From 11c0cce6018e05a92719d6989826ccc2a8f23c81 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cristian=20Rodr=C3=ADguez?= <crrodriguez@opensuse.org>
Date: Thu, 2 Feb 2012 00:57:32 -0300
Subject: [PATCH 5/6] Add symbol versioning

---
 configure.ac            |   84 ++++++++----------------------
 m4/ld-version-script.m4 |   53 +++++++++++++++++++
 m4/visibility.m4        |   78 ++++++++++++++++++++++++++++
 src/Makefile.am         |   11 +++-
 src/libssh2.map         |  132 +++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 294 insertions(+), 64 deletions(-)
 create mode 100644 m4/ld-version-script.m4
 create mode 100644 m4/visibility.m4
 create mode 100644 src/libssh2.map

diff --git a/configure.ac b/configure.ac
index 5f94099..7d51197 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,10 +1,19 @@
-# AC_PREREQ(2.57)
-AC_INIT(libssh2, [-], libssh2-devel@cool.haxx.se)
+AC_INIT([libssh2],[-],[libssh2-devel@cool.haxx.se])
 AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_SRCDIR([src])
-AM_CONFIG_HEADER([src/libssh2_config.h example/libssh2_config.h])
+AC_CONFIG_HEADERS([src/libssh2_config.h example/libssh2_config.h])
 AM_MAINTAINER_MODE
 
+AC_PROG_CC_STDC
+AC_USE_SYSTEM_EXTENSIONS
+AC_SYS_LARGEFILE
+AC_PROG_INSTALL
+AC_PROG_LN_S
+AC_PROG_MAKE_SET
+LT_INIT([win32-dll disable-static pic-only])
+gl_VISIBILITY
+gl_LD_VERSION_SCRIPT
+
 dnl SED is needed by some of the tools
 AC_PATH_PROG( SED, sed, sed-was-not-found-by-configure,
               $PATH:/usr/bin:/usr/local/bin)
@@ -67,30 +76,22 @@ AC_SEARCH_LIBS(inet_addr, nsl)
 
 AC_SUBST(LIBS)
 
-AC_PROG_CC
-AC_PROG_INSTALL
-AC_PROG_LN_S
-AC_PROG_MAKE_SET
 AC_PATH_PROGS(SSHD, [sshd], [],
      [$PATH$PATH_SEPARATOR/usr/libexec$PATH_SEPARATOR]dnl
      [/usr/sbin$PATH_SEPARATOR/usr/etc$PATH_SEPARATOR/etc])
 AM_CONDITIONAL(SSHD, test -n "$SSHD")
-AC_LIBTOOL_WIN32_DLL
-AC_PROG_LIBTOOL
 AC_C_BIGENDIAN
 
-dnl check for how to do large files
-AC_SYS_LARGEFILE
 
 # Configure parameters
 AC_ARG_WITH(libgcrypt,
-  AC_HELP_STRING([--with-libgcrypt],[Use Libgcrypt for crypto]),
+  AS_HELP_STRING([--with-libgcrypt],[Use Libgcrypt for crypto]),
   use_libgcrypt=$withval,use_libgcrypt=auto)
 AC_ARG_WITH(openssl,
-  AC_HELP_STRING([--with-openssl],[Use OpenSSL for crypto]),
+  AS_HELP_STRING([--with-openssl],[Use OpenSSL for crypto]),
   use_openssl=$withval,use_openssl=auto)
 AC_ARG_WITH(libz,
-  AC_HELP_STRING([--with-libz],[Use Libz for compression]),
+  AS_HELP_STRING([--with-libz],[Use Libz for compression]),
   use_libz=$withval,use_libz=auto)
 
 # Look for OpenSSL (default)
@@ -136,15 +137,15 @@ fi
 # Optional Settings
 #
 AC_ARG_ENABLE(crypt-none,
-  AC_HELP_STRING([--enable-crypt-none],[Permit "none" cipher -- NOT RECOMMENDED]),
+  AS_HELP_STRING([--enable-crypt-none],[Permit "none" cipher -- NOT RECOMMENDED]),
   [AC_DEFINE(LIBSSH2_CRYPT_NONE, 1, [Enable "none" cipher -- NOT RECOMMENDED])])
 
