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author | Daniel Baumann <mail@daniel-baumann.ch> | 2015-11-07 15:33:57 +0000 |
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committer | Daniel Baumann <mail@daniel-baumann.ch> | 2015-11-07 15:33:57 +0000 |
commit | 86d8a187c1da626287cc436debbb5658b1884f03 (patch) | |
tree | a6de2c2105c0f6b78ec2b3a3d234636cb664da01 /dec_stdout.cc | |
parent | Adding debian version 0.9-4. (diff) | |
download | plzip-86d8a187c1da626287cc436debbb5658b1884f03.tar.xz plzip-86d8a187c1da626287cc436debbb5658b1884f03.zip |
Merging upstream version 1.0~rc1.
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
Diffstat (limited to '')
-rw-r--r-- | dec_stdout.cc | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/dec_stdout.cc b/dec_stdout.cc new file mode 100644 index 0000000..36be19b --- /dev/null +++ b/dec_stdout.cc @@ -0,0 +1,331 @@ +/* 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" +#include "file_index.h" + + +namespace { + +enum { max_packet_size = 1 << 20 }; + + +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 ocheck_counter; + unsigned owait_counter; +private: + int deliver_worker_id; // worker queue currently delivering packets + 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 omutex; + pthread_cond_t oav_or_exit; // output packet available or all workers exited + pthread_cond_t slot_av; // free output slot available + + 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 ) + : ocheck_counter( 0 ), owait_counter( 0 ), + deliver_worker_id( 0 ), + opacket_queues( workers ), num_working( workers ), + num_workers( workers ), num_slots( 8 * slots ), num_free( num_slots ) + { xinit( &omutex ); xinit( &oav_or_exit ); xinit( &slot_av ); } + + ~Packet_courier() + { xdestroy( &slot_av ); xdestroy( &oav_or_exit ); xdestroy( &omutex ); } + + void worker_finished() + { + // notify muxer when last worker exits + xlock( &omutex ); + if( --num_working == 0 ) xsignal( &oav_or_exit ); + xunlock( &omutex ); + } + + // 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; + } + + bool finished() // all packets delivered to muxer + { + if( num_free != num_slots || num_working != 0 ) return false; + for( int i = 0; i < num_workers; ++i ) + if( !opacket_queues[i].empty() ) return false; + return true; + } + }; + + +struct Worker_arg + { + const File_index * file_index; + Packet_courier * courier; + const Pretty_print * pp; + int worker_id; + int num_workers; + int infd; + }; + + + // read members from file, decompress their contents, and + // give the produced packets to courier. +extern "C" void * dworker_o( void * arg ) + { + const Worker_arg & tmp = *(Worker_arg *)arg; + const File_index & file_index = *tmp.file_index; + Packet_courier & courier = *tmp.courier; + const Pretty_print & pp = *tmp.pp; + const int worker_id = tmp.worker_id; + const int num_workers = tmp.num_workers; + const int infd = tmp.infd; + const int buffer_size = 65536; + + uint8_t * new_data = new( std::nothrow ) uint8_t[max_packet_size]; + uint8_t * const ibuffer = new( std::nothrow ) uint8_t[buffer_size]; + LZ_Decoder * const decoder = LZ_decompress_open(); + if( !new_data || !ibuffer || !decoder || + LZ_decompress_errno( decoder ) != LZ_ok ) + { pp( "Not enough memory" ); fatal(); } + int new_pos = 0; + + for( int i = worker_id; i < file_index.members(); i += num_workers ) + { + long long member_pos = file_index.mblock( i ).pos(); + long long member_rest = file_index.mblock( i ).size(); + + while( member_rest > 0 ) + { + while( LZ_decompress_write_size( decoder ) > 0 ) + { + const int size = std::min( LZ_decompress_write_size( decoder ), + (int)std::min( (long long)buffer_size, member_rest ) ); + if( size > 0 ) + { + if( preadblock( infd, ibuffer, size, member_pos ) != size ) + { pp(); show_error( "Read error", errno ); fatal(); } + member_pos += size; + member_rest -= size; + if( LZ_decompress_write( decoder, ibuffer, size ) != size ) + internal_error( "library error (LZ_decompress_write)" ); + } + if( member_rest <= 0 ) { LZ_decompress_finish( decoder ); break; } + } + while( true ) // read and pack decompressed data + { + const int rd = LZ_decompress_read( decoder, new_data + new_pos, + max_packet_size - new_pos ); + if( rd < 0 ) + fatal( decompress_read_error( decoder, pp, worker_id ) ); + new_pos += rd; + if( new_pos > max_packet_size ) + internal_error( "opacket size exceeded in worker" ); + if( new_pos == max_packet_size || + 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( LZ_decompress_finished( decoder ) == 1 ) + { + LZ_decompress_reset( decoder ); // prepare for new member + 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; + } + } + } + + delete[] ibuffer; 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(); } + courier.worker_finished(); + 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 + + 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 workers and call the muxer. +int dec_stdout( const int num_workers, const int infd, const int outfd, + const Pretty_print & pp, const int debug_level, + const File_index & file_index ) + { + const int slots_per_worker = 2; + const int num_slots = ( ( INT_MAX / num_workers >= slots_per_worker ) ? + num_workers * slots_per_worker : INT_MAX ); + + Packet_courier courier( num_workers, num_slots ); + + 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].file_index = &file_index; + worker_args[i].courier = &courier; + worker_args[i].pp = &pp; + worker_args[i].worker_id = i; + worker_args[i].num_workers = num_workers; + worker_args[i].infd = infd; + const int errcode = + pthread_create( &worker_threads[i], 0, dworker_o, &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 ) + { + const int errcode = pthread_join( worker_threads[i], 0 ); + if( errcode ) + { show_error( "Can't join worker threads", errcode ); fatal(); } + } + delete[] worker_threads; + delete[] worker_args; + + const unsigned long long in_size = file_index.file_end(); + const unsigned long long out_size = file_index.data_end(); + 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, "done\n" ); + + if( debug_level & 1 ) + std::fprintf( stderr, + "muxer tried to consume from workers %8u times\n" + "muxer had to wait %8u times\n", + courier.ocheck_counter, + courier.owait_counter ); + + if( !courier.finished() ) internal_error( "courier not finished" ); + return 0; + } |