Merge pull request NixOS#124556 from bergkvist/bergkvist/make-c-wrapper

Generate tiny compiled binary for wrapping executables

doc/stdenv/stdenv.chapter.md

@@ -796,7 +796,7 @@ The standard environment provides a number of useful functions.
 
 ### `makeWrapper` \<executable\> \<wrapperfile\> \<args\> {#fun-makeWrapper}
 
-Constructs a wrapper for a program with various possible arguments. For example:
+Constructs a wrapper for a program with various possible arguments. It is defined as part of 2 setup-hooks named `makeWrapper` and `makeBinaryWrapper` that implement the same bash functions. Hence, to use it you have to add `makeWrapper` to your `nativeBuildInputs`. Here's an example usage:
 
 ```bash
 # adds `FOOBAR=baz` to `$out/bin/foo`’s environment
@@ -808,9 +808,11 @@ makeWrapper $out/bin/foo $wrapperfile --set FOOBAR baz
 makeWrapper $out/bin/foo $wrapperfile --prefix PATH : ${lib.makeBinPath [ hello git ]}
 ```
 
-There’s many more kinds of arguments, they are documented in `nixpkgs/pkgs/build-support/setup-hooks/make-wrapper.sh`.
+There’s many more kinds of arguments, they are documented in `nixpkgs/pkgs/build-support/setup-hooks/make-wrapper.sh` for the `makeWrapper` implementation and in `nixpkgs/pkgs/build-support/setup-hooks/make-binary-wrapper.sh` for the `makeBinaryWrapper` implementation.
 
-`wrapProgram` is a convenience function you probably want to use most of the time.
+`wrapProgram` is a convenience function you probably want to use most of the time, implemented by both `makeWrapper` and `makeBinaryWrapper`.
+
+Using the `makeBinaryWrapper` implementation is usually preferred, as it creates a tiny _compiled_ wrapper executable, that can be used as a shebang interpreter. This is needed mostly on Darwin, where shebangs cannot point to scripts, [due to a limitation with the `execve`-syscall](https://stackoverflow.com/questions/67100831/macos-shebang-with-absolute-path-not-working). Compiled wrappers generated by `makeBinaryWrapper` can be inspected with `less <path-to-wrapper>` - by scrolling past the binary data you should be able to see the shell command that generated the executable and there see the environment variables that were injected into the wrapper.
 
 ### `substitute` \<infile\> \<outfile\> \<subs\> {#fun-substitute}
 
@@ -885,9 +887,9 @@ someVar=$(stripHash $name)
 
 ### `wrapProgram` \<executable\> \<makeWrapperArgs\> {#fun-wrapProgram}
 
-Convenience function for `makeWrapper` that automatically creates a sane wrapper file. It takes all the same arguments as `makeWrapper`, except for `--argv0`.
+Convenience function for `makeWrapper` that replaces `<\executable\>` with a wrapper that executes the original program. It takes all the same arguments as `makeWrapper`, except for `--inherit-argv0` (used by the `makeBinaryWrapper` implementation) and `--argv0` (used by both `makeWrapper` and `makeBinaryWrapper` wrapper implementations).
 
-It cannot be applied multiple times, since it will overwrite the wrapper file.
+If you will apply it multiple times, it will overwrite the wrapper file and you will end up with double wrapping, which should be avoided.
 
 ## Package setup hooks {#ssec-setup-hooks}
 

maintainers/maintainer-list.nix

@@ -1414,6 +1414,12 @@
     githubId = 251106;
     name = "Daniel Bergey";
   };
+  bergkvist = {
+    email = "tobias@bergkv.ist";
+    github = "bergkvist";
+    githubId = 410028;
+    name = "Tobias Bergkvist";
+  };
   betaboon = {
     email = "betaboon@0x80.ninja";
     github = "betaboon";