zig fetch: Erroneous `FileBusy` error if package tarball's paths are prefixed with `./`

[TUSF]

Zig Version

0.14.0

Steps to Reproduce and Observed Behavior

Discovered when trying to figure out why one could not run:

zig fetch https://github.com/microsoft/DirectXShaderCompiler/releases/download/v1.8.2407/linux_dxc_2024_07_31.x86_64.tar.gz

Is was returning the error:

error: unable to rename temporary directory '~/.cache/zig/tmp/53571228b81b7e97' into package cache directory '~/.cache/zig/p/N-V-__8AAH2XGgKqo-yDbpTxRrXI5AYuCxdb_Ni7QOWeQTVZ': FileBusy

So I thought to figure out what's wrong with the tarbal that Zig can't seem to handle. When running tar -vtf on the file, I noticed all of the file paths contain the ./ prefix. To make sure this was the case, I created a test package, and ran a local http server.

$ tar -czf archive.tar.gz test-package/
$ tar -vtf archive.tar.gz
drwxr-xr-x jeremia/jeremia   0 2025-03-08 18:37 test-package/
-rw-r--r-- jeremia/jeremia  16 2025-03-08 18:37 test-package/README.md
$ zig fetch http://localhost:8000/archive.tar.gz
N-V-__8AABAAAAAtCjsC7HRmOePNKF3sNsz72cJJcqmOKQ9z

$ tar -czf archive.tar.gz ./test-package/
$ tar -vtf archive.tar.gz
drwxr-xr-x jeremia/jeremia   0 2025-03-08 18:37 ./test-package/
-rw-r--r-- jeremia/jeremia  16 2025-03-08 18:37 ./test-package/README.md
$ zig fetch http://localhost:8000/archive.tar.gz
error: unable to rename temporary directory '/home/jeremia/.cache/zig/tmp/b320d5ba7b7de384' into package cache directory '/home/jeremia/.cache/zig/p/N-V-__8AABAAAABxCaA3CyssWe86Ow1EtjeUO7PNWcNonp79': FileBusy

Expected Behavior

For the tarball to be extracted and moved properly regardless of the "current directory" prefix.

[orvitpng]

Having the same issue on 0.14.

[gwenzek]

Thanks for detecting the bug with the prefix.

I tested the following fix on MacOS and it does seem to work. The .tar.gz is now correctly extracted and files moved to zig-cache/p/

https://github.com/ziglang/zig/compare/master...gwenzek:gw/fix_tasr?expand=1

[gwenzek]

Proposed fix: #24197