gdb/nat/windows-nat.c

   1 /* Internal interfaces for the Windows code
   2    Copyright (C) 1995-2020 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "gdbsupport/common-defs.h"
  20 #include "nat/windows-nat.h"
  21
  22 namespace windows_nat
  23 {
  24
  25 HANDLE current_process_handle;
  26 DWORD current_process_id;
  27 DWORD main_thread_id;
  28 enum gdb_signal last_sig = GDB_SIGNAL_0;
  29 DEBUG_EVENT current_event;
  30 DEBUG_EVENT last_wait_event;
  31 windows_thread_info *current_windows_thread;
  32 DWORD desired_stop_thread_id = -1;
  33 std::vector<pending_stop> pending_stops;
  34 EXCEPTION_RECORD siginfo_er;
  35
  36 windows_thread_info::~windows_thread_info ()
  37 {
  38   CloseHandle (h);
  39 }
  40
  41 void
  42 windows_thread_info::suspend ()
  43 {
  44   if (suspended != 0)
  45     return;
  46
  47   if (SuspendThread (h) == (DWORD) -1)
  48     {
  49       DWORD err = GetLastError ();
  50
  51       /* We get Access Denied (5) when trying to suspend
  52          threads that Windows started on behalf of the
  53          debuggee, usually when those threads are just
  54          about to exit.
  55          We can get Invalid Handle (6) if the main thread
  56          has exited.  */
  57       if (err != ERROR_INVALID_HANDLE && err != ERROR_ACCESS_DENIED)
  58         warning (_("SuspendThread (tid=0x%x) failed. (winerr %u)"),
  59                  (unsigned) tid, (unsigned) err);
  60       suspended = -1;
  61     }
  62   else
  63     suspended = 1;
  64 }
  65
  66 void
  67 windows_thread_info::resume ()
  68 {
  69   if (suspended > 0)
  70     {
  71       stopped_at_software_breakpoint = false;
  72
  73       if (ResumeThread (h) == (DWORD) -1)
  74         {
  75           DWORD err = GetLastError ();
  76           warning (_("warning: ResumeThread (tid=0x%x) failed. (winerr %u)"),
  77                    (unsigned) tid, (unsigned) err);
  78         }
  79     }
  80   suspended = 0;
  81 }
  82
  83 const char *
  84 get_image_name (HANDLE h, void *address, int unicode)
  85 {
  86 #ifdef __CYGWIN__
  87   static char buf[MAX_PATH];
  88 #else
  89   static char buf[(2 * MAX_PATH) + 1];
  90 #endif
  91   DWORD size = unicode ? sizeof (WCHAR) : sizeof (char);
  92   char *address_ptr;
  93   int len = 0;
  94   char b[2];
  95   SIZE_T done;
  96
  97   /* Attempt to read the name of the dll that was detected.
  98      This is documented to work only when actively debugging
  99      a program.  It will not work for attached processes.  */
 100   if (address == NULL)
 101     return NULL;
 102
 103 #ifdef _WIN32_WCE
 104   /* Windows CE reports the address of the image name,
 105      instead of an address of a pointer into the image name.  */
 106   address_ptr = address;
 107 #else
 108   /* See if we could read the address of a string, and that the
 109      address isn't null.  */
 110   if (!ReadProcessMemory (h, address,  &address_ptr,
 111                           sizeof (address_ptr), &done)
 112       || done != sizeof (address_ptr)
 113       || !address_ptr)
 114     return NULL;
 115 #endif
 116
 117   /* Find the length of the string.  */
 118   while (ReadProcessMemory (h, address_ptr + len++ * size, &b, size, &done)
 119          && (b[0] != 0 || b[size - 1] != 0) && done == size)
 120     continue;
 121
 122   if (!unicode)
 123     ReadProcessMemory (h, address_ptr, buf, len, &done);
 124   else
 125     {
 126       WCHAR *unicode_address = (WCHAR *) alloca (len * sizeof (WCHAR));
 127       ReadProcessMemory (h, address_ptr, unicode_address, len * sizeof (WCHAR),
 128                          &done);
 129 #ifdef __CYGWIN__
 130       wcstombs (buf, unicode_address, MAX_PATH);
 131 #else
 132       WideCharToMultiByte (CP_ACP, 0, unicode_address, len, buf, sizeof buf,
 133                            0, 0);
 134 #endif
 135     }
 136
 137   return buf;
 138 }
 139
 140 }