Add metadata for exe{b}, including whether it is statically-linked

Use this information to omit ad hoc C++ recipe tests is testing statically-
linked build system.

10 files changed, 100 insertions, 15 deletions

diff --git a/build2/b-options.cxx b/build2/b-options.cxx
index 4dadf99..ce322cc 100644
--- a/build2/b-options.cxx
+++ b/build2/b-options.cxx
@@ -674,7 +674,9 @@ namespace build2
 
   options::
   options ()
-  : v_ (),
+  : build2_metadata_ (),
+    build2_metadata_specified_ (false),
+    v_ (),
     V_ (),
     quiet_ (),
     silent_ (),
@@ -787,6 +789,13 @@ namespace build2
   {
     CLI_POTENTIALLY_UNUSED (a);
 
+    if (a.build2_metadata_specified_)
+    {
+      ::build2::cl::parser< uint64_t>::merge (
+        this->build2_metadata_, a.build2_metadata_);
+      this->build2_metadata_specified_ = true;
+    }
+
     if (a.v_)
     {
       ::build2::cl::parser< bool>::merge (
@@ -1202,6 +1211,9 @@ namespace build2
   {
     _cli_options_map_init ()
     {
+      _cli_options_map_["--build2-metadata"] =
+      &::build2::cl::thunk< options, uint64_t, &options::build2_metadata_,
+        &options::build2_metadata_specified_ >;
       _cli_options_map_["-v"] =
       &::build2::cl::thunk< options, bool, &options::v_ >;
       _cli_options_map_["-V"] =
diff --git a/build2/b-options.hxx b/build2/b-options.hxx
index 44777f7..c6f1f59 100644
--- a/build2/b-options.hxx
+++ b/build2/b-options.hxx
@@ -453,6 +453,12 @@ namespace build2
 
     // Option accessors.
     //
+    const uint64_t&
+    build2_metadata () const;
+
+    bool
+    build2_metadata_specified () const;
+
     const bool&
     v () const;
 
@@ -598,6 +604,8 @@ namespace build2
             ::build2::cl::unknown_mode argument);
 
     public:
+    uint64_t build2_metadata_;
+    bool build2_metadata_specified_;
     bool v_;
     bool V_;
     bool quiet_;
diff --git a/build2/b-options.ixx b/build2/b-options.ixx
index b8d7198..6444aa9 100644
--- a/build2/b-options.ixx
+++ b/build2/b-options.ixx
@@ -260,6 +260,18 @@ namespace build2
   // options
   //
 
+  inline const uint64_t& options::
+  build2_metadata () const
+  {
+    return this->build2_metadata_;
+  }
+
+  inline bool options::
+  build2_metadata_specified () const
+  {
+    return this->build2_metadata_specified_;
+  }
+
   inline const bool& options::
   v () const
   {
diff --git a/build2/b.cli b/build2/b.cli
index 355e2d9..f65d14a 100644
--- a/build2/b.cli
+++ b/build2/b.cli
@@ -389,6 +389,8 @@ namespace build2
   {
     "\h#options|OPTIONS|"
 
+    uint64_t --build2-metadata; // Leave undocumented/hidden.
+
     bool -v
     {
       "Print actual commands being executed. This options is equivalent to
diff --git a/build2/b.cxx b/build2/b.cxx
index bae40b6..930dbac 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -426,32 +426,61 @@ main (int argc, char* argv[])
       fail << e;
     }
 
-    // Initialize the diagnostics state.
+    // Handle --build2-metadata (see also buildfile).
     //
-    init_diag (verbosity (),
-               ops.silent (),
-               (ops.progress ()    ? optional<bool> (true)  :
-                ops.no_progress () ? optional<bool> (false) : nullopt),
-               ops.no_line (),
-               ops.no_column (),
-               fdterm (stderr_fd ()));
+#ifndef BUILD2_BOOTSTRAP
+    if (ops.build2_metadata_specified ())
+    {
+      auto& o (cout);
+
+      // Note that the export.metadata variable should be the first non-
+      // blank/comment line.
+      //
+      o << "# build2 buildfile b" << endl
+        << "export.metadata = 1 b" << endl
+        << "b.name = [string] b" << endl
+        << "b.version = [string] '" << LIBBUILD2_VERSION_FULL << '\'' << endl
+        << "b.checksum = [string] '" << LIBBUILD2_VERSION_FULL << '\'' << endl
+        << "b.static = [bool] " <<
+#ifdef LIBBUILD2_STATIC
+        "true"
+#else
+        "false"
+#endif
+        << endl;
+
+      return 0;
+    }
+#endif
 
