1 files changed, 37 insertions, 8 deletions

diff --git a/src/libutil/serialise.cc b/src/libutil/serialise.cc
index 7476e6f6c..3d5121a19 100644
--- a/src/libutil/serialise.cc
+++ b/src/libutil/serialise.cc
@@ -20,7 +20,7 @@ void BufferedSink::operator () (std::string_view data)
            buffer size. */
         if (bufPos + data.size() >= bufSize) {
             flush();
-            write(data);
+            writeUnbuffered(data);
             break;
         }
         /* Otherwise, copy the bytes to the buffer.  Flush the buffer
@@ -38,7 +38,7 @@ void BufferedSink::flush()
     if (bufPos == 0) return;
     size_t n = bufPos;
     bufPos = 0; // don't trigger the assert() in ~BufferedSink()
-    write({buffer.get(), n});
+    writeUnbuffered({buffer.get(), n});
 }
 
 
@@ -48,7 +48,7 @@ FdSink::~FdSink()
 }
 
 
-void FdSink::write(std::string_view data)
+void FdSink::writeUnbuffered(std::string_view data)
 {
     written += data.size();
     try {
@@ -186,6 +186,22 @@ static DefaultStackAllocator defaultAllocatorSingleton;
 StackAllocator *StackAllocator::defaultAllocator = &defaultAllocatorSingleton;
 
 
+std::shared_ptr<void> (*create_coro_gc_hook)() = []() -> std::shared_ptr<void> {
+    return {};
+};
+
+/* This class is used for entry and exit hooks on coroutines */
+class CoroutineContext {
+    /* Disable GC when entering the coroutine without the boehm patch,
+     * since it doesn't find the main thread stack in this case.
+     * std::shared_ptr<void> performs type-erasure, so it will call the right
+     * deleter. */
+    const std::shared_ptr<void> coro_gc_hook = create_coro_gc_hook();
+public:
+    CoroutineContext() {};
+    ~CoroutineContext() {};
+};
+
 std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun)
 {
     struct SourceToSink : FinishSink
@@ -206,7 +222,8 @@ std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun)
             if (in.empty()) return;
             cur = in;
 
-            if (!coro)
+            if (!coro) {
+                CoroutineContext ctx;
                 coro = coro_t::push_type(VirtualStackAllocator{}, [&](coro_t::pull_type & yield) {
                     LambdaSource source([&](char *out, size_t out_len) {
                         if (cur.empty()) {
@@ -223,17 +240,24 @@ std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun)
                     });
                     fun(source);
                 });
+            }
 
             if (!*coro) { abort(); }
 
-            if (!cur.empty()) (*coro)(false);
+            if (!cur.empty()) {
+                CoroutineContext ctx;
+                (*coro)(false);
+            }
         }
 
         void finish() override
         {
             if (!coro) return;
             if (!*coro) abort();
-            (*coro)(true);
+            {
+                CoroutineContext ctx;
+                (*coro)(true);
+            }
             if (*coro) abort();
         }
     };
@@ -264,18 +288,23 @@ std::unique_ptr<Source> sinkToSource(
 
         size_t read(char * data, size_t len) override
         {
-            if (!coro)
+            if (!coro) {
+                CoroutineContext ctx;
                 coro = coro_t::pull_type(VirtualStackAllocator{}, [&](coro_t::push_type & yield) {
                     LambdaSink sink([&](std::string_view data) {
                         if (!data.empty()) yield(std::string(data));
                     });
                     fun(sink);
                 });
+            }
 
             if (!*coro) { eof(); abort(); }
 
             if (pos == cur.size()) {
-                if (!cur.empty()) (*coro)();
+                if (!cur.empty()) {
+                    CoroutineContext ctx;
+                    (*coro)();
+                }
                 cur = coro->get();
                 pos = 0;
             }