diff options
Diffstat (limited to 'third_party/nix/src/libutil/compression.cc')
| -rw-r--r-- | third_party/nix/src/libutil/compression.cc | 432 |
1 files changed, 432 insertions, 0 deletions
diff --git a/third_party/nix/src/libutil/compression.cc b/third_party/nix/src/libutil/compression.cc new file mode 100644 index 0000000000..0dd84e3203 --- /dev/null +++ b/third_party/nix/src/libutil/compression.cc @@ -0,0 +1,432 @@ +#include "compression.hh" +#include "util.hh" +#include "finally.hh" +#include "logging.hh" + +#include <lzma.h> +#include <bzlib.h> +#include <cstdio> +#include <cstring> + +#include <brotli/decode.h> +#include <brotli/encode.h> + +#include <iostream> + +namespace nix { + +// Don't feed brotli too much at once. +struct ChunkedCompressionSink : CompressionSink +{ + uint8_t outbuf[32 * 1024]; + + void write(const unsigned char * data, size_t len) override + { + const size_t CHUNK_SIZE = sizeof(outbuf) << 2; + while (len) { + size_t n = std::min(CHUNK_SIZE, len); + writeInternal(data, n); + data += n; + len -= n; + } + } + + virtual void writeInternal(const unsigned char * data, size_t len) = 0; +}; + +struct NoneSink : CompressionSink +{ + Sink & nextSink; + NoneSink(Sink & nextSink) : nextSink(nextSink) { } + void finish() override { flush(); } + void write(const unsigned char * data, size_t len) override { nextSink(data, len); } +}; + +struct XzDecompressionSink : CompressionSink +{ + Sink & nextSink; + uint8_t outbuf[BUFSIZ]; + lzma_stream strm = LZMA_STREAM_INIT; + bool finished = false; + + XzDecompressionSink(Sink & nextSink) : nextSink(nextSink) + { + lzma_ret ret = lzma_stream_decoder( + &strm, UINT64_MAX, LZMA_CONCATENATED); + if (ret != LZMA_OK) + throw CompressionError("unable to initialise lzma decoder"); + + strm.next_out = outbuf; + strm.avail_out = sizeof(outbuf); + } + + ~XzDecompressionSink() + { + lzma_end(&strm); + } + + void finish() override + { + CompressionSink::flush(); + write(nullptr, 0); + } + + void write(const unsigned char * data, size_t len) override + { + strm.next_in = data; + strm.avail_in = len; + + while (!finished && (!data || strm.avail_in)) { + checkInterrupt(); + + lzma_ret ret = lzma_code(&strm, data ? LZMA_RUN : LZMA_FINISH); + if (ret != LZMA_OK && ret != LZMA_STREAM_END) + throw CompressionError("error %d while decompressing xz file", ret); + + finished = ret == LZMA_STREAM_END; + + if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) { + nextSink(outbuf, sizeof(outbuf) - strm.avail_out); + strm.next_out = outbuf; + strm.avail_out = sizeof(outbuf); + } + } + } +}; + +struct BzipDecompressionSink : ChunkedCompressionSink +{ + Sink & nextSink; + bz_stream strm; + bool finished = false; + + BzipDecompressionSink(Sink & nextSink) : nextSink(nextSink) + { + memset(&strm, 0, sizeof(strm)); + int ret = BZ2_bzDecompressInit(&strm, 0, 0); + if (ret != BZ_OK) + throw CompressionError("unable to initialise bzip2 decoder"); + + strm.next_out = (char *) outbuf; + strm.avail_out = sizeof(outbuf); + } + + ~BzipDecompressionSink() + { + BZ2_bzDecompressEnd(&strm); + } + + void finish() override + { + flush(); + write(nullptr, 0); + } + + void writeInternal(const unsigned char * data, size_t len) override + { + assert(len <= std::numeric_limits<decltype(strm.avail_in)>::max()); + + strm.next_in = (char *) data; + strm.avail_in = len; + + while (strm.avail_in) { + checkInterrupt(); + + int ret = BZ2_bzDecompress(&strm); + if (ret != BZ_OK && ret != BZ_STREAM_END) + throw CompressionError("error while decompressing bzip2 file"); + + finished = ret == BZ_STREAM_END; + + if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) { + nextSink(outbuf, sizeof(outbuf) - strm.avail_out); + strm.next_out = (char *) outbuf; + strm.avail_out = sizeof(outbuf); + } + } + } +}; + +struct BrotliDecompressionSink : ChunkedCompressionSink +{ + Sink & nextSink; + BrotliDecoderState * state; + bool finished = false; + + BrotliDecompressionSink(Sink & nextSink) : nextSink(nextSink) + { + state = BrotliDecoderCreateInstance(nullptr, nullptr, nullptr); + if (!state) + throw CompressionError("unable to initialize brotli decoder"); + } + + ~BrotliDecompressionSink() + { + BrotliDecoderDestroyInstance(state); + } + + void finish() override + { + flush(); + writeInternal(nullptr, 0); + } + + void writeInternal(const unsigned char * data, size_t len) override + { + const uint8_t * next_in = data; + size_t avail_in = len; + uint8_t * next_out = outbuf; + size_t avail_out = sizeof(outbuf); + + while (!finished && (!data || avail_in)) { + checkInterrupt(); + + if (!BrotliDecoderDecompressStream(state, + &avail_in, &next_in, + &avail_out, &next_out, + nullptr)) + throw CompressionError("error while decompressing brotli file"); + + if (avail_out < sizeof(outbuf) || avail_in == 0) { + nextSink(outbuf, sizeof(outbuf) - avail_out); + next_out = outbuf; + avail_out = sizeof(outbuf); + } + + finished = BrotliDecoderIsFinished(state); + } + } +}; + +ref<std::string> decompress(const std::string & method, const std::string & in) +{ + StringSink ssink; + auto sink = makeDecompressionSink(method, ssink); + (*sink)(in); + sink->finish(); + return ssink.s; +} + +ref<CompressionSink> makeDecompressionSink(const std::string & method, Sink & nextSink) +{ + if (method == "none" || method == "") + return make_ref<NoneSink>(nextSink); + else if (method == "xz") + return make_ref<XzDecompressionSink>(nextSink); + else if (method == "bzip2") + return make_ref<BzipDecompressionSink>(nextSink); + else if (method == "br") + return make_ref<BrotliDecompressionSink>(nextSink); + else + throw UnknownCompressionMethod("unknown compression method '%s'", method); +} + +struct XzCompressionSink : CompressionSink +{ + Sink & nextSink; + uint8_t outbuf[BUFSIZ]; + lzma_stream strm = LZMA_STREAM_INIT; + bool finished = false; + + XzCompressionSink(Sink & nextSink, bool parallel) : nextSink(nextSink) + { + lzma_ret ret; + bool done = false; + + if (parallel) { +#ifdef HAVE_LZMA_MT + lzma_mt mt_options = {}; + mt_options.flags = 0; + mt_options.timeout = 300; // Using the same setting as the xz cmd line + mt_options.preset = LZMA_PRESET_DEFAULT; + mt_options.filters = NULL; + mt_options.check = LZMA_CHECK_CRC64; + mt_options.threads = lzma_cputhreads(); + mt_options.block_size = 0; + if (mt_options.threads == 0) + mt_options.threads = 1; + // FIXME: maybe use lzma_stream_encoder_mt_memusage() to control the + // number of threads. + ret = lzma_stream_encoder_mt(&strm, &mt_options); + done = true; +#else + printMsg(lvlError, "warning: parallel XZ compression requested but not supported, falling back to single-threaded compression"); +#endif + } + + if (!done) + ret = lzma_easy_encoder(&strm, 6, LZMA_CHECK_CRC64); + + if (ret != LZMA_OK) + throw CompressionError("unable to initialise lzma encoder"); + + // FIXME: apply the x86 BCJ filter? + + strm.next_out = outbuf; + strm.avail_out = sizeof(outbuf); + } + + ~XzCompressionSink() + { + lzma_end(&strm); + } + + void finish() override + { + CompressionSink::flush(); + write(nullptr, 0); + } + + void write(const unsigned char * data, size_t len) override + { + strm.next_in = data; + strm.avail_in = len; + + while (!finished && (!data || strm.avail_in)) { + checkInterrupt(); + + lzma_ret ret = lzma_code(&strm, data ? LZMA_RUN : LZMA_FINISH); + if (ret != LZMA_OK && ret != LZMA_STREAM_END) + throw CompressionError("error %d while compressing xz file", ret); + + finished = ret == LZMA_STREAM_END; + + if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) { + nextSink(outbuf, sizeof(outbuf) - strm.avail_out); + strm.next_out = outbuf; + strm.avail_out = sizeof(outbuf); + } + } + } +}; + +struct BzipCompressionSink : ChunkedCompressionSink +{ + Sink & nextSink; + bz_stream strm; + bool finished = false; + + BzipCompressionSink(Sink & nextSink) : nextSink(nextSink) + { + memset(&strm, 0, sizeof(strm)); + int ret = BZ2_bzCompressInit(&strm, 9, 0, 30); + if (ret != BZ_OK) + throw CompressionError("unable to initialise bzip2 encoder"); + + strm.next_out = (char *) outbuf; + strm.avail_out = sizeof(outbuf); + } + + ~BzipCompressionSink() + { + BZ2_bzCompressEnd(&strm); + } + + void finish() override + { + flush(); + writeInternal(nullptr, 0); + } + + void writeInternal(const unsigned char * data, size_t len) override + { + assert(len <= std::numeric_limits<decltype(strm.avail_in)>::max()); + + strm.next_in = (char *) data; + strm.avail_in = len; + + while (!finished && (!data || strm.avail_in)) { + checkInterrupt(); + + int ret = BZ2_bzCompress(&strm, data ? BZ_RUN : BZ_FINISH); + if (ret != BZ_RUN_OK && ret != BZ_FINISH_OK && ret != BZ_STREAM_END) + throw CompressionError("error %d while compressing bzip2 file", ret); + + finished = ret == BZ_STREAM_END; + + if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) { + nextSink(outbuf, sizeof(outbuf) - strm.avail_out); + strm.next_out = (char *) outbuf; + strm.avail_out = sizeof(outbuf); + } + } + } +}; + +struct BrotliCompressionSink : ChunkedCompressionSink +{ + Sink & nextSink; + uint8_t outbuf[BUFSIZ]; + BrotliEncoderState *state; + bool finished = false; + + BrotliCompressionSink(Sink & nextSink) : nextSink(nextSink) + { + state = BrotliEncoderCreateInstance(nullptr, nullptr, nullptr); + if (!state) + throw CompressionError("unable to initialise brotli encoder"); + } + + ~BrotliCompressionSink() + { + BrotliEncoderDestroyInstance(state); + } + + void finish() override + { + flush(); + writeInternal(nullptr, 0); + } + + void writeInternal(const unsigned char * data, size_t len) override + { + const uint8_t * next_in = data; + size_t avail_in = len; + uint8_t * next_out = outbuf; + size_t avail_out = sizeof(outbuf); + + while (!finished && (!data || avail_in)) { + checkInterrupt(); + + if (!BrotliEncoderCompressStream(state, + data ? BROTLI_OPERATION_PROCESS : BROTLI_OPERATION_FINISH, + &avail_in, &next_in, + &avail_out, &next_out, + nullptr)) + throw CompressionError("error while compressing brotli compression"); + + if (avail_out < sizeof(outbuf) || avail_in == 0) { + nextSink(outbuf, sizeof(outbuf) - avail_out); + next_out = outbuf; + avail_out = sizeof(outbuf); + } + + finished = BrotliEncoderIsFinished(state); + } + } +}; + +ref<CompressionSink> makeCompressionSink(const std::string & method, Sink & nextSink, const bool parallel) +{ + if (method == "none") + return make_ref<NoneSink>(nextSink); + else if (method == "xz") + return make_ref<XzCompressionSink>(nextSink, parallel); + else if (method == "bzip2") + return make_ref<BzipCompressionSink>(nextSink); + else if (method == "br") + return make_ref<BrotliCompressionSink>(nextSink); + else + throw UnknownCompressionMethod(format("unknown compression method '%s'") % method); +} + +ref<std::string> compress(const std::string & method, const std::string & in, const bool parallel) +{ + StringSink ssink; + auto sink = makeCompressionSink(method, ssink, parallel); + (*sink)(in); + sink->finish(); + return ssink.s; +} + +} |