Move c build system module to separate library

7 files changed, 559 insertions, 1 deletions

diff --git a/libbuild2/buildfile b/libbuild2/buildfile
index aad4e78..75731fc 100644
--- a/libbuild2/buildfile
+++ b/libbuild2/buildfile
@@ -5,7 +5,7 @@
 # NOTE: remember to update bundled_modules in libbuild2/modules.cxx if adding
 #       a new module.
 #
-./: lib{build2} bash/ bin/ cc/ in/ version/
+./: lib{build2} bash/ bin/ c/ cc/ in/ version/
 
 import int_libs = libbutl%lib{butl}
 
diff --git a/libbuild2/c/buildfile b/libbuild2/c/buildfile
new file mode 100644
index 0000000..39a5d7a
--- /dev/null
+++ b/libbuild2/c/buildfile
@@ -0,0 +1,90 @@
+# file      : libbuild2/c/buildfile
+# copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+# license   : MIT; see accompanying LICENSE file
+
+import int_libs = libbutl%lib{butl}
+
+include ../
+int_libs += ../lib{build2}
+
+include ../cc/
+int_libs += ../cc/lib{build2-cc}
+
+./: lib{build2-c}: libul{build2-c}: {hxx ixx txx cxx}{** -**.test...} \
+  $int_libs
+
+# Unit tests.
+#
+exe{*.test}:
+{
+  test = true
+  install = false
+}
+
+for t: cxx{**.test...}
+{
+  d = $directory($t)
+  n = $name($t)...
+
+  ./: $d/exe{$n}: $t $d/{hxx ixx txx}{+$n} $d/testscript{+$n}
+  $d/exe{$n}: libul{build2-c}: bin.whole = false
+}
+
+# Build options.
+#
+obja{*}: cxx.poptions += -DLIBBUILD2_C_STATIC_BUILD
+objs{*}: cxx.poptions += -DLIBBUILD2_C_SHARED_BUILD
+
+# Note that we used to compare complete target triplets but that proved too
+# strict (see libbuild2/buildfile for details).
+#
+cross = ($cxx.target.cpu != $build.host.cpu || \
+         $cxx.target.system != $build.host.system)
+
+# Pass native C compiler path (not forgetting to escape backslashes on
+# Windows). It is used as defaults for BUILD2_DEFAULT_C.
+#
+if! $cross
+{
+  obj{init}: cxx.poptions += \
+    -DBUILD2_NATIVE_C=\"$regex.replace($recall($c.path), '\\', '\\\\')\"
+
+  obja{init}: cxx.poptions += -DLIBBUILD2_C_STATIC_BUILD
+  objs{init}: cxx.poptions += -DLIBBUILD2_C_SHARED_BUILD
+}
+
+# Export options.
+#
+lib{build2-c}:
+{
+  cxx.export.poptions = "-I$out_root" "-I$src_root"
+  cxx.export.libs = $int_libs
+}
+
+liba{build2-c}: cxx.export.poptions += -DLIBBUILD2_C_STATIC
+libs{build2-c}: cxx.export.poptions += -DLIBBUILD2_C_SHARED
+
+# For pre-releases use the complete version to make sure they cannot be used
+# in place of another pre-release or the final version. See the version module
+# for details on the version.* variable values.
+#
+# And because this is a build system module, we also embed the same value as
+# the interface version (note that we cannot use build.version.interface for
+# bundled modules because we could be built with a different version of the
+# build system).
+#
+ver = ($version.pre_release    \
+       ? "$version.project_id" \
+       : "$version.major.$version.minor")
+
+lib{build2-c}: bin.lib.version = @"-$ver"
+libs{build2-c}: bin.lib.load_suffix = "-$ver"
+
+# Install into the libbuild2/c/ subdirectory of, say, /usr/include/
+# recreating subdirectories.