 AC_ARG_ENABLE(mac-none,
-  AC_HELP_STRING([--enable-mac-none],[Permit "none" MAC -- NOT RECOMMENDED]),
+  AS_HELP_STRING([--enable-mac-none],[Permit "none" MAC -- NOT RECOMMENDED]),
   [AC_DEFINE(LIBSSH2_MAC_NONE, 1, [Enable "none" MAC -- NOT RECOMMENDED])])
 
 AC_ARG_ENABLE(gex-new,
-  AC_HELP_STRING([--disable-gex-new],[Disable "new" diffie-hellman-group-exchange-sha1 method]),
+  AS_HELP_STRING([--disable-gex-new],[Disable "new" diffie-hellman-group-exchange-sha1 method]),
   [GEX_NEW=$enableval])
 if test "$GEX_NEW" != "no"; then
   AC_DEFINE(LIBSSH2_DH_GEX_NEW, 1, [Enable newer diffie-hellman-group-exchange-sha1 syntax])
@@ -155,8 +156,8 @@ dnl option to switch on compiler debug options
 dnl
 AC_MSG_CHECKING([whether to enable pedantic and debug compiler options])
 AC_ARG_ENABLE(debug,
-AC_HELP_STRING([--enable-debug],[Enable pedantic and debug options])
-AC_HELP_STRING([--disable-debug],[Disable debug options]),
+AS_HELP_STRING([--enable-debug],[Enable pedantic and debug options])
+AS_HELP_STRING([--disable-debug],[Disable debug options]),
 [ case "$enable_debug" in
   no)
        AC_MSG_RESULT(no)
@@ -176,45 +177,6 @@ AC_HELP_STRING([--disable-debug],[Disable debug options]),
        AC_MSG_RESULT(no)
 )
 
