Initial revision

1 files changed, 1122 insertions, 0 deletions

diff --git a/gdb/win32-nat.c b/gdb/win32-nat.c
new file mode 100644
index 00000000000..87e96bd23ac
--- /dev/null
+++ b/gdb/win32-nat.c
@@ -0,0 +1,1122 @@
+/* Target-vector operations for controlling win32 child processes, for GDB.
+   Copyright 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
+   Contributed by Cygnus Support.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without eve nthe implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+/* by Steve Chamberlain, sac@cygnus.com */
+
+/* We assume we're being built with and will be used for cygwin.  */
+
+#include "defs.h"
+#include "frame.h"		/* required by inferior.h */
+#include "inferior.h"
+#include "target.h"
+#include "wait.h"
+#include "gdbcore.h"
+#include "command.h"
+#include <signal.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <stdlib.h>
+
+#ifdef _MSC_VER
+#include "windefs.h"
+#else /* other WIN32 compiler */
+#include <windows.h>
+#endif
+
+#include "buildsym.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "gdb_string.h"
+#include "gdbthread.h"
+#include "gdbcmd.h"
+#include <sys/param.h>
+#include <unistd.h>
+
+/* The string sent by cygwin when it processes a signal.
+   FIXME: This should be in a cygwin include file. */
+#define CYGWIN_SIGNAL_STRING "cygwin: signal"
+
+#define CHECK(x) 	check (x, __FILE__,__LINE__)
+#define DEBUG_EXEC(x)	if (debug_exec)		printf x
+#define DEBUG_EVENTS(x)	if (debug_events)	printf x
+#define DEBUG_MEM(x)	if (debug_memory)	printf x
+#define DEBUG_EXCEPT(x)	if (debug_exceptions)	printf x
+
+/* Forward declaration */
+extern struct target_ops child_ops;
+
+static void child_stop PARAMS ((void));
+static int win32_child_thread_alive PARAMS ((int));
+
+static int last_sig = 0;	/* Set if a signal was received from the
+				   debugged process */
+
+/* Thread information structure used to track information that is
+   not available in gdb's thread structure. */
+typedef struct thread_info_struct
+{
+  struct thread_info_struct *next;
+  DWORD id;
+  HANDLE h;
+  char *name;
+  int suspend_count;
+  CONTEXT context;
+} thread_info;
+
+static thread_info thread_head = {NULL};
+
+/* The process and thread handles for the above context. */
+
+static DEBUG_EVENT current_event;	/* The current debug event from
+					   WaitForDebugEvent */
+static HANDLE current_process_handle;	/* Currently executing process */
+static thread_info *current_thread;	/* Info on currently selected thread */
+static DWORD main_thread_id;		/* Thread ID of the main thread */
+
+/* Counts of things. */
+static int exception_count = 0;
+static int event_count = 0;
+
+/* User options. */
+static int new_console = 0;
+static int new_group = 0;
+static int debug_exec = 0;		/* show execution */
+static int debug_events = 0;		/* show events from kernel */
+static int debug_memory = 0;		/* show target memory accesses */
+static int debug_exceptions = 0;	/* show target exceptions */
+
+/* This vector maps GDB's idea of a register's number into an address
+   in the win32 exception context vector.
+
+   It also contains the bit mask needed to load the register in question.
+
+   One day we could read a reg, we could inspect the context we
+   already have loaded, if it doesn't have the bit set that we need,
+   we read that set of registers in using GetThreadContext.  If the
+   context already contains what we need, we just unpack it. Then to
+   write a register, first we have to ensure that the context contains
+   the other regs of the group, and then we copy the info in and set
+   out bit. */
+
+#define context_offset(x) ((int)&(((CONTEXT *)NULL)->x))
+static const int mappings[] =
+{
+  context_offset(Eax),
+  context_offset(Ecx),
+  context_offset(Edx),
+  context_offset(Ebx),
+  context_offset(Esp),
+  context_offset(Ebp),
+  context_offset(Esi),
+  context_offset(Edi),
+  context_offset(Eip),
+  context_offset(EFlags),
+  context_offset(SegCs),
+  context_offset(SegSs),
+  context_offset(SegDs),
+  context_offset(SegEs),
+  context_offset(SegFs),
+  context_offset(SegGs),
+  context_offset(FloatSave.RegisterArea[0 * 10]),
+  context_offset(FloatSave.RegisterArea[1 * 10]),
+  context_offset(FloatSave.RegisterArea[2 * 10]),
+  context_offset(FloatSave.RegisterArea[3 * 10]),
+  context_offset(FloatSave.RegisterArea[4 * 10]),
+  context_offset(FloatSave.RegisterArea[5 * 10]),
+  context_offset(FloatSave.RegisterArea[6 * 10]),
+  context_offset(FloatSave.RegisterArea[7 * 10]),
+};
+
+/* This vector maps the target's idea of an exception (extracted
+   from the DEBUG_EVENT structure) to GDB's idea. */
+
+struct xlate_exception
+  {
+    int them;
+    enum target_signal us;
+  };
+
+static const struct xlate_exception
+  xlate[] =
+{
+  {EXCEPTION_ACCESS_VIOLATION, TARGET_SIGNAL_SEGV},
+  {STATUS_STACK_OVERFLOW, TARGET_SIGNAL_SEGV},
+  {EXCEPTION_BREAKPOINT, TARGET_SIGNAL_TRAP},
+  {DBG_CONTROL_C, TARGET_SIGNAL_INT},
+  {EXCEPTION_SINGLE_STEP, TARGET_SIGNAL_TRAP},
+  {-1, -1}};
+
+/* Find a thread record given a thread id.
