From 6b0dc184bf7c6b229915b98170db65c48e956dc0 Mon Sep 17 00:00:00 2001
From: Basil Crow <me@basilcrow.com>
Date: Wed, 24 Aug 2022 10:45:13 -0700
Subject: [PATCH] [JENKINS-67624] `FileAlreadyExistsException` on startup
 (#7027)

---
 core/src/main/java/hudson/Util.java | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/core/src/main/java/hudson/Util.java b/core/src/main/java/hudson/Util.java
index 51abbf86a1aa..2f88c274972e 100644
--- a/core/src/main/java/hudson/Util.java
+++ b/core/src/main/java/hudson/Util.java
@@ -1778,7 +1778,16 @@ public static Path createDirectories(@NonNull Path dir, FileAttribute<?>... attr
             if (Files.isDirectory(dir)) {
                 return dir;
             } else {
-                return Files.createDirectory(dir, attrs);
+                try {
+                    return Files.createDirectory(dir, attrs);
+                } catch (FileAlreadyExistsException e) {
+                    if (Files.isDirectory(dir)) {
+                        // a concurrent caller won the race
+                        return dir;
+                    } else {
+                        throw e;
+                    }
+                }
             }
         }
 
@@ -1786,7 +1795,15 @@ public static Path createDirectories(@NonNull Path dir, FileAttribute<?>... attr
         for (Path name : parent.relativize(dir)) {
             child = child.resolve(name);
             if (!Files.isDirectory(child)) {
-                Files.createDirectory(child, attrs);
+                try {
+                    Files.createDirectory(child, attrs);
+                } catch (FileAlreadyExistsException e) {
+                    if (Files.isDirectory(child)) {
+                        // a concurrent caller won the race
+                    } else {
+                        throw e;
+                    }
+                }
             }
         }