Make more robust for memory

Signed-off-by: Hiroshi Hatake <[email protected]>

Author: cosmo0920

ext/zstdruby/streaming_compress.c

@@ -157,7 +157,6 @@ rb_streaming_compress_write(int argc, VALUE *argv, VALUE obj)
     const char* input_data = RSTRING_PTR(str);
     size_t input_size = RSTRING_LEN(str);
     ZSTD_inBuffer input = { input_data, input_size, 0 };
-    VALUE result = rb_str_new(0, 0);
 
     while (input.pos < input.size) {
       const char* output_data = RSTRING_PTR(sc->buf);
@@ -166,12 +165,11 @@ rb_streaming_compress_write(int argc, VALUE *argv, VALUE obj)
       if (ZSTD_isError(ret)) {
         rb_raise(rb_eRuntimeError, "compress error error code: %s", ZSTD_getErrorName(ret));
       }
-      /* collect produced bytes */
+      /* Directly append to the pending buffer */
       if (output.pos > 0) {
-        rb_str_cat(result, output.dst, output.pos);
+        rb_str_cat(sc->pending, output.dst, output.pos);
       }
     }
-    rb_str_cat(sc->pending, RSTRING_PTR(result), RSTRING_LEN(result));
     total += RSTRING_LEN(str);
   }
 

ext/zstdruby/streaming_decompress.c

@@ -101,16 +101,22 @@ rb_streaming_decompress_decompress(VALUE obj, VALUE src)
   struct streaming_decompress_t* sd;
   TypedData_Get_Struct(obj, struct streaming_decompress_t, &streaming_decompress_type, sd);
   VALUE result = rb_str_new(0, 0);
-  size_t ret;
-  do {
+
+  while (input.pos < input.size) {
     const char* output_data = RSTRING_PTR(sd->buf);
     ZSTD_outBuffer output = { (void*)output_data, sd->buf_size, 0 };
-    ret = zstd_stream_decompress(sd->dctx, &output, &input, false);
+    size_t const ret = zstd_stream_decompress(sd->dctx, &output, &input, false);
+
     if (ZSTD_isError(ret)) {
       rb_raise(rb_eRuntimeError, "decompress error error code: %s", ZSTD_getErrorName(ret));
     }
-    rb_str_cat(result, output.dst, output.pos);
-  } while (input.pos < input.size && ret > 0);
+    if (output.pos > 0) {
+        rb_str_cat(result, output.dst, output.pos);
+    }
+    if (ret == 0 && output.pos == 0) {
+        break;
+    }
+  }
   return result;
 }