/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/* dbus-file-win.c windows related file implementation (internal to D-Bus implementation)
*
* Copyright (C) 2002, 2003, 2006 Red Hat, Inc.
* Copyright (C) 2003 CodeFactory AB
*
* Licensed under the Academic Free License version 2.1
*
* 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 even the 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <config.h>
#include "dbus-protocol.h"
#include "dbus-string.h"
#include "dbus-internals.h"
#include "dbus-sysdeps-win.h"
#include "dbus-pipe.h"
#include <windows.h>
/**
* Thin wrapper around the read() system call that appends
* the data it reads to the DBusString buffer. It appends
* up to the given count.
*
* @param hnd the HANDLE to read from
* @param buffer the buffer to append data to
* @param count the amount of data to read
* @param error place to set an error
* @returns the number of bytes read or -1
*/
static int
_dbus_file_read (HANDLE hnd,
DBusString *buffer,
int count,
DBusError *error)
{
BOOL result;
DWORD bytes_read;
int start;
char *data;
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
_dbus_assert (count >= 0);
start = _dbus_string_get_length (buffer);
if (!_dbus_string_lengthen (buffer, count))
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
return -1;
}
data = _dbus_string_get_data_len (buffer, start, count);
result = ReadFile (hnd, data, count, &bytes_read, NULL);
if (result == 0)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Failed to read from 0x%x: %s", hnd, emsg);
_dbus_win_free_error_string (emsg);
return -1;
}
if (bytes_read)
{
/* put length back (doesn't actually realloc) */
_dbus_string_set_length (buffer, start + bytes_read);
#if 0
if (bytes_read > 0)
_dbus_verbose_bytes_of_string (buffer, start, bytes_read);
#endif
}
return bytes_read;
}
/**
* Appends the contents of the given file to the string,
* returning error code. At the moment, won't open a file
* more than a megabyte in size.
*
* @param str the string to append to
* @param filename filename to load
* @param error place to set an error
* @returns #FALSE if error was set
*/
dbus_bool_t
_dbus_file_get_contents (DBusString *str,
const DBusString *filename,
DBusError *error)
{
HANDLE hnd;
DWORD fsize;
DWORD fsize_hi;
int orig_len;
unsigned int total;
const char *filename_c;
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
filename_c = _dbus_string_get_const_data (filename);
hnd = CreateFileA (filename_c, GENERIC_READ,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (hnd == INVALID_HANDLE_VALUE)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Failed to open \"%s\": %s", filename_c, emsg);
_dbus_win_free_error_string (emsg);
return FALSE;
}
_dbus_verbose ("file %s hnd %p opened\n", filename_c, hnd);
fsize = GetFileSize (hnd, &fsize_hi);
if (fsize == 0xFFFFFFFF && GetLastError() != NO_ERROR)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Failed to get file size for \"%s\": %s",
filename_c, emsg);
_dbus_win_free_error_string (emsg);
_dbus_verbose ("GetFileSize() failed: %s", emsg);
CloseHandle (hnd);
return FALSE;
}
if (fsize_hi != 0 || fsize > _DBUS_ONE_MEGABYTE)
{
dbus_set_error (error, DBUS_ERROR_FAILED,
"File size %lu/%lu of \"%s\" is too large.",
(unsigned long) fsize_hi,
(unsigned long) fsize, filename_c);
CloseHandle (hnd);
return FALSE;
}
total = 0;
orig_len = _dbus_string_get_length (str);
if (fsize > 0)
{
int bytes_read;
while (total < fsize)
{
bytes_read = _dbus_file_read (hnd, str, fsize - total, error);
if (bytes_read <= 0)
{
if (bytes_read == 0)
{
dbus_set_error (error, DBUS_ERROR_FAILED,
"Premature EOF reading \"%s\"",
filename_c);
}
else
_DBUS_ASSERT_ERROR_IS_SET (error);
CloseHandle (hnd);
_dbus_string_set_length (str, orig_len);
return FALSE;
}
else
total += bytes_read;
}
CloseHandle (hnd);
return TRUE;
}
else
{
CloseHandle (hnd);
return TRUE;
}
}
/**
* Writes a string out to a file. If the file exists,
* it will be atomically overwritten by the new data.