+   If get_context then also retrieve the context for this
+   thread. */
+static thread_info *
+thread_rec (DWORD id, int get_context)
+{
+  thread_info *th;
+
+  for (th = &thread_head; (th = th->next) != NULL; )
+    if (th->id == id)
+      {
+	if (!th->suspend_count && get_context)
+	  {
+	    if (get_context > 0)
+	      th->suspend_count = SuspendThread (th->h) + 1;
+	    else if (get_context < 0)
+	      th->suspend_count = -1;
+
+	    th->context.ContextFlags = CONTEXT_DEBUGGER;
+	    GetThreadContext (th->h, &th->context);
+	  }
+	return th;
+      }
+
+  return NULL;
+}
+
+/* Add a thread to the thread list */
+static thread_info *
+child_add_thread(DWORD id, HANDLE h)
+{
+  thread_info *th;
+
+  if ((th = thread_rec (id, FALSE)))
+    return th;
+
+  th = (thread_info *) xmalloc (sizeof (*th));
+  memset(th, 0, sizeof (*th));
+  th->id = id;
+  th->h = h;
+  th->next = thread_head.next;
+  thread_head.next = th;
+  add_thread (id);
+  return th;
+}
+
+/* Clear out any old thread list and reintialize it to a
+   pristine state. */
+static void
+child_init_thread_list ()
+{
+  thread_info *th = &thread_head;
+
+  DEBUG_EVENTS (("gdb: child_init_thread_list\n"));
+  init_thread_list ();
+  while (th->next != NULL)
+    {
+      thread_info *here = th->next;
+      th->next = here->next;
+      (void) CloseHandle (here->h);
+      free (here);
+    }
+}
+
+/* Delete a thread from the list of threads */
+static void
+child_delete_thread (DWORD id)
+{
+  thread_info *th;
+
+  if (info_verbose)
+    printf_unfiltered ("[Deleting %s]\n", target_pid_to_str (id));
+  delete_thread (id);
+
+  for (th = &thread_head;
+       th->next != NULL && th->next->id != id;
+       th = th->next)
+    continue;
+
+  if (th->next != NULL)
+    {
+      thread_info *here = th->next;
+      th->next = here->next;
+      CloseHandle (here->h);
+      free (here);
+    }
+}
+
+static void
+check (BOOL ok, const char *file, int line)
+{
+  if (!ok)
+    printf_filtered ("error return %s:%d was %d\n", file, line, GetLastError ());
+}
+
+static void
+do_child_fetch_inferior_registers (int r)
+{
+  if (r >= 0)
+    supply_register (r, ((char *) &current_thread->context) + mappings[r]);
+  else
+    {
+      for (r = 0; r < NUM_REGS; r++)
+	do_child_fetch_inferior_registers (r);
+    }
+}
+
+static void
+child_fetch_inferior_registers (int r)
+{
+  current_thread = thread_rec (inferior_pid, TRUE);
+  do_child_fetch_inferior_registers (r);
+}
+
+static void
+do_child_store_inferior_registers (int r)
+{
+  if (r >= 0)
+    read_register_gen (r, ((char *) &current_thread->context) + mappings[r]);
+  else
+    {
+      for (r = 0; r < NUM_REGS; r++)
+	do_child_store_inferior_registers (r);
+    }
+}
+
+/* Store a new register value into the current thread context */
+static void
+child_store_inferior_registers (int r)
+{
+  current_thread = thread_rec (inferior_pid, TRUE);
+  do_child_store_inferior_registers (r);
+}
+
+/* Wait for child to do something.  Return pid of child, or -1 in case
+   of error; store status through argument pointer OURSTATUS.  */
+
+static int
+handle_load_dll (PTR dummy)
+{
+  LOAD_DLL_DEBUG_INFO * event = &current_event.u.LoadDll;
+  DWORD dll_name_ptr;
+  DWORD done;
+  char dll_buf[MAX_PATH + 1];
+  char *p, *dll_name = NULL, *dll_basename;
+  struct objfile *objfile;
+  MEMORY_BASIC_INFORMATION minfo;
+
+  dll_buf[0] = dll_buf[sizeof(dll_buf) - 1] = '\0';
+
+  /* The following code attempts to find the name of the dll by reading the
+     name from the processes memory.  Unfortunately it doesn't work right.
