Move version build system module to separate library

14 files changed, 5 insertions, 1248 deletions

diff --git a/build2/b.cxx b/build2/b.cxx
index 907784b..a016278 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -52,7 +52,7 @@
 #include <libbuild2/install/init.hxx>
 
 #include <libbuild2/in/init.hxx>
-#include <build2/version/init.hxx>
+#include <libbuild2/version/init.hxx>
 
 #include <build2/bin/init.hxx>
 #include <build2/c/init.hxx>
@@ -449,8 +449,7 @@ main (int argc, char* argv[])
       reg (&test::build2_test_load);
       reg (&install::build2_install_load);
 
-      bm["version"] = mf {"version", &version::boot, &version::init};
-
+      reg (&version::build2_version_load);
       reg (&in::build2_in_load);
 
       bm["bin.vars"] = mf {"bin.vars", nullptr, &bin::vars_init};
diff --git a/build2/bash/init.cxx b/build2/bash/init.cxx
index a23bc61..146e680 100644
--- a/build2/bash/init.cxx
+++ b/build2/bash/init.cxx
@@ -36,7 +36,7 @@ namespace build2
       tracer trace ("bash::init");
       l5 ([&]{trace << "for " << bs;});
 
-      // Load in.base (in.* varibales, in{} target type).
+      // Load in.base (in.* variables, in{} target type).
       //
       if (!cast_false<bool> (rs["in.base.loaded"]))
         load_module (rs, rs, "in.base", l);
diff --git a/build2/buildfile b/build2/buildfile
index a940793..ea39e87 100644
--- a/build2/buildfile
+++ b/build2/buildfile
@@ -8,9 +8,9 @@ import libs += libpkgconf%lib{pkgconf}
 include ../libbuild2/
 libs += ../libbuild2/lib{build2}
 
-for m: in
+for m: version in
 {
-  include ../libbuild2/in/
+  include ../libbuild2/$m/
   libs += ../libbuild2/$m/lib{build2-$m}
 }
 
diff --git a/build2/version/init.cxx b/build2/version/init.cxx
deleted file mode 100644
index 30f0f45..0000000
--- a/build2/version/init.cxx
+++ /dev/null
@@ -1,392 +0,0 @@
-// file      : build2/version/init.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <build2/version/init.hxx>
-
-#include <libbutl/manifest-parser.mxx>
-
-#include <libbuild2/scope.hxx>
-#include <libbuild2/context.hxx>
-#include <libbuild2/variable.hxx>
-#include <libbuild2/diagnostics.hxx>
-
-#include <libbuild2/config/utility.hxx>
-
-#include <libbuild2/dist/module.hxx>
-
-#include <build2/version/rule.hxx>
-#include <build2/version/module.hxx>
-#include <build2/version/utility.hxx>
-#include <build2/version/snapshot.hxx>
-
-using namespace std;
-using namespace butl;
-
-namespace build2
-{
-  namespace version
-  {
-    static const path manifest_file ("manifest");
-
-    static const in_rule in_rule_;
-    static const manifest_install_rule manifest_install_rule_;
-
-    bool
-    boot (scope& rs, const location& l, unique_ptr<module_base>& mod)
-    {
-      tracer trace ("version::boot");
-      l5 ([&]{trace << "for " << rs;});
-
-      // Extract the version from the manifest file. As well as summary and
-      // url while at it.
-      //
-      // Also, as a sanity check, verify the package name matches the build
-      // system project name.
-      //
-      string sum;
-      string url;
-
-      standard_version v;
-      dependencies ds;
-      {
-        path f (rs.src_path () / manifest_file);
-
-        try
-        {
-          if (!file_exists (f))
-            fail (l) << "no manifest file in " << rs.src_path ();
-
-          ifdstream ifs (f);
-          manifest_parser p (ifs, f.string ());
-
-          manifest_name_value nv (p.next ());
-          if (!nv.name.empty () || nv.value != "1")
-            fail (l) << "unsupported manifest format in " << f;
-
-          for (nv = p.next (); !nv.empty (); nv = p.next ())
-          {
-            if (nv.name == "name")
-            {
-              auto& pn (cast<project_name> (rs.vars[var_project]));
-
-              if (nv.value != pn.string ())
-              {
-                path bf (rs.src_path () / rs.root_extra->bootstrap_file);
-                location ml (&f, nv.value_line, nv.value_column);
-                location bl (&bf);
-
-                fail (ml) << "package name " << nv.value << " does not match "
-                          << "build system project name " << pn <<
-                  info (bl) << "build system project name specified here";
-              }
-            }
-            if (nv.name == "summary")
-              sum = move (nv.value);
-            else if (nv.name == "url")
-              url = move (nv.value);
-            else if (nv.name == "version")
-            {
-              try
-              {
-                // Allow the package stub versions in the 0+<revision> form.
-                // While not standard, we want to use the version module for
-                // packaging stubs.
