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Fix use of sysread

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This commit is contained in:
Eelco Dolstra 2014-07-10 21:14:34 +02:00
parent 7bb632b024
commit 42d91b079c
1 changed files with 18 additions and 6 deletions
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24
perl/lib/Nix/CopyClosure.pm
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@ -7,11 +7,24 @@ use List::Util qw(sum);
use IPC::Open2; use IPC::Open2;
sub readN {
my ($bytes, $from) = @_;
my $res = "";
while ($bytes > 0) {
my $s;
my $n = sysread($from, $s, $bytes);
die "I/O error reading from remote side\n" if !defined $n;
die "got EOF while expecting $bytes bytes from remote side\n" if !$n;
$bytes -= $n;
$res .= $s;
}
return $res;
}
sub readInt { sub readInt {
my ($from) = @_; my ($from) = @_;
my $resp; return unpack("L<x4", readN(8, $from));
sysread($from, $resp, 8) == 8 or die "did not receive valid reply from remote host\n";
return unpack("L<x4", $resp);
} }
@ -66,10 +79,9 @@ sub copyTo {
my $n = readInt($from); my $n = readInt($from);
while ($n--) { while ($n--) {
my $len = readInt($from); my $len = readInt($from);
my $s; my $s = readN($len, $from);
sysread($from, $s, $len) == $len or die;
$present{$s} = 1; $present{$s} = 1;
sysread($from, $s, 8 - $len % 8) if $len % 8; # skip padding readN(8 - $len % 8, $from) if $len % 8; # skip padding
} }
my @missing = grep { !$present{$_} } @closure; my @missing = grep { !$present{$_} } @closure;