Rationalise structure layout; add dirent.d_type field.

3 files changed, 215 insertions, 60 deletions

diff --git a/winsup/mingw/ChangeLog b/winsup/mingw/ChangeLog
index d8a9d4e..5f1e9a5 100644
--- a/winsup/mingw/ChangeLog
+++ b/winsup/mingw/ChangeLog
@@ -1,3 +1,29 @@
+2011-10-01  Keith Marshall  <keithmarshall@users.sourceforge.net>
+
+	Rationalise structure layout; add dirent.d_type field.
+
+	* include/dirent.h (struct dirent): Rearrange; add d_type field.
+	Add extra padding fields between d_type and d_name, to represent a
+	union with a _finddata_t struct, aligned at the d_type field.
+	(struct _wdirent): Likewise, with _wfinddata_t aligned at d_type.
+	(DT_REG, DT_DIR): New macros; define them to be equivalent to...
+	(_A_NORMAL, _A_SUBDIR): ...these Microsoft attributes respectively.
+	(DT_BLK, DT_CHR, DT_FIFO, DT_LNK, DT_SOCK): New macros; define them.
+	They have little relevance on Win32, so don't use them, substitute...
+	(DT_UNKNOWN): ...this new catch-all macro instead; define it.
+	(struct __dirstream_t): Change declaration; replace by opaque union.
+	(struct __wdirstream_t): Likewise.
+
+	* mingwex/dirent.c (struct __dirstream_t): Redefine as union; map...
+	(struct dirent, struct __dirstream_private_t): ...these to a common
+	address; the latter encapsulates the private data into...
+	(dd_private): ...this new member; update all references accordingly.
+	Adjust field layout to align with corresponding dirent fields.
+	(struct __wdirstream_t): Similarly redefine as union, mapping...
+	(struct _wdirent, struct __wdirstream_private_t): ...these.
+	(_treaddir): Set dirent.d_type to appropriate selection from...
+	(DT_REG, DT_DIR, DT_UNKNOWN): ...these.
+
 2011-08-27  Keith Marshall  <keithmarshall@users.sourceforge.net>
 
 	Don't expose implementation detail for opaque DIRENT structures.
@@ -3071,7 +3097,7 @@
 2002-09-17 Danny Smith <dannysmith@users.sourceforge.net>
 
 	* include/time.h (__need_NULL): Define before including
-	stddef.h. Thanks to: Rüdiger Dehmel <de@lmnet.de>.
+	stddef.h. Thanks to: Rüdiger Dehmel <de@lmnet.de>.
 
 2002-09-16 Ranjit Matthew <rmathew@hotmail.com>
 
diff --git a/winsup/mingw/include/dirent.h b/winsup/mingw/include/dirent.h
index 7d2af2b..3abedfa 100644
--- a/winsup/mingw/include/dirent.h
+++ b/winsup/mingw/include/dirent.h
@@ -24,6 +24,20 @@ struct dirent
 	long		d_ino;		/* Always zero. */
 	unsigned short	d_reclen;	/* Always zero. */
 	unsigned short	d_namlen;	/* Length of name in d_name. */
+
+	/* The following exactly mimic the layout of _finddata_t ...
+	 */
+	unsigned	d_type;		/* File attributes */
+	time_t		d_time_create;
+	time_t		d_time_access;	/* always midnight local time */
+	time_t		d_time_write;
+	_fsize_t	d_size;
+	/*
+	 * ...so that we may map a union of _finddata_t at the
+	 * location of d_type (corresponding to _finddata_t.attrib),
+	 * and thus map this directly to the _findfirst/_findnext
+	 * returned field.
+	 */
 	char		d_name[FILENAME_MAX]; /* File name. */
 };
 
@@ -31,7 +45,7 @@ struct dirent
  * This opaque data type represents the private structure
  * through which a directory stream is referenced.
  */
-typedef struct __dirstream_t DIR;
+typedef union __dirstream_t DIR;
 
