config.c

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

/*
 * config.c
 */

/* INCLUDES *****************************************************************/

#include "services.h"

#define NDEBUG
#include <debug.h>

/* FUNCTIONS *****************************************************************/


DWORD
ScmOpenServiceKey(LPWSTR lpServiceName,
                  REGSAM samDesired,
                  PHKEY phKey)
{
    HKEY hServicesKey = NULL;
    DWORD dwError;

    *phKey = NULL;

    dwError = RegOpenKeyExW(HKEY_LOCAL_MACHINE,
                            L"System\\CurrentControlSet\\Services",
                            0,
                            KEY_READ,
                            &hServicesKey);
    if (dwError != ERROR_SUCCESS)
        return dwError;

    dwError = RegOpenKeyExW(hServicesKey,
                            lpServiceName,
                            0,
                            samDesired,
                            phKey);

    RegCloseKey(hServicesKey);

    return dwError;
}


DWORD
ScmCreateServiceKey(LPWSTR lpServiceName,
                    REGSAM samDesired,
                    PHKEY phKey)
{
    HKEY hServicesKey = NULL;
    DWORD dwDisposition;
    DWORD dwError;

    *phKey = NULL;

    dwError = RegOpenKeyExW(HKEY_LOCAL_MACHINE,
                            L"System\\CurrentControlSet\\Services",
                            0,
                            KEY_READ | KEY_CREATE_SUB_KEY,
                            &hServicesKey);
    if (dwError != ERROR_SUCCESS)
        return dwError;

    dwError = RegCreateKeyExW(hServicesKey,
                              lpServiceName,
                              0,
                              NULL,
                              REG_OPTION_NON_VOLATILE,
                              samDesired,
                              NULL,
                              phKey,
                              &dwDisposition);
#if 0
    if ((dwError == ERROR_SUCCESS) &&
        (dwDisposition == REG_OPENED_EXISTING_KEY))
    {
        RegCloseKey(*phKey);
        *phKey = NULL;
        dwError = ERROR_SERVICE_EXISTS;
    }
#endif

    RegCloseKey(hServicesKey);

    return dwError;
}



DWORD
ScmWriteDependencies(HKEY hServiceKey,
                     LPWSTR lpDependencies,
                     DWORD dwDependenciesLength)
{
    DWORD dwError = ERROR_SUCCESS;
    DWORD dwGroupLength = 0;
    DWORD dwServiceLength = 0;
    DWORD dwLength;
    LPWSTR lpGroupDeps;
    LPWSTR lpServiceDeps;
    LPWSTR lpSrc;
    LPWSTR lpDst;

    if (*lpDependencies == 0)
    {
        RegDeleteValue(hServiceKey,
                       L"DependOnService");
        RegDeleteValue(hServiceKey,
                       L"DependOnGroup");
    }
    else
    {
        lpGroupDeps = HeapAlloc(GetProcessHeap(),
                                HEAP_ZERO_MEMORY,
                                (dwDependenciesLength + 2) * sizeof(WCHAR));
        if (lpGroupDeps == NULL)
            return ERROR_NOT_ENOUGH_MEMORY;

        lpSrc = lpDependencies;
        lpDst = lpGroupDeps;
        while (*lpSrc != 0)
        {
            dwLength = wcslen(lpSrc);
            if (*lpSrc == SC_GROUP_IDENTIFIERW)
            {
                lpSrc++;
                dwGroupLength += dwLength;
                wcscpy(lpDst, lpSrc);
                lpDst = lpDst + dwLength;
            }

            lpSrc = lpSrc + dwLength;
        }
        *lpDst = 0;
        lpDst++;
        dwGroupLength++;

        lpSrc = lpDependencies;
        lpServiceDeps = lpDst;
        while (*lpSrc != 0)
        {
            dwLength = wcslen(lpSrc) + 1;
            if (*lpSrc != SC_GROUP_IDENTIFIERW)
            {
                dwServiceLength += dwLength;
                wcscpy(lpDst, lpSrc);
                lpDst = lpDst + dwLength;
            }

