first shot at interfacing udunits2 directly

DESCRIPTION

@@ -7,7 +7,9 @@ Authors@R: c(person("Edzer", "Pebesma", role = c("aut", "cre"), email = "edzer.p
 Depends:
     R (>= 3.0.0)
 Imports:
-    udunits2 (>= 0.13)
+	Rcpp
+LinkingTo:
+	Rcpp
 Suggests:
     NISTunits,
     measurements,

NAMESPACE

@@ -64,5 +64,6 @@ export(units_options)
 export(valid_udunits)
 export(valid_udunits_prefixes)
 import(stats)
-import(udunits2)
 import(utils)
+importFrom(Rcpp,evalCpp)
+useDynLib(units)

R/RcppExports.R

@@ -0,0 +1,15 @@
+# Generated by using Rcpp::compileAttributes() -> do not edit by hand
+# Generator token: 10BE3573-1514-4C36-9D1C-5A225CD40393
+
+udunits_init <- function(path, warn_on_failure = FALSE) {
+    .Call('_units_udunits_init', PACKAGE = 'units', path, warn_on_failure)
+}
+
+R_ut_parse <- function(name) {
+    .Call('_units_R_ut_parse', PACKAGE = 'units', name)
+}
+
+R_ut_format <- function(p, names = FALSE, definition = FALSE) {
+    .Call('_units_R_ut_format', PACKAGE = 'units', p, names, definition)
+}
+

R/conversion.R

@@ -1,9 +1,3 @@
-NULL
-#' @import utils
-#' @import stats
-#' @import udunits2
-NULL
-
 # Helper functions for testing if we can convert and how using either
 # user-defined conversion functions or udunits.
 are_convertible <- function(from, to) {

R/init.R

@@ -0,0 +1,9 @@
+#' @import utils
+#' @import stats
+#' @importFrom Rcpp evalCpp
+#' @useDynLib units
+NULL
+
+.onLoad = function(libname, pkgname) {
+	udunits_init(character(0), TRUE)
+}

src/Makevars.in

@@ -0,0 +1,2 @@
+PKG_CPPFLAGS = @UD_CPPFLAGS@
+PKG_LIBS = @LIBS@

src/Makevars.win

@@ -0,0 +1,16 @@
+PKG_CPPFLAGS = -I../windows/udunits-2.2.20/include
+PKG_LIBS = -L../windows/udunits-2.2.20/lib${R_ARCH} \
+	-ludunits2 -lexpat
+
+all: clean winlibs
+
+winlibs:
+	"${R_HOME}/bin${R_ARCH_BIN}/Rscript.exe" "../tools/winlibs.R"
+	mkdir -p ../inst
+	rm -Rf ../inst/share
+	cp -r ../windows/udunits-2.2.20/share ../inst/
+
+clean:
+	rm -Rf $(SHLIB) $(OBJECTS)
+
+.PHONY: all winlibs clean

src/RcppExports.cpp

@@ -0,0 +1,55 @@
+// Generated by using Rcpp::compileAttributes() -> do not edit by hand
+// Generator token: 10BE3573-1514-4C36-9D1C-5A225CD40393
+
+#include <Rcpp.h>
+
+using namespace Rcpp;
+
+// udunits_init
+LogicalVector udunits_init(CharacterVector path, bool warn_on_failure);
+RcppExport SEXP _units_udunits_init(SEXP pathSEXP, SEXP warn_on_failureSEXP) {
+BEGIN_RCPP
+    Rcpp::RObject rcpp_result_gen;
+    Rcpp::RNGScope rcpp_rngScope_gen;
+    Rcpp::traits::input_parameter< CharacterVector >::type path(pathSEXP);
+    Rcpp::traits::input_parameter< bool >::type warn_on_failure(warn_on_failureSEXP);
+    rcpp_result_gen = Rcpp::wrap(udunits_init(path, warn_on_failure));
+    return rcpp_result_gen;
+END_RCPP
+}
+// R_ut_parse
+XPtr< std::vector<void *> > R_ut_parse(CharacterVector name);
+RcppExport SEXP _units_R_ut_parse(SEXP nameSEXP) {
+BEGIN_RCPP
+    Rcpp::RObject rcpp_result_gen;
+    Rcpp::RNGScope rcpp_rngScope_gen;
+    Rcpp::traits::input_parameter< CharacterVector >::type name(nameSEXP);
+    rcpp_result_gen = Rcpp::wrap(R_ut_parse(name));
+    return rcpp_result_gen;
+END_RCPP
+}
+// R_ut_format
+CharacterVector R_ut_format(SEXP p, bool names, bool definition);
+RcppExport SEXP _units_R_ut_format(SEXP pSEXP, SEXP namesSEXP, SEXP definitionSEXP) {
+BEGIN_RCPP
+    Rcpp::RObject rcpp_result_gen;
+    Rcpp::RNGScope rcpp_rngScope_gen;
+    Rcpp::traits::input_parameter< SEXP >::type p(pSEXP);
+    Rcpp::traits::input_parameter< bool >::type names(namesSEXP);
+    Rcpp::traits::input_parameter< bool >::type definition(definitionSEXP);
+    rcpp_result_gen = Rcpp::wrap(R_ut_format(p, names, definition));
+    return rcpp_result_gen;
+END_RCPP
+}
+
+static const R_CallMethodDef CallEntries[] = {
+    {"_units_udunits_init", (DL_FUNC) &_units_udunits_init, 2},
+    {"_units_R_ut_parse", (DL_FUNC) &_units_R_ut_parse, 1},
+    {"_units_R_ut_format", (DL_FUNC) &_units_R_ut_format, 3},
+    {NULL, NULL, 0}
+};
+
+RcppExport void R_init_units(DllInfo *dll) {
+    R_registerRoutines(dll, NULL, CallEntries, NULL, NULL);
+    R_useDynamicSymbols(dll, FALSE);
+}

src/io.c

@@ -0,0 +1,35 @@
+#include <R.h>
+#include <udunits2.h>
+#include <stdio.h> /* FILENAME_MAX */
+
+#include "io.h"
+
+/* From the enum comments in udunits2.h */
+const char * ut_status_strings[] = {
+  "Success",
+  "An argument violates the function's contract",
+  "Unit, prefix, or identifier already exists",
+  "No such unit exists",
+  "Operating-system error.  See \"errno\".",
+  "The units belong to different unit-systems",
+  "The operation on the unit(s) is meaningless",
+  "The unit-system doesn't have a unit named \"second\"",
+  "An error occurred while visiting a unit",
+  "A unit can't be formatted in the desired manner",
+  "string unit representation contains syntax error",
+  "string unit representation contains unknown word",
+  "Can't open argument-specified unit database",
+  "Can't open environment-specified unit database",
+  "Can't open installed, default, unit database",
+  "Error parsing unit specification"
+};
+
+void handle_error(const char *calling_function) {
+  ut_status stat;
+  stat = ut_get_status();
+  error("Error in function %s: %s", calling_function, ut_status_strings[stat]);
+}
+
+void r_error_fn(const char* fmt, va_list args) {
+	Rvprintf(fmt, args);
+}

src/io.h

@@ -0,0 +1,2 @@
+void r_error_fn(const char* fmt, va_list args);
+void handle_error(const char *calling_function);

src/udunits.cpp

@@ -0,0 +1,112 @@
+/*
+  modified from: https://github.com/pacificclimate/Rudunits2
+
+  (c) James Hiebert <[email protected]>
+  Pacific Climate Impacts Consortium
+  August, 16, 2010
+
+  Functions to support the R interface to the udunits (API version 2) library
+*/
+
+#include "Rcpp.h"
+using namespace Rcpp;
+
+#include <R.h>
+#include <udunits2.h>
+#include <stdio.h> /* FILENAME_MAX */
+
+ut_system *sys = NULL;
+static ut_encoding enc;
+
+extern "C" {
+#include "io.h"
+}
+
+// [[Rcpp::export]]
+LogicalVector udunits_init(CharacterVector path, bool warn_on_failure = false) {
+
+  LogicalVector ret(1);
+  ut_set_error_message_handler((ut_error_message_handler) r_error_fn);
+  if (sys != NULL)
+    ut_free_system(sys);
+
+  sys = NULL;
+  ut_set_error_message_handler(ut_ignore);
+  for (int i = 0; i < path.size(); i++) {
+    sys = ut_read_xml(path[i]);
+	if (sys != NULL)
+      break;
+  }
+  if (sys == NULL)
+    sys = ut_read_xml(NULL);
+  ut_set_error_message_handler((ut_error_message_handler) r_error_fn);
+  if (sys == NULL) {
+    if (warn_on_failure)
+		handle_error("udunit_init");
+    ret[0] = false;
+  } else
+  	ret[0] = true;
+  enc = UT_UTF8;
+  return ret;
+}
+
+LogicalVector R_ut_has_system(List foo) {
+  LogicalVector ret(1);
+  if (sys != NULL)
+    ret(0) = true;
+  else 
+    ret(0) = false;
+  return ret;
+}
+
+typedef std::vector<void *> ut_vec;
+
+void finalize_ut(ut_vec *v) {
+	for (int i = 0; i < v->size(); i++)
+		ut_free((ut_unit *) ((*v)[i]));
+}
+
+// typedef XPtr<ut_vec,PreserveStorage,finalize_ut> XPtrUT;
+typedef XPtr<ut_vec> XPtrUT;
+
+// [[Rcpp::export]]
+XPtr< std::vector<void *> > R_ut_parse(CharacterVector name) {
+	ut_vec *v = new ut_vec;
+	Rcout << name[0] << std::endl;
+	ut_unit *u = ut_parse(sys, name[0], enc);
+    if (u == NULL) {
+		switch (ut_get_status()) {
+			case UT_BAD_ARG:
+			case UT_SYNTAX:
+			case UT_UNKNOWN:
+			case UT_OS:
+				handle_error("R_ut_parse");
+		}
+	}
+	// error checking ...
+	v->push_back(u);
+	XPtrUT p(v);
+	return(p);
+}
+
+// [[Rcpp::export]]
+CharacterVector R_ut_format(SEXP p, bool names = false, bool definition = false) {
+	XPtr< std::vector<void *> > ptr(p);
+	int opt = enc;
+	if (names)
+		opt = opt | UT_NAMES;
+	if (definition)
+		opt = opt | UT_DEFINITION;
+	char buf[256];
+	int i = ut_format((ut_unit *) (*ptr)[0], buf, 256, opt);
+	if (i == -1) {
+		switch (ut_get_status()) {
+			UT_BAD_ARG:
+			UT_CANT_FORMAT:
+					handle_error("R_ut_format");
+					break;
+			default:;
+		}
+	}
+	return CharacterVector::create(buf);
+}