######################################################################## # # License: BSD # Created: November 25, 2009 # Author: Francesc Alted - faltet@pytables.com # # $Id$ # ######################################################################## """Cython functions and classes for supporting links in HDF5.""" from .exceptions import HDF5ExtError from .hdf5extension cimport Node from .utilsextension cimport cstr_to_pystr from libc.stdlib cimport malloc, free from libc.string cimport strlen from cpython.unicode cimport PyUnicode_DecodeUTF8 from .definitions cimport (H5P_DEFAULT, hid_t, herr_t, hbool_t, int64_t, H5T_cset_t, haddr_t) #---------------------------------------------------------------------- # External declarations cdef extern from "H5Lpublic.h" nogil: ctypedef enum H5L_type_t: H5L_TYPE_ERROR = (-1), # Invalid link type id H5L_TYPE_HARD = 0, # Hard link id H5L_TYPE_SOFT = 1, # Soft link id H5L_TYPE_EXTERNAL = 64, # External link id H5L_TYPE_MAX = 255 # Maximum link type id # Information struct for link (for H5Lget_info) cdef union _add_u: haddr_t address # Address hard link points to size_t val_size # Size of a soft link or UD link value ctypedef struct H5L_info_t: H5L_type_t type # Type of link hbool_t corder_valid # Indicate if creation order is valid int64_t corder # Creation order H5T_cset_t cset # Character set of link name _add_u u # Size of a soft link or UD link value # Operations with links herr_t H5Lcreate_hard( hid_t obj_loc_id, char *obj_name, hid_t link_loc_id, char *link_name, hid_t lcpl_id, hid_t lapl_id) herr_t H5Lcreate_soft( char *target_path, hid_t link_loc_id, char *link_name, hid_t lcpl_id, hid_t lapl_id) herr_t H5Lcreate_external( char *file_name, char *object_name, hid_t link_loc_id, char *link_name, hid_t lcpl_id, hid_t lapl_id) herr_t H5Lget_info( hid_t link_loc_id, char *link_name, H5L_info_t *link_buff, hid_t lapl_id) herr_t H5Lget_val( hid_t link_loc_id, char *link_name, void *linkval_buff, size_t size, hid_t lapl_id) herr_t H5Lunpack_elink_val( char *ext_linkval, size_t link_size, unsigned *flags, const char **filename, const char **obj_path) herr_t H5Lcopy( hid_t src_loc_id, char *src_name, hid_t dest_loc_id, char *dest_name, hid_t lcpl_id, hid_t lapl_id) #---------------------------------------------------------------------- # Helper functions def _get_link_class(parent_id, name): """Guess the link class.""" cdef herr_t ret cdef H5L_info_t link_buff cdef H5L_type_t link_type ret = H5Lget_info(parent_id, name, &link_buff, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to get info about link") link_type = link_buff.type if link_type == H5L_TYPE_SOFT: return "SoftLink" elif link_type == H5L_TYPE_EXTERNAL: return "ExternalLink" # elif link_type == H5L_TYPE_HARD: # return "HardLink" else: return "UnImplemented" def _g_create_hard_link(parentnode, str name, targetnode): """Create a hard link in the file.""" cdef herr_t ret cdef bytes encoded_name = name.encode('utf-8') cdef bytes encoded_v_name = targetnode._v_name.encode('utf-8') ret = H5Lcreate_hard(targetnode._v_parent._v_objectid, encoded_v_name, parentnode._v_objectid, encoded_name, H5P_DEFAULT, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to create HDF5 hard link") #---------------------------------------------------------------------- # Public classes cdef class Link(Node): """Extension class from which all link extensions inherits.""" def _g_copy(self, newparent, newname, recursive, _log=True, **kwargs): """Private part for the _f_copy() method.""" cdef herr_t ret cdef object stats cdef bytes encoded_name, encoded_newname encoded_name = self.name.encode('utf-8') encoded_newname = newname.encode('utf-8') # @TODO: set property list --> utf-8 ret = H5Lcopy(self.parent_id, encoded_name, newparent._v_objectid, encoded_newname, H5P_DEFAULT, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to copy HDF5 link") # Update statistics if needed. stats = kwargs.get('stats', None) if stats is not None: stats['links'] += 1 return newparent._v_file.get_node(newparent, newname) cdef class SoftLink(Link): """Extension class representing a soft link.""" def _g_create(self): """Create the link in file.""" cdef herr_t ret cdef bytes encoded_name = self.name.encode('utf-8') cdef bytes encoded_target = self.target.encode('utf-8') ret = H5Lcreate_soft(encoded_target, self.parent_id, encoded_name, H5P_DEFAULT, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to create HDF5 soft link") return 0 # Object ID is zero'ed, as HDF5 does not assign one for links def _g_open(self): """Open the link in file.""" cdef herr_t ret cdef H5L_info_t link_buff cdef size_t val_size cdef char *clinkval cdef bytes encoded_name encoded_name = self.name.encode('utf-8') ret = H5Lget_info(self.parent_id, encoded_name, &link_buff, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to get info about soft link") val_size = link_buff.u.val_size clinkval = malloc(val_size) ret = H5Lget_val(self.parent_id, encoded_name, clinkval, val_size, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to get target value") self.target = PyUnicode_DecodeUTF8(clinkval, strlen(clinkval), NULL) # Release resources free(clinkval) return 0 # Object ID is zero'ed, as HDF5 does not assign one for links cdef class ExternalLink(Link): """Extension class representing an external link.""" def _g_create(self): """Create the link in file.""" cdef herr_t ret cdef bytes encoded_name, encoded_filename, encoded_target encoded_name = self.name.encode('utf-8') filename, target = self._get_filename_node() encoded_filename = filename.encode('utf-8') encoded_target = target.encode('utf-8') ret = H5Lcreate_external(encoded_filename, encoded_target, self.parent_id, encoded_name, H5P_DEFAULT, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to create HDF5 external link") return 0 # Object ID is zero'ed, as HDF5 does not assign one for links def _g_open(self): """Open the link in file.""" cdef herr_t ret cdef H5L_info_t link_buff cdef size_t val_size cdef char *clinkval cdef char *cfilename cdef char *c_obj_path cdef unsigned flags cdef bytes encoded_name cdef str filename, obj_path encoded_name = self.name.encode('utf-8') ret = H5Lget_info(self.parent_id, encoded_name, &link_buff, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to get info about external link") val_size = link_buff.u.val_size clinkval = malloc(val_size) ret = H5Lget_val(self.parent_id, encoded_name, clinkval, val_size, H5P_DEFAULT) if ret < 0: raise HDF5ExtError("failed to get target value") ret = H5Lunpack_elink_val(clinkval, val_size, &flags, &cfilename, &c_obj_path) if ret < 0: raise HDF5ExtError("failed to unpack external link value") filename = cstr_to_pystr(cfilename) obj_path = cstr_to_pystr(c_obj_path) self.target = filename+':'+obj_path # Release resources free(clinkval) return 0 # Object ID is zero'ed, as HDF5 does not assign one for links ## Local Variables: ## mode: python ## py-indent-offset: 2 ## tab-width: 2 ## fill-column: 78 ## End: