Add DLL export/import support

17 files changed, 155 insertions, 82 deletions

diff --git a/butl/base64 b/butl/base64
index 7a0e999..8e4f622 100644
--- a/butl/base64
+++ b/butl/base64
@@ -9,6 +9,8 @@
 #include <string>
 #include <vector>
 
+#include <butl/export>
+
 namespace butl
 {
   // Base64-encode a stream or a buffer. Split the output into 76 char-long
@@ -18,13 +20,13 @@ namespace butl
   // if it has badbit, failbit, or eofbit set and throw invalid_argument if
   // that's the case. Otherwise set badbit if the write operation fails.
   //
-  void
+  LIBBUTL_EXPORT void
   base64_encode (std::ostream&, std::istream&);
 
-  std::string
+  LIBBUTL_EXPORT std::string
   base64_encode (std::istream&);
 
-  std::string
+  LIBBUTL_EXPORT std::string
   base64_encode (const std::vector<char>&);
 
   // Base64-decode a stream or a string. Throw invalid_argument if the input
@@ -35,13 +37,13 @@ namespace butl
   // invalid_argument if that's the case. Otherwise set badbit if the write
   // operation fails.
   //
-  void
+  LIBBUTL_EXPORT void
   base64_decode (std::ostream&, std::istream&);
 
-  void
+  LIBBUTL_EXPORT void
   base64_decode (std::ostream&, const std::string&);
 
-  std::vector<char>
+  LIBBUTL_EXPORT std::vector<char>
   base64_decode (const std::string&);
 };
 
diff --git a/butl/buildfile b/butl/buildfile
index 5c939af..7a3c442 100644
--- a/butl/buildfile
+++ b/butl/buildfile
@@ -5,6 +5,7 @@
 lib{butl}:                         \
 {hxx         cxx}{ base64        } \
 {hxx         cxx}{ char-scanner  } \
+{hxx            }{ export        } \
 {hxx         cxx}{ fdstream      } \
 {hxx ixx     cxx}{ filesystem    } \
 {hxx            }{ multi-index   } \
@@ -30,8 +31,15 @@ lib{butl}:                         \
 lib{butl}: file{sha256c.c}
 
 cxx.poptions =+ -I$src_root
+
 lib{butl}: cxx.export.poptions = -I$src_root
 
+liba{hello}: cxx.export.poptions += -DLIBBUTL_STATIC
+libs{hello}: cxx.export.poptions += -DLIBBUTL_SHARED
+
+obja{*}: cxx.poptions += -DLIBBUTL_STATIC_BUILD
+objs{*}: cxx.poptions += -DLIBBUTL_SHARED_BUILD
+
 # Install into the butl/ subdirectory of, say, /usr/include/.
 #
 install.include = $install.include/butl
diff --git a/butl/char-scanner b/butl/char-scanner
index d50745e..a3b1ad7 100644
--- a/butl/char-scanner
+++ b/butl/char-scanner
@@ -9,12 +9,14 @@
 #include <iosfwd>
 #include <cstdint> // uint64_t
 