+#
+{hxx ixx txx}{*}:
+{
+  install         = include/libbuild2/c/
+  install.subdirs = true
+}
diff --git a/libbuild2/c/export.hxx b/libbuild2/c/export.hxx
new file mode 100644
index 0000000..6fe3203
--- /dev/null
+++ b/libbuild2/c/export.hxx
@@ -0,0 +1,38 @@
+// file      : libbuild2/c/export.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#pragma once
+
+// Normally we don't export class templates (but do complete specializations),
+// inline functions, and classes with only inline member functions. Exporting
+// classes that inherit from non-exported/imported bases (e.g., std::string)
+// will end up badly. The only known workarounds are to not inherit or to not
+// export. Also, MinGW GCC doesn't like seeing non-exported functions being
+// used before their inline definition. The workaround is to reorder code. In
+// the end it's all trial and error.
+
+#if defined(LIBBUILD2_C_STATIC)         // Using static.
+#  define LIBBUILD2_C_SYMEXPORT
+#elif defined(LIBBUILD2_C_STATIC_BUILD) // Building static.
+#  define LIBBUILD2_C_SYMEXPORT
+#elif defined(LIBBUILD2_C_SHARED)       // Using shared.
+#  ifdef _WIN32
+#    define LIBBUILD2_C_SYMEXPORT __declspec(dllimport)
+#  else
+#    define LIBBUILD2_C_SYMEXPORT
+#  endif
+#elif defined(LIBBUILD2_C_SHARED_BUILD) // Building shared.
+#  ifdef _WIN32
+#    define LIBBUILD2_C_SYMEXPORT __declspec(dllexport)
+#  else
+#    define LIBBUILD2_C_SYMEXPORT
+#  endif
+#else
+// If none of the above macros are defined, then we assume we are being used
+// by some third-party build system that cannot/doesn't signal the library
+// type. Note that this fallback works for both static and shared but in case
+// of shared will be sub-optimal compared to having dllimport.
+//
+#  define LIBBUILD2_C_SYMEXPORT         // Using static or shared.
+#endif
diff --git a/libbuild2/c/init.cxx b/libbuild2/c/init.cxx
new file mode 100644
index 0000000..43d647f
--- /dev/null
+++ b/libbuild2/c/init.cxx
@@ -0,0 +1,375 @@
+// file      : libbuild2/c/init.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <libbuild2/c/init.hxx>
+
+#include <libbuild2/scope.hxx>
+#include <libbuild2/diagnostics.hxx>
+
+#include <libbuild2/cc/guess.hxx>
+#include <libbuild2/cc/module.hxx>
+
+#include <libbuild2/c/target.hxx>
+
+#ifndef BUILD2_DEFAULT_C
+#  ifdef BUILD2_NATIVE_C
+#    define BUILD2_DEFAULT_C BUILD2_NATIVE_C
+#  else
+#    define BUILD2_DEFAULT_C ""
+#  endif
+#endif
+
+using namespace std;
+using namespace butl;
+
+namespace build2
+{
+  namespace c
+  {
+    using cc::compiler_id;
+    using cc::compiler_class;
+    using cc::compiler_info;
+
+    class config_module: public cc::config_module
+    {
+    public:
+      explicit
+      config_module (config_data&& d)
+          : config_data (move (d)), cc::config_module (move (d)) {}
+
+      virtual strings
+      translate_std (const compiler_info&,
+                     scope&,
+                     const string*) const override;
+    };
+
+    using cc::module;
+
+    strings config_module::
+    translate_std (const compiler_info& ci, scope& rs, const string* v) const
+    {
+      strings r;
+
+      switch (ci.class_)
+      {
+      case compiler_class::msvc:
+        {
+          // Standard-wise, with VC you get what you get. The question is
+          // whether we should verify that the requested standard is provided
+          // by this VC version. And if so, from which version should we say
+          // VC supports 90, 99, and 11? We should probably be as loose as
+          // possible here since the author will always be able to tighten
+          // (but not loosen) this in the buildfile (i.e., detect unsupported
+          // versions).
