Move filesystem-related functions from context to new filesystem files

20 files changed, 315 insertions, 275 deletions

diff --git a/build2/algorithm.cxx b/build2/algorithm.cxx
index 5aca7ee..51d2725 100644
--- a/build2/algorithm.cxx
+++ b/build2/algorithm.cxx
@@ -6,12 +6,13 @@
 
 #include <build2/scope>
 #include <build2/target>
-#include <build2/prerequisite>
 #include <build2/rule>
 #include <build2/file> // import()
 #include <build2/search>
 #include <build2/context>
+#include <build2/filesystem>
 #include <build2/diagnostics>
+#include <build2/prerequisite>
 
 using namespace std;
 using namespace butl;
diff --git a/build2/b.cxx b/build2/b.cxx
index 3be9f95..8b3c693 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -11,7 +11,6 @@
 #include <iostream>
 
 #include <butl/pager>
-#include <butl/filesystem>
 
 #include <build2/types>
 #include <build2/utility>
@@ -26,6 +25,7 @@
 #include <build2/file>
 #include <build2/module>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
 #include <build2/context>
 #include <build2/variable>
diff --git a/build2/buildfile b/build2/buildfile
index e1b0b39..d754db2 100644
--- a/build2/buildfile
+++ b/build2/buildfile
@@ -13,6 +13,7 @@ exe{b}:                                    \
         {hxx         cxx}{ diagnostics   } \
         {hxx         cxx}{ dump          } \
         {hxx ixx     cxx}{ file          } \
+	{hxx     txx cxx}{ filesystem    } \
         {hxx         cxx}{ lexer         } \
         {hxx         cxx}{ module        } \
         {hxx ixx     cxx}{ name          } \
diff --git a/build2/cli/rule.cxx b/build2/cli/rule.cxx
index d986eca..139abc6 100644
--- a/build2/cli/rule.cxx
+++ b/build2/cli/rule.cxx
@@ -8,6 +8,7 @@
 #include <build2/target>
 #include <build2/context>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
 
 #include <build2/cli/target>
@@ -319,6 +320,8 @@ namespace build2
       // prerequisites. Also update timestamp in case there are operations
       // after us that could use the information.
       //
+      // @@ Can't we use clean_extra() for this?
+      //
       bool r (false);
 
       if (t.i != nullptr)
diff --git a/build2/cli/target.cxx b/build2/cli/target.cxx
index e3d1526..7432bef 100644
--- a/build2/cli/target.cxx
+++ b/build2/cli/target.cxx
@@ -4,7 +4,7 @@
 
 #include <build2/cli/target>
 
-#include <butl/filesystem>
+#include <build2/filesystem> // file_mtime()
 
 using namespace std;
 using namespace butl;
diff --git a/build2/config/module.cxx b/build2/config/module.cxx
index 4f4064f..9113166 100644
--- a/build2/config/module.cxx
+++ b/build2/config/module.cxx
@@ -4,12 +4,11 @@
 
 #include <build2/config/module>
 
-#include <butl/filesystem>
-
 #include <build2/file>
 #include <build2/rule>
 #include <build2/scope>
 #include <build2/context>
+#include <build2/filesystem> // file_exists()
 #include <build2/diagnostics>
 
 #include <build2/config/operation>
diff --git a/build2/config/operation.cxx b/build2/config/operation.cxx
index 1a207ca..4a5b39c 100644
--- a/build2/config/operation.cxx
+++ b/build2/config/operation.cxx
@@ -7,13 +7,12 @@
 #include <set>
 #include <fstream>
 
-#include <butl/filesystem>
-
 #include <build2/file>
 #include <build2/scope>
 #include <build2/target>
 #include <build2/context>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
 
 #include <build2/config/module>
diff --git a/build2/context b/build2/context
index 3f47af6..dc7d0c0 100644
--- a/build2/context
+++ b/build2/context
@@ -5,10 +5,6 @@
 #ifndef BUILD2_CONTEXT
 #define BUILD2_CONTEXT
 
