From 09806d757675912cebfb0789296343552fc4b7c0 Mon Sep 17 00:00:00 2001
From: Geza Lore <gezalore@gmail.com>
Date: Mon, 29 Jun 2020 17:27:43 +0100
Subject: [PATCH] Update fstapi.c to latest (fix undefined thread behaviour)

---
 include/gtkwave/fstapi.c | 21 +++++++++++++++++++--
 test_regress/driver.pl   |  9 ---------
 2 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/include/gtkwave/fstapi.c b/include/gtkwave/fstapi.c
index 8540587bb..8c95f7bfe 100644
--- a/include/gtkwave/fstapi.c
+++ b/include/gtkwave/fstapi.c
@@ -794,6 +794,7 @@ pthread_t thread;
 pthread_attr_t thread_attr;
 struct fstWriterContext *xc_parent;
 #endif
+unsigned in_pthread : 1;
 
 size_t fst_orig_break_size;
 size_t fst_orig_break_add_size;
@@ -1806,10 +1807,9 @@ static void *fstWriterFlushContextPrivate1(void *ctx)
 {
 struct fstWriterContext *xc = (struct fstWriterContext *)ctx;
 
+pthread_mutex_lock(&(xc->xc_parent->mutex));
 fstWriterFlushContextPrivate2(xc);
 
-pthread_mutex_unlock(&(xc->xc_parent->mutex));
-
 #ifdef FST_REMOVE_DUPLICATE_VC
 free(xc->curval_mem);
 #endif
@@ -1818,6 +1818,9 @@ free(xc->vchg_mem);
 tmpfile_close(&xc->tchn_handle, &xc->tchn_handle_nam);
 free(xc);
 
+xc->xc_parent->in_pthread = 0;
+pthread_mutex_unlock(&(xc->xc_parent->mutex));
+
 return(NULL);
 }
 
@@ -1865,7 +1868,15 @@ if(xc->parallel_enabled)
         xc->section_header_only = 0;
         xc->secnum++;
 
+	while (xc->in_pthread)
+		{
+		pthread_mutex_lock(&xc->mutex);
+		pthread_mutex_unlock(&xc->mutex);
+		};
+
         pthread_mutex_lock(&xc->mutex);
+	xc->in_pthread = 1;
+        pthread_mutex_unlock(&xc->mutex);
 
         pthread_create(&xc->thread, &xc->thread_attr, fstWriterFlushContextPrivate1, xc2);
         }
@@ -1947,6 +1958,12 @@ if(xc && !xc->already_in_close && !xc->already_in_flush)
 #ifdef FST_WRITER_PARALLEL
                         pthread_mutex_lock(&xc->mutex);
                         pthread_mutex_unlock(&xc->mutex);
+
+			while (xc->in_pthread)
+				{
+				pthread_mutex_lock(&xc->mutex);
+				pthread_mutex_unlock(&xc->mutex);
+				};
 #endif
                         }
                 }
diff --git a/test_regress/driver.pl b/test_regress/driver.pl
index 0c5dc3851..d4b12ddb5 100755
--- a/test_regress/driver.pl
+++ b/test_regress/driver.pl
@@ -1076,15 +1076,6 @@ sub compile {
             return 1;
         }
 
-        if ($^O eq "freebsd") {
-            my $flags = join(' ', $self->compile_vlt_flags(%param));
-            if ($flags =~ /--trace-fst/ && $flags =~ /--trace-threads/) {
-                # See https://github.com/gtkwave/gtkwave/issues/24
-                $self->skip("Known fstapi.c threading issue on FreeBSD");
-                return 1;
-            }
-        }
-
         if (!$param{fails} && $param{make_main}) {
             $self->_make_main();
         }