+     Doing this the "right way" for Windows is very difficult.  FIXME */
+#ifdef DOESNT_WORK
+  memset (&minfo, 0, sizeof minfo);
+  if (VirtualQueryEx (current_process_handle, (LPCVOID) event->lpBaseOfDll,
+		      &minfo, sizeof(minfo)) && minfo.BaseAddress) {
+      DWORD len;
+      IMAGE_DOS_HEADER *hmm0 = (IMAGE_DOS_HEADER *) minfo.BaseAddress;
+      HMODULE hmm = (HMODULE) (((DWORD) hmm0) + hmm0->e_lfanew);
+
+      if ((len = GetModuleFileName (hmm, dll_buf, MAX_PATH)))
+	{
+	  dll_name = dll_buf;
+	  dll_name[len] = '\0';
+	}
+  }
+#endif
+
+  /* Attempt to read the name of the dll that was detected.
+     This is documented to work only when actively debugging
+     a program.  It will not work for attached processes. */
+  if (dll_name == NULL || *dll_name == '\0')
+    {
+      int size = event->fUnicode ? sizeof (WCHAR) : sizeof (char);
+      int len = 0;
+      char b[2];
+
+      ReadProcessMemory (current_process_handle,
+			 (LPCVOID) event->lpImageName,
+			 (char *) &dll_name_ptr,
+			 sizeof (dll_name_ptr), &done);
+
+      /* See if we could read the address of a string, and that the
+	 address isn't null. */
+
+      if (done != sizeof (dll_name_ptr) || !dll_name_ptr)
+	return 1;
+
+      do
+	{
+	  ReadProcessMemory (current_process_handle,
+			     (LPCVOID) (dll_name_ptr + len * size),
+			     &b,
+			     size,
+			     &done);
+	  len++;
+	}
+      while ((b[0] != 0 || b[size - 1] != 0) && done == size);
+
+      dll_name = alloca (len);
+
+      if (event->fUnicode)
+	{
+	  WCHAR *unicode_dll_name = (WCHAR *) alloca (len * sizeof (WCHAR));
+	  ReadProcessMemory (current_process_handle,
+			     (LPCVOID) dll_name_ptr,
+			     unicode_dll_name,
+			     len * sizeof (WCHAR),
+			     &done);
+
+	  WideCharToMultiByte (CP_ACP, 0,
+			       unicode_dll_name, len,
+			       dll_name, len, 0, 0);
+	}
+      else
+	{
+	  ReadProcessMemory (current_process_handle,
+			     (LPCVOID) dll_name_ptr,
+			     dll_name,
+			     len,
+			     &done);
+	}
+    }
+
+  if (!dll_name)
+    return 1;
+
+  while ((p = strchr (dll_name, '\\')))
+    *p = '/';
+
+  /* FIXME!! It would be nice to define one symbol which pointed to the
+     front of the dll if we can't find any symbols. */
+
+  if (!(dll_basename = strrchr(dll_name, '/')))
+    dll_basename = dll_name;
+  else
+    dll_basename++;
+
+  ALL_OBJFILES(objfile)
+    {
+      char *objfile_basename;
+      objfile_basename = strrchr(objfile->name, '/');
+
+      if (objfile_basename &&
+	  strcmp(dll_basename, objfile_basename + 1) == 0)
+	{
+	  printf_unfiltered ("%x:%s (symbols previously loaded)\n",
+			     event->lpBaseOfDll, dll_name);
+	  goto out;
+	}
+  }
+
+  /* The symbols in a dll are offset by 0x1000, which is the
+     the offset from 0 of the first byte in an image - because
+     of the file header and the section alignment.
+
+     FIXME: Is this the real reason that we need the 0x1000 ? */
+
+  printf_unfiltered ("%x:%s", event->lpBaseOfDll, dll_name);
+  symbol_file_add (dll_name, 0, (int) event->lpBaseOfDll + 0x1000, 0, 0, 0, 0, 1);
+  printf_unfiltered ("\n");
+
+out:
+  return 1;
+}
+
+/* Handle DEBUG_STRING output from child process.
