Raygui -Access violation crash in GuiTextBox on Windows - Exception 0xc0000005

[janicaleksander]

Application crashes with access violation when calling gui.TextBox() from raylib-go/raygui on Windows.

Exception 0xc0000005 0x0 0xc001b94000 0x7bed93
PC=0x7bed93
signal arrived during external code execution

github.com/gen2brain/raylib-go/raygui._Cfunc_GuiTextBox({0x44070000, 0x43b40000, 0x43480000, 0x42700000}, 0xc001b93ff8, 0x40, 0x0)
_cgo_gotypes.go:835 +0x50
github.com/gen2brain/raylib-go/raygui.TextBox({0x0?, 0x0?, 0xecd400?, 0x0?}, 0xc0001feab0, 0x40, 0x0)
C:/Users/Aleksander/go/pkg/mod/github.com/gen2brain/raylib-go/raygui@v0.0.0-20250617194346-eddd038123ee/raygui.go:980 +0x158

gui.TextBox(bounds, &textString, 64, true)

Issue:
The crash occurs consistently when calling gui.TextBox(). This appears to be a CGO-related issue where the Go garbage collector may be moving string memory while C code is accessing it, causing an invalid memory access.

Expected Behavior:
TextBox should render without crashing.

Actual Behavior:
Application terminates with access violation exception.

[JupiterRider]

Hey @janicaleksander ,

can you please share a code snippet or example to reproduce the error?

[janicaleksander]

w.createUserScene.emailInput = InputField{ bounds: rl.NewRectangle( float32(w.width/2)-100, float32(w.height/2-300), 200, 60, ), text: "", focus: false, textSize: 64, }

gui.TextBox(w.createUserScene.emailInput.bounds, &w.createUserScene.emailInput.text, w.createUserScene.emailInput.textSize, w.createUserScene.emailInput.focus)

This is the tricky part, because this error occurred twice in a row, and then I tried to do it again and this time it didn't happen.

[gen2brain]

@janicaleksander, Occasional crashes suggest you are doing more in your code than what is shown. You are not using Go routines, are you?
If not, as you mentioned, it's possible that GC is cleaning your objects, but from the C side, they're still needed. You can test that by simply adding runtime.KeepAlive(yourobject) at the end, or after the part where it is crashing, to force GC not to clean it.
Edit: Or just try with GOGC=off.

[janicaleksander]

package Application

import (
	gui "github.com/gen2brain/raylib-go/raygui"
	rl "github.com/gen2brain/raylib-go/raylib"
	"github.com/janicaleksander/bcs/Proto"
	"github.com/janicaleksander/bcs/User"
	"strconv"
)

type CreateUserScene struct {
	emailInput      InputField
	passwordInput   InputField
	rePasswordInput InputField
	ruleLevelInput  InputField
	nameInput       InputField
	surnameInput    InputField
	isError         bool
	errorMessage    string
	acceptButton    Button

	isAccept      bool
	acceptMessage string
	//maybe sobe checkbox
}

func (s *CreateUserScene) Reset() {
	s.isError = false
	s.errorMessage = ""

	s.isAccept = false
	s.acceptMessage = ""
}

func (w *Window) createUserSceneSetup() {
	w.createUserScene.Reset()
	w.createUserScene.emailInput = InputField{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2-300),
			200,
			60,
		),
		text:     "",
		focus:    false,
		textSize: 64,
	}
	w.createUserScene.passwordInput = InputField{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2)-200,
			200,
			60),
		text:     "",
		focus:    false,
		textSize: 64,
	}
	w.createUserScene.rePasswordInput = InputField{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2)-100,
			200,
			60),
		text:     "",
		focus:    false,
		textSize: 64,
	}
	w.createUserScene.ruleLevelInput = InputField{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2),
			200,
			60,
		),
		text:     "",
		focus:    false,
		textSize: 64,
	}
	w.createUserScene.nameInput = InputField{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2)+100,
			200,
			60),
		text:     "",
		focus:    false,
		textSize: 64,
	}
	w.createUserScene.surnameInput = InputField{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2)+200,
			200,
			60,
		),
		text:     "",
		focus:    false,
		textSize: 64,
	}
	w.createUserScene.acceptButton = Button{
		bounds: rl.NewRectangle(
			float32(w.width/2)-100,
			float32(w.height/2+280),
			200,
			60),
		text: "ACCEPT",
	}
}

func (w *Window) updateCreateUserState() {
	if gui.Button(w.createUserScene.acceptButton.bounds, w.createUserScene.acceptButton.text) {
		w.createUserScene.Reset()
		email := w.createUserScene.emailInput.text
		password := w.createUserScene.passwordInput.text
		rePassword := w.createUserScene.rePasswordInput.text
		ruleLevel := w.createUserScene.ruleLevelInput.text
		name := w.createUserScene.nameInput.text
		surname := w.createUserScene.surnameInput.text