+#include <butl/export>
+
 namespace butl
 {
   // Low-level character stream scanner. Normally used as a base for
   // higher-level lexers.
   //
-  class char_scanner
+  class LIBBUTL_EXPORT char_scanner
   {
   public:
     char_scanner (std::istream& is): is_ (is) {}
diff --git a/butl/export b/butl/export
new file mode 100644
index 0000000..2b5a5ac
--- /dev/null
+++ b/butl/export
@@ -0,0 +1,37 @@
+// file      : butl/export -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUTL_EXPORT
+#define BUTL_EXPORT
+
+// Normally we don't export class templates (but do complete specializations),
+// inline functions, and classes without any member functions. But in the end
+// it's all trial and error to figure out what VC needs exported.
+
+#if defined(LIBBUTL_STATIC)         // Using static.
+#  define LIBBUTL_EXPORT
+#elif defined(LIBBUTL_STATIC_BUILD) // Building static.
+#  define LIBBUTL_EXPORT
+#elif defined(LIBBUTL_SHARED)       // Using shared.
+#  ifdef _WIN32
+#    define LIBBUTL_EXPORT __declspec(dllimport)
+#  else
+#    define LIBBUTL_EXPORT
+#  endif
+#elif defined(LIBBUTL_SHARED_BUILD) // Building shared.
+#  ifdef _WIN32
+#    define LIBBUTL_EXPORT __declspec(dllexport)
+#  else
+#    define LIBBUTL_EXPORT
+#  endif
+#else
+// If none of the above macros are defined, then we assume we are being using
+// 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 LIBBUTL_EXPORT            // Using static or shared.
+#endif
+
+#endif // BUTL_EXPORT
diff --git a/butl/fdstream b/butl/fdstream
index bb14f25..0caac5c 100644
--- a/butl/fdstream
+++ b/butl/fdstream
@@ -10,6 +10,8 @@
 #include <ostream>
 #include <cstdint> // uint16_t
 
+#include <butl/export>
+
 #include <butl/path>
 #include <butl/filesystem> // permissions
 
@@ -38,7 +40,7 @@ namespace butl
   //   used
   // - not movable, though can be easily supported
   //
-  class fdbuf: public std::basic_streambuf<char>
+  class LIBBUTL_EXPORT fdbuf: public std::basic_streambuf<char>
   {
   public:
     virtual
@@ -111,10 +113,10 @@ namespace butl
     skip   = 0x04
   };
 
-  fdstream_mode operator& (fdstream_mode, fdstream_mode);
-  fdstream_mode operator| (fdstream_mode, fdstream_mode);
-  fdstream_mode operator&= (fdstream_mode&, fdstream_mode);
-  fdstream_mode operator|= (fdstream_mode&, fdstream_mode);
+  inline fdstream_mode operator& (fdstream_mode, fdstream_mode);
+  inline fdstream_mode operator| (fdstream_mode, fdstream_mode);
+  inline fdstream_mode operator&= (fdstream_mode&, fdstream_mode);
+  inline fdstream_mode operator|= (fdstream_mode&, fdstream_mode);
 
   // Extended (compared to ios::openmode) file open flags.
   //
@@ -132,12 +134,12 @@ namespace butl
     none = 0           // Usefull when build the mode incrementally.
   };
 
-  fdopen_mode operator& (fdopen_mode, fdopen_mode);
-  fdopen_mode operator| (fdopen_mode, fdopen_mode);
-  fdopen_mode operator&= (fdopen_mode&, fdopen_mode);
-  fdopen_mode operator|= (fdopen_mode&, fdopen_mode);
+  inline fdopen_mode operator& (fdopen_mode, fdopen_mode);
+  inline fdopen_mode operator| (fdopen_mode, fdopen_mode);
+  inline fdopen_mode operator&= (fdopen_mode&, fdopen_mode);
+  inline fdopen_mode operator|= (fdopen_mode&, fdopen_mode);
 
-  class fdstream_base
+  class LIBBUTL_EXPORT fdstream_base
   {
   protected:
     fdstream_base () = default;
@@ -180,7 +182,7 @@ namespace butl
   // Note that ifdstream destructor will close an open file descriptor but
   // will ignore any errors. To detect such errors, call close() explicitly.
   //
-  class ifdstream: fdstream_base, public std::istream
+  class LIBBUTL_EXPORT ifdstream: fdstream_base, public std::istream
   {
   public:
     // Create an unopened object with iostate = badbit | failbit (we cannot
@@ -260,7 +262,7 @@ namespace butl
   // (std::uncaught_exception() == true). This is enforced with assert() in
   // the ofdstream destructor.
   //
-  class ofdstream: fdstream_base, public std::ostream
+  class LIBBUTL_EXPORT ofdstream: fdstream_base, public std::ostream
   {
   public:
     // Create an unopened object with iostate = badbit | failbit (we cannot
@@ -344,7 +346,7 @@ namespace butl
   // - The fail and eof bits may be left cleared in the stream exception mask
   //   when the function throws because of badbit.
   //
-  ifdstream&
+  LIBBUTL_EXPORT ifdstream&
   getline (ifdstream&, std::string&, char delim = '\n');
 
