From b04521e4ecfe84816c8a2bb34644fd4d5a59cb83 Mon Sep 17 00:00:00 2001
From: eldritch horrors <pennae@lix.systems>
Date: Sat, 11 Oct 2025 21:59:56 +0200
Subject: [PATCH] libstore: move log handling fully into handleBuilderOutput

it was split up like this only because the old worker system had no
promises. since we have them now we can use them for encapsulation.

Change-Id: Idbd523eff617d4c53c14b125ab3dfce4979cdab1
---
 lix/libstore/build/derivation-goal.cc | 45 ++++++++++++++-------------
 lix/libstore/build/derivation-goal.hh |  4 ---
 2 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/lix/libstore/build/derivation-goal.cc b/lix/libstore/build/derivation-goal.cc
index ca024c960..27bfef0d1 100644
--- a/lix/libstore/build/derivation-goal.cc
+++ b/lix/libstore/build/derivation-goal.cc
@@ -1229,6 +1229,30 @@ Goal::WorkResult DerivationGoal::tooMuchLogs()
 kj::Promise<Result<std::optional<Goal::WorkResult>>>
 DerivationGoal::handleBuilderOutput(AsyncInputStream & in) noexcept
 try {
+    std::string currentLogLine;
+    size_t currentLogLinePos = 0; // to handle carriage return
+
+    auto flushLine = [&] {
+        KJ_DEFER({
+            currentLogLine = "";
+            currentLogLinePos = 0;
+        });
+
+        if (const auto state = handleJSONLogMessage(
+                currentLogLine, *act, builderActivities, "the derivation builder", false
+            ))
+        {
+            return *state;
+        } else {
+            logTail.push_back(currentLogLine);
+            if (logTail.size() > settings.logLines) {
+                logTail.pop_front();
+            }
+
+            return act->result(resBuildLogLine, currentLogLine);
+        }
+    };
+
     auto buf = kj::heapArray<char>(4096);
     while (true) {
         std::string_view data;
@@ -1417,27 +1441,6 @@ DerivationGoal::handleChildStreams(AsyncInputStream * builderIn, AsyncInputStrea
     co_return std::nullopt;
 }
 
-Logger::BufferState DerivationGoal::flushLine()
-{
-    KJ_DEFER({
-        currentLogLine = "";
-        currentLogLinePos = 0;
-    });
-
-    if (const auto state = handleJSONLogMessage(
-            currentLogLine, *act, builderActivities, "the derivation builder", false
-        ))
-    {
-        return *state;
-    } else {
-        logTail.push_back(currentLogLine);
-        if (logTail.size() > settings.logLines) logTail.pop_front();
-
-        return act->result(resBuildLogLine, currentLogLine);
-    }
-}
-
-
 kj::Promise<Result<OutputPathMap>> DerivationGoal::queryDerivationOutputMap()
 try {
     OutputPathMap res;
diff --git a/lix/libstore/build/derivation-goal.hh b/lix/libstore/build/derivation-goal.hh
index 2df3adf42..8bd7b2975 100644
--- a/lix/libstore/build/derivation-goal.hh
+++ b/lix/libstore/build/derivation-goal.hh
@@ -201,9 +201,6 @@ struct DerivationGoal : public Goal
      */
     std::list<std::string> logTail;
 
-    std::string currentLogLine;
-    size_t currentLogLinePos = 0; // to handle carriage return
-
     std::string currentHookLine;
 
     /**
@@ -325,7 +322,6 @@ protected:
     kj::Promise<Result<std::optional<WorkResult>>> handleHookOutput(AsyncInputStream & in) noexcept;
     kj::Promise<Result<std::optional<WorkResult>>> monitorForSilence() noexcept;
     WorkResult tooMuchLogs();
-    Logger::BufferState flushLine();
 
     virtual std::string buildErrorContents(const std::string & exitMsg, bool diskFull);