build: Include a copy of Nix's libstore and daemon; build it.

* configure.ac: Call `AC_USE_SYSTEM_EXTENSIONS', and
  `GUIX_SYSTEM_TYPE'.  Add `--with-store-dir' option, and substitute
  `storedir'.  Include `config-daemon.ac'.
* config-daemon.ac: New file.
* Makefile.am [BUILD_DAEMON]: Include `daemon.am'.
* daemon.am: New file.
* m4/guix.m4 (GUIX_SYSTEM_TYPE): New macro.

* nix/libutil/gcrypt-hash.cc, nix/libutil/gcrypt-hash.hh,
  nix/libutil/md5.h, nix/libutil/sha1.h, nix/libutil/sha256.h,
  nix/nix-daemon/guix-daemon.cc, nix/nix-daemon/shared.hh: New files.

17 files changed, 633 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index 1fe15621e2..89f0ae797c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -50,3 +50,13 @@ config.cache
 /guix-package
 /guix/config.scm
 /guix-import
+/nix/nix-daemon/nix-daemon.cc
+/nix/config.h
+/nix/config.h.in
+stamp-h[0-9]
+/nix/AUTHORS
+/nix/COPYING
+/libformat.a
+/libstore.a
+/libutil.a
+/guix-daemon
diff --git a/Makefile.am b/Makefile.am
index 8bb3b55634..7e5be0be2a 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -222,6 +222,12 @@ SUBDIRS = po
 info_TEXINFOS = doc/guix.texi
 EXTRA_DIST += doc/fdl-1.3.texi
 
+if BUILD_DAEMON
+
+include daemon.am
+
+endif BUILD_DAEMON
+
 ACLOCAL_AMFLAGS = -I m4
 AM_DISTCHECK_CONFIGURE_FLAGS =			\
   --with-libgcrypt-prefix="$(LIBGCRYPT_PREFIX)"	\
diff --git a/config-daemon.ac b/config-daemon.ac
new file mode 100644
index 0000000000..7570814705
--- /dev/null
+++ b/config-daemon.ac
@@ -0,0 +1,64 @@
+dnl -*- Autoconf -*- fragment for the C++ daemon.
+
+AC_ARG_ENABLE([daemon],
+  [AS_HELP_STRING([--enable-daemon], [build the Nix daemon (C++)])],
+  [guix_build_daemon="$enableval"],
+  [guix_build_daemon="no"])
+
+AC_MSG_CHECKING([whether to build daemon])
+AC_MSG_RESULT([$guix_build_daemon])
+
+dnl C++ environment.  This macro must be used unconditionnaly.
+AC_PROG_CXX
+
+if test "x$guix_build_daemon" = "xyes"; then
+
+  AC_PROG_RANLIB
+  AC_CONFIG_HEADER([nix/config.h])
+
+  dnl Use 64-bit file system calls so that we can support files > 2 GiB.
+  AC_SYS_LARGEFILE
+
+  dnl Look for libbz2, a required dependency.
+  AC_CHECK_LIB([bz2], [BZ2_bzWriteOpen], [true],
+    [AC_MSG_ERROR([Guix requires libbz2, which is part of bzip2.  See http://www.bzip.org/.])])
+  AC_CHECK_HEADERS([bzlib.h], [true],
+    [AC_MSG_ERROR([Guix requires libbz2, which is part of bzip2.  See http://www.bzip.org/.])])
+
+  dnl Look for SQLite, a required dependency.
+  PKG_CHECK_MODULES([SQLITE3], [sqlite3 >= 3.6.19])
+
+  AC_DEFINE([NIX_VERSION], ["0.0.0"], [Fake Nix version number.])
+  AC_DEFINE_UNQUOTED([SYSTEM], ["\"$guix_system\""],
+    [Guix host system type--i.e., platform and OS kernel tuple.])
+
+  case "$LIBGCRYPT_PREFIX" in
+    no)
+      LIBGCRYPT_CFLAGS=""
+      LIBGCRYPT_LIBS=""
+      ;;
+    *)
+      LIBGCRYPT_CFLAGS="-I$LIBGCRYPT_PREFIX/include"
+      LIBGCRYPT_LIBS="-L$LIBGCRYPT_PREFIX/lib -lgcrypt"
+      ;;
+  esac
+  AC_SUBST([LIBGCRYPT_CFLAGS])
+  AC_SUBST([LIBGCRYPT_LIBS])
+
+  save_CFLAGS="$CFLAGS"
+  save_LDFLAGS="$LDFLAGS"
+  CFLAGS="$CFLAGS $LIBGCRYPT_CFLAGS"
+  LDFLAGS="$LDFLAGS $LIBGCRYPT_LDFLAGS"
+
+  have_gcrypt=yes
+  AC_CHECK_LIB([gcrypt], [gcry_md_open], [:], [have_gcrypt=no])
+  AC_CHECK_HEADER([gcrypt.h], [:], [have_gcrypt=no])
+  if test "x$have_gcrypt" != "xyes"; then
+    AC_MSG_ERROR([GNU libgcrypt not found; please install it.])
+  fi
+
+  CFLAGS="$save_CFLAGS"
+  LDFLAGS="$save_LDFLAGS"
+fi
+
+AM_CONDITIONAL([BUILD_DAEMON], [test "x$guix_build_daemon" = "xyes"])
diff --git a/configure.ac b/configure.ac
index 65fc01857f..6c7be59895 100644
--- a/configure.ac
+++ b/configure.ac
@@ -12,13 +12,23 @@ AM_INIT_AUTOMAKE([1.11 gnu silent-rules subdir-objects \
 AC_CONFIG_SRCDIR([guix.scm])
 AC_CONFIG_MACRO_DIR([m4])
 
