[Libguestfs] [PATCH 1/5] v2v: Add convenience functions for parsing xpath expressions.

--- v2v/Makefile.am | 2 +- v2v/utils.ml | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/v2v/Makefile.am b/v2v/Makefile.am index 93d225b..fc893bd 100644 --- a/v2v/Makefile.am +++ b/v2v/Makefile.am @@ -69,8 +69,8 @@ SOURCES_MLI = \ SOURCES_ML = \ stringMap.ml \ types.ml \ - utils.ml \ xml.ml \ + utils.ml \ domainxml.ml \ DOM.ml \ kvmuid.ml \ diff --git a/v2v/utils.ml b/v2v/utils.ml index 4e6befc..e07f7a9 100644 --- a/v2v/utils.ml +++ b/v2v/utils.ml @@ -58,6 +58,40 @@ let uri_quote str = done; String.concat "" (List.rev !xs) +(* Parse an xpath expression and return a string/int. Returns + * Some v or None if the expression doesn't match. + *) +let xpath_string xpathctx expr = + let obj = Xml.xpath_eval_expression xpathctx expr in + if Xml.xpathobj_nr_nodes obj < 1 then None + else ( + let node = Xml.xpathobj_node obj 0 in + Some (Xml.node_as_string node) + ) +let xpath_int xpathctx expr = + let obj = Xml.xpath_eval_expression xpathctx expr in + if Xml.xpathobj_nr_nodes obj < 1 then None + else ( + let node = Xml.xpathobj_node obj 0 in + let str = Xml.node_as_string node in + try Some (int_of_string str) + with Failure "int_of_string" -> + error (f_"expecting XML expression to return an integer (expression: %s, matching string: %s)") + expr str + ) + +(* Parse an xpath expression and return a string/int; if the expression + * doesn't match, return the default. + *) +let xpath_string_default xpathctx expr default = + match xpath_string xpathctx expr with + | None -> default + | Some s -> s +let xpath_int_default xpathctx expr default = + match xpath_int xpathctx expr with + | None -> default + | Some i -> i + external drive_name : int -> string = "v2v_utils_drive_name" external drive_index : string -> int = "v2v_utils_drive_index" -- 2.5.0