If you free an xmlDocPtr before any xmlXPathObjectPtr 's that reference the doc, you'll get valgrind errors like this: ==7390== Invalid read of size 4 ==7390== at 0x4EB8BC6: xmlXPathFreeNodeSet (xpath.c:4185) ==7390== by 0x4EB8CC5: xmlXPathFreeObject (xpath.c:5492) ==7390== by 0x400A56: main (in /tmp/test) ==7390== Address 0x60c0928 is 8 bytes inside a block of size 120 free'd ==7390== at 0x4C29D2A: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==7390== by 0x4E8784F: xmlFreeNodeList (tree.c:3683) ==7390== by 0x4E87605: xmlFreeDoc (tree.c:1242) ==7390== by 0x400A4A: main (in /tmp/test) The following simple test program demonstrates the problem: #include <stdio.h> #include <stdlib.h> #include <assert.h> #include <libxml/xpath.h> int main (int argc, char *argv[]) { xmlDocPtr doc; xmlXPathContextPtr xpathctx; xmlXPathObjectPtr xpathobj; doc = xmlReadMemory ("<test/>", 7, NULL, NULL, XML_PARSE_NONET); assert (doc); xpathctx = xmlXPathNewContext (doc); assert (xpathctx); xpathobj = xmlXPathEvalExpression (BAD_CAST "/test", xpathctx); assert (xpathobj); xmlFreeDoc (doc); xmlXPathFreeObject (xpathobj); xmlXPathFreeContext (xpathctx); exit (EXIT_SUCCESS); } In virt-v2v we were not freeing up objects in the correct order, because we didn't express the dependency between objects at the C level into the OCaml, where the OCaml garbage collector could see those dependencies. For example code like: let doc = ... in let xpathctx = xpath_new_context doc in let xpathobj = xpath_eval_expression xpathctx "/foo" in might end up freeing the 'doc' (xmlDocPtr) if, say, there were no further references to it in the code, before freeing the 'xpathobj' (xmlXPathObjectPtr). To avoid this, we change the OCaml-level representation of objects like xpathobj so they contain a reference back to the higher-level objects (xpathctx & doc). Therefore holding an xpathobj means that the doc cannot be freed. However that alone is not quite sufficient. There is a further problem when the program calls Gc.full_major, Gc.compact etc., or even just when xpathctx & doc happen to be freed at the same time. The GC won't necessarily free them in the right order as it knows both need to be freed but doesn't know that one must be freed before the other. To solve this we have to move the finalisers into OCaml code, since the OCaml Gc.finalise function comes with an explicit ordering guarantee (that finalisers are always called in reverse order that they were created), which the C-level finaliser does not. --- v2v/input_libvirtxml.ml | 18 +++--- v2v/input_ova.ml | 10 ++-- v2v/output_libvirt.ml | 6 +- v2v/test-harness/v2v_test_harness.ml | 2 +- v2v/xml-c.c | 103 ++++++++++++++++++----------------- v2v/xml.ml | 92 ++++++++++++++++++++----------- v2v/xml.mli | 2 +- 7 files changed, 131 insertions(+), 102 deletions(-) diff --git a/v2v/input_libvirtxml.ml b/v2v/input_libvirtxml.ml index ba00d94..646346d 100644 --- a/v2v/input_libvirtxml.ml +++ b/v2v/input_libvirtxml.ml @@ -44,14 +44,14 @@ let parse_libvirt_xml ?conn xml = let obj = Xml.xpath_eval_expression xpathctx expr in if Xml.xpathobj_nr_nodes obj < 1 then default else ( - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in Xml.node_as_string node ) and xpath_to_int expr default = let obj = Xml.xpath_eval_expression xpathctx expr in if Xml.xpathobj_nr_nodes obj < 1 then default else ( - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in let str = Xml.node_as_string node in try int_of_string str with Failure "int_of_string" -> @@ -78,7 +78,7 @@ let parse_libvirt_xml ?conn xml = let obj = Xml.xpath_eval_expression xpathctx "/domain/features/*" in let nr_nodes = Xml.xpathobj_nr_nodes obj in for i = 0 to nr_nodes-1 do - let node = Xml.xpathobj_node doc obj i in + let node = Xml.xpathobj_node obj i in features := Xml.node_name node :: !features done; !features in @@ -89,7 +89,7 @@ let parse_libvirt_xml ?conn xml = if nr_nodes < 1 then None else ( (* Ignore everything except the first <graphics> device. *) - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in Xml.xpathctx_set_current_context xpathctx node; let keymap = match xpath_to_string "@keymap" "" with "" -> None | k -> Some k in @@ -150,7 +150,7 @@ let parse_libvirt_xml ?conn xml = if nr_nodes < 1 then None else ( (* Ignore everything except the first <sound> device. *) - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in Xml.xpathctx_set_current_context xpathctx node; match xpath_to_string "@model" "" with @@ -189,7 +189,7 @@ let parse_libvirt_xml ?conn xml = if nr_nodes < 1 then error (f_"this guest has no non-removable disks"); for i = 0 to nr_nodes-1 do - let node = Xml.xpathobj_node doc obj i in + let node = Xml.xpathobj_node obj i in Xml.xpathctx_set_current_context xpathctx node; let controller = @@ -248,7 +248,7 @@ let parse_libvirt_xml ?conn xml = let obj = Xml.xpath_eval_expression xpathctx expr in if Xml.xpathobj_nr_nodes obj < 1 then default else ( - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in Xml.node_as_string node ) in @@ -279,7 +279,7 @@ let parse_libvirt_xml ?conn xml = let nr_nodes = Xml.xpathobj_nr_nodes obj in let disks = ref [] in for i = 0 to nr_nodes-1 do - let node = Xml.xpathobj_node doc obj i in + let node = Xml.xpathobj_node obj i in Xml.xpathctx_set_current_context xpathctx node; let controller = @@ -309,7 +309,7 @@ let parse_libvirt_xml ?conn xml = let nr_nodes = Xml.xpathobj_nr_nodes obj in let nics = ref [] in for i = 0 to nr_nodes-1 do - let node = Xml.xpathobj_node doc obj i in + let node = Xml.xpathobj_node obj i in Xml.xpathctx_set_current_context xpathctx node; let mac = xpath_to_string "mac/@address" "" in diff --git a/v2v/input_ova.ml b/v2v/input_ova.ml index 066af73..0ef349d 100644 --- a/v2v/input_ova.ml +++ b/v2v/input_ova.ml @@ -184,14 +184,14 @@ object let obj = Xml.xpath_eval_expression xpathctx expr in if Xml.xpathobj_nr_nodes obj < 1 then default else ( - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in Xml.node_as_string node ) and xpath_to_int expr default = let obj = Xml.xpath_eval_expression xpathctx expr in if Xml.xpathobj_nr_nodes obj < 1 then default else ( - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in let str = Xml.node_as_string node in try int_of_string str with Failure "int_of_string" -> @@ -247,7 +247,7 @@ object let obj = Xml.xpath_eval_expression xpathctx expr in let nr_nodes = Xml.xpathobj_nr_nodes obj in for i = 0 to nr_nodes-1 do - let n = Xml.xpathobj_node doc obj i in + let n = Xml.xpathobj_node obj i in Xml.xpathctx_set_current_context xpathctx n; (* XXX We assume the OVF lists these in order. @@ -316,7 +316,7 @@ object let obj = Xml.xpath_eval_expression xpathctx expr in let nr_nodes = Xml.xpathobj_nr_nodes obj in for i = 0 to nr_nodes-1 do - let n = Xml.xpathobj_node doc obj i in + let n = Xml.xpathobj_node obj i in