expose cursor from render state

src/main/java/dev/jlibghostty/RenderCursorStyle.java

@@ -0,0 +1,27 @@
+package dev.jlibghostty;
+
+public enum RenderCursorStyle {
+    BAR(0),
+    BLOCK(1),
+    UNDERLINE(2),
+    BLOCK_HOLLOW(3);
+
+    private final int nativeValue;
+
+    RenderCursorStyle(int nativeValue) {
+        this.nativeValue = nativeValue;
+    }
+
+    public int nativeValue() {
+        return nativeValue;
+    }
+
+    static RenderCursorStyle fromNative(int value) {
+        for (RenderCursorStyle style : values()) {
+            if (style.nativeValue == value) {
+                return style;
+            }
+        }
+        throw new IllegalArgumentException("Unknown render cursor style: " + value);
+    }
+}

src/main/java/dev/jlibghostty/RenderState.java

@@ -24,10 +24,30 @@ public final class RenderState implements AutoCloseable {
 
     public RenderStateSnapshot snapshot() {
         ensureOpen();
+        boolean cursorViewportHasValue = library.renderStateGetBoolean(
+            handle,
+            GhosttyLibrary.RENDER_STATE_DATA_CURSOR_VIEWPORT_HAS_VALUE
+        );
+
         return new RenderStateSnapshot(
             library.renderStateGetU16(handle, GhosttyLibrary.RENDER_STATE_DATA_COLS),
             library.renderStateGetU16(handle, GhosttyLibrary.RENDER_STATE_DATA_ROWS),
             library.renderStateGetI32(handle, GhosttyLibrary.RENDER_STATE_DATA_DIRTY),
+            RenderCursorStyle.fromNative(
+                library.renderStateGetI32(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_VISUAL_STYLE)
+            ),
+            library.renderStateGetBoolean(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_VISIBLE),
+            library.renderStateGetBoolean(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_BLINKING),
+            library.renderStateGetBoolean(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_PASSWORD_INPUT),
+            cursorViewportHasValue,
+            cursorViewportHasValue
+                ? library.renderStateGetU16(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_VIEWPORT_X)
+                : -1,
+            cursorViewportHasValue
+                ? library.renderStateGetU16(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_VIEWPORT_Y)
+                : -1,
+            cursorViewportHasValue
+                && library.renderStateGetBoolean(handle, GhosttyLibrary.RENDER_STATE_DATA_CURSOR_VIEWPORT_WIDE_TAIL),
             rows()
         );
     }

src/main/java/dev/jlibghostty/RenderStateSnapshot.java

@@ -2,7 +2,20 @@ package dev.jlibghostty;
 
 import java.util.List;
 
-public record RenderStateSnapshot(int columns, int rows, int dirty, List<RenderRow> renderRows) {
+public record RenderStateSnapshot(
+    int columns,
+    int rows,
+    int dirty,
+    RenderCursorStyle cursorStyle,
+    boolean cursorVisible,
+    boolean cursorBlinking,
+    boolean cursorPasswordInput,
+    boolean cursorViewportHasValue,
+    int cursorViewportX,
+    int cursorViewportY,
+    boolean cursorViewportWideTail,
+    List<RenderRow> renderRows
+) {
     public RenderStateSnapshot {
         renderRows = List.copyOf(renderRows);
     }

src/main/java/dev/jlibghostty/internal/GhosttyLibrary.java

@@ -70,6 +70,14 @@ public final class GhosttyLibrary {
     public static final int RENDER_STATE_DATA_ROWS = 2;
     public static final int RENDER_STATE_DATA_DIRTY = 3;
     public static final int RENDER_STATE_DATA_ROW_ITERATOR = 4;
+    public static final int RENDER_STATE_DATA_CURSOR_VISUAL_STYLE = 10;
+    public static final int RENDER_STATE_DATA_CURSOR_VISIBLE = 11;
+    public static final int RENDER_STATE_DATA_CURSOR_BLINKING = 12;
+    public static final int RENDER_STATE_DATA_CURSOR_PASSWORD_INPUT = 13;
+    public static final int RENDER_STATE_DATA_CURSOR_VIEWPORT_HAS_VALUE = 14;
+    public static final int RENDER_STATE_DATA_CURSOR_VIEWPORT_X = 15;
+    public static final int RENDER_STATE_DATA_CURSOR_VIEWPORT_Y = 16;
+    public static final int RENDER_STATE_DATA_CURSOR_VIEWPORT_WIDE_TAIL = 17;
 
     public static final int RENDER_STATE_ROW_DATA_DIRTY = 1;
     public static final int RENDER_STATE_ROW_DATA_CELLS = 3;
@@ -627,6 +635,17 @@ public final class GhosttyLibrary {
         }
     }
 
+    public boolean renderStateGetBoolean(MemorySegment state, int key) {
+        try (Arena arena = Arena.ofConfined()) {
+            MemorySegment out = arena.allocate(C_BOOL);
+            int result = (int) renderStateGet.invoke(state, key, out);
+            checkResult("ghostty_render_state_get", result);
+            return out.get(C_BOOL, 0);
+        } catch (Throwable t) {
+            return rethrow(t);
+        }
+    }
+
     public List<RenderRow> renderStateRows(MemorySegment state) {
         MemorySegment iterator = renderStateRowIteratorNew();
         try {

src/test/java/dev/jlibghostty/GhosttySmokeTest.java

@@ -43,6 +43,14 @@ public final class GhosttySmokeTest {
             if (!renderedHello) {
                 throw new AssertionError("render state should contain written text");
             }
+            if (renderSnapshot.cursorViewportHasValue()) {
+                if (renderSnapshot.cursorViewportX() < 0 || renderSnapshot.cursorViewportX() >= renderSnapshot.columns()
+                    || renderSnapshot.cursorViewportY() < 0 || renderSnapshot.cursorViewportY() >= renderSnapshot.rows()) {
+                    throw new AssertionError("cursor viewport position out of bounds: " + renderSnapshot);
+                }
+            } else if (renderSnapshot.cursorViewportX() != -1 || renderSnapshot.cursorViewportY() != -1) {
+                throw new AssertionError("cursor viewport position should be -1 when absent: " + renderSnapshot);
+            }
             renderSnapshot.renderRows().stream()
                 .flatMap(row -> row.cells().stream())
                 .forEach(cell -> {