+dnl For the C++ code.  This must be used early.
+AC_USE_SYSTEM_EXTENSIONS
+
 AM_GNU_GETTEXT([external])
 AM_GNU_GETTEXT_VERSION([0.18.1])
 
 guilemoduledir="${datarootdir}/guile/site/2.0"
 AC_SUBST([guilemoduledir])
 
-AC_CANONICAL_HOST
+GUIX_SYSTEM_TYPE
+
+AC_ARG_WITH(store-dir,
+  AC_HELP_STRING([--with-store-dir=PATH],
+    [path of the store (defaults to /nix/store)]),
+  [storedir="$withval"],
+  [storedir="/nix/store"])
+AC_SUBST(storedir)
 
 PKG_CHECK_MODULES([GUILE], [guile-2.0])
 AC_PATH_PROG([GUILE], [guile])
@@ -83,6 +93,9 @@ AC_SUBST([LIBGCRYPT_PREFIX])
 
 GUIX_ASSERT_LIBGCRYPT_USABLE
 
+AC_CACHE_SAVE
+
+m4_include([config-daemon.ac])
 
 AC_CONFIG_FILES([Makefile
                  po/Makefile.in
diff --git a/daemon.am b/daemon.am
new file mode 100644
index 0000000000..e150e54d6b
--- /dev/null
+++ b/daemon.am
@@ -0,0 +1,152 @@
+# Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+# Copyright (C) 2012 Ludovic Courtès <ludo@gnu.org>
+#
+# This file is part of Guix.
+#
+# Guix is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or (at
+# your option) any later version.
+#
+# Guix is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+#
+# Integration of the `guix-daemon' code taken from upstream Nix.
+#
+
+BUILT_SOURCES = nix/libstore/schema.sql.hh
+CLEANFILES += $(BUILT_SOURCES)
+
+noinst_LIBRARIES = libformat.a libutil.a libstore.a
+
+libformat_a_SOURCES =				\
+  nix/boost/format/free_funcs.cc		\
+  nix/boost/format/parsing.cc			\
+  nix/boost/format/format_implementation.cc
+
+libformat_headers =				\
+  nix/boost/weak_ptr.hpp			\
+  nix/boost/throw_exception.hpp			\
+  nix/boost/checked_delete.hpp			\
+  nix/boost/shared_ptr.hpp			\
+  nix/boost/format.hpp				\
+  nix/boost/assert.hpp				\
+  nix/boost/format/macros_default.hpp		\
+  nix/boost/format/format_fwd.hpp		\
+  nix/boost/format/format_class.hpp		\
+  nix/boost/format/exceptions.hpp		\
+  nix/boost/format/group.hpp			\
+  nix/boost/format/feed_args.hpp		\
+  nix/boost/format/internals_fwd.hpp		\
+  nix/boost/format/internals.hpp		\
+  nix/boost/detail/workaround.hpp		\
+  nix/boost/detail/shared_count.hpp		\
+  nix/boost/enable_shared_from_this.hpp
+
+libformat_a_CPPFLAGS =				\
+  -I$(top_srcdir)/nix
+
+libutil_a_SOURCES =				\
+  nix/libutil/archive.cc			\
+  nix/libutil/serialise.cc			\
+  nix/libutil/immutable.cc			\
+  nix/libutil/util.cc				\
+  nix/libutil/xml-writer.cc			\
+  nix/libutil/hash.cc				\
+  nix/libutil/gcrypt-hash.cc
+
+libutil_headers =				\
+  nix/libutil/immutable.hh			\
+  nix/libutil/hash.hh				\
+  nix/libutil/serialise.hh			\
+  nix/libutil/xml-writer.hh			\
+  nix/libutil/util.hh				\
+  nix/libutil/archive.hh			\
+  nix/libutil/types.hh				\
+  nix/libutil/gcrypt-hash.hh			\