            lpSrc = lpSrc + dwLength;
        }
        *lpDst = 0;
        dwServiceLength++;

        dwError = RegSetValueExW(hServiceKey,
                                 L"DependOnGroup",
                                 0,
                                 REG_MULTI_SZ,
                                 (LPBYTE)lpGroupDeps,
                                 dwGroupLength * sizeof(WCHAR));

        if (dwError == ERROR_SUCCESS)
        {
            dwError = RegSetValueExW(hServiceKey,
                                     L"DependOnService",
                                     0,
                                     REG_MULTI_SZ,
                                     (LPBYTE)lpServiceDeps,
                                     dwServiceLength * sizeof(WCHAR));
        }

        HeapFree(GetProcessHeap(), 0, lpGroupDeps);
    }

    return dwError;
}


DWORD
ScmMarkServiceForDelete(PSERVICE pService)
{
    HKEY hServiceKey = NULL;
    DWORD dwValue = 1;
    DWORD dwError;

    DPRINT("ScmMarkServiceForDelete() called\n");

    dwError = ScmOpenServiceKey(pService->lpServiceName,
                                KEY_WRITE,
                                &hServiceKey);
    if (dwError != ERROR_SUCCESS)
        return dwError;

    dwError = RegSetValueExW(hServiceKey,
                             L"DeleteFlag",
                             0,
                             REG_DWORD,
                             (LPBYTE)&dwValue,
                             sizeof(DWORD));

    RegCloseKey(hServiceKey);

    return dwError;
}


BOOL
ScmIsDeleteFlagSet(HKEY hServiceKey)
{
    DWORD dwError;
    DWORD dwType;
    DWORD dwFlag;
    DWORD dwSize = sizeof(DWORD);

    dwError = RegQueryValueExW(hServiceKey,
                               L"DeleteFlag",
                               0,
                               &dwType,
                               (LPBYTE)&dwFlag,
                               &dwSize);

    return (dwError == ERROR_SUCCESS);
}


DWORD
ScmReadString(HKEY hServiceKey,
              LPWSTR lpValueName,
              LPWSTR *lpValue)
{
    DWORD dwError;
    DWORD dwSize;
    DWORD dwType;
    DWORD dwSizeNeeded;
    LPWSTR expanded = NULL;
    LPWSTR ptr = NULL;

    *lpValue = NULL;

    dwSize = 0;
    dwError = RegQueryValueExW(hServiceKey,
                               lpValueName,
                               0,
                               &dwType,
                               NULL,
                               &dwSize);
    if (dwError != ERROR_SUCCESS)
        return dwError;

    ptr = HeapAlloc(GetProcessHeap(), 0, dwSize);
    if (ptr == NULL)
        return ERROR_NOT_ENOUGH_MEMORY;

    dwError = RegQueryValueExW(hServiceKey,
                               lpValueName,
                               0,
                               &dwType,
                               (LPBYTE)ptr,
                               &dwSize);
    if (dwError != ERROR_SUCCESS)
        goto done;

    if (dwType == REG_EXPAND_SZ)
    {
        /* Expand the value... */
        dwSizeNeeded = ExpandEnvironmentStringsW((LPCWSTR)ptr, NULL, 0);
        if (dwSizeNeeded == 0)
        {
            dwError = GetLastError();
            goto done;
        }
        expanded = HeapAlloc(GetProcessHeap(), 0, dwSizeNeeded * sizeof(WCHAR));
        if (dwSizeNeeded < ExpandEnvironmentStringsW((LPCWSTR)ptr, expanded, dwSizeNeeded))
        {
            dwError = GetLastError();
            goto done;
        }
        *lpValue = expanded;
        HeapFree(GetProcessHeap(), 0, ptr);
        dwError = ERROR_SUCCESS;
    }
    else
    {
        *lpValue = ptr;
    }

done:;
    if (dwError != ERROR_SUCCESS)
    {
        HeapFree(GetProcessHeap(), 0, ptr);
        HeapFree(GetProcessHeap(), 0, expanded);
    }

    return dwError;
}

/* EOF */