From 8460c4ab52c14cb55c03bf44eeda210bf256cf3d Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sat, 15 Apr 2017 15:13:38 +0200
Subject: [PATCH] mescc: Add fsync.

* module/mes/libc-i386.mes (i386:fsync): New function.
  (i386:libc): Export it.
* mlibc.c (fsync): New function.
---
 mlibc.c                  | 18 ++++++++++++++++++
 module/mes/libc-i386.mes | 13 +++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/mlibc.c b/mlibc.c
index 562079b6..1e64cfb4 100644
--- a/mlibc.c
+++ b/mlibc.c
@@ -114,6 +114,24 @@ write (int fd, char const* s, int n)
        );
 }
 
+int
+fsync (int fd)
+{
+  int r;
+  //syscall (SYS_fsync, fd));
+  asm (
+       "mov %1,%%ebx\n\t"
+
+       "mov $0x76, %%eax\n\t"
+       "int $0x80\n\t"
+       "mov %%eax,%0\n\t"
+       : "=r" (r)
+       : "" (fd)
+       : "eax", "ebx"
+       );
+  return r;
+}
+
 void *
 brk (void *p)
 {
diff --git a/module/mes/libc-i386.mes b/module/mes/libc-i386.mes
index 1bc66129..b72a750b 100644
--- a/module/mes/libc-i386.mes
+++ b/module/mes/libc-i386.mes
@@ -92,6 +92,18 @@
     #xc3                                ; ret
     ))
 
+(define (i386:fsync f g ta t d)
+  '(
+    #x55                                ; push   %ebp
+    #x89 #xe5                           ; mov    %esp,%ebp
+
+    #x8b #x5d #x08                      ; mov    0x8(%ebp),%ebx
+    #xb8 #x76 #x00 #x00 #x00            ; mov    $0x76,%eax
+    #xcd #x80                           ; int    $0x80
+
+    #xc9                                ; leave
+    #xc3                                ; ret
+    ))
 
 (define (i386:_start)
  (string-append ".byte"
@@ -110,4 +122,5 @@
    (cons "open" (list i386:open))
    (cons "read" (list i386:read))
    (cons "write" (list i386:write))
+   (cons "fsync" (list i386:fsync))
    (cons "brk" (list i386:brk))))