+  nix/libutil/md5.h				\
+  nix/libutil/sha1.h				\
+  nix/libutil/sha256.h
+
+libutil_a_CPPFLAGS =				\
+  -I$(top_builddir)/nix				\
+  -I$(top_srcdir)/nix/libutil			\
+  $(libformat_a_CPPFLAGS)
+
+libstore_a_SOURCES =				\
+  nix/libstore/gc.cc				\
+  nix/libstore/globals.cc			\
+  nix/libstore/misc.cc				\
+  nix/libstore/references.cc			\
+  nix/libstore/store-api.cc			\
+  nix/libstore/optimise-store.cc		\
+  nix/libstore/local-store.cc			\
+  nix/libstore/remote-store.cc			\
+  nix/libstore/build.cc				\
+  nix/libstore/pathlocks.cc			\
+  nix/libstore/derivations.cc
+
+libstore_headers =				\
+  nix/libstore/references.hh			\
+  nix/libstore/pathlocks.hh			\
+  nix/libstore/globals.hh			\
+  nix/libstore/schema.sql.hh			\
+  nix/libstore/worker-protocol.hh		\
+  nix/libstore/remote-store.hh			\
+  nix/libstore/derivations.hh			\
+  nix/libstore/misc.hh				\
+  nix/libstore/local-store.hh			\
+  nix/libstore/store-api.hh
+
+libstore_a_CPPFLAGS =				\
+  $(libutil_a_CPPFLAGS)				\
+  -I$(top_srcdir)/nix/libstore			\
+  -DNIX_STORE_DIR=\"$(storedir)\"		\
+  -DNIX_DATA_DIR=\"$(datadir)\"			\
+  -DNIX_STATE_DIR=\"$(localstatedir)/nix\"	\
+  -DNIX_LOG_DIR=\"$(localstatedir)/log/nix\"	\
+  -DNIX_CONF_DIR=\"$(sysconfdir)/nix\"		\
+  -DNIX_LIBEXEC_DIR=\"$(libexecdir)\"		\
+  -DNIX_BIN_DIR=\"$(bindir)\"			\
+  -DOPENSSL_PATH="\"FIXME--no OpenSSL support\""
+
+libstore_a_CFLAGS =				\
+  $(SQLITE3_CFLAGS) $(LIBGCRYPT_CFLAGS)
+
+bin_PROGRAMS = guix-daemon
+
+guix_daemon_SOURCES =				\
+  nix/nix-daemon/nix-daemon.cc			\
+  nix/nix-daemon/guix-daemon.cc
+
+guix_daemon_CPPFLAGS =				\
+  $(libutil_a_CPPFLAGS)				\
+  -I$(top_srcdir)/nix/libstore
+
+guix_daemon_LDADD =				\
+  libstore.a libutil.a libformat.a -lbz2	\
+  $(SQLITE3_LIBS) $(LIBGCRYPT_LIBS)
+
+
+noinst_HEADERS =						\
+  $(libformat_headers) $(libutil_headers) $(libstore_headers)
+
+nix/libstore/schema.sql.hh: nix/libstore/schema.sql
+	$(GUILE) --no-auto-compile -c				\
+	  "(use-modules (rnrs io ports))			\
+	   (call-with-output-file \"$@\"			\
+	     (lambda (out)					\
+	       (call-with-input-file \"$^\"			\
+	         (lambda (in)					\
+	           (write (get-string-all in) out)))))"
+
+EXTRA_DIST +=					\
+  nix/libstore/schema.sql			\
+  nix/AUTHORS					\
+  nix/COPYING
diff --git a/m4/guix.m4 b/m4/guix.m4
index 29f928f653..9b5184ff55 100644
--- a/m4/guix.m4
+++ b/m4/guix.m4
@@ -33,3 +33,32 @@ AC_DEFUN([GUIX_ASSERT_LIBGCRYPT_USABLE],
    if test "x$guix_cv_libgcrypt_usable_p" != "xyes"; then
      AC_MSG_ERROR([GNU libgcrypt does not appear to be usable; see `--with-libgcrypt-prefix' and `README'.])
    fi])
+
+dnl GUIX_SYSTEM_TYPE
+dnl
+dnl Determine the Guix host system type, and store it in the
