rum-goggles/vendor/github.com/wailsapp/go-webview2/webviewloader/syscall.go
2024-02-23 11:39:16 -05:00

144 lines
3.1 KiB
Go

//go:build windows
package webviewloader
import (
"fmt"
"syscall"
"unicode/utf16"
"unsafe"
"golang.org/x/sys/windows"
)
var (
modkernel32 = windows.NewLazySystemDLL("kernel32.dll")
procGlobalAlloc = modkernel32.NewProc("GlobalAlloc")
procGlobalFree = modkernel32.NewProc("GlobalFree")
modversion = windows.NewLazySystemDLL("version.dll")
procGetFileVersionInfoSize = modversion.NewProc("GetFileVersionInfoSizeW")
procGetFileVersionInfo = modversion.NewProc("GetFileVersionInfoW")
procVerQueryValue = modversion.NewProc("VerQueryValueW")
modole32 = windows.NewLazySystemDLL("ole32.dll")
procCoTaskMemAlloc = modole32.NewProc("CoTaskMemAlloc")
)
func getFileVersionInfo(path string) ([]byte, error) {
lptstrFilename, err := syscall.UTF16PtrFromString(path)
if err != nil {
return nil, err
}
size, _, err := procGetFileVersionInfoSize.Call(
uintptr(unsafe.Pointer(lptstrFilename)),
0,
)
err = maskErrorSuccess(err)
if size == 0 && err == nil {
err = fmt.Errorf("GetFileVersionInfoSize failed")
}
if err != nil {
return nil, err
}
data := make([]byte, size)
ret, _, err := procGetFileVersionInfo.Call(
uintptr(unsafe.Pointer(lptstrFilename)),
0,
uintptr(size),
uintptr(unsafe.Pointer(&data[0])),
)
err = maskErrorSuccess(err)
if ret == 0 && err == nil {
err = fmt.Errorf("GetFileVersionInfo failed")
}
if err != nil {
return nil, err
}
return data, nil
}
func verQueryValueString(block []byte, subBlock string) (string, error) {
// Allocate memory from native side to make sure the block doesn't get moved
// because we get a pointer into that memory block from the native verQueryValue
// call back.
pBlock := globalAlloc(0, uint32(len(block)))
defer globalFree(unsafe.Pointer(pBlock))
// Copy the memory region into native side memory
copy(unsafe.Slice((*byte)(pBlock), len(block)), block)
lpSubBlock, err := syscall.UTF16PtrFromString(subBlock)
if err != nil {
return "", err
}
var lplpBuffer unsafe.Pointer
var puLen uint
ret, _, err := procVerQueryValue.Call(
uintptr(pBlock),
uintptr(unsafe.Pointer(lpSubBlock)),
uintptr(unsafe.Pointer(&lplpBuffer)),
uintptr(unsafe.Pointer(&puLen)),
)
err = maskErrorSuccess(err)
if ret == 0 && err == nil {
err = fmt.Errorf("VerQueryValue failed")
}
if err != nil {
return "", err
}
if puLen <= 1 {
return "", nil
}
puLen -= 1 // Remove Null-Terminator
wchar := unsafe.Slice((*uint16)(lplpBuffer), puLen)
return string(utf16.Decode(wchar)), nil
}
func globalAlloc(uFlags uint, dwBytes uint32) unsafe.Pointer {
ret, _, _ := procGlobalAlloc.Call(
uintptr(uFlags),
uintptr(dwBytes))
if ret == 0 {
panic("globalAlloc failed")
}
return unsafe.Pointer(ret)
}
func globalFree(data unsafe.Pointer) {
ret, _, _ := procGlobalFree.Call(uintptr(data))
if ret != 0 {
panic("globalFree failed")
}
}
func maskErrorSuccess(err error) error {
if err == windows.ERROR_SUCCESS {
return nil
}
return err
}
func coTaskMemAlloc(size int) unsafe.Pointer {
ret, _, _ := procCoTaskMemAlloc.Call(
uintptr(size))
if ret == 0 {
panic("coTaskMemAlloc failed")
}
return unsafe.Pointer(ret)
}