From 50b288aca324649fb5b357ce75972a5261cf94fc Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Mon, 1 Oct 2018 11:55:07 -0600
Subject: [PATCH] sandbox: Support file truncation with os_open()

At present files are not truncated on writing. This is a useful feature.
Add support for this.

Signed-off-by: Simon Glass <sjg@chromium.org>
---
 arch/sandbox/cpu/os.c | 2 ++
 include/os.h          | 1 +
 2 files changed, 3 insertions(+)

diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index d4d6d78dc7..1d87a53843 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -85,6 +85,8 @@ int os_open(const char *pathname, int os_flags)
 
 	if (os_flags & OS_O_CREAT)
 		flags |= O_CREAT;
+	if (os_flags & OS_O_TRUNC)
+		flags |= O_TRUNC;
 
 	return open(pathname, flags, 0777);
 }
diff --git a/include/os.h b/include/os.h
index 7116f87578..9e3a561b65 100644
--- a/include/os.h
+++ b/include/os.h
@@ -75,6 +75,7 @@ int os_open(const char *pathname, int flags);
 #define OS_O_RDWR	2
 #define OS_O_MASK	3	/* Mask for read/write flags */
 #define OS_O_CREAT	0100
+#define OS_O_TRUNC	01000
 
 /**
  * Access to the OS close() system call
-- 
2.39.5