mirror of
https://github.com/tailscale/tailscale.git
synced 2025-12-23 18:21:28 +01:00
dbaf0b0472
Raw Linux consoles support UTF-8, but we cannot assume that all UTF-8 characters are available. The default Fixed and Terminus fonts don’t contain half-block characters (`▀` and `▄`), but do contain the full-block character (`█`). Sometimes, Linux doesn’t have a framebuffer, so it falls back to VGA. When this happens, the full-block character could be anywhere in extended ASCII block, because we don’t know which code page is active. This PR introduces `--qr-format=auto` which tries to heuristically detect when Tailscale is printing to a raw Linux console, whether UTF-8 is enabled, and which block characters have been mapped in the console font. If Unicode characters are unavailable, the new `--qr-format=ascii` formatter uses `#` characters instead of full-block characters. Fixes #12935 Signed-off-by: Simon Law <sfllaw@tailscale.com>