-                //
-                v = standard_version (nv.value, standard_version::allow_stub);
-              }
-              catch (const invalid_argument& e)
-              {
-                fail << "invalid standard version '" << nv.value << "': " << e;
-              }
-            }
-            else if (nv.name == "depends")
-            {
-              // According to the package manifest spec, the format of the
-              // 'depends' value is as follows:
-              //
-              // depends: [?][*] <alternatives> [; <comment>]
-              //
-              // <alternatives> := <dependency> [ '|' <dependency>]*
-              // <dependency>   := <name> [<constraint>]
-              // <constraint>   := <comparison> | <range>
-              // <comparison>   := ('==' | '>' | '<' | '>=' | '<=') <version>
-              // <range>        := ('(' | '[') <version> <version> (')' | ']')
-              //
-              // Note that we don't do exhaustive validation here leaving it
-              // to the package manager.
-              //
-              string v (move (nv.value));
-
-              size_t p;
-
-              // Get rid of the comment.
-              //
-              if ((p = v.find (';')) != string::npos)
-                v.resize (p);
-
-              // Get rid of conditional/runtime markers. Note that enither of
-              // them is valid in the rest of the value.
-              //
-              if ((p = v.find_last_of ("?*")) != string::npos)
-                v.erase (0, p + 1);
-
-              // Parse as |-separated "words".
-              //
-              for (size_t b (0), e (0); next_word (v, b, e, '|'); )
-              {
-                string d (v, b, e - b);
-                trim (d);
-
-                p = d.find_first_of (" \t=<>[(~^");
-                string n (d, 0, p);
-                string c (p != string::npos ? string (d, p) : string ());
-
-                trim (n);
-                trim (c);
-
-                try
-                {
-                  package_name pn (move (n));
-                  string v (pn.variable ());
-
-                  ds.emplace (move (v), dependency {move (pn), move (c)});
-                }
-                catch (const invalid_argument& e)
-                {
-                  fail (l) << "invalid package name for dependency "
-                           << d << ": " << e;
-                }
-              }
-            }
-          }
-        }
-        catch (const manifest_parsing& e)
-        {
-          location l (&f, e.line, e.column);
-          fail (l) << e.description;
-        }
-        catch (const io_error& e)
-        {
-          fail (l) << "unable to read from " << f << ": " << e;
-        }
-        catch (const system_error& e) // EACCES, etc.
-        {
-          fail (l) << "unable to access manifest " << f << ": " << e;
-        }
-
-        if (v.empty ())
-          fail (l) << "no version in " << f;
-      }
-
-      // If this is the latest snapshot (i.e., the -a.1.z kind), then load the
-      // snapshot number and id (e.g., commit date and id from git).
-      //
-      bool committed (true);
-      bool rewritten (false);
-      if (v.snapshot () && v.snapshot_sn == standard_version::latest_sn)
-      {
-        snapshot ss (extract_snapshot (rs));
-
-        if (!ss.empty ())
-        {
-          v.snapshot_sn = ss.sn;
-          v.snapshot_id = move (ss.id);
-          committed = ss.committed;
-          rewritten = true;
-        }
-        else
-          committed = false;
-      }
-
-      // If there is a dependency on the build system itself, check it (so
-      // there is no need for explicit using build@X.Y.Z).
-      //
-      {
-        auto i (ds.find ("build2"));
-
-        if (i != ds.end () && !i->second.constraint.empty ())
-        try
-        {
-          check_build_version (
-            standard_version_constraint (i->second.constraint, v), l);
-        }
-        catch (const invalid_argument& e)
-        {
-          fail (l) << "invalid version constraint for dependency build2 "
-                   << i->second.constraint << ": " << e;
-        }
-      }
-
-      // Set all the version.* variables.
-      //
-      auto& vp (var_pool.rw (rs));
-
-      auto set = [&vp, &rs] (const char* var, auto val)
-      {
-        using T = decltype (val);
-        auto& v (vp.insert<T> (var, variable_visibility::project));
-        rs.assign (v) = move (val);
-      };
-
-      if (!sum.empty ()) rs.assign (var_project_summary) = move (sum);
-      if (!url.empty ()) rs.assign (var_project_url)     = move (url);
-
-      set ("version", v.string ());  // Project version (var_version).
-
-      set ("version.project",        v.string_project ());
-      set ("version.project_number", v.version);
-
-      // Enough of project version for unique identification (can be used in
-      // places like soname, etc).
