Support parallel building in makefile buildsystem

[debhelper.git] / Debian / Debhelper / Dh_Lib.pm

diff --git a/Debian/Debhelper/Dh_Lib.pm b/Debian/Debhelper/Dh_Lib.pm
index 28a90f7bdad16b37900c7021d9b055f2d8f6388b..ebf7db7e846332e790976682d9ccc96d00f4544a 100644 (file)
--- a/Debian/Debhelper/Dh_Lib.pm
+++ b/Debian/Debhelper/Dh_Lib.pm
@@ -16,7 +16,7 @@ use vars qw(@ISA @EXPORT %dh);
            &compat &addsubstvar &delsubstvar &excludefile &package_arch
            &is_udeb &udeb_filename &debhelper_script_subst &escape_shell
            &inhibit_log &load_log &write_log &dpkg_architecture_value
-           &sourcepackage);
+           &sourcepackage &get_make_jobserver_status);
 
 my $max_compat=7;
 
@@ -175,7 +175,7 @@ sub doit {
        verbose_print(escape_shell(@_));
 
        if (! $dh{NO_ACT}) {
-               system(@_) == 0 || _error_exitcode($_[0]);
+               system(@_) == 0 || _error_exitcode(join(" ", @_));
        }
 }
 
@@ -205,6 +205,46 @@ sub _error_exitcode {
        }
 }
 
+# A helper subroutine for detecting (based on MAKEFLAGS) if make jobserver 
+# is enabled, if it is available or MAKEFLAGS contains "jobs" option.
+# It returns current status (jobserver, jobserver-unavailable or jobs-N where
+# N is number of jobs, 0 if infinite) and MAKEFLAGS cleaned up from 
+# job control options.
+sub get_make_jobserver_status {
+       my $jobsre = qr/(?:^|\s)(?:(?:-j\s*|--jobs(?:=|\s+))(\d+)?|--jobs)\b/;
+       my $status = "";
+       my $makeflags;
+
+       if (exists $ENV{MAKEFLAGS}) {
+               $makeflags = $ENV{MAKEFLAGS};
+               if ($makeflags =~ /(?:^|\s)--jobserver-fds=(\d+)/) {
+                       $status = "jobserver";
+                       if (!open(my $in, "<&", "$1")) {
+                               # Job server is unavailable
+                               $status .= "-unavailable";
+                       }
+                       else {
+                               close $in;
+                       }
+                       # Clean makeflags up
+                       $makeflags =~ s/(?:^|\s)--jobserver-fds=\S+//g;
+                       $makeflags =~ s/(?:^|\s)-j\b//g;
+               }
+               elsif (my @m = ($makeflags =~ /$jobsre/g)) {
+                       # Job count is specified in MAKEFLAGS. Whenever make reads it, a new
+                       # jobserver will be started. Job count returned is 0 if infinite.
+                       $status = "jobs-" . (defined $m[$#m] ? $m[$#m] : "0");
+                       # Clean makeflags up from "jobs" option(s)
+                       $makeflags =~ s/$jobsre//g;
+               }
+       }
+       if ($status) {
+               # MAKEFLAGS could be unset if it is empty
+               $makeflags = undef if $makeflags =~ /^\s*$/;
+       }
+       return wantarray ? ($status, $makeflags) : $status;
+}
+
 # Run a command that may have a huge number of arguments, like xargs does.
 # Pass in a reference to an array containing the arguments, and then other
 # parameters that are the command and any parameters that should be passed to
@@ -608,7 +648,7 @@ sub excludefile {
 
 sub dpkg_architecture_value {
        my $var = shift;
-       my $value=`dpkg-architecture -q$var 2>/dev/null` || error("dpkg-architecture failed");
+       my $value=`dpkg-architecture -q$var` || error("dpkg-architecture failed");
        chomp $value;
        return $value;
 }
@@ -630,10 +670,9 @@ sub dpkg_architecture_value {
        my $os;
 
        sub buildos {
-               return $os if defined $os;
-
-               $os=`dpkg-architecture -qDEB_HOST_ARCH_OS 2>/dev/null` || error("dpkg-architecture failed");
-               chomp $os;
+               if (!defined $os) {
+                       $os=dpkg_architecture_value("DEB_HOST_ARCH_OS");
+               }
                return $os;
        }
 }
@@ -668,9 +707,8 @@ sub sourcepackage {
 }
 
 # Returns a list of packages in the control file.
-# Must pass "arch" or "indep" or "same" to specify arch-dependant or
-# -independant or same arch packages. If nothing is specified, returns all
-# packages.
+# Pass "arch" or "indep" to specify arch-dependant or
+# independant. If nothing is specified, returns all packages.
 # As a side effect, populates %package_arches and %package_types with the
 # types of all packages (not only those returned).
 my (%package_types, %package_arches);
@@ -681,12 +719,6 @@ sub getpackages {
        %package_arches=();
        
        $type="" if ! defined $type;
-       
-       # Look up the build arch if we need to.
-       my $buildarch='';
-       if ($type eq 'same') {
-               $buildarch=buildarch();
-       }
 
        my $package="";
        my $arch="";
@@ -721,10 +753,12 @@ sub getpackages {
                                $package_types{$package}=$package_type;
                                $package_arches{$package}=$arch;
                        }
+
                        if ($package &&
                            (($type eq 'indep' && $arch eq 'all') ||
-                            ($type eq 'arch' && $arch ne 'all') ||
-                            ($type eq 'same' && ($arch eq 'any' || samearch($buildarch, $arch))) ||
+                            ($type eq 'arch' && ($arch eq 'any' ||
+                                            ($arch ne 'all' &&
+                                             samearch(buildarch(), $arch)))) ||
                             ! $type)) {
                                push @list, $package;
                                $package="";