 DIR* __cdecl __MINGW_NOTHROW opendir (const char*);
 struct dirent* __cdecl __MINGW_NOTHROW readdir (DIR*);
@@ -48,6 +62,20 @@ struct _wdirent
 	long		d_ino;		/* Always zero. */
 	unsigned short	d_reclen;	/* Always zero. */
 	unsigned short	d_namlen;	/* Length of name in d_name. */
+
+	/* The following exactly mimic the layout of _wfinddata_t ...
+	 */
+	unsigned	d_type;		/* File attributes */
+    	time_t		d_time_create;	/* -1 for FAT file systems */
+    	time_t		d_time_access;	/* -1 for FAT file systems */
+    	time_t		d_time_write;
+    	_fsize_t	d_size;
+	/*
+	 * ...so that we may map a union of _wfinddata_t at the
+	 * location of d_type (corresponding to _wfinddata_t.attrib),
+	 * and thus map this directly to the _wfindfirst/_wfindnext
+	 * returned field.
+	 */
 	wchar_t		d_name[FILENAME_MAX]; /* File name. */
 };
 
@@ -55,7 +83,7 @@ struct _wdirent
  * This opaque data type represents the private structure
  * through which a wide directory stream is referenced.
  */
-typedef struct __wdirstream_t _WDIR;
+typedef union __wdirstream_t _WDIR;
 
 _WDIR* __cdecl __MINGW_NOTHROW _wopendir (const wchar_t*);
 struct _wdirent*  __cdecl __MINGW_NOTHROW _wreaddir (_WDIR*);
@@ -69,6 +97,47 @@ void __cdecl __MINGW_NOTHROW _wseekdir (_WDIR*, long);
 }
 #endif
 
-#endif	/* Not RC_INVOKED */
+#if defined(_BSD_SOURCE) || defined(_WIN32)
+/*
+ * BSD-ish systems define manifest constants for the d_type field;
+ * although probably only DT_REG and DT_DIR are useful on Win32, we
+ * try to map them as best we can from the _finddata.attrib field.
+ *
+ * The relevant Microsoft manifest values are:
+ *
+ *   _A_NORMAL	(0x0000)	normal file: best fit for DT_REG
+ *   _A_RDONLY	(0x0001)	read-only: no BSD d_type equivalent
+ *   _A_HIDDEN	(0x0002)	hidden entity: no BSD equivalent
+ *   _A_SYSTEM	(0x0004)	system entity: no BSD equivalent
+ *   _A_VOLID	(0x0008)	volume label: no BSD equivalent
+ *   _A_SUBDIR	(0x0010)	directory: best fit for DT_DIR
+ *   _A_ARCH	(0x0020)	"dirty": no BSD equivalent
+ *
+ * Thus, we may immediately define:
+ */
+#define DT_REG   	_A_NORMAL
+#define DT_DIR   	_A_SUBDIR
+
+/* The remaining BSD d_type manifest values have no Win32 equivalents;
+ * we will define them artificially, and then we will ensure that our
+ * opendir()/readdir() implementation will never assign them; (we will
+ * substitute DT_UNKNOWN, but it would be unwise to simply make these
+ * equivalent to that, since an application is likely to simply check
+ * for d_type equal to any one of these defined types, and thus could
+ * mistakenly identify DT_UNKNOWN as being of the tested type):
+ */
+#define DT_BLK   	(((_A_SUBDIR) << 4) | DT_UNKNOWN)
+#define DT_CHR   	(((_A_SUBDIR) << 5) | DT_UNKNOWN)
+#define DT_FIFO  	(((_A_SUBDIR) << 6) | DT_UNKNOWN)
+#define DT_LNK   	(((_A_SUBDIR) << 7) | DT_UNKNOWN)
+#define DT_SOCK  	(((_A_SUBDIR) << 8) | DT_UNKNOWN)
+
+/* No file system entity can ever be simultaneously a volume label
+ * and a directory; we will exploit this to unambiguously define:
+ */
+#define DT_UNKNOWN	(_A_VOLID | _A_SUBDIR)
+
+#endif  /* _BSD_SOURCE */
+#endif	/* ! RC_INVOKED */
 