-      //
-      set ("version.project_id",     v.string_project_id ());
-
-      set ("version.stub", v.stub ()); // bool
-
-      set ("version.epoch", uint64_t (v.epoch));
-
-      set ("version.major", uint64_t (v.major ()));
-      set ("version.minor", uint64_t (v.minor ()));
-      set ("version.patch", uint64_t (v.patch ()));
-
-      optional<uint16_t> a (v.alpha ());
-      optional<uint16_t> b (v.beta ());
-
-      set ("version.alpha",              a.has_value ());
-      set ("version.beta",               b.has_value ());
-      set ("version.pre_release",        v.pre_release ().has_value ());
-      set ("version.pre_release_string", v.string_pre_release ());
-      set ("version.pre_release_number", uint64_t (a ? *a : b ? *b : 0));
-
-      set ("version.snapshot",           v.snapshot ()); // bool
-      set ("version.snapshot_sn",        v.snapshot_sn); // uint64
-      set ("version.snapshot_id",        v.snapshot_id); // string
-      set ("version.snapshot_string",    v.string_snapshot ());
-      set ("version.snapshot_committed", committed);     // bool
-
-      set ("version.revision", uint64_t (v.revision));
-
-      // Create the module.
-      //
-      mod.reset (new module (cast<project_name> (rs.vars[var_project]),
-                             move (v),
-                             committed,
-                             rewritten,
-                             move (ds)));
-
-      return true; // Init first (dist.package, etc).
-    }
-
-    static void
-    dist_callback (const path&, const scope&, void*);
-
-    bool
-    init (scope& rs,
-          scope&,
-          const location& l,
-          unique_ptr<module_base>& mod,
-          bool first,
-          bool,
-          const variable_map&)
-    {
-      tracer trace ("version::init");
-
-      if (!first)
-        fail (l) << "multiple version module initializations";
-
-      // Load in.base (in.* varibales, in{} target type).
-      //
-      if (!cast_false<bool> (rs["in.base.loaded"]))
-        load_module (rs, rs, "in.base", l);
-
-      module& m (static_cast<module&> (*mod));
-      const standard_version& v (m.version);
-
-      // If the dist module is used, set its dist.package and register the
-      // post-processing callback.
-      //
-      if (auto* dm = rs.lookup_module<dist::module> (dist::module::name))
-      {
-        // Make sure dist is init'ed, not just boot'ed.
-        //
-        if (!cast_false<bool> (rs["dist.loaded"]))
-          load_module (rs, rs, "dist", l);
-
-        m.dist_uncommitted = cast_false<bool> (rs["config.dist.uncommitted"]);
-
-        // Don't touch if dist.package was set by the user.
-        //
-        value& val (rs.assign (dm->var_dist_package));
-
-        if (!val)
-        {
-          string p (cast<project_name> (rs.vars[var_project]).string ());
-          p += '-';
-          p += v.string ();
-          val = move (p);
-
-          // Only register the post-processing callback if this is a rewritten
-          // snapshot.
-          //
-          if (m.rewritten)
-            dm->register_callback (dir_path (".") / manifest_file,
-                                   &dist_callback,
-                                   &m);
-        }
-      }
-
-      // Register rules.
-      //
-      {
-        auto& r (rs.rules);
-
-        r.insert<file> (perform_update_id,   "version.in", in_rule_);
-        r.insert<file> (perform_clean_id,    "version.in", in_rule_);
-        r.insert<file> (configure_update_id, "version.in", in_rule_);
-
-        if (cast_false<bool> (rs["install.booted"]))
-        {
-          r.insert<manifest> (
-            perform_install_id, "version.manifest", manifest_install_rule_);
-        }
-      }
-
-      return true;
-    }
-
-    static void
-    dist_callback (const path& f, const scope& rs, void* data)
-    {
-      module& m (*static_cast<module*> (data));
-
-      // Complain if this is an uncommitted snapshot.
-      //
-      if (!m.committed && !m.dist_uncommitted)
-        fail << "distribution of uncommitted project " << rs.src_path () <<
-          info << "specify config.dist.uncommitted=true to force";
-
-      // The plan is simple: fixing up the version in a temporary file then
-      // move it to the original.
-      //
-      try
-      {
-        auto_rmfile t (fixup_manifest (f,
-                                       path::temp_path ("manifest"),
-                                       m.version));
-
-        mvfile (t.path, f, (cpflags::overwrite_content |
-                            cpflags::overwrite_permissions));
-        t.cancel ();
-      }
-      catch (const io_error& e)
-      {
-        fail << "unable to overwrite " << f << ": " << e;
-      }
-      catch (const system_error& e) // EACCES, etc.
-      {
-        fail << "unable to overwrite " << f << ": " << e;
-      }
-    }
-  }
-}
diff --git a/build2/version/init.hxx b/build2/version/init.hxx
deleted file mode 100644
index ef3688a..0000000
--- a/build2/version/init.hxx
+++ /dev/null
@@ -1,31 +0,0 @@
-// file      : build2/version/init.hxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_VERSION_INIT_HXX
-#define BUILD2_VERSION_INIT_HXX
-
-#include <libbuild2/types.hxx>
-#include <libbuild2/utility.hxx>
-
-#include <libbuild2/module.hxx>
-
-namespace build2
-{
-  namespace version
-  {
-    bool
-    boot (scope&, const location&, unique_ptr<module_base>&);
-
-    bool
-    init (scope&,
-          scope&,
-          const location&,
-          unique_ptr<module_base>&,
-          bool,
-          bool,
-          const variable_map&);
-  }
-}
-
-#endif // BUILD2_VERSION_INIT_HXX
diff --git a/build2/version/module.cxx b/build2/version/module.cxx
deleted file mode 100644
index 1811cfc..0000000
--- a/build2/version/module.cxx
+++ /dev/null
@@ -1,15 +0,0 @@
-// file      : build2/version/module.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <build2/version/module.hxx>
-
-using namespace std;
-
-namespace build2
-{
-  namespace version
-  {
-    const string module::name ("version");
-  }
-}
diff --git a/build2/version/module.hxx b/build2/version/module.hxx
deleted file mode 100644
index d2b681c..0000000
--- a/build2/version/module.hxx
+++ /dev/null
@@ -1,64 +0,0 @@
-// file      : build2/version/module.hxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_VERSION_MODULE_HXX
-#define BUILD2_VERSION_MODULE_HXX
-
-#include <map>
-
-#include <libbuild2/types.hxx>
-#include <libbuild2/utility.hxx>
-
-#include <libbuild2/module.hxx>
-
-namespace build2
-{
-  namespace version
-  {
-    // A map of package names sanitized for use in variable names to the
-    // 'depends' values from manifest.
-    //
-    using package_name = project_name;
-
-    struct dependency
-    {
-      package_name name;
-      string constraint;
-    };
-
-    using dependencies = std::map<string, dependency>;
-
-    struct module: module_base
-    {
-      using dependencies_type = version::dependencies;
-
-      static const string name;
-
-      // The project variable value sanitized for use in variable names.
-      //
-      const string project;
-
-      butl::standard_version version;
-      bool committed; // Whether this is a committed snapshot.
-      bool rewritten; // Whether this is a rewritten .z snapshot.
-
-      dependencies_type dependencies;
-
-      bool dist_uncommitted = false;
-
-      module (const project_name& p,
-              butl::standard_version v,
-              bool c,
-              bool r,
-              dependencies_type d)
-          : project (p.variable ()),
-            version (move (v)),
-            committed (c),
-            rewritten (r),
-            dependencies (move (d)) {}
-    };
-  }
-}
-
-#endif // BUILD2_VERSION_MODULE_HXX
diff --git a/build2/version/rule.cxx b/build2/version/rule.cxx
deleted file mode 100644
index f110e3e..0000000
--- a/build2/version/rule.cxx
+++ /dev/null
@@ -1,334 +0,0 @@
-// file      : build2/version/rule.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <build2/version/rule.hxx>
-
-#include <libbuild2/scope.hxx>
-#include <libbuild2/target.hxx>
-#include <libbuild2/diagnostics.hxx>
-
-#include <libbuild2/in/target.hxx>
-
-#include <build2/version/module.hxx>
-#include <build2/version/utility.hxx>
-
-using namespace std;
-using namespace butl;
-
-namespace build2
-{
-  namespace version
-  {
-    using in::in;
-
-    // Return true if this prerequisite is a project's manifest file. To be
-    // sure we would need to search it into target but that we can't do in
-    // match().
-    //
-    static inline bool
-    manifest_prerequisite (const scope& rs, const prerequisite_member& p)
-    {
-      if (!p.is_a<manifest> () || p.name () != "manifest")
-        return false;
-
-      const scope& s (p.scope ());
-
-      if (s.root_scope () == nullptr) // Out of project prerequisite.
-        return false;
-
-      dir_path d (p.dir ());
-      if (d.relative ())
-        d = s.src_path () / d;
-      d.normalize ();
-
-      return d == rs.src_path ();
-    }
-
-    // in_rule
-    //
-    bool in_rule::
-    match (action a, target& xt, const string&) const
-    {
-      tracer trace ("version::in_rule::match");
-
-      file& t (static_cast<file&> (xt));
-      const scope& rs (t.root_scope ());
-
-      bool fm (false); // Found manifest.
-      bool fi (false); // Found in.
-      for (prerequisite_member p: group_prerequisite_members (a, t))
-      {
-        if (include (a, t, p) != include_type::normal) // Excluded/ad hoc.
-          continue;
-
-        fm = fm || manifest_prerequisite (rs, p);
-        fi = fi || p.is_a<in> ();
-      }
-
-      // Note that while normally we print these at verbosity level 4, these
-      // ones get quite noisy since we try this rule any file target.
-      //
-      if (!fm)
-        l5 ([&]{trace << "no manifest prerequisite for target " << t;});
-
-      if (!fi)
-        l5 ([&]{trace << "no in file prerequisite for target " << t;});
-
-      bool r (fm && fi);
-
-      // If we match, lookup and cache the module for the update operation.
-      //
-      if (r && a == perform_update_id)
-        t.data (rs.lookup_module<module> (module::name));
-
-      return r;
-    }
-
-    string in_rule::
-    lookup (const location& l,
-            action a,
-            const target& t,
-            const string& n) const
-    {
-      // Note that this code will be executed during up-to-date check for each
-      // substitution so let's try not to do anything overly sub-optimal here.