   // Open a file returning the file descriptor on success and throwing
@@ -363,21 +365,21 @@ namespace butl
   // process' umask, so effective permissions are permissions & ~umask. On
   // Windows permissions other than ru and wu are unlikelly to have effect.
   //
-  int
+  LIBBUTL_EXPORT int
   fdopen (const char*,
           fdopen_mode,
           permissions = permissions::ru | permissions::wu |
                         permissions::rg | permissions::wg |
                         permissions::ro | permissions::wo);
 
-  int
+  LIBBUTL_EXPORT int
   fdopen (const std::string&,
           fdopen_mode,
           permissions = permissions::ru | permissions::wu |
                         permissions::rg | permissions::wg |
                         permissions::ro | permissions::wo);
 
-  int
+  LIBBUTL_EXPORT int
   fdopen (const path&,
           fdopen_mode,
           permissions = permissions::ru | permissions::wu |
@@ -387,15 +389,15 @@ namespace butl
   // Set the translation mode for the file descriptor. Return the previous
   // mode on success, throw ios::failure otherwise.
   //
-  fdstream_mode
+  LIBBUTL_EXPORT fdstream_mode
   fdmode (int, fdstream_mode);
 
   // Convenience functions for setting the translation mode for standard
   // streams.
   //
-  fdstream_mode stdin_fdmode  (fdstream_mode);
-  fdstream_mode stdout_fdmode (fdstream_mode);
-  fdstream_mode stderr_fdmode (fdstream_mode);
+  LIBBUTL_EXPORT fdstream_mode stdin_fdmode  (fdstream_mode);
+  LIBBUTL_EXPORT fdstream_mode stdout_fdmode (fdstream_mode);
+  LIBBUTL_EXPORT fdstream_mode stderr_fdmode (fdstream_mode);
 
   // Low-level, nothrow file descriptor API.
   //
@@ -403,7 +405,7 @@ namespace butl
   // Close the file descriptor. Return true on success, set errno and return
   // false otherwise.
   //
-  bool
+  LIBBUTL_EXPORT bool
   fdclose (int) noexcept;
 
   // Open the null device (e.g., /dev/null) that discards all data written to
@@ -412,7 +414,7 @@ namespace butl
   // Note that it's the caller's responsibility to close the returned file
   // descriptor.
   //
-  int
+  LIBBUTL_EXPORT int
   fdnull () noexcept;
 }
 
diff --git a/butl/filesystem b/butl/filesystem
index 7b23fc5..2c4f3a4 100644
--- a/butl/filesystem
+++ b/butl/filesystem
@@ -25,6 +25,8 @@
 #include <utility>  // move()
 #include <iterator>
 
+#include <butl/export>
+
 #include <butl/path>
 #include <butl/timestamp>
 
@@ -33,13 +35,13 @@ namespace butl
   // Return true if the path is to an existing directory. Note that
   // this function resolves symlinks.
   //
-  bool
+  LIBBUTL_EXPORT bool
   dir_exists (const path&);
 
   // Return true if the path is to an existing regular file. Note that
   // this function resolves symlinks.
   //
-  bool
+  LIBBUTL_EXPORT bool
   file_exists (const path&);
 
   // Try to create a directory unless it already exists. If you expect
@@ -55,13 +57,13 @@ namespace butl
   //
   enum class mkdir_status {success, already_exists};
 
-  mkdir_status
+  LIBBUTL_EXPORT mkdir_status
   try_mkdir (const dir_path&, mode_t = 0777);
 
   // The '-p' version of the above (i.e., it creates the parent
   // directories if necessary).
   //
-  mkdir_status
+  LIBBUTL_EXPORT mkdir_status
   try_mkdir_p (const dir_path&, mode_t = 0777);
 
