From 059a6a89caabb86a31f7b97b76b2d408bdb2a442 Mon Sep 17 00:00:00 2001
From: Till Kamppeter <till.kamppeter@gmail.com>
Date: Sun, 20 Aug 2023 02:15:22 +0200
Subject: [PATCH] Added NULL checks for the functions dealing with dialogs

---
 src/backend_helper.c     | 17 ++++++++++-------
 src/print_backend_cups.c |  2 +-
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/src/backend_helper.c b/src/backend_helper.c
index 1b6201e..d2eab07 100644
--- a/src/backend_helper.c
+++ b/src/backend_helper.c
@@ -111,37 +111,37 @@ Dialog *find_dialog(BackendObj *b, const char *dialog_name)
 int *get_dialog_cancel(BackendObj *b, const char *dialog_name)
 {
     Dialog *d = (Dialog *)(g_hash_table_lookup(b->dialogs, dialog_name));
-    return &d->cancel;
+    return (d ? &d->cancel : NULL);
 }
 void set_dialog_cancel(BackendObj *b, const char *dialog_name)
 {
     int *x = get_dialog_cancel(b, dialog_name);
-    *x = 1;
+    if (x) *x = 1;
 }
 void reset_dialog_cancel(BackendObj *b, const char *dialog_name)
 {
     int *x = get_dialog_cancel(b, dialog_name);
-    *x = 0;
+    if (x) *x = 0;
 }
 void set_hide_remote_printers(BackendObj *b, const char *dialog_name)
 {
     Dialog *d = (Dialog *)(g_hash_table_lookup(b->dialogs, dialog_name));
-    d->hide_remote = TRUE;
+    if (d) d->hide_remote = TRUE;
 }
 void unset_hide_remote_printers(BackendObj *b, const char *dialog_name)
 {
     Dialog *d = (Dialog *)(g_hash_table_lookup(b->dialogs, dialog_name));
-    d->hide_remote = FALSE;
+    if (d) d->hide_remote = FALSE;
 }
 void set_hide_temp_printers(BackendObj *b, const char *dialog_name)
 {
     Dialog *d = (Dialog *)(g_hash_table_lookup(b->dialogs, dialog_name));
-    d->hide_temp = TRUE;
+    if (d) d->hide_temp = TRUE;
 }
 void unset_hide_temp_printers(BackendObj *b, const char *dialog_name)
 {
     Dialog *d = (Dialog *)(g_hash_table_lookup(b->dialogs, dialog_name));
-    d->hide_temp = FALSE;
+    if (d) d->hide_temp = FALSE;
 }
 
 static int
@@ -451,6 +451,7 @@ void send_printer_state_changed_signal(BackendObj *b, const char *dialog_name, c
 void notify_removed_printers(BackendObj *b, const char *dialog_name, GHashTable *new_table)
 {
     Dialog *d = (Dialog *)g_hash_table_lookup(b->dialogs, dialog_name);
+    if (!d) return;
 
     GHashTable *prev = d->printers;
     GList *prevlist = g_hash_table_get_keys(prev);
@@ -473,6 +474,8 @@ void notify_added_printers(BackendObj *b, const char *dialog_name, GHashTable *n
 {
     GHashTableIter iter;
     Dialog *d = (Dialog *)g_hash_table_lookup(b->dialogs, dialog_name);
+    if (!d) return;
+
     GHashTable *prev = d->printers;
     printf("Notifying added printers.\n");
     gpointer printer_name;
diff --git a/src/print_backend_cups.c b/src/print_backend_cups.c
index a1ea05e..12b04c6 100644
--- a/src/print_backend_cups.c
+++ b/src/print_backend_cups.c
@@ -293,7 +293,7 @@ static void on_stop_backend(GDBusConnection *connection,
      * Ignore this signal if the dialog's keep_alive variable is set
      */
     Dialog *d = find_dialog(b, sender_name);
-    if (d->keep_alive)
+    if (d && d->keep_alive)
         return;
 
     set_dialog_cancel(b, sender_name);