commit 095eff81ffffff345369c74054c9e3f263ff3534
author Patrick Williams <patrick@stwcx.xyz> Thu Sep 22 17:44:30 2022 -0500
committer Patrick Williams <patrick@stwcx.xyz> Fri Oct 14 06:35:51 2022 -0500
tree 89381ba3470d2c135ec220abada8df2df22c74a5
parent 4cfc284dace92fa0a825d5adbadd7b02543a303c

async: scope: allow blocks before started

In some cases it may be helpful to be able to block on a scope
before work has begun on that scope.  Add state tracking to know
when the scope has first started.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I9ee48aa19344b80124aa9409a4a7e368eb025882

src/async/scope.cpp

diff --git a/src/async/scope.cpp b/src/async/scope.cpp
index 353c52b..a990e41 100644
--- a/src/async/scope.cpp
+++ b/src/async/scope.cpp
@@ -16,6 +16,7 @@
 void scope::started_task() noexcept
 {
     std::lock_guard l{lock};
+    started = true;
     ++pending_count;
 }
 
@@ -74,7 +75,11 @@
 
     {
         std::lock_guard l{s.lock};
-        if (s.pending_count == 0)
+        if (!s.started)
+        {
+            done = false;
+        }
+        else if (s.pending_count == 0)
         {
             done = true;
         }