readstat-iconv-sys

Windows-only FFI bindings to win-iconv for character encoding conversion.

win-iconv is an iconv implementation backed by the Win32 conversion APIs (MultiByteToWideChar / WideCharToMultiByte). It is the same iconv implementation that R for Windows bundles, so ReadStat-over-win-iconv is well proven in production.

The build.rs script compiles win-iconv from the vendored vendor/win-iconv/ git submodule using the cc crate when the target OS is Windows. On non-Windows targets the build script is a no-op.

The links = "iconv" key in Cargo.toml allows readstat-sys to discover the include path via the DEP_ICONV_INCLUDE environment variable.

Encoding coverage

win-iconv maps encoding names to Windows codepages. All mainstream sas7bdat encodings are covered: WINDOWS-1250..1258, ISO-8859-1..15, UTF-8/16/32, US-ASCII, the common DOS codepages (CP437, CP850, …), CP932 (Shift-JIS), CP936 (GBK), CP949, CP950, GB18030, BIG5, EUC-JP, ISO-2022-JP, KOI8-R/U and the common Mac codepages. A handful of tail encodings that GNU libiconv implements in software have no Win32 codepage equivalent (e.g. EUC-TW, ISO-2022-KR/CN); files in those encodings fail cleanly at iconv_open with READSTAT_ERROR_UNSUPPORTED_CHARSET rather than being read incorrectly.

License

This crate is MIT. The vendored win-iconv is placed in the public domain (see vendor/win-iconv/readme.txt and the header of vendor/win-iconv/win_iconv.c), so statically linking it into Windows builds imposes no copyleft obligations — unlike GNU libiconv (LGPL-2.1-or-later), which this crate vendored in v0.3.x and earlier. On non-Windows platforms the build script is a no-op and the crate links nothing.