Xml.xpathctx_set_current_context xpathctx n; let id = xpath_to_int "rasd:ResourceType/text()" 0 in assert (id = 14 || id = 15 || id = 16); @@ -350,7 +350,7 @@ object let obj = Xml.xpath_eval_expression xpathctx "/ovf:Envelope/ovf:VirtualSystem/ovf:VirtualHardwareSection/ovf:Item[rasd:ResourceType/text()=10]" in let nr_nodes = Xml.xpathobj_nr_nodes obj in for i = 0 to nr_nodes-1 do - let n = Xml.xpathobj_node doc obj i in + let n = Xml.xpathobj_node obj i in Xml.xpathctx_set_current_context xpathctx n; let vnet = xpath_to_string "rasd:ElementName/text()" (sprintf"eth%d" i) in let nic = { diff --git a/v2v/output_libvirt.ml b/v2v/output_libvirt.ml index a4fa5fb..7f02e45 100644 --- a/v2v/output_libvirt.ml +++ b/v2v/output_libvirt.ml @@ -54,7 +54,7 @@ let target_features_of_capabilities_doc doc arch = warning (f_"the target hypervisor does not support a %s KVM guest") arch; [] ) else ( - let node (* first matching <guest> *) = Xml.xpathobj_node doc obj 0 in + let node (* first matching <guest> *) = Xml.xpathobj_node obj 0 in Xml.xpathctx_set_current_context xpathctx node; (* Get guest/features/* nodes. *) @@ -62,7 +62,7 @@ let target_features_of_capabilities_doc doc arch = let features = ref [] in for i = 0 to Xml.xpathobj_nr_nodes obj - 1 do - let feature_node = Xml.xpathobj_node doc obj i in + let feature_node = Xml.xpathobj_node obj i in let feature_name = Xml.node_name feature_node in features := feature_name :: !features done; @@ -355,7 +355,7 @@ class output_libvirt oc output_pool = object let obj = Xml.xpath_eval_expression xpathctx expr in if Xml.xpathobj_nr_nodes obj < 1 then default else ( - let node = Xml.xpathobj_node doc obj 0 in + let node = Xml.xpathobj_node obj 0 in Xml.node_as_string node ) in diff --git a/v2v/test-harness/v2v_test_harness.ml b/v2v/test-harness/v2v_test_harness.ml index 9ab2de7..efbda7b 100644 --- a/v2v/test-harness/v2v_test_harness.ml +++ b/v2v/test-harness/v2v_test_harness.ml @@ -92,7 +92,7 @@ let run ~test ?input_disk ?input_xml ?(test_plan = default_plan) () = let nodes_of_xpathobj doc xpathobj = let nodes = ref [] in for i = 0 to Xml.xpathobj_nr_nodes xpathobj - 1 do - nodes := Xml.xpathobj_node doc xpathobj i :: !nodes + nodes := Xml.xpathobj_node xpathobj i :: !nodes done; List.rev !nodes in diff --git a/v2v/xml-c.c b/v2v/xml-c.c index 2602766..13627e1 100644 --- a/v2v/xml-c.c +++ b/v2v/xml-c.c @@ -40,60 +40,53 @@ /* xmlDocPtr type */ #define Doc_val(v) (*((xmlDocPtr *)Data_custom_val(v))) -static void -doc_finalize (value docv) -{ - xmlDocPtr doc = Doc_val (docv); - - if (doc) - xmlFreeDoc (doc); -} - static struct custom_operations doc_custom_operations = { (char *) "doc_custom_operations", - doc_finalize, + custom_finalize_default, custom_compare_default, custom_hash_default, custom_serialize_default, custom_deserialize_default }; +value +v2v_xml_free_doc (value docv) +{ + CAMLparam1 (docv); + xmlDocPtr doc = Doc_val (docv); + + xmlFreeDoc (doc); + CAMLreturn (Val_unit); +} + /* xmlXPathContextPtr type */ -#define Xpathctx_val(v) (*((xmlXPathContextPtr *)Data_custom_val(v))) +#define Xpathctx_ptr_val(v) (*((xmlXPathContextPtr *)Data_custom_val(v))) -static void -xpathctx_finalize (value xpathctxv) -{ - xmlXPathContextPtr xpathctx = Xpathctx_val (xpathctxv); - - if (xpathctx) - xmlXPathFreeContext (xpathctx); -} - -static struct custom_operations xpathctx_custom_operations = { - (char *) "xpathctx_custom_operations", - xpathctx_finalize, +static