integrate lzma

[zpackage] / lzma / common / block_buffer_decoder.c

diff --git a/lzma/common/block_buffer_decoder.c b/lzma/common/block_buffer_decoder.c
new file mode 100644 (file)
index 0000000..b0ded90
--- /dev/null
+++ b/lzma/common/block_buffer_decoder.c
@@ -0,0 +1,80 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       block_buffer_decoder.c
+/// \brief      Single-call .xz Block decoder
+//
+//  Author:     Lasse Collin
+//
+//  This file has been put into the public domain.
+//  You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "block_decoder.h"
+
+
+extern LZMA_API(lzma_ret)
+lzma_block_buffer_decode(lzma_block *block, const lzma_allocator *allocator,
+               const uint8_t *in, size_t *in_pos, size_t in_size,
+               uint8_t *out, size_t *out_pos, size_t out_size)
+{
+       if (in_pos == NULL || (in == NULL && *in_pos != in_size)
+                       || *in_pos > in_size || out_pos == NULL
+                       || (out == NULL && *out_pos != out_size)
+                       || *out_pos > out_size)
+               return LZMA_PROG_ERROR;
+
+       // Initialize the Block decoder.
+       lzma_next_coder block_decoder = LZMA_NEXT_CODER_INIT;
+       lzma_ret ret = lzma_block_decoder_init(
+                       &block_decoder, allocator, block);
+
+       if (ret == LZMA_OK) {
+               // Save the positions so that we can restore them in case
+               // an error occurs.
+               const size_t in_start = *in_pos;
+               const size_t out_start = *out_pos;
+
+               // Do the actual decoding.
+               ret = block_decoder.code(block_decoder.coder, allocator,
+                               in, in_pos, in_size, out, out_pos, out_size,
+                               LZMA_FINISH);
+
+               if (ret == LZMA_STREAM_END) {
+                       ret = LZMA_OK;
+               } else {
+                       if (ret == LZMA_OK) {
+                               // Either the input was truncated or the
+                               // output buffer was too small.
+                               assert(*in_pos == in_size
+                                               || *out_pos == out_size);
+
+                               // If all the input was consumed, then the
+                               // input is truncated, even if the output
+                               // buffer is also full. This is because
+                               // processing the last byte of the Block
+                               // never produces output.
+                               //
+                               // NOTE: This assumption may break when new
+                               // filters are added, if the end marker of
+                               // the filter doesn't consume at least one
+                               // complete byte.
+                               if (*in_pos == in_size)
+                                       ret = LZMA_DATA_ERROR;
+                               else
+                                       ret = LZMA_BUF_ERROR;
+                       }
+
+                       // Restore the positions.
+                       *in_pos = in_start;
+                       *out_pos = out_start;
+               }
+       }
+
+       // Free the decoder memory. This needs to be done even if
+       // initialization fails, because the internal API doesn't
+       // require the initialization function to free its memory on error.
+       lzma_next_end(&block_decoder, allocator);
+
+       return ret;
+}