Fix a FAT error when trying to create file in a non-existent directory. Reported by Andrew Tridgell.

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5764 42af7a65-404d-4744-a932-0658087f49c3

3 files changed, 48 insertions, 12 deletions

diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index b6b225c65..6baf9f235 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -4389,3 +4389,9 @@
 	  build different objects in the first and second pass kernel builds need
 	  to keep those objects in separate directories so that they are not
 	  constantly rebuilt (2013-93-19).
+	* fs/fat:  Create an error in FAT file creation.  The FAT logic was
+	  not making a distinction between directory non-existence and file
+	  non-existence so when it you try to create a file in a non-existent
+	  directory, it would create a file with the nameof the missing
+	  directory.  Reported by Andrew Tridgell.
+
diff --git a/nuttx/fs/fat/fs_fat32.c b/nuttx/fs/fat/fs_fat32.c
index 7202bb63d..c9167b3b4 100644
--- a/nuttx/fs/fat/fs_fat32.c
+++ b/nuttx/fs/fat/fs_fat32.c
@@ -260,6 +260,12 @@ static int fat_open(FAR struct file *filep, const char *relpath,
 
       /* fall through to finish the file open operations */
     }
+
+  /* ENOENT would be returned by fat_finddirentry() if the full
+   * directory path was found, but the file was not found in the
+   * final directory.
+   */
+ 
   else if (ret == -ENOENT)
     {
       /* The file does not exist.  Were we asked to create it? */
@@ -284,6 +290,9 @@ static int fat_open(FAR struct file *filep, const char *relpath,
       
       direntry = &fs->fs_buffer[dirinfo.fd_seq.ds_offset];
     }
+
+  /* No other error is handled */
+
   else
     {
       /* An error occurred while checking for file existence --
@@ -1406,6 +1415,7 @@ static int fat_opendir(struct inode *mountpt, const char *relpath, struct fs_dir
     {
       goto errout_with_semaphore;
     }
+
   direntry = &fs->fs_buffer[dirinfo.fd_seq.ds_offset];
 
   /* Check if this is the root directory */
@@ -1942,11 +1952,20 @@ static int fat_mkdir(struct inode *mountpt, const char *relpath, mode_t mode)
 
   ret = fat_finddirentry(fs, &dirinfo, relpath);
 
-  /* If anything exists at this location, then we fail with EEXIST */
+  /* Or if any error occurs other -ENOENT, then return the error.  For
+   * example, if one of the earlier directory path segments was not found
+   * then ENOTDIR will be returned.
+   */
 
-  if (ret == OK)
+  if (ret != -ENOENT)
     {
-      ret = -EEXIST;
+      /* If anything exists at this location, then we fail with EEXIST */
+
+      if (ret == OK)
+        {
+          ret = -EEXIST;
+        }
+
       goto errout_with_semaphore;
     }
 
@@ -2224,13 +2243,6 @@ int fat_rename(struct inode *mountpt, const char *oldrelpath,
   /* Now find the directory where we should create the newpath object */
 
   ret = fat_finddirentry(fs, &dirinfo, newrelpath);
-  if (ret == OK)
-    {
-      /* It is an error if the object at newrelpath already exists */
-
-      ret = -EEXIST;
-      goto errout_with_semaphore;
-    }
 
   /* What we expect is -ENOENT mean that the full directory path was
    * followed but that the object does not exists in the terminal directory.
@@ -2238,6 +2250,13 @@ int fat_rename(struct inode *mountpt, const char *oldrelpath,
 
   if (ret != -ENOENT)
     {
+      if (ret == OK)
+        {
+          /* It is an error if the object at newrelpath already exists */
+
+          ret = -EEXIST;
+        }
+
       goto errout_with_semaphore;
     }
 
diff --git a/nuttx/fs/fat/fs_fat32dirent.c b/nuttx/fs/fat/fs_fat32dirent.c
index 18cf67847..39bdb5371 100644
--- a/nuttx/fs/fat/fs_fat32dirent.c
+++ b/nuttx/fs/fat/fs_fat32dirent.c
@@ -2343,6 +2343,17 @@ int fat_finddirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo,
 
       if (ret < 0)
         {
+          /* A return value of -ENOENT would mean that the path segement
+           * was not found.  Let's distinguish to cases:  (1) the final
+           * file was not found in the directory (-ENOENT), or (2) one
+           * of the directory path segments does not exist (-ENOTDIR)
+           */
+
+          if (ret == -ENOENT && terminator != '\0')
+            {
+              return -ENOTDIR;
+            }
+
           return ret;
         }
 
@@ -2351,7 +2362,7 @@ int fat_finddirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo,
        * the path.
        */
 
-      if (!terminator)
+      if (terminator == '\0')
         {
           /* Return success meaning that the description the matching
            * directory entry is in dirinfo.
@@ -2795,7 +2806,7 @@ int fat_remove(struct fat_mountpt_s *fs, const char *relpath, bool directory)
   ret = fat_finddirentry(fs, &dirinfo, relpath);
   if (ret != OK)
     {
-      /* No such path */
+      /* Most likely, some element of the path does not exist. */
 
       return -ENOENT;
     }