Added lzma_stream_buffer_decode() and made minor cleanups.

This commit is contained in:
Lasse Collin 2009-01-23 22:27:50 +02:00
parent 0b3318661c
commit c81f13ff29
4 changed files with 144 additions and 2 deletions

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@ -471,4 +471,5 @@ extern size_t lzma_block_buffer_bound(size_t uncompressed_size);
extern lzma_ret lzma_block_buffer_encode(
lzma_block *block, lzma_allocator *allocator,
const uint8_t *in, size_t in_size,
uint8_t *out, size_t *out_pos, size_t out_size);
uint8_t *out, size_t *out_pos, size_t out_size)
lzma_attr_warn_unused_result;

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@ -222,7 +222,8 @@ extern size_t lzma_stream_buffer_bound(size_t uncompressed_size);
extern 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, size_t out_size);
uint8_t *out, size_t *out_pos, size_t out_size)
lzma_attr_warn_unused_result;
/************
@ -277,6 +278,9 @@ extern lzma_ret lzma_stream_buffer_encode(
*
* \param strm Pointer to properly prepared lzma_stream
* \param memlimit Rough memory usage limit as bytes
* \param flags Bitwise-or of zero or more of the decoder flags:
* LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK,
* LZMA_TELL_ANY_CHECK, LZMA_CONCATENATED
*
* \return - LZMA_OK: Initialization was successful.
* - LZMA_MEM_ERROR: Cannot allocate memory.
@ -319,3 +323,48 @@ extern lzma_ret lzma_auto_decoder(
*/
extern lzma_ret lzma_alone_decoder(lzma_stream *strm, uint64_t memlimit)
lzma_attr_warn_unused_result;
/**
* \brief Single-call .xz Stream decoder
*
* \param memlimit Pointer to how much memory the decoder is allowed
* to allocate. The value pointed by this pointer is
* modified if and only if LZMA_MEMLIMIT_ERROR is
* returned.
* \param flags Bitwise-or of zero or more of the decoder flags:
* LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK,
* LZMA_CONCATENATED. Note that LZMA_TELL_ANY_CHECK
* is not allowed and will return LZMA_PROG_ERROR.
* \param allocator lzma_allocator for custom allocator functions.
* Set to NULL to use malloc() and free().
* \param in Beginning of the input buffer
* \param in_pos The next byte will be read from in[*in_pos].
* *in_pos is updated only if decoding succeeds.
* \param in_size Size of the input buffer; the first byte that
* won't be read is in[in_size].
* \param out Beginning of the output buffer
* \param out_pos The next byte will be written to out[*out_pos].
* *out_pos is updated only if encoding succeeds.
* \param out_size Size of the out buffer; the first byte into
* which no data is written to is out[out_size].
*
* \return - LZMA_OK: Decoding was successful.
* - LZMA_FORMAT_ERROR
* - LZMA_OPTIONS_ERROR
* - LZMA_DATA_ERROR
* - LZMA_NO_CHECK: This can be returned only if using
* the LZMA_TELL_NO_CHECK flag.
* - LZMA_UNSUPPORTED_CHECK: This can be returned only if using
* the LZMA_TELL_UNSUPPORTED_CHECK flag.
* - LZMA_MEM_ERROR
* - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached.
* The minimum required memlimit value was stored to *memlimit.
* - LZMA_BUF_ERROR: Output buffer was too small.
* - LZMA_PROG_ERROR
*/
extern lzma_ret lzma_stream_buffer_decode(
uint64_t *memlimit, uint32_t flags, 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)
lzma_attr_warn_unused_result;

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@ -69,6 +69,7 @@ libcommon_la_SOURCES += \
filter_flags_decoder.c \
index_decoder.c \
index_hash.c \
stream_buffer_decoder.c \
stream_decoder.c \
stream_decoder.h \
stream_flags_decoder.c \

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@ -0,0 +1,91 @@
///////////////////////////////////////////////////////////////////////////////
//
/// \file stream_buffer_decoder.c
/// \brief Single-call .xz Stream decoder
//
// 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 "stream_decoder.h"
extern LZMA_API lzma_ret
lzma_stream_buffer_decode(uint64_t *memlimit, uint32_t flags,
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)
{
// Catch flags that are not allowed in buffer-to-buffer decoding.
if (flags & LZMA_TELL_ANY_CHECK)
return LZMA_PROG_ERROR;
// Initialize the Stream decoder.
// TODO: We need something to tell the decoder that it can use the
// output buffer as workspace, and thus save significant amount of RAM.
lzma_next_coder stream_decoder = LZMA_NEXT_CODER_INIT;
lzma_ret ret = lzma_stream_decoder_init(
&stream_decoder, allocator, *memlimit, flags);
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 = stream_decoder.code(stream_decoder.coder, allocator,
in, in_pos, in_size, out, out_pos, out_size,
LZMA_FINISH);
if (ret == LZMA_STREAM_END) {
ret = LZMA_OK;
} else {
// Something went wrong, restore the positions.
*in_pos = in_start;
*out_pos = out_start;
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 Stream
// never produces output.
if (*in_pos == in_size)
ret = LZMA_DATA_ERROR;
else
ret = LZMA_BUF_ERROR;
} else if (ret == LZMA_MEMLIMIT_ERROR) {
// Let the caller know how much memory would
// have been needed.
uint64_t memusage;
(void)stream_decoder.memconfig(
stream_decoder.coder,
memlimit, &memusage, 0);
}
}
}
// 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(&stream_decoder, allocator);
return ret;
}