Essential install module functionality

1 files changed, 365 insertions, 0 deletions

diff --git a/build/install/rule.cxx b/build/install/rule.cxx
new file mode 100644
index 0000000..5642388
--- /dev/null
+++ b/build/install/rule.cxx
@@ -0,0 +1,365 @@
+// file      : build/install/rule.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build/install/rule>
+
+#include <butl/process>
+#include <butl/filesystem>
+
+#include <build/scope>
+#include <build/target>
+#include <build/algorithm>
+#include <build/diagnostics>
+
+#include <build/config/utility>
+
+using namespace std;
+using namespace butl;
+
+namespace build
+{
+  namespace install
+  {
+    // Lookup the install or install.* variable and check that
+    // the value makes sense. Return NULL if not found or if
+    // the value is the special 'false' name (which means do
+    // not install). T is either scope or target.
+    //
+    template <typename T>
+    static const name*
+    lookup (T& t, const char* var)
+    {
+      auto v (t[var]);
+
+      const name* r (nullptr);
+
+      if (!v)
+        return r;
+
+      const list_value& lv (v.template as<const list_value&> ());
+
+      if (lv.empty ())
+        return r;
+
+      if (lv.size () == 1)
+      {
+        const name& n (lv.front ());
+
+        if (n.simple () && n.value == "false")
+          return r;
+
+        if (!n.empty () && (n.simple () || n.directory ()))
+          return &n;
+      }
+
+      fail << "expected directory instead of '" << lv << "' in "
+           << "the " << var << " variable";
+
+      return r;
+    }
+
+    template <typename T>
+    static inline const name*
+    lookup (T& t, const string& var) {return lookup (t, var.c_str ());}
+
+    match_result rule::
+    match (action a, target& t, const std::string&) const
+    {
+      // First determine if this target should be installed (called
+      // "installable" for short).
+      //
+      match_result mr (t, lookup (t, "install") != nullptr);
+
+      // If this is the update pre-operation, change the recipe action
+      // to (update, 0) (i.e., "unconditional update").
+      //
+      if (mr.bvalue && a.operation () == update_id)
+        mr.recipe_action = action (a.meta_operation (), update_id);
+
+      return mr;
+    }
+
+    recipe rule::
+    apply (action a, target& t, const match_result& mr) const
+    {
+      if (!mr.bvalue) // Not installable.
+        return noop_recipe;
+
+      // In case of install, we don't do anything for other meta-operations.
+      //
+      if (a.operation () == install_id && a.meta_operation () != perform_id)
+        return noop_recipe;
+
+      // Ok, if we are here, then this means:
+      //
+      // 1. This target is installable.
+      // 2. The action is either
+      //    a. (perform, install, 0) or
+      //    b. (*, update, install)
+      //
+      // In both cases, the next step is to search, match, and collect
+      // all the installable prerequisites.
+      //
+      // @@ Perhaps if [noinstall] will be handled by the
+      // group_prerequisite_members machinery, then we can just
+      // run standard search_and_match()? Will need an indicator
+      // that it was forced (e.g., [install]) for filter() below.
+      //
+      for (prerequisite_member p: group_prerequisite_members (a, t))
+      {
+        // @@ This is where we will handle [noinstall].
+        //
+
+        // Let a customized rule have its say.
+        //
+        // @@ This will be skipped if forced with [install].
+        //
+        if (!filter (a, t, p))
+          continue;
+
+        target& pt (p.search ());
+        build::match (a, pt);
+
+        // If the matched rule returned noop_recipe, then the target
+        // state will be set to unchanged as an optimization. Use this
+        // knowledge to optimize things on our side as well since this
+        // will help a lot in case of any static installable content
+        // (headers, documentation, etc).
+        //
+        // @@ This messes up the dependents count logic.
+        //
+        if (pt.state () != target_state::unchanged)
+          t.prerequisite_targets.push_back (&pt);
+      }
+
+      // This is where we diverge depending on the operation. In the
+      // update pre-operation, we need to make sure that this target
+      // as well as all its installable prerequisites are up to date.
+      //
+      if (a.operation () == update_id)
+      {
+        // Save the prerequisite targets that we found since the
+        // call to match_delegate() below will wipe them out.
+        //
+        target::prerequisite_targets_type p;
+
+        if (!t.prerequisite_targets.empty ())
+          p.swap (t.prerequisite_targets);
+
+        // Find the "real" update rule, that is, the rule that would
+        // have been found if we signalled that we do not match from
+        // match() above.
+        //
+        recipe d (match_delegate (a, t).first);
+
+        // If we have no installable prerequsites, then simply redirect
+        // to it.
+        //
+        if (p.empty ())
+          return d;
+
+        // Ok, the worst case scenario: we need to cause update of
+        // prerequisite targets and also delegate to the real update.
+        //
+        return [pt = move (p), dr = move (d)]
+          (action a, target& t) mutable -> target_state
+        {
+          // Do the target update first.
+          //
+          target_state r (execute_delegate (dr, a, t));
+
+          // Swap our prerequisite targets back in and execute.