+dnl `guix_system' variable.
+AC_DEFUN([GUIX_SYSTEM_TYPE], [
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  AC_ARG_WITH(system, AC_HELP_STRING([--with-system=SYSTEM],
+    [Platform identifier (e.g., `i686-linux').]),
+    [guix_system="$withval"],
+    [case "$host_cpu" in
+       i*86)
+	  machine_name="i686";;
+       amd64)
+	  machine_name="x86_64";;
+       *)
+	  machine_name="$host_cpu";;
+     esac
+
+     case "$host_os" in
+       linux-gnu*)
+	  # For backward compatibility, strip the `-gnu' part.
+	  guix_system="$machine_name-linux";;
+       *)
+	  # Strip the version number from names such as `gnu0.3',
+	  # `darwin10.2.0', etc.
+	  guix_system="$machine_name-`echo $host_os | "$SED" -e's/@<:@0-9.@:>@*$//g'`";;
+     esac])
+])
diff --git a/nix/.gitignore b/nix/.gitignore
new file mode 100644
index 0000000000..92d0520cc7
--- /dev/null
+++ b/nix/.gitignore
@@ -0,0 +1,4 @@
+*.a
+*.o
+.deps
+.dirstamp
diff --git a/nix/boost/.gitignore b/nix/boost/.gitignore
new file mode 100644
index 0000000000..1f188e3b65
--- /dev/null
+++ b/nix/boost/.gitignore
@@ -0,0 +1,3 @@
+*.hpp
+*.cpp
+*.cc
diff --git a/nix/libstore/.gitignore b/nix/libstore/.gitignore
new file mode 100644
index 0000000000..512a0d022f
--- /dev/null
+++ b/nix/libstore/.gitignore
@@ -0,0 +1,3 @@
+*.cc
+*.hh
+/schema.sql
diff --git a/nix/libutil/.gitignore b/nix/libutil/.gitignore
new file mode 100644
index 0000000000..e539428b1b
--- /dev/null
+++ b/nix/libutil/.gitignore
@@ -0,0 +1,2 @@
+*.cc
+*.hh
diff --git a/nix/libutil/gcrypt-hash.cc b/nix/libutil/gcrypt-hash.cc
new file mode 100644
index 0000000000..de7e5afc1a
--- /dev/null
+++ b/nix/libutil/gcrypt-hash.cc
@@ -0,0 +1,50 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include <gcrypt-hash.hh>
+#include <assert.h>
+
+extern "C" {
+
+void
+guix_hash_init (struct guix_hash_context *ctx, gcry_md_algo_t algo)
+{
+  gcry_error_t err;
+
+  err = gcry_md_open (&ctx->md_handle, algo, 0);
+  assert (err == GPG_ERR_NO_ERROR);
+}
+
+void
+guix_hash_update (struct guix_hash_context *ctx, const void *buffer, size_t len)
+{
+  gcry_md_write (ctx->md_handle, buffer, len);
+}
+
+void
+guix_hash_final (void *resbuf, struct guix_hash_context *ctx,
+		 gcry_md_algo_t algo)
+{
+  memcpy (resbuf, gcry_md_read (ctx->md_handle, algo),
+	  gcry_md_get_algo_dlen (algo));
+  gcry_md_close (ctx->md_handle);
+}
+
+}
diff --git a/nix/libutil/gcrypt-hash.hh b/nix/libutil/gcrypt-hash.hh
new file mode 100644
index 0000000000..1e26398540
--- /dev/null
+++ b/nix/libutil/gcrypt-hash.hh
@@ -0,0 +1,39 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* An OpenSSL-like interface to GNU libgcrypt cryptographic hash
+   functions.  */
+
+#pragma once
+#include <gcrypt.h>
