X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=Debian%2FDgit.pm;h=979dd427fcf77fc332a14c2272936809f3e6fb7c;hp=e177a83950e0eb6fa8ee516f946fcb312fe00623;hb=26f2213a36af62d526a41ad96caef7f3c4aa507a;hpb=1c6183785fa3a9f6fe60a55bb9ff200963b4e791

diff --git a/Debian/Dgit.pm b/Debian/Dgit.pm
index e177a839..979dd427 100644
--- a/Debian/Dgit.pm
+++ b/Debian/Dgit.pm
@@ -5,7 +5,12 @@ package Debian::Dgit;
 use strict;
 use warnings;
 
+use Carp;
 use POSIX;
+use IO::Handle;
+use Config;
+use Digest::SHA;
+use Data::Dumper;
 
 BEGIN {
     use Exporter   ();
@@ -13,29 +18,117 @@ BEGIN {
 
     $VERSION     = 1.00;
     @ISA         = qw(Exporter);
-    @EXPORT      = qw(debiantag server_branch server_ref
-                      stat_exists git_for_each_ref
-                      $package_re $branchprefix);
-    %EXPORT_TAGS = ( policyflags => [qw()] );
-    @EXPORT_OK   = qw();
+    @EXPORT      = qw(setup_sigwarn
+                      debiantag_old server_branch server_ref
+                      stat_exists link_ltarget
+		      hashfile
+                      fail ensuredir executable_on_path
+                      waitstatusmsg failedcmd
+                      cmdoutput cmdoutput_errok
+                      git_rev_parse git_get_ref git_for_each_ref
+                      git_for_each_tag_referring is_fast_fwd
+                      $package_re $component_re $deliberately_re
+                      $branchprefix
+                      initdebug enabledebug enabledebuglevel
+                      printdebug debugcmd
+                      $debugprefix *debuglevel *DEBUG
+                      shellquote printcmd messagequote);
+    # implicitly uses $main::us
+    %EXPORT_TAGS = ( policyflags => [qw(NOFFCHECK FRESHREPO)] );
+    @EXPORT_OK   = @{ $EXPORT_TAGS{policyflags} };
 }
 
 our @EXPORT_OK;
 
 our $package_re = '[0-9a-z][-+.0-9a-z]*';
+our $component_re = '[0-9a-zA-Z][-+.0-9a-zA-Z]*';
+our $deliberately_re = "(?:TEST-)?$package_re";
 our $branchprefix = 'dgit';
 
 # policy hook exit status bits
 # see dgit-repos-server head comment for documentation
-# 1 is reserved in case something fails with `exit 1'
-sub NOFFCHECK () { return 2; }
-sub FRESHREPO () { return 4; }
-# 128 is reserved
+# 1 is reserved in case something fails with `exit 1' and to spot
+# dynamic loader, runtime, etc., failures, which report 127 or 255
+sub NOFFCHECK () { return 0x2; }
+sub FRESHREPO () { return 0x4; }
 
-sub debiantag ($) { 
-    my ($v) = @_;
+our $debugprefix;
+our $debuglevel = 0;
+
+sub setup_sigwarn () {
+    our $sigwarn_mainprocess = $$;
+    $SIG{__WARN__} = sub { 
+	die $_[0] unless getppid == $sigwarn_mainprocess;
+    };
+}
+
+sub initdebug ($) { 
+    ($debugprefix) = @_;
+    open DEBUG, ">/dev/null" or die $!;
+}
+
+sub enabledebug () {
+    open DEBUG, ">&STDERR" or die $!;
+    DEBUG->autoflush(1);
+    $debuglevel ||= 1;
+}
+    
+sub enabledebuglevel ($) {
+    my ($newlevel) = @_; # may be undef (eg from env var)
+    die if $debuglevel;
+    $newlevel //= 0;
+    $newlevel += 0;
+    return unless $newlevel;
+    $debuglevel = $newlevel;
+    enabledebug();
+}
+    
+sub printdebug {
+    print DEBUG $debugprefix, @_ or die $! if $debuglevel>0;
+}
+
+sub messagequote ($) {
+    local ($_) = @_;
+    s{\\}{\\\\}g;
+    s{\n}{\\n}g;
+    s{\x08}{\\b}g;
+    s{\t}{\\t}g;
+    s{[\000-\037\177]}{ sprintf "\\x%02x", ord $& }ge;
+    $_;
+}
+
+sub shellquote {
+    my @out;
+    local $_;
+    foreach my $a (@_) {
+	$_ = $a;
+	if (!length || m{[^-=_./:0-9a-z]}i) {
+	    s{['\\]}{'\\$&'}g;
+	    push @out, "'$_'";
+	} else {
+	    push @out, $_;
+	}
+    }
+    return join ' ', @out;
+}
+
+sub printcmd {
+    my $fh = shift @_;
+    my $intro = shift @_;
+    print $fh $intro," " or die $!;
+    print $fh shellquote @_ or die $!;
+    print $fh "\n" or die $!;
+}
+
+sub debugcmd {
+    my $extraprefix = shift @_;
+    printcmd(\*DEBUG,$debugprefix.$extraprefix,@_) if $debuglevel>0;
+}
+
+sub debiantag_old ($$) { 
+    my ($v,$distro) = @_;
     $v =~ y/~:/_%/;
-    return "debian/$v";
+    return "$distro/$v";
 }
 
