/**
* change_label - change the current label on a device
* @dev: device to change the label on
* @mnt_flags: mount flags of the device or 0 if not mounted
* @mnt_point: mount point of the device or NULL
* @label: the new label
*
* Change the label on the device @dev to @label.
*/
static int change_label(ntfs_volume *vol, unsigned long mnt_flags, char *label, BOOL force)
{
ntfs_attr_search_ctx *ctx;
ntfschar *new_label = NULL;
ATTR_RECORD *a;
int label_len;
int result = 0;
//XXX significant?
if (mnt_flags & NTFS_MF_MOUNTED) {
/* If not the root fs or mounted read/write, refuse change. */
if (!(mnt_flags & NTFS_MF_ISROOT) ||
!(mnt_flags & NTFS_MF_READONLY)) {
if (!force) {
ntfs_log_error("Refusing to change label on "
"read-%s mounted device %s.\n",
mnt_flags & NTFS_MF_READONLY ?
"only" : "write", opts.device);
return 1;
}
}
}
ctx = ntfs_attr_get_search_ctx(vol->vol_ni, NULL);
if (!ctx) {
ntfs_log_perror("Failed to get attribute search context");
goto err_out;
}
if (ntfs_attr_lookup(AT_VOLUME_NAME, AT_UNNAMED, 0, 0, 0, NULL, 0,
ctx)) {
if (errno != ENOENT) {
ntfs_log_perror("Lookup of $VOLUME_NAME attribute failed");
goto err_out;
}
/* The volume name attribute does not exist. Need to add it. */
a = NULL;
} else {
a = ctx->attr;
if (a->non_resident) {
ntfs_log_error("Error: Attribute $VOLUME_NAME must be "
"resident.\n");
goto err_out;
}
}
label_len = ntfs_mbstoucs(label, &new_label, 0);
if (label_len == -1) {
ntfs_log_perror("Unable to convert label string to Unicode");
goto err_out;
}
label_len *= sizeof(ntfschar);
if (label_len > 0x100) {
ntfs_log_error("New label is too long. Maximum %u characters "
"allowed. Truncating excess characters.\n",
(unsigned)(0x100 / sizeof(ntfschar)));
label_len = 0x100;
new_label[label_len / sizeof(ntfschar)] = 0;
}
if (a) {
if (resize_resident_attribute_value(ctx->mrec, a, label_len)) {
ntfs_log_perror("Error resizing resident attribute");
goto err_out;
}
} else {
/* sizeof(resident attribute record header) == 24 */
int asize = (24 + label_len + 7) & ~7;
u32 biu = le32_to_cpu(ctx->mrec->bytes_in_use);
if (biu + asize > le32_to_cpu(ctx->mrec->bytes_allocated)) {
errno = ENOSPC;
ntfs_log_perror("Error adding resident attribute");
goto err_out;
}
a = ctx->attr;
memmove((u8*)a + asize, a, biu - ((u8*)a - (u8*)ctx->mrec));
ctx->mrec->bytes_in_use = cpu_to_le32(biu + asize);
a->type = AT_VOLUME_NAME;
a->length = cpu_to_le32(asize);
a->non_resident = 0;
a->name_length = 0;
a->name_offset = cpu_to_le16(24);
a->flags = cpu_to_le16(0);
a->instance = ctx->mrec->next_attr_instance;
ctx->mrec->next_attr_instance = cpu_to_le16((le16_to_cpu(
ctx->mrec->next_attr_instance) + 1) & 0xffff);
a->u.res.value_length = cpu_to_le32(label_len);
a->u.res.value_offset = a->name_offset;
a->u.res.resident_flags = 0;
a->u.res.reservedR = 0;
}
memcpy((u8*)a + le16_to_cpu(a->u.res.value_offset), new_label, label_len);
if (!opts.noaction && ntfs_inode_sync(vol->vol_ni)) {
ntfs_log_perror("Error writing MFT Record to disk");
goto err_out;
}
result = 0;
err_out:
free(new_label);
return result;
}
int ntfs_change_label(ntfs_volume *vol, char *label)
{
ntfs_attr_search_ctx *ctx;
ntfschar *new_label = NULL;
ATTR_RECORD *a;
int label_len;
int result = 0;
ctx = ntfs_attr_get_search_ctx(vol->vol_ni, NULL);
if (!ctx) {
ntfs_log_perror("Failed to get attribute search context");
goto err_out;
}
if (ntfs_attr_lookup(AT_VOLUME_NAME, AT_UNNAMED, 0, 0, 0, NULL, 0,
ctx)) {
if (errno != ENOENT) {
ntfs_log_perror("Lookup of $VOLUME_NAME attribute failed");
goto err_out;
}
/* The volume name attribute does not exist. Need to add it. */
a = NULL;
} else {
a = ctx->attr;
if (a->non_resident) {
ntfs_log_error("Error: Attribute $VOLUME_NAME must be "
"resident.\n");
goto err_out;
}
}
label_len = ntfs_mbstoucs(label, &new_label);
if (label_len == -1) {
ntfs_log_perror("Unable to convert label string to Unicode");
goto err_out;
}
label_len *= sizeof(ntfschar);
if (label_len > 0x100) {
ntfs_log_error("New label is too long. Maximum %u characters "
"allowed. Truncating excess characters.\n",
(unsigned)(0x100 / sizeof(ntfschar)));
label_len = 0x100;
new_label[label_len / sizeof(ntfschar)] = cpu_to_le16(L'\0');
}
if (a) {
if (resize_resident_attribute_value(ctx->mrec, a, label_len)) {
ntfs_log_perror("Error resizing resident attribute");
goto err_out;
}
} else {
/* sizeof(resident attribute record header) == 24 */
int asize = (24 + label_len + 7) & ~7;
u32 biu = le32_to_cpu(ctx->mrec->bytes_in_use);
if (biu + asize > le32_to_cpu(ctx->mrec->bytes_allocated)) {
errno = ENOSPC;
ntfs_log_perror("Error adding resident attribute");
goto err_out;
}
a = ctx->attr;
memmove((u8*)a + asize, a, biu - ((u8*)a - (u8*)ctx->mrec));
ctx->mrec->bytes_in_use = cpu_to_le32(biu + asize);
a->type = AT_VOLUME_NAME;
a->length = cpu_to_le32(asize);
a->non_resident = 0;
a->name_length = 0;
a->name_offset = cpu_to_le16(24);
a->flags = cpu_to_le16(0);
a->instance = ctx->mrec->next_attr_instance;
ctx->mrec->next_attr_instance = cpu_to_le16((le16_to_cpu(
ctx->mrec->next_attr_instance) + 1) & 0xffff);
a->value_length = cpu_to_le32(label_len);
a->value_offset = a->name_offset;
a->resident_flags = 0;
a->reservedR = 0;
}
memcpy((u8*)a + le16_to_cpu(a->value_offset), new_label, label_len);
if (ntfs_inode_sync(vol->vol_ni)) {
ntfs_log_perror("Error writing MFT Record to disk");
goto err_out;
}
result = 0;
err_out:
ntfs_attr_put_search_ctx(ctx);
free(new_label);
return result;
}
