From fa821be37b56798f70b488530a07adeb2092b69b Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Tue, 5 Jun 2001 09:21:39 +0000
Subject: [PATCH]         * fhandler.cc (fhandler_disk_file::fstat): Always
 reset file position         to original value after checking for executable
 magic.

---
 winsup/cygwin/ChangeLog   |  5 +++++
 winsup/cygwin/fhandler.cc | 23 +++++++++++++++--------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index c4cf3bb2d..3e15d5ee8 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+Tue Jun  5 11:18:00 2001  Corinna Vinschen <corinna@vinschen.de>
+
+	* fhandler.cc (fhandler_disk_file::fstat): Always reset file position
+	to original value after checking for executable magic.
+
 Mon Jun  4 16:21:00 2001  Corinna Vinschen <corinna@vinschen.de>
 
 	* cygheap.h (cygheap_user::cygheap_user): Initialize token to
diff --git a/winsup/cygwin/fhandler.cc b/winsup/cygwin/fhandler.cc
index 15e0e2303..5c613bccd 100644
--- a/winsup/cygwin/fhandler.cc
+++ b/winsup/cygwin/fhandler.cc
@@ -974,16 +974,23 @@ fhandler_disk_file::fstat (struct stat *buf)
 		buf->st_mode |= S_IFREG;
 		if (!dont_care_if_execable () && !get_execable_p ())
 		  {
-		    DWORD done;
+		    DWORD cur, done;
 		    char magic[3];
-		    /* FIXME should we use /etc/magic ? */
-		    magic[0] = magic[1] = magic[2] = '\0';
-		    if (ReadFile (get_handle (), magic, 3, &done, 0)
-			&& done == 3)
+
+		    /* First retrieve current position, set to beginning
+		       of file if not already there. */
+		    cur = SetFilePointer (get_handle(), 0, NULL, FILE_CURRENT);
+		    if (cur != INVALID_SET_FILE_POINTER &&
+		        (!cur ||
+			 SetFilePointer (get_handle(), 0, NULL, FILE_BEGIN)
+			 != INVALID_SET_FILE_POINTER))
 		      {
-			if (has_exec_chars (magic, done))
-			  set_execable_p ();
-			SetFilePointer (get_handle(), -(LONG) done, NULL, FILE_CURRENT);
+			/* FIXME should we use /etc/magic ? */
+			magic[0] = magic[1] = magic[2] = '\0';
+			if (ReadFile (get_handle (), magic, 3, &done, 0) &&
+			    done == 3 && has_exec_chars (magic, done))
+			    set_execable_p ();
+			SetFilePointer (get_handle(), cur, NULL, FILE_BEGIN);
 		      }
 		  }
 		if (get_execable_p ())