+   Cygwin prepends its messages with a "cygwin:".  Interpret this as
+   a Cygwin signal.  Otherwise just print the string as a warning. */
+static int
+handle_output_debug_string (struct target_waitstatus *ourstatus)
+{
+  char *s;
+  int gotasig = FALSE;
+
+  if (!target_read_string
+      ((CORE_ADDR) current_event.u.DebugString.lpDebugStringData, &s, 1024, 0)
+      || !s || !*s)
+    return gotasig;
+
+  if (strncmp(s, CYGWIN_SIGNAL_STRING, sizeof(CYGWIN_SIGNAL_STRING) - 1))
+    {
+      warning (s);
+    }
+  else
+    {
+      char *p;
+      /*last_sig = */strtol(s + sizeof(CYGWIN_SIGNAL_STRING) - 1, &p, 0);
+      if (gotasig = (ourstatus->value.sig = target_signal_from_host (last_sig)))
+	ourstatus->kind = TARGET_WAITKIND_STOPPED;
+    }
+
+  free (s);
+  return gotasig;
+}
+
+static int
+handle_exception (struct target_waitstatus *ourstatus)
+{
+  int i;
+  int done = 0;
+  thread_info *th;
+
+  ourstatus->kind = TARGET_WAITKIND_STOPPED;
+
+  /* Record the context of the current thread */
+  th = thread_rec (current_event.dwThreadId, -1);
+
+  switch (current_event.u.Exception.ExceptionRecord.ExceptionCode)
+    {
+    case EXCEPTION_ACCESS_VIOLATION:
+      DEBUG_EXCEPT (("gdb: Target exception ACCESS_VIOLATION at 0x%08x\n",
+		     current_event.u.Exception.ExceptionRecord.ExceptionAddress));
+      ourstatus->value.sig = TARGET_SIGNAL_SEGV;
+      break;
+    case STATUS_STACK_OVERFLOW:
+      DEBUG_EXCEPT (("gdb: Target exception STACK_OVERFLOW at 0x%08x\n",
+		     current_event.u.Exception.ExceptionRecord.ExceptionAddress));
+      ourstatus->value.sig = TARGET_SIGNAL_SEGV;
+      break;
+    case EXCEPTION_BREAKPOINT:
+      DEBUG_EXCEPT (("gdb: Target exception BREAKPOINT at 0x%08x\n",
+		     current_event.u.Exception.ExceptionRecord.ExceptionAddress));
+      ourstatus->value.sig = TARGET_SIGNAL_TRAP;
+      break;
+    case DBG_CONTROL_C:
+      DEBUG_EXCEPT (("gdb: Target exception CONTROL_C at 0x%08x\n",
+		     current_event.u.Exception.ExceptionRecord.ExceptionAddress));
+      ourstatus->value.sig = TARGET_SIGNAL_INT;
+      /* User typed CTRL-C.  Continue with this status */
+      last_sig = SIGINT;	/* FIXME - should check pass state */
+      break;
+    case EXCEPTION_SINGLE_STEP:
+      DEBUG_EXCEPT (("gdb: Target exception SINGLE_STEP at 0x%08x\n",
+		     current_event.u.Exception.ExceptionRecord.ExceptionAddress));
+      ourstatus->value.sig = TARGET_SIGNAL_TRAP;
+      break;
+    default:
+      /* This may be a structured exception handling exception.  In
+	 that case, we want to let the program try to handle it, and
+	 only break if we see the exception a second time.  */
+      if (current_event.u.Exception.dwFirstChance)
+	return 0;
+
+      printf_unfiltered ("gdb: unknown target exception 0x%08x at 0x%08x\n",
+			 current_event.u.Exception.ExceptionRecord.ExceptionCode,
+			 current_event.u.Exception.ExceptionRecord.ExceptionAddress);
+      ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
+      break;
+    }
+  exception_count++;
+  return 1;
+}
+
+/* Resume all artificially suspended threads if we are continuing
+   execution */
+static BOOL
+child_continue (DWORD continue_status, int id)
+{
+  int i;
+  thread_info *th;
+  BOOL res;
+
+  DEBUG_EVENTS (("ContinueDebugEvent (cpid=%d, ctid=%d, DBG_CONTINUE);\n",
+		 current_event.dwProcessId, current_event.dwThreadId));
+  if (res = ContinueDebugEvent (current_event.dwProcessId,
+				current_event.dwThreadId,
+			        continue_status))
+    for (th = &thread_head; (th = th->next) != NULL; )
+      if (((id == -1) || (id == th->id)) && th->suspend_count)
+	{
+	  for (i = 0; i < th->suspend_count; i++)
+	    (void) ResumeThread (th->h);
+	  th->suspend_count = 0;
+	}
+
+  return res;
+}
+
+static int
+child_wait (int pid, struct target_waitstatus *ourstatus)
+{
+  /* We loop when we get a non-standard exception rather than return
+     with a SPURIOUS because resume can try and step or modify things,
+     which needs a current_thread->h.  But some of these exceptions mark
+     the birth or death of threads, which mean that the current thread
+     isn't necessarily what you think it is. */
+
+  while (1)
+    {
+      DWORD continue_status;
+      BOOL t = WaitForDebugEvent (&current_event, INFINITE);
+      char *p;
+      thread_info *th;
+      int sig;
+
+      event_count++;
+
+      continue_status = DBG_CONTINUE;
+