-#endif	/* Not _DIRENT_H_ */
+#endif	/* !defined _DIRENT_H_ */
diff --git a/winsup/mingw/mingwex/dirent.c b/winsup/mingw/mingwex/dirent.c
index 0d3e54a..f35a88d 100644
--- a/winsup/mingw/mingwex/dirent.c
+++ b/winsup/mingw/mingwex/dirent.c
@@ -28,23 +28,32 @@
 #define SUFFIX	_T("*")
 #define	SLASH	_T("\\")
 
-struct __dirstream_t
+union __dirstream_t
 {
   /* Actual (private) declaration for opaque data type "DIR". */
 
-    /* disk transfer area for this dir */
-    struct _finddata_t	dd_dta;
+  /* dirent struct to return from dir (NOTE: this makes this thread
+   * safe as long as only one thread uses a particular DIR struct at
+   * a time) */
+  struct dirent	dd_dir;
+
+  struct __dirstream_private_t
+  {
+    /* Three padding fields, matching the head of dd_dir...
+     */
+    long		dd_ino;		/* Always zero. */
+    unsigned short	dd_reclen;	/* Always zero. */
+    unsigned short	dd_namlen;	/* Length of name in d_name. */
 
-    /* dirent struct to return from dir (NOTE: this makes this thread
-     * safe as long as only one thread uses a particular DIR struct at
-     * a time) */
-    struct dirent	dd_dir;
+    /* ...to keep the start of this disk transfer area for this dir
+     * aligned at the offset of the dd_dir.d_type field
+     */
+    struct _finddata_t	dd_dta;
 
     /* _findnext handle */
     intptr_t		dd_handle;
 
-    /*
-     * Status of search:
+    /* Status of search:
      *   (type is now int -- was short in older versions).
      *   0 = not started yet (next entry to read is first entry)
      *  -1 = off the end
@@ -54,25 +63,36 @@ struct __dirstream_t
 
     /* given path for dir with search pattern (struct is extended) */
     char		dd_name[1];
+
+  } dd_private;
 };
 
-struct __wdirstream_t
+union __wdirstream_t
 {
   /* Actual (private) declaration for opaque data type "_WDIR". */
 
-    /* disk transfer area for this dir */
-    struct _wfinddata_t	dd_dta;
+  /* dirent struct to return from dir (NOTE: this makes this thread
+   * safe as long as only one thread uses a particular DIR struct at
+   * a time) */
+  struct _wdirent	dd_dir;
+
+  struct __wdirstream_private_t
+  {
+    /* Three padding fields, matching the head of dd_dir...
+     */
+    long		dd_ino;		/* Always zero. */
+    unsigned short	dd_reclen;	/* Always zero. */
+    unsigned short	dd_namlen;	/* Length of name in d_name. */
 
-    /* dirent struct to return from dir (NOTE: this makes this thread
-     * safe as long as only one thread uses a particular DIR struct at
-     * a time) */
-    struct _wdirent	dd_dir;
+    /* ...to keep the start of this disk transfer area for this dir
+     * aligned at the offset of the dd_dir.d_type field
+     */
+    struct _wfinddata_t	dd_dta;
 
     /* _findnext handle */
     intptr_t		dd_handle;
 
-    /*
-     * Status of search:
+    /* Status of search:
      *   0 = not started yet (next entry to read is first entry)
      *  -1 = off the end
      *   positive = 0 based index of next entry
@@ -81,8 +101,27 @@ struct __wdirstream_t
 
     /* given path for dir with search pattern (struct is extended) */
     wchar_t		dd_name[1];
+
+  } dd_private;
 };
 
