From 5f85cb2f782c8c295cd2c41ff078fef99b5b5109 Mon Sep 17 00:00:00 2001
From: "bernard.xiong" <bernard.xiong@gmail.com>
Date: Fri, 29 Oct 2010 05:58:07 +0000
Subject: [PATCH] fix lseek issue.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1032 bbd45198-f89e-11dd-88c7-29a3b14d5316
---
 components/dfs/filesystems/elmfat/dfs_elm.c | 8 +++++++-
 components/dfs/filesystems/nfs/dfs_nfs.c    | 5 +++++
 components/dfs/src/dfs_file.c               | 9 ++++++++-
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/components/dfs/filesystems/elmfat/dfs_elm.c b/components/dfs/filesystems/elmfat/dfs_elm.c
index 0271fc72d..d798c5bbd 100644
--- a/components/dfs/filesystems/elmfat/dfs_elm.c
+++ b/components/dfs/filesystems/elmfat/dfs_elm.c
@@ -364,8 +364,9 @@ int dfs_elm_write(struct dfs_fd* file, const void* buf, rt_size_t len)
 	RT_ASSERT(fd != RT_NULL);
 
 	result = f_write(fd, buf, len, &byte_write);
-	/* update position */
+	/* update position and file size */
 	file->pos  = fd->fptr;
+	file->size = fd->fsize;
 	if (result == FR_OK) return byte_write;
 
 	return elm_result_to_dfs(result);
@@ -392,6 +393,11 @@ int dfs_elm_lseek(struct dfs_fd* file, rt_off_t offset)
 	RT_ASSERT(fd != RT_NULL);
 
 	result = f_lseek(fd, offset);
+	if (result == FR_OK)
+	{
+		/* return current position */
+		return fd->fptr;
+	}
 	return elm_result_to_dfs(result);
 }
 
diff --git a/components/dfs/filesystems/nfs/dfs_nfs.c b/components/dfs/filesystems/nfs/dfs_nfs.c
index a463b0dab..836f4f1d2 100644
--- a/components/dfs/filesystems/nfs/dfs_nfs.c
+++ b/components/dfs/filesystems/nfs/dfs_nfs.c
@@ -557,6 +557,8 @@ int nfs_read(struct dfs_fd* file, void *buf, rt_size_t count)
 		}
 		bytes=res.READ3res_u.resok.count;
 		fd->offset += bytes;
+		/* update current position */
+		file->pos = fd->offset;
 		memcpy(buf, res.READ3res_u.resok.data.data_val, bytes);
 	}
 	xdr_free((xdrproc_t)xdr_READ3res, (char *)&res);
@@ -606,6 +608,9 @@ int nfs_write(struct dfs_fd* file, const void *buf, rt_size_t count)
 	{
 		bytes=res.WRITE3res_u.resok.count;
 		fd->offset+=bytes;
+		/* update current position */
+		file->pos = fd->offset;
+		/* todo: update file size */
 	}
 	xdr_free((xdrproc_t)xdr_WRITE3res, (char *)&res);
 
diff --git a/components/dfs/src/dfs_file.c b/components/dfs/src/dfs_file.c
index 05b082e4a..a1b19941e 100644
--- a/components/dfs/src/dfs_file.c
+++ b/components/dfs/src/dfs_file.c
@@ -290,12 +290,19 @@ int dfs_file_flush(struct dfs_fd* fd)
  */
 int dfs_file_lseek(struct dfs_fd* fd, rt_off_t offset)
 {
+	int result;
 	struct dfs_filesystem* fs = fd->fs;
 
 	if (fd == RT_NULL) return -DFS_STATUS_EINVAL;
 	if (fs->ops->lseek == RT_NULL) return -DFS_STATUS_ENOSYS;
 
-	return fs->ops->lseek(fd, offset);
+	result = fs->ops->lseek(fd, offset);
+
+	/* update current position */
+	if (result >= 0)
+		fd->pos = result;
+
+	return result;
 }
 
 /**