removed memset calls I don't think filling the structure pointers wasted time more than anything
replaced some unnecessary allocation with stack-based arrays
replaced strcmp with a for loop so it's slightly faster because ends slightly sooner
removed strlen calls in fons__fopen (based on stb_image, it seems these aren't required)
note: if this causes some problems, it'd still be better to replace it with a for loop that iterates through both strings so it's not doing two separate loops per string.
made it so if end == NULL it just iterates the string until it reaches '0' instead of setting end to the end. This makes it so it only loops through the string once. (Again, because strlen is doing a loop through the string).
removed memset calls I don't think filling the structure pointers wasted time more than anything
replaced some unnecessary allocation with stack-based arrays
replaced strcmp with a for loop so it's slightly faster because ends slightly sooner
removed strlen calls in fons__fopen (based on stb_image, it seems these aren't required)
note: if this causes some problems, it'd still be better to replace it with a for loop that iterates through both strings so it's not doing two separate loops per string.