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-rw-r--r--src/H5L.c179
1 files changed, 179 insertions, 0 deletions
diff --git a/src/H5L.c b/src/H5L.c
index c3c2568..699521f 100644
--- a/src/H5L.c
+++ b/src/H5L.c
@@ -590,6 +590,103 @@ done:
} /* end H5Lcreate_hard() */
/*-------------------------------------------------------------------------
+ * Function: H5Lcreate_external
+ *
+ * Purpose: Creates an external link from LINK_NAME to OBJ_NAME.
+ *
+ * External links are links to objects in other HDF5 files. They
+ * are allowed to "dangle" like soft links internal to a file.
+ * FILE_NAME is the name of the file that OBJ_NAME is is contained
+ * within. If OBJ_NAME is given as a relative path name, the
+ * path will be relative to the root group of FILE_NAME.
+ * LINK_NAME is interpreted relative to LINK_LOC_ID, which is
+ * either a file ID or a group ID.
+ *
+ * Return: Non-negative on success/Negative on failure
+ *
+ * Programmer: Quincey Koziol
+ * Wednesday, May 18, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Lcreate_external(const char *file_name, const char *obj_name, hid_t link_loc_id, const char *link_name,
+ hid_t lcpl_id, hid_t lapl_id)
+{
+ H5VL_object_t * vol_obj = NULL; /* Object of loc_id */
+ H5VL_loc_params_t loc_params;
+ char * norm_obj_name = NULL; /* Pointer to normalized current name */
+ void * ext_link_buf = NULL; /* Buffer to contain external link */
+ size_t buf_size; /* Size of buffer to hold external link */
+ size_t file_name_len; /* Length of file name string */
+ size_t norm_obj_name_len; /* Length of normalized object name string */
+ uint8_t * p; /* Pointer into external link buffer */
+ H5L_type_t link_type = H5L_TYPE_EXTERNAL;
+ herr_t ret_value = SUCCEED; /* Return value */
+
+ FUNC_ENTER_API(FAIL)
+ H5TRACE6("e", "*s*si*sii", file_name, obj_name, link_loc_id, link_name, lcpl_id, lapl_id);
+
+ /* Check arguments */
+ if (!file_name || !*file_name)
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no file name specified")
+ if (!obj_name || !*obj_name)
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no object name specified")
+ if (!link_name || !*link_name)
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no link name specified")
+
+ /* Get the link creation property list */
+ if (H5P_DEFAULT == lcpl_id)
+ lcpl_id = H5P_LINK_CREATE_DEFAULT;
+
+ /* Set the LCPL for the API context */
+ H5CX_set_lcpl(lcpl_id);
+
+ /* Verify access property list and set up collective metadata if appropriate */
+ if (H5CX_set_apl(&lapl_id, H5P_CLS_LACC, link_loc_id, TRUE) < 0)
+ HGOTO_ERROR(H5E_LINK, H5E_CANTSET, FAIL, "can't set access property list info")
+
+ /* Get normalized copy of the link target */
+ if (NULL == (norm_obj_name = H5G_normalize(obj_name)))
+ HGOTO_ERROR(H5E_LINK, H5E_BADVALUE, FAIL, "can't normalize object name")
+
+ /* Combine the filename and link name into a single buffer to give to the UD link */
+ file_name_len = HDstrlen(file_name) + 1;
+ norm_obj_name_len = HDstrlen(norm_obj_name) + 1;
+ buf_size = 1 + file_name_len + norm_obj_name_len;
+ if (NULL == (ext_link_buf = H5MM_malloc(buf_size)))
+ HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "unable to allocate udata buffer")
+
+ /* Encode the external link information */
+ p = (uint8_t *)ext_link_buf;
+ *p++ = (H5L_EXT_VERSION << 4) | H5L_EXT_FLAGS_ALL; /* External link version & flags */
+ HDstrncpy((char *)p, file_name, buf_size - 1); /* Name of file containing external link's object */
+ p += file_name_len;
+ HDstrncpy((char *)p, norm_obj_name, buf_size - (file_name_len + 1)); /* External link's object */
+
+ loc_params.type = H5VL_OBJECT_BY_NAME;
+ loc_params.loc_data.loc_by_name.name = link_name;
+ loc_params.loc_data.loc_by_name.lapl_id = lapl_id;
+ loc_params.obj_type = H5I_get_type(link_loc_id);
+
+ /* get the location object */
+ if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(link_loc_id)))
+ HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
+
+ /* Create an external link */
+ if (H5VL_link_create(H5VL_LINK_CREATE_UD, vol_obj, &loc_params, lcpl_id, lapl_id,
+ H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, (int)link_type, ext_link_buf,
+ buf_size) < 0)
+ HGOTO_ERROR(H5E_LINK, H5E_CANTINIT, FAIL, "unable to create external link")
+
+done:
+ H5MM_xfree(ext_link_buf);
+ H5MM_xfree(norm_obj_name);
+
+ FUNC_LEAVE_API(ret_value)
+} /* end H5Lcreate_external() */
+
+/*-------------------------------------------------------------------------
* Function: H5Lcreate_ud
*
* Purpose: Creates a user-defined link of type LINK_TYPE named LINK_NAME
@@ -1519,6 +1616,88 @@ done:
FUNC_LEAVE_API(ret_value)
} /* end H5Lvisit_by_name2() */
+/*-------------------------------------------------------------------------
+ * Function: H5Lunpack_elink_val
+ *
+ * Purpose: Given a buffer holding the "link value" from an external link,
+ * gets pointers to the information within the link value buffer.
