+static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
+ uint16_t reference_checksum, uint64_t valid_size)
+{
+ char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
+ /*
+ Validate checksum first. If it's invalid all other fields probably
+ contain just garbage.
+ */
+ if (actual_checksum != reference_checksum)
+ {
+ exfat_get_name(node, buffer, sizeof(buffer) - 1);
+ exfat_error("'%s' has invalid checksum (%#hx != %#hx)", buffer,
+ actual_checksum, reference_checksum);
+ return false;
+ }
+
+ /*
+ exFAT does not support sparse files but allows files with uninitialized
+ clusters. For such files valid_size means initialized data size and
+ cannot be greater than file size. See SetFileValidData() function
+ description in MSDN.
+ */
+ if (valid_size > node->size)
+ {
+ exfat_get_name(node, buffer, sizeof(buffer) - 1);
+ exfat_error("'%s' has valid size (%"PRIu64") greater than size "
+ "(%"PRIu64")", buffer, valid_size, node->size);
+ return false;
+ }
+
+ return true;
+}
+
+static void decompress_upcase(uint16_t* output, const le16_t* source,
+ size_t size)
+{
+ size_t si;
+ size_t oi;
+
+ for (oi = 0; oi < EXFAT_UPCASE_CHARS; oi++)
+ output[oi] = oi;
+
+ for (si = 0, oi = 0; si < size && oi < EXFAT_UPCASE_CHARS; si++)
+ {
+ uint16_t ch = le16_to_cpu(source[si]);
+
+ if (ch == 0xffff && si + 1 < size) /* indicates a run */
+ oi += le16_to_cpu(source[++si]);
+ else
+ output[oi++] = ch;
+ }
+}
+