1 files changed, 130 insertions, 0 deletions
diff --git a/pkgs/development/tools/ocaml/opam/opam.nix.pl b/pkgs/development/tools/ocaml/opam/opam.nix.pl
new file mode 100755
index 000000000000..1862add452d6
--- /dev/null
+++ b/pkgs/development/tools/ocaml/opam/opam.nix.pl
@@ -0,0 +1,130 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings qw<all>;
+use Getopt::Std;
+
+my $gencmd = "# Generated by: " . join(" ", $0, @ARGV) . "\n";
+
+our $opt_v;
+our $opt_p;
+our $opt_r;
+our $opt_t;
+getopts "v:p:t:r:";
+
+my $OPAM_RELEASE = $opt_v // "2.0.0";
+my $OPAM_TAG = $opt_t // $OPAM_RELEASE;
+my $OPAM_GITHUB_REPO = $opt_r // "ocaml/opam";
+my $OPAM_RELEASE_URL = "https://github.com/$OPAM_GITHUB_REPO/archive/$OPAM_TAG.zip";
+my $OPAM_RELEASE_SHA256 = `nix-prefetch-url \Q$OPAM_RELEASE_URL\E`;
+chomp $OPAM_RELEASE_SHA256;
+
+my $OPAM_BASE_URL = "https://raw.githubusercontent.com/$OPAM_GITHUB_REPO/$OPAM_TAG";
+my $OPAM_OPAM = `curl -L --url \Q$OPAM_BASE_URL\E/opam-devel.opam`;
+my($OCAML_MIN_VERSION) = $OPAM_OPAM =~ /^available: ocaml-version >= "(.*)"$/m
+  or die "could not parse ocaml version bound\n";
+
+print <<"EOF";
+{ stdenv, lib, fetchurl, makeWrapper, getconf,
+  ocaml, unzip, ncurses, curl, aspcud, bubblewrap
+}:
+
+assert lib.versionAtLeast ocaml.version "$OCAML_MIN_VERSION";
+
+let
+  srcs = {
+EOF
+
+my %urls = ();
+my %md5s = ();
+
+open(SOURCES, "-|", "curl", "-L", "--url", "$OPAM_BASE_URL/src_ext/Makefile.sources");
+while (<SOURCES>) {
+  if (/^URL_(?!PKG_)([-\w]+)\s*=\s*(\S+)$/) {
+    $urls{$1} = $2;
+  } elsif (/^MD5_(?!PKG_)([-\w]+)\s*=\s*(\S+)$/) {
+    $md5s{$1} = $2;
+  }
+}
+for my $src (sort keys %urls) {
+  my ($sha256,$store_path) = split /\n/, `nix-prefetch-url --print-path \Q$urls{$src}\E`;
+  system "echo \Q$md5s{$src}\E' *'\Q$store_path\E | md5sum -c 1>&2";
+  die "md5 check failed for $urls{$src}\n" if $?;
+  print <<"EOF";
+    $src = fetchurl {
+      url = "$urls{$src}";
+      sha256 = "$sha256";
+    };
+EOF
+}
+
+print <<"EOF";
+    opam = fetchurl {
+      url = "$OPAM_RELEASE_URL";
+      sha256 = "$OPAM_RELEASE_SHA256";
+    };
+  };
+in stdenv.mkDerivation rec {
+  name = "opam-\${version}";
+  version = "$OPAM_RELEASE";
+
+  buildInputs = [ unzip curl ncurses ocaml makeWrapper getconf ] ++ lib.optional stdenv.isLinux bubblewrap;
+
+  src = srcs.opam;
+
+  postUnpack = ''
+EOF
+for my $src (sort keys %urls) {
+  my($ext) = $urls{$src} =~ /(\.(?:t(?:ar\.|)|)(?:gz|bz2?))$/
+    or die "could not find extension for $urls{$src}\n";
+  print <<"EOF";
+    ln -sv \${srcs.$src} \$sourceRoot/src_ext/$src$ext
+EOF
+}
+print <<'EOF';
+  '';
+
+EOF
+if (defined $opt_p) {
+  print "  patches = [ ";
+  for my $patch (split /[, ]/, $opt_p) {
+    $patch =~ s/^(?=[^\/]*$)/.\//;
+    print "$patch ";
+  }
+  print "];\n\n";
+}
+print <<'EOF';
+  preConfigure = ''
+    substituteInPlace ./src_ext/Makefile --replace "%.stamp: %.download" "%.stamp:"
+    patchShebangs src/state/shellscripts
+  '';
+
+  postConfigure = "make lib-ext";
+
+  # Dirty, but apparently ocp-build requires a TERM
+  makeFlags = ["TERM=screen"];
+
+  outputs = [ "out" "installer" ];
+  setOutputFlags = false;
+
+  # change argv0 to "opam" as a workaround for
+  # https://github.com/ocaml/opam/issues/2142
+  postInstall = ''
+    mv $out/bin/opam $out/bin/.opam-wrapped
+    makeWrapper $out/bin/.opam-wrapped $out/bin/opam \
+      --argv0 "opam" \
+      --suffix PATH : ${aspcud}/bin:${unzip}/bin:${curl}/bin:${lib.optionalString stdenv.isLinux "${bubblewrap}/bin:"}${getconf}/bin
+    $out/bin/opam-installer --prefix=$installer opam-installer.install
+  '';
+
+  doCheck = false;
+
+  meta = with stdenv.lib; {
+    description = "A package manager for OCaml";
+    homepage = http://opam.ocamlpro.com/;
+    maintainers = [ maintainers.henrytill ];
+    platforms = platforms.all;
+  };
+}
+EOF
+print $gencmd;