     // Handle --version.
     //
     if (ops.version ())
     {
-      cout << "build2 " << LIBBUILD2_VERSION_ID << endl
-           << "libbutl " << LIBBUTL_VERSION_ID << endl
-           << "host " << BUILD2_HOST_TRIPLET << endl;
+      auto& o (cout);
+
+      o << "build2 " << LIBBUILD2_VERSION_ID << endl
+        << "libbutl " << LIBBUTL_VERSION_ID << endl
+        << "host " << BUILD2_HOST_TRIPLET << endl;
 
 #ifndef BUILD2_BOOTSTRAP
-      cout << "Copyright (c) " << BUILD2_COPYRIGHT << "." << endl;
+      o << "Copyright (c) " << BUILD2_COPYRIGHT << "." << endl;
 #endif
 
-      cout << "This is free software released under the MIT license." << endl;
+      o << "This is free software released under the MIT license." << endl;
       return 0;
     }
 
+    // Initialize the diagnostics state.
+    //
+    init_diag (verbosity (),
+               ops.silent (),
+               (ops.progress ()    ? optional<bool> (true)  :
+                ops.no_progress () ? optional<bool> (false) : nullopt),
+               ops.no_line (),
+               ops.no_column (),
+               fdterm (stderr_fd ()));
+
     // Handle --help.
     //
     if (ops.help ())
diff --git a/build2/buildfile b/build2/buildfile
index 3be724c..4d62fb5 100644
--- a/build2/buildfile
+++ b/build2/buildfile
@@ -16,6 +16,17 @@ for m: bash bin c cc cxx in version
 
 exe{b}: {hxx ixx txx cxx}{** -b-options} {hxx ixx cxx}{b-options} $libs
 
+# Target metadata, see also --build2-metadata in b.cxx.
+#
+exe{b}:
+{
+  export.metadata = 1 b
+  b.name = [string] b
+  b.version  = $version
+  b.checksum = $version
+  b.static = ($bin.link_member(exe) == liba)
+}
+
 # Build options.
 #
 # Pass our compiler target to be used as build2 host.
diff --git a/libbuild2/version.hxx.in b/libbuild2/version.hxx.in
index d221d03..a9db847 100644
--- a/libbuild2/version.hxx.in
+++ b/libbuild2/version.hxx.in
@@ -28,6 +28,7 @@
 #define LIBBUILD2_VERSION       $build2.version.project_number$ULL
 #define LIBBUILD2_VERSION_STR   "$build2.version.project$"
 #define LIBBUILD2_VERSION_ID    "$build2.version.project_id$"
+#define LIBBUILD2_VERSION_FULL  "$build2.version$"
 
 #define LIBBUILD2_VERSION_MAJOR $build2.version.major$
 #define LIBBUILD2_VERSION_MINOR $build2.version.minor$
diff --git a/tests/build/root.build b/tests/build/root.build
index 4ac2957..e3f0f61 100644
--- a/tests/build/root.build
+++ b/tests/build/root.build
@@ -19,8 +19,11 @@ if ($cxx.class == 'msvc')
 # path.
 #
 import.build2 = [null]
+import! [metadata] b = build2%exe{b}
+
+static = $($b:b.static) # True if testing statically-linked build system.
+shared = (!$static)     # For '$shared || exit' idiom.
 
-import b = build2%exe{b}
 testscript{*}: test = $b
 
 # Specify the test target for cross-testing.
diff --git a/tests/dependency/recipe/testscript b/tests/dependency/recipe/testscript
index 5f9bdf1..bd33bcc 100644
--- a/tests/dependency/recipe/testscript
+++ b/tests/dependency/recipe/testscript
@@ -708,6 +708,8 @@ EOE
     :
     : Disable when cross-testing for the sake of simplicity.
     :
+    #\
+    # @@ There is now metadata and name in exe{b}.
     if ($test.target == $build.host)
     {
       $* <<EOI 2>>/~%EOE% != 0
@@ -724,6 +726,7 @@ EOE
           info: or provide custom low-verbosity diagnostics with the 'diag' builtin
         EOE
     }
+    #\
 
     : program
     :
diff --git a/tests/recipe/cxx/testscript b/tests/recipe/cxx/testscript
index 3eb8015..6601c0a 100644
--- a/tests/recipe/cxx/testscript
+++ b/tests/recipe/cxx/testscript
@@ -1,6 +1,10 @@
 # file      : tests/recipe/cxx/testscript
 # license   : MIT; see accompanying LICENSE file
 
+# Ad hoc C++ recipes not supported in a statically-linked build system.
+#
++$shared || exit
+
 +mkdir build
 +cat <<EOI >=build/bootstrap.build
   project = test