Don't try to grow the buffer more than allowed by the system

[targos]

• refactor: move endianness check to separate file
• fix: don't try to grow the buffer more than allowed by the system

Closes: image-js/fast-png#42

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (9a39938) to head (0d1486a).

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #75   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         3    +1     
  Lines          337       378   +41     
  Branches        75        84    +9     
=========================================
+ Hits           337       378   +41     

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[targos]

I don't know how to reliably detect what is the maximum size for a typed array. Since Node.js 22, there is no arbitrary limit in V8.
On macOS, what I pushed here works because the memory is not really allocated (it's in the virtual space), but on Linux it's real and makes the process crash when we try too high.

@lpatiny Any idea?

[lpatiny]

Maybe using on node

> require('v8').getHeapStatistics()
{
  total_heap_size: 543752192,
  total_heap_size_executable: 524288,
  total_physical_size: 543752192,
  total_available_size: 3804536944,
  used_heap_size: 541746816,
  heap_size_limit: 4345298944,
  malloced_memory: 278632,
  peak_malloced_memory: 874496,
  does_zap_garbage: 0,
  number_of_native_contexts: 1,
  number_of_detached_contexts: 0,
  total_global_handles_size: 12800,
  used_global_handles_size: 4512,
  external_memory: 2312309
}
> var b=new Array(2**26).fill(0).map(Math.random)
undefined
> require('v8').getHeapStatistics()
{
  total_heap_size: 3260137472,
  total_heap_size_executable: 524288,
  total_physical_size: 3260137472,
  total_available_size: 1102417256,
  used_heap_size: 3225912760,
  heap_size_limit: 4345298944,
  malloced_memory: 278632,
  peak_malloced_memory: 874496,
  does_zap_garbage: 0,
  number_of_native_contexts: 1,
  number_of_detached_contexts: 0,
  total_global_handles_size: 12800,
  used_global_handles_size: 4608,
  external_memory: 2312293
}

and in the browser

performance.memory.jsHeapSizeLimit
performance.memory.totalJSHeapSize

Actually this is something very important also in nmr-load-save so if we have a package that is node / browser compatible it would be very usefull.

[targos]

I'm not sure the js heap size is relevant. ArrayBuffer data are notably not counted in it.

[targos]

And in browsers, the typed array size limit is unrelated to the memory limit. It's arbitrarily chosen by the browser.