gdb/nat/windows-nat.c

   1 /* Internal interfaces for the Windows code
   2    Copyright (C) 1995-2019 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 windows_thread_info::~windows_thread_info ()
  26 {
  27   CloseHandle (h);
  28 }
  29
  30 void
  31 windows_thread_info::suspend ()
  32 {
  33   if (suspended != 0)
  34     return;
  35
  36   if (SuspendThread (h) == (DWORD) -1)
  37     {
  38       DWORD err = GetLastError ();
  39
  40       /* We get Access Denied (5) when trying to suspend
  41          threads that Windows started on behalf of the
  42          debuggee, usually when those threads are just
  43          about to exit.
  44          We can get Invalid Handle (6) if the main thread
  45          has exited.  */
  46       if (err != ERROR_INVALID_HANDLE && err != ERROR_ACCESS_DENIED)
  47         warning (_("SuspendThread (tid=0x%x) failed. (winerr %u)"),
  48                  (unsigned) tid, (unsigned) err);
  49       suspended = -1;
  50     }
  51   else
  52     suspended = 1;
  53 }
  54
  55 void
  56 windows_thread_info::resume ()
  57 {
  58   if (suspended > 0)
  59     {
  60       stopped_at_software_breakpoint = false;
  61
  62       if (ResumeThread (h) == (DWORD) -1)
  63         {
  64           DWORD err = GetLastError ();
  65           warning (_("warning: ResumeThread (tid=0x%x) failed. (winerr %u)"),
  66                    (unsigned) tid, (unsigned) err);
  67         }
  68     }
  69   suspended = 0;
  70 }
  71
  72 const char *
  73 get_image_name (HANDLE h, void *address, int unicode)
  74 {
  75 #ifdef __CYGWIN__
  76   static char buf[MAX_PATH];
  77 #else
  78   static char buf[(2 * MAX_PATH) + 1];
  79 #endif
  80   DWORD size = unicode ? sizeof (WCHAR) : sizeof (char);
  81   char *address_ptr;
  82   int len = 0;
  83   char b[2];
  84   SIZE_T done;
  85
  86   /* Attempt to read the name of the dll that was detected.
  87      This is documented to work only when actively debugging
  88      a program.  It will not work for attached processes.  */
  89   if (address == NULL)
  90     return NULL;
  91
  92 #ifdef _WIN32_WCE
  93   /* Windows CE reports the address of the image name,
  94      instead of an address of a pointer into the image name.  */
  95   address_ptr = address;
  96 #else
  97   /* See if we could read the address of a string, and that the
  98      address isn't null.  */
  99   if (!ReadProcessMemory (h, address,  &address_ptr,
 100                           sizeof (address_ptr), &done)
 101       || done != sizeof (address_ptr)
 102       || !address_ptr)
 103     return NULL;
 104 #endif
 105
 106   /* Find the length of the string.  */
 107   while (ReadProcessMemory (h, address_ptr + len++ * size, &b, size, &done)
 108          && (b[0] != 0 || b[size - 1] != 0) && done == size)
 109     continue;
 110
 111   if (!unicode)
 112     ReadProcessMemory (h, address_ptr, buf, len, &done);
 113   else
 114     {
 115       WCHAR *unicode_address = (WCHAR *) alloca (len * sizeof (WCHAR));
 116       ReadProcessMemory (h, address_ptr, unicode_address, len * sizeof (WCHAR),
 117                          &done);
 118 #ifdef __CYGWIN__
 119       wcstombs (buf, unicode_address, MAX_PATH);
 120 #else
 121       WideCharToMultiByte (CP_ACP, 0, unicode_address, len, buf, sizeof buf,
 122                            0, 0);
 123 #endif
 124     }
 125
 126   return buf;
 127 }
 128
 129 }