		//check input
		if len(email) <= 0 || len(password) <= 0 ||
			len(rePassword) <= 0 || len(ruleLevel) <= 0 ||
			len(name) <= 0 || len(surname) <= 0 {
			w.createUserScene.isError = true
			w.createUserScene.errorMessage = "Zero length error"
			return
		}
		lvl, err := strconv.Atoi(ruleLevel)
		// TODO curr max lvl
		if lvl > 5 || err != nil {
			w.createUserScene.isError = true
			w.createUserScene.errorMessage = "Bad ruleLVL input"
			return
		}
		newUser := User.NewUser(email, password, int32(lvl), name, surname)
		resp := w.ctx.Request(w.serverPID, &Proto.CreateUser{User: newUser}, WaitTime)
		val, err := resp.Result()
		if err != nil {

			w.createUserScene.isError = true
			w.createUserScene.errorMessage = "Actor ctx error"
		}
		if _, ok := val.(*Proto.AcceptCreateUser); ok {
			w.createUserScene.isAccept = true
			w.createUserScene.acceptMessage = "Created successfully"
			w.createUserScene.emailInput.text = ""
			w.createUserScene.passwordInput.text = ""
			w.createUserScene.rePasswordInput.text = ""
			w.createUserScene.ruleLevelInput.text = ""
			w.createUserScene.nameInput.text = ""
			w.createUserScene.surnameInput.text = ""
		}
		if _, ok := val.(*Proto.DenyCreateUser); ok {
			w.createUserScene.isError = true
			w.createUserScene.errorMessage = "DB deny!"
		}
	}

}

func (w *Window) renderCreateUserState() {
	//error
	if w.createUserScene.isError {
		rl.DrawText(w.createUserScene.errorMessage, 0, 0, 32, rl.Red)
	}
	if w.createUserScene.isAccept {
		rl.DrawText(w.createUserScene.acceptMessage, 0, 0, 32, rl.Green)

	}

	if rl.IsMouseButtonPressed(rl.MouseButtonLeft) {
		mousePos := rl.GetMousePosition()
		w.createUserScene.emailInput.focus = false
		w.createUserScene.passwordInput.focus = false
		w.createUserScene.rePasswordInput.focus = false
		w.createUserScene.ruleLevelInput.focus = false
		w.createUserScene.nameInput.focus = false
		w.createUserScene.surnameInput.focus = false

		if rl.CheckCollisionPointRec(mousePos, w.createUserScene.emailInput.bounds) {
			w.createUserScene.emailInput.focus = true
		}
		if rl.CheckCollisionPointRec(mousePos, w.createUserScene.passwordInput.bounds) {
			w.createUserScene.passwordInput.focus = true

		}
		if rl.CheckCollisionPointRec(mousePos, w.createUserScene.rePasswordInput.bounds) {
			w.createUserScene.rePasswordInput.focus = true

		}
		if rl.CheckCollisionPointRec(mousePos, w.createUserScene.ruleLevelInput.bounds) {
			w.createUserScene.ruleLevelInput.focus = true

		}
		if rl.CheckCollisionPointRec(mousePos, w.createUserScene.nameInput.bounds) {
			w.createUserScene.nameInput.focus = true

		}
		if rl.CheckCollisionPointRec(mousePos, w.createUserScene.surnameInput.bounds) {
			w.createUserScene.surnameInput.focus = true
		}
	}
	gui.TextBox(w.createUserScene.emailInput.bounds, &w.createUserScene.emailInput.text, w.createUserScene.emailInput.textSize, w.createUserScene.emailInput.focus)
	gui.TextBox(w.createUserScene.passwordInput.bounds, &w.createUserScene.passwordInput.text, w.createUserScene.passwordInput.textSize, w.createUserScene.passwordInput.focus)
	gui.TextBox(w.createUserScene.rePasswordInput.bounds, &w.createUserScene.rePasswordInput.text, w.createUserScene.rePasswordInput.textSize, w.createUserScene.rePasswordInput.focus)
	gui.TextBox(w.createUserScene.ruleLevelInput.bounds, &w.createUserScene.ruleLevelInput.text, w.createUserScene.ruleLevelInput.textSize, w.createUserScene.ruleLevelInput.focus)
	gui.TextBox(w.createUserScene.nameInput.bounds, &w.createUserScene.nameInput.text, w.createUserScene.nameInput.textSize, w.createUserScene.nameInput.focus)
	gui.TextBox(w.createUserScene.surnameInput.bounds, &w.createUserScene.surnameInput.text, w.createUserScene.surnameInput.textSize, w.createUserScene.surnameInput.focus)

}