-#include <type_traits> // enable_if
-
-#include <butl/filesystem>
-
 #include <build2/types>
 #include <build2/utility>
 
@@ -62,73 +58,6 @@ namespace build2
   variable_overrides
   reset (const strings& cmd_vars);
 
-  // The dual interface wrapper for the {mk,rm}{file,dir}() functions
-  // below that allows you to use it as a true/false return or a more
-  // detailed enum from <butl/filesystem>
-  //
-  template <typename T>
-  struct fs_status
-  {
-    T v;
-    fs_status (T v): v (v) {};
-    operator T () const {return v;}
-    explicit operator bool () const {return v == T::success;}
-  };
-
-  // Create the directory and print the standard diagnostics starting from
-  // the specified verbosity level.
-  //
-  // Note that this implementation is not suitable if it is expected that the
-  // directory will exist in the majority of cases and performance is
-  // important. See the fsdir{} rule for details.
-  //
-  using mkdir_status = butl::mkdir_status;
-
-  fs_status<mkdir_status>
-  mkdir (const dir_path&, uint16_t verbosity = 1);
-
-  fs_status<mkdir_status>
-  mkdir_p (const dir_path&, uint16_t verbosity = 1);
-
-  // Remove the file and print the standard diagnostics starting from the
-  // specified verbosity level. The second argument is only used in
-  // diagnostics, to print the target name. Passing the path for target will
-  // result in the relative path being printed.
-  //
-  using rmfile_status = butl::rmfile_status;
-
-  template <typename T>
-  fs_status<rmfile_status>
-  rmfile (const path&, const T& target, uint16_t verbosity = 1);
-
-  inline fs_status<rmfile_status>
-  rmfile (const path& f, int verbosity = 1) // Literal overload (int).
-  {
-    return rmfile (f, f, static_cast<uint16_t> (verbosity));
-  }
-
-  // Similar to rmfile() but for directories (note: not -r).
-  //
-  using rmdir_status = butl::rmdir_status;
-
-  template <typename T>
-  fs_status<rmdir_status>
-  rmdir (const dir_path&, const T& target, uint16_t verbosity = 1);
-
-  inline fs_status<rmdir_status>
-  rmdir (const dir_path& d, int verbosity = 1) // Literal overload (int).
-  {
-    return rmdir (d, d, static_cast<uint16_t> (verbosity));
-  }
-
-  // Remove the directory recursively and print the standard diagnostics
-  // starting from the specified verbosity level. Note that this function
-  // returns not_empty if we try to remove a working directory. If the dir
-  // argument is false, then the directory itself is not removed.
-  //
-  fs_status<rmdir_status>
-  rmdir_r (const dir_path&, bool dir = true, uint16_t verbosity = 1);
-
   // Return the src/out directory corresponding to the given out/src. The
   // passed directory should be a sub-directory of out/src_root.
   //
diff --git a/build2/context.cxx b/build2/context.cxx
index 5530ce3..60e55bd 100644
--- a/build2/context.cxx
+++ b/build2/context.cxx
@@ -325,92 +325,6 @@ namespace build2
     return vos;
   }
 
