/**
* g_file_descriptor_based_get_fd:
* @fd_based: a #GFileDescriptorBased.
*
* Gets the underlying file descriptor.
*
* Returns: The file descriptor
*
* Since: 2.24
**/
int
g_file_descriptor_based_get_fd (GFileDescriptorBased *fd_based)
{
GFileDescriptorBasedIface *iface;
g_return_val_if_fail (G_IS_FILE_DESCRIPTOR_BASED (fd_based), 0);
iface = G_FILE_DESCRIPTOR_BASED_GET_IFACE (fd_based);
return (* iface->get_fd) (fd_based);
}
gboolean
_ostree_static_delta_part_open (GInputStream *part_in,
GBytes *inline_part_bytes,
OstreeStaticDeltaOpenFlags flags,
const char *expected_checksum,
GVariant **out_part,
GCancellable *cancellable,
GError **error)
{
gboolean ret = FALSE;
const gboolean trusted = (flags & OSTREE_STATIC_DELTA_OPEN_FLAGS_VARIANT_TRUSTED) > 0;
const gboolean skip_checksum = (flags & OSTREE_STATIC_DELTA_OPEN_FLAGS_SKIP_CHECKSUM) > 0;
gsize bytes_read;
guint8 comptype;
g_autoptr(GChecksum) checksum = NULL;
g_autoptr(GInputStream) checksum_in = NULL;
g_autoptr(GVariant) ret_part = NULL;
GInputStream *source_in;
/* We either take a fd or a GBytes reference */
g_return_val_if_fail (G_IS_FILE_DESCRIPTOR_BASED (part_in) || inline_part_bytes != NULL, FALSE);
g_return_val_if_fail (skip_checksum || expected_checksum != NULL, FALSE);
if (!skip_checksum)
{
checksum = g_checksum_new (G_CHECKSUM_SHA256);
checksum_in = (GInputStream*)ostree_checksum_input_stream_new (part_in, checksum);
source_in = checksum_in;
}
else
{
source_in = part_in;
}
{ guint8 buf[1];
/* First byte is compression type */
if (!g_input_stream_read_all (source_in, buf, sizeof(buf), &bytes_read,
cancellable, error))
{
g_prefix_error (error, "Reading initial compression flag byte: ");
goto out;
}
comptype = buf[0];
}
switch (comptype)
{
case 0:
if (!inline_part_bytes)
{
int part_fd = g_file_descriptor_based_get_fd ((GFileDescriptorBased*)part_in);
/* No compression, no checksums - a fast path */
if (!ot_util_variant_map_fd (part_fd, 1, G_VARIANT_TYPE (OSTREE_STATIC_DELTA_PART_PAYLOAD_FORMAT_V0),
trusted, &ret_part, error))
goto out;
}
else
{
g_autoptr(GBytes) content_bytes = g_bytes_new_from_bytes (inline_part_bytes, 1,
g_bytes_get_size (inline_part_bytes) - 1);
ret_part = g_variant_new_from_bytes (G_VARIANT_TYPE (OSTREE_STATIC_DELTA_PART_PAYLOAD_FORMAT_V0),
content_bytes, trusted);
g_variant_ref_sink (ret_part);
}
if (!skip_checksum)
g_checksum_update (checksum, g_variant_get_data (ret_part),
g_variant_get_size (ret_part));
break;
case 'x':
{
g_autofree char *tmppath = g_strdup ("/var/tmp/ostree-delta-XXXXXX");
g_autoptr(GConverter) decomp = (GConverter*) _ostree_lzma_decompressor_new ();
g_autoptr(GInputStream) convin = g_converter_input_stream_new (source_in, decomp);
g_autoptr(GOutputStream) unpacked_out = NULL;
glnx_fd_close int unpacked_fd = -1;
gssize n_bytes_written;
unpacked_fd = g_mkstemp_full (tmppath, O_RDWR | O_CLOEXEC, 0640);
if (unpacked_fd < 0)
{
glnx_set_error_from_errno (error);
goto out;
}
/* Now make it autocleanup on process exit - in the future, we
* should consider caching unpacked deltas as well.