-      //
-      const module& m (*t.data<const module*> ());
-
-      // Split it into the package name and the variable/condition name.
-      //
-      // We used to bail if there is no package component but now we treat it
-      // the same as project. This can be useful when trying to reuse existing
-      // .in files (e.g., from autoconf, etc).
-      //
-      size_t p (n.find ('.'));
-
-      if (p == string::npos || n.compare (0, p, m.project) == 0)
-      {
-        return rule::lookup (l, // Standard lookup.
-                             a,
-                             t,
-                             p == string::npos ? n : string (n, p + 1));
-      }
-
-      string pn (n, 0, p);
-      string vn (n, p + 1);
-
-      // Perform substitutions for a dependency. Here we recognize the
-      // following substitutions:
-      //
-      // $libfoo.version$               - textual version constraint.
-      // $libfoo.condition(VER[,SNAP])$ - numeric satisfaction condition.
-      // $libfoo.check(VER[,SNAP])$     - numeric satisfaction check (#if ...).
-      //
-      // Where VER is the version number macro and SNAP is the optional
-      // snapshot number macro (only needed if you plan to include snapshot
-      // informaton in your constraints).
-      //
-      // Note also that the last two (condition and check) can only be used in
-      // the strict substitution mode since in::rule::substitute() will skip
-      // them in the lax mode.
-
-      // For now we re-parse the constraint every time. Firstly because not
-      // all of them are necessarily in the standard form and secondly because
-      // of the MT-safety.
-      //
-      standard_version_constraint dc;
-      const package_name* dn;
-      {
-        auto i (m.dependencies.find (pn));
-
-        if (i == m.dependencies.end ())
-          fail (l) << "unknown dependency '" << pn << "'";
-
-        const dependency& dp (i->second);
-
-        if (dp.constraint.empty ())
-          fail (l) << "no version constraint for dependency " << dp.name;
-
-        try
-        {
-          dc = standard_version_constraint (dp.constraint, m.version);
-        }
-        catch (const invalid_argument& e)
-        {
-          fail (l) << "invalid version constraint for dependency " << dp.name
-                   << " " << dp.constraint << ": " << e;
-        }
-
-        dn = &dp.name;
-      }
-
-      // Now substitute.
-      //
-      size_t i;
-      if (vn == "version")
-      {
-        return dc.string (); // Use normalized representation.
-      }
-      if (vn.compare (0, (i = 6),  "check(")     == 0 ||
-          vn.compare (0, (i = 10), "condition(") == 0)
-      {
-        size_t j (vn.find_first_of (",)", i));
-
-        if (j == string::npos || (vn[j] == ',' && vn.back () != ')'))
-          fail (l) << "missing closing ')'";
-
-        string vm (vn, i, j - i); // VER macro.
-        string sm (vn[j] == ','   // SNAP macro.
-                   ? string (vn, j + 1, vn.size () - j - 2)
-                   : string ());
-
-        trim (vm);
-        trim (sm);
-
-        auto cond = [&l, &dc, &vm, &sm] () -> string
-        {
-          auto& miv (dc.min_version);
-          auto& mav (dc.max_version);
-
-          bool mio (dc.min_open);
-          bool mao (dc.max_open);
-
-          if (sm.empty () &&
-              ((miv && miv->snapshot ()) ||
-               (mav && mav->snapshot ())))
-            fail (l) << "snapshot macro required for " << dc.string ();
-
-          auto cmp = [] (const string& m, const char* o, uint64_t v)
-          {
-            return m + o + to_string (v) + "ULL";
-          };
-
-          // Note that version orders everything among pre-releases (that E
-          // being 0/1). So the snapshot comparison is only necessary "inside"
-          // the same pre-release.
-          //
-          auto max_cmp = [&vm, &sm, mao, &mav, &cmp] (bool p = false)
-          {
-            string r;
-
-            if (mav->snapshot ())
-            {
-              r += (p ? "(" : "");
-
-              r += cmp (vm, " < ", mav->version) + " || (";
-              r += cmp (vm, " == ", mav->version) + " && ";
-              r += cmp (sm, (mao ? " < " : " <= "), mav->snapshot_sn) + ")";
-
-              r += (p ? ")" : "");
-            }
-            else
-              r = cmp (vm, (mao ? " < " : " <= "), mav->version);
-
-            return r;
-          };
-
-          auto min_cmp = [&vm, &sm, mio, &miv, &cmp] (bool p = false)
-          {
-            string r;
-
-            if (miv->snapshot ())
-            {
-              r += (p ? "(" : "");
-
-              r += cmp (vm, " > ", miv->version) + " || (";
-              r += cmp (vm, " == ", miv->version) + " && ";
-              r += cmp (sm, (mio ? " > " : " >= "), miv->snapshot_sn) + ")";
-
-              r += (p ? ")" : "");
-            }
-            else
-              r = cmp (vm, (mio ? " > " : " >= "), miv->version);
-
-            return r;
-          };
-
-          // < / <=
-          //
-          if (!miv)
-            return max_cmp ();
-
-          // > / >=
-          //
-          if (!mav)
-            return min_cmp ();
-
-          // ==
-          //
-          if (*miv == *mav)
-          {
-            string r (cmp (vm, " == ", miv->version));
-
-            if (miv->snapshot ())
-              r += " && " + cmp (sm, " == ", miv->snapshot_sn);
-
-            return r;
-          }
-
-          // range
-          //
-          return min_cmp (true) + " && " + max_cmp (true);
-        };
-
-        if (vn[1] == 'o') // condition
-          return cond ();
-
-        string r;
-
-        // This is tricky: if the version header hasn't been generated yet,
-        // then the check will fail. Maybe a better solution is to disable
-        // diagnostics and ignore (some) errors during dependency extraction.
