quick and dirty delta package extractor using dpx.dll

dpexpand.cpp

#define UNICODE 1

#include <windows.h>
#include <stdio.h>
#include <shellapi.h>
#include <dpx.h>
#include <malloc.h>

using namespace std;

void print_usage(LPWSTR exename) {
	wprintf(L"usage:\n");
	wprintf(L"%s package [destination]\n", exename);
}

int __cdecl main()
{
	LPWSTR *argv;
	int argc;

	argv = CommandLineToArgvW(GetCommandLineW(), &argc);

	if ((argv == NULL) || (argc < 1)) {
		wprintf(L"internal error\n");
		return -1;
	} else if (argc == 1) {
		print_usage(argv[0]);
		return -1;
	}

	LPWSTR cabPathAsPassed = argv[1];
	DWORD cabPathLen = GetFullPathNameW(cabPathAsPassed, 0, NULL, NULL);
	LPWSTR cabPath = static_cast<LPWSTR>(_malloca(cabPathLen * sizeof(WCHAR)));
	GetFullPathNameW(cabPathAsPassed, cabPathLen, cabPath, NULL);

	DWORD exPathLen;
	LPWSTR exPath;

	if (argc > 2) {
		LPWSTR exPathAsPassed = argv[2];
		exPathLen = GetFullPathNameW(exPathAsPassed, 0, NULL, NULL);
		exPath = static_cast<LPWSTR>(_malloca(exPathLen * sizeof(WCHAR)));
		GetFullPathNameW(exPathAsPassed, exPathLen, exPath, NULL);
	} else {
		exPathLen = GetCurrentDirectoryW(0, NULL);
		exPath = static_cast<LPWSTR>(_malloca(exPathLen * sizeof(WCHAR)));
		GetCurrentDirectoryW(exPathLen, exPath);
	}

	wprintf(L"Extracting %s\n", cabPath);
	wprintf(L"        to %s\n", exPath);

	IDpxJob *dpxJob = NULL;
	DpxNewJob(exPath, &dpxJob);

	IDpxContainer *cab = NULL;
	dpxJob->AddContainer(cabPath, &cab);

	cab->ExtractAllFiles();
	dpxJob->Resume(DPX_RESUME_AND_DOWNLOAD);

	return 0;
}