SetupDiTest.c

#include <stdlib.h>
#include <stdio.h>
#include <Windows.h>
#include <SetupAPI.h>

static int get_interface(HDEVINFO);
static int get_detail(HDEVINFO, PSP_DEVICE_INTERFACE_DATA, PSP_DEVICE_INTERFACE_DETAIL_DATA_A, DWORD);
static int get_instance(HDEVINFO, PSP_DEVINFO_DATA, PSTR, DWORD, PSP_DEVICE_INTERFACE_DETAIL_DATA_A);

int main()
{
    HDEVINFO devInfoSet = SetupDiGetClassDevsA(NULL, "USBSTOR", NULL, DIGCF_ALLCLASSES | DIGCF_PRESENT);
    if (devInfoSet == INVALID_HANDLE_VALUE)
    {
        fprintf(stderr, "SetupDiGetClassDevsA: Error %lu\n", GetLastError());
        return 1;
    }

    int ret = get_interface(devInfoSet);

    SetupDiDestroyDeviceInfoList(devInfoSet);
    return ret;
}

int get_interface(HDEVINFO devInfoSet)
{
    SP_DEVICE_INTERFACE_DATA devIface = { sizeof(SP_DEVICE_INTERFACE_DATA) };
    if (!SetupDiEnumDeviceInterfaces(devInfoSet, NULL, &GUID_DEVINTERFACE_DISK, 0, &devIface))
    {
        fprintf(stderr, "SetupDiEnumDeviceInterfaces: Error %lu\n", GetLastError());
        return 1;
    }

    DWORD sDevIfaceDetail;
    SetupDiGetDeviceInterfaceDetailA(devInfoSet, &devIface, NULL, 0, &sDevIfaceDetail, NULL);

    PSP_DEVICE_INTERFACE_DETAIL_DATA_A pDevIfaceDetail = malloc(sDevIfaceDetail);
    if (!pDevIfaceDetail)
    {
        fputs("malloc: Out of memory.\n", stderr);
        return 1;
    }

    pDevIfaceDetail->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA_A);
    int ret = get_detail(devInfoSet, &devIface, pDevIfaceDetail, sDevIfaceDetail);

    free(pDevIfaceDetail);
    return ret;
}

int get_detail(HDEVINFO devInfoSet, PSP_DEVICE_INTERFACE_DATA pDevIface, PSP_DEVICE_INTERFACE_DETAIL_DATA_A pDevIfaceDetail, DWORD sDevIfaceDetail)
{
    SP_DEVINFO_DATA devInfo = { sizeof(SP_DEVINFO_DATA) };
    if (!SetupDiGetDeviceInterfaceDetailA(devInfoSet, pDevIface, pDevIfaceDetail, sDevIfaceDetail, NULL, &devInfo))
    {
        fprintf(stderr, "SetupDiGetDeviceInterfaceDetailA: Error %lu\n", GetLastError());
        return 1;
    }

    DWORD sDevIfaceId;
    SetupDiGetDeviceInstanceIdA(devInfoSet, &devInfo, NULL, 0, &sDevIfaceId);

    PSTR pDevIfaceId = calloc(sDevIfaceId, sizeof(CHAR));
    if (!pDevIfaceId)
    {
        fputs("calloc: Out of memory.\n", stderr);
        return 1;
    }

    int ret = get_instance(devInfoSet, &devInfo, pDevIfaceId, sDevIfaceId, pDevIfaceDetail);

    free(pDevIfaceId);
    return ret;
}

int get_instance(HDEVINFO devInfoSet, PSP_DEVINFO_DATA pdevInfo, PSTR pDevIfaceId, DWORD sDevIfaceId, PSP_DEVICE_INTERFACE_DETAIL_DATA_A pDevIfaceDetail)
{
    if (!SetupDiGetDeviceInstanceIdA(devInfoSet, pdevInfo, pDevIfaceId, sDevIfaceId, NULL))
    {
        fprintf(stderr, "SetupDiGetDeviceInstanceIdA: Error %lu\n", GetLastError());
        return 1;
    }

    printf("Device instance id: %s\nDevice path: %s\n", pDevIfaceId, pDevIfaceDetail->DevicePath);
    return 0;
}