   // Try to remove the directory returning not_exist if it does not exist
@@ -70,20 +72,20 @@ namespace butl
   //
   enum class rmdir_status {success, not_exist, not_empty};
 
-  rmdir_status
+  LIBBUTL_EXPORT rmdir_status
   try_rmdir (const dir_path&, bool ignore_error = false);
 
   // The '-r' (recursive) version of the above. Note that it will
   // never return not_empty.
   //
-  rmdir_status
+  LIBBUTL_EXPORT rmdir_status
   try_rmdir_r (const dir_path&, bool ignore_error = false);
 
   // As above but throws rather than returns not_exist if the directory
   // does not exist (unless ignore_error is true), so check before calling.
   // If the second argument is false, then the directory itself is not removed.
   //
-  void
+  LIBBUTL_EXPORT void
   rmdir_r (const dir_path&, bool dir = true, bool ignore_error = false);
 
   // Try to remove the file (or symlinks) returning not_exist if
@@ -92,7 +94,7 @@ namespace butl
   //
   enum class rmfile_status {success, not_exist};
 
-  rmfile_status
+  LIBBUTL_EXPORT rmfile_status
   try_rmfile (const path&, bool ignore_error = false);
 
   // Automatically try to remove the path on destruction unless cancelled.
@@ -132,7 +134,7 @@ namespace butl
   //
   // Note that Windows symlinks are currently not supported.
   //
-  void
+  LIBBUTL_EXPORT void
   mksymlink (const path& target, const path& link, bool dir = false);
 
   // Create a symbolic link to a directory. Throw std::system_error on
@@ -151,7 +153,7 @@ namespace butl
   // be a directory. While Windows support directories (via junktions), this
   // is currently not implemented.
   //
-  void
+  LIBBUTL_EXPORT void
   mkhardlink (const path& target, const path& link, bool dir = false);
 
   // Create a hard link to a directory. Throw std::system_error on failures.
@@ -172,10 +174,10 @@ namespace butl
     none = 0
   };
 
-  cpflags operator& (cpflags, cpflags);
-  cpflags operator| (cpflags, cpflags);
-  cpflags operator&= (cpflags&, cpflags);
-  cpflags operator|= (cpflags&, cpflags);
+  inline cpflags operator& (cpflags, cpflags);
+  inline cpflags operator| (cpflags, cpflags);
+  inline cpflags operator&= (cpflags&, cpflags);
+  inline cpflags operator|= (cpflags&, cpflags);
 
   // Copy a regular file, including its permissions. Throw std::system_error
   // on failure. Fail if the destination file exists and the overwrite_content
@@ -192,7 +194,7 @@ namespace butl
   // destination is a dangling symbolic link, then this function will still
   // fail.
   //
-  void
+  LIBBUTL_EXPORT void
   cpfile (const path& from, const path& to, cpflags = cpflags::none);
 
   // Copy a regular file to an existing directory.
@@ -208,7 +210,7 @@ namespace butl
   // by throwing std::system_error. Note that this function resolves
   // symlinks.
   //
-  timestamp
+  LIBBUTL_EXPORT timestamp
   file_mtime (const path&);
 
   // Path permissions.
@@ -232,21 +234,21 @@ namespace butl
     none = 0
   };
 
-  permissions operator& (permissions, permissions);
-  permissions operator| (permissions, permissions);
-  permissions operator&= (permissions&, permissions);
-  permissions operator|= (permissions&, permissions);
+  inline permissions operator& (permissions, permissions);
+  inline permissions operator| (permissions, permissions);
+  inline permissions operator&= (permissions&, permissions);
+  inline permissions operator|= (permissions&, permissions);
 
   // Get path permissions. Throw std::system_error on failure. Note that this
   // function resolves symlinks.
   //
-  permissions
+  LIBBUTL_EXPORT permissions
   path_permissions (const path&);
 
