Move version build system module to separate library

1 files changed, 407 insertions, 0 deletions

diff --git a/libbuild2/version/init.cxx b/libbuild2/version/init.cxx
new file mode 100644
index 0000000..8adbb29
--- /dev/null
+++ b/libbuild2/version/init.cxx
@@ -0,0 +1,407 @@
+// file      : libbuild2/version/init.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <libbuild2/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 <libbuild2/version/rule.hxx>
+#include <libbuild2/version/module.hxx>
+#include <libbuild2/version/utility.hxx>
+#include <libbuild2/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.* variables, 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;
+      }
+    }
+
+    static const module_functions mod_functions[] =
+    {
+      // NOTE: don't forget to also update the documentation in init.hxx if
+      //       changing anything here.
+
+      {"version", boot,    init},
+      {nullptr,   nullptr, nullptr}
+    };
+
+    const module_functions*
+    build2_version_load ()
+    {
+      return mod_functions;
+    }
+  }
+}