daemon: Run 'guix offload' directly.

* nix/scripts/offload.in: Remove.
* nix/local.mk (nodist_pkglibexec_SCRIPTS) [BUILD_DAEMON_OFFLOAD]:
Remove 'scripts/offload'.
* config-daemon.ac: Don't output 'nix/scripts/offload'.
* build-aux/pre-inst-env.in: Don't set 'NIX_BUILD_HOOK'.
* nix/libstore/build.cc (HookInstance::HookInstance): Run 'guix
offload'.
(DerivationGoal::tryBuildHook): Remove reference to 'NIX_BUILD_HOOK'.
* nix/nix-daemon/guix-daemon.cc (main) [HAVE_DAEMON_OFFLOAD_HOOK]: Don't
set 'NIX_BUILD_HOOK'.
* nix/nix-daemon/nix-daemon.cc (performOp) [!HAVE_DAEMON_OFFLOAD_HOOK]:
Leave 'settings.useBuildHook' unchanged.

1 files changed, 5 insertions, 6 deletions

diff --git a/nix/libstore/build.cc b/nix/libstore/build.cc
index fe7bf79069..9f1f88933a 100644
--- a/nix/libstore/build.cc
+++ b/nix/libstore/build.cc
@@ -614,9 +614,7 @@ HookInstance::HookInstance()
 {
     debug("starting build hook");
 
-    Path buildHook = getEnv("NIX_BUILD_HOOK");
-    if (string(buildHook, 0, 1) != "/") buildHook = settings.nixLibexecDir + "/nix/" + buildHook;
-    buildHook = canonPath(buildHook);
+    const Path &buildHook = settings.guixProgram;
 
     /* Create a pipe to get the output of the child. */
     fromHook.create();
@@ -642,13 +640,14 @@ HookInstance::HookInstance()
         if (dup2(builderOut.writeSide, 4) == -1)
             throw SysError("dupping builder's stdout/stderr");
 
-        execl(buildHook.c_str(), buildHook.c_str(), settings.thisSystem.c_str(),
+        execl(buildHook.c_str(), buildHook.c_str(), "offload",
+	    settings.thisSystem.c_str(),
             (format("%1%") % settings.maxSilentTime).str().c_str(),
             (format("%1%") % settings.printBuildTrace).str().c_str(),
             (format("%1%") % settings.buildTimeout).str().c_str(),
             NULL);
 
-        throw SysError(format("executing `%1%'") % buildHook);
+        throw SysError(format("executing `%1% offload'") % buildHook);
     });
 
     pid.setSeparatePG(true);
@@ -1581,7 +1580,7 @@ void DerivationGoal::buildDone()
 
 HookReply DerivationGoal::tryBuildHook()
 {
-    if (!settings.useBuildHook || getEnv("NIX_BUILD_HOOK") == "") return rpDecline;
+    if (!settings.useBuildHook) return rpDecline;
 
     if (!worker.hook)
         worker.hook = std::shared_ptr<HookInstance>(new HookInstance);