+/* We map the BSD d_type field in the returned dirent structure
+ * from the Microsoft _finddata_t dd_dta.attrib bits, which are:
+ *
+ *   _A_NORMAL	(0x0000)	normal file: best fit for DT_REG
+ *   _A_RDONLY	(0x0001)	read-only: no BSD d_type equivalent
+ *   _A_HIDDEN	(0x0002)	hidden entity: no BSD equivalent
+ *   _A_SYSTEM	(0x0004)	system entity: no BSD equivalent
+ *   _A_VOLID	(0x0008)	volume label: no BSD equivalent
+ *   _A_SUBDIR	(0x0010)	directory: best fit for DT_DIR
+ *   _A_ARCH	(0x0020)	"dirty": no BSD equivalent
+ *
+ * Of these, _A_RDONLY, _A_HIDDEN, _A_SYSTEM, and _A_ARCH are
+ * modifier bits, rather than true entity type specifiers; we
+ * will ignore them in the mapping, by applying this mask:
+ */
+#define DT_IGNORED	(_A_RDONLY | _A_HIDDEN | _A_SYSTEM | _A_ARCH)
+
 /* Helper for opendir().  */
 static inline unsigned _tGetFileAttributes (const _TCHAR * tPath)
 {
@@ -161,27 +200,27 @@ _topendir (const _TCHAR *szPath)
     }
 
   /* Create the search expression. */
-  _tcscpy (nd->dd_name, szFullPath);
+  _tcscpy (nd->dd_private.dd_name, szFullPath);
 
   /* Add on a slash if the path does not end with one. */
-  if (nd->dd_name[0] != _T('\0')
-      && _tcsrchr (nd->dd_name, _T('/')) != nd->dd_name
-					    + _tcslen (nd->dd_name) - 1
-      && _tcsrchr (nd->dd_name, _T('\\')) != nd->dd_name
-      					     + _tcslen (nd->dd_name) - 1)
+  if (nd->dd_private.dd_name[0] != _T('\0')
+      && _tcsrchr (nd->dd_private.dd_name, _T('/')) != nd->dd_private.dd_name
+					    + _tcslen (nd->dd_private.dd_name) - 1
+      && _tcsrchr (nd->dd_private.dd_name, _T('\\')) != nd->dd_private.dd_name
+      					     + _tcslen (nd->dd_private.dd_name) - 1)
     {
-      _tcscat (nd->dd_name, SLASH);
+      _tcscat (nd->dd_private.dd_name, SLASH);
     }
 
   /* Add on the search pattern */
-  _tcscat (nd->dd_name, SUFFIX);
+  _tcscat (nd->dd_private.dd_name, SUFFIX);
 
   /* Initialize handle to -1 so that a premature closedir doesn't try
    * to call _findclose on it. */
-  nd->dd_handle = -1;
+  nd->dd_private.dd_handle = -1;
 
   /* Initialize the status. */
-  nd->dd_stat = 0;
+  nd->dd_private.dd_stat = 0;
 
   /* Initialize the dirent structure. ino and reclen are invalid under
    * Win32, and name simply points at the appropriate part of the
@@ -213,33 +252,33 @@ _treaddir (_TDIR * dirp)
       return (struct _tdirent *) 0;
     }
 
-  if (dirp->dd_stat < 0)
+  if (dirp->dd_private.dd_stat < 0)
     {
       /* We have already returned all files in the directory
        * (or the structure has an invalid dd_stat). */
       return (struct _tdirent *) 0;
     }
-  else if (dirp->dd_stat == 0)
+  else if (dirp->dd_private.dd_stat == 0)
     {
       /* We haven't started the search yet. */
       /* Start the search */
-      dirp->dd_handle = _tfindfirst (dirp->dd_name, &(dirp->dd_dta));
+      dirp->dd_private.dd_handle = _tfindfirst (dirp->dd_private.dd_name, &(dirp->dd_private.dd_dta));
 
-      if (dirp->dd_handle == -1)
+      if (dirp->dd_private.dd_handle == -1)
 	{
 	  /* Whoops! Seems there are no files in that
 	   * directory. */
-	  dirp->dd_stat = -1;
+	  dirp->dd_private.dd_stat = -1;
 	}
       else
 	{
-	  dirp->dd_stat = 1;
+	  dirp->dd_private.dd_stat = 1;
 	}
     }
   else
     {
       /* Get the next search entry. */
-      if (_tfindnext (dirp->dd_handle, &(dirp->dd_dta)))
+      if (_tfindnext (dirp->dd_private.dd_handle, &(dirp->dd_private.dd_dta)))
 	{
 	  /* We are off the end or otherwise error.	
 	     _findnext sets errno to ENOENT if no more file
@@ -247,25 +286,46 @@ _treaddir (_TDIR * dirp)
 	  DWORD winerr = GetLastError ();
 	  if (winerr == ERROR_NO_MORE_FILES)
 	    errno = 0;	
-	  _findclose (dirp->dd_handle);
-	  dirp->dd_handle = -1;
-	  dirp->dd_stat = -1;
+	  _findclose (dirp->dd_private.dd_handle);
+	  dirp->dd_private.dd_handle = -1;
+	  dirp->dd_private.dd_stat = -1;
 	}
       else
 	{
 	  /* Update the status to indicate the correct
 	   * number. */
-	  dirp->dd_stat++;
+	  dirp->dd_private.dd_stat++;
 	}
     }
 
