improve installer

use standard syntax for service binpath

throw if copy_file fails

5 files changed, 76 insertions, 52 deletions

diff --git a/common/utility-install.hpp b/common/utility-install.hpp
index e1823e4..55ae9d6 100644
--- a/common/utility-install.hpp
+++ b/common/utility-install.hpp
@@ -10,25 +10,24 @@ namespace wr = winreg;
 
 inline const std::wstring DRIVER_NAME = L"rawaccel";
 inline const std::wstring DRIVER_FILE_NAME = DRIVER_NAME + L".sys";
+inline const std::wstring DRIVER_ENV_PATH = L"%systemroot%\\system32\\drivers\\" + DRIVER_FILE_NAME;
 
-fs::path get_sys_path() {
-    std::wstring path;
-    path.resize(MAX_PATH);
+inline const auto sys_error = [](auto what, DWORD code = GetLastError()) {
+    return std::system_error(code, std::system_category(), what);
+};
 
-    UINT chars_copied = GetSystemDirectoryW(path.data(), MAX_PATH);
-    if (chars_copied == 0) throw std::runtime_error("GetSystemDirectory failed");
+inline std::wstring expand(const std::wstring& env_path) {
+    std::wstring path(MAX_PATH, L'\0');
 
-    path.resize(chars_copied);
+    auto len = ExpandEnvironmentStringsW(env_path.c_str(), &path[0], MAX_PATH);
+    if (len == 0) throw sys_error("ExpandEnvironmentStrings failed");
+    path.resize(len - 1);
     return path;
 }
 
-fs::path get_target_path() {
-    return get_sys_path() / L"drivers" / DRIVER_FILE_NAME;
-}
-
-fs::path make_temp_path(const fs::path& p) {
+inline fs::path make_temp_path(const fs::path& p) {
     auto tmp_path = p;
-    tmp_path.concat(".tmp");
+    tmp_path.concat(L".tmp");
     return tmp_path;
 }
 
diff --git a/installer/installer.cpp b/installer/installer.cpp
index cf5a43a..27c9414 100644
--- a/installer/installer.cpp
+++ b/installer/installer.cpp
@@ -3,24 +3,16 @@
 #include <utility-install.hpp>
 #include <VersionHelpers.h>
 
-void add_service(const fs::path& target) {
-    SC_HANDLE schSCManager = OpenSCManager(
-        NULL,                    // local computer
-        NULL,                    // ServicesActive database 
-        SC_MANAGER_ALL_ACCESS    // full access rights 
-    );
-
-    if (schSCManager == NULL) throw std::runtime_error("OpenSCManager failed");
-
-    SC_HANDLE schService = CreateService(
-        schSCManager,              // SCM database 
+void add_service(SC_HANDLE srv_manager) {
+    SC_HANDLE srv = CreateServiceW(
+        srv_manager,               // SCM database 
         DRIVER_NAME.c_str(),       // name of service 
         DRIVER_NAME.c_str(),       // service name to display 
         SERVICE_ALL_ACCESS,        // desired access 
         SERVICE_KERNEL_DRIVER,     // service type 
         SERVICE_DEMAND_START,      // start type 
         SERVICE_ERROR_NORMAL,      // error control type 
-        target.c_str(),            // path to service's binary 
+        DRIVER_ENV_PATH.c_str(),   // path to service's binary 
         NULL,                      // no load ordering group 
         NULL,                      // no tag identifier 
         NULL,                      // no dependencies 
@@ -28,45 +20,76 @@ void add_service(const fs::path& target) {
         NULL                       // no password 
     );
 
-    if (schService) {
-        CloseServiceHandle(schService);
-        CloseServiceHandle(schSCManager);
-        return;
-    }
+    if (srv) CloseServiceHandle(srv);
+    else throw sys_error("CreateService failed");
+}
 
-    if (auto err = GetLastError(); err != ERROR_SERVICE_EXISTS) {
-        CloseServiceHandle(schSCManager);
-        throw std::runtime_error("CreateService failed");
-    }
+BOOL update_service(SC_HANDLE srv) {
+    return ChangeServiceConfigW(
+        srv,                       // service handle 
+        SERVICE_KERNEL_DRIVER,     // service type 
+        SERVICE_DEMAND_START,      // start type 
+        SERVICE_ERROR_NORMAL,      // error control type 
+        DRIVER_ENV_PATH.c_str(),   // path to service's binary 
+        NULL,                      // no load ordering group 
+        NULL,                      // no tag identifier 
+        NULL,                      // no dependencies 
+        NULL,                      // LocalSystem account 
+        NULL,                      // no password
+        DRIVER_NAME.c_str()        // service name to display
+    );
 }
 
 int main() {
+    SC_HANDLE srv_manager = NULL;
+
     try {
         if (!IsWindows10OrGreater()) {
             throw std::runtime_error("OS not supported, you need at least Windows 10");
         }
+
         fs::path source = fs::path(L"driver") / DRIVER_FILE_NAME;
 
         if (!fs::exists(source)) {
             throw std::runtime_error(source.generic_string() + " does not exist");
         }
 
