From 7083b0a4fa657bdce8cfaad25c13488b3a46de28 Mon Sep 17 00:00:00 2001
From: Bart Oldeman <bart@dosemu.org>
Date: Fri, 22 May 2009 00:25:11 +0000
Subject: [PATCH] On close or commit, only update those directory entry fields
 that have an SFT equivalent. The rest stays unmodified on disk.

git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1392 6ac86273-5f31-0410-b378-82cca8765d1b
---
 hdr/fat.h       |  1 +
 kernel/fatdir.c | 26 ++++++++++++++++++++++----
 kernel/fatfs.c  |  2 +-
 kernel/proto.h  |  3 ++-
 4 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/hdr/fat.h b/hdr/fat.h
index 8670bbc..bf4b6ca 100644
--- a/hdr/fat.h
+++ b/hdr/fat.h
@@ -145,6 +145,7 @@ BOOL checkdstart(struct dpb FAR *dpbp, struct dirent *dentry, CLUSTER value);
 #define DIR_EXT         FNAME_SIZE
 #define DIR_ATTRIB      (FNAME_SIZE+FEXT_SIZE)
 #define DIR_RESERVED    (FNAME_SIZE+FEXT_SIZE+1)
+#define DIR_START_HIGH  (FNAME_SIZE+FEXT_SIZE+9)
 #define DIR_TIME        (FNAME_SIZE+FEXT_SIZE+11)
 #define DIR_DATE        (FNAME_SIZE+FEXT_SIZE+13)
 #define DIR_START       (FNAME_SIZE+FEXT_SIZE+15)
diff --git a/kernel/fatdir.c b/kernel/fatdir.c
index 832b506..f4ce395 100644
--- a/kernel/fatdir.c
+++ b/kernel/fatdir.c
@@ -245,10 +245,10 @@ COUNT dir_read(REG f_node_ptr fnp)
  *  TRUE  - all OK.
  *  FALSE - error occured (fnode is released).
  */
-#ifndef IPL
-BOOL dir_write(REG f_node_ptr fnp)
+BOOL dir_write_update(REG f_node_ptr fnp, BOOL update)
 {
   struct buffer FAR *bp;
+  UBYTE FAR *vp;
 
   if (!(fnp->f_flags & F_DDIR))
     return FALSE;
@@ -272,7 +272,26 @@ BOOL dir_write(REG f_node_ptr fnp)
 
     swap_deleted(fnp->f_dir.dir_name);
 
-    putdirent(&fnp->f_dir, &bp->b_buffer[fnp->f_diridx * DIRENT_SIZE]);
+    vp = &bp->b_buffer[fnp->f_diridx * DIRENT_SIZE];
+
+    if (update)
+    {
+      /* only update fields that are also in the SFT, for dos_close/commit */
+      fmemcpy(&vp[DIR_NAME], fnp->f_dir.dir_name, FNAME_SIZE + FEXT_SIZE);
+      fputbyte(&vp[DIR_ATTRIB], fnp->f_dir.dir_attrib);
+      fputword(&vp[DIR_TIME], fnp->f_dir.dir_time);
+      fputword(&vp[DIR_DATE], fnp->f_dir.dir_date);
+      fputword(&vp[DIR_START], fnp->f_dir.dir_start);
+#ifdef WITHFAT32
+      if (ISFAT32(fnp->f_dpb))
+        fputword(&vp[DIR_START_HIGH], fnp->f_dir.dir_start_high);
+#endif
+      fputlong(&vp[DIR_SIZE], fnp->f_dir.dir_size);
+    }
+    else
+    {
+      putdirent(&fnp->f_dir, vp);
+    }
 
     swap_deleted(fnp->f_dir.dir_name);
 
@@ -281,7 +300,6 @@ BOOL dir_write(REG f_node_ptr fnp)
   }
   return TRUE;
 }
-#endif
 
 VOID dir_close(REG f_node_ptr fnp)
 {
diff --git a/kernel/fatfs.c b/kernel/fatfs.c
index 8ce34f1..d6c01ac 100644
--- a/kernel/fatfs.c
+++ b/kernel/fatfs.c
@@ -279,7 +279,7 @@ COUNT dos_close(COUNT fd)
   }
   fnp->f_flags |= F_DDIR;
 
-  dir_write(fnp);
+  dir_write_update(fnp, TRUE);
   dir_close(fnp);
   return SUCCESS;
 }
diff --git a/kernel/proto.h b/kernel/proto.h
index b685fd9..e455dd5 100644
--- a/kernel/proto.h
+++ b/kernel/proto.h
@@ -140,7 +140,8 @@ VOID fatal(BYTE * err_msg);
 VOID dir_init_fnode(f_node_ptr fnp, CLUSTER dirstart);
 f_node_ptr dir_open(const char *dirname, f_node_ptr fnp);
 COUNT dir_read(REG f_node_ptr fnp);
-BOOL dir_write(REG f_node_ptr fnp);
+BOOL dir_write_update(REG f_node_ptr fnp, BOOL update);
+#define dir_write(fnp) dir_write_update(fnp, FALSE)
 VOID dir_close(REG f_node_ptr fnp);
 COUNT dos_findfirst(UCOUNT attr, BYTE * name);
 COUNT dos_findnext(void);