-  fs_status<mkdir_status>
-  mkdir (const dir_path& d, uint16_t v)
-  {
-    // We don't want to print the command if the directory already exists.
-    // This makes the below code a bit ugly.
-    //
-    mkdir_status ms;
-
-    try
-    {
-      ms = try_mkdir (d);
-    }
-    catch (const system_error& e)
-    {
-      if (verb >= v)
-        text << "mkdir " << d;
-
-      error << "unable to create directory " << d << ": " << e.what ();
-      throw failed ();
-    }
-
-    if (ms == mkdir_status::success)
-    {
-      if (verb >= v)
-        text << "mkdir " << d;
-    }
-
-    return ms;
-  }
-
-  fs_status<mkdir_status>
-  mkdir_p (const dir_path& d, uint16_t v)
-  {
-    // We don't want to print the command if the directory already exists.
-    // This makes the below code a bit ugly.
-    //
-    mkdir_status ms;
-
-    try
-    {
-      ms = try_mkdir_p (d);
-    }
-    catch (const system_error& e)
-    {
-      if (verb >= v)
-        text << "mkdir -p " << d;
-
-      error << "unable to create directory " << d << ": " << e.what ();
-      throw failed ();
-    }
-
-    if (ms == mkdir_status::success)
-    {
-      if (verb >= v)
-        text << "mkdir -p " << d;
-    }
-
-    return ms;
-  }
-
-  fs_status<butl::rmdir_status>
-  rmdir_r (const dir_path& d, bool dir, uint16_t v)
-  {
-    using namespace butl;
-
-    if (work.sub (d)) // Don't try to remove working directory.
-      return rmdir_status::not_empty;
-
-    if (!dir_exists (d))
-      return rmdir_status::not_exist;
-
-    if (verb >= v)
-      text << "rmdir -r " << d;
-
-    try
-    {
-      butl::rmdir_r (d, dir);
-    }
-    catch (const system_error& e)
-    {
-      fail << "unable to remove directory " << d << ": " << e.what ();
-    }
-
-    return rmdir_status::success;
-  }
-
   dir_path
   src_out (const dir_path& out, scope& r)
   {
diff --git a/build2/context.txx b/build2/context.txx
index 9223681..6ff61c9 100644
--- a/build2/context.txx
+++ b/build2/context.txx
@@ -2,109 +2,8 @@
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <build2/diagnostics>
-
 namespace build2
 {
-  template <typename T>
-  fs_status<butl::rmfile_status>
-  rmfile (const path& f, const T& t, uint16_t v)
-  {
-    using namespace butl;
-
-    // We don't want to print the command if we couldn't remove the file
-    // because it does not exist (just like we don't print the update command
-    // if the file is up to date). This makes the below code a bit ugly.
-    //
-    auto print = [&f, &t, v] ()
-    {
-      if (verb >= v)
-      {
-        if (verb >= 2)
-          text << "rm " << f;
-        else if (verb)
-          text << "rm " << t;
-      }
-    };
-
-    rmfile_status rs;
-
-    try
-    {
-      rs = try_rmfile (f);
-    }
-    catch (const system_error& e)
-    {
-      print ();
-      error << "unable to remove file " << f << ": " << e.what ();
-      throw failed ();
-    }
-
-    if (rs == rmfile_status::success)
-      print ();
-
-    return rs;
-  }
-
-  template <typename T>
-  fs_status<butl::rmdir_status>
-  rmdir (const dir_path& d, const T& t, uint16_t v)
-  {
-    using namespace butl;
-
-    bool w (work.sub (d)); // Don't try to remove working directory.
-    rmdir_status rs;
-
-    // We don't want to print the command if we couldn't remove the directory
-    // because it does not exist (just like we don't print mkdir if it already
-    // exists) or if it is not empty. This makes the below code a bit ugly.
-    //
-    auto print = [&d, &t, v] ()
-    {
-      if (verb >= v)
-      {
-        if (verb >= 2)
-          text << "rm " << d;
-        else if (verb)
-          text << "rm " << t;
-      }
-    };
-
-    try
-    {
-      rs = !w ? try_rmdir (d) : rmdir_status::not_empty;
-    }
-    catch (const system_error& e)
-    {
-      print ();
-      error << "unable to remove directory " << d << ": " << e.what ();
-      throw failed ();
-    }
-
-    switch (rs)
-    {
-    case rmdir_status::success:
-      {
-        print ();
-        break;
-      }
-    case rmdir_status::not_empty:
-      {
-        if (verb >= v && verb >= 2)
-        {
-          text << d << " is "
-               << (w ? "current working directory" : "not empty")
-               << ", not removing";
-        }
-        break;
-      }
-    case rmdir_status::not_exist:
-      break;
-    }
-
-    return rs;
-  }
-
   template <typename K>
   basic_path<char, K>
   relative (const basic_path<char, K>& p)
diff --git a/build2/cxx/link.cxx b/build2/cxx/link.cxx
index 4de3194..1818be6 100644
--- a/build2/cxx/link.cxx
+++ b/build2/cxx/link.cxx
@@ -10,14 +10,14 @@
 #include <cstdlib>  // exit()
 