struct custom_operations xpathctx_ptr_custom_operations = { + (char *) "xpathctx_ptr_custom_operations", + custom_finalize_default, custom_compare_default, custom_hash_default, custom_serialize_default, custom_deserialize_default }; +value +v2v_xml_xpathctx_ptr_free_context (value xpathctxv) +{ + CAMLparam1 (xpathctxv); + xmlXPathContextPtr xpathctx = Xpathctx_ptr_val (xpathctxv); + + xmlXPathFreeContext (xpathctx); + CAMLreturn (Val_unit); +} + /* xmlXPathObjectPtr type */ -#define Xpathobj_val(v) (*((xmlXPathObjectPtr *)Data_custom_val(v))) +#define Xpathobj_ptr_val(v) (*((xmlXPathObjectPtr *)Data_custom_val(v))) -static void -xpathobj_finalize (value xpathobjv) -{ - xmlXPathObjectPtr xpathobj = Xpathobj_val (xpathobjv); - - if (xpathobj) - xmlXPathFreeObject (xpathobj); -} - -static struct custom_operations xpathobj_custom_operations = { - (char *) "xpathobj_custom_operations", - xpathobj_finalize, +static struct custom_operations xpathobj_ptr_custom_operations = { + (char *) "xpathobj_ptr_custom_operations", + custom_finalize_default, custom_compare_default, custom_hash_default, custom_serialize_default, @@ -101,6 +94,16 @@ static struct custom_operations xpathobj_custom_operations = { }; value +v2v_xml_xpathobj_ptr_free_object (value xpathobjv) +{ + CAMLparam1 (xpathobjv); + xmlXPathObjectPtr xpathobj = Xpathobj_ptr_val (xpathobjv); + + xmlXPathFreeObject (xpathobj); + CAMLreturn (Val_unit); +} + +value v2v_xml_parse_memory (value xmlv) { CAMLparam1 (xmlv); @@ -159,7 +162,7 @@ v2v_xml_to_string (value docv, value formatv) } value -v2v_xml_xpath_new_context (value docv) +v2v_xml_xpath_new_context_ptr (value docv) { CAMLparam1 (docv); CAMLlocal1 (xpathctxv); @@ -171,21 +174,21 @@ v2v_xml_xpath_new_context (value docv) if (xpathctx == NULL) caml_invalid_argument ("xpath_new_context: unable to create xmlXPathNewContext"); - xpathctxv = caml_alloc_custom (&xpathctx_custom_operations, + xpathctxv = caml_alloc_custom (&xpathctx_ptr_custom_operations, sizeof (xmlXPathContextPtr), 0, 1); - Xpathctx_val (xpathctxv) = xpathctx; + Xpathctx_ptr_val (xpathctxv) = xpathctx; CAMLreturn (xpathctxv); } value -v2v_xml_xpath_register_ns (value xpathctxv, value prefix, value uri) +v2v_xml_xpathctx_ptr_register_ns (value xpathctxv, value prefix, value uri) { CAMLparam3 (xpathctxv, prefix, uri); xmlXPathContextPtr xpathctx; int r; - xpathctx = Xpathctx_val (xpathctxv); + xpathctx = Xpathctx_ptr_val (xpathctxv); r = xmlXPathRegisterNs (xpathctx, BAD_CAST String_val (prefix), BAD_CAST String_val (uri)); if (r == -1) caml_invalid_argument ("xpath_register_ns: unable to register namespace"); @@ -194,30 +197,30 @@ v2v_xml_xpath_register_ns (value xpathctxv, value prefix, value uri) } value -v2v_xml_xpath_eval_expression (value xpathctxv, value exprv) +v2v_xml_xpathctx_ptr_eval_expression (value xpathctxv, value exprv) { CAMLparam2 (xpathctxv, exprv); CAMLlocal1 (xpathobjv); xmlXPathContextPtr xpathctx; xmlXPathObjectPtr xpathobj; - xpathctx = Xpathctx_val (xpathctxv); + xpathctx = Xpathctx_ptr_val (xpathctxv); xpathobj = xmlXPathEvalExpression (BAD_CAST String_val (exprv), xpathctx); if (xpathobj == NULL) caml_invalid_argument ("xpath_eval_expression: unable to evaluate XPath expression"); - xpathobjv = caml_alloc_custom (&xpathobj_custom_operations, + xpathobjv = caml_alloc_custom (&xpathobj_ptr_custom_operations, sizeof (xmlXPathObjectPtr), 0, 