-        //
-        r += "#ifdef " + vm + "\n";
-        r += "#  if !(" + cond () + ")\n";
-        r += "#    error incompatible " + dn->string () + " version, ";
-        r +=       dn->string () + ' ' + dc.string () + " is required\n";
-        r += "#  endif\n";
-        r += "#endif";
-
-        return r;
-      }
-      else
-        fail (l) << "unknown dependency substitution '" << vn << "'" << endf;
-    }
-
-    // manifest_install_rule
-    //
-    bool manifest_install_rule::
-    match (action a, target& t, const string&) const
-    {
-      // We only match project's manifest.
-      //
-      if (!t.is_a<manifest> () || t.name != "manifest")
-        return false;
-
-      // Must be in project's src_root.
-      //
-      const scope& s (t.base_scope ());
-      if (s.root_scope () != &s || s.src_path () != t.dir)
-        return false;
-
-      return file_rule::match (a, t, "");
-    }
-
-    auto_rmfile manifest_install_rule::
-    install_pre (const file& t, const install_dir&) const
-    {
-      const path& p (t.path ());
-
-      const scope& rs (t.root_scope ());
-      const module& m (*rs.lookup_module<module> (module::name));
-
-      if (!m.rewritten)
-        return auto_rmfile (p, false /* active */);
-
-      // Our options are to use path::temp_path() or to create a .t file in
-      // the out tree. Somehow the latter feels more appropriate (even though
-      // if we crash in between, we won't clean it up).
-      //
-      return fixup_manifest (p, rs.out_path () / "manifest.t", m.version);
-    }
-  }
-}
diff --git a/build2/version/rule.hxx b/build2/version/rule.hxx
deleted file mode 100644
index 7bfb783..0000000
--- a/build2/version/rule.hxx
+++ /dev/null
@@ -1,52 +0,0 @@
-// file      : build2/version/rule.hxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_VERSION_RULE_HXX
-#define BUILD2_VERSION_RULE_HXX
-
-#include <libbuild2/types.hxx>
-#include <libbuild2/utility.hxx>
-
-#include <libbuild2/install/rule.hxx>
-
-#include <libbuild2/in/rule.hxx>
-
-namespace build2
-{
-  namespace version
-  {
-    // Preprocess an .in file that depends on manifest.
-    //
-    class in_rule: public in::rule
-    {
-    public:
-      in_rule (): rule ("version.in 2", "version.in") {}
-
-      virtual bool
-      match (action, target&, const string&) const override;
-
-      virtual string
-      lookup (const location&,
-              action,
-              const target&,
-              const string&) const override;
-    };
-
-    // Pre-process manifest before installation to patch in the version.
-    //
-    class manifest_install_rule: public install::file_rule
-    {
-    public:
-      manifest_install_rule () {}
-
-      virtual bool
-      match (action, target&, const string&) const override;
-
-      virtual auto_rmfile
-      install_pre (const file&, const install_dir&) const override;
-    };
-  }
-}
-
-#endif // BUILD2_VERSION_RULE_HXX
diff --git a/build2/version/snapshot-git.cxx b/build2/version/snapshot-git.cxx
deleted file mode 100644
index f7993d2..0000000
--- a/build2/version/snapshot-git.cxx
+++ /dev/null
@@ -1,175 +0,0 @@
-// file      : build2/version/snapshot-git.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <ctime> // time_t
-
-#include <libbutl/sha1.mxx>
-
-#include <build2/version/snapshot.hxx>
-
-using namespace std;
-using namespace butl;
-
-namespace build2
-{
-  namespace version
-  {
-    snapshot
-    extract_snapshot_git (const dir_path& src_root)
-    {
-      snapshot r;
-      const char* d (src_root.string ().c_str ());
-
-      // First check whether the working directory is clean. There doesn't
-      // seem to be a way to do everything in a single invocation (the
-      // porcelain v2 gives us the commit id but not timestamp).
-      //
-
-      // If git status --porcelain returns anything, then the working
-      // directory is not clean.
