Adding function prototypes with this patch.

This helps ctypes know the calling conventions it should use to communicate
with the binary interface of libgfapi and which types it should allocate and
cast. Without it, ctypes fails/crashes when not running on the main thread.

Change-Id: I73480229f451167377ed4d1534b08b66c689cc4f
Signed-off-by: Humble Chirammal <hchiramm@redhat.com>

1 files changed, 244 insertions, 0 deletions

diff --git a/glusterfs/api.py b/glusterfs/api.py
new file mode 100755
index 0000000..fa3c9f7
--- /dev/null
+++ b/glusterfs/api.py
@@ -0,0 +1,244 @@
+
+# Copyright (c) 2012-2014 Red Hat, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+import ctypes
+from ctypes.util import find_library
+
+
+# Looks like ctypes is having trouble with dependencies, so just force them to
+# load with RTLD_GLOBAL until I figure that out.
+client = ctypes.CDLL(find_library("gfapi"), ctypes.RTLD_GLOBAL, use_errno=True)
+# The above statement "may" fail with OSError on some systems if libgfapi.so
+# is located in /usr/local/lib/. This happens when glusterfs is installed from
+# source. Refer to: http://bugs.python.org/issue18502
+
+# Wow, the Linux kernel folks really play nasty games with this structure.  If
+# you look at the man page for stat(2) and then at this definition you'll note
+# two discrepancies.  First, we seem to have st_nlink and st_mode reversed.  In
+# fact that's exactly how they're defined *for 64-bit systems*; for 32-bit
+# they're in the man-page order.  Even uglier, the man page makes no mention of
+# the *nsec fields, but they are very much present and if they're not included
+# then we get memory corruption because libgfapi has a structure definition
+# that's longer than ours and they overwrite some random bit of memory after
+# the space we allocated.  Yes, that's all very disgusting, and I'm still not
+# sure this will really work on 32-bit because all of the field types are so
+# obfuscated behind macros and feature checks.
+
+
+class Stat (ctypes.Structure):
+    _fields_ = [
+        ("st_dev", ctypes.c_ulong),
+        ("st_ino", ctypes.c_ulong),
+        ("st_nlink", ctypes.c_ulong),
+        ("st_mode", ctypes.c_uint),
+        ("st_uid", ctypes.c_uint),
+        ("st_gid", ctypes.c_uint),
+        ("st_rdev", ctypes.c_ulong),
+        ("st_size", ctypes.c_ulong),
+        ("st_blksize", ctypes.c_ulong),
+        ("st_blocks", ctypes.c_ulong),
+        ("st_atime", ctypes.c_ulong),
+        ("st_atimensec", ctypes.c_ulong),
+        ("st_mtime", ctypes.c_ulong),
+        ("st_mtimensec", ctypes.c_ulong),
+        ("st_ctime", ctypes.c_ulong),
+        ("st_ctimensec", ctypes.c_ulong),
+    ]
+
+
+class Statvfs (ctypes.Structure):
+    _fields_ = [
+        ("f_bsize", ctypes.c_ulong),
+        ("f_frsize", ctypes.c_ulong),
+        ("f_blocks", ctypes.c_ulong),
+        ("f_bfree", ctypes.c_ulong),
+        ("f_bavail", ctypes.c_ulong),
+        ("f_files", ctypes.c_ulong),
+        ("f_ffree", ctypes.c_ulong),
+        ("f_favail", ctypes.c_ulong),
+        ("f_fsid", ctypes.c_ulong),
+        ("f_flag", ctypes.c_ulong),
+        ("f_namemax", ctypes.c_ulong),
+        ("__f_spare", ctypes.c_int * 6),
+    ]
+
+
+class Dirent (ctypes.Structure):
+    _fields_ = [
+        ("d_ino", ctypes.c_ulong),
+        ("d_off", ctypes.c_ulong),
+        ("d_reclen", ctypes.c_ushort),
+        ("d_type", ctypes.c_char),
+        ("d_name", ctypes.c_char * 256),
+    ]
+
+# Define function prototypes for the wrapper functions.
+
+glfs_init = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p)(('glfs_init', client))
+
+glfs_statvfs = ctypes.CFUNCTYPE(ctypes.c_int,
+                                ctypes.c_void_p,
+                                ctypes.c_char_p,
+                                ctypes.c_void_p)(('glfs_statvfs', client))
+
+glfs_new = ctypes.CFUNCTYPE(
+    ctypes.c_void_p, ctypes.c_char_p)(('glfs_new', client))
+
+glfs_set_volfile_server = ctypes.CFUNCTYPE(ctypes.c_int,
+                                           ctypes.c_void_p,
+                                           ctypes.c_char_p,
+                                           ctypes.c_char_p,
+                                           ctypes.c_int)(('glfs_set_volfile_server', client))  # noqa
+
+glfs_set_logging = ctypes.CFUNCTYPE(ctypes.c_int,
+                                    ctypes.c_void_p,
+                                    ctypes.c_char_p,
+                                    ctypes.c_int)(('glfs_set_logging', client))
+
+glfs_fini = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p)(('glfs_fini', client))
+
+
+glfs_close = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p)(('glfs_close', client))
+
+glfs_lstat = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_char_p,
+                              ctypes.POINTER(Stat))(('glfs_lstat', client))
+
+glfs_stat = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_char_p,
+                             ctypes.POINTER(Stat))(('glfs_stat', client))
+
+glfs_fstat = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.POINTER(
+    Stat))(('glfs_fstat', client))
+
+glfs_chown = ctypes.CFUNCTYPE(ctypes.c_int,
+                              ctypes.c_void_p,
+                              ctypes.c_char_p,
+                              ctypes.c_uint,
+                              ctypes.c_uint)(('glfs_chown', client))
+
+glfs_lchown = ctypes.CFUNCTYPE(ctypes.c_int,
+                               ctypes.c_void_p,
+                               ctypes.c_char_p,
