diff options
Diffstat (limited to 'contrib/xz/src/liblzma/subblock/subblock_decoder_helper.c')
-rw-r--r-- | contrib/xz/src/liblzma/subblock/subblock_decoder_helper.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/contrib/xz/src/liblzma/subblock/subblock_decoder_helper.c b/contrib/xz/src/liblzma/subblock/subblock_decoder_helper.c new file mode 100644 index 0000000..2a864ed --- /dev/null +++ b/contrib/xz/src/liblzma/subblock/subblock_decoder_helper.c @@ -0,0 +1,70 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file subblock_decoder_helper.c +/// \brief Helper filter for the Subblock decoder +/// +/// This filter is used to indicate End of Input for subfilters needing it. +// +// Author: Lasse Collin +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#include "subblock_decoder_helper.h" + + +struct lzma_coder_s { + const lzma_options_subblock_helper *options; +}; + + +static lzma_ret +helper_decode(lzma_coder *coder, + lzma_allocator *allocator lzma_attribute((unused)), + const uint8_t *restrict in, size_t *restrict in_pos, + size_t in_size, uint8_t *restrict out, + size_t *restrict out_pos, size_t out_size, + lzma_action action lzma_attribute((unused))) +{ + // If end_was_reached is true, we cannot have any input. + assert(!coder->options->end_was_reached || *in_pos == in_size); + + // We can safely copy as much as possible, because we are never + // given more data than a single Subblock Data field. + lzma_bufcpy(in, in_pos, in_size, out, out_pos, out_size); + + // Return LZMA_STREAM_END when instructed so by the Subblock decoder. + return coder->options->end_was_reached ? LZMA_STREAM_END : LZMA_OK; +} + + +static void +helper_end(lzma_coder *coder, lzma_allocator *allocator) +{ + lzma_free(coder, allocator); + return; +} + + +extern lzma_ret +lzma_subblock_decoder_helper_init(lzma_next_coder *next, + lzma_allocator *allocator, const lzma_filter_info *filters) +{ + // This is always the last filter in the chain. + assert(filters[1].init == NULL); + + if (next->coder == NULL) { + next->coder = lzma_alloc(sizeof(lzma_coder), allocator); + if (next->coder == NULL) + return LZMA_MEM_ERROR; + + next->code = &helper_decode; + next->end = &helper_end; + } + + next->coder->options = filters[0].options; + + return LZMA_OK; +} |