on windows: if the term is resized when ReadString is being called and no one is reading form ws, we get a panic: send on closed channel.
It could make sense to poll getconsolescreenbufferinfo calls instead of this:
something started from the sigwinch() func
on unix: same story, sigwinch was listened upon by default but if the
signals (chan sends) were not handled, this could cause a crash
fix#7434
* removed packer.Cache and references since packer.Cache is never used except in the download step. The download step now uses the new func packer.CachePath(targetPath) for this, the behavior is the same.
* removed download code from packer that was reimplemented into the go-getter library: progress bar, http download restart, checksuming from file, skip already downloaded files, symlinking, make a download cancellable by context.
* on windows if packer is running without symlinking rights and we are getting a local file, the file will be copied instead to avoid errors.
* added unit tests for step_download that are now CI tested on windows, mac & linux.
* files are now downloaded under cache dir `sha1(filename + "?checksum=" + checksum) + file_extension`
* since the output dir is based on the source url and the checksum, when the checksum fails, the file is auto deleted.
* a download file is protected and locked by a file lock,
* updated docs
* updated go modules and vendors
Megan Marsh
Adrien Delorme
유성덕
Chris Bednarski