bootloader: clean up endianess conversion #5457
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The conversion of multi-byte integer fields in COOKIE and TOC structures is a data (de)serialization detail, and as such should be performed only once, after the data is read; as opposed to on-the-fly endianess conversions on every field access, which are scattered throughout the codebase.
On Windows, use built-in byte-swap macros instead of ntohl(), which is available from winsock2 library. Using the latter requires the bootloader to be linked against the winsock2 library, which may have other unintended consequences. On all other platforms, continue using ntohl() for now, but hide it behind the pyi_be32toh() macro.
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bwoodsend
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Jan 28, 2021
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This PR places the endianess conversion for multi-byte integer fields in COOKIE and TOC structures in a single place, i.e., after the data is read from the file (as opposed to performing it on every field access). The main motivation is to simplify the eventual transition from 32-bit integers to 64-bit ones to increase maximum archive file size.
On Windows, replace the use of
ntohl()fromws2_32library with compiler-provided byte-swap functions. This allows us to drop otherwise unneccessary dependency onws2_32in bootloader executables.