 #include <butl/path-map>
-#include <butl/filesystem>
 
 #include <build2/depdb>
 #include <build2/scope>
+#include <build2/context>
 #include <build2/variable>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
-#include <build2/context>
 
 #include <build2/bin/target>
 #include <build2/cxx/target>
diff --git a/build2/dist/operation.cxx b/build2/dist/operation.cxx
index aea957a..4697c6c 100644
--- a/build2/dist/operation.cxx
+++ b/build2/dist/operation.cxx
@@ -10,6 +10,7 @@
 #include <build2/target>
 #include <build2/context>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
 
 using namespace std;
diff --git a/build2/file.cxx b/build2/file.cxx
index 3195af7..9b3be0c 100644
--- a/build2/file.cxx
+++ b/build2/file.cxx
@@ -7,7 +7,7 @@
 #include <fstream>
 #include <iostream> // cin
 
-#include <butl/filesystem>
+#include <butl/filesystem> // file_exists()
 
 #include <build2/scope>
 #include <build2/context>
diff --git a/build2/filesystem b/build2/filesystem
new file mode 100644
index 0000000..1dcf8bd
--- /dev/null
+++ b/build2/filesystem
@@ -0,0 +1,89 @@
+// file      : build2/filesystem -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_FILESYSTEM
+#define BUILD2_FILESYSTEM
+
+#include <butl/filesystem>
+
+#include <build2/types>
+#include <build2/utility>
+
+// Higher-level filesystem utilities built on top of <butl/filesystem>.
+//
+namespace build2
+{
+  // The dual interface wrapper for the {mk,rm}{file,dir}() functions
+  // below that allows you to use it as a true/false return or a more
+  // detailed enum from <butl/filesystem>
+  //
+  template <typename T>
+  struct fs_status
+  {
+    T v;
+    fs_status (T v): v (v) {};
+    operator T () const {return v;}
+    explicit operator bool () const {return v == T::success;}
+  };
+
+  // Create the directory and print the standard diagnostics starting from
+  // the specified verbosity level.
+  //
+  // Note that this implementation is not suitable if it is expected that the
+  // directory will exist in the majority of cases and performance is
+  // important. See the fsdir{} rule for details.
+  //
+  using mkdir_status = butl::mkdir_status;
+
+  fs_status<mkdir_status>
+  mkdir (const dir_path&, uint16_t verbosity = 1);
+
+  fs_status<mkdir_status>
+  mkdir_p (const dir_path&, uint16_t verbosity = 1);
+
+  // Remove the file and print the standard diagnostics starting from the
+  // specified verbosity level. The second argument is only used in
+  // diagnostics, to print the target name. Passing the path for target will
+  // result in the relative path being printed.
+  //
+  using rmfile_status = butl::rmfile_status;
+
+  template <typename T>
+  fs_status<rmfile_status>
+  rmfile (const path&, const T& target, uint16_t verbosity = 1);
+
+  inline fs_status<rmfile_status>
+  rmfile (const path& f, int verbosity = 1) // Literal overload (int).
+  {
+    return rmfile (f, f, static_cast<uint16_t> (verbosity));
+  }
+
+  // Similar to rmfile() but for directories (note: not -r).
+  //
+  using rmdir_status = butl::rmdir_status;
+
+  template <typename T>
+  fs_status<rmdir_status>
+  rmdir (const dir_path&, const T& target, uint16_t verbosity = 1);
+
+  inline fs_status<rmdir_status>
+  rmdir (const dir_path& d, int verbosity = 1) // Literal overload (int).
+  {
+    return rmdir (d, d, static_cast<uint16_t> (verbosity));
+  }
+
+  // Remove the directory recursively and print the standard diagnostics
+  // starting from the specified verbosity level. Note that this function
+  // returns not_empty if we try to remove a working directory. If the dir
+  // argument is false, then the directory itself is not removed.
+  //
+  // @@ Collides (via ADL) with butl::rmdir_r(), which sucks.
+  //
+  fs_status<rmdir_status>
+  rmdir_r (const dir_path&, bool dir = true, uint16_t verbosity = 1);
+}
+
+#include <build2/filesystem.txx>
+
+#endif // BUILD2_FILESYSTEM
diff --git a/build2/filesystem.cxx b/build2/filesystem.cxx
new file mode 100644
index 0000000..44b0ba4
--- /dev/null
+++ b/build2/filesystem.cxx
@@ -0,0 +1,99 @@
+// file      : build2/filesystem.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/filesystem>
+
+#include <build2/diagnostics>
+
+using namespace std;
+using namespace butl;
+
+namespace build2
+{
+  fs_status<mkdir_status>
+  mkdir (const dir_path& d, uint16_t v)
+  {
+    // We don't want to print the command if the directory already exists.