+#include <unistd.h>
+
+extern "C" {
+
+struct guix_hash_context
+{
+  gcry_md_hd_t md_handle;
+};
+
+extern void guix_hash_init (struct guix_hash_context *ctx, gcry_md_algo_t algo);
+extern void guix_hash_update (struct guix_hash_context *ctx, const void *buffer,
+			      size_t len);
+extern void guix_hash_final (void *resbuf, struct guix_hash_context *ctx,
+			     gcry_md_algo_t algo);
+
+}
diff --git a/nix/libutil/md5.h b/nix/libutil/md5.h
new file mode 100644
index 0000000000..c275e381f8
--- /dev/null
+++ b/nix/libutil/md5.h
@@ -0,0 +1,35 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <gcrypt-hash.hh>
+
+#define MD5_CTX guix_hash_context
+
+static inline void
+MD5_Init (struct MD5_CTX *ctx)
+{
+  guix_hash_init (ctx, GCRY_MD_MD5);
+}
+
+#define MD5_Update guix_hash_update
+
+static inline void
+MD5_Final (void *resbuf, struct MD5_CTX *ctx)
+{
+  guix_hash_final (ctx, ctx, GCRY_MD_MD5);
+}
diff --git a/nix/libutil/sha1.h b/nix/libutil/sha1.h
new file mode 100644
index 0000000000..8af92725ea
--- /dev/null
+++ b/nix/libutil/sha1.h
@@ -0,0 +1,35 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <gcrypt-hash.hh>
+
+#define SHA_CTX guix_hash_context
+
+static inline void
+SHA1_Init (struct SHA_CTX *ctx)
+{
+  guix_hash_init (ctx, GCRY_MD_SHA1);
+}
+
+#define SHA1_Update guix_hash_update
+
+static inline void
+SHA1_Final (void *resbuf, struct SHA_CTX *ctx)
+{
+  guix_hash_final (ctx, ctx, GCRY_MD_SHA1);
+}
diff --git a/nix/libutil/sha256.h b/nix/libutil/sha256.h
new file mode 100644
index 0000000000..c436d6402c
--- /dev/null
+++ b/nix/libutil/sha256.h
@@ -0,0 +1,35 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <gcrypt-hash.hh>
+
+#define SHA256_CTX guix_hash_context
+
+static inline void
+SHA256_Init (struct SHA256_CTX *ctx)
+{
+  guix_hash_init (ctx, GCRY_MD_SHA256);
+}
+
+#define SHA256_Update guix_hash_update
+
+static inline void
+SHA256_Final (void *resbuf, struct SHA256_CTX *ctx)
+{
+  guix_hash_final (ctx, ctx, GCRY_MD_SHA256);
+}
diff --git a/nix/nix-daemon/guix-daemon.cc b/nix/nix-daemon/guix-daemon.cc
new file mode 100644
index 0000000000..43d4113493
--- /dev/null
+++ b/nix/nix-daemon/guix-daemon.cc
@@ -0,0 +1,115 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include <types.hh>
+#include "shared.hh"
+#include <globals.hh>
+
+#include <stdlib.h>
+#include <argp.h>
+
+/* Variables used by `nix-daemon.cc'.  */
+volatile ::sig_atomic_t blockInt;
+char **argvSaved;
+
+using namespace nix;
+
+/* Entry point in `nix-daemon.cc'.  */
+extern void run (Strings args);
+
+
+/* Command-line options.  */
+
+const char *argp_program_version =
+  "guix-daemon (" PACKAGE_NAME ") " PACKAGE_VERSION;
+const char *argp_program_bug_address = PACKAGE_BUGREPORT;
+
