Unverified Commit 233205c4 authored by Mateusz Kowalczyk's avatar Mateusz Kowalczyk
Browse files

rustBuildCrate: properly handle cargo env pragmas with spaces 

There are two problems: first that we end up splitting on spaces in the
loop. Even when that is fixed, we still would split on spaces in the
`export` inside the loop. We need to guard against both.

Fixes #199298

Confirmed that it fixes the case mentioned in the ticket:

```console
[nix-develop]$ $(nix-build -I nixpkgs=/home/shana/programming/nixpkgs Cargo.nix -A rootCrate.build  --no-out-link)/bin/nix-rustc-env-escape-repro
Expecting three words, got: first second third
```

I think this is going to cause a rebuild of every Rust package even if
they were unaffected, not much we can do here.
parent 1f1ed641

pkgs/build-support/rust/build-rust-crate/configure-crate.nix

+13 −1
Original line number Diff line number Diff line
@@ -189,9 +189,21 @@ in '' 
     EXTRA_LINK=$(sed -n "s/^cargo:rustc-link-lib=\(.*\)/\1/p" target/build/${crateName}.opt | tr '\n' ' ')

     EXTRA_LINK_SEARCH=$(sed -n "s/^cargo:rustc-link-search=\(.*\)/\1/p" target/build/${crateName}.opt | tr '\n' ' ' | sort -u)



     # We want to read part of every line that has cargo:rustc-env= prefix and

     # export it as environment variables. This turns out tricky if the lines

     # have spaces: we can't wrap the command in double quotes as that captures

     # all the lines in single output. We can't use while read loop because

     # exporting from inside of it doesn't make it to the outside scope. We

     # can't use xargs as export is a built-in and does not work from it. As a

     # last resort then, we change the IFS so that the for loop does not split

     # on spaces and reset it after we are done. See ticket #199298.

     #

     _OLDIFS="$IFS"

     IFS=$'\n'

     for env in $(sed -n "s/^cargo:rustc-env=\(.*\)/\1/p" target/build/${crateName}.opt); do

       export $env

       export "$env"

     done

     IFS="$_OLDIFS"



     CRATENAME=$(echo ${crateName} | sed -e "s/\(.*\)-sys$/\U\1/" -e "s/-/_/g")

     grep -P "^cargo:(?!(rustc-|warning=|rerun-if-changed=|rerun-if-env-changed))" target/build/${crateName}.opt \