commit fba1c01f5ad1c8c5973200213fc44273a8ea3e78
from: Mark Jamsek <mark@jamsek.dev>
via: Thomas Adam <thomas@xteddy.org>
date: Fri Jan 03 10:46:48 2025 UTC

tog: fix log view race condition evinced by regress

When the commit graph has been traversed, we set the log_complete flag
to signal the main thread that we've completed iterating commit history,
which request_log_commits() checks and, if set, returns early instead of
calling trigger_log_thread(). If called, trigger_log_thread() wakes the
log thread, then waits on the log thread to unblock when another commit
has been loaded. There's a race between the log thread setting the
log_complete flag and request_log_commits() checking it, which causes
trigger_load_thread() to wait on a signal that never unblocks because
there are no more commits to be loaded.

ok stsp@

commit - 4cef9d7c76a821328add4b99dd9873b1cac5f827
commit + fba1c01f5ad1c8c5973200213fc44273a8ea3e78
blob - af194327c47dd9397d815e9ddd4ece646d627acc
blob + 3512ab341118eeaffa45969a14846501ab8387b2
--- tog/tog.c
+++ tog/tog.c
@@ -4025,6 +4025,8 @@ log_thread(void *arg)
 			    TAILQ_FIRST(&a->real_commits->head);
 			*a->selected_entry = *a->first_displayed_entry;
 		}
+		if (done)
+			a->log_complete = 1;
 
 		errcode = pthread_cond_signal(&a->commit_loaded);
 		if (errcode) {