+ size_t compressed_size;
+
+ wimlib_assert(uncompressed_size <= c->max_block_size);
+
+ compressed_size = c->ops->compress(uncompressed_data,
+ uncompressed_size,
+ compressed_data,
+ compressed_size_avail,
+ c->private);
+
+ /* (Optional) Verify that we really get the same thing back when
+ * decompressing. Should always be the case, unless there's a bug. */
+#ifdef ENABLE_VERIFY_COMPRESSION
+ if (compressed_size != 0) {
+ struct wimlib_decompressor *d;
+ int res;
+ u8 *buf;
+
+ buf = MALLOC(uncompressed_size);
+ if (!buf) {
+ WARNING("Unable to verify results of %s compression "
+ "(can't allocate buffer)",
+ wimlib_get_compression_type_string(c->ctype));
+ return 0;
+ }
+
+ res = wimlib_create_decompressor(c->ctype,
+ c->max_block_size, &d);
+ if (res) {
+ WARNING("Unable to verify results of %s compression "
+ "(can't create decompressor)",
+ wimlib_get_compression_type_string(c->ctype));
+ FREE(buf);
+ return 0;
+ }
+
+ res = wimlib_decompress(compressed_data, compressed_size,
+ buf, uncompressed_size, d);
+ wimlib_free_decompressor(d);
+ if (res) {
+ ERROR("Failed to decompress our %s-compressed data",
+ wimlib_get_compression_type_string(c->ctype));
+ FREE(buf);
+ abort();
+ }
+
+ res = memcmp(uncompressed_data, buf, uncompressed_size);
+ FREE(buf);
+
+ if (res) {
+ ERROR("Our %s-compressed data did not decompress "
+ "to original",
+ wimlib_get_compression_type_string(c->ctype));
+ abort();
+ }
+ }
+#endif /* ENABLE_VERIFY_COMPRESSION */
+
+ return compressed_size;