() is just calling POSIX functions on Android.
So fixing this probably means rolling a bunch of Android code to use AAssetManager in some cases, and POSIX in others.
It's doable, but it's not gonna make it for 3.2.16.
That's fair. It's not a deal breaker because there are plenty of ways around it.
Should we put a note in so it doesn't trip anyone up?
Or, how easy would it be to just insert the current path if a relative path is detected?
SDL_GetPathInfo returns with false and error "Can't stat: No such file or directory" for files selected using SDL_ShowOpenFileDialog as well (and can be loaded successfully using SDL_LoadFile), so it seems that is not working in general.
Okay, this is pushed to main: 515433aa8a8fdeb0be4d0e2e1ee733ad16fc7d6e
It works like SDL_IOStream: it'll try real filesystem accesses, and if that doesn't work out, it'll try the AssetManager. Assets don't have file times, so they always come back as zero in SDL_GetPathInfo() in this case, but I assume most things just want file size and type anyhow.
If it's possible, can you make sure this works for your app before I cherry-pick it over to release-3.2.x?
Only now looking at this, apologise for delay. This still isn't behaving as expected. SDL_GetPathInfo("anything", null) is returning true for everything.
Stepping through the code in SDL_android.c's Android_JNI_GetAssetPathInfo. In the following code, AAssetManager_openDir returns a valid AAssetDir object (not null) even if path isn't a path:
// this is sort of messy, but there isn't a stat()-like interface to the Assets.
AAssetDir *adir = AAssetManager_openDir(asset_manager, path);
if (adir) { // it's a directory!
AAssetDir_close(adir);
info->type = SDL_PATHTYPE_DIRECTORY;
info->size = 0;
return true;
}
Sure enough, it never returns NULL:
https://android.googlesource.com/platform/frameworks/base/+/master/native/android/asset_manager.cpp#94
Okay, so it looks like AAssetManager_open() will return NULL, so we can flip this to look for files first, and directories second, and then check if the directory is empty (AAssetDir_getNextFileName returns NULL)...if empty, we assume the directory doesn't exist.
This isn't perfect, but it's probably good enough...?
(Notably: this never returns NULL because asset dirs are a union of multiple .zip files that might each have the same directory.)
Sorry, you seem to get all the nice bug-fixes 🤣. Yes, that's done the trick, thank you. Tested exists functionality in assets, and full paths. Shame about empty directories, but looks like the best it's going to be.