-      //
-      {
-        const char* args[] {"git", "-C", d, "status", "--porcelain", nullptr};
-        r.committed = run<string> (
-          3 /* verbosity */,
-          args,
-          [](string& s, bool) {return move (s);}).empty ();
-      }
-
-      // Now extract the commit id and date. One might think that would be
-      // easy... Commit id is a SHA1 hash of the commit object. And commit
-      // object looks like this:
-      //
-      // commit <len>\0
-      // <data>
-      //
-      // Where <len> is the size of <data> and <data> is the output of:
-      //
-      // git cat-file commit HEAD
-      //
-      // There is also one annoying special case: new repository without any
-      // commits. In this case the above command will fail (with diagnostics
-      // and non-zero exit code) because there is no HEAD. Of course, it can
-      // also fail for other reason (like broken repository) which would be
-      // hard to distinguish. Note, however, that we just ran git status and
-      // it would have most likely failed if this were the case. So here we
-      // (reluctantly) assume that the only reason git cat-file fails is if
-      // there is no HEAD (that we equal with the "new repository" condition
-      // which is, strictly speaking, might not be the case either). So we
-      // suppress any diagnostics, and handle non-zero exit code.
-      //
-      string data;
-
-      const char* args[] {
-        "git", "-C", d, "cat-file", "commit", "HEAD", nullptr};
-      process pr (run_start (3     /* verbosity */,
-                             args,
-                             0     /* stdin  */,
-                             -1    /* stdout */,
-                             false /* error  */));
-
-      string l;
-      try
-      {
-        ifdstream is (move (pr.in_ofd), ifdstream::badbit);
-
-        while (!eof (getline (is, l)))
-        {
-          data += l;
-          data += '\n'; // We assume there is always a newline.
-
-          if (r.sn == 0 && l.compare (0, 10, "committer ") == 0)
-          try
-          {
-            // The line format is:
-            //
-            // committer <noise> <timestamp> <timezone>
-            //
-            // For example:
-            //
-            // committer John Doe <john@example.org> 1493117819 +0200
-            //
-            // The timestamp is in seconds since UNIX epoch. The timezone
-            // appears to be always numeric (+0000 for UTC). Note that
-            // timestamp appears to be already in UTC with timezone being just
-            // for information it seems.
-            //
-            size_t p1 (l.rfind (' ')); // Can't be npos.
-
-            size_t p2 (l.rfind (' ', p1 - 1));
-            if (p2 == string::npos)
-              throw invalid_argument ("missing timestamp");
-
-            string ts (l, p2 + 1, p1 - p2 - 1);
-            time_t t (static_cast<time_t> (stoull (ts)));
-
-#if 0
-            string tz (l, p1 + 1);
-
-            if (tz.size () != 5)
-              throw invalid_argument ("invalid timezone");
-
-            unsigned long h (stoul (string (tz, 1, 2)));
-            unsigned long m (stoul (string (tz, 3, 2)));
-            unsigned long s (h * 3600 + m * 60);
-
-            // The timezone indicates where the timestamp was generated so to
-            // convert to UTC we need to invert the sign.
-            //
-            switch (tz[0])
-            {
-            case '+': t -= s; break;
-            case '-': t += s; break;
-            default: throw invalid_argument ("invalid timezone sign");
-            }
-#endif
-            // Represent as YYYYMMDDhhmmss.
-            //
-            r.sn = stoull (to_string (system_clock::from_time_t (t),
-                                      "%Y%m%d%H%M%S",
-                                      false /* special */,
-                                      false /* local (already in UTC) */));
-          }
-          catch (const invalid_argument& e)
-          {
-            fail << "unable to extract git commit date from '" << l << "': "
-                 << e;
-          }
-        }
-
-        is.close ();
-      }
-      catch (const io_error&)
-      {
-        // Presumably the child process failed. Let run_finish() deal with
-        // that.
-      }
-
-      if (!run_finish (args, pr, false /* error */, l))
-      {
-        // Presumably new repository without HEAD. Return uncommitted snapshot
-        // with UNIX epoch as timestamp.
-        //
-        r.sn = 19700101000000ULL;
-        r.committed = false;
-        return r;
-      }
-
-      if (r.sn == 0)
-        fail << "unable to extract git commit id/date for " << src_root;
-
-      if (r.committed)
-      {
-        sha1 cs;
-        cs.append ("commit " + to_string (data.size ())); // Includes '\0'.
-        cs.append (data.c_str (), data.size ());
-        r.id.assign (cs.string (), 12); // 12-characters abbreviated commit id.
-      }
-      else
-        r.sn++; // Add a second.
-
-      return r;
-    }
-  }
-}
diff --git a/build2/version/snapshot.cxx b/build2/version/snapshot.cxx
deleted file mode 100644
index b43e083..0000000
--- a/build2/version/snapshot.cxx
+++ /dev/null
@@ -1,39 +0,0 @@
-// file      : build2/version/snapshot.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <build2/version/snapshot.hxx>
-
-#include <libbuild2/filesystem.hxx>
-
-using namespace std;
-
-namespace build2
-{
-  namespace version
-  {
-    snapshot
-    extract_snapshot_git (const dir_path&);
-
-    static const path git (".git");
-
-    snapshot
-    extract_snapshot (const scope& rs)
-    {
-      // Ignore errors when checking for existence since we may be iterating
-      // over directories past any reasonable project boundaries.
