From 6a9ff287cddf1bee55c5d05331e0487372347151 Mon Sep 17 00:00:00 2001
From: Robert Fewell <14uBobIT@gmail.com>
Date: Sat, 14 Aug 2021 11:01:38 +0100
Subject: [PATCH] Wrap BillTermDecRef and TaxTableDecRef in test for shutdown

When Gnucash is shutting down, the TaxTables and BillTerms will be
destroyed/freed and may already have been so there is no point trying
to decrement a reference that is used to stop them being destroyed if
in use.
---
 libgnucash/engine/gncCustomer.c |  9 +++++----
 libgnucash/engine/gncEntry.c    | 12 ++++++++----
 libgnucash/engine/gncInvoice.c  | 10 +++++++---
 libgnucash/engine/gncVendor.c   | 11 +++++++----
 4 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/libgnucash/engine/gncCustomer.c b/libgnucash/engine/gncCustomer.c
index 2ce39c8cce..676a7ed4cc 100644
--- a/libgnucash/engine/gncCustomer.c
+++ b/libgnucash/engine/gncCustomer.c
@@ -358,11 +358,12 @@ static void gncCustomerFree (GncCustomer *cust)
     g_list_free (cust->jobs);
     g_free (cust->balance);
 
-    if (cust->terms)
-        gncBillTermDecRef (cust->terms);
-    if (cust->taxtable)
+    if (!qof_book_shutting_down (qof_instance_get_book (QOF_INSTANCE(cust))))
     {
-        gncTaxTableDecRef (cust->taxtable);
+        if (cust->terms)
+            gncBillTermDecRef (cust->terms);
+        if (cust->taxtable)
+            gncTaxTableDecRef (cust->taxtable);
     }
 
     /* qof_instance_release (&cust->inst); */
diff --git a/libgnucash/engine/gncEntry.c b/libgnucash/engine/gncEntry.c
index b967544638..9d813d2e57 100644
--- a/libgnucash/engine/gncEntry.c
+++ b/libgnucash/engine/gncEntry.c
@@ -462,10 +462,14 @@ static void gncEntryFree (GncEntry *entry)
         gncAccountValueDestroy (entry->i_tax_values);
     if (entry->b_tax_values)
         gncAccountValueDestroy (entry->b_tax_values);
-    if (entry->i_tax_table)
-        gncTaxTableDecRef (entry->i_tax_table);
-    if (entry->b_tax_table)
-        gncTaxTableDecRef (entry->b_tax_table);
+
+    if (!qof_book_shutting_down (qof_instance_get_book (QOF_INSTANCE(entry))))
+    {
+        if (entry->i_tax_table)
+            gncTaxTableDecRef (entry->i_tax_table);
+        if (entry->b_tax_table)
+            gncTaxTableDecRef (entry->b_tax_table);
+    }
 
     /* qof_instance_release (&entry->inst); */
     g_object_unref (entry);
diff --git a/libgnucash/engine/gncInvoice.c b/libgnucash/engine/gncInvoice.c
index 6ab155f813..ca9246136e 100644
--- a/libgnucash/engine/gncInvoice.c
+++ b/libgnucash/engine/gncInvoice.c
@@ -423,10 +423,14 @@ static void gncInvoiceFree (GncInvoice *invoice)
     g_list_free (invoice->entries);
     g_list_free (invoice->prices);
 
-    if (invoice->printname) g_free (invoice->printname);
+    if (invoice->printname)
+        g_free (invoice->printname);
 
-    if (invoice->terms)
-        gncBillTermDecRef (invoice->terms);
+    if (!qof_book_shutting_down (qof_instance_get_book (QOF_INSTANCE(invoice))))
+    {
+        if (invoice->terms)
+            gncBillTermDecRef (invoice->terms);
+    }
 
     /* qof_instance_release (&invoice->inst); */
     g_object_unref (invoice);
diff --git a/libgnucash/engine/gncVendor.c b/libgnucash/engine/gncVendor.c
index 50695de27d..1fa0a34100 100644
--- a/libgnucash/engine/gncVendor.c
+++ b/libgnucash/engine/gncVendor.c
@@ -501,10 +501,13 @@ static void gncVendorFree (GncVendor *vendor)
     g_list_free (vendor->jobs);
     g_free (vendor->balance);
 
-    if (vendor->terms)
-        gncBillTermDecRef (vendor->terms);
-    if (vendor->taxtable)
-        gncTaxTableDecRef (vendor->taxtable);
+    if (!qof_book_shutting_down (qof_instance_get_book (QOF_INSTANCE(vendor))))
+    {
+        if (vendor->terms)
+            gncBillTermDecRef (vendor->terms);
+        if (vendor->taxtable)
+            gncTaxTableDecRef (vendor->taxtable);
+    }
 
     /* qof_instance_release (&vendor->inst); */
     g_object_unref (vendor);