+      switch (current_event.dwDebugEventCode)
+	{
+	case CREATE_THREAD_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%x code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"CREATE_THREAD_DEBUG_EVENT"));
+	  /* Record the existence of this thread */
+	  child_add_thread (current_event.dwThreadId,
+			    current_event.u.CreateThread.hThread);
+	  if (info_verbose)
+	      printf_unfiltered ("[New %s]\n",
+			       target_pid_to_str (current_event.dwThreadId));
+	  break;
+
+	case EXIT_THREAD_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"EXIT_THREAD_DEBUG_EVENT"));
+	  child_delete_thread (current_event.dwThreadId);
+	  break;
+
+	case CREATE_PROCESS_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"CREATE_PROCESS_DEBUG_EVENT"));
+	  current_process_handle = current_event.u.CreateProcessInfo.hProcess;
+
+	  main_thread_id = inferior_pid = current_event.dwThreadId;
+	  /* Add the main thread */
+	  current_thread = child_add_thread (inferior_pid,
+				current_event.u.CreateProcessInfo.hThread);
+	  break;
+
+	case EXIT_PROCESS_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"EXIT_PROCESS_DEBUG_EVENT"));
+	  ourstatus->kind = TARGET_WAITKIND_EXITED;
+	  ourstatus->value.integer = current_event.u.ExitProcess.dwExitCode;
+	  CloseHandle (current_process_handle);
+	  return current_event.dwProcessId;
+	  break;
+
+	case LOAD_DLL_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"LOAD_DLL_DEBUG_EVENT"));
+          catch_errors (handle_load_dll, NULL, "", RETURN_MASK_ALL);
+	  registers_changed();          /* mark all regs invalid */
+	  break;
+
+	case UNLOAD_DLL_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"UNLOAD_DLL_DEBUG_EVENT"));
+	  break;	/* FIXME: don't know what to do here */
+
+	case EXCEPTION_DEBUG_EVENT:
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"EXCEPTION_DEBUG_EVENT"));
+	  if (handle_exception (ourstatus))
+	    return current_event.dwThreadId;
+	  continue_status = DBG_EXCEPTION_NOT_HANDLED;
+	  break;
+
+	case OUTPUT_DEBUG_STRING_EVENT: /* message from the kernel */
+	  DEBUG_EVENTS (("gdb: kernel event for pid=%d tid=%d code=%s)\n",
+			current_event.dwProcessId, current_event.dwThreadId,
+			"OUTPUT_DEBUG_STRING_EVENT"));
+	  if (handle_output_debug_string (ourstatus))
+	    return main_thread_id;
+	  break;
+	default:
+	  printf_unfiltered ("gdb: kernel event for pid=%d tid=%d\n",
+			     current_event.dwProcessId,
+			     current_event.dwThreadId);
+	  printf_unfiltered ("                 unknown event code %d\n",
+			     current_event.dwDebugEventCode);
+	  break;
+	}
+
+      CHECK (child_continue (continue_status, -1));
+    }
+}
+
+/* Attach to process PID, then initialize for debugging it.  */
+
+static void
+child_attach (args, from_tty)
+     char *args;
+     int from_tty;
+{
+  BOOL ok;
+
+  if (!args)
+    error_no_arg ("process-id to attach");
+
+  current_event.dwProcessId = strtoul (args, 0, 0);
+
+  ok = DebugActiveProcess (current_event.dwProcessId);
+
+  if (!ok)
+    error ("Can't attach to process.");
+
+  exception_count = 0;
+  event_count = 0;
+
+  if (from_tty)
+    {
+      char *exec_file = (char *) get_exec_file (0);
+
+      if (exec_file)
+	printf_unfiltered ("Attaching to program `%s', %s\n", exec_file,
+			   target_pid_to_str (current_event.dwProcessId));
+      else
+	printf_unfiltered ("Attaching to %s\n",
+			   target_pid_to_str (current_event.dwProcessId));
+
+      gdb_flush (gdb_stdout);
+    }
+
+  push_target (&child_ops);
+}
+
+static void
+child_detach (args, from_tty)
+     char *args;
+     int from_tty;
+{
+  if (from_tty)
+    {
+      char *exec_file = get_exec_file (0);
+      if (exec_file == 0)
+	exec_file = "";
+      printf_unfiltered ("Detaching from program: %s %s\n", exec_file,
+			 target_pid_to_str (inferior_pid));
+      gdb_flush (gdb_stdout);
+    }
+  inferior_pid = 0;
+  unpush_target (&child_ops);
+}
+
+/* Print status information about what we're accessing.  */
+
+static void
+child_files_info (ignore)
+     struct target_ops *ignore;
+{
+  printf_unfiltered ("\tUsing the running image of %s %s.\n",
+      attach_flag ? "attached" : "child", target_pid_to_str (inferior_pid));
+}
+
+/* ARGSUSED */
+static void
+child_open (arg, from_tty)
+     char *arg;
+     int from_tty;
+{
+  error ("Use the \"run\" command to start a Unix child process.");
+}
+
+/* Start an inferior win32 child process and sets inferior_pid to its pid.