 sub server_branch ($) { return "$branchprefix/$_[0]"; }
@@ -48,28 +141,175 @@ sub stat_exists ($) {
     die "stat $f: $!";
 }
 
-sub git_for_each_ref ($$) {
-    my ($pattern,$func) = @_;
+sub _us () {
+    $::us // ($0 =~ m#[^/]*$#, $&);
+}
+
+sub fail { 
+    my $s = "@_\n";
+    my $prefix = _us().": ";
+    $s =~ s/^/$prefix/gm;
+    die $s;
+}
+
+sub ensuredir ($) {
+    my ($dir) = @_; # does not create parents
+    return if mkdir $dir;
+    return if $! == EEXIST;
+    die "mkdir $dir: $!";
+}
+
+sub executable_on_path ($) {
+    my ($program) = @_;
+    return 1 if $program =~ m{/};
+    my @path = split /:/, ($ENV{PATH} // "/usr/local/bin:/bin:/usr/bin");
+    foreach my $pe (@path) {
+	my $here = "$pe/$program";
+	return $here if stat_exists $here && -x _;
+    }
+    return undef;
+}
+
+our @signames = split / /, $Config{sig_name};
+
+sub waitstatusmsg () {
+    if (!$?) {
+	return "terminated, reporting successful completion";
+    } elsif (!($? & 255)) {
+	return "failed with error exit status ".WEXITSTATUS($?);
+    } elsif (WIFSIGNALED($?)) {
+	my $signum=WTERMSIG($?);
+	return "died due to fatal signal ".
+	    ($signames[$signum] // "number $signum").
+	    ($? & 128 ? " (core dumped)" : ""); # POSIX(3pm) has no WCOREDUMP
+    } else {
+	return "failed with unknown wait status ".$?;
+    }
+}
+
+sub failedcmd {
+    # Expects $!,$? as set by close - see below.
+    # To use with system(), set $?=-1 first.
+    #
+    # Actual behaviour of perl operations:
+    #   success              $!==0       $?==0       close of piped open
+    #   program failed       $!==0       $? >0       close of piped open
+    #   syscall failure      $! >0       $?=-1       close of piped open
+    #   failure              $! >0       unchanged   close of something else
+    #   success              trashed     $?==0       system
+    #   program failed       trashed     $? >0       system
+    #   syscall failure      $! >0       unchanged   system
+    { local ($!); printcmd \*STDERR, _us().": failed command:", @_ or die $!; };
+    if ($? < 0) {
+	fail "failed to fork/exec: $!";
+    } elsif ($?) {
+	fail "subprocess ".waitstatusmsg();
+    } else {
+	fail "subprocess produced invalid output";
+    }
+}
+
+sub cmdoutput_errok {
+    confess Dumper(\@_)." ?" if grep { !defined } @_;
+    debugcmd "|",@_;
+    open P, "-|", @_ or die "$_[0] $!";
+    my $d;
+    $!=0; $?=0;
+    { local $/ = undef; $d = <P>; }
+    die $! if P->error;
+    if (!close P) { printdebug "=>!$?\n"; return undef; }
+    chomp $d;
+    if ($debuglevel > 0) {
+	$d =~ m/^.*/;
+	my $dd = $&;
+	my $more = (length $' ? '...' : ''); #');
+	$dd =~ s{[^\n -~]|\\}{ sprintf "\\x%02x", ord $& }ge;
+	printdebug "=> \`$dd'",$more,"\n";
+    }
+    return $d;
+}
+
+sub cmdoutput {
+    my $d = cmdoutput_errok @_;
+    defined $d or failedcmd @_;
+    return $d;
+}
+
+sub link_ltarget ($$) {
+    my ($old,$new) = @_;
+    lstat $old or return undef;
+    if (-l _) {
+	$old = cmdoutput qw(realpath  --), $old;
+    }
+    link $old, $new or die "link $old $new: $!";
+}
+
+sub hashfile ($) {
+    my ($fn) = @_;
+    my $h = Digest::SHA->new(256);
+    $h->addfile($fn);
+    return $h->hexdigest();
+}
+
+sub git_rev_parse ($) {
+    return cmdoutput qw(git rev-parse), "$_[0]~0";
+}
+
+sub git_for_each_ref ($$;$) {
+    my ($pattern,$func,$gitdir) = @_;
     # calls $func->($objid,$objtype,$fullrefname,$reftail);
-    # $reftail is RHS of ref after refs/\w+/
+    # $reftail is RHS of ref after refs/[^/]+/
     # breaks if $pattern matches any ref `refs/blah' where blah has no `/'
-    my $fh = new IO::File "-|", qw(git for-each-ref), $pattern or die $!;
-    while (<$fh>) {
-	m#^(\w+)\s+(\w+)\s+(refs/\w+/(\S+))\s# or die "$_ ?";
+    my @cmd = (qw(git for-each-ref), $pattern);
+    if (defined $gitdir) {
+	@cmd = ('sh','-ec','cd "$1"; shift; exec "$@"','x', $gitdir, @cmd);
+    }
+    open GFER, "-|", @cmd or die $!;
+    debugcmd "|", @cmd;
+    while (<GFER>) {
+	chomp or die "$_ ?";
+	printdebug "|> ", $_, "\n";
+	m#^(\w+)\s+(\w+)\s+(refs/[^/]+/(\S+))$# or die "$_ ?";
 	$func->($1,$2,$3,$4);
     }
-    $!=0; $?=0; close $fh or die "$pattern $? $!";
+    $!=0; $?=0; close GFER or die "$pattern $? $!";
+}
+
+sub git_get_ref ($) {
+    # => '' if no such ref
+    my ($refname) = @_;
+    local $_ = $refname;
+    s{^refs/}{[r]efs/} or die "$refname $_ ?";
+    return cmdoutput qw(git for-each-ref --format=%(objectname)), $_;
 }
 
