/*
* Source file for missing WinCE functionality
* Copyright © 2012 RealVNC Ltd.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "missing.h"
#include <config.h>
#include <libusbi.h>
#include <windows.h>
// The registry path to store environment variables
#define ENVIRONMENT_REG_PATH _T("Software\\libusb\\environment")
/* Workaround getenv not being available on WinCE.
* Instead look in HKLM\Software\libusb\environment */
char *getenv(const char *name)
{
static char value[MAX_PATH];
TCHAR wValue[MAX_PATH];
WCHAR wName[MAX_PATH];
DWORD dwType, dwData;
HKEY hkey;
LONG rc;
if (!name)
return NULL;
if (MultiByteToWideChar(CP_UTF8, 0, name, -1, wName, MAX_PATH) <= 0) {
usbi_dbg("Failed to convert environment variable name to wide string");
return NULL;
}
wName[MAX_PATH - 1] = 0; // Be sure it's NUL terminated
rc = RegOpenKeyEx(HKEY_LOCAL_MACHINE, ENVIRONMENT_REG_PATH, 0, KEY_QUERY_VALUE, &hkey);
if (rc != ERROR_SUCCESS) {
usbi_dbg("Failed to open registry key for getenv with error %d", rc);
return NULL;
}
// Attempt to read the key
dwData = sizeof(wValue);
rc = RegQueryValueEx(hkey, wName, NULL, &dwType,
(LPBYTE)&wValue, &dwData);
RegCloseKey(hkey);
if (rc != ERROR_SUCCESS) {
usbi_dbg("Failed to read registry key value for getenv with error %d", rc);
return NULL;
}
if (dwType != REG_SZ) {
usbi_dbg("Registry value was of type %d instead of REG_SZ", dwType);
return NULL;
}
// Success in reading the key, convert from WCHAR to char
if (WideCharToMultiByte(CP_UTF8, 0,
wValue, dwData / sizeof(*wValue),
value, MAX_PATH,
NULL, NULL) <= 0) {
usbi_dbg("Failed to convert environment variable value to narrow string");
return NULL;
}
value[MAX_PATH - 1] = 0; // Be sure it's NUL terminated
return value;
}