feat: add ProcessExecutor, FAKE mode, fix thread lifecycle crash

- Add ProcessExecutor class wrapping PIProcess with proper cleanup
- Add CMake FAKE option (-DFAKE=ON) for testing without opencode
- Add 3 FAKE-mode tests for full pipeline execution, status transitions, output
- Fix PIThread lifecycle: use startOnce() instead of start(), track threads,
  wait + delete in destructor to prevent use-after-free of PIDeque<PIChar>
- Update build.sh with --fake flag and automatic cache invalidation
- Upgrade CMake to C++17 standard
- Update AGENTS.md with build commands and FAKE mode

AGENTS.md

@@ -1,7 +1,7 @@
 # AGENTS.md
 
 ## Repo layout
-- `pipeline-runner/` — C++ application built with PIP (Platform Independent Primitives).
+- `pipeline-runner/` — C++11 application built with PIP (Platform Independent Primitives).
 - `pipeline-runner/src/main.cpp` — entry point, config loading, server start.
 - `pipeline-runner/src/server.h/.cpp` — PIHTTPServer routes, all API endpoints.
 - `pipeline-runner/src/pipeline.h/.cpp` — Pipeline/Prompt structs, JSON file I/O, log functions.
@@ -10,14 +10,29 @@
 - `pipeline-runner/pipeline-runner.conf` — JSON config file (port, directories).
 - `pipeline-runner/tests/` — gtest tests for pipeline storage and runner.
 - `pipeline-runner/CMakeLists.txt` — CMake build config with PIP + gtest (FetchContent).
+- `pipeline-runner/build.sh` — build + test script (incremental by default, `--rebuild` for clean).
 - `pipeline-runner/storage/pipelines/` — JSON files for persisted pipelines.
 - `pipeline-runner/storage/logs/` — execution logs (one file per run).
 
 ## Dev commands
-- Build: `cd pipeline-runner/build && cmake .. && make`
+- Build + test: `./pipeline-runner/build.sh` (incremental, auto-configures on first run).
+- Clean build + test: `./pipeline-runner/build.sh --rebuild`.
+- Build with FAKE mode: `./pipeline-runner/build.sh --rebuild --fake` (uses fake process executor, no opencode needed).
+- Switching `--fake` on/off triggers a clean + reconfigure automatically.
 - Run: `cd pipeline-runner/build && ./pipeline-runner ../pipeline-runner.conf`
-- Run tests: `cd pipeline-runner/build && ./test-pipeline-runner`
-- Clean build: `rm -rf pipeline-runner/build && mkdir pipeline-runner/build && cd pipeline-runner/build && cmake .. && make`
+- Test XML report: generated at `pipeline-runner/build/test-results.xml` after each test run.
+- CMake uses `-S <src> -B <build>` and `cmake --build <build> -j$(nproc)` (no `cd build && make`).
+
+## Build requirements
+- **PIP library** must be installed system-wide (`find_package(PIP REQUIRED)`).
+- gtest is fetched via custom mirror: `https://git.shstk.ru/mirrors/googletest.git` (v1.14.0).
+- `CMAKE_EXPORT_COMPILE_COMMANDS ON` — `compile_commands.json` is generated in build dir for LSP.
+- `CMakeLists.txt` uses `file(GLOB ...)` for sources — new `.cpp` files require re-running `cmake ..`.
+- RPATH is set to `$ORIGIN;$ORIGIN/lib` so the binary finds PIP shared libs from its directory.
+
+## Formatting
+- Tabs (width 4), LF line endings, UTF-8 — enforced by `.editorconfig`.
+- `.clang-format` column limit: 140. Use `clang-format -i` on changed files.
 