+static char doc[] =
+"guix-daemon -- perform derivation builds and store accesses\
+\v\
+This program is a daemon meant to run in the background.  It serves \
+requests sent over a Unix-domain socket.  It accesses the store, and \
+builds derivations on behalf of its clients.";
+
+#define GUIX_OPT_SYSTEM 1
+#define GUIX_OPT_DISABLE_CHROOT 2
+#define GUIX_OPT_DISABLE_LOG_COMPRESSION 3
+
+static const struct argp_option options[] =
+  {
+    { "system", GUIX_OPT_SYSTEM, "SYSTEM", 0,
+      "Assume SYSTEM as the current system type" },
+    { "build-cores", 'C', "N", 0,
+      "Use N CPU cores to build each derivation; 0 means as many as available" },
+    { "max-jobs", 'M', "N", 0,
+      "Allow at most N build jobs" },
+    { "disable-chroot", GUIX_OPT_DISABLE_CHROOT, 0, 0,
+      "Disable chroot builds" },
+    { "disable-log-compression", GUIX_OPT_DISABLE_LOG_COMPRESSION, 0, 0,
+      "Disable compression of the build logs" },
+    { 0, 0, 0, 0, 0 }
+  };
+
+/* Parse a single option. */
+static error_t
+parse_opt (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    case GUIX_OPT_DISABLE_CHROOT:
+      settings.useChroot = false;
+      break;
+    case GUIX_OPT_DISABLE_LOG_COMPRESSION:
+      settings.compressLog = false;
+      break;
+    case 'C':
+      settings.buildCores = atoi (arg);
+      break;
+    case 'M':
+      settings.maxBuildJobs = atoi (arg);
+      break;
+    case GUIX_OPT_SYSTEM:
+      settings.thisSystem = arg;
+      break;
+    default:
+      return ARGP_ERR_UNKNOWN;
+    }
+
+  return 0;
+}
+
+/* Argument parsing.  */
+static struct argp argp = { options, parse_opt, 0, doc };
+
+
+
+int
+main (int argc, char *argv[])
+{
+  Strings nothing;
+
+  settings.useChroot = true;
+  settings.processEnvironment ();
+
+  argp_parse (&argp, argc, argv, 0, 0, 0);
+
+  argvSaved = argv;
+  run (nothing);
+}
diff --git a/nix/nix-daemon/shared.hh b/nix/nix-daemon/shared.hh
new file mode 100644
index 0000000000..a03c09c036
--- /dev/null
+++ b/nix/nix-daemon/shared.hh
@@ -0,0 +1,37 @@
+/* Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+   Copyright (C) 2012  Ludovic Courtès <ludo@gnu.org>
+
+   This file is part of Guix.
+
+   Guix is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or (at
+   your option) any later version.
+
+   Guix is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Guix.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Replacement for Nix's libmain/shared.hh.  */
+
+#pragma once
+
+#include <string>
+
+#include <stdlib.h>
+#include <signal.h>
+
+static inline void
+showManPage (const char *name)
+{
+  /* This idea is evil.  Abort.  */
+  abort ();
+}
+
+extern volatile ::sig_atomic_t blockInt;
+
+extern char **argvSaved;