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Diffstat (limited to 'dec_stream.cc')
| -rw-r--r-- | dec_stream.cc | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/dec_stream.cc b/dec_stream.cc new file mode 100644 index 0000000..91659da --- /dev/null +++ b/dec_stream.cc @@ -0,0 +1,520 @@ +/* Plzip - A parallel compressor compatible with lzip + Copyright (C) 2009 Laszlo Ersek. + Copyright (C) 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#define _FILE_OFFSET_BITS 64 + +#include <algorithm> +#include <cerrno> +#include <climits> +#include <csignal> +#include <cstdio> +#include <cstdlib> +#include <cstring> +#include <queue> +#include <string> +#include <vector> +#include <pthread.h> +#include <stdint.h> +#include <unistd.h> +#include <lzlib.h> + +#include "lzip.h" + + +namespace { + +enum { max_packet_size = 1 << 20 }; +unsigned long long in_size = 0; +unsigned long long out_size = 0; + + +struct Packet // data block + { + uint8_t * data; // data == 0 means end of member + int size; // number of bytes in data (if any) + }; + + +class Packet_courier // moves packets around + { +public: + unsigned icheck_counter; + unsigned iwait_counter; + unsigned ocheck_counter; + unsigned owait_counter; +private: + int receive_worker_id; // worker queue currently receiving packets + int deliver_worker_id; // worker queue currently delivering packets + Slot_tally slot_tally; // limits the number of input packets + std::vector< std::queue< Packet * > > ipacket_queues; + std::vector< std::queue< Packet * > > opacket_queues; + int num_working; // number of workers still running + const int num_workers; // number of workers + const int num_slots; // max output packets in circulation + int num_free; // remaining free output slots + pthread_mutex_t imutex; + pthread_cond_t iav_or_eof; // input packet available or splitter done + pthread_mutex_t omutex; + pthread_cond_t oav_or_exit; // output packet available or all workers exited + pthread_cond_t slot_av; // free output slot available + bool eof; // splitter done + + Packet_courier( const Packet_courier & ); // declared as private + void operator=( const Packet_courier & ); // declared as private + +public: + Packet_courier( const int workers, const int slots ) + : icheck_counter( 0 ), iwait_counter( 0 ), + ocheck_counter( 0 ), owait_counter( 0 ), + receive_worker_id( 0 ), deliver_worker_id( 0 ), + slot_tally( slots ), ipacket_queues( workers ), + opacket_queues( workers ), num_working( workers ), + num_workers( workers ), num_slots( 8 * slots ), num_free( num_slots ), + eof( false ) + { + xinit( &imutex ); xinit( &iav_or_eof ); + xinit( &omutex ); xinit( &oav_or_exit ); xinit( &slot_av ); + } + + ~Packet_courier() + { + xdestroy( &slot_av ); xdestroy( &oav_or_exit ); xdestroy( &omutex ); + xdestroy( &iav_or_eof ); xdestroy( &imutex ); + } + + // make a packet with data received from splitter + // if data == 0, move to next queue + void receive_packet( uint8_t * const data, const int size ) + { + Packet * ipacket = new Packet; + ipacket->data = data; + ipacket->size = size; + if( data ) + { in_size += size; slot_tally.get_slot(); } // wait for a free slot + xlock( &imutex ); + ipacket_queues[receive_worker_id].push( ipacket ); + xbroadcast( &iav_or_eof ); + xunlock( &imutex ); + if( !data && ++receive_worker_id >= num_workers ) + receive_worker_id = 0; + } + + // distribute a packet to a worker + Packet * distribute_packet( const int worker_id ) + { + Packet * ipacket = 0; + xlock( &imutex ); + ++icheck_counter; + while( ipacket_queues[worker_id].empty() && !eof ) + { + ++iwait_counter; + xwait( &iav_or_eof, &imutex ); + } + if( !ipacket_queues[worker_id].empty() ) + { + ipacket = ipacket_queues[worker_id].front(); + ipacket_queues[worker_id].pop(); + } + xunlock( &imutex ); + if( ipacket ) + { if( ipacket->data ) slot_tally.leave_slot(); } + else + { + // notify