From 254e1bd3a38f1317496de4fe8af794f50ec51183 Mon Sep 17 00:00:00 2001
From: Gianmatteo Palmieri <mail@gian.im>
Date: Fri, 19 Jul 2024 15:56:36 +0200
Subject: [PATCH] fix(libsinsp): disable thread pool on webassembly

Signed-off-by: Gianmatteo Palmieri <mail@gian.im>
---
 userspace/libsinsp/plugin.cpp              | 10 ++++++++++
 userspace/libsinsp/sinsp.cpp               |  7 ++++++-
 userspace/libsinsp/test/plugins.ut.cpp     |  6 ++++++
 userspace/libsinsp/test/thread_pool.ut.cpp |  4 +++-
 userspace/plugin/plugin_api.h              |  2 +-
 5 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/userspace/libsinsp/plugin.cpp b/userspace/libsinsp/plugin.cpp
index 4b91a4a2ec..ec98143c62 100755
--- a/userspace/libsinsp/plugin.cpp
+++ b/userspace/libsinsp/plugin.cpp
@@ -824,6 +824,11 @@ std::vector<metrics_v2> sinsp_plugin::get_metrics() const
 
 thread_pool::routine_id_t sinsp_plugin::subscribe_routine(ss_plugin_routine_fn_t routine_fn, ss_plugin_routine_state_t* routine_state)
 {
+	if(!m_thread_pool)
+	{
+		return static_cast<thread_pool::routine_id_t>(nullptr);
+	}
+
 	auto f = [this, routine_fn, routine_state]() -> bool {
 		return static_cast<bool>(routine_fn(m_state, routine_state));
 	};
@@ -833,6 +838,11 @@ thread_pool::routine_id_t sinsp_plugin::subscribe_routine(ss_plugin_routine_fn_t
 
 void sinsp_plugin::unsubscribe_routine(thread_pool::routine_id_t routine_id)
 {
+	if(!m_thread_pool || !routine_id)
+	{
+		return;
+	}
+
 	m_thread_pool->unsubscribe(routine_id);
 }
 
diff --git a/userspace/libsinsp/sinsp.cpp b/userspace/libsinsp/sinsp.cpp
index 3eb745941d..cd0b813662 100644
--- a/userspace/libsinsp/sinsp.cpp
+++ b/userspace/libsinsp/sinsp.cpp
@@ -132,7 +132,9 @@ sinsp::sinsp(bool static_container, const std::string &static_id, const std::str
 	m_table_registry = std::make_shared<libsinsp::state::table_registry>();
 	m_table_registry->add_table(m_thread_manager.get());
 
+#if !defined(__EMSCRIPTEN__)
 	m_thread_pool = std::make_shared<bs_thread_pool>();
+#endif
 }
 
 sinsp::~sinsp()
@@ -798,7 +800,10 @@ void sinsp::close()
 	}
 
 	// purge pending routines and wait for the running ones
-	m_thread_pool->purge();
+	if(m_thread_pool)
+	{
+		m_thread_pool->purge();
+	}
 
 	m_mode = SINSP_MODE_NONE;
 }
diff --git a/userspace/libsinsp/test/plugins.ut.cpp b/userspace/libsinsp/test/plugins.ut.cpp
index d3a413c30f..de24a3bc64 100644
--- a/userspace/libsinsp/test/plugins.ut.cpp
+++ b/userspace/libsinsp/test/plugins.ut.cpp
@@ -921,11 +921,15 @@ TEST_F(sinsp_with_test_input, plugin_metrics)
 
 #endif
 
+#if !defined(__EMSCRIPTEN__)
+
 TEST_F(sinsp_with_test_input, plugin_routines)
 {
 	auto p = register_plugin(&m_inspector, get_plugin_api_sample_routines);
 	open_inspector();
 
+	ASSERT_NE(m_inspector.m_thread_pool, nullptr);
+
 	// step #0: the plugins subscribes a routine on capture open
 	auto routines_num = m_inspector.m_thread_pool->routines_num();
 	ASSERT_EQ(routines_num, 1);
@@ -957,3 +961,5 @@ TEST_F(sinsp_with_test_input, plugin_routines)
 	routines_num = m_inspector.m_thread_pool->routines_num();
 	ASSERT_EQ(routines_num, 0);
 }
+
+#endif
diff --git a/userspace/libsinsp/test/thread_pool.ut.cpp b/userspace/libsinsp/test/thread_pool.ut.cpp
index ec8265c487..b4124110fc 100644
--- a/userspace/libsinsp/test/thread_pool.ut.cpp
+++ b/userspace/libsinsp/test/thread_pool.ut.cpp
@@ -19,6 +19,7 @@ limitations under the License.
 #include <gtest/gtest.h>
 #include <sinsp_with_test_input.h>
 
+#if !defined(__EMSCRIPTEN__)
 TEST_F(sinsp_with_test_input, thread_pool)
 {
     open_inspector();
@@ -69,4 +70,5 @@ TEST_F(sinsp_with_test_input, thread_pool)
     ASSERT_EQ(tp->routines_num(), 1);
     m_inspector.close();
     ASSERT_EQ(tp->routines_num(), 0);
-}
\ No newline at end of file
+}
+#endif
\ No newline at end of file
diff --git a/userspace/plugin/plugin_api.h b/userspace/plugin/plugin_api.h
index b0b6a476fb..14a373e78b 100644
--- a/userspace/plugin/plugin_api.h
+++ b/userspace/plugin/plugin_api.h
@@ -416,7 +416,7 @@ typedef struct
 	// - f: the function executed by the routine on each iteration
 	// - i: the routine's state
 	//
-	// Return value: A routine handle that can be used to later unsubscribe the routine.
+	// Return value: A routine handle that can be used to later unsubscribe the routine. Returns null in case of failure.
 	ss_plugin_routine_t* (*subscribe)(ss_plugin_owner_t* o, ss_plugin_routine_fn_t f, ss_plugin_routine_state_t* i);
 
 	//