+   EXEC_FILE is the file to run.
+   ALLARGS is a string containing the arguments to the program.
+   ENV is the environment vector to pass.  Errors reported with error().  */
+
+static void
+child_create_inferior (exec_file, allargs, env)
+     char *exec_file;
+     char *allargs;
+     char **env;
+{
+  char real_path[MAXPATHLEN];
+  char *winenv;
+  char *temp;
+  int  envlen;
+  int i;
+
+  STARTUPINFO si;
+  PROCESS_INFORMATION pi;
+  struct target_waitstatus dummy;
+  BOOL ret;
+  DWORD flags;
+  char *args;
+
+  if (!exec_file)
+    {
+      error ("No executable specified, use `target exec'.\n");
+    }
+
+  memset (&si, 0, sizeof (si));
+  si.cb = sizeof (si);
+
+  cygwin32_conv_to_win32_path (exec_file, real_path);
+
+  flags = DEBUG_ONLY_THIS_PROCESS;
+
+  if (new_group)
+    flags |= CREATE_NEW_PROCESS_GROUP;
+
+  if (new_console)
+    flags |= CREATE_NEW_CONSOLE;
+
+  args = alloca (strlen (real_path) + strlen (allargs) + 2);
+
+  strcpy (args, real_path);
+
+  strcat (args, " ");
+  strcat (args, allargs);
+
+  /* Prepare the environment vars for CreateProcess.  */
+  {
+    /* This code use to assume all env vars were file names and would
+       translate them all to win32 style.  That obviously doesn't work in the
+       general case.  The current rule is that we only translate PATH.
+       We need to handle PATH because we're about to call CreateProcess and
+       it uses PATH to find DLL's.  Fortunately PATH has a well-defined value
+       in both posix and win32 environments.  cygwin.dll will change it back
+       to posix style if necessary.  */
+
+    static const char *conv_path_names[] =
+      {
+	"PATH=",
+	0
+      };
+
+    /* CreateProcess takes the environment list as a null terminated set of
+       strings (i.e. two nulls terminate the list).  */
+
+    /* Get total size for env strings.  */
+    for (envlen = 0, i = 0; env[i] && *env[i]; i++)
+      {
+	int j, len;
+
+	for (j = 0; conv_path_names[j]; j++)
+	  {
+	    len = strlen (conv_path_names[j]);
+	    if (strncmp (conv_path_names[j], env[i], len) == 0)
+	      {
+		if (cygwin32_posix_path_list_p (env[i] + len))
+		  envlen += len
+		    + cygwin32_posix_to_win32_path_list_buf_size (env[i] + len);
+		else
+		  envlen += strlen (env[i]) + 1;
+		break;
+	      }
+	  }
+	if (conv_path_names[j] == NULL)
+	  envlen += strlen (env[i]) + 1;
+      }
+
+    winenv = alloca (envlen + 1);
+
+    /* Copy env strings into new buffer.  */
+    for (temp = winenv, i = 0; env[i] && *env[i]; i++)
+      {
+	int j, len;
+
+	for (j = 0; conv_path_names[j]; j++)
+	  {
+	    len = strlen (conv_path_names[j]);
+	    if (strncmp (conv_path_names[j], env[i], len) == 0)
+	      {
+		if (cygwin32_posix_path_list_p (env[i] + len))
+		  {
+		    memcpy (temp, env[i], len);
+		    cygwin32_posix_to_win32_path_list (env[i] + len, temp + len);
+		  }
+		else
+		  strcpy (temp, env[i]);
+		break;
+	      }
+	  }
+	if (conv_path_names[j] == NULL)
+	  strcpy (temp, env[i]);
+
+	temp += strlen (temp) + 1;
+      }
+
+    /* Final nil string to terminate new env.  */
+    *temp = 0;
+  }
+
+  ret = CreateProcess (0,
+		       args, 	/* command line */
+		       NULL,	/* Security */
+		       NULL,	/* thread */
+		       TRUE,	/* inherit handles */
