| 1 | //go:build windows && native_webview2loader |
| 2 | |
| 3 | package webviewloader |
| 4 | |
| 5 | import ( |
| 6 | "errors" |
| 7 | "fmt" |
| 8 | "os" |
| 9 | "sync" |
| 10 | "unsafe" |
| 11 | |
| 12 | "github.com/jchv/go-winloader" |
| 13 | |
| 14 | "golang.org/x/sys/windows" |
| 15 | ) |
| 16 | |
| 17 | func init() { |
| 18 | preventEnvAndRegistryOverrides(nil, nil, "") |
| 19 | } |
| 20 | |
| 21 | var ( |
| 22 | memOnce sync.Once |
| 23 | memModule winloader.Module |
| 24 | memCreate winloader.Proc |
| 25 | memCompareBrowserVersions winloader.Proc |
| 26 | memGetAvailableCoreWebView2BrowserVersionString winloader.Proc |
| 27 | memErr error |
| 28 | ) |
| 29 | |
| 30 | const ( |
| 31 | // https://referencesource.microsoft.com/#system.web/Util/hresults.cs,20 |
| 32 | E_FILENOTFOUND = 0x80070002 |
| 33 | ) |
| 34 | |
| 35 | // CompareBrowserVersions will compare the 2 given versions and return: |
| 36 | // |
| 37 | // Less than zero: v1 < v2 |
| 38 | // zero: v1 == v2 |
| 39 | // Greater than zero: v1 > v2 |
| 40 | func CompareBrowserVersions(v1 string, v2 string) (int, error) { |
| 41 | _v1, err := windows.UTF16PtrFromString(v1) |
| 42 | if err != nil { |
| 43 | return 0, err |
| 44 | } |
| 45 | _v2, err := windows.UTF16PtrFromString(v2) |
| 46 | if err != nil { |
| 47 | return 0, err |
| 48 | } |
| 49 | |
| 50 | err = loadFromMemory() |
| 51 | if err != nil { |
| 52 | return 0, err |
| 53 | } |
| 54 | |
| 55 | var result int32 |
| 56 | _, _, err = memCompareBrowserVersions.Call( |
| 57 | uint64(uintptr(unsafe.Pointer(_v1))), |
| 58 | uint64(uintptr(unsafe.Pointer(_v2))), |
| 59 | uint64(uintptr(unsafe.Pointer(&result)))) |
| 60 | |
| 61 | if err != windows.ERROR_SUCCESS { |
| 62 | return 0, err |
| 63 | } |
| 64 | return int(result), nil |
| 65 | } |
| 66 | |
| 67 | // GetAvailableCoreWebView2BrowserVersionString returns version of the webview2 runtime. |
| 68 | // If path is empty, it will try to find installed webview2 is the system. |
| 69 | // If there is no version installed, a blank string is returned. |
| 70 | func GetAvailableCoreWebView2BrowserVersionString(path string) (string, error) { |
| 71 | if path != "" { |
| 72 | // The default implementation fails if CGO and a fixed browser path is used. It's caused by the go-winloader |
| 73 | // which loads the native DLL from memory. |
| 74 | // Use the new GoWebView2Loader in this case, in the future we will make GoWebView2Loader |
| 75 | // feature-complete and remove the use of the native DLL and go-winloader. |
| 76 | version, err := goGetAvailableCoreWebView2BrowserVersionString(path) |
| 77 | if errors.Is(err, errNoClientDLLFound) { |
| 78 | // WebView2 is not found |
| 79 | return "", nil |
| 80 | } else if err != nil { |
| 81 | return "", err |
| 82 | } |
| 83 | |
| 84 | return version, nil |
| 85 | } |
| 86 | |
| 87 | err := loadFromMemory() |
| 88 | if err != nil { |
| 89 | return "", err |
| 90 | } |
| 91 | |
| 92 | var browserPath *uint16 = nil |
| 93 | if path != "" { |
| 94 | browserPath, err = windows.UTF16PtrFromString(path) |
| 95 | if err != nil { |
| 96 | return "", fmt.Errorf("error calling UTF16PtrFromString for %s: %v", path, err) |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | preventEnvAndRegistryOverrides(browserPath, nil, "") |
| 101 | var result *uint16 |
