if (!(reshdr.flags & (WIM_RESHDR_FLAG_PACKED_STREAMS |
WIM_RESHDR_FLAG_COMPRESSED))) {
if (reshdr.uncompressed_size != reshdr.size_in_wim) {
- ERROR("Invalid resource entry!");
- ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
- goto err;
+ /* So ... This is an uncompressed resource, but
+ * its uncompressed size is NOT the same as its
+ * "compressed" size (size_in_wim). What to do
+ * with it?
+ *
+ * Based on a simple test, WIMGAPI seems to
+ * handle this as follows:
+ *
+ * if (size_in_wim > uncompressed_size) {
+ * Ignore uncompressed_size; use
+ * size_in_wim instead.
+ * } else {
+ * Honor uncompressed_size, but treat the
+ * part of the file data above size_in_wim
+ * as all zeros.
+ * }
+ *
+ * So we will do the same.
+ */
+ if (reshdr.size_in_wim > reshdr.uncompressed_size)
+ reshdr.uncompressed_size = reshdr.size_in_wim;
}
}
goto out_free_memory;
}
+static int
+fill_zeroes(u64 size, consume_data_callback_t cb, void *cb_ctx)
+{
+ if (unlikely(size)) {
+ u8 buf[min(size, BUFFER_SIZE)];
+
+ memset(buf, 0, sizeof(buf));
+
+ do {
+ size_t len;
+ int ret;
+
+ len = min(size, BUFFER_SIZE);
+ ret = cb(buf, len, cb_ctx);
+ if (ret)
+ return ret;
+ size -= len;
+ } while (size);
+ }
+ return 0;
+}
+
/* Read raw data from a file descriptor at the specified offset, feeding the
* data it in chunks into the specified callback function. */
static int
return read_compressed_wim_resource(rspec, &range, 1,
cb, cb_ctx);
} else {
- return read_raw_file_data(&rspec->wim->in_fd,
- rspec->offset_in_wim + offset,
- size,
- cb,
- cb_ctx);
+ /* Reading uncompressed resource. For completeness, handle the
+ * weird case where size_in_wim < uncompressed_size. */
+
+ u64 read_size;
+ u64 zeroes_size;
+ int ret;
+
+ if (likely(offset + size <= rspec->size_in_wim) ||
+ rspec->is_pipable)
+ {
+ read_size = size;
+ zeroes_size = 0;
+ } else {
+ if (offset >= rspec->size_in_wim) {
+ read_size = 0;
+ zeroes_size = size;
+ } else {
+ read_size = rspec->size_in_wim - offset;
+ zeroes_size = offset + size - rspec->size_in_wim;
+ }
+ }
+
+ ret = read_raw_file_data(&rspec->wim->in_fd,
+ rspec->offset_in_wim + offset,
+ read_size,
+ cb,
+ cb_ctx);
+ if (ret)
+ return ret;
+
+ return fill_zeroes(zeroes_size, cb, cb_ctx);
}
}