+ *
+ * External link link values contain some flags and
+ * two NULL-terminated strings, one after the other.
+ *
+ * The FLAGS value will be filled in and FILENAME and
+ * OBJ_PATH will be set to pointers within ext_linkval (unless
+ * any of these values is NULL).
+ *
+ * Using this function on strings that aren't external link
+ * udata buffers can result in segmentation faults.
+ *
+ * Return: Non-negative on success/ Negative on failure
+ *
+ * Programmer: James Laird
+ * Monday, July 17, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Lunpack_elink_val(const void *_ext_linkval, size_t link_size, unsigned *flags, const char **filename,
+ const char **obj_path)
+{
+ const uint8_t *ext_linkval = (const uint8_t *)_ext_linkval; /* Pointer to the link value */
+ unsigned lnk_version; /* External link format version */
+ unsigned lnk_flags; /* External link flags */
+ size_t len; /* Length of the filename in the linkval*/
+ herr_t ret_value = SUCCEED; /* Return value */
+
+ FUNC_ENTER_API(FAIL)
+ H5TRACE5("e", "*xz*Iu**s**s", _ext_linkval, link_size, flags, filename, obj_path);
+
+ /* Sanity check external link buffer */
+ if (ext_linkval == NULL)
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not an external link linkval buffer")
+ lnk_version = (*ext_linkval >> 4) & 0x0F;
+ lnk_flags = *ext_linkval & 0x0F;
+ if (lnk_version > H5L_EXT_VERSION)
+ HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, FAIL, "bad version number for external link")
+ if (lnk_flags & (unsigned)~H5L_EXT_FLAGS_ALL)
+ HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, FAIL, "bad flags for external link")
+ if (link_size <= 2)
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a valid external link buffer")
+
+ /* Try to do some error checking. If the last character in the linkval
+ * (the last character of obj_path) isn't NULL, then something's wrong.
+ */
+ if (ext_linkval[link_size - 1] != '\0')
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "linkval buffer is not NULL-terminated")
+
+ /* We're now guaranteed that HDstrlen won't segfault, since the buffer has
+ * at least one NULL in it.
+ */
+ len = HDstrlen((const char *)ext_linkval + 1);
+
+ /* If the first NULL we found was at the very end of the buffer, then
+ * this external link value has no object name and is invalid.
+ */
+ if ((len + 1) >= (link_size - 1))
+ HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "linkval buffer doesn't contain an object path")
+
+ /* If we got here then the buffer contains (at least) two strings packed
+ * in the correct way. Assume it's correct and return pointers to the
+ * filename and object path.
+ */
+ if (filename)
+ *filename = (const char *)ext_linkval + 1;
+ if (obj_path)
+ *obj_path = ((const char *)ext_linkval + 1) + len + 1; /* Add one for NULL terminator */
+
+ /* Set the flags to return */
+ if (flags)
+ *flags = lnk_flags;
+
+done:
+ FUNC_LEAVE_API(ret_value)
+} /* end H5Lunpack_elink_val() */
+
/*
*-------------------------------------------------------------------------
*-------------------------------------------------------------------------