+    // This makes the below code a bit ugly.
+    //
+    mkdir_status ms;
+
+    try
+    {
+      ms = try_mkdir (d);
+    }
+    catch (const system_error& e)
+    {
+      if (verb >= v)
+        text << "mkdir " << d;
+
+      error << "unable to create directory " << d << ": " << e.what ();
+      throw failed ();
+    }
+
+    if (ms == mkdir_status::success)
+    {
+      if (verb >= v)
+        text << "mkdir " << d;
+    }
+
+    return ms;
+  }
+
+  fs_status<mkdir_status>
+  mkdir_p (const dir_path& d, uint16_t v)
+  {
+    // We don't want to print the command if the directory already exists.
+    // This makes the below code a bit ugly.
+    //
+    mkdir_status ms;
+
+    try
+    {
+      ms = try_mkdir_p (d);
+    }
+    catch (const system_error& e)
+    {
+      if (verb >= v)
+        text << "mkdir -p " << d;
+
+      error << "unable to create directory " << d << ": " << e.what ();
+      throw failed ();
+    }
+
+    if (ms == mkdir_status::success)
+    {
+      if (verb >= v)
+        text << "mkdir -p " << d;
+    }
+
+    return ms;
+  }
+
+  fs_status<butl::rmdir_status>
+  rmdir_r (const dir_path& d, bool dir, uint16_t v)
+  {
+    using namespace butl;
+
+    if (work.sub (d)) // Don't try to remove working directory.
+      return rmdir_status::not_empty;
+
+    if (!dir_exists (d))
+      return rmdir_status::not_exist;
+
+    if (verb >= v)
+      text << "rmdir -r " << d;
+
+    try
+    {
+      butl::rmdir_r (d, dir);
+    }
+    catch (const system_error& e)
+    {
+      fail << "unable to remove directory " << d << ": " << e.what ();
+    }
+
+    return rmdir_status::success;
+  }
+}
diff --git a/build2/filesystem.txx b/build2/filesystem.txx
new file mode 100644
index 0000000..a3366ba
--- /dev/null
+++ b/build2/filesystem.txx
@@ -0,0 +1,108 @@
+// file      : build2/filesystem.txx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/context>     // work
+#include <build2/diagnostics>
+
+namespace build2
+{
+  template <typename T>
+  fs_status<butl::rmfile_status>
+  rmfile (const path& f, const T& t, uint16_t v)
+  {
+    using namespace butl;
+
+    // We don't want to print the command if we couldn't remove the file
+    // because it does not exist (just like we don't print the update command
+    // if the file is up to date). This makes the below code a bit ugly.
+    //
+    auto print = [&f, &t, v] ()
+    {
+      if (verb >= v)
+      {
+        if (verb >= 2)
+          text << "rm " << f;
+        else if (verb)
+          text << "rm " << t;
+      }
+    };
+
+    rmfile_status rs;
+
+    try
+    {
+      rs = try_rmfile (f);
+    }
+    catch (const system_error& e)
+    {
+      print ();
+      error << "unable to remove file " << f << ": " << e.what ();
+      throw failed ();
+    }
+
+    if (rs == rmfile_status::success)
+      print ();
+
+    return rs;
+  }
+
+  template <typename T>
+  fs_status<butl::rmdir_status>
+  rmdir (const dir_path& d, const T& t, uint16_t v)
+  {
+    using namespace butl;
+
+    bool w (work.sub (d)); // Don't try to remove working directory.
+    rmdir_status rs;
+
+    // We don't want to print the command if we couldn't remove the directory
+    // because it does not exist (just like we don't print mkdir if it already
+    // exists) or if it is not empty. This makes the below code a bit ugly.
+    //
+    auto print = [&d, &t, v] ()
+    {
+      if (verb >= v)
+      {
+        if (verb >= 2)
+          text << "rm " << d;
+        else if (verb)
+          text << "rm " << t;
+      }
+    };
+
+    try
+    {
+      rs = !w ? try_rmdir (d) : rmdir_status::not_empty;
+    }
+    catch (const system_error& e)
+    {
+      print ();
+      error << "unable to remove directory " << d << ": " << e.what ();
+      throw failed ();
+    }
+
+    switch (rs)
+    {
+    case rmdir_status::success:
+      {
+        print ();
+        break;
+      }
+    case rmdir_status::not_empty:
+      {
+        if (verb >= v && verb >= 2)
+        {
+          text << d << " is "
+               << (w ? "current working directory" : "not empty")
+               << ", not removing";
+        }
+        break;
+      }
+    case rmdir_status::not_exist:
+      break;
+    }
+
+    return rs;
+  }
+}
diff --git a/build2/install/rule.cxx b/build2/install/rule.cxx
index cbfb105..9157413 100644
--- a/build2/install/rule.cxx
+++ b/build2/install/rule.cxx
@@ -4,11 +4,10 @@
 
