Split build system into library and driver

1 files changed, 220 insertions, 0 deletions

diff --git a/libbuild2/functions-filesystem.cxx b/libbuild2/functions-filesystem.cxx
new file mode 100644
index 0000000..d98c75d
--- /dev/null
+++ b/libbuild2/functions-filesystem.cxx
@@ -0,0 +1,220 @@
+// file      : libbuild2/functions-filesystem.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <libbutl/filesystem.mxx>
+
+#include <libbuild2/function.hxx>
+#include <libbuild2/variable.hxx>
+
+using namespace std;
+
+namespace build2
+{
+  // Return paths of filesystem entries that match the pattern. See
+  // path_search() overloads (below) for details.
+  //
+  static names
+  path_search (const path& pattern, const optional<dir_path>& start)
+  {
+    names r;
+    auto add = [&r] (path&& p, const std::string&, bool interm) -> bool
+    {
+      // Canonicalizing paths seems to be the right thing to do. Otherwise, we
+      // can end up with different separators in the same path on Windows.
+      //
+      if (!interm)
+        r.emplace_back (
+          value_traits<path>::reverse (move (p.canonicalize ())));
+
+      return true;
+    };
+
+    // Print paths "as is" in the diagnostics.
+    //
+    try
+    {
+      if (pattern.absolute ())
+        path_search (pattern, add);
+      else
+      {
+        // An absolute start directory must be specified for the relative
+        // pattern.
+        //
+        if (!start || start->relative ())
+        {
+          diag_record dr (fail);
+
+          if (!start)
+            dr << "start directory is not specified";
+          else
+            dr << "start directory '" << start->representation ()
+               << "' is relative";
+
+          dr << info << "pattern '" << pattern.representation ()
+             << "' is relative";
+        }
+
+        path_search (pattern, add, *start);
+      }
+    }
+    catch (const system_error& e)
+    {
+      diag_record d (fail);
+      d << "unable to scan";
+
+      // If the pattern is absolute, then the start directory is not used, and
+      // so printing it would be misleading.
+      //
+      if (start && pattern.relative ())
+        d << " '" << start->representation () << "'";
+
+      d << ": " << e
+        << info << "pattern: '" << pattern.representation () << "'";
+    }
+
+    return r;
+  }
+
+  using butl::path_match;
+
+  // Return true if a path for a filesystem entry matches the pattern. See
+  // path_match() overloads (below) for details.
+  //
+  static bool
+  path_match (const path& pattern,
+              const path& entry,
+              const optional<dir_path>& start)
+  {
+    // If pattern and entry are both either absolute or relative and
+    // non-empty, and the first pattern component is not a self-matching
+    // wildcard, then ignore the start directory.
+    //
+    bool rel (pattern.relative () == entry.relative () &&
+              !pattern.empty () && !entry.empty ());
+
+    bool self (!pattern.empty () &&
+               (*pattern.begin ()).find ("***") != string::npos);
+
+    if (rel && !self)
+      return path_match (pattern, entry);
+
+    // The start directory must be specified and be absolute.
+    //
+    if (!start || start->relative ())
+    {
+      diag_record dr (fail);
+
+      // Print paths "as is".
+      //
+      if (!start)
+        dr << "start directory is not specified";
+      else
+        dr << "start directory path '" << start->representation ()
+           << "' is relative";
+
+      dr << info << "pattern: '" << pattern.representation () << "'"
+         << info << "entry: '" << entry.representation () << "'";
+    }
+
+    return path_match (pattern, entry, *start);
+  }
+
+  void
+  filesystem_functions ()
+  {
+    function_family f ("filesystem");
+
+    // path_search
+    //
+    // Return filesystem paths that match the pattern. If the pattern is an
+    // absolute path, then the start directory is ignored (if present).
+    // Otherwise, the start directory must be specified and be absolute.
+    //
+    f["path_search"] = [](path pattern, optional<dir_path> start)
+    {
+      return path_search (pattern, start);
+    };
+
+    f["path_search"] = [](path pattern, names start)
+    {
+      return path_search (pattern, convert<dir_path> (move (start)));
+    };
+
+    f["path_search"] = [](names pattern, optional<dir_path> start)
+    {
+      return path_search (convert<path> (move (pattern)), start);
+    };
+
+    f["path_search"] = [](names pattern, names start)
+    {
+      return path_search (convert<path>     (move (pattern)),
+                          convert<dir_path> (move (start)));
+    };
+
+    // path_match
+    //
+    // Match a filesystem entry name against a name pattern (both are strings),
+    // or a filesystem entry path against a path pattern. For the latter case
+    // the start directory may also be required (see below). The semantics of
+    // the pattern and name/entry arguments is determined according to the
+    // following rules:
+    //
+    // - The arguments must be of the string or path types, or be untyped.
+    //
+    // - If one of the arguments is typed, then the other one must be of the
+    //   same type or be untyped. In the later case, an untyped argument is
+    //   converted to the type of the other argument.
+    //
+    // - If both arguments are untyped and the start directory is specified,
+    //   then the arguments are converted to the path type.
+    //
+    // - If both arguments are untyped and the start directory is not
+    //   specified, then, if one of the arguments is syntactically a path (the
+    //   value contains a directory separator), convert them to the path type,
+    //   otherwise to the string type (match as names).
+    //
+    // If pattern and entry paths are both either absolute or relative and
+    // non-empty, and the first pattern component is not a self-matching
+    // wildcard (doesn't contain ***), then the start directory is not
+    // required, and is ignored if specified. Otherwise, the start directory
+    // must be specified and be an absolute path.
+    //
+    // Name matching.
+    //
+    f["path_match"] = [](string pattern, string name)
+    {
+      return path_match (pattern, name);
+    };
+
+    // Path matching.
+    //
+    f["path_match"] = [](path pat, path ent, optional<dir_path> start)
+    {
+      return path_match (pat, ent, start);
+    };
+
+    // The semantics depends on the presence of the start directory or the
+    // first two argument syntactic representation.
+    //
+    f["path_match"] = [](names pat, names ent, optional<names> start)
+    {
+      auto path_arg = [] (const names& a) -> bool
+      {
+        return a.size () == 1 &&
+        (a[0].directory () ||
+         a[0].value.find_first_of (path::traits_type::directory_separators) !=
+         string::npos);
+      };
+
+      return start || path_arg (pat) || path_arg (ent)
+        ? path_match (convert<path> (move (pat)),   // Match as paths.
+                      convert<path> (move (ent)),
+                      start
+                      ? convert<dir_path> (move (*start))
+                      : optional<dir_path> ())
+        : path_match (convert<string> (move (pat)), // Match as strings.
+                      convert<string> (move (ent)));
+    };
+  }
+}