1); - Xpathobj_val (xpathobjv) = xpathobj; + Xpathobj_ptr_val (xpathobjv) = xpathobj; CAMLreturn (xpathobjv); } value -v2v_xml_xpathobj_nr_nodes (value xpathobjv) +v2v_xml_xpathobj_ptr_nr_nodes (value xpathobjv) { CAMLparam1 (xpathobjv); - xmlXPathObjectPtr xpathobj = Xpathobj_val (xpathobjv); + xmlXPathObjectPtr xpathobj = Xpathobj_ptr_val (xpathobjv); if (xpathobj->nodesetval == NULL) CAMLreturn (Val_int (0)); @@ -226,10 +229,10 @@ v2v_xml_xpathobj_nr_nodes (value xpathobjv) } value -v2v_xml_xpathobj_get_node_ptr (value xpathobjv, value iv) +v2v_xml_xpathobj_ptr_get_node_ptr (value xpathobjv, value iv) { CAMLparam2 (xpathobjv, iv); - xmlXPathObjectPtr xpathobj = Xpathobj_val (xpathobjv); + xmlXPathObjectPtr xpathobj = Xpathobj_ptr_val (xpathobjv); int i = Int_val (iv); if (i < 0 || i >= xpathobj->nodesetval->nodeNr) @@ -250,7 +253,7 @@ value v2v_xml_xpathctx_set_node_ptr (value xpathctxv, value nodev) { CAMLparam2 (xpathctxv, nodev); - xmlXPathContextPtr xpathctx = Xpathctx_val (xpathctxv); + xmlXPathContextPtr xpathctx = Xpathctx_ptr_val (xpathctxv); xmlNodePtr node = (xmlNodePtr) nodev; xpathctx->node = node; diff --git a/v2v/xml.ml b/v2v/xml.ml index f521c03..9d37d92 100644 --- a/v2v/xml.ml +++ b/v2v/xml.ml @@ -20,59 +20,85 @@ type doc type node_ptr -type xpathctx -type xpathobj +type xpathctx_ptr +type xpathobj_ptr -(* Since node is owned by doc, we have to make that explicit to the - * garbage collector. +(* At the C level, various objects "own" other objects. We have to + * make that ownership explicit to the garbage collector, else we could + * end up freeing an object before all the C references to it are + * freed. *) +type xpathctx = doc * xpathctx_ptr +type xpathobj = xpathctx * xpathobj_ptr type node = doc * node_ptr -external parse_memory : string -> doc = "v2v_xml_parse_memory" -external copy_doc : doc -> recursive:bool -> doc = "v2v_xml_copy_doc" +external free_doc : doc -> unit = "v2v_xml_free_doc" +external _parse_memory : string -> doc = "v2v_xml_parse_memory" +let parse_memory xml = + let doc = _parse_memory xml in + Gc.finalise free_doc doc; + doc +external _copy_doc : doc -> recursive:bool -> doc = "v2v_xml_copy_doc" +let copy_doc doc ~recursive = + let copy = _copy_doc doc ~recursive in + Gc.finalise free_doc copy; + copy external to_string : doc -> format:bool -> string = "v2v_xml_to_string" -external xpath_new_context : doc -> xpathctx = "v2v_xml_xpath_new_context" -external xpath_eval_expression : xpathctx -> string -> xpathobj = "v2v_xml_xpath_eval_expression" -external xpath_register_ns : xpathctx -> string -> string -> unit = "v2v_xml_xpath_register_ns" +external xpathctx_ptr_free_context : xpathctx_ptr -> unit = "v2v_xml_xpathctx_ptr_free_context" +external xpath_new_context_ptr : doc -> xpathctx_ptr = "v2v_xml_xpath_new_context_ptr" +let xpath_new_context doc = + let xpathctx_ptr = xpath_new_context_ptr doc in + Gc.finalise xpathctx_ptr_free_context xpathctx_ptr; + doc, xpathctx_ptr +external xpathctx_ptr_register_ns : xpathctx_ptr -> string -> string -> unit = "v2v_xml_xpathctx_ptr_register_ns" +let xpath_register_ns (_, xpathctx_ptr) prefix uri = + xpathctx_ptr_register_ns xpathctx_ptr prefix uri +external xpathobj_ptr_free_object : xpathobj_ptr -> unit = "v2v_xml_xpathobj_ptr_free_object" +external xpathctx_ptr_eval_expression : xpathctx_ptr -> string -> xpathobj_ptr = "v2v_xml_xpathctx_ptr_eval_expression" +let