 #include <build2/install/rule>
 
-#include <butl/filesystem>
-
 #include <build2/scope>
 #include <build2/target>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
 
 using namespace std;
diff --git a/build2/rule.cxx b/build2/rule.cxx
index 55a35b9..b010ae2 100644
--- a/build2/rule.cxx
+++ b/build2/rule.cxx
@@ -4,13 +4,12 @@
 
 #include <build2/rule>
 
-#include <butl/filesystem>
-
 #include <build2/scope>
 #include <build2/target>
+#include <build2/context>
 #include <build2/algorithm>
+#include <build2/filesystem>
 #include <build2/diagnostics>
-#include <build2/context>
 
 using namespace std;
 using namespace butl;
diff --git a/build2/search.cxx b/build2/search.cxx
index 384bd55..6d0a5e9 100644
--- a/build2/search.cxx
+++ b/build2/search.cxx
@@ -4,7 +4,7 @@
 
 #include <build2/search>
 
-#include <butl/filesystem>
+#include <butl/filesystem> // file_mtime()
 
 #include <build2/scope>
 #include <build2/target>
diff --git a/build2/target.cxx b/build2/target.cxx
index 12bbfd1..deeee4f 100644
--- a/build2/target.cxx
+++ b/build2/target.cxx
@@ -4,7 +4,7 @@
 
 #include <build2/target>
 
-#include <butl/filesystem>
+#include <butl/filesystem> // file_mtime()
 
 #include <build2/scope>
 #include <build2/search>