+          //
+          // The state of affairs seem to be (from Herb Sutter's blog):
+          //
+          // 10.0 - most of C95 plus a few C99 features
+          // 11.0 - partial support for the C++11 subset of C11
+          // 12.0 - more C11 features from the C++11 subset, most of C99
+          //
+          // So let's say C99 is supported from 10.0 and C11 from 11.0. And
+          // C90 is supported by everything we care to support.
+          //
+          // C17 is a bug-fix version of C11 so here we assume it is the same
+          // as C11.
+          //
+          if (v == nullptr)
+            ;
+          else if (*v != "90")
+          {
+            uint64_t cver (ci.version.major);
+
+            if ((*v == "99"   && cver < 16) || // Since VS2010/10.0.
+                ((*v == "11" ||
+                  *v == "17") && cver < 17))   // Since VS2012/11.0.
+            {
+              fail << "C" << *v << " is not supported by " << ci.signature <<
+                info << "required by " << project (rs) << '@' << rs;
+            }
+          }
+          break;
+        }
+      case compiler_class::gcc:
+        {
+          // 90 and 89 are the same standard. Translate 99 to 9x and 11 to 1x
+          // for compatibility with older versions of the compilers.
+          //
+          if (v == nullptr)
+            ;
+          else
+          {
+            string o ("-std=");
+
+            if      (*v == "90") o += "c90";
+            else if (*v == "99") o += "c9x";
+            else if (*v == "11") o += "c1x";
+            else if (*v == "17") o += "c17"; // GCC 8, Clang 6.
+            else o += *v; // In case the user specifies e.g., 'gnu11'.
+
+            r.push_back (move (o));
+          }
+          break;
+        }
+      }
+
+      return r;
+    }
+
+    static const char* const hinters[] = {"cxx", nullptr};
+
+    // See cc::module for details on guess_init vs config_init.
+    //
+    bool
+    guess_init (scope& rs,
+                scope& bs,
+                const location& loc,
+                unique_ptr<module_base>& mod,
+                bool,
+                bool,
+                const variable_map& hints)
+    {
+      tracer trace ("c::guess_init");
+      l5 ([&]{trace << "for " << bs;});
+
+      // We only support root loading (which means there can only be one).
+      //
+      if (&rs != &bs)
+        fail (loc) << "c.guess module must be loaded in project root";
+
+      // Load cc.core.vars so that we can cache all the cc.* variables.
+      //
+      if (!cast_false<bool> (rs["cc.core.vars.loaded"]))
+        load_module (rs, rs, "cc.core.vars", loc);
+
+      // Enter all the variables and initialize the module data.
+      //
+      auto& v (rs.ctx.var_pool.rw (rs));
+
+      cc::config_data d {
+        cc::lang::c,
+
+        "c",
+        "c",
+        BUILD2_DEFAULT_C,
+        ".i",
+
+        hinters,
+
+        // Note: some overridable, some not.
+        //
+        v.insert<path>    ("config.c",          true),
+        v.insert<string>  ("config.c.id",       true),
+        v.insert<string>  ("config.c.version",  true),
+        v.insert<string>  ("config.c.target",   true),
+        v.insert<string>  ("config.c.std",      true),
+        v.insert<strings> ("config.c.poptions", true),
+        v.insert<strings> ("config.c.coptions", true),
+        v.insert<strings> ("config.c.loptions", true),
+        v.insert<strings> ("config.c.aoptions", true),
+        v.insert<strings> ("config.c.libs",     true),
+        nullptr          /* config.c.importable_headers */,
+
+        v.insert<process_path> ("c.path"),
+        v.insert<dir_paths>    ("c.sys_lib_dirs"),
+        v.insert<dir_paths>    ("c.sys_inc_dirs"),
+
+        v.insert<string>       ("c.std", variable_visibility::project),
+
+        v.insert<strings>      ("c.poptions"),
+        v.insert<strings>      ("c.coptions"),
+        v.insert<strings>      ("c.loptions"),
+        v.insert<strings>      ("c.aoptions"),
+        v.insert<strings>      ("c.libs"),
+
+        nullptr                /* c.importable_headers */,
+
+        v["cc.poptions"],
+        v["cc.coptions"],
+        v["cc.loptions"],
+        v["cc.aoptions"],
+        v["cc.libs"],
+
+        v.insert<strings>      ("c.export.poptions"),
+        v.insert<strings>      ("c.export.coptions"),
+        v.insert<strings>      ("c.export.loptions"),
+        v.insert<vector<name>> ("c.export.libs"),
+
+        v["cc.export.poptions"],
+        v["cc.export.coptions"],
+        v["cc.export.loptions"],
+        v["cc.export.libs"],
+
+        v.insert_alias (v["cc.stdlib"], "c.stdlib"), // Same as cc.stdlib.