   // Set path permissions. Throw std::system_error on failure. Note that this
   // function resolves symlinks.
   //
-  void
+  LIBBUTL_EXPORT void
   path_permissions (const path&, permissions);
 
   // Directory entry iteration.
@@ -260,7 +262,7 @@ namespace butl
     other
   };
 
-  class dir_entry
+  class LIBBUTL_EXPORT dir_entry
   {
   public:
     typedef butl::path path_type;
@@ -299,7 +301,7 @@ namespace butl
     dir_path b_;
   };
 
-  class dir_iterator
+  class LIBBUTL_EXPORT dir_iterator
   {
   public:
     typedef dir_entry value_type;
diff --git a/butl/optional b/butl/optional
index 86bbe59..0ae7e7b 100644
--- a/butl/optional
+++ b/butl/optional
@@ -12,7 +12,7 @@ namespace butl
   // Simple optional class template while waiting for std::optional.
   //
   struct nullopt_t {constexpr nullopt_t (int) {}};
-  constexpr nullopt_t nullopt = 1;
+  constexpr const nullopt_t nullopt = 1;
 
   template <typename T>
   class optional
diff --git a/butl/pager b/butl/pager
index 0414e0a..64a36ca 100644
--- a/butl/pager
+++ b/butl/pager
@@ -9,6 +9,8 @@
 #include <vector>
 #include <iostream>
 
+#include <butl/export>
+
 #include <butl/process>
 #include <butl/fdstream>
 
@@ -42,7 +44,7 @@ namespace butl
   //   cerr << "pager error: " << e.what () << endl;
   // }
   //
-  class pager: protected std::streambuf
+  class LIBBUTL_EXPORT pager: protected std::streambuf
   {
   public:
     ~pager () {wait (true);}
diff --git a/butl/path b/butl/path
index 7562dac..9a75b5d 100644
--- a/butl/path
+++ b/butl/path
@@ -12,6 +12,8 @@
 #include <exception>
 #include <functional> // hash
 
+#include <butl/export>
+
 namespace butl
 {
 
@@ -25,7 +27,7 @@ namespace butl
   // p -= ".*"; // base
   //
 
-  class invalid_path_base: std::exception
+  class LIBBUTL_EXPORT invalid_path_base: std::exception
   {
   public:
     virtual char const*
diff --git a/butl/path.cxx b/butl/path.cxx
index 1693c86..46e36fd 100644
--- a/butl/path.cxx
+++ b/butl/path.cxx
@@ -28,6 +28,8 @@
 #include <cassert>
 #include <system_error>
 
+#include <butl/export>
+
 #include <butl/process>
 
 #ifndef _WIN32
@@ -55,7 +57,7 @@ namespace butl
   //
 
   template <>
-  path_traits<char>::string_type path_traits<char>::
+  LIBBUTL_EXPORT path_traits<char>::string_type path_traits<char>::
   current ()
   {
     // @@ throw system_error (and in the other current() versions).
@@ -74,7 +76,7 @@ namespace butl
   }
 
   template <>
-  void path_traits<char>::
+  LIBBUTL_EXPORT void path_traits<char>::
   current (string_type const& s)
   {
 #ifdef _WIN32
@@ -140,7 +142,7 @@ namespace butl
 #endif
 
   template <>
-  path_traits<char>::string_type path_traits<char>::
+  LIBBUTL_EXPORT path_traits<char>::string_type path_traits<char>::
   temp_directory ()
   {
 #ifdef _WIN32
@@ -162,7 +164,7 @@ namespace butl
   static atomic<size_t> temp_name_count;
 
   template <>
-  path_traits<char>::string_type path_traits<char>::
+  LIBBUTL_EXPORT path_traits<char>::string_type path_traits<char>::
   temp_name (string_type const& prefix)
   {
     return prefix
@@ -171,7 +173,7 @@ namespace butl
   }
 
   template <>
-  path_traits<char>::string_type path_traits<char>::
+  LIBBUTL_EXPORT path_traits<char>::string_type path_traits<char>::
   home ()
   {
 #ifndef _WIN32
@@ -197,7 +199,7 @@ namespace butl
 