+          //
+          t.prerequisite_targets.swap (pt);
+          r |= execute_prerequisites (a, t);
+          pt.swap (t.prerequisite_targets); // In case we get re-executed.
+
+          return r;
+        };
+      }
+      else
+        return &perform_install;
+    }
+
+    struct install_dir
+    {
+      dir_path dir;
+      string cmd;
+      const list_value* options {nullptr};
+      string mode;
+      string dir_mode;
+    };
+
+    // install -d <dir>
+    //
+    static void
+    install (const install_dir& base, const dir_path& d)
+    {
+      path reld (relative (d));
+
+      cstrings args {base.cmd.c_str (), "-d"};
+
+      if (base.options != nullptr)
+        config::append_options (args, *base.options, "install.*.options");
+
+      args.push_back ("-m");
+      args.push_back (base.dir_mode.c_str ());
+      args.push_back (reld.string ().c_str ());
+      args.push_back (nullptr);
+
+      if (verb)
+        print_process (args);
+      else
+        text << "install " << d;
+
+      try
+      {
+        process pr (args.data ());
+
+        if (!pr.wait ())
+          throw failed ();
+      }
+      catch (const process_error& e)
+      {
+        error << "unable to execute " << args[0] << ": " << e.what ();
+
+        if (e.child ())
+          exit (1);
+
+        throw failed ();
+      }
+    }
+
+    // install <file> <dir>
+    //
+    static void
+    install (const install_dir& base, file& t)
+    {
+      path reld (relative (base.dir));
+      path relf (relative (t.path ()));
+
+      cstrings args {base.cmd.c_str ()};
+
+      if (base.options != nullptr)
+        config::append_options (args, *base.options, "install.*.options");
+
+      args.push_back ("-m");
+      args.push_back (base.mode.c_str ());
+      args.push_back (relf.string ().c_str ());
+      args.push_back (reld.string ().c_str ());
+      args.push_back (nullptr);
+
+      if (verb)
+        print_process (args);
+      else
+        text << "install " << t;
+
+      try
+      {
+        process pr (args.data ());
+
+        if (!pr.wait ())
+          throw failed ();
+      }
+      catch (const process_error& e)
+      {
+        error << "unable to execute " << args[0] << ": " << e.what ();
+
+        if (e.child ())
+          exit (1);
+
+        throw failed ();
+      }
+    }
+
+    // Resolve installation directory name to absolute directory path,
+    // creating leading directories as necessary.
+    //
+    static install_dir
+    resolve (scope& s, const name& n, const string* var = nullptr)
+    {
+      install_dir r;
+      dir_path d (n.simple () ? dir_path (n.value) : n.dir);
+
+      if (d.absolute ())
+      {
+        d.normalize ();
+
+        // Make sure it already exists (this will normally be
+        // install.root with everything else defined in term of it).
+        //
+        if (!dir_exists (d))
+          fail << "installation directory " << d << " does not exist";
+      }
+      else
+      {
+        // If it is relative, then the first component is treated
+        // as the installation directory name, e.g., bin, sbin, lib,
+        // etc. Look it up and recurse.
+        //
+        const string& dn (*d.begin ());
+        const string var ("install." + dn);
+        if (const name* n = lookup (s, var))
+        {
+          r = resolve (s, *n, &var);
+          d = r.dir / dir_path (++d.begin (), d.end ());
+          d.normalize ();
+
+          if (!dir_exists (d))
+            install (r, d); // install -d
+        }
+        else
+          fail << "unknown installation directory name " << dn <<
+            info << "did you forget to specify config." << var << "?";
+      }
+
+      r.dir = move (d);
+
+      // Override components in install_dir if we have our own.
+      //
+      if (var != nullptr)
+      {
+        if (auto v = s[*var + ".cmd"]) r.cmd = v.as<const string&> ();
+        if (auto v = s[*var + ".mode"]) r.mode = v.as<const string&> ();
+        if (auto v = s[*var + ".dir_mode"])
+          r.dir_mode = v.as<const string&> ();
+        if (auto v = s[*var + ".options"])
+          r.options = &v.as<const list_value&> ();
+      }
+
+      // Set defaults for unspecified components.
+      //
+      if (r.cmd.empty ()) r.cmd = "install";
+      if (r.mode.empty ()) r.mode = "644";
+      if (r.dir_mode.empty ()) r.dir_mode = "755";
+
+      return r;
+    }
+
+    target_state rule::
+    perform_install (action a, target& t)
+    {
+      file& ft (static_cast<file&> (t));
+      assert (!ft.path ().empty ()); // Should have been assigned by update.
+
+      // First handle installable prerequisites.
+      //
+      target_state r (execute_prerequisites (a, t));
+
+      // Resolve and, if necessary, create target directory.
+      //
+      install_dir d (
+        resolve (t.base_scope (),
+                 t["install"].as<const name&> ())); // We know it's there.
+
+      // Override mode if one was specified.
+      //
+      if (auto v = t["install.mode"])
+        d.mode = v.as<const string&> ();
+
+      install (d, ft);
+      return (r |= target_state::changed);
+    }
+  }
+}