+
+        v["cc.runtime"],
+        v["cc.stdlib"],
+
+        v["cc.type"],
+        v["cc.system"],
+        v["cc.module_name"],
+        v["cc.reprocess"],
+
+        v.insert<string>   ("c.preprocessed"), // See cxx.preprocessed.
+        nullptr,                               // No __symexport (no modules).
+
+        v.insert<string>   ("c.id"),
+        v.insert<string>   ("c.id.type"),
+        v.insert<string>   ("c.id.variant"),
+
+        v.insert<string>   ("c.class"),
+
+        v.insert<string>   ("c.version"),
+        v.insert<uint64_t> ("c.version.major"),
+        v.insert<uint64_t> ("c.version.minor"),
+        v.insert<uint64_t> ("c.version.patch"),
+        v.insert<string>   ("c.version.build"),
+
+        v.insert<string>   ("c.signature"),
+        v.insert<string>   ("c.checksum"),
+
+        v.insert<string>   ("c.pattern"),
+
+        v.insert<target_triplet> ("c.target"),
+
+        v.insert<string>   ("c.target.cpu"),
+        v.insert<string>   ("c.target.vendor"),
+        v.insert<string>   ("c.target.system"),
+        v.insert<string>   ("c.target.version"),
+        v.insert<string>   ("c.target.class")
+      };
+
+      // Alias some cc. variables as c.
+      //
+      v.insert_alias (d.c_runtime, "c.runtime");
+
+      assert (mod == nullptr);
+      config_module* m (new config_module (move (d)));
+      mod.reset (m);
+      m->guess (rs, loc, hints);
+      return true;
+    }
+
+    bool
+    config_init (scope& rs,
+                 scope& bs,
+                 const location& loc,
+                 unique_ptr<module_base>&,
+                 bool,
+                 bool,
+                 const variable_map& hints)
+    {
+      tracer trace ("c::config_init");
+      l5 ([&]{trace << "for " << bs;});
+
+      // We only support root loading (which means there can only be one).
+      //
+      if (&rs != &bs)
+        fail (loc) << "c.config module must be loaded in project root";
+
+      // Load c.guess.
+      //
+      if (!cast_false<bool> (rs["c.guess.loaded"]))
+        load_module (rs, rs, "c.guess", loc, false, hints);
+
+      config_module& cm (*rs.lookup_module<config_module> ("c.guess"));
+      cm.init (rs, loc, hints);
+      return true;
+    }
+
+    static const target_type* const hdr[] =
+    {
+      &h::static_type,
+      nullptr
+    };
+
+    static const target_type* const inc[] =
+    {
+      &h::static_type,
+      &c::static_type,
+      nullptr
+    };
+
+    bool
+    init (scope& rs,
+          scope& bs,
+          const location& loc,
+          unique_ptr<module_base>& mod,
+          bool,
+          bool,
+          const variable_map& hints)
+    {
+      tracer trace ("c::init");
+      l5 ([&]{trace << "for " << bs;});
+
+      // We only support root loading (which means there can only be one).
+      //
+      if (&rs != &bs)
+        fail (loc) << "c module must be loaded in project root";
+
+      // Load c.config.