 #ifndef _WIN32
   template <>
-  void path_traits<char>::
+  LIBBUTL_EXPORT void path_traits<char>::
   realize (string_type& s)
   {
     char r[PATH_MAX];
@@ -221,7 +223,7 @@ namespace butl
   //
 
   template <>
-  path_traits<wchar_t>::string_type path_traits<wchar_t>::
+  LIBBUTL_EXPORT path_traits<wchar_t>::string_type path_traits<wchar_t>::
   current ()
   {
 #ifdef _WIN32
@@ -242,7 +244,7 @@ namespace butl
   }
 
   template <>
-  void path_traits<wchar_t>::
+  LIBBUTL_EXPORT void path_traits<wchar_t>::
   current (string_type const& s)
   {
 #ifdef _WIN32
@@ -262,7 +264,7 @@ namespace butl
   }
 
   template <>
-  path_traits<wchar_t>::string_type path_traits<wchar_t>::
+  LIBBUTL_EXPORT path_traits<wchar_t>::string_type path_traits<wchar_t>::
   temp_directory ()
   {
 #ifdef _WIN32
@@ -295,7 +297,7 @@ namespace butl
   }
 
   template <>
-  path_traits<wchar_t>::string_type path_traits<wchar_t>::
+  LIBBUTL_EXPORT path_traits<wchar_t>::string_type path_traits<wchar_t>::
   temp_name (string_type const& prefix)
   {
     return prefix +
@@ -304,7 +306,7 @@ namespace butl
   }
 
   template <>
-  path_traits<wchar_t>::string_type path_traits<wchar_t>::
+  LIBBUTL_EXPORT path_traits<wchar_t>::string_type path_traits<wchar_t>::
   home ()
   {
 #ifndef _WIN32
@@ -339,7 +341,7 @@ namespace butl
 
 #ifndef _WIN32
   template <>
-  void path_traits<wchar_t>::
+  LIBBUTL_EXPORT void path_traits<wchar_t>::
   realize (string_type&)
   {
     assert (false); // Implement if/when needed.
diff --git a/butl/process b/butl/process
index e864b53..fc8c1e8 100644
--- a/butl/process
+++ b/butl/process
@@ -13,9 +13,11 @@
 #include <cstdint> // uint32_t
 #include <system_error>
 
+#include <butl/export>
+
 namespace butl
 {
-  struct process_error: std::system_error
+  struct LIBBUTL_EXPORT process_error: std::system_error
   {
     bool
     child () const {return child_;}
@@ -34,7 +36,7 @@ namespace butl
     bool child_;
   };
 
-  class process
+  class LIBBUTL_EXPORT process
   {
   public:
     // Start another process using the specified command line. The default
diff --git a/butl/sha256 b/butl/sha256
index a1d0c38..77fa6bd 100644
--- a/butl/sha256
+++ b/butl/sha256
@@ -10,6 +10,8 @@
 #include <cstdint>
 #include <cstddef> // size_t
 
+#include <butl/export>
+
 namespace butl
 {
   // SHA256 checksum calculator.
@@ -19,7 +21,7 @@ namespace butl
   //
   // cerr << sha256 ("123").string () << endl;
   //
-  class sha256
+  class LIBBUTL_EXPORT sha256
   {
   public:
     sha256 ();
@@ -85,14 +87,14 @@ namespace butl
   // like 01:AB:CD:...). Throw invalid_argument if the argument is not a valid
   // SHA256 string.
   //
-  std::string
+  LIBBUTL_EXPORT std::string
   sha256_to_fingerprint (const std::string&);
 
