From 2e9fe498f27316f6b91ecf4540ca3c2c64f959c5 Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Tue, 21 Aug 2007 15:37:10 +0000
Subject: [PATCH] * fhandler_disk_file.cc (fhandler_base::fstat_helper):
Rewrite checking for executable file magic using a thread safe method
and re-enable this code.
---
winsup/cygwin/ChangeLog | 6 +++++
winsup/cygwin/fhandler_disk_file.cc | 38 ++++++++++++-----------------
2 files changed, 22 insertions(+), 22 deletions(-)
diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index f1caebe57..0db674fb9 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,9 @@
+2007-08-21 Corinna Vinschen <corinna@vinschen.de>
+
+ * fhandler_disk_file.cc (fhandler_base::fstat_helper): Rewrite checking
+ for executable file magic using a thread safe method and re-enable this
+ code.
+
2007-08-21 Corinna Vinschen <corinna@vinschen.de>
* syscalls.cc (unlink_nt): Drop one local FILE_BASIC_INFORMATION struct.
diff --git a/winsup/cygwin/fhandler_disk_file.cc b/winsup/cygwin/fhandler_disk_file.cc
index 164e9a0b2..c7c5d9f23 100644
--- a/winsup/cygwin/fhandler_disk_file.cc
+++ b/winsup/cygwin/fhandler_disk_file.cc
@@ -570,37 +570,31 @@ fhandler_base::fstat_helper (struct __stat64 *buf,
else
{
buf->st_mode |= S_IFREG;
-#if 0
- /* FIXME: Is this code really necessary? There are already
- two places in path_conv which look for executability.
- Also, by using the fhandler's io HANDLE, a stat call might
- change the file position for a short period of time in
- a not thread-safe way. */
if (pc.exec_state () == dont_know_if_executable)
{
- DWORD cur, done;
- LONG curhigh = 0;
- char magic[3];
+ UNICODE_STRING same;
+ OBJECT_ATTRIBUTES attr;
+ HANDLE h;
+ IO_STATUS_BLOCK io;
- /* First retrieve current position, set to beginning
- of file if not already there. */
- cur = SetFilePointer (get_handle (), 0, &curhigh, FILE_CURRENT);
- if ((cur != INVALID_SET_FILE_POINTER || GetLastError () == NO_ERROR)
- && ((!cur && !curhigh) || SetFilePointer (get_handle (), 0, NULL, FILE_BEGIN)
- != INVALID_SET_FILE_POINTER))
- {
- /* FIXME should we use /etc/magic ? */
- magic[0] = magic[1] = magic[2] = '\0';
- if (ReadFile (get_handle (), magic, 3, &done, NULL)
- && has_exec_chars (magic, done))
+ RtlInitUnicodeString (&same, L"");
+ InitializeObjectAttributes (&attr, &same, 0, get_handle (), NULL);
+ if (NT_SUCCESS (NtOpenFile (&h, FILE_READ_DATA, &attr, &io,
+ FILE_SHARE_VALID_FLAGS, 0)))
+ {
+ LARGE_INTEGER off = { QuadPart:0LL };
+ char magic[3];
+
+ if (NT_SUCCESS (NtReadFile (h, NULL, NULL, NULL, &io, magic,
+ 3, &off, NULL))
+ && has_exec_chars (magic, io.Information))
{
pc.set_exec ();
buf->st_mode |= STD_XBITS;
}
- SetFilePointer (get_handle (), cur, &curhigh, FILE_BEGIN);
+ NtClose (h);
}
}
-#endif
}
if (pc.exec_state () == is_executable)
buf->st_mode |= STD_XBITS;