-      //
-      for (dir_path d (rs.src_path ()); !d.empty (); d = d.directory ())
-      {
-        // .git can be either a directory or a file in case of a submodule.
-        //
-        if (butl::entry_exists (d / git,
-                                true /* follow_symlinks */,
-                                true /* ignore_errors */))
-          return extract_snapshot_git (d);
-      }
-
-      return snapshot ();
-    }
-  }
-}
diff --git a/build2/version/snapshot.hxx b/build2/version/snapshot.hxx
deleted file mode 100644
index 824ec89..0000000
--- a/build2/version/snapshot.hxx
+++ /dev/null
@@ -1,34 +0,0 @@
-// file      : build2/version/snapshot.hxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_VERSION_SNAPSHOT_HXX
-#define BUILD2_VERSION_SNAPSHOT_HXX
-
-#include <libbuild2/types.hxx>
-#include <libbuild2/utility.hxx>
-
-#include <libbuild2/scope.hxx>
-
-namespace build2
-{
-  namespace version
-  {
-    struct snapshot
-    {
-      uint64_t sn = 0;
-      string id;
-      bool committed = false;
-
-      bool
-      empty () const {return sn == 0;}
-    };
-
-    // Return empty snapshot if unknown scm or uncommitted.
-    //
-    snapshot
-    extract_snapshot (const scope& rs);
-  }
-}
-
-#endif // BUILD2_VERSION_SNAPSHOT_HXX
diff --git a/build2/version/utility.cxx b/build2/version/utility.cxx
deleted file mode 100644
index 8286ff8..0000000
--- a/build2/version/utility.cxx
+++ /dev/null
@@ -1,81 +0,0 @@
-// file      : build2/version/utility.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <build2/version/utility.hxx>
-
-#include <libbutl/manifest-parser.mxx>
-#include <libbutl/manifest-serializer.mxx>
-
-#include <libbuild2/diagnostics.hxx>
-
-using namespace butl;
-
-namespace build2
-{
-  namespace version
-  {
-    auto_rmfile
-    fixup_manifest (const path& in, path out, const standard_version& v)
-    {
-      auto_rmfile r (move (out), !dry_run /* active */);
-
-      if (!dry_run)
-      {
-        try
-        {
-          permissions perm (path_permissions (in));
-
-          ifdstream ifs (in);
-          manifest_parser p (ifs, in.string ());
-
-          auto_fd ofd (fdopen (r.path,
-                               fdopen_mode::out       |
-                               fdopen_mode::create    |
-                               fdopen_mode::exclusive |
-                               fdopen_mode::binary,
-                               perm));
-
-          ofdstream ofs (move (ofd));
-          manifest_serializer s (ofs, r.path.string ());
-
-          manifest_name_value nv (p.next ());
-          assert (nv.name.empty () && nv.value == "1"); // We just loaded it.
-          s.next (nv.name, nv.value);
-
-          for (nv = p.next (); !nv.empty (); nv = p.next ())
-          {
-            if (nv.name == "version")
-              nv.value = v.string ();
-
-            s.next (nv.name, nv.value);
-          }
-
-          s.next (nv.name, nv.value); // End of manifest.
-          s.next (nv.name, nv.value); // End of stream.
-
-          ofs.close ();
-          ifs.close ();
-        }
-        catch (const manifest_parsing& e)
-        {
-          location l (&in, e.line, e.column);
-          fail (l) << e.description;
-        }
-        catch (const manifest_serialization& e)
-        {
-          location l (&r.path);
-          fail (l) << e.description;
-        }
-        catch (const io_error& e)
-        {
-          fail << "io error: " << e <<
-            info << "while reading " << in <<
-            info << "while writing " << r.path;
-        }
-      }
-
-      return r;
-    }
-  }
-}
diff --git a/build2/version/utility.hxx b/build2/version/utility.hxx
deleted file mode 100644
index 83bb91c..0000000
--- a/build2/version/utility.hxx
+++ /dev/null
@@ -1,25 +0,0 @@
-// file      : build2/version/utility.hxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_VERSION_UTILITY_HXX
-#define BUILD2_VERSION_UTILITY_HXX
-
-#include <libbuild2/types.hxx>
-#include <libbuild2/utility.hxx>
-
-#include <libbuild2/filesystem.hxx>
-
-namespace build2
-{
-  namespace version
-  {
-    // Re-serialize the manifest fixing up the version. Note that this will
-    // not preserve comments. Probably acceptable for snapshots.
-    //
-    auto_rmfile
-    fixup_manifest (const path& in, path out, const standard_version&);
-  }
-}
-
-#endif // BUILD2_VERSION_UTILITY_HXX