From 78e81e514a46ebf758e766aca9de3811df518ab5 Mon Sep 17 00:00:00 2001
From: Evan Tschannen <evan.tschannen@snowflake.com>
Date: Fri, 19 Mar 2021 13:11:52 -0700
Subject: [PATCH] fix: OPEN_ATOMIC_WRITE_AND_CREATE did not create a new file
 handle for the replacement file, so when the disk queue calls replaceFile,
 truncates against the old file handle will happen on the new file resulting
 in corruption

---
 fdbrpc/sim2.actor.cpp | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/fdbrpc/sim2.actor.cpp b/fdbrpc/sim2.actor.cpp
index b169a62911..16b18ff00b 100644
--- a/fdbrpc/sim2.actor.cpp
+++ b/fdbrpc/sim2.actor.cpp
@@ -738,7 +738,6 @@ private:
 				    .detail("FileCount", machineCache.count(self->filename));
 				renameFile(sourceFilename.c_str(), self->filename.c_str());
 
-				ASSERT(!machineCache.count(self->filename));
 				machineCache[self->filename] = machineCache[sourceFilename];
 				machineCache.erase(sourceFilename);
 				self->actualFilename = self->filename;
@@ -2479,19 +2478,19 @@ Future<Reference<class IAsyncFile>> Sim2FileSystem::open(const std::string& file
 	if (flags & IAsyncFile::OPEN_UNCACHED) {
 		auto& machineCache = g_simulator.getCurrentProcess()->machine->openFiles;
 		std::string actualFilename = filename;
-		if (machineCache.find(filename) == machineCache.end()) {
-			if (flags & IAsyncFile::OPEN_ATOMIC_WRITE_AND_CREATE) {
-				actualFilename = filename + ".part";
-				auto partFile = machineCache.find(actualFilename);
-				if (partFile != machineCache.end()) {
-					Future<Reference<IAsyncFile>> f = AsyncFileDetachable::open(partFile->second);
-					if (FLOW_KNOBS->PAGE_WRITE_CHECKSUM_HISTORY > 0)
-						f = map(f, [=](Reference<IAsyncFile> r) {
-							return Reference<IAsyncFile>(new AsyncFileWriteChecker(r));
-						});
-					return f;
-				}
+		if (flags & IAsyncFile::OPEN_ATOMIC_WRITE_AND_CREATE) {
+			actualFilename = filename + ".part";
+			auto partFile = machineCache.find(actualFilename);
+			if (partFile != machineCache.end()) {
+				Future<Reference<IAsyncFile>> f = AsyncFileDetachable::open(partFile->second);
+				if (FLOW_KNOBS->PAGE_WRITE_CHECKSUM_HISTORY > 0)
+					f = map(f, [=](Reference<IAsyncFile> r) {
+						return Reference<IAsyncFile>(new AsyncFileWriteChecker(r));
+					});
+				return f;
 			}
+		}
+		if (machineCache.find(actualFilename) == machineCache.end()) {
 			// Simulated disk parameters are shared by the AsyncFileNonDurable and the underlying SimpleFile.
 			// This way, they can both keep up with the time to start the next operation
 			auto diskParameters =