+		       flags,	/* start flags */
+		       winenv,
+		       NULL,	/* current directory */
+		       &si,
+		       &pi);
+  if (!ret)
+    error ("Error creating process %s, (error %d)\n", exec_file, GetLastError());
+
+  exception_count = 0;
+  event_count = 0;
+
+  current_process_handle = pi.hProcess;
+  current_event.dwProcessId = pi.dwProcessId;
+  memset (&current_event, 0, sizeof (current_event));
+  inferior_pid = current_event.dwThreadId = pi.dwThreadId;
+  push_target (&child_ops);
+  child_init_thread_list ();
+  init_wait_for_inferior ();
+  clear_proceed_status ();
+  target_terminal_init ();
+  target_terminal_inferior ();
+
+  /* Ignore the first trap */
+  child_wait (inferior_pid, &dummy);
+
+  proceed ((CORE_ADDR) - 1, TARGET_SIGNAL_0, 0);
+}
+
+static void
+child_mourn_inferior ()
+{
+  (void) child_continue (DBG_CONTINUE, -1);
+  unpush_target (&child_ops);
+  generic_mourn_inferior ();
+}
+
+/* Send a SIGINT to the process group.  This acts just like the user typed a
+   ^C on the controlling terminal. */
+
+static void
+child_stop ()
+{
+  DEBUG_EVENTS (("gdb: GenerateConsoleCtrlEvent (CTRLC_EVENT, 0)\n"));
+  CHECK (GenerateConsoleCtrlEvent (CTRL_C_EVENT, 0));
+  registers_changed();		/* refresh register state */
+}
+
+int
+child_xfer_memory (CORE_ADDR memaddr, char *our, int len,
+		   int write, struct target_ops *target)
+{
+  DWORD done;
+  if (write)
+    {
+      DEBUG_MEM (("gdb: write target memory, %d bytes at 0x%08x\n",
+		  len, memaddr));
+      WriteProcessMemory (current_process_handle, (LPVOID) memaddr, our,
+			  len, &done);
+      FlushInstructionCache (current_process_handle, (LPCVOID) memaddr, len);
+    }
+  else
+    {
+      DEBUG_MEM (("gdb: read target memory, %d bytes at 0x%08x\n",
+		  len, memaddr));
+      ReadProcessMemory (current_process_handle, (LPCVOID) memaddr, our, len,
+			 &done);
+    }
+  return done;
+}
+
+void
+child_kill_inferior (void)
+{
+  CHECK (TerminateProcess (current_process_handle, 0));
+
+  for (;;)
+    {
+      if (!child_continue (DBG_CONTINUE, -1))
+	break;
+      if (!WaitForDebugEvent (&current_event, INFINITE))
+	break;
+      if (current_event.dwDebugEventCode == EXIT_PROCESS_DEBUG_EVENT)
+	break;
+    }
+
+  CHECK (CloseHandle (current_process_handle));
+
+  /* this may fail in an attached process so don't check. */
+  (void) CloseHandle (current_thread->h);
+  target_mourn_inferior();	/* or just child_mourn_inferior? */
+}
+
+void
+child_resume (int pid, int step, enum target_signal sig)
+{
+  int i;
+  thread_info *th;
+  DWORD continue_status = last_sig > 0 && last_sig < NSIG ?
+			  DBG_EXCEPTION_NOT_HANDLED : DBG_CONTINUE;
+
+  DEBUG_EXEC (("gdb: child_resume (pid=%d, step=%d, sig=%d);\n",
+	       pid, step, sig));
+
+  /* Get context for currently selected thread */
+  th = thread_rec (current_event.dwThreadId, FALSE);
+  if (step)
+    {
+#ifdef i386
+      /* Single step by setting t bit */
+      child_fetch_inferior_registers (PS_REGNUM);
+      th->context.EFlags |= FLAG_TRACE_BIT;
+#endif
+    }
+
+  if (th->context.ContextFlags)
+    {
+      CHECK (SetThreadContext (th->h, &th->context));
+      th->context.ContextFlags = 0;
+    }
+
+  /* Allow continuing with the same signal that interrupted us.