   // Convert a fingerprint (32 colon-separated hex digit pairs) to the SHA256
   // string representation (64 lower case hex digits). Throw invalid_argument
   // if the argument is not a valid fingerprint.
   //
-  std::string
+  LIBBUTL_EXPORT std::string
   fingerprint_to_sha256 (const std::string&);
 };
 
diff --git a/butl/string-table b/butl/string-table
index d07c75a..cf2a20b 100644
--- a/butl/string-table
+++ b/butl/string-table
@@ -9,6 +9,8 @@
 #include <string>
 #include <unordered_map>
 
+#include <butl/export>
+
 #include <butl/multi-index>
 
 namespace butl
@@ -36,7 +38,7 @@ namespace butl
   struct string_table_traits;
 
   template <>
-  struct string_table_traits<std::string>
+  struct LIBBUTL_EXPORT string_table_traits<std::string>
   {
     static const std::string&
     key (const std::string& d) {return d;}
diff --git a/butl/timestamp b/butl/timestamp
index 02f8a92..04a65b7 100644
--- a/butl/timestamp
+++ b/butl/timestamp
@@ -8,6 +8,8 @@
 #include <chrono>
 #include <iosfwd>
 
+#include <butl/export>
+
 #include <butl/path>
 
 namespace butl
@@ -75,7 +77,7 @@ namespace butl
   //  - support %(N) version for non-optional printing
   //  - support for suffix %[<d>N<s>], for example %[N nsec]
   //
-  std::ostream&
+  LIBBUTL_EXPORT std::ostream&
   to_stream (std::ostream&,
              const timestamp&,
              const char* format,
@@ -88,7 +90,7 @@ namespace butl
     return to_stream (os, ts, "%Y-%m-%d %H:%M:%S%[.N]", true, true);
   }
 
-  std::ostream&
+  LIBBUTL_EXPORT std::ostream&
   operator<< (std::ostream&, const duration&);
 
   // Parse human-readable representation of the timestamp.
@@ -130,7 +132,7 @@ namespace butl
   //   - ability to parse local, return UTC and vice-versa
   //   - handle timezone parsing
   //
-  timestamp
+  LIBBUTL_EXPORT timestamp
   from_string (const char* input,
                const char* format,
                bool local,
diff --git a/butl/triplet b/butl/triplet
index 44b5195..013818e 100644
--- a/butl/triplet
+++ b/butl/triplet
@@ -7,6 +7,8 @@
 
 #include <string>
 
+#include <butl/export>
+
 namespace butl
 {
   // This is the ubiquitous 'target triplet' that loosely has the CPU-VENDOR-OS
@@ -93,7 +95,7 @@ namespace butl
   //
   // 2. LLVM has the Triple class with similar goals.
   //
-  struct triplet
+  struct LIBBUTL_EXPORT triplet
   {
     std::string cpu;
     std::string vendor;
diff --git a/butl/utility b/butl/utility
index efbb13b..2436616 100644
--- a/butl/utility
+++ b/butl/utility
@@ -9,11 +9,13 @@
 #include <utility> // forward()
 #include <cstring> // strcmp
 
+#include <butl/export>
+
 namespace butl
 {
   // Key comparators (i.e., to be used in sets, maps, etc).
   //
-  struct compare_c_string
+  struct LIBBUTL_EXPORT compare_c_string
   {
     bool operator() (const char* x, const char* y) const
     {
@@ -21,7 +23,7 @@ namespace butl
     }
   };
 
-  struct compare_pointer_target
+  struct LIBBUTL_EXPORT compare_pointer_target
   {
     template <typename P>
     bool operator() (const P& x, const P& y) const {return *x < *y;}
diff --git a/butl/win32-utility b/butl/win32-utility
index c74eb66..c446485 100644
--- a/butl/win32-utility
+++ b/butl/win32-utility
@@ -35,14 +35,16 @@
 
 #include <string>
 
+#include <butl/export>
+
 namespace butl
 {
   namespace win32
   {
-    std::string
+    LIBBUTL_EXPORT std::string
     error_msg (DWORD code);
 
-    std::string
+    LIBBUTL_EXPORT std::string
     last_error_msg ();
   }
 };