windows-nt/Source/XPSP1/NT/windows/appcompat/shims/general/searchpathinapppaths.cpp
2020-09-26 16:20:57 +08:00

171 lines
4.7 KiB
C++

/*++
Copyright (c) 2000 Microsoft Corporation
Module Name:
SearchPathInAppPaths.cpp
Abstract:
An application might use SearchPath to determine if a specific EXE is found
in the current path. Some applications have registered their path with the
shell in "HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths"
If SearchPath fails, we'll check to see if the applications has registered a path.
History:
03/03/2000 robkenny Created
--*/
#include "precomp.h"
#include <stdio.h>
IMPLEMENT_SHIM_BEGIN(SearchPathInAppPaths)
#include "ShimHookMacro.h"
APIHOOK_ENUM_BEGIN
APIHOOK_ENUM_ENTRY(SearchPathA)
APIHOOK_ENUM_END
/*++
Grab an entry from the registry, expand if REG_EXPAND_SZ.
Return a full path in lpBuffer, and a pointer to the file part.
Return the number of chars copied into lpBuffer, including NULL terminator.
--*/
DWORD
GetPathFromRegistryA(
HKEY hKey, // handle to key
LPCSTR lpKeyPath, // value name
LPCSTR lpValueName, // value name
DWORD nBufferLength, // size of buffer
LPSTR lpBuffer, // found file name buffer
LPSTR *lpFilePart // file component (optional)
)
{
DWORD returnValue = 0;
HKEY hkPathKey;
LONG success;
success = RegOpenKeyExA(hKey, lpKeyPath, 0, KEY_QUERY_VALUE, &hkPathKey);
if (success == ERROR_SUCCESS)
{
DWORD appPathsKeyType;
char appPathsData[MAX_PATH];
DWORD appPathsDataSize = MAX_PATH;
appPathsData[0] = 0;
success = RegQueryValueExA(
hkPathKey, lpValueName, NULL, &appPathsKeyType, (BYTE *)appPathsData,
&appPathsDataSize);
if (success == ERROR_SUCCESS)
{
if (appPathsKeyType == REG_EXPAND_SZ)
{
// Gotta expand the env. vars
char expandedAppPathsData[MAX_PATH];
DWORD dwChars = ExpandEnvironmentStringsA(appPathsData, expandedAppPathsData, MAX_PATH);
if (dwChars > 0)
{
returnValue = GetFullPathNameA(expandedAppPathsData, nBufferLength, lpBuffer, lpFilePart);
}
}
else if (appPathsKeyType == REG_SZ)
{
returnValue = GetFullPathNameA(appPathsData, nBufferLength, lpBuffer, lpFilePart);
}
}
RegCloseKey(hkPathKey);
}
return returnValue;
}
DWORD
APIHOOK(SearchPathA)(
LPCSTR lpPath, // search path
LPCSTR lpFileName, // file name
LPCSTR lpExtension, // file extension
DWORD nBufferLength, // size of buffer
LPSTR lpBuffer, // found file name buffer
LPSTR *lpFilePart // file component
)
{
DWORD returnValue = ORIGINAL_API(SearchPathA)(
lpPath, lpFileName, lpExtension, nBufferLength, lpBuffer, lpFilePart);
if (returnValue == 0)
{
// Search failed, look in the registry.
// First look for lpFileName. If that fails, append lpExtension and look again.
CSTRING_TRY
{
CString csFile(lpFileName);
CString csReg(L"Software\\Microsoft\\Windows\\CurrentVersion\\App Paths\\");
csReg.AppendPath(csFile);
DWORD success;
success = GetPathFromRegistryA(HKEY_LOCAL_MACHINE,
csReg.GetAnsi(),
NULL, // (Default) entry
nBufferLength,
lpBuffer,
lpFilePart);
if (success > 0)
{
// SearchPath returns the number of chars, not including the NULL terminator
returnValue = success - 1;
}
else
{
// Try appending the extension onto the path
CString csExt(lpExtension);
csReg += csExt;
success = GetPathFromRegistryA(HKEY_LOCAL_MACHINE,
csReg.GetAnsi(),
NULL, // (Default) entry
nBufferLength,
lpBuffer,
lpFilePart);
if (success > 0)
{
// SearchPath returns the number of chars, not including the NULL terminator
returnValue = success - 1;
}
}
}
CSTRING_CATCH
{
// Do nothing
}
}
return returnValue;
}
/*++
Register hooked functions
--*/
HOOK_BEGIN
APIHOOK_ENTRY(KERNEL32.DLL, SearchPathA)
HOOK_END
IMPLEMENT_SHIM_END