Save module map to pkg-config files

5 files changed, 91 insertions, 5 deletions

diff --git a/build2/cc/compile.cxx b/build2/cc/compile.cxx
index 6c3cc4c..9f36e8b 100644
--- a/build2/cc/compile.cxx
+++ b/build2/cc/compile.cxx
@@ -2766,8 +2766,8 @@ namespace build2
       // name for each mxx{} explicitly. This will be a major pain, however.
       // Another would be to require encoding of the module name in the
       // interface unit file name. For example, hello.core -> hello-core.mxx.
-      // This is better but will still too restrictive: some will want to call
-      // it hello_core.mxx or HelloCore.mxx (because that's their file naming
+      // This is better but still too restrictive: some will want to call it
+      // hello_core.mxx or HelloCore.mxx (because that's their file naming
       // convention) or place it in a subdirectory, say, hello/core.mxx.
       //
       // In the above examples one common theme about all the file names is
@@ -3010,6 +3010,8 @@ namespace build2
               // available.
               //
               // @@ MOD: BMI compatibility check.
+              // @@ UTL: we need to (recursively) see through libux{} (and
+              //    also in pkgconfig_save()).
               //
               if (bt != nullptr &&
                   (bt->is_a<bmis> () ||
diff --git a/build2/cc/pkgconfig.cxx b/build2/cc/pkgconfig.cxx
index 8d0ea25..d320060 100644
--- a/build2/cc/pkgconfig.cxx
+++ b/build2/cc/pkgconfig.cxx
@@ -733,6 +733,56 @@ namespace build2
 
         os << endl;
 
+        // If we have modules, list them in the modules variable. This code
+        // is pretty similar to compiler::search_modules().
+        //
+        if (modules)
+        {
+          os << endl
+             << "modules =";
+
+          for (const target* pt: l.prerequisite_targets)
+          {
+            // @@ UTL: we need to (recursively) see through libux{} (and
+            //    also in search_modules()).
+            //
+            if (pt != nullptr &&
+                (pt->is_a<bmis> () ||
+                 pt->is_a<bmia> () ||
+                 pt->is_a<bmie> ()))
+            {
+              // What we have is a binary module interface. What we need is
+              // a module interface source it was built from. We assume it's
+              // the first mxx{} target that we see.
+              //
+              const target* mt (nullptr);
+              for (const target* t: pt->prerequisite_targets)
+              {
+                if ((mt = t->is_a (*x_mod)))
+                  break;
+              }
+
+              // Can/should there be a bmi{} without mxx{}? Can't think of a
+              // reason.
+              //
+              assert (mt != nullptr);
+
+              path p (install::resolve_file (mt->as<file> ()));
+
+              if (p.empty ()) // Not installed.
+                continue;
+
+              const string& n (cast<string> (pt->vars[c_module_name]));
+
+              // Module name shouldn't require escaping.
+              //
+              os << ' ' << n << '=' << escape (p.string ());
+            }
+          }
+
+          os << endl;
+        }
+
         os.close ();
         arm.cancel ();
       }
diff --git a/build2/install/rule.cxx b/build2/install/rule.cxx
index c76800a..1f14fce 100644
--- a/build2/install/rule.cxx
+++ b/build2/install/rule.cxx
@@ -399,6 +399,29 @@ namespace build2
       return move (resolve (t, move (d)).back ().dir);
     }
 
+    path
+    resolve_file (const file& f)
+    {
+      // Note: similar logic to perform_install().
+      //
+      const path* p (lookup_install<path> (f, "install"));
+
+      if (p == nullptr) // Not installable.
+        return path ();
+
+      bool n (!p->to_directory ());
+      dir_path d (n ? p->directory () : path_cast<dir_path> (*p));
+
+      install_dirs ids (resolve (f, d));
+      if (auto l = f["install.subdirs"])
+      {
+        if (cast<bool> (l))
+          resolve_subdir (ids, f, f.base_scope (), l);
+      }
+
+      return ids.back ().dir / (n ? p->leaf () : f.path ().leaf ());
+    }
+
     // On Windows we use MSYS2 install.exe and MSYS2 by default ignores
     // filesystem permissions (noacl mount option). And this means, for
     // example, that .exe that we install won't be runnable by Windows (MSYS2
@@ -631,6 +654,8 @@ namespace build2
 
       auto install_target = [this] (const file& t, const path& p, bool verbose)
       {
+        // Note: similar logic to resolve_file().
+        //
         bool n (!p.to_directory ());
         dir_path d (n ? p.directory () : path_cast<dir_path> (p));
 
diff --git a/build2/install/utility.hxx b/build2/install/utility.hxx
index 21c0c44..173b25c 100644
--- a/build2/install/utility.hxx
+++ b/build2/install/utility.hxx
@@ -9,6 +9,7 @@
 #include <build2/utility.hxx>
 
 #include <build2/scope.hxx>
+#include <build2/target.hxx>
 
 namespace build2
 {
@@ -57,6 +58,11 @@ namespace build2
     //
     dir_path
     resolve_dir (const target&, dir_path); // rule.cxx
+
+    // Resolve file installation path returning empty path if not installable.
+    //
+    path
+    resolve_file (const file&); // rule.cxx
   }
 }
 
diff --git a/build2/target.hxx b/build2/target.hxx
index 3af533f..94fb800 100644
--- a/build2/target.hxx
+++ b/build2/target.hxx
@@ -640,8 +640,9 @@ namespace build2
     // Target type info and casting.
     //
   public:
-    bool
-    is_a (const target_type& tt) const {return type ().is_a (tt);}
+    const target*
+    is_a (const target_type& tt) const {
+      return type ().is_a (tt) ? this : nullptr;}
 
     template <typename T>
     T*
@@ -871,7 +872,9 @@ namespace build2
     bool
     is_a (const target_type_type& tt) const
     {
-      return target != nullptr ? target->is_a (tt) : prerequisite.is_a (tt);
+      return target != nullptr
+        ? target->is_a (tt) != nullptr
+        : prerequisite.is_a (tt);
     }
 
     prerequisite_key