mex: disk_available

Author: scivision

+stdlib/disk_available.m

@@ -1,5 +1,5 @@
 %% DISK_AVAILABLE disk available space (bytes)
-% requires: java
+% requires: mex or java
 %
 % example:  stdlib.disk_available('/')
 %

buildfile.m

@@ -102,6 +102,7 @@ function publishTask(context)
 ["src/parent.cpp", "src/parent_fs.cpp", normal], ...
 "src/relative_to.cpp", ...
 "src/proximate_to.cpp", ...
+"src/disk_available.cpp", ...
 ["src/is_wsl.cpp", linux], ...
 "src/set_permissions.cpp", ...
 ["src/is_rosetta.cpp", mac], ...

octave_build.m

@@ -11,6 +11,7 @@ function octave_build(overwrite)
 
 %% specific source
 srcs = {
+fullfile(d, "disk_available.cpp"), ...
 fullfile(d, "drop_slash.cpp"), ...
 fullfile(d, "is_wsl.cpp"), ...
 fullfile(d, "is_rosetta.cpp"), ...

src/disk_available.cpp

@@ -0,0 +1,45 @@
+#include "mex.hpp"
+#include "mexAdapter.hpp"
+
+#include <string>
+#include <string_view>
+
+#include <vector>
+#include <memory>
+
+#include <cstdint>
+#include <filesystem>
+#include <system_error>
+
+
+class MexFunction : public matlab::mex::Function {
+public:
+  void operator()(matlab::mex::ArgumentList outputs, matlab::mex::ArgumentList inputs) {
+// boilerplate engine & ArrayFactory setup
+    std::shared_ptr<matlab::engine::MATLABEngine> matlabEng = getEngine();
+
+    matlab::data::ArrayFactory factory;
+// wrangle inputs
+    std::string in;
+
+    if (inputs.size() != 1) {
+      matlabEng->feval(u"error", 0,
+        std::vector<matlab::data::Array>({ factory.createScalar("Mex: One input required") }));
+    }
+    if ((inputs[0].getType() == matlab::data::ArrayType::MATLAB_STRING && inputs[0].getNumberOfElements() == 1)){
+        matlab::data::TypedArray<matlab::data::MATLABString> stringArr = inputs[0];
+        in = stringArr[0];
+    } else if (inputs[0].getType() == matlab::data::ArrayType::CHAR){
+        matlab::data::CharArray charArr = inputs[0];
+        in.assign(charArr.begin(), charArr.end());
+    } else {
+        matlabEng->feval(u"error", 0,
+        std::vector<matlab::data::Array>({ factory.createScalar("Mex: First input must be a scalar string or char vector") }));
+    }
+
+// actual function algorithm / computation
+    std::uintmax_t s = std::filesystem::space(in).available;
+
+    outputs[0] = factory.createScalar(s);
+  }
+};

src/octave/disk_available.cpp

@@ -0,0 +1,19 @@
+#include <octave/oct.h>
+
+#include <string>
+
+#include <filesystem>
+
+
+DEFUN_DLD (disk_available, args, nargout,
+           "disk space available to user")
+{
+  if (args.length() != 1){
+    octave_stdout << "Oct: One input required\n";
+    return octave_value(0);
+  }
+
+  std::uintmax_t s = std::filesystem::space(args(0).string_value()).available;
+
+  return octave_value(s);
+}