| 1 | //go:build windows |
| 2 | |
| 3 | package webviewloader |
| 4 | |
| 5 | import ( |
| 6 | "fmt" |
| 7 | "syscall" |
| 8 | "unicode/utf16" |
| 9 | "unsafe" |
| 10 | |
| 11 | "golang.org/x/sys/windows" |
| 12 | ) |
| 13 | |
| 14 | var ( |
| 15 | modkernel32 = windows.NewLazySystemDLL("kernel32.dll") |
| 16 | procGlobalAlloc = modkernel32.NewProc("GlobalAlloc") |
| 17 | procGlobalFree = modkernel32.NewProc("GlobalFree") |
| 18 | |
| 19 | modversion = windows.NewLazySystemDLL("version.dll") |
| 20 | procGetFileVersionInfoSize = modversion.NewProc("GetFileVersionInfoSizeW") |
| 21 | procGetFileVersionInfo = modversion.NewProc("GetFileVersionInfoW") |
| 22 | procVerQueryValue = modversion.NewProc("VerQueryValueW") |
| 23 | |
| 24 | modole32 = windows.NewLazySystemDLL("ole32.dll") |
| 25 | procCoTaskMemAlloc = modole32.NewProc("CoTaskMemAlloc") |
| 26 | ) |
| 27 | |
| 28 | func getFileVersionInfo(path string) ([]byte, error) { |
| 29 | lptstrFilename, err := syscall.UTF16PtrFromString(path) |
| 30 | if err != nil { |
| 31 | return nil, err |
| 32 | } |
| 33 | |
| 34 | size, _, err := procGetFileVersionInfoSize.Call( |
| 35 | uintptr(unsafe.Pointer(lptstrFilename)), |
| 36 | 0, |
| 37 | ) |
| 38 | |
| 39 | err = maskErrorSuccess(err) |
| 40 | if size == 0 && err == nil { |
| 41 | err = fmt.Errorf("GetFileVersionInfoSize failed") |
| 42 | } |
| 43 | |
| 44 | if err != nil { |
| 45 | return nil, err |
| 46 | } |
| 47 | |
| 48 | data := make([]byte, size) |
| 49 | ret, _, err := procGetFileVersionInfo.Call( |
| 50 | uintptr(unsafe.Pointer(lptstrFilename)), |
| 51 | 0, |
| 52 | uintptr(size), |
| 53 | uintptr(unsafe.Pointer(&data[0])), |
| 54 | ) |
| 55 | |
| 56 | err = maskErrorSuccess(err) |
| 57 | if ret == 0 && err == nil { |
| 58 | err = fmt.Errorf("GetFileVersionInfo failed") |
| 59 | } |
| 60 | |
| 61 | if err != nil { |
| 62 | return nil, err |
| 63 | } |
| 64 | return data, nil |
| 65 | } |
| 66 | |
| 67 | func verQueryValueString(block []byte, subBlock string) (string, error) { |
| 68 | // Allocate memory from native side to make sure the block doesn't get moved |
| 69 | // because we get a pointer into that memory block from the native verQueryValue |
| 70 | // call back. |
| 71 | pBlock := globalAlloc(0, uint32(len(block))) |
| 72 | defer globalFree(unsafe.Pointer(pBlock)) |
| 73 | |
| 74 | // Copy the memory region into native side memory |
| 75 | copy(unsafe.Slice((*byte)(pBlock), len(block)), block) |
| 76 | |
| 77 | lpSubBlock, err := syscall.UTF16PtrFromString(subBlock) |
| 78 | if err != nil { |
| 79 | return "", err |
| 80 | } |
| 81 | |
| 82 | var lplpBuffer unsafe.Pointer |
| 83 | var puLen uint |
| 84 | ret, _, err := procVerQueryValue.Call( |
| 85 | uintptr(pBlock), |
| 86 | uintptr(unsafe.Pointer(lpSubBlock)), |
| 87 | uintptr(unsafe.Pointer(&lplpBuffer)), |
| 88 | uintptr(unsafe.Pointer(&puLen)), |
| 89 | ) |
| 90 | |
| 91 | err = maskErrorSuccess(err) |
| 92 | if ret == 0 && err == nil { |
| 93 | err = fmt.Errorf("VerQueryValue failed") |
| 94 | } |
| 95 | |
| 96 | if err != nil { |
| 97 | return "", err |
| 98 | } |
| 99 | |
| 100 | if puLen <= 1 { |
| 101 | return "", nil |
| 102 | } |
| 103 | puLen -= 1 // Remove Null-Terminator |
| 104 | |
| 105 | wchar := unsafe.Slice((*uint16)(lplpBuffer), puLen) |
| 106 | return string(utf16.Decode(wchar)), nil |
| 107 | } |
| 108 | |
| 109 | func globalAlloc(uFlags uint, dwBytes uint32) unsafe.Pointer { |
| 110 | ret, _, _ := procGlobalAlloc.Call( |
| 111 | uintptr(uFlags), |
| 112 | uintptr(dwBytes)) |
| 113 | |
| 114 | if ret == 0 { |
| 115 | panic("globalAlloc failed") |
| 116 | } |
| 117 | |
| 118 | return unsafe.Pointer(ret) |
| 119 | } |
| 120 | |
| 121 | func globalFree(data unsafe.Pointer) { |
| 122 | ret, _, _ := procGlobalFree.Call(uintptr(data)) |
| 123 | if ret != 0 { |
| 124 | panic("globalFree failed") |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | func maskErrorSuccess(err error) error { |
| 129 | if err == windows.ERROR_SUCCESS { |
| 130 | return nil |
| 131 | } |
| 132 | return err |
| 133 | } |
| 134 | |
| 135 | func coTaskMemAlloc(size int) unsafe.Pointer { |
| 136 | ret, _, _ := procCoTaskMemAlloc.Call( |
| 137 | uintptr(size)) |
| 138 | |
| 139 | if ret == 0 { |
| 140 | panic("coTaskMemAlloc failed") |
| 141 | } |
| 142 | return unsafe.Pointer(ret) |
| 143 | } |
| 144 |