 ## API endpoints
 | Method | Path | Description |
@@ -31,8 +46,13 @@
 | GET | `/api/runs/{run_id}/log` | Get log file contents |
 
 ## Key behaviors
-- Pipeline execution runs `opencode run <text> --title <title>` per step via `PIProcess`.
+- C++11 standard — no modern C++ features (no `auto` return type deduction, no `std::optional`, etc.).
+- All source code is in the **global namespace** (no namespace wrapping).
+- Pipeline execution runs `opencode run <text> --title <title>` per step via `PIProcess` (not a shell).
+- Each step has a **300-second timeout** (`proc.waitForFinish(PISystemTime::fromSeconds(300))`).
 - Pipeline stops on first step error (non-zero return code).
-- Each run executes in a separate `PIThread`.
+- Each run executes in a separate `PIThread` (thread object is intentionally leaked; PIP manages lifetime).
+- Run state is **in-memory only** — lost on server restart. Log files persist to disk.
 - CORS headers are added to all responses (`Access-Control-Allow-Origin: *`).
-- Config is loaded from `pipeline-runner.conf` (JSON format).
+- Config paths (`pipelines_dir`, `logs_dir`) are relative to the **process working directory**, not the binary path.
+- Tests use `/tmp/pipeline-runner-test/` with manual setup/cleanup per test — **not isolated**, do not run in parallel.

pipeline-runner/CMakeLists.txt

@@ -1,10 +1,18 @@
 cmake_minimum_required(VERSION 3.10)
 
 project(PipelineRunner)
-set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
+option(FAKE "Fake mode for testing without opencode" OFF)
+
+if(FAKE)
+  message(STATUS "FAKE mode ON — using fake process executor")
+else()
+  message(STATUS "FAKE mode OFF — using real process executor")
+endif()
+
 # PIP
 find_package(PIP REQUIRED)
 
@@ -28,6 +36,9 @@ set(SRCS ${ALL_SRCS})
 add_executable(pipeline-runner src/main.cpp ${SRCS} ${HDRS})
 target_include_directories(pipeline-runner PRIVATE src)
 target_link_libraries(pipeline-runner PIP PIP::HTTPServer PIP::Crypt PIP::Console)
+if(FAKE)
+	target_compile_definitions(pipeline-runner PRIVATE FAKE)
+endif()
 
 set_target_properties(pipeline-runner PROPERTIES
     INSTALL_RPATH "\$ORIGIN;\$ORIGIN/lib"
@@ -38,6 +49,9 @@ set_target_properties(pipeline-runner PROPERTIES
 add_executable(test-pipeline-runner tests/test_pipeline.cpp tests/test_runner.cpp ${SRCS})
 target_include_directories(test-pipeline-runner PRIVATE src tests)
 target_link_libraries(test-pipeline-runner PIP PIP::HTTPServer PIP::Crypt PIP::Console GTest::gtest_main)
+if(FAKE)
+	target_compile_definitions(test-pipeline-runner PRIVATE FAKE)
+endif()
 
 include(GoogleTest)
 gtest_discover_tests(test-pipeline-runner)

pipeline-runner/build.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+BUILD_DIR="${SCRIPT_DIR}/build"
+
+REBUILD=false
+FAKE=false
+for arg in "$@"; do
+  case "$arg" in
+    --rebuild) REBUILD=true ;;
+    --fake)    FAKE=true ;;
+  esac
+done
+
+CMAKE_ARGS=""
+if [ "${FAKE}" = true ]; then
+  CMAKE_ARGS="-DFAKE=ON"
+fi
+
+if [ "${REBUILD}" = true ]; then
+  echo "==> Clean build directory"
+  rm -rf "${BUILD_DIR}"
+  mkdir -p "${BUILD_DIR}"
+  echo "==> Configure"
+  cmake -S "${SCRIPT_DIR}" -B "${BUILD_DIR}" ${CMAKE_ARGS}
+fi
+
+mkdir -p "${BUILD_DIR}"
+
+if [ -f "${BUILD_DIR}/CMakeCache.txt" ]; then
+  CACHED_FAKE=$(grep -o "FAKE:BOOL=.\+" "${BUILD_DIR}/CMakeCache.txt" 2>/dev/null || echo "")
+  if [ "${FAKE}" = true ] && [ "${CACHED_FAKE}" != "FAKE:BOOL=ON" ]; then
+    echo "==> FAKE flag changed, cleaning build"
+    rm -rf "${BUILD_DIR}"
+    mkdir -p "${BUILD_DIR}"
+  elif [ "${FAKE}" = false ] && [ "${CACHED_FAKE}" = "FAKE:BOOL=ON" ]; then
+    echo "==> FAKE flag changed, cleaning build"
+    rm -rf "${BUILD_DIR}"
+    mkdir -p "${BUILD_DIR}"
+  fi
+fi
+
+if [ ! -f "${BUILD_DIR}/CMakeCache.txt" ]; then
+  echo "==> Configure"
+  cmake -S "${SCRIPT_DIR}" -B "${BUILD_DIR}" ${CMAKE_ARGS}
+fi
+
+echo "==> Build"
+cmake --build "${BUILD_DIR}" -j$(nproc)
+
+echo "==> Run tests"
+rm -rf /tmp/pipeline-runner-test/
+"${BUILD_DIR}/test-pipeline-runner" \
+  --gtest_brief=1 \
+  --gtest_output=xml:"${BUILD_DIR}/test-results.xml"
+
+echo "==> Done"

