From 7665d8b2f27a1662f31c4215afcfff325483fda0 Mon Sep 17 00:00:00 2001
From: Bron Gondwana <brong@fastmail.fm>
Date: Mon, 27 Jan 2025 11:22:13 +0100
Subject: [PATCH] icalvalue: return "" for NO_VALUE if
 ALLOW_EMPTY_PROPERTIES=true

---
 src/libical/icalproperty.c |  5 +++++
 src/libical/icalvalue.c    | 10 ++++++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/libical/icalproperty.c b/src/libical/icalproperty.c
index 36b7351b9..765cc4970 100644
--- a/src/libical/icalproperty.c
+++ b/src/libical/icalproperty.c
@@ -341,6 +341,11 @@ const char *icalproperty_as_ical_string(icalproperty *prop)
     char *buf;
 
     buf = icalproperty_as_ical_string_r(prop);
+#if ICAL_ALLOW_EMPTY_PROPERTIES
+    /* empty string is set to no-value, per commit b1a9eb33597028b2d160f289b6105f4aa67276a7
+     * which return NULL as the string value.  Convert back to an empty string here */
+    if (!buf) return "";
+#endif
     icalmemory_add_tmp_buffer(buf);
     return buf;
 }
diff --git a/src/libical/icalvalue.c b/src/libical/icalvalue.c
index 0f04eee92..305c7a604 100644
--- a/src/libical/icalvalue.c
+++ b/src/libical/icalvalue.c
@@ -1246,9 +1246,15 @@ char *icalvalue_as_ical_string_r(const icalvalue *value)
     case ICAL_NO_VALUE:
         _fallthrough();
 
-    default: {
+    default:
+#if ICAL_ALLOW_EMPTY_PROPERTIES
+        /* empty string is set to no-value, per
+         * commit b1a9eb33597028b2d160f289b6105f4aa67276a7
+         * Convert back to an empty string here */
+        return icalmemory_strdup("");
+#else
         return 0;
-    }
+#endif
     }
 }