-dnl ************************************************************
-dnl Enable hiding of internal symbols in library to reduce its size and
-dnl speed dynamic linking of applications.  This currently is only supported
-dnl on gcc >= 4.0 and SunPro C.
-dnl
-AC_MSG_CHECKING([whether to enable hidden symbols in the library])
-AC_ARG_ENABLE(hidden-symbols,
-AC_HELP_STRING([--enable-hidden-symbols],[Hide internal symbols in library])
-AC_HELP_STRING([--disable-hidden-symbols],[Leave all symbols with default visibility in library]),
-[ case "$enableval" in
-  no)
-       AC_MSG_RESULT(no)
-       ;;
-  *)
-       AC_MSG_CHECKING([whether $CC supports it])
-       if test "$GCC" = yes ; then
-         if $CC --help --verbose 2>&1 | grep fvisibility= > /dev/null ; then
-           AC_MSG_RESULT(yes)
-           AC_DEFINE(LIBSSH2_API, [__attribute__ ((visibility ("default")))], [to make a symbol visible])
-           CFLAGS="$CFLAGS -fvisibility=hidden"
-         else
-            AC_MSG_RESULT(no)
-          fi
-
-       else
-         dnl Test for SunPro cc
-         if $CC 2>&1 | grep flags >/dev/null && $CC -flags | grep xldscope= >/dev/null ; then
-           AC_MSG_RESULT(yes)
-           AC_DEFINE(LIBSSH2_API, [__global], [to make a symbol visible])
-           CFLAGS="$CFLAGS -xldscope=hidden"
-         else
-           AC_MSG_RESULT(no)
-         fi
-       fi
-       ;;
-  esac ],
-       AC_MSG_RESULT(no)
-)
-
 # Checks for header files.
 # AC_HEADER_STDC
 AC_CHECK_HEADERS([errno.h fcntl.h stdio.h stdlib.h unistd.h sys/uio.h])
@@ -254,16 +216,16 @@ AC_CHECK_FUNCS(gettimeofday select strtoll)
 dnl Check for select() into ws2_32 for Msys/Mingw
 if test "$ac_cv_func_select" != "yes"; then
   AC_MSG_CHECKING([for select in ws2_32])
-  AC_TRY_LINK([
+  AC_LINK_IFELSE([AC_LANG_PROGRAM([[
 #ifdef HAVE_WINSOCK2_H
 #ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
 #endif
 #include <winsock2.h>
 #endif
-    ],[
+    ]], [[
       select(0,(fd_set *)NULL,(fd_set *)NULL,(fd_set *)NULL,(struct timeval *)NULL);
-    ],[
+    ]])],[
       AC_MSG_RESULT([yes])
       HAVE_SELECT="1"
       AC_DEFINE_UNQUOTED(HAVE_SELECT, 1,
diff --git a/m4/ld-version-script.m4 b/m4/ld-version-script.m4
new file mode 100644
index 0000000..5ed93ef
--- /dev/null
+++ b/m4/ld-version-script.m4
@@ -0,0 +1,53 @@
+# ld-version-script.m4 serial 3
+dnl Copyright (C) 2008-2012 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Simon Josefsson
+
+# FIXME: The test below returns a false positive for mingw
+# cross-compiles, 'local:' statements does not reduce number of
+# exported symbols in a DLL.  Use --disable-ld-version-script to work
+# around the problem.
+
+# gl_LD_VERSION_SCRIPT
+# --------------------
+# Check if LD supports linker scripts, and define automake conditional
+# HAVE_LD_VERSION_SCRIPT if so.
+AC_DEFUN([gl_LD_VERSION_SCRIPT],
+[
+  AC_ARG_ENABLE([ld-version-script],
+    AS_HELP_STRING([--enable-ld-version-script],
+      [enable linker version script (default is enabled when possible)]),
+      [have_ld_version_script=$enableval], [])
+  if test -z "$have_ld_version_script"; then
+    AC_MSG_CHECKING([if LD -Wl,--version-script works])
+    save_LDFLAGS="$LDFLAGS"
+    LDFLAGS="$LDFLAGS -Wl,--version-script=conftest.map"
+    cat > conftest.map <<EOF
+foo
+EOF
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+                   [accepts_syntax_errors=yes], [accepts_syntax_errors=no])
+    if test "$accepts_syntax_errors" = no; then
+      cat > conftest.map <<EOF
+VERS_1 {
+        global: sym;
+};
+
+VERS_2 {
+        global: sym;
+} VERS_1;
+EOF
+      AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+                     [have_ld_version_script=yes], [have_ld_version_script=no])
+    else
+      have_ld_version_script=no
+    fi
+    rm -f conftest.map