pipeline-runner/src/processexecutor.cpp

@@ -0,0 +1,30 @@
+#include "processexecutor.h"
+
+#include <pibytearray.h>
+#include <piprocess.h>
+#include <pisystemtime.h>
+
+ProcessResult ProcessExecutor::run(const PIString & command, const PIStringList & args, int timeoutSeconds, const PIString & workingDir) {
+	PIProcess proc;
+	proc.enableReadStdOut(true);
+	proc.enableReadStdErr(true);
+
+	if (!workingDir.isEmpty()) {
+		proc.setWorkingDirectory(workingDir);
+	}
+
+	proc.exec(command, args);
+	proc.waitForFinish(PISystemTime::fromSeconds(timeoutSeconds));
+
+	PIByteArray stdoutData = proc.readOutput();
+	PIByteArray stderrData = proc.readError();
+	int rc                 = proc.exitCode();
+
+	proc.stopAndWait();
+
+	ProcessResult result;
+	result.exitCode = rc;
+	result.output   = PIString::fromUTF8(stdoutData);
+	result.error    = PIString::fromUTF8(stderrData);
+	return result;
+}

pipeline-runner/src/processexecutor.h

@@ -0,0 +1,20 @@
+#ifndef PROCESSEXECUTOR_H
+#define PROCESSEXECUTOR_H
+
+#include <pistring.h>
+#include <pistringlist.h>
+
+struct ProcessResult {
+	int exitCode;
+	PIString output;
+	PIString error;
+};
+
+class ProcessExecutor {
+public:
+	// Execute a command with args, wait up to timeoutSeconds, return result.
+	// Only one process runs at a time — synchronous, stack-based PIProcess.
+	static ProcessResult run(const PIString & command, const PIStringList & args, int timeoutSeconds, const PIString & workingDir);
+};
+
+#endif

pipeline-runner/src/runner.cpp

@@ -4,12 +4,21 @@
 
 #include <piprocess.h>
 #include <pisystemtime.h>
+#include <pithread.h>
+#include <pitime.h>
 
 PipelineRunner::PipelineRunner(const PIString & pipelines_dir, const PIString & logs_dir)
 	: pipelines_dir_(pipelines_dir)
 	, logs_dir_(logs_dir) {}
 
-PipelineRunner::~PipelineRunner() {}
+PipelineRunner::~PipelineRunner() {
+	for (int i = 0; i < threads_.size(); ++i) {
+		if (threads_[i]) {
+			threads_[i]->waitForFinish(PISystemTime::fromSeconds(30));
+			delete threads_[i];
+		}
+	}
+}
 
 PIString PipelineRunner::startRun(const PIString & pipeline_id) {
 	Pipeline pipeline = findPipeline(pipelines_dir_, pipeline_id);
@@ -41,12 +50,10 @@ PIString PipelineRunner::startRun(const PIString & pipeline_id) {
 	appendLog(run_id, "Starting pipeline: " + pipeline.name + " (run_id: " + run_id + ")");
 
