From aec34ad6b30b2ee3fc19b8b7e0c6a3570235af4b Mon Sep 17 00:00:00 2001
From: Eddy Ashton <edashton@microsoft.com>
Date: Thu, 4 Jul 2024 09:39:30 +0000
Subject: [PATCH] Cleaner error when we can't open a new snapshot file

---
 src/host/snapshots.h | 30 +++++++++++++++++++-----------
 1 file changed, 19 insertions(+), 11 deletions(-)

diff --git a/src/host/snapshots.h b/src/host/snapshots.h
index 585d679c2587..b1f8906d4ea7 100644
--- a/src/host/snapshots.h
+++ b/src/host/snapshots.h
@@ -270,17 +270,25 @@ namespace asynchost
             {
               std::ofstream snapshot_file(
                 full_snapshot_path, std::ios::app | std::ios::binary);
-              const auto& snapshot = it->second.snapshot;
-              snapshot_file.write(
-                reinterpret_cast<const char*>(snapshot->data()),
-                snapshot->size());
-              snapshot_file.write(
-                reinterpret_cast<const char*>(receipt_data), receipt_size);
-
-              LOG_INFO_FMT(
-                "New snapshot file written to {} [{} bytes]",
-                file_name,
-                static_cast<size_t>(snapshot_file.tellp()));
+              if (!snapshot_file.good())
+              {
+                LOG_FAIL_FMT(
+                  "Cannot write snapshot: error opening file {}", file_name);
+              }
+              else
+              {
+                const auto& snapshot = it->second.snapshot;
+                snapshot_file.write(
+                  reinterpret_cast<const char*>(snapshot->data()),
+                  snapshot->size());
+                snapshot_file.write(
+                  reinterpret_cast<const char*>(receipt_data), receipt_size);
+
+                LOG_INFO_FMT(
+                  "New snapshot file written to {} [{} bytes]",
+                  file_name,
+                  static_cast<size_t>(snapshot_file.tellp()));
+              }
             }
 
             pending_snapshots.erase(it);