muxer when last worker exits + xlock( &omutex ); + if( --num_working == 0 ) xsignal( &oav_or_exit ); + xunlock( &omutex ); + } + return ipacket; + } + + // collect a packet from a worker + void collect_packet( Packet * const opacket, const int worker_id ) + { + xlock( &omutex ); + if( opacket->data ) + { + while( worker_id != deliver_worker_id && num_free <= 0 ) + xwait( &slot_av, &omutex ); + --num_free; + } + opacket_queues[worker_id].push( opacket ); + if( worker_id == deliver_worker_id ) xsignal( &oav_or_exit ); + xunlock( &omutex ); + } + + // deliver a packet to muxer + // if packet data == 0, move to next queue and wait again + Packet * deliver_packet() + { + Packet * opacket = 0; + xlock( &omutex ); + ++ocheck_counter; + while( true ) + { + while( opacket_queues[deliver_worker_id].empty() && num_working > 0 ) + { + ++owait_counter; + xwait( &oav_or_exit, &omutex ); + } + if( opacket_queues[deliver_worker_id].empty() ) break; + opacket = opacket_queues[deliver_worker_id].front(); + opacket_queues[deliver_worker_id].pop(); + if( opacket->data ) + { + if( ++num_free == 1 ) xsignal( &slot_av ); + break; + } + if( ++deliver_worker_id >= num_workers ) deliver_worker_id = 0; + xbroadcast( &slot_av ); // restart deliver_worker_id thread + delete opacket; opacket = 0; + } + xunlock( &omutex ); + return opacket; + } + + void finish() // splitter has no more packets to send + { + xlock( &imutex ); + eof = true; + xbroadcast( &iav_or_eof ); + xunlock( &imutex ); + } + + bool finished() // all packets delivered to muxer + { + if( !slot_tally.all_free() || + num_free != num_slots || !eof || num_working != 0 ) return false; + for( int i = 0; i < num_workers; ++i ) + if( !ipacket_queues[i].empty() ) return false; + for( int i = 0; i < num_workers; ++i ) + if( !opacket_queues[i].empty() ) return false; + return true; + } + }; + + +// Search forward from 'pos' for "LZIP" (Boyer-Moore algorithm) +// Return pos of found string or 'pos+size' if not found. +// +int find_magic( const uint8_t * const buffer, const int pos, const int size ) + { + const uint8_t table[256] = { + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,1,4,4,3,4,4,4,4,4,4,4,4,4,4,4,4,4,2,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, + 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4 }; + + for( int i = pos; i <= pos + size - 4; i += table[buffer[i+3]] ) + if( buffer[i] == 'L' && buffer[i+1] == 'Z' && + buffer[i+2] == 'I' && buffer[i+3] == 'P' ) + return i; // magic string found + return pos + size; + } + + +struct Splitter_arg + { + Packet_courier * courier; + const Pretty_print * pp; + int infd; + }; + + + // split data from input file into chunks and pass them to + // courier for packaging and distribution to workers. +extern "C" void * dsplitter_s( void * arg ) + { + const Splitter_arg & tmp = *(Splitter_arg *)arg; + Packet_courier & courier = *tmp.courier; + const Pretty_print & pp = *tmp.pp; + const int infd = tmp.infd; + const int hsize = 6; // header size + const int tsize = 20; // trailer size + const int buffer_size = max_packet_size; + const int base_buffer_size = tsize + buffer_size + hsize; + uint8_t * const base_buffer = new( std::nothrow ) uint8_t[base_buffer_size]; + if( !base_buffer ) { pp( "Not enough memory" ); fatal(); } + uint8_t * const buffer = base_buffer + tsize; + + int size = readblock( infd, buffer, buffer_size + hsize ) - hsize; + bool at_stream_end = ( size < buffer_size ); + if( size != buffer_size && errno ) + { pp(); show_error( "Read error", errno ); fatal(); } + if( size <= tsize ) + { pp( "Error reading member header" ); fatal(); } + if( find_magic( buffer, 0, 4 ) != 0 ) + { pp( "Bad magic number (file not in lzip format)" ); fatal(); } + + unsigned long long partial_member_size = 0; + while( true ) + { + int pos = 0; + for( int newpos = 1; newpos <= size; ++newpos ) + { + newpos = find_magic( buffer, newpos, size + 4 - newpos ); + if( newpos <= size ) + { + unsigned long long member_size = 0; + for( int i = 1; i <= 8; ++i ) + { member_size <<= 8; member_size += base_buffer[tsize+newpos-i]; } + if( partial_member_size + newpos - pos == member_size ) + { // header found + uint8_t * const data = new( std::nothrow ) uint8_t[newpos - pos]; + if( !data ) { pp( "Not enough memory" ); fatal(); } + std::memcpy( data, buffer + pos, newpos - pos ); + courier.receive_packet( data, newpos - pos ); + courier.receive_packet( 0, 0 ); // end of member token + partial_member_size = 0; + pos = newpos; + } + } + } + + if( at_stream_end ) + { + uint8_t * data = new( std::nothrow ) uint8_t[size + hsize - pos]; + if( !data ) { pp( "Not enough memory" ); fatal(); } + std::memcpy( data, buffer + pos, size + hsize - pos ); + courier.receive_packet( data, size + hsize - pos ); + courier.receive_packet( 0, 0 ); // end of member token + break; + } + if( pos < buffer_size ) + { + partial_member_size += buffer_size - pos; + uint8_t * data = new( std::nothrow ) uint8_t[buffer_size - pos]; + if( !data ) { pp( "Not enough memory" ); fatal(); } + std::memcpy( data, buffer + pos, buffer_size - pos ); + courier.receive_packet( data, buffer_size - pos ); + } + std::memcpy( base_buffer, base_buffer + buffer_size, tsize + hsize ); + size = readblock( infd, buffer + hsize, buffer_size ); + at_stream_end = ( size < buffer_size ); + if( size != buffer_size && errno ) + { pp(); show_error( "Read error", errno ); fatal(); } + } + delete[] base_buffer; + courier.finish(); // no more packets to send + return 0; + } + + +struct Worker_arg + { + Packet_courier * courier; + const Pretty_print * pp; + int worker_id; + }; + + + // consume packets from courier, decompress their contents, and + // give the produced packets to courier. +extern "C" void * dworker_s( void * arg ) + { + const Worker_arg & tmp = *(Worker_arg *)arg; + Packet_courier & courier = *tmp.courier; + const Pretty_print & pp = *tmp.pp; + const int worker_id = tmp.worker_id; + + uint8_t * new_data = new( std::nothrow ) uint8_t[max_packet_size]; + LZ_Decoder * const decoder = LZ_decompress_open(); + if( !new_data || !decoder || LZ_decompress_errno( decoder ) != LZ_ok ) + { pp( "Not enough memory" ); fatal(); } + int new_pos = 0; + bool trailing_garbage_found = false; + + while( true ) + { + const Packet * const ipacket = courier.distribute_packet( worker_id ); + if( !ipacket ) break; // no more packets to process + if( !ipacket->data ) LZ_decompress_finish( decoder ); + + int written = 0; + while( !trailing_garbage_found ) + { + if( LZ_decompress_write_size( decoder ) > 0 && written < ipacket->size ) + { + const int wr = LZ_decompress_write( decoder, ipacket->data + written, + ipacket->size - written ); + if( wr < 0 ) internal_error( "library error (LZ_decompress_write)" ); + written += wr; + if( written > ipacket->size ) + internal_error( "ipacket size exceeded in worker" ); + } + while( !trailing_garbage_found ) // read and pack decompressed data + { + const int rd = LZ_decompress_read( decoder, new_data + new_pos, + max_packet_size - new_pos ); + if( rd < 0 ) + { + if( LZ_decompress_errno( decoder ) == LZ_header_error ) + trailing_garbage_found = true; + else + fatal( decompress_read_error( decoder, pp, worker_id ) ); + } + else new_pos += rd; + if( new_pos > max_packet_size ) + internal_error( "opacket size exceeded in worker" ); + if( new_pos == max_packet_size || trailing_garbage_found || + LZ_decompress_finished( decoder ) == 1 ) + { + if( new_pos > 0 ) // make data packet + { + Packet * opacket = new Packet; + opacket->data = new_data; + opacket->size = new_pos; + courier.collect_packet( opacket, worker_id ); + new_pos = 0; + new_data = new( std::nothrow ) uint8_t[max_packet_size]; + if( !new_data ) { pp( "Not enough memory" ); fatal(); } + } + if( trailing_garbage_found || + LZ_decompress_finished( decoder ) == 1 ) + { + LZ_decompress_reset( decoder ); // prepare for new ipacket + Packet * opacket = new Packet; // end of member token + opacket->data = 0; + opacket->size = 0; + courier.collect_packet( opacket, worker_id ); + break; + } + } + if( rd == 0 ) break; + } + if( !ipacket->data || written == ipacket->size ) break; + } + if( ipacket->data ) delete[] ipacket->data; + delete ipacket; + } + + delete[] new_data; + if( LZ_decompress_member_position( decoder ) != 0 ) + { pp( "Error, some data remains in decoder" ); fatal(); } + if( LZ_decompress_close( decoder ) < 0 ) + { pp( "LZ_decompress_close failed" ); fatal(); } + return 0; + } + + + // get from courier the processed and sorted packets, and write + // their contents to the output file. +void muxer( Packet_courier & courier, const Pretty_print & pp, const int outfd ) + { + while( true ) + { + Packet * opacket = courier.deliver_packet(); + if( !opacket ) break; // queue is empty. all workers exited + + out_size += opacket->size; + + if( outfd >= 0 ) + { + const int wr = writeblock( outfd, opacket->data, opacket->size ); + if( wr != opacket->size ) + { pp(); show_error( "Write error", errno ); fatal(); } + } + delete[] opacket->data; + delete opacket; + } + } + +} // end namespace + + + // init the courier, then start the splitter and the workers and + // call the muxer. +int dec_stream( const int num_workers, const int infd, const int outfd, + const Pretty_print & pp, const int debug_level, + const bool testing ) + { + const int slots_per_worker = 2; + const int num_slots = ( ( INT_MAX / num_workers >= slots_per_worker ) ? + num_workers * slots_per_worker : INT_MAX ); + in_size = 0; + out_size = 0; + Packet_courier courier( num_workers, num_slots ); + + Splitter_arg splitter_arg; + splitter_arg.courier = &courier; + splitter_arg.pp = &pp; + splitter_arg.infd = infd; + + pthread_t splitter_thread; + int errcode = pthread_create( &splitter_thread, 0, dsplitter_s, &splitter_arg ); + if( errcode ) + { show_error( "Can't create splitter thread", errcode ); fatal(); } + + Worker_arg * worker_args = new( std::nothrow ) Worker_arg[num_workers]; + pthread_t * worker_threads = new( std::nothrow ) pthread_t[num_workers]; + if( !worker_args || !worker_threads ) + { pp( "Not enough memory" ); fatal(); } + for( int i = 0; i < num_workers; ++i ) + { + worker_args[i].courier = &courier; + worker_args[i].pp = &pp; + worker_args[i].worker_id = i; + errcode = pthread_create( &worker_threads[i], 0, dworker_s, &worker_args[i] ); + if( errcode ) + { show_error( "Can't create worker threads", errcode ); fatal(); } + } + + muxer( courier, pp, outfd ); + + for( int i = num_workers - 1; i >= 0; --i ) + { + errcode = pthread_join( worker_threads[i], 0 ); + if( errcode ) + { show_error( "Can't join worker threads", errcode ); fatal(); } + } + delete[] worker_threads; + delete[] worker_args; + + errcode = pthread_join( splitter_thread, 0 ); + if( errcode ) + { show_error( "Can't join splitter thread", errcode ); fatal(); } + + if( verbosity >= 2 && out_size > 0 && in_size > 0 ) + std::fprintf( stderr, "%6.3f:1, %6.3f bits/byte, %5.2f%% saved. ", + (double)out_size / in_size, + ( 8.0 * in_size ) / out_size, + 100.0 * ( 1.0 - ( (double)in_size / out_size ) ) ); + if( verbosity >= 3 ) + std::fprintf( stderr, "decompressed size %9llu, size %9llu. ", + out_size, in_size ); + + if( verbosity >= 1 ) std::fprintf( stderr, testing ? "ok\n" : "done\n" ); + + if( debug_level & 1 ) + std::fprintf( stderr, + "any worker tried to consume from splitter %8u times\n" + "any worker had to wait %8u times\n" + "muxer tried to consume from workers %8u times\n" + "muxer had to wait %8u times\n", + courier.icheck_counter, + courier.iwait_counter, + courier.ocheck_counter, + courier.owait_counter ); + + if( !courier.finished() ) internal_error( "courier not finished" ); + return 0; + } |