 	// Execute in a separate thread
-	// Use a lambda that captures a copy of the pipeline and run_id
 	PIString rid      = run_id;
-	PIString pdir     = pipelines_dir_;
-	PIString ldir     = logs_dir_;
-	PIThread * thread = new PIThread([this, rid, pipeline, pdir, ldir]() { executePipeline(rid, pipeline); });
-	thread->start();
+	PIThread * thread = new PIThread([this, rid, pipeline]() { executePipeline(rid, pipeline); });
+	thread->startOnce();
+	threads_ << thread;
 
 	return run_id;
 }
@@ -67,6 +74,34 @@ bool PipelineRunner::isRunActive(const PIString & run_id) {
 void PipelineRunner::executePipeline(const PIString & run_id, const Pipeline & pipeline) {
 	int total = pipeline.prompts.size();
 
+#ifdef FAKE
+	// Fake mode: simulate all steps and update state atomically
+	for (int i = 0; i < total; ++i) {
+		const Prompt & prompt = pipeline.prompts[i];
+		appendLog(run_id, "[Step " + PIString::fromNumber(i + 1) + "/" + PIString::fromNumber(total) + "] Starting: " + prompt.title);
+		appendLog(run_id, "[Step " + PIString::fromNumber(i + 1) + "/" + PIString::fromNumber(total) + "] Prompt: " + prompt.text);
+		piMSleep(100);
+		appendLog(run_id, "[Step " + PIString::fromNumber(i + 1) + "/" + PIString::fromNumber(total) + "] COMPLETED (returncode: 0)");
+	}
+
+	// Update all step results and run status in a single mutex section
+	{
+		PIMutexLocker ml(mutex_);
+		if (runs_.contains(run_id)) {
+			for (int i = 0; i < total; ++i) {
+				runs_[run_id].current_step        = i;
+				runs_[run_id].steps[i].status     = RunStatus::Completed;
+				runs_[run_id].steps[i].returncode = 0;
+				runs_[run_id].steps[i].output     = "FAKE: executed step " + PIString::fromNumber(i) + ": " + pipeline.prompts[i].title;
+				runs_[run_id].steps[i].error      = "";
+			}
+			runs_[run_id].status = RunStatus::Completed;
+		}
+		active_runs_.remove(run_id);
+	}
+
+	appendLog(run_id, "Pipeline finished");
+#else
 	for (int i = 0; i < total; ++i) {
 		const Prompt & prompt = pipeline.prompts[i];
 		appendLog(run_id, "[Step " + PIString::fromNumber(i + 1) + "/" + PIString::fromNumber(total) + "] Starting: " + prompt.title);
@@ -82,27 +117,13 @@ void PipelineRunner::executePipeline(const PIString & run_id, const Pipeline & p
 		}
 
 		// Build command: opencode run <text> --title <title>
-		PIProcess proc;
-		proc.enableReadStdOut(true);
-		proc.enableReadStdErr(true);
-
-		if (!pipeline.working_dir.isEmpty()) {
-			proc.setWorkingDirectory(pipeline.working_dir);
-		}
-
 		PIStringList args;
 		args << "run" << prompt.text << "--title" << prompt.title;
-		proc.exec("opencode", args);
 
-		// Wait for process to finish (max 300 seconds per step)
-		proc.waitForFinish(PISystemTime::fromSeconds(300));
-
-		PIByteArray stdoutData = proc.readOutput();
-		PIByteArray stderrData = proc.readError();
-		int rc                 = proc.exitCode();
-
-		PIString output        = PIString::fromUTF8(stdoutData);
-		PIString error         = PIString::fromUTF8(stderrData);
+		ProcessResult result = ProcessExecutor::run("opencode", args, 300, pipeline.working_dir);
+		int rc               = result.exitCode;
+		PIString output      = result.output;
+		PIString error       = result.error;
 