+    LDFLAGS="$save_LDFLAGS"
+    AC_MSG_RESULT($have_ld_version_script)
+  fi
+  AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
+])
diff --git a/m4/visibility.m4 b/m4/visibility.m4
new file mode 100644
index 0000000..c519711
--- /dev/null
+++ b/m4/visibility.m4
@@ -0,0 +1,78 @@
+# visibility.m4 serial 4 (gettext-0.18.2)
+dnl Copyright (C) 2005, 2008, 2010-2012 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+dnl Tests whether the compiler supports the command-line option
+dnl -fvisibility=hidden and the function and variable attributes
+dnl __attribute__((__visibility__("hidden"))) and
+dnl __attribute__((__visibility__("default"))).
+dnl Does *not* test for __visibility__("protected") - which has tricky
+dnl semantics (see the 'vismain' test in glibc) and does not exist e.g. on
+dnl MacOS X.
+dnl Does *not* test for __visibility__("internal") - which has processor
+dnl dependent semantics.
+dnl Does *not* test for #pragma GCC visibility push(hidden) - which is
+dnl "really only recommended for legacy code".
+dnl Set the variable CFLAG_VISIBILITY.
+dnl Defines and sets the variable HAVE_VISIBILITY.
+
+AC_DEFUN([gl_VISIBILITY],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  CFLAG_VISIBILITY=
+  HAVE_VISIBILITY=0
+  if test -n "$GCC"; then
+    dnl First, check whether -Werror can be added to the command line, or
+    dnl whether it leads to an error because of some other option that the
+    dnl user has put into $CC $CFLAGS $CPPFLAGS.
+    AC_MSG_CHECKING([whether the -Werror option is usable])
+    AC_CACHE_VAL([gl_cv_cc_vis_werror], [
+      gl_save_CFLAGS="$CFLAGS"
+      CFLAGS="$CFLAGS -Werror"
+      AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM([[]], [[]])],
+        [gl_cv_cc_vis_werror=yes],
+        [gl_cv_cc_vis_werror=no])
+      CFLAGS="$gl_save_CFLAGS"])
+    AC_MSG_RESULT([$gl_cv_cc_vis_werror])
+    dnl Now check whether visibility declarations are supported.
+    AC_MSG_CHECKING([for simple visibility declarations])
+    AC_CACHE_VAL([gl_cv_cc_visibility], [
+      gl_save_CFLAGS="$CFLAGS"
+      CFLAGS="$CFLAGS -fvisibility=hidden"
+      dnl We use the option -Werror and a function dummyfunc, because on some
+      dnl platforms (Cygwin 1.7) the use of -fvisibility triggers a warning
+      dnl "visibility attribute not supported in this configuration; ignored"
+      dnl at the first function definition in every compilation unit, and we
+      dnl don't want to use the option in this case.
+      if test $gl_cv_cc_vis_werror = yes; then
+        CFLAGS="$CFLAGS -Werror"
+      fi
+      AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[extern __attribute__((__visibility__("hidden"))) int hiddenvar;
+             extern __attribute__((__visibility__("default"))) int exportedvar;
+             extern __attribute__((__visibility__("hidden"))) int hiddenfunc (void);
+             extern __attribute__((__visibility__("default"))) int exportedfunc (void);
+             void dummyfunc (void) {}
+           ]],
+           [[]])],
+        [gl_cv_cc_visibility=yes],
+        [gl_cv_cc_visibility=no])
+      CFLAGS="$gl_save_CFLAGS"])
+    AC_MSG_RESULT([$gl_cv_cc_visibility])
+    if test $gl_cv_cc_visibility = yes; then
+      CFLAG_VISIBILITY="-fvisibility=hidden"
+      HAVE_VISIBILITY=1
+      AC_DEFINE(LIBSSH2_API, [__attribute__ ((visibility ("default")))], [to make a symbol visible])
+    fi
+  fi
+  AC_SUBST([CFLAG_VISIBILITY])
+  AC_SUBST([HAVE_VISIBILITY])
+  AC_DEFINE_UNQUOTED([HAVE_VISIBILITY], [$HAVE_VISIBILITY],
+    [Define to 1 or 0, depending whether the compiler supports simple visibility declarations.])
+])
diff --git a/src/Makefile.am b/src/Makefile.am
index 53fb4e8..4db2638 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -45,6 +45,11 @@ VERSION=-version-info 1:1:0
 # set age to 0. (c:r:a=0)
 #
 
