DISCLAIMER: These notes are from the defunct k8 project which precedes SquirrelJME. The notes for SquirrelJME start on 2016/02/26! The k8 project was effectively a Java SE 8 operating system and as such all of the notes are in the context of that scope. That project is no longer my goal as SquirrelJME is the spiritual successor to it.
It is snowing.
The tricky part of ELF is representing the potentially very dynamic program headers and section headers which may change interpretation if the ELF is modified. So I suppose instead I should have adapters which are used by the capacity where then they perform no actual storage, but only reading. Then this way the ELF can be modified without requiring some magic. However, modification of ELF files will rely on many bytes being moved within the file to make room for things (if the stuff being added is in the center). Since pretty much everything in the ELF usually appears in order. For Foobarniux this file order will be important because the ELF will be memory mapped and then directly executed. One key thing however is how sections are pretty much always mapped to program headers. In retrospect, instead of modifying an existing ELF I can always have an export which writes the actual changes to a given DataAccessor (which is not itself, since that would corrupt the input while writing to the output unless a separate image is created and then once it has been written it is placed over it).
Well, actually thinking about it, the program and section stuff does not have to appear in order in the file for Foobarniux to work. The only thing it has to know about is where methods and reference indices are. These would be pointers from the base of the ELF.
Another alternative is to just have ELFBinary be read only, and then have a ELF writer of sorts.
Or I could go for a very plain binary format, one which is essentially just an index of contents (so it would be like a ZIP file). Would seem a bit strange but I could have executable classes and such be stored in ZIP files with all of their code and reference tables. Using a ZIP would actually be rather easy to do. The only problem would be finding the end of the central index, but the size of the executable would be known. ZIP seems like a cop out but it does work and for what I need it can be rather simple (just code blobs).
I can still keep my existing ELF library code later because I will need it to load the kernel and such for bootstraps. Also using ZIP files means I do not need to perform section magic and I can have resources that can be used by the kernel (manifests, resources, images, etc.).
On the other hand, ZIP may be a bit too complex. All I need is a simple format which can store code and point to it. KBF is rather complex as it has multiple depth usage of classes and such. What I mean is that is required lots and lots of structures for storing data. However, this alternative format I can create can just be a flat formatted file which can store the desired information as needed. I can have it be rather relative. I can have a start of class file, followed by method code (as needed), any fields or annotations in it. Then end it with an end of class. Then having a simple table of contents format will make it simple without requiring potential massive work needing to handle sub-tables and such.
The main consideration is storage of the global constant pool, reference table, and the string table.
This information can be stored at the start which is then followed by the class data and then its code areas and such.
Lots and lots of snow. Also the radar shows mesocyclones in the middle of the large light blue areaas. I have not seen that before. The snow passing where I am right now is about 35dBZ.
I must concentrate and write this code.
IndexedSetStrings class can handle situations where constants and
references use strings.
It is extremely windy outside, cannot see much at all. I suppose this makes it a blizzard.
I suppose for the KBF, it will generally be just a large set of entries in a large table. That would keep things rather simple since most of the data would be shared between tables.