+      //
+      if (!cast_false<bool> (rs["c.config.loaded"]))
+        load_module (rs, rs, "c.config", loc, false, hints);
+
+      config_module& cm (*rs.lookup_module<config_module> ("c.guess"));
+
+      cc::data d {
+        cm,
+
+        "c.compile",
+        "c.link",
+        "c.install",
+        "c.uninstall",
+
+        cm.ci_->id.type,
+        cm.ci_->id.variant,
+        cm.ci_->class_,
+        cm.ci_->version.major,
+        cm.ci_->version.minor,
+        cast<process_path>   (rs[cm.x_path]),
+        cast<target_triplet> (rs[cm.x_target]),
+
+        cm.tstd,
+
+        false, // No C modules yet.
+        false, // No __symexport support since no modules.
+
+        cast<dir_paths> (rs[cm.x_sys_lib_dirs]),
+        cast<dir_paths> (rs[cm.x_sys_inc_dirs]),
+
+        cm.sys_lib_dirs_extra,
+        cm.sys_inc_dirs_extra,
+
+        c::static_type,
+        nullptr,        // No C modules yet.
+        hdr,
+        inc
+      };
+
+      assert (mod == nullptr);
+      module* m;
+      mod.reset (m = new module (move (d)));
+      m->init (rs, loc, hints);
+      return true;
+    }
+
+    static const module_functions mod_functions[] =
+    {
+      // NOTE: don't forget to also update the documentation in init.hxx if
+      //       changing anything here.
+
+      {"c.guess",  nullptr, guess_init},
+      {"c.config", nullptr, config_init},
+      {"c",        nullptr, init},
+      {nullptr,    nullptr, nullptr}
+    };
+
+    const module_functions*
+    build2_c_load ()
+    {
+      return mod_functions;
+    }
+  }
+}
diff --git a/libbuild2/c/init.hxx b/libbuild2/c/init.hxx
new file mode 100644
index 0000000..92d12a3
--- /dev/null
+++ b/libbuild2/c/init.hxx
@@ -0,0 +1,32 @@
+// file      : libbuild2/c/init.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef LIBBUILD2_C_INIT_HXX
+#define LIBBUILD2_C_INIT_HXX
+
+#include <libbuild2/types.hxx>
+#include <libbuild2/utility.hxx>
+
+#include <libbuild2/module.hxx>
+
+#include <libbuild2/c/export.hxx>
+
+namespace build2
+{
+  namespace c
+  {
+    // Module `c` does not require bootstrapping.
+    //
+    // Submodules:
+    //
+    // `c.guess`  -- registers and sets some variables.
+    // `c.config` -- loads c.guess and sets more variables.
+    // `c`        -- loads c.config and registers target types and rules.
+    //
+    extern "C" LIBBUILD2_C_SYMEXPORT const module_functions*
+    build2_c_load ();
+  }
+}
+
+#endif // LIBBUILD2_C_INIT_HXX
diff --git a/libbuild2/c/target.hxx b/libbuild2/c/target.hxx
new file mode 100644
index 0000000..b35beab
--- /dev/null
+++ b/libbuild2/c/target.hxx
@@ -0,0 +1,22 @@
+// file      : libbuild2/c/target.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef LIBBUILD2_C_TARGET_HXX
+#define LIBBUILD2_C_TARGET_HXX
+
+#include <libbuild2/types.hxx>
+#include <libbuild2/utility.hxx>
+
+#include <libbuild2/cc/target.hxx>
+
+namespace build2
+{
+  namespace c
+  {
+    using cc::h;
+    using cc::c;
+  }
+}
+
+#endif // LIBBUILD2_C_TARGET_HXX
diff --git a/libbuild2/module.cxx b/libbuild2/module.cxx
index 4e7080a..37bc817 100644
--- a/libbuild2/module.cxx
+++ b/libbuild2/module.cxx
@@ -39,6 +39,7 @@ namespace build2
   static const char* bundled_modules[] = {
     "bash",
     "bin",
+    "c",
     "cc",
     "in",
     "version"