+                               ctypes.c_uint,
+                               ctypes.c_uint)(('glfs_lchown', client))
+
+glfs_fchown = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_uint,
+                               ctypes.c_uint)(('glfs_fchown', client))
+
+glfs_dup = ctypes.CFUNCTYPE(
+    ctypes.c_void_p, ctypes.c_void_p)(('glfs_dup', client))
+
+glfs_fdatasync = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p)(('glfs_fdatasync', client))
+
+glfs_fsync = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p)(('glfs_fsync', client))
+
+glfs_lseek = ctypes.CFUNCTYPE(ctypes.c_ulong, ctypes.c_void_p, ctypes.c_ulong,
+                              ctypes.c_int)(('glfs_lseek', client))
+
+glfs_read = ctypes.CFUNCTYPE(ctypes.c_size_t,
+                             ctypes.c_void_p,
+                             ctypes.c_void_p,
+                             ctypes.c_size_t,
+                             ctypes.c_int)(('glfs_read', client))
+
+glfs_write = ctypes.CFUNCTYPE(ctypes.c_size_t,
+                              ctypes.c_void_p,
+                              ctypes.c_void_p,
+                              ctypes.c_size_t,
+                              ctypes.c_int)(('glfs_write', client))
+
+glfs_getxattr = ctypes.CFUNCTYPE(ctypes.c_size_t,
+                                 ctypes.c_void_p,
+                                 ctypes.c_char_p,
+                                 ctypes.c_char_p,
+                                 ctypes.c_void_p,
+                                 ctypes.c_size_t)(('glfs_getxattr', client))
+
+glfs_listxattr = ctypes.CFUNCTYPE(ctypes.c_size_t,
+                                  ctypes.c_void_p,
+                                  ctypes.c_char_p,
+                                  ctypes.c_void_p,
+                                  ctypes.c_size_t)(('glfs_listxattr', client))
+
+glfs_removexattr = ctypes.CFUNCTYPE(ctypes.c_int,
+                                    ctypes.c_void_p,
+                                    ctypes.c_char_p,
+                                    ctypes.c_char_p)(('glfs_removexattr', client))  # noqa
+
+glfs_setxattr = ctypes.CFUNCTYPE(ctypes.c_int,
+                                 ctypes.c_void_p,
+                                 ctypes.c_char_p,
+                                 ctypes.c_char_p,
+                                 ctypes.c_void_p,
+                                 ctypes.c_size_t,
+                                 ctypes.c_int)(('glfs_setxattr', client))
+
+glfs_rename = ctypes.CFUNCTYPE(ctypes.c_int,
+                               ctypes.c_void_p,
+                               ctypes.c_char_p,
+                               ctypes.c_char_p)(('glfs_rename', client))
+
+glfs_symlink = ctypes.CFUNCTYPE(ctypes.c_int,
+                                ctypes.c_void_p,
+                                ctypes.c_char_p,
+                                ctypes.c_char_p)(('glfs_symlink', client))
+
+glfs_unlink = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p, ctypes.c_char_p)(('glfs_unlink', client))
+
+glfs_readdir_r = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p,
+                                  ctypes.POINTER(Dirent),
+                                  ctypes.POINTER(ctypes.POINTER(Dirent)))(('glfs_readdir_r', client))  # noqa
+
+glfs_closedir = ctypes.CFUNCTYPE(
+    ctypes.c_int, ctypes.c_void_p)(('glfs_closedir', client))
+
+
+glfs_mkdir = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_char_p,
+                              ctypes.c_ulong)(('glfs_mkdir', client))
+
+glfs_opendir = ctypes.CFUNCTYPE(ctypes.c_void_p,
+                                ctypes.c_void_p,
+                                ctypes.c_char_p)(('glfs_opendir', client))
+
+glfs_rmdir = ctypes.CFUNCTYPE(ctypes.c_int,
+                              ctypes.c_void_p,
+                              ctypes.c_char_p)(('glfs_rmdir', client))
+
+
+# TODO: creat and open fails on test_create_file_already_exists & test_open_file_not_exist functional testing, # noqa
+# when defined via function prototype.. Need to find RCA. For time being, using it from 'api.glfs_' # noqa
+#_glfs_creat = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.c_void_p, ctypes.c_char_p, ctypes.c_int, ctypes.c_uint) # noqa
+                              # (('glfs_creat', client)) # noqa
+#_glfs_open = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.c_void_p, ctypes.c_char_p, ctypes.c_int) # noqa
+#                               (('glfs_open', client)) # noqa
+# TODO: # discard and fallocate fails with "AttributeError: /lib64/libgfapi.so.0: undefined symbol: glfs_discard", # noqa
+#  for time being, using it from api.* # noqa
+# glfs_discard = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_ulong, ctypes.c_size_t)(('glfs_discard', client)) # noqa
+#_glfs_fallocate = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_int, ctypes.c_ulong, ctypes.c_size_t) # noqa
+#                                   (('glfs_fallocate', client)) # noqa
+
+
+#glfs_creat = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.c_void_p, ctypes.c_char_p, ctypes.c_int, ctypes.c_uint)(('glfs_creat', client)) # noqa
+#glfs_open = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.c_void_p, ctypes.c_char_p, ctypes.c_int)(('glfs_open', client)) # noqa
+
+#glfs_discard = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_ulong, ctypes.c_size_t)(('glfs_discard', client)) # noqa
+#glfs_fallocate = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p, ctypes.c_int, ctypes.c_ulong, ctypes.c_size_t)(('glfs_fallocate', client)) # noqa