/* registry.cc: registry interface

   Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   2005, 2006, 2007, 2008, 2009, 2010, 2011 Red Hat, Inc.

This file is part of Cygwin.

This software is a copyrighted work licensed under the terms of the
Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
details. */

#include "winsup.h"
#include "registry.h"
#include "cygerrno.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#include "tls_pbuf.h"
#include "ntdll.h"
#include <wchar.h>
#include <alloca.h>

/* Opens a key under the appropriate Cygwin key.
   Do not use HKCU per MS KB 199190  */
static NTSTATUS
top_key (bool isHKLM, REGSAM access, PHANDLE top)
{
  WCHAR rbuf[PATH_MAX], *p;
  UNICODE_STRING rpath;
  OBJECT_ATTRIBUTES attr;
  NTSTATUS status;

  InitializeObjectAttributes (&attr, &rpath, OBJ_CASE_INSENSITIVE, NULL, NULL);
  if (isHKLM)
    {
      wcpcpy (rbuf, L"\\Registry\\Machine");
      RtlInitUnicodeString (&rpath, rbuf);
      status = NtOpenKey (top, access, &attr);
    }
  else
    {
      WCHAR name[128];
      PCWSTR names[2] = {cygheap->user.get_windows_id (name),
			 L".DEFAULT"};

      p = wcpcpy (rbuf, L"\\Registry\\User\\");
      for (int i = 0; i < 2; i++)
	{
	  wcpcpy (p, names[i]);
	  RtlInitUnicodeString (&rpath, rbuf);
	  status = NtOpenKey (top, access, &attr);
	  if (NT_SUCCESS (status))
	    break;
	}
    }
  return status;
}

reg_key::reg_key (HKEY top, REGSAM access, ...): _disposition (0)
{
  va_list av;
  va_start (av, access);
  build_reg (top, access, av);
  va_end (av);
}

reg_key::reg_key (bool isHKLM, REGSAM access, ...): _disposition (0)
{
  va_list av;
  HANDLE top;

  key_is_invalid = top_key (isHKLM, access, &top);
  if (NT_SUCCESS (key_is_invalid))
    {
      new (this) reg_key ((HKEY) top, access, L"SOFTWARE",
			  _WIDE (CYGWIN_INFO_CYGWIN_REGISTRY_NAME), NULL);
      NtClose (top);
      if (key_is_invalid)
	return;
      top = key;
      va_start (av, access);
      build_reg ((HKEY) top, access, av);
      va_end (av);
      if (top != key)
	NtClose (top);
    }
}

void
reg_key::build_reg (HKEY top, REGSAM access, va_list av)
{
  PWCHAR name;
  HANDLE r;
  UNICODE_STRING uname;
  OBJECT_ATTRIBUTES attr;
  NTSTATUS status;

  if (top != HKEY_LOCAL_MACHINE && top != HKEY_CURRENT_USER)
    r = (HANDLE) top;
  else if (!NT_SUCCESS (top_key (top == HKEY_LOCAL_MACHINE, access, &r)))
    return;
  key_is_invalid = 0;
  while ((name = va_arg (av, PWCHAR)) != NULL)
    {
      RtlInitUnicodeString (&uname, name);
      InitializeObjectAttributes (&attr, &uname,
				  OBJ_CASE_INSENSITIVE | OBJ_OPENIF, r, NULL);

      status = NtCreateKey (&key, access, &attr, 0, NULL,
			    REG_OPTION_NON_VOLATILE, &_disposition);
      if (r != (HANDLE) top)
	NtClose (r);
      r = key;
      if (!NT_SUCCESS (status))
	{
	  key_is_invalid = status;
	  debug_printf ("failed to create key %S in the registry", uname);
	  break;
	}
    }
}

/* Given the current registry key, return the specific int value
   requested.  Return def on failure. */

int
reg_key::get_int (PCWSTR name, int def)
{
  if (key_is_invalid)
    return def;

  NTSTATUS status;
  UNICODE_STRING uname;
  ULONG size = sizeof (KEY_VALUE_PARTIAL_INFORMATION) + sizeof (DWORD);
  ULONG rsize;
  PKEY_VALUE_PARTIAL_INFORMATION vbuf = (PKEY_VALUE_PARTIAL_INFORMATION)
				      alloca (size);

  RtlInitUnicodeString (&uname, name);
  status = NtQueryValueKey (key, &uname, KeyValuePartialInformation, vbuf,
			    size, &rsize);
  if (status != STATUS_SUCCESS || vbuf->Type != REG_DWORD)
    return def;
  DWORD dst = *(DWORD *) vbuf->Data;
  return (int) dst;
}

/* Given the current registry key, set a specific int value. */

int
reg_key::set_int (PCWSTR name, int val)
{
  if (key_is_invalid)
    return key_is_invalid;

