api: versioned symbols in libgfapi.so for compatibility

Use versioned symbols to keep libgfapi at libgfapi.so.0.0.0

Some nits uncovered:

+ there are a couple functions declared that do not have an
  associated definition, e.g. glfs_truncate(), glfs_caller_specific_init()

+ there are five private/internal functions used by heal/src/glfsheal
  and the gfapi master xlator (glfs-master.c): glfs_loc_touchup(),
  glfs_active_subvol(), and glfs_subvol_done(), glfs_init_done(),
  glfs_resolve_at(); which are not declared in glfs.h;

+ for this initial pass at versioned symbols, we use the earliest version
  of all public symbols, i.e. those for which there are declarations in
  glfs.h or glfs-handles.h.
  Further investigation as we do backports to 3.6, 3.4, and 3.4
  will be required to determine if older implementations need to
  be preserved (forward ported) and their associated alias(es) and
  symbol version(s) defined.

FWIW, we should consider linking all of our libraries with a map, it'll
result in a cleaner ABI. Perhaps something for an intern to do or a
Google Summer of Code project.

Change-Id: I513b9aad9c5fd7d8b34ff33acac35f37b6baaab6
BUG: 1160711
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Reviewed-on: http://review.gluster.org/9056
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index f0d04706e77..15896bfc4ea 100644
--- a/.gitignore
+++ b/.gitignore
@@ -48,3 +48,4 @@ ufo/test/unit/.coverage
 xlators/mount/fuse/utils/mount.glusterfs
 xlators/mount/fuse/utils/mount_glusterfs
 xlators/features/glupy/src/setup.py
+api/src/gfapi.map