Update XZ Utils to 5.0.3 (in deps)

src/liblzma/common/stream_buffer_encoder.c

 ///////////////////////////////////////////////////////////////////////////////
 //
 /// \file       stream_buffer_encoder.c
 /// \brief      Single-call .xz Stream encoder
 //
 //  Author:     Lasse Collin
 //
 //  This file has been put into the public domain.
 //  You can do whatever you want with this file.
 //
@@ skipping 33 matching lines @@
 lzma_stream_buffer_encode(lzma_filter *filters, lzma_check check,
                 lzma_allocator *allocator, const uint8_t *in, size_t in_size,
                 uint8_t *out, size_t *out_pos_ptr, size_t out_size)
 {
         // Sanity checks
         if (filters == NULL || (unsigned int)(check) > LZMA_CHECK_ID_MAX
                         || (in == NULL && in_size != 0) || out == NULL
                         || out_pos_ptr == NULL || *out_pos_ptr > out_size)
                 return LZMA_PROG_ERROR;
 
+        if (!lzma_check_is_supported(check))
+                return LZMA_UNSUPPORTED_CHECK;
+
         // Note for the paranoids: Index encoder prevents the Stream from
         // getting too big and still being accepted with LZMA_OK, and Block
         // encoder catches if the input is too big. So we don't need to
         // separately check if the buffers are too big.
 
         // Use a local copy. We update *out_pos_ptr only if everything
         // succeeds.
         size_t out_pos = *out_pos_ptr;
 
         // Check that there's enough space for both Stream Header and
@@ skipping 10 matching lines @@
                 .version = 0,
                 .check = check,
         };
 
         if (lzma_stream_header_encode(&stream_flags, out + out_pos)
                         != LZMA_OK)
                 return LZMA_PROG_ERROR;
 
         out_pos += LZMA_STREAM_HEADER_SIZE;
 
-        // Block
+        // Encode a Block but only if there is at least one byte of input.
         lzma_block block = {
                 .version = 0,
                 .check = check,
                 .filters = filters,
         };
 
-        return_if_error(lzma_block_buffer_encode(&block, allocator,
-                        in, in_size, out, &out_pos, out_size));
+        if (in_size > 0)
+                return_if_error(lzma_block_buffer_encode(&block, allocator,
+                                in, in_size, out, &out_pos, out_size));
 
         // Index
         {
-                // Create an Index with one Record.
+                // Create an Index. It will have one Record if there was
+                // at least one byte of input to encode. Otherwise the
+                // Index will be empty.
                 lzma_index *i = lzma_index_init(allocator);
                 if (i == NULL)
                         return LZMA_MEM_ERROR;
 
-                lzma_ret ret = lzma_index_append(i, allocator,
-                                lzma_block_unpadded_size(&block),
-                                block.uncompressed_size);
+                lzma_ret ret = LZMA_OK;
+
+                if (in_size > 0)
+                        ret = lzma_index_append(i, allocator,
+                                        lzma_block_unpadded_size(&block),
+                                        block.uncompressed_size);
 
                 // If adding the Record was successful, encode the Index
                 // and get its size which will be stored into Stream Footer.
                 if (ret == LZMA_OK) {
                         ret = lzma_index_buffer_encode(
                                         i, out, &out_pos, out_size);
 
                         stream_flags.backward_size = lzma_index_size(i);
                 }
 
                 lzma_index_end(i, allocator);
 
                 if (ret != LZMA_OK)
                         return ret;
         }
 
         // Stream Footer. We have already reserved space for this.
         if (lzma_stream_footer_encode(&stream_flags, out + out_pos)
                         != LZMA_OK)
                 return LZMA_PROG_ERROR;
 
         out_pos += LZMA_STREAM_HEADER_SIZE;
 
         // Everything went fine, make the new output position available
         // to the application.
         *out_pos_ptr = out_pos;
         return LZMA_OK;
 }