  DWORD value = (DWORD) val;
  UNICODE_STRING uname;
  RtlInitUnicodeString (&uname, name);
  NTSTATUS status = NtSetValueKey (key, &uname, 0, REG_DWORD, 
				   &value, sizeof (value));
  return (int) status;
}

/* Given the current registry key, return the specific string value
   requested.  Return zero on success, non-zero on failure. */

int
reg_key::get_string (PCWSTR name, PWCHAR dst, size_t max, PCWSTR def)
{
  NTSTATUS status;

  if (key_is_invalid)
    {
      status = key_is_invalid;
      if (def != NULL)
	wcpncpy (dst, def, max);
    }
  else
    {
      UNICODE_STRING uname;
      ULONG size = sizeof (KEY_VALUE_PARTIAL_INFORMATION) + max * sizeof (WCHAR);
      ULONG rsize;
      PKEY_VALUE_PARTIAL_INFORMATION vbuf = (PKEY_VALUE_PARTIAL_INFORMATION)
					  alloca (size);

      RtlInitUnicodeString (&uname, name);
      status = NtQueryValueKey (key, &uname, KeyValuePartialInformation, vbuf,
				size, &rsize);
      if (status != STATUS_SUCCESS || vbuf->Type != REG_SZ)
	wcpncpy (dst, def, max);
      else
	wcpncpy (dst, (PWCHAR) vbuf->Data, max);
      
    }
  return (int) status;
}

/* Given the current registry key, set a specific string value. */

int
reg_key::set_string (PCWSTR name, PCWSTR src)
{
  if (key_is_invalid)
    return key_is_invalid;

  UNICODE_STRING uname;
  RtlInitUnicodeString (&uname, name);
  NTSTATUS status = NtSetValueKey (key, &uname, 0, REG_SZ, (PVOID) src,
				   (wcslen (src) + 1) * sizeof (WCHAR));
  return (int) status;
}

reg_key::~reg_key ()
{
  if (!key_is_invalid)
    NtClose (key);
  key_is_invalid = 1;
}

PWCHAR
get_registry_hive_path (PCWSTR name, PWCHAR path)
{
  if (!name || !path)
    return NULL;

  WCHAR key[256];
  UNICODE_STRING buf;
  tmp_pathbuf tp;
  tp.u_get (&buf);
  NTSTATUS status;

  RTL_QUERY_REGISTRY_TABLE tab[2] = {
    { NULL, RTL_QUERY_REGISTRY_NOEXPAND | RTL_QUERY_REGISTRY_DIRECT
	    | RTL_QUERY_REGISTRY_REQUIRED,
      L"ProfileImagePath", &buf, REG_NONE, NULL, 0 },
    { NULL, 0, NULL, NULL, 0, NULL, 0 }
  };
  wcpcpy (wcpcpy (key, L"ProfileList\\"), name);
  status = RtlQueryRegistryValues (RTL_REGISTRY_WINDOWS_NT, key, tab,
				   NULL, NULL);
  if (!NT_SUCCESS (status) || buf.Length == 0)
    {
      system_printf ("ProfileImagePath for %W not found, status %p", name,
		    status);
      return NULL;
    }
  wcpcpy (path, L"\\??\\");
  ExpandEnvironmentStringsW (buf.Buffer, path + 4, NT_MAX_PATH - 4);
  system_printf ("ProfileImagePath for %W: %W", name, path);
  return path;
}

void
load_registry_hive (PCWSTR name)
{
  if (!name)
    return;

  /* Fetch the path. */
  tmp_pathbuf tp;
  PWCHAR path = tp.w_get ();
  if (!get_registry_hive_path (name, path))
    return;

  WCHAR key[256];
  UNICODE_STRING ukey, upath;
  OBJECT_ATTRIBUTES key_attr, path_attr;
  NTSTATUS status;

  /* Create the object attributes for key and path. */
  wcpcpy (wcpcpy (key, L"\\Registry\\User\\"), name);
  RtlInitUnicodeString (&ukey, key);
  InitializeObjectAttributes (&key_attr, &ukey, OBJ_CASE_INSENSITIVE,
			      NULL, NULL);
  wcscat (path, L"\\NTUSER.DAT");
  RtlInitUnicodeString (&upath, path);
  InitializeObjectAttributes (&path_attr, &upath, OBJ_CASE_INSENSITIVE,
			      NULL, NULL);
  /* Load file into key. */
  status = NtLoadKey (&key_attr, &path_attr);
  if (!NT_SUCCESS (status))
    system_printf ("Loading user registry hive %S into %S failed: %p",
		  &upath, &ukey, status);
  else
    system_printf ("Loading user registry hive %S into %S SUCCEEDED: %p",
		  &upath, &ukey, status);
}