-  if (dirp->dd_stat > 0)
+  if (dirp->dd_private.dd_stat > 0)
     {
       /* Successfully got an entry. Everything about the file is
        * already appropriately filled in except the length of the
-       * file name. */
-      dirp->dd_dir.d_namlen = _tcslen (dirp->dd_dta.name);
-      _tcscpy (dirp->dd_dir.d_name, dirp->dd_dta.name);
+       * file name...
+       */
+      dirp->dd_dir.d_namlen = _tcslen (dirp->dd_dir.d_name);
+      /*
+       * ...and the attributes returned in the dd_dta.attrib field;
+       * these require adjustment to their BSD equivalents, which are
+       * returned via the union with the dd_dir.d_type field:
+       */
+      switch( dirp->dd_dir.d_type &= ~DT_IGNORED )
+	{
+	  case DT_REG:
+	  case DT_DIR:
+	    /* After stripping out the modifier bits in DT_IGNORED,
+	     * (which we ALWAYS ignore), this pair require no further
+	     * adjustment...
+	     */
+	    break;
+
+	  default:
+	    /* ...while nothing else has an appropriate equivalent
+	     * in the BSD d_type identification model.
+	     */
+	    dirp->dd_dir.d_type = DT_UNKNOWN;
+	}
       return &dirp->dd_dir;
     }
 
@@ -292,9 +352,9 @@ _tclosedir (_TDIR * dirp)
       return -1;
     }
 
-  if (dirp->dd_handle != -1)
+  if (dirp->dd_private.dd_handle != -1)
     {
-      rc = _findclose (dirp->dd_handle);
+      rc = _findclose (dirp->dd_private.dd_handle);
     }
 
   /* Delete the dir structure. */
@@ -320,13 +380,13 @@ _trewinddir (_TDIR * dirp)
       return;
     }
 
-  if (dirp->dd_handle != -1)
+  if (dirp->dd_private.dd_handle != -1)
     {
-      _findclose (dirp->dd_handle);
+      _findclose (dirp->dd_private.dd_handle);
     }
 
-  dirp->dd_handle = -1;
-  dirp->dd_stat = 0;
+  dirp->dd_private.dd_handle = -1;
+  dirp->dd_private.dd_stat = 0;
 }
 
 /*
@@ -345,7 +405,7 @@ _ttelldir (_TDIR * dirp)
       errno = EFAULT;
       return -1;
     }
-  return dirp->dd_stat;
+  return dirp->dd_private.dd_stat;
 }
 
 /*
@@ -377,19 +437,19 @@ _tseekdir (_TDIR * dirp, long lPos)
   else if (lPos == -1)
     {
       /* Seek past end. */
-      if (dirp->dd_handle != -1)
+      if (dirp->dd_private.dd_handle != -1)
 	{
-	  _findclose (dirp->dd_handle);
+	  _findclose (dirp->dd_private.dd_handle);
 	}
-      dirp->dd_handle = -1;
-      dirp->dd_stat = -1;
+      dirp->dd_private.dd_handle = -1;
+      dirp->dd_private.dd_stat = -1;
     }
   else
     {
       /* Rewind and read forward to the appropriate index. */
       _trewinddir (dirp);
 
-      while ((dirp->dd_stat < lPos) && _treaddir (dirp))
+      while ((dirp->dd_private.dd_stat < lPos) && _treaddir (dirp))
 	;
     }
 }