xpath_eval_expression ((_, xpathctx_ptr) as xpathctx) expr = + let xpathobj_ptr = xpathctx_ptr_eval_expression xpathctx_ptr expr in + Gc.finalise xpathobj_ptr_free_object xpathobj_ptr; + xpathctx, xpathobj_ptr -external xpathobj_nr_nodes : xpathobj -> int = "v2v_xml_xpathobj_nr_nodes" -external xpathobj_get_node_ptr : xpathobj -> int -> node_ptr = "v2v_xml_xpathobj_get_node_ptr" -let xpathobj_node doc xpathobj i = - let n = xpathobj_get_node_ptr xpathobj i in - (doc, n) +external xpathobj_ptr_nr_nodes : xpathobj_ptr -> int = "v2v_xml_xpathobj_ptr_nr_nodes" +let xpathobj_nr_nodes (_, xpathobj_ptr) = + xpathobj_ptr_nr_nodes xpathobj_ptr -external xpathctx_set_node_ptr : xpathctx -> node_ptr -> unit = "v2v_xml_xpathctx_set_node_ptr" -let xpathctx_set_current_context xpathctx (_, node) = - xpathctx_set_node_ptr xpathctx node +external xpathobj_ptr_get_node_ptr : xpathobj_ptr -> int -> node_ptr = "v2v_xml_xpathobj_ptr_get_node_ptr" +let xpathobj_node ((doc, _), xpathobj_ptr) i = + doc, xpathobj_ptr_get_node_ptr xpathobj_ptr i + +external xpathctx_ptr_set_node_ptr : xpathctx_ptr -> node_ptr -> unit = "v2v_xml_xpathctx_set_node_ptr" +let xpathctx_set_current_context (_, xpathctx_ptr) (_, node_ptr) = + xpathctx_ptr_set_node_ptr xpathctx_ptr node_ptr external node_ptr_name : node_ptr -> string = "v2v_xml_node_ptr_name" -let node_name (_, node) = node_ptr_name node +let node_name (_, node_ptr) = node_ptr_name node_ptr external node_ptr_as_string : doc -> node_ptr -> string = "v2v_xml_node_ptr_as_string" -let node_as_string (doc, node) = - node_ptr_as_string doc node +let node_as_string (doc, node_ptr) = node_ptr_as_string doc node_ptr external node_ptr_set_content : node_ptr -> string -> unit = "v2v_xml_node_ptr_set_content" -let node_set_content (doc, node) = node_ptr_set_content node +let node_set_content (doc, node_ptr) = node_ptr_set_content node_ptr external node_ptr_set_prop : node_ptr -> string -> string -> unit = "v2v_xml_node_ptr_set_prop" -let set_prop (doc, node) = node_ptr_set_prop node +let set_prop (doc, node_ptr) = node_ptr_set_prop node_ptr external node_ptr_unlink_node : node_ptr -> unit = "v2v_xml_node_ptr_unlink_node" -let unlink_node (doc, node) = node_ptr_unlink_node node +let unlink_node (doc, node_ptr) = node_ptr_unlink_node node_ptr type uri = { - uri_scheme : string option; - uri_opaque : string option; - uri_authority : string option; - uri_server : string option; - uri_user : string option; - uri_port : int; - uri_path : string option; - uri_fragment : string option; - uri_query_raw : string option; -} + uri_scheme : string option; + uri_opaque : string option; + uri_authority : string option; + uri_server : string option; + uri_user : string option; + uri_port : int; + uri_path : string option; + uri_fragment : string option; + uri_query_raw : string option; + } external parse_uri : string -> uri = "v2v_xml_parse_uri" diff --git a/v2v/xml.mli b/v2v/xml.mli index 8029813..a3a9c01 100644 --- a/v2v/xml.mli +++ b/v2v/xml.mli @@ -40,7 +40,7 @@ val xpath_register_ns : xpathctx -> string -> string -> unit val xpathobj_nr_nodes : xpathobj -> int (** Get the number of nodes in the nodeset of the xmlXPathObjectPtr. *) -val xpathobj_node : doc -> xpathobj -> int -> node +val xpathobj_node : xpathobj -> int -> node (** Get the i'th node in the nodeset of the xmlXPathObjectPtr. *) val xpathctx_set_current_context : xpathctx -> node -> unit -- 2.3.1