*/
if (unlink (tmppath) < 0)
{
glnx_set_error_from_errno (error);
goto out;
}
unpacked_out = g_unix_output_stream_new (unpacked_fd, FALSE);
n_bytes_written = g_output_stream_splice (unpacked_out, convin,
G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE |
G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET,
cancellable, error);
if (n_bytes_written < 0)
goto out;
if (!ot_util_variant_map_fd (unpacked_fd, 0, G_VARIANT_TYPE (OSTREE_STATIC_DELTA_PART_PAYLOAD_FORMAT_V0),
trusted, &ret_part, error))
goto out;
}
break;
default:
g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
"Invalid compression type '%u'", comptype);
goto out;
}
if (checksum)
{
const char *actual_checksum = g_checksum_get_string (checksum);
g_assert (expected_checksum != NULL);
if (strcmp (actual_checksum, expected_checksum) != 0)
{
g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
"Checksum mismatch in static delta part; expected=%s actual=%s",
expected_checksum, actual_checksum);
goto out;
}
}
ret = TRUE;
*out_part = g_steal_pointer (&ret_part);
out:
return ret;
}
gboolean
_ostree_static_delta_part_open (GInputStream *part_in,
GBytes *inline_part_bytes,
OstreeStaticDeltaOpenFlags flags,
const char *expected_checksum,
GVariant **out_part,
GCancellable *cancellable,
GError **error)
{
const gboolean trusted = (flags & OSTREE_STATIC_DELTA_OPEN_FLAGS_VARIANT_TRUSTED) > 0;
const gboolean skip_checksum = (flags & OSTREE_STATIC_DELTA_OPEN_FLAGS_SKIP_CHECKSUM) > 0;
gsize bytes_read;
guint8 comptype;
g_autoptr(GChecksum) checksum = NULL;
g_autoptr(GInputStream) checksum_in = NULL;
GInputStream *source_in;
/* We either take a fd or a GBytes reference */
g_return_val_if_fail (G_IS_FILE_DESCRIPTOR_BASED (part_in) || inline_part_bytes != NULL, FALSE);
g_return_val_if_fail (skip_checksum || expected_checksum != NULL, FALSE);
if (!skip_checksum)
{
checksum = g_checksum_new (G_CHECKSUM_SHA256);
checksum_in = (GInputStream*)ostree_checksum_input_stream_new (part_in, checksum);
source_in = checksum_in;
}
else
{
source_in = part_in;
}
{ guint8 buf[1];
/* First byte is compression type */
if (!g_input_stream_read_all (source_in, buf, sizeof(buf), &bytes_read,
cancellable, error))
return glnx_prefix_error (error, "Reading initial compression flag byte");
comptype = buf[0];
}
g_autoptr(GVariant) ret_part = NULL;
switch (comptype)
{
case 0:
if (!inline_part_bytes)
{
int part_fd = g_file_descriptor_based_get_fd ((GFileDescriptorBased*)part_in);
/* No compression, no checksums - a fast path */
if (!ot_util_variant_map_fd (part_fd, 1, G_VARIANT_TYPE (OSTREE_STATIC_DELTA_PART_PAYLOAD_FORMAT_V0),
trusted, &ret_part, error))
return FALSE;
}
else
{
g_autoptr(GBytes) content_bytes = g_bytes_new_from_bytes (inline_part_bytes, 1,
g_bytes_get_size (inline_part_bytes) - 1);
ret_part = g_variant_new_from_bytes (G_VARIANT_TYPE (OSTREE_STATIC_DELTA_PART_PAYLOAD_FORMAT_V0),
content_bytes, trusted);
g_variant_ref_sink (ret_part);
}
if (!skip_checksum)
g_checksum_update (checksum, g_variant_get_data (ret_part),
g_variant_get_size (ret_part));
break;
case 'x':
{
g_autoptr(GConverter) decomp = (GConverter*) _ostree_lzma_decompressor_new ();
g_autoptr(GInputStream) convin = g_converter_input_stream_new (source_in, decomp);
g_autoptr(GBytes) buf = ot_map_anonymous_tmpfile_from_content (convin, cancellable, error);
if (!buf)
return FALSE;
ret_part = g_variant_new_from_bytes (G_VARIANT_TYPE (OSTREE_STATIC_DELTA_PART_PAYLOAD_FORMAT_V0),
buf, FALSE);
}
break;
default:
return glnx_throw (error, "Invalid compression type '%u'", comptype);
}
if (checksum)
{
const char *actual_checksum = g_checksum_get_string (checksum);
g_assert (expected_checksum != NULL);
if (strcmp (actual_checksum, expected_checksum) != 0)
return glnx_throw (error, "Checksum mismatch in static delta part; expected=%s actual=%s",
expected_checksum, actual_checksum);
}
*out_part = g_steal_pointer (&ret_part);
return TRUE;
}
/**
* ot_file_replace_contents_at:
*
* Like g_file_replace_contents(), except using a fd-relative
* directory, and optionally enforces use of fdatasync().
*/
gboolean
ot_file_replace_contents_at (int dfd,
const char *path,
GBytes *contents,
gboolean datasync,
GCancellable *cancellable,
GError **error)
{
gboolean ret = FALSE;
int fd;
g_autofree char *tmpname = NULL;
g_autoptr(GOutputStream) stream = NULL;
g_autoptr(GInputStream) instream = NULL;
if (!gs_file_open_in_tmpdir_at (dfd, 0644,
&tmpname, &stream,
cancellable, error))
goto out;
g_assert (G_IS_FILE_DESCRIPTOR_BASED (stream));
fd = g_file_descriptor_based_get_fd (G_FILE_DESCRIPTOR_BASED (stream));
instream = g_memory_input_stream_new_from_bytes (contents);
if (g_bytes_get_size (contents) > 0)
{
int r = posix_fallocate (fd, 0, g_bytes_get_size (contents));
if (r != 0)
{
/* posix_fallocate is a weird deviation from errno standards */
errno = r;
glnx_set_error_from_errno (error);
goto out;
}
}
if (g_output_stream_splice (stream, instream, 0,
cancellable, error) < 0)
goto out;
if (datasync && fdatasync (fd) != 0)
{
glnx_set_error_from_errno (error);
goto out;
}
if (!g_output_stream_close (stream, cancellable, error))
goto out;
if (renameat (dfd, tmpname, dfd, path) == -1)
{
glnx_set_error_from_errno (error);
goto out;
}
g_clear_pointer (&tmpname, g_free);
ret = TRUE;
out:
if (tmpname)
(void) unlinkat (dfd, tmpname, 0);
return ret;
}
