#!/usr/bin/perl

use BerkeleyDB;
use Benchmark qw(timethese);
use strict;
use warnings;

use IO::Handle;

our $iter = 5_000;
our $loops = 5;

our @pids;
our $txt = 'a' x 100;
unlink("bdb4.hash.test");

for (my $i = 0; $i <= $loops; $i++) {
	if (my $pid = fork) {
		push @pids, $pid;
	}
	else {
		# Child process
		die "cannot fork: $!" unless defined $pid;
		print "\n", "-" x 25, "\n| Iteration #$i\n", "-" x 25, "\n";

		# do some setup
		my $id_BDB4_hash;
		my $bdb4_hash;
		my $env;
		my %hash;

		sub insertBDB4_hash {
			warn "Inserting $id_BDB4_hash...\n";
			my $status = $bdb4_hash->db_put($id_BDB4_hash++, $txt);
			die "Bad exit status: $status" if $status;
		}
		
		sub selectBDB4_hash {
			my $v;
		    my $status = $bdb4_hash->db_get($id_BDB4_hash++, $v);
			warn "Bad exit status: $status" if $status;
		}

		# Set environment
		my $dbhome = ".";
		my $dberr = "err";
		$env = BerkeleyDB::Env->new(
			-Home => $dbhome,
			-ErrFile => $dberr,
			-Flags => (DB_CREATE | DB_INIT_CDB | DB_INIT_MPOOL),
		);
		if (!$env) { die "could not create env: $! '$BerkeleyDB::Error'.\n"; }

		# Open tied database
		$bdb4_hash = tie %hash, "BerkeleyDB::Hash",
		-Filename => "bdb4.hash_t.test",
		-Flags => DB_CREATE,
		-Env	  => $env,
			or die "Cannot open file bdb4.hash_t.test (iter #$i): $! $BerkeleyDB::Error\n" ;

		$id_BDB4_hash         = ($i * $iter);

		my $r = timethese(
			$iter - 1,
			{
				'I BerkeleyDB::Hash' => \&insertBDB4_hash,
			},
		);

		$id_BDB4_hash   = ($i * $iter);

		$r = timethese(
			$iter - 1,
			{
				'S BerkeleyDB::Hash' => \&selectBDB4_hash,
			},
		);

		exit;
	}
}

# wait for the children to finish
foreach my $childpid (@pids) {
  waitpid($childpid, 0);
}


# Verify integrity of files when all work is complete
print "All finished!\n\n";

my $count = $iter * ($loops + 1) - 1;
my $actual;
my $last_row;

# Print the contents of the file
tie my %bdb4_hash, "BerkeleyDB::Hash",
-Filename => "bdb4.hash_t.test",
-Flags    => DB_CREATE
	or die "Cannot open file bdb4.hash_t.test: $! $BerkeleyDB::Error\n" ;
#foreach my $k (sort {$a <=> $b} keys %bdb4_hash) {
#	print "$k -> $bdb4_hash{$k}\n";
#}
$actual = scalar keys %bdb4_hash;
$last_row = $count-1;
print "BDB4_Hash_t rows inserted (actual/attempted) = $actual / $count\n";
print <<EOF;
Results of last row ($last_row):
BerkeleyDB::Hash (T): $bdb4_hash{ $last_row }
EOF