-libssh2_la_LDFLAGS = $(VERSION) -no-undefined \
-	-export-symbols-regex '^libssh2_.*' \
-	$(LTLIBGCRYPT) $(LTLIBSSL) $(LTLIBZ)
+libssh2_la_CFLAGS = $(CFLAG_VISIBILITY)
+libssh2_la_LDFLAGS = $(VERSION) -no-undefined
+if HAVE_LD_VERSION_SCRIPT
+libssh2_la_LDFLAGS += -Wl,--version-script=$(srcdir)/libssh2.map
+else
+libssh2_la_LDFLAGS += -export-symbols-regex '^libssh2_.*'
+endif
+libssh2_la_LIBADD = $(LTLIBGCRYPT) $(LTLIBSSL) $(LTLIBZ)
diff --git a/src/libssh2.map b/src/libssh2.map
new file mode 100644
index 0000000..5639bd1
--- /dev/null
+++ b/src/libssh2.map
@@ -0,0 +1,132 @@
+LIBSSH2_1.3.0 {
+global:
+libssh2_agent_connect;
+libssh2_agent_disconnect;
+libssh2_agent_free;
+libssh2_agent_get_identity;
+libssh2_agent_init;
+libssh2_agent_list_identities;
+libssh2_agent_userauth;
+libssh2_banner_set;
+libssh2_base64_decode;
+libssh2_channel_close;
+libssh2_channel_direct_tcpip_ex;
+libssh2_channel_eof;
+libssh2_channel_flush_ex;
+libssh2_channel_forward_accept;
+libssh2_channel_forward_cancel;
+libssh2_channel_forward_listen_ex;
+libssh2_channel_free;
+libssh2_channel_get_exit_signal;
+libssh2_channel_get_exit_status;
+libssh2_channel_handle_extended_data;
+libssh2_channel_handle_extended_data2;
+libssh2_channel_open_ex;
+libssh2_channel_process_startup;
+libssh2_channel_read_ex;
+libssh2_channel_receive_window_adjust;
+libssh2_channel_receive_window_adjust2;
+libssh2_channel_request_pty_ex;
+libssh2_channel_request_pty_size_ex;
+libssh2_channel_send_eof;
+libssh2_channel_set_blocking;
+libssh2_channel_setenv_ex;
+libssh2_channel_wait_closed;
+libssh2_channel_wait_eof;
+libssh2_channel_window_read_ex;
+libssh2_channel_window_write_ex;
+libssh2_channel_write_ex;
+libssh2_channel_x11_req_ex;
+libssh2_crypt_methods;
+libssh2_exit;
+libssh2_free;
+libssh2_hostkey_hash;
+libssh2_hostkey_methods;
+libssh2_init;
+libssh2_keepalive_config;
+libssh2_keepalive_send;
+libssh2_knownhost_add;
+libssh2_knownhost_addc;
+libssh2_knownhost_check;
+libssh2_knownhost_checkp;
+libssh2_knownhost_del;
+libssh2_knownhost_free;
+libssh2_knownhost_get;
+libssh2_knownhost_init;
+libssh2_knownhost_readfile;
+libssh2_knownhost_readline;
+libssh2_knownhost_writefile;
+libssh2_knownhost_writeline;
+libssh2_md5;
+libssh2_poll;
+libssh2_poll_channel_read;
+libssh2_publickey_add_ex;
+libssh2_publickey_init;
+libssh2_publickey_list_fetch;
+libssh2_publickey_list_free;
+libssh2_publickey_remove_ex;
+libssh2_publickey_shutdown;
+libssh2_scp_recv;
+libssh2_scp_send64;
+libssh2_scp_send_ex;
+libssh2_session_abstract;
+libssh2_session_banner_set;
+libssh2_session_block_directions;
+libssh2_session_callback_set;
+libssh2_session_disconnect_ex;
+libssh2_session_flag;
+libssh2_session_free;
+libssh2_session_get_blocking;
+libssh2_session_get_timeout;
+libssh2_session_handshake;
+libssh2_session_hostkey;
+libssh2_session_init_ex;
+libssh2_session_last_errno;
+libssh2_session_last_error;
+libssh2_session_method_pref;
+libssh2_session_methods;
+libssh2_session_set_blocking;
+libssh2_session_set_timeout;
+libssh2_session_startup;
+libssh2_sftp_close_handle;
+libssh2_sftp_dtor;
+libssh2_sftp_fstat_ex;
+libssh2_sftp_fstatvfs;
+libssh2_sftp_init;
+libssh2_sftp_last_error;
+libssh2_sftp_mkdir_ex;
+libssh2_sftp_open_ex;
+libssh2_sftp_read;
+libssh2_sftp_readdir_ex;
+libssh2_sftp_rename_ex;
+libssh2_sftp_rmdir_ex;
+libssh2_sftp_seek;
+libssh2_sftp_seek64;
+libssh2_sftp_shutdown;
+libssh2_sftp_stat_ex;
+libssh2_sftp_statvfs;
+libssh2_sftp_symlink_ex;
+libssh2_sftp_tell;
+libssh2_sftp_tell64;
+libssh2_sftp_unlink_ex;
+libssh2_sftp_write;
+libssh2_sha1;
+libssh2_trace;
+libssh2_trace_sethandler;
+libssh2_userauth_authenticated;
+libssh2_userauth_hostbased_fromfile_ex;
+libssh2_userauth_keyboard_interactive_ex;
+libssh2_userauth_list;
+libssh2_userauth_password_ex;
+libssh2_userauth_publickey;
+libssh2_userauth_publickey_fromfile_ex;
+libssh2_version;
+local: *;};
+
+LIBSSH2_1.4.0 {
+global: 
+libssh2_session_supported_algs;
+libssh2_session_banner_get;
+libssh2_sftp_get_channel;
+} LIBSSH2_1.3.0;
+
-- 
1.7.7