More adventures with C++/CLI

I’ve been working with C++/CLI to get access to native API functionality from C# some more lately. I’ve been running into cases where something compiles flawlessly when I create the project but then fails miserably when pulled from GIT clean and rebuilt. I’m looking at various build issues that might be contributing to this and will hopefully find the right recipe soon.

Some notes here related to parts that matter and APIs that I’m looking to use…half of this for my own reference as I mess with solutions to see what works:

Marshaling strings the (relatively) easy way:

 #include <msclr/marshal.h>

System::String^ myPath = "ABC";
std::wstring path = msclr::interop::marshal_as(myPath);

File information:

typedef struct _FILE_ID_INFO {
ULONGLONG VolumeSerialNumber;
FILE_ID_128 FileId;


BOOL ok = GetFileInformationByHandleEx(myHandle, FileIdInfo, &info, sizeof(info));

Alternate string marshaling:

inline void MarshalString(String ^ s, std::wstring& os) {
using namespace Runtime::InteropServices;
const wchar_t* chars =
(const wchar_t)Marshal::StringToHGlobalUni(s)).ToPointer();
os = chars;

Volume information:

BOOL ok = GetVolumeInformationW(path.c_str(),
volumeNameBuffer, MAX_PATH + 1,
filesSystemName, MAX_PATH + 1);

File attributes (can be used on c:\ to find things like volume creation time stamp)

BOOL ok(GetFileAttributesExW(path.c_str(),
static_cast<void *>(&info)));

creationDate = gcnew System::DateTime((long long)(info.ftCreationTime.dwLowDateTime) | ((long long)(info.ftCreationTime.dwHighDateTime) << 32));

Additional volume information:

    wchar_t volumeName[1024];     wchar_t fsName[1024];     DWORD vsn;     DWORD fsflags;     BOOL ok(GetVolumeInformationW(path.c_str(),         volumeName, 1024,         &vsn,         nullptr,         &fsflags,         fsName, 1024));


    ULARGE_INTEGER free;     ULARGE_INTEGER total;     ULARGE_INTEGER totalfree;     BOOL ok(GetDiskFreeSpaceExW(path.c_str(), &free, &total, &totalfree));

and basic info

BOOL ok(GetFileInformationByHandleEx(handle, FileBasicInfo, static_cast(&info), sizeof(info)));

Busy week and weekend

…of work related C# and java code. Things stay busy and old projects need additional work as changes happen.

Spent a good chunk of the weekend and several nights last week making sure that work priorities were attended to.

Less fun than messing with sandbox projects, but work does generally come first at the end of the day. Toy projects can slip schedules almost indefinitely…

Started adding mongodb support to C# code

I started adding in concrete MongoDB support to the tool code I’m building. Last night I incorporated the drivers into the solution and set up the connection code for the database. My initial attempt to directly use the C++/CLI object to push a record into the database failed but I expect to add a class that is properly serializable to BSON tonight and get volume information persistence working. I still need to get a better handle on updates in MongoDB. I know there are various sorts of atomic test and set sorts of operations on documents and in order to make this work properly with concurrent access, I need to understand those operations and use them to ensure that updates don’t ‘walk’ on themselves.

When I have a bit more time to type, I’ll add in more details on the MongoDB driver work and the approaches I’m using.

Looking forward to 2019

Well, 2018 was a bit tumultuous. Lots of high points and a similar number of disappointments. I feel as if I’m ending this year about even with where I began it. Some wins, some losses, mostly evening out overall.

Hoping for more from the year coming up. The gyrations of the previous year have helped to shake out some things that needed shaking out. Expectations are set more reasonably and I think the coming year will move more steadily forward along a less erratic course.

I’m expecting a productive year with things better squared away and the path forward clearer that it has been for some time. Lots to get to…much of it potentially exciting.

This last year I wrapped up the program I had been running as software lead. Lots of C#, WPF and Angular running medical robotics with a team of three software engineers working for me. Since that rolled to a successful close I’ve been filling as as an individual contributor on a Java based instrumentation program. Hoping that the new year will bring in a new challenge as this program is wrapped up and handed off. Plenty of challenges to tackle and lots of diversity in the work ahead.

I’m looking to get my RapRap build rolling on the home front. I’ve had most of the relevant electronics around for some time but have always had other priorities bumping work on the 3D printer aside. This year I have friends who are willing to help out with the build and my basement work-bench cleared and ready for action. I’ll need to order parts and run through the build process, but I expect that things will go more smoothly at this point than they have in some time.

I’ve spent a chunk of time over the KMC holiday break (KMC usually keeps enough scheduled holidays in reserve to shut down for the week between Christmas and New Years) getting some progress on file management tools I’ve been playing with for some time. Hoping this time that I’ll get some completed tools running to assist in managing the current sprawl of files on my machines here.

I’m also hoping to get around to some real VR coding this year. I’ve had an HTC Vive here for some time. This year its time to lay down some code and play with this thing’s capabilities in a real way. I expect Unity will likely be a reasonable platform to build things on. I’m also expecting to put more time into learning blender and improving my drawing skills to support the effort. Time will tell where this might go, but there’s plenty to play with.

I’ve poked at VHDL a bit over the last year. I have a break-out board with a Xilinx FPGA on it in my drawer here. I’m not sure whether any more work on this front will happen this year as I expect other priorities to dominate…but again, time will tell.

I also expect to get back to doing more photography. I’ve fallen out of the habit of taking pictures just for the sake of making pretty shots. I need to spend a bit more time in the coming year making art in addition to building code and learning tools…need to find a balance here as with all things.