test/fuzz-libghostty: basic afl++-based fuzzer for libghostty

test/fuzz-libghostty/src/lib.zig

@@ -0,0 +1,11 @@
+const std = @import("std");
+const ghostty_vt = @import("ghostty-vt");
+
+pub export fn ghostty_fuzz_parser(
+    input_ptr: [*]const u8,
+    input_len: usize,
+) callconv(.c) void {
+    var p: ghostty_vt.Parser = .init();
+    defer p.deinit();
+    for (input_ptr[0..input_len]) |byte| _ = p.next(byte);
+}

test/fuzz-libghostty/src/main.c

@@ -0,0 +1,27 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+void ghostty_fuzz_parser(const uint8_t *input, size_t input_len);
+
+int main(int argc, char **argv) {
+    uint8_t buf[4096];
+    size_t len = 0;
+    FILE *f = stdin;
+
+    if (argc > 1) {
+        f = fopen(argv[1], "rb");
+        if (f == NULL) {
+            return 0;
+        }
+    }
+
+    len = fread(buf, 1, sizeof(buf), f);
+
+    if (argc > 1) {
+        fclose(f);
+    }
+
+    ghostty_fuzz_parser(buf, len);
+    return 0;
+}