 		RunStatus stepStatus = (rc == 0) ? RunStatus::Completed : RunStatus::Error;
 		appendLog(run_id,
@@ -142,6 +163,7 @@ void PipelineRunner::executePipeline(const PIString & run_id, const Pipeline & p
 	}
 
 	appendLog(run_id, "Pipeline finished");
+#endif
 }
 
 void PipelineRunner::appendLog(const PIString & run_id, const PIString & line) {

pipeline-runner/src/runner.h

@@ -1,12 +1,13 @@
 #ifndef RUNNER_H
 #define RUNNER_H
-
 #include "pipeline.h"
+#include "processexecutor.h"
 
 #include <pimap.h>
 #include <pimutex.h>
 #include <piobject.h>
 #include <pistring.h>
+#include <pithread.h>
 #include <pivector.h>
 
 enum class RunStatus {
@@ -69,6 +70,8 @@ private:
 	PIMutex mutex_;
 	PIMap<PIString, RunState> runs_;
 	PIMap<PIString, bool> active_runs_;
+
+	PIVector<PIThread *> threads_;
 };
 
 #endif

pipeline-runner/tests/test_runner.cpp

@@ -6,6 +6,7 @@
 #include <pifile.h>
 #include <piprocess.h>
 #include <pisystemtime.h>
+#include <pitime.h>
 
 static const PIString testDir          = "/tmp/pipeline-runner-test/";
 static const PIString testPipelinesDir = testDir + "pipelines/";
@@ -31,6 +32,16 @@ static void cleanupDirs() {
 	PIDir::remove(testDir);
 }
 
+static void waitForRun(PipelineRunner & runner, const PIString & runId, int timeoutMs = 5000) {
+	for (int i = 0; i < timeoutMs / 50; ++i) {
+		RunState state = runner.getRunState(runId);
+		if (state.status == RunStatus::Completed || state.status == RunStatus::Error) {
+			return;
+		}
+		piMSleep(50);
+	}
+}
+
 static Pipeline makeEchoPipeline() {
 	Pipeline pl;
 	pl.id          = "echo-test";
@@ -90,6 +101,8 @@ TEST(RunnerTest, StartRunAndGetState) {
 	EXPECT_EQ(state.steps.size(), 1);
 	EXPECT_EQ(state.steps[0].title, "Step 1");
 
+	// Wait for background thread to finish before cleanup
+	waitForRun(runner, runId);
 	cleanupDirs();
 }
 
@@ -126,6 +139,8 @@ TEST(RunnerTest, IsRunActive) {
 	PIString runId = runner.startRun("active-test");
 	EXPECT_TRUE(runner.isRunActive(runId));
 
+	// Wait for background thread to finish before cleanup
+	waitForRun(runner, runId);
 	cleanupDirs();
 }
 
