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-rw-r--r--src/liblzma/common/stream_buffer_encoder.c138
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diff --git a/src/liblzma/common/stream_buffer_encoder.c b/src/liblzma/common/stream_buffer_encoder.c
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+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file stream_buffer_encoder.c
+/// \brief Single-call .xz Stream encoder
+//
+// Copyright (C) 2009 Lasse Collin
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Lesser General Public License for more details.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "index.h"
+
+
+/// Maximum size of Index that has exactly one Record.
+/// Index Indicator + Number of Records + Record + CRC32 rounded up to
+/// the next multiple of four.
+#define INDEX_BOUND ((1 + 1 + 2 * LZMA_VLI_BYTES_MAX + 4 + 3) & ~3)
+
+/// Stream Header, Stream Footer, and Index
+#define HEADERS_BOUND (2 * LZMA_STREAM_HEADER_SIZE + INDEX_BOUND)
+
+
+extern LZMA_API size_t
+lzma_stream_buffer_bound(size_t uncompressed_size)
+{
+ // Get the maximum possible size of a Block.
+ const size_t block_bound = lzma_block_buffer_bound(uncompressed_size);
+ if (block_bound == 0)
+ return 0;
+
+ // Catch the possible integer overflow and also prevent the size of
+ // the Stream exceeding LZMA_VLI_MAX (theoretically possible on
+ // 64-bit systems).
+ if (MIN(SIZE_MAX, LZMA_VLI_MAX) - block_bound < HEADERS_BOUND)
+ return 0;
+
+ return block_bound + HEADERS_BOUND;
+}
+
+
+extern LZMA_API lzma_ret
+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;
+
+ // 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
+ // Stream Footer.
+ if (out_size - out_pos <= 2 * LZMA_STREAM_HEADER_SIZE)
+ return LZMA_BUF_ERROR;
+
+ // Reserve space for Stream Footer so we don't need to check for
+ // available space again before encoding Stream Footer.
+ out_size -= LZMA_STREAM_HEADER_SIZE;
+
+ // Encode the Stream Header.
+ lzma_stream_flags stream_flags = {
+ .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
+ 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));
+
+ // Index
+ {
+ // Create an Index with one Record.
+ lzma_index *i = lzma_index_init(NULL, NULL);
+ if (i == NULL)
+ return LZMA_MEM_ERROR;
+
+ lzma_ret ret = lzma_index_append(i, NULL,
+ 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, NULL);
+
+ 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;
+}