2003-01-13 Andrew Cagney <ac131313@redhat.com>

[deliverable/binutils-gdb.git] / gdb / windows-nat.c

diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 8f9697a3f5835dbe278549f658f5f64c60d972dc..accd6847321ebe8cf2d014ed0354190d2c94ca93 100644 (file)
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1,6 +1,6 @@
 /* Target-vector operations for controlling win32 child processes, for GDB.
 
-   Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free
+   Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free
    Software Foundation, Inc.
 
    Contributed by Cygnus Solutions, A Red Hat Company.
@@ -1374,6 +1374,83 @@ has_detach_ability (void)
   return 0;
 }
 
+/* Try to set or remove a user privilege to the current process.  Return -1
+   if that fails, the previous setting of that privilege otherwise.
+
+   This code is copied from the Cygwin source code and rearranged to allow
+   dynamically loading of the needed symbols from advapi32 which is only
+   available on NT/2K/XP. */
+static int
+set_process_privilege (const char *privilege, BOOL enable)
+{
+  static HMODULE advapi32 = NULL;
+  static BOOL WINAPI (*OpenProcessToken)(HANDLE, DWORD, PHANDLE);
+  static BOOL WINAPI (*LookupPrivilegeValue)(LPCSTR, LPCSTR, PLUID);
+  static BOOL WINAPI (*AdjustTokenPrivileges)(HANDLE, BOOL, PTOKEN_PRIVILEGES,
+                                             DWORD, PTOKEN_PRIVILEGES, PDWORD);
+
+  HANDLE token_hdl = NULL;
+  LUID restore_priv;
+  TOKEN_PRIVILEGES new_priv, orig_priv;
+  int ret = -1;
+  DWORD size;
+
+  if (GetVersion () >= 0x80000000)  /* No security availbale on 9x/Me */
+    return 0;
+
+  if (!advapi32)
+    {
+      if (!(advapi32 = LoadLibrary ("advapi32.dll")))
+       goto out;
+      if (!OpenProcessToken)
+       OpenProcessToken = GetProcAddress (advapi32, "OpenProcessToken");
+      if (!LookupPrivilegeValue)
+       LookupPrivilegeValue = GetProcAddress (advapi32,
+                                              "LookupPrivilegeValueA");
+      if (!AdjustTokenPrivileges)
+       AdjustTokenPrivileges = GetProcAddress (advapi32,
+                                               "AdjustTokenPrivileges");
+      if (!OpenProcessToken || !LookupPrivilegeValue || !AdjustTokenPrivileges)
+        {
+         advapi32 = NULL;
+         goto out;
+       }
+    }
+  
+  if (!OpenProcessToken (GetCurrentProcess (),
+                        TOKEN_QUERY | TOKEN_ADJUST_PRIVILEGES,
+                        &token_hdl))
+    goto out;
+
+  if (!LookupPrivilegeValue (NULL, privilege, &restore_priv))
+    goto out;
+
+  new_priv.PrivilegeCount = 1;
+  new_priv.Privileges[0].Luid = restore_priv;
+  new_priv.Privileges[0].Attributes = enable ? SE_PRIVILEGE_ENABLED : 0;
+
+  if (!AdjustTokenPrivileges (token_hdl, FALSE, &new_priv,
+                              sizeof orig_priv, &orig_priv, &size))
+    goto out;
+#if 0
+  /* Disabled, otherwise every `attach' in an unprivileged user session
+     would raise the "Failed to get SE_DEBUG_NAME privilege" warning in
+     child_attach(). */
+  /* AdjustTokenPrivileges returns TRUE even if the privilege could not
+     be enabled. GetLastError () returns an correct error code, though. */
+  if (enable && GetLastError () == ERROR_NOT_ALL_ASSIGNED)
+    goto out;
+#endif
+
+  ret = orig_priv.Privileges[0].Attributes == SE_PRIVILEGE_ENABLED ? 1 : 0;
+
+out:
+  if (token_hdl)
+    CloseHandle (token_hdl);
+
+  return ret;
+}
+
 /* Attach to process PID, then initialize for debugging it.  */
 static void
 child_attach (char *args, int from_tty)
@@ -1384,8 +1461,15 @@ child_attach (char *args, int from_tty)
   if (!args)
     error_no_arg ("process-id to attach");
 
+  if (set_process_privilege (SE_DEBUG_NAME, TRUE) < 0)
+    {
+      printf_unfiltered ("Warning: Failed to get SE_DEBUG_NAME privilege\n");
+      printf_unfiltered ("This can cause attach to fail on Windows NT/2K/XP\n");
+    }
+
   pid = strtoul (args, 0, 0);
   ok = DebugActiveProcess (pid);
+  saw_create = 0;
 
   if (!ok)
     error ("Can't attach to process.");