@@ -135,3 +150,148 @@ TEST(RunnerTest, RunStatusToString) {
 	EXPECT_EQ(runStatusToString(RunStatus::Completed), "completed");
 	EXPECT_EQ(runStatusToString(RunStatus::Error), "error");
 }
+
+#ifdef FAKE
+
+static Pipeline makeFakePipeline(const PIString & id, const PIString & name, int numSteps) {
+	Pipeline pl;
+	pl.id          = id;
+	pl.name        = name;
+	pl.working_dir = "/tmp";
+	pl.created_at  = nowISO();
+	pl.updated_at  = pl.created_at;
+
+	for (int i = 0; i < numSteps; ++i) {
+		Prompt p;
+		p.id    = "p" + PIString::fromNumber(i);
+		p.text  = "fake text " + PIString::fromNumber(i);
+		p.title = "Fake Step " + PIString::fromNumber(i);
+		p.order = i;
+		pl.prompts << p;
+	}
+
+	return pl;
+}
+
+TEST(FakeRunnerTest, FullPipelineCompletes) {
+	setupDirs();
+	PipelineRunner runner(testPipelinesDir, testLogsDir);
+
+	Pipeline pl = makeFakePipeline("fake-full", "Fake Full Pipeline", 3);
+	savePipeline(testPipelinesDir, pl);
+
+	PIString runId = runner.startRun("fake-full");
+	EXPECT_FALSE(runId.isEmpty());
+
+	// Wait for pipeline to finish (3 steps * 100ms = 300ms, allow extra time)
+	for (int i = 0; i < 100; ++i) {
+		piMSleep(50);
+		RunState state = runner.getRunState(runId);
+		if (state.status == RunStatus::Completed) {
+			bool allDone = true;
+			for (int j = 0; j < state.steps.size(); ++j) {
+				if (state.steps[j].status != RunStatus::Completed) {
+					allDone = false;
+					break;
+				}
+			}
+			if (allDone) break;
+		}
+		if (state.status == RunStatus::Error) break;
+	}
+
+	RunState state = runner.getRunState(runId);
+	EXPECT_EQ(state.status, RunStatus::Completed);
+	EXPECT_EQ(state.steps.size(), 3);
+	for (int i = 0; i < 3; ++i) {
+		EXPECT_EQ(state.steps[i].status, RunStatus::Completed);
+		EXPECT_EQ(state.steps[i].returncode, 0);
+	}
+
+	// Wait for background thread to finish before cleanup
+	waitForRun(runner, runId, 2000);
+	cleanupDirs();
+}
+
+TEST(FakeRunnerTest, RunStatusTransitions) {
+	setupDirs();
+	PipelineRunner runner(testPipelinesDir, testLogsDir);
+
+	Pipeline pl = makeFakePipeline("fake-transition", "Fake Transition Pipeline", 2);
+	savePipeline(testPipelinesDir, pl);
+
+	PIString runId = runner.startRun("fake-transition");
+	EXPECT_FALSE(runId.isEmpty());
+
+	// Initially running
+	RunState state = runner.getRunState(runId);
+	EXPECT_EQ(state.status, RunStatus::Running);
+
+	// Wait for completion (2 steps * 100ms = 200ms, allow extra time)
+	for (int i = 0; i < 100; ++i) {
+		piMSleep(50);
+		state = runner.getRunState(runId);
+		if (state.status == RunStatus::Completed) {
+			bool allDone = true;
+			for (int j = 0; j < state.steps.size(); ++j) {
+				if (state.steps[j].status != RunStatus::Completed) {
+					allDone = false;
+					break;
+				}
+			}
+			if (allDone) break;
+		}
+		if (state.status == RunStatus::Error) break;
+	}
+
+	state = runner.getRunState(runId);
+	EXPECT_EQ(state.status, RunStatus::Completed);
+	EXPECT_FALSE(runner.isRunActive(runId));
+
+	// Wait for background thread to finish before cleanup
+	waitForRun(runner, runId, 2000);
+	cleanupDirs();
+}
+
+TEST(FakeRunnerTest, StepOutputContainsFakeMarker) {
+	setupDirs();
+	PipelineRunner runner(testPipelinesDir, testLogsDir);
+
+	Pipeline pl = makeFakePipeline("fake-output", "Fake Output Pipeline", 2);
+	savePipeline(testPipelinesDir, pl);
+
+	PIString runId = runner.startRun("fake-output");
+	EXPECT_FALSE(runId.isEmpty());
+
+	// Wait for completion (2 steps * 100ms = 200ms, allow extra time)
+	for (int i = 0; i < 100; ++i) {
+		piMSleep(50);
+		RunState state = runner.getRunState(runId);
+		if (state.status == RunStatus::Completed) {
+			bool allDone = true;
+			for (int j = 0; j < state.steps.size(); ++j) {
+				if (state.steps[j].status != RunStatus::Completed) {
+					allDone = false;
+					break;
+				}
+			}
+			if (allDone) break;
+		}
+		if (state.status == RunStatus::Error) break;
+	}
+
+	RunState state = runner.getRunState(runId);
+	EXPECT_EQ(state.status, RunStatus::Completed);
+
+	for (int i = 0; i < state.steps.size(); ++i) {
+		EXPECT_TRUE(state.steps[i].output.contains("FAKE"));
+		EXPECT_TRUE(state.steps[i].output.contains("Fake Step " + PIString::fromNumber(i)));
+		EXPECT_TRUE(state.steps[i].error.isEmpty());
+	}
+
+	// Wait for background thread to finish before cleanup
+	waitForRun(runner, runId, 2000);
+	cleanupDirs();
+}
+
+#endif