*
* @param str the string to write out
* @param filename the file to save string to
* @param world_readable if true, ensure file is world readable
* @param error error to be filled in on failure
* @returns #FALSE on failure
*/
dbus_bool_t
_dbus_string_save_to_file (const DBusString *str,
const DBusString *filename,
dbus_bool_t world_readable,
DBusError *error)
{
HANDLE hnd;
int bytes_to_write;
const char *filename_c;
DBusString tmp_filename;
const char *tmp_filename_c;
int total;
const char *str_c;
dbus_bool_t need_unlink;
dbus_bool_t retval;
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
hnd = INVALID_HANDLE_VALUE;
retval = FALSE;
need_unlink = FALSE;
if (!_dbus_string_init (&tmp_filename))
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
return FALSE;
}
if (!_dbus_string_copy (filename, 0, &tmp_filename, 0))
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
_dbus_string_free (&tmp_filename);
return FALSE;
}
if (!_dbus_string_append (&tmp_filename, "."))
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
_dbus_string_free (&tmp_filename);
return FALSE;
}
#define N_TMP_FILENAME_RANDOM_BYTES 8
if (!_dbus_generate_random_ascii (&tmp_filename, N_TMP_FILENAME_RANDOM_BYTES))
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
_dbus_string_free (&tmp_filename);
return FALSE;
}
filename_c = _dbus_string_get_const_data (filename);
tmp_filename_c = _dbus_string_get_const_data (&tmp_filename);
/* TODO - support world-readable in an atomic fashion */
hnd = CreateFileA (tmp_filename_c, GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL,
INVALID_HANDLE_VALUE);
if (hnd == INVALID_HANDLE_VALUE)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Could not create \"%s\": %s", filename_c, emsg);
_dbus_win_free_error_string (emsg);
goto out;
}
if (world_readable)
{
if (! _dbus_make_file_world_readable (&tmp_filename, error))
goto out;
}
_dbus_verbose ("tmp file %s hnd %p opened\n", tmp_filename_c, hnd);
need_unlink = TRUE;
total = 0;
bytes_to_write = _dbus_string_get_length (str);
str_c = _dbus_string_get_const_data (str);
while (total < bytes_to_write)
{
DWORD bytes_written;
BOOL res;
res = WriteFile (hnd, str_c + total, bytes_to_write - total,
&bytes_written, NULL);
if (res == 0 || bytes_written <= 0)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Could not write to %s: %s", tmp_filename_c, emsg);
_dbus_win_free_error_string (emsg);
goto out;
}
total += bytes_written;
}
if (CloseHandle (hnd) == 0)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Could not close file %s: %s", tmp_filename_c, emsg);
_dbus_win_free_error_string (emsg);
goto out;
}
hnd = INVALID_HANDLE_VALUE;
/* Unlike rename(), MoveFileEx() can replace existing files */
if (!MoveFileExA (tmp_filename_c, filename_c, MOVEFILE_REPLACE_EXISTING))
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Could not rename %s to %s: %s",
tmp_filename_c, filename_c, emsg);
_dbus_win_free_error_string (emsg);
goto out;
}
need_unlink = FALSE;
retval = TRUE;
out:
/* close first, then unlink */
if (hnd != INVALID_HANDLE_VALUE)
CloseHandle (hnd);
if (need_unlink && DeleteFileA (tmp_filename_c) == 0)
{
char *emsg = _dbus_win_error_string (GetLastError ());
_dbus_verbose ("Failed to unlink temp file %s: %s", tmp_filename_c,
emsg);
_dbus_win_free_error_string (emsg);
}
_dbus_string_free (&tmp_filename);
if (!retval)
_DBUS_ASSERT_ERROR_IS_SET (error);
return retval;
}
/** Creates the given file, failing if the file already exists.
*
* @param filename the filename
* @param error error location
* @returns #TRUE if we created the file and it didn't exist
*/
dbus_bool_t
_dbus_create_file_exclusively (const DBusString *filename,
DBusError *error)
{
HANDLE hnd;
const char *filename_c;
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
filename_c = _dbus_string_get_const_data (filename);
hnd = CreateFileA (filename_c, GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL,
INVALID_HANDLE_VALUE);
if (hnd == INVALID_HANDLE_VALUE)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Could not create file %s: %s",
filename_c, emsg);
_dbus_win_free_error_string (emsg);
return FALSE;
}
_dbus_verbose ("exclusive file %s hnd %p opened\n", filename_c, hnd);
if (CloseHandle (hnd) == 0)
{
char *emsg = _dbus_win_error_string (GetLastError ());
dbus_set_error (error, _dbus_win_error_from_last_error (),
"Could not close file %s: %s",
filename_c, emsg);
_dbus_win_free_error_string (emsg);
return FALSE;
}
return TRUE;
}