| 102 | res, _, err := memGetAvailableCoreWebView2BrowserVersionString.Call( |
| 103 | uint64(uintptr(unsafe.Pointer(browserPath))), |
| 104 | uint64(uintptr(unsafe.Pointer(&result)))) |
| 105 | |
| 106 | if res != 0 { |
| 107 | if res == E_FILENOTFOUND { |
| 108 | // WebView2 is not installed |
| 109 | return "", nil |
| 110 | } |
| 111 | |
| 112 | return "", fmt.Errorf("Unable to call GetAvailableCoreWebView2BrowserVersionString (%x): %w", res, err) |
| 113 | } |
| 114 | |
| 115 | version := windows.UTF16PtrToString(result) |
| 116 | windows.CoTaskMemFree(unsafe.Pointer(result)) |
| 117 | return version, nil |
| 118 | } |
| 119 | |
| 120 | // CreateCoreWebView2EnvironmentWithOptions tries to load WebviewLoader2 and |
| 121 | // call the CreateCoreWebView2EnvironmentWithOptions routine. |
| 122 | func CreateCoreWebView2EnvironmentWithOptions(browserExecutableFolder, userDataFolder *uint16, environmentCompletedHandle uintptr, additionalBrowserArgs string) (uintptr, error) { |
| 123 | err := loadFromMemory() |
| 124 | if err != nil { |
| 125 | return 0, err |
| 126 | } |
| 127 | |
| 128 | preventEnvAndRegistryOverrides(browserExecutableFolder, userDataFolder, additionalBrowserArgs) |
| 129 | res, _, _ := memCreate.Call( |
| 130 | uint64(uintptr(unsafe.Pointer(browserExecutableFolder))), |
| 131 | uint64(uintptr(unsafe.Pointer(userDataFolder))), |
| 132 | 0, |
| 133 | uint64(environmentCompletedHandle), |
| 134 | ) |
| 135 | return uintptr(res), nil |
| 136 | } |
| 137 | |
| 138 | func loadFromMemory() error { |
| 139 | var err error |
| 140 | // DLL is not available natively. Try loading embedded copy. |
| 141 | memOnce.Do(func() { |
| 142 | memModule, memErr = winloader.LoadFromMemory(WebView2Loader) |
| 143 | if memErr != nil { |
| 144 | err = fmt.Errorf("Unable to load WebView2Loader.dll from memory: %w", memErr) |
| 145 | return |
| 146 | } |
| 147 | memCreate = memModule.Proc("CreateCoreWebView2EnvironmentWithOptions") |
| 148 | memCompareBrowserVersions = memModule.Proc("CompareBrowserVersions") |
| 149 | memGetAvailableCoreWebView2BrowserVersionString = memModule.Proc("GetAvailableCoreWebView2BrowserVersionString") |
| 150 | }) |
| 151 | return err |
| 152 | } |
| 153 | |
| 154 | func preventEnvAndRegistryOverrides(browserFolder, userDataFolder *uint16, additionalBrowserArgs string) { |
| 155 | // Setting these env variables to empty string also prevents registry overrides because webview2loader |
| 156 | // checks for existence and not for empty value |
| 157 | os.Setenv("WEBVIEW2_PIPE_FOR_SCRIPT_DEBUGGER", "") |
| 158 | |
| 159 | // Set these overrides to the values or empty to prevent registry and external env overrides |
| 160 | os.Setenv("WEBVIEW2_ADDITIONAL_BROWSER_ARGUMENTS", additionalBrowserArgs) |
| 161 | os.Setenv("WEBVIEW2_RELEASE_CHANNEL_PREFERENCE", "0") |
| 162 | os.Setenv("WEBVIEW2_BROWSER_EXECUTABLE_FOLDER", windows.UTF16PtrToString(browserFolder)) |
| 163 | os.Setenv("WEBVIEW2_USER_DATA_FOLDER", windows.UTF16PtrToString(userDataFolder)) |
| 164 | } |
| 165 | |
| 166 | func goGetAvailableCoreWebView2BrowserVersionString(browserExecutableFolder string) (string, error) { |
| 167 | clientPath, err := findEmbeddedClientDll(browserExecutableFolder) |
| 168 | if err != nil { |
| 169 | return "", err |
| 170 | } |
| 171 | |
| 172 | return findEmbeddedBrowserVersion(clientPath) |
| 173 | } |
| 174 |