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authorDaniel Baumann <mail@daniel-baumann.ch>2015-11-07 15:33:26 +0000
committerDaniel Baumann <mail@daniel-baumann.ch>2015-11-07 15:33:26 +0000
commit4766a0fb5fc0a2ce7c865450b1f63ddc6556aa3c (patch)
tree433a0c86a57b02c6ddf97910b122d8a3abe13ac8 /dec_stdout.cc
parentAdding upstream version 0.9. (diff)
downloadplzip-4766a0fb5fc0a2ce7c865450b1f63ddc6556aa3c.tar.xz
plzip-4766a0fb5fc0a2ce7c865450b1f63ddc6556aa3c.zip
Adding upstream version 1.0~rc1.upstream/1.0_rc1
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
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+/* 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;
+ }