 sub git_for_each_tag_referring ($$) {
     my ($objreferring, $func) = @_;
-    # calls $func->($objid,$fullrefname,$tagname);
+    # calls $func->($tagobjid,$refobjid,$fullrefname,$tagname);
+    printdebug "git_for_each_tag_referring ",
+        ($objreferring // 'UNDEF'),"\n";
     git_for_each_ref('refs/tags', sub {
-	my ($objid,$objtype,$fullrefname,$tagname) = @_;
-	next unless $objtype eq 'tag';
-	next if defined $objreferring and $objid ne $objreferring;
-	$func->($objid,$fullrefname,$tagname);
+	my ($tagobjid,$objtype,$fullrefname,$tagname) = @_;
+	return unless $objtype eq 'tag';
+	my $refobjid = git_rev_parse $tagobjid;
+	return unless
+	    !defined $objreferring # caller wants them all
+	    or $tagobjid eq $objreferring
+	    or $refobjid eq $objreferring;
+	$func->($tagobjid,$refobjid,$fullrefname,$tagname);
     });
 }
 
+sub is_fast_fwd ($$) {
+    my ($ancestor,$child) = @_;
+    my @cmd = (qw(git merge-base), $ancestor, $child);
+    my $mb = cmdoutput_errok @cmd;
+    if (defined $mb) {
+	return git_rev_parse($mb) eq git_rev_parse($ancestor);
+    } else {
+	$?==256 or failedcmd @cmd;
+	return 0;
+    }
+}
+
 1;