Support building with the Perl XS bindings disabled

Since the Perl bindings require shared libraries, this is required on
platforms such as Cygwin where we do a static build.

3 files changed, 75 insertions, 3 deletions

diff --git a/perl/Makefile.am b/perl/Makefile.am
index 5c841052f143..d1f9b1c74162 100644
--- a/perl/Makefile.am
+++ b/perl/Makefile.am
@@ -2,9 +2,12 @@ PERL_MODULES = lib/Nix/Store.pm lib/Nix/Manifest.pm lib/Nix/GeneratePatches.pm l
 
 all: $(PERL_MODULES:.in=)
 
-install-exec-local: $(PERL_MODULES:.in=)
+install-exec-local: $(PERL_MODULES:.in=) install-perl-xs
 	$(INSTALL) -d $(DESTDIR)$(perllibdir)/Nix
 	$(INSTALL_DATA) $(PERL_MODULES:.in=) $(DESTDIR)$(perllibdir)/Nix
+
+if PERL_BINDINGS
+install-perl-xs:
 	$(INSTALL) -d $(DESTDIR)$(perllibdir)/auto/Nix/Store
 	ln -sfn $(pkglibdir)/libNixStore$(dynlib_suffix) $(DESTDIR)$(perllibdir)/auto/Nix/Store/Store$(dynlib_suffix)
 
@@ -25,6 +28,10 @@ AM_CXXFLAGS = \
 lib/Nix/Store.cc: lib/Nix/Store.xs
 	xsubpp $^ -output $@
 
+else
+install-perl-xs:
+endif
+
 EXTRA_DIST = $(PERL_MODULES) lib/Nix/Store.xs
 
 include ../substitute.mk
diff --git a/perl/lib/Nix/Config.pm.in b/perl/lib/Nix/Config.pm.in
index c88854daf0a8..b6d346651807 100644
--- a/perl/lib/Nix/Config.pm.in
+++ b/perl/lib/Nix/Config.pm.in
@@ -10,6 +10,8 @@ $confDir = $ENV{"NIX_CONF_DIR"} || "@sysconfdir@/nix";
 $bzip2 = $ENV{"NIX_BZIP2"} || "@bzip2@";
 $curl = "@curl@";
 
+$useBindings = "@perlbindings@" eq "yes";
+
 sub readConfig {
     my %config;
     my $config = "@sysconfdir@/nix/nix.conf";
diff --git a/perl/lib/Nix/Store.pm b/perl/lib/Nix/Store.pm
index 1ae3b04b7e6f..8312a732cdea 100644
--- a/perl/lib/Nix/Store.pm
+++ b/perl/lib/Nix/Store.pm
@@ -2,6 +2,7 @@ package Nix::Store;
 
 use strict;
 use warnings;
+use Nix::Config;
 
 require Exporter;
 
@@ -21,8 +22,70 @@ our @EXPORT = qw(
 
 our $VERSION = '0.15';
 
-require XSLoader;
-XSLoader::load('Nix::Store', $VERSION);
+sub backtick {
+    open(RES, "-|", @_) or die;
+    local $/;
+    my $res = <RES> || "";
+    close RES or die;
+    return $res;
+}
+
+if ($Nix::Config::useBindings) {
+    require XSLoader;
+    XSLoader::load('Nix::Store', $VERSION);
+} else {
+
+    # Provide slow fallbacks of some functions on platforms that don't
+    # support the Perl bindings.
+
+    use File::Temp;
+    use Fcntl qw/F_SETFD/;
+
+    sub hashFile {
+        my ($algo, $base32, $path) = @_;
+        my $res = backtick("$Nix::Config::binDir/nix-hash", "--flat", $path, "--type", $algo, $base32 ? "--base32" : ());
+        chomp $res;
+        return $res;
+    }
+    
+    sub hashPath {
+        my ($algo, $base32, $path) = @_;
+        my $res = backtick("$Nix::Config::binDir/nix-hash", $path, "--type", $algo, $base32 ? "--base32" : ());
+        chomp $res;
+        return $res;
+    }
+    
+    sub hashString {
+        my ($algo, $base32, $s) = @_;
+        my $fh = File::Temp->new();
+        print $fh $s;
+        my $res = backtick("$Nix::Config::binDir/nix-hash", $fh->filename, "--type", $algo, $base32 ? "--base32" : ());
+        chomp $res;
+        return $res;
+    }
+    
+    sub addToStore {
+        my ($srcPath, $recursive, $algo) = @_;
+        die "not implemented" if $recursive || $algo ne "sha256";
+        my $res = backtick("$Nix::Config::binDir/nix-store", "--add", $srcPath);
+        chomp $res;
+        return $res;
+    }
+    
+    sub isValidPath {
+        my ($path) = @_;
+        my $res = backtick("$Nix::Config::binDir/nix-store", "--check-validity", "--print-invalid", $path);
+        chomp $res;
+        return $res ne $path;
+    }
+    
+    sub queryPathHash {
+        my ($path) = @_;
+        my $res = backtick("$Nix::Config::binDir/nix-store", "--query", "--hash", $path);
+        chomp $res;
+        return $res;
+    }
+}
 
 1;
 __END__