-        fs::path target = get_target_path();
-
+        fs::path target = expand(DRIVER_ENV_PATH);
+        
         if (fs::exists(target)) {
             std::cout << "Driver already installed. Removing previous installation.\n";
-        }
 
-        add_service(target);
+            fs::path tmp = make_temp_path(target);
 
-        fs::path tmp = make_temp_path(target);
+            // schedule tmp to be deleted if rename target -> tmp is successful
+            if (MoveFileExW(target.c_str(), tmp.c_str(), MOVEFILE_REPLACE_EXISTING)) {
+                MoveFileExW(tmp.c_str(), NULL, MOVEFILE_DELAY_UNTIL_REBOOT);
+            }
+        }
 
-        // schedule tmp to be deleted if rename target -> tmp is successful
-        if (MoveFileExW(target.c_str(), tmp.c_str(), MOVEFILE_REPLACE_EXISTING)) {
-            MoveFileExW(tmp.c_str(), NULL, MOVEFILE_DELAY_UNTIL_REBOOT);
+        if (!fs::copy_file(source, target, fs::copy_options::overwrite_existing)) {
+            throw sys_error("copy_file failed");
         }
 
-        fs::copy_file(source, target, fs::copy_options::overwrite_existing);
+        srv_manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
+        if (srv_manager == NULL) throw sys_error("OpenSCManager failed");
+
+        SC_HANDLE srv = OpenServiceW(srv_manager, DRIVER_NAME.c_str(), SC_MANAGER_ALL_ACCESS);
+
+        if (srv != NULL) {
+            BOOL success = update_service(srv);
+            CloseServiceHandle(srv);
+            if (!success) throw sys_error("ChangeServiceConfig failed");
+        }
+        else {
+            auto error_code = GetLastError();
+            if (error_code == ERROR_SERVICE_DOES_NOT_EXIST) {
+                add_service(srv_manager);
+            }
+            else {
+                throw sys_error("OpenService failed", error_code);
+            }
+        }
 
         modify_upper_filters([](std::vector<std::wstring>& filters) {
             auto driver_pos = std::find(filters.begin(), filters.end(), DRIVER_NAME);
@@ -86,6 +109,8 @@ int main() {
         std::cerr << "Error: " << e.what() << '\n';
     }
 
+    if (srv_manager) CloseServiceHandle(srv_manager);
+
     std::cout << "Press any key to close this window . . .\n";
     _getwch();
 }
diff --git a/signed/installer.exe b/signed/installer.exe
index 37a6291..321350b 100644
--- a/signed/installer.exe
+++ b/signed/installer.exe
diff --git a/signed/uninstaller.exe b/signed/uninstaller.exe
index 13bc55c..4dd8788 100644
--- a/signed/uninstaller.exe
+++ b/signed/uninstaller.exe
diff --git a/uninstaller/uninstaller.cpp b/uninstaller/uninstaller.cpp
index bd9c564..3434cb7 100644
--- a/uninstaller/uninstaller.cpp
+++ b/uninstaller/uninstaller.cpp
@@ -14,22 +14,22 @@ int main() {
             }
         });
 
-        fs::path target = get_target_path();
+        fs::path target = expand(DRIVER_ENV_PATH);
         fs::path tmp = make_temp_path(target);
 
-        if (fs::exists(target) || fs::exists(tmp)) {
+        if (fs::exists(target)) {
             reboot_required = true;
-        }
 
-        // schedule tmp to be deleted if rename target -> tmp is successful
-        if (MoveFileExW(target.c_str(), tmp.c_str(), MOVEFILE_REPLACE_EXISTING)) {
-            MoveFileExW(tmp.c_str(), NULL, MOVEFILE_DELAY_UNTIL_REBOOT);
-        }
-        else { // tmp is in use and delete is already scheduled
-            if (fs::exists(target)) fs::remove(target);
+            // schedule tmp to be deleted if rename target -> tmp is successful
+            if (MoveFileExW(target.c_str(), tmp.c_str(), MOVEFILE_REPLACE_EXISTING)) {
+                MoveFileExW(tmp.c_str(), NULL, MOVEFILE_DELAY_UNTIL_REBOOT);
+            }
+            else { // tmp is in use and delete is already scheduled
+                fs::remove(target);
+            }
         }
         
-        if (reboot_required) {
+        if (reboot_required || fs::exists(tmp)) {
             std::cout << "Removal complete, change will take effect after restart.\n";
         }
         else {