fix: fix SEGV for streaming decompress with GC.compact

Author: SpringMT

ext/zstdruby/streaming_decompress.c

@@ -6,6 +6,15 @@ struct streaming_decompress_t {
   size_t buf_size;
 };
 
+static void
+streaming_decompress_mark(void *p)
+{
+  struct streaming_decompress_t *sd = p;
+  // rb_gc_mark((VALUE)sd->ctx);
+  rb_gc_mark(sd->buf);
+  // rb_gc_mark(sd->buf_size);
+}
+
 static void
 streaming_decompress_free(void *p)
 {
@@ -25,7 +34,7 @@ streaming_decompress_memsize(const void *p)
 
 static const rb_data_type_t streaming_decompress_type = {
     "streaming_decompress",
-    { 0, streaming_decompress_free, streaming_decompress_memsize, },
+    { streaming_decompress_mark, streaming_decompress_free, streaming_decompress_memsize, },
      0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 };
 

spec/zstd-ruby-streaming-decompress_spec.rb

@@ -16,5 +16,21 @@
       expect(result).to eq(str)
     end
   end
+
+  describe 'streaming decompress + GC.compact' do
+    it 'shoud work' do
+      # str = SecureRandom.hex(150)
+      str = "foo bar buzz" * 100
+      cstr = Zstd.compress(str)
+      stream = Zstd::StreamingDecompress.new
+      result = ''
+      result << stream.decompress(cstr[0, 5])
+      result << stream.decompress(cstr[5, 5])
+      GC.compact
+      result << stream.decompress(cstr[10..-1])
+      expect(result).to eq(str)
+    end
+  end
+
 end