+     Otherwise complain. */
+  if (sig && sig != last_sig)
+    fprintf_unfiltered (gdb_stderr, "Can't send signals to the child.  signal %d\n", sig);
+
+  last_sig = 0;
+  child_continue (continue_status, pid);
+}
+
+static void
+child_prepare_to_store ()
+{
+  /* Do nothing, since we can store individual regs */
+}
+
+static int
+child_can_run ()
+{
+  return 1;
+}
+
+static void
+child_close ()
+{
+  DEBUG_EVENTS (("gdb: child_close, inferior_pid=%d\n", inferior_pid));
+}
+
+struct target_ops child_ops ;
+
+static void 
+init_child_ops(void)
+{
+  child_ops.to_shortname =   "child";
+  child_ops.to_longname =   "Win32 child process";
+  child_ops.to_doc =   "Win32 child process (started by the \"run\" command).";
+  child_ops.to_open =   child_open;
+  child_ops.to_close =   child_close;
+  child_ops.to_attach =   child_attach;
+  child_ops.to_detach =   child_detach;
+  child_ops.to_resume =   child_resume;
+  child_ops.to_wait  =   child_wait;
+  child_ops.to_fetch_registers  =   child_fetch_inferior_registers;
+  child_ops.to_store_registers  =   child_store_inferior_registers;
+  child_ops.to_prepare_to_store =   child_prepare_to_store;
+  child_ops.to_xfer_memory  =   child_xfer_memory;
+  child_ops.to_files_info  =   child_files_info;
+  child_ops.to_insert_breakpoint =   memory_insert_breakpoint;
+  child_ops.to_remove_breakpoint =   memory_remove_breakpoint;
+  child_ops.to_terminal_init  =   terminal_init_inferior;
+  child_ops.to_terminal_inferior =   terminal_inferior;
+  child_ops.to_terminal_ours_for_output =   terminal_ours_for_output;
+  child_ops.to_terminal_ours  =   terminal_ours;
+  child_ops.to_terminal_info  =   child_terminal_info;
+  child_ops.to_kill  =   child_kill_inferior;
+  child_ops.to_load  =   0;
+  child_ops.to_lookup_symbol =   0;
+  child_ops.to_create_inferior =   child_create_inferior;
+  child_ops.to_mourn_inferior =   child_mourn_inferior;
+  child_ops.to_can_run  =   child_can_run;
+  child_ops.to_notice_signals =   0;
+  child_ops.to_thread_alive  =   win32_child_thread_alive;
+  child_ops.to_stop  =   child_stop;
+  child_ops.to_stratum =   process_stratum;
+  child_ops.DONT_USE =   0;
+  child_ops.to_has_all_memory =   1;
+  child_ops.to_has_memory =   1;
+  child_ops.to_has_stack =   1;
+  child_ops.to_has_registers =   1;
+  child_ops.to_has_execution =   1;
+  child_ops.to_sections =   0;
+  child_ops.to_sections_end =   0;
+  child_ops.to_magic =   OPS_MAGIC;
+}
+
+void
+_initialize_inftarg ()
+{
+  struct cmd_list_element *c;
+  init_child_ops() ;
+
+  add_show_from_set
+    (add_set_cmd ("new-console", class_support, var_boolean,
+		  (char *) &new_console,
+		  "Set creation of new console when creating child process.",
+		  &setlist),
+     &showlist);
+
+  add_show_from_set
+    (add_set_cmd ("new-group", class_support, var_boolean,
+		  (char *) &new_group,
+		  "Set creation of new group when creating child process.",
+		  &setlist),
+     &showlist);
+
+  add_show_from_set
+    (add_set_cmd ("debugexec", class_support, var_boolean,
+		  (char *) &debug_exec,
+		  "Set whether to display execution in child process.",
+		  &setlist),
+     &showlist);
+
+  add_show_from_set
+    (add_set_cmd ("debugevents", class_support, var_boolean,
+		  (char *) &debug_events,
+		  "Set whether to display kernel events in child process.",
+		  &setlist),
+     &showlist);
+
+  add_show_from_set
+    (add_set_cmd ("debugmemory", class_support, var_boolean,
+		  (char *) &debug_memory,
+		  "Set whether to display memory accesses in child process.",
+		  &setlist),
+     &showlist);
+
+  add_show_from_set
+    (add_set_cmd ("debugexceptions", class_support, var_boolean,
+		  (char *) &debug_exceptions,
+		  "Set whether to display kernel exceptions in child process.",
+		  &setlist),
+     &showlist);
+
+  add_target (&child_ops);
+}
+
+/* Determine if the thread referenced by "pid" is alive
+   by "polling" it.  If WaitForSingleObject returns WAIT_OBJECT_0
+   it means that the pid has died.  Otherwise it is assumed to be alive. */
+static int
+win32_child_thread_alive (int pid)
+{
+  return WaitForSingleObject(thread_rec (pid, FALSE)->h, 0) == WAIT_OBJECT_0 ?
+	 FALSE : TRUE;
+}
+
+/* Convert pid to printable format. */
+char *
+cygwin_pid_to_str (int pid)
+{
+  static char buf[80];
+  if (pid == current_event.dwProcessId)
+    sprintf (buf, "process %d", pid);
+  else
+    sprintf (buf, "thread %d.0x%x", current_event.dwProcessId, pid);
+  return buf;
+}