Merge autoPatchelfHook improvements (#47222)

This includes the initialy commit was done by @Mic92 plus a few fixes
from my side. So essentially this avoids patching statically linked
executables and also speeds up searching for ELF files altogether.

I've tested this by comparing the outputs of all the derivations which
make use of this hook using the following Nix expression:

  let
    getPackagesForRev = rev: with import (builtins.fetchGit {
      url = ./.;
      inherit rev;
    }) { config.allowUnfree = true; }; [
      cups-kyodialog3 elasticsearch franz gurobi javacard-devkit
      masterpdfeditor maxx oracle-instantclient powershell reaper
      teamviewer unixODBCDrivers.msodbcsql17 virtlyst wavebox zoom-us
    ];

    pkgs = import <nixpkgs> {};
    baseRev = "ef764eb0d8314b81a012dae04642b4766199956d";

  in pkgs.runCommand "diff-contents" {
    chset = pkgs.lib.zipListsWith (old: new: pkgs.runCommand "diff" {
      inherit old new;
      nativeBuildInputs = [ pkgs.nukeReferences ];
    } ''
      mkdir -p "''${NIX_STORE#/}"
      cp --no-preserve=all -r "$old" "''${NIX_STORE#/}"
      cp --no-preserve=all -r "$new" "''${NIX_STORE#/}"
      find "''${old#/}" "''${new#/}" \
        \( -type f -exec nuke-refs {} + \) -o \( -type l -delete \)
      mkdir "$out"
      echo "$old" > "$out/old-path"
      echo "$new" > "$out/new-path"
      diff -Nur "''${old#/}" "''${new#/}" > "$out/diff" || :
    '') (getPackagesForRev baseRev) (getPackagesForRev "");
  } ''
    err=0
    for c in $chset; do
      if [ -s "$c/diff" ]; then
        echo "$(< "$c/old-path") -> $(< "$c/new-path")" \
             "differs, report: $c/diff" >&2
        err=1
      fi
    done
    [ $err -eq 0 ] && touch "$out"
  ''

With these changes there is only one derivation which has altered
contents, which is "franz". However the reason why it has differing
contents is not directly because of the autoPatchelfHook changes, but
because the "env-vars" file from the builder is in
"$out/opt/franz/env-vars" (Cc: @gnidorah) and we now have different
contents for NIX_CFLAGS_COMPILE and other environment variables.

I also tested this against a random static binary and the hook no longer
tries to patch it.

Merges: #47222

1 files changed, 9 insertions, 18 deletions

diff --git a/pkgs/build-support/setup-hooks/auto-patchelf.sh b/pkgs/build-support/setup-hooks/auto-patchelf.sh
index 32fdb1000e27..7c165627f72e 100644
--- a/pkgs/build-support/setup-hooks/auto-patchelf.sh
+++ b/pkgs/build-support/setup-hooks/auto-patchelf.sh
@@ -7,21 +7,7 @@ gatherLibraries() {
 addEnvHooks "$targetOffset" gatherLibraries
 
 isExecutable() {
-    [ "$(file -b -N --mime-type "$1")" = application/x-executable ]
-}
-
-findElfs() {
-    find "$1" -type f -exec "$SHELL" -c '
-        while [ -n "$1" ]; do
-            mimeType="$(file -b -N --mime-type "$1")"
-            if [ "$mimeType" = application/x-executable \
-              -o "$mimeType" = application/x-pie-executable \
-              -o "$mimeType" = application/x-sharedlib ]; then
-                echo "$1"
-            fi
-            shift
-        done
-    ' -- {} +
+    readelf -h "$1" 2> /dev/null | grep -q '^ *Type: *EXEC\>'
 }
 
 # We cache dependencies so that we don't need to search through all of them on
@@ -167,9 +153,14 @@ autoPatchelf() {
     # findDependency outside of this, the dependency cache needs to be rebuilt
     # from scratch, so keep this in mind if you want to run findDependency
     # outside of this function.
-    findElfs "$prefix" | while read -r elffile; do
-        autoPatchelfFile "$elffile"
-    done
+    while IFS= read -r -d $'\0' file; do
+      isELF "$file" || continue
+      if isExecutable "$file"; then
+          # Skip if the executable is statically linked.
+          readelf -l "$file" | grep -q "^ *INTERP\\>" || continue
+      fi
+      autoPatchelfFile "$file"
+    done < <(find "$prefix" -type f -print0)
 }
 
 # XXX: This should ultimately use fixupOutputHooks but we currently don't have