zlib: instance-ify two methods

Both `Params` and `SetDictionary` take `ZCtx` as an arg, so just make
them both instance methods on `ZCtx`.
PR-URL: #21702
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: maclover7

src/node_zlib.cc

@@ -486,7 +486,7 @@ class ZCtx : public AsyncWrap, public ThreadPoolWork {
  write_js_callback, dictionary, dictionary_len);
 if (!ret) goto end;
 
-SetDictionary(ctx);
+ctx->SetDictionary();
 
  end:
 return args.GetReturnValue().Set(ret);
@@ -496,14 +496,14 @@ class ZCtx : public AsyncWrap, public ThreadPoolWork {
 CHECK(args.Length() == 2 && "params(level, strategy)");
  ZCtx* ctx;
 ASSIGN_OR_RETURN_UNWRAP(&ctx, args.Holder());
-Params(ctx, args[0]->Int32Value(), args[1]->Int32Value());
+ctx->Params(args[0]->Int32Value(), args[1]->Int32Value());
  }
 
 staticvoidReset(const FunctionCallbackInfo<Value> &args) {
  ZCtx* ctx;
 ASSIGN_OR_RETURN_UNWRAP(&ctx, args.Holder());
  ctx->Reset();
-SetDictionary(ctx);
+ctx->SetDictionary();
  }
 
 staticboolInit(ZCtx* ctx, int level, int windowBits, int memLevel,
@@ -577,51 +577,47 @@ class ZCtx : public AsyncWrap, public ThreadPoolWork {
 returntrue;
  }
 
-staticvoidSetDictionary(ZCtx* ctx) {
-if (ctx->dictionary_ == nullptr)
+voidSetDictionary() {
+if (dictionary_ == nullptr)
 return;
 
-ctx->err_ = Z_OK;
+ err_ = Z_OK;
 
-switch (ctx->mode_) {
+switch (mode_) {
 caseDEFLATE:
 caseDEFLATERAW:
- ctx->err_ = deflateSetDictionary(&ctx->strm_,
- ctx->dictionary_,
- ctx->dictionary_len_);
+ err_ = deflateSetDictionary(&strm_, dictionary_, dictionary_len_);
 break;
 caseINFLATERAW:
 // The other inflate cases will have the dictionary set when inflate()
 // returns Z_NEED_DICT in Process()
- ctx->err_ = inflateSetDictionary(&ctx->strm_,
- ctx->dictionary_,
- ctx->dictionary_len_);
+ err_ = inflateSetDictionary(&strm_, dictionary_, dictionary_len_);
 break;
 default:
 break;
  }
 
-if (ctx->err_ != Z_OK) {
-ctx->Error("Failed to set dictionary");
+if (err_ != Z_OK) {
+Error("Failed to set dictionary");
  }
  }
 
-staticvoidParams(ZCtx* ctx, int level, int strategy) {
- AllocScope alloc_scope(ctx);
+voidParams(int level, int strategy) {
+ AllocScope alloc_scope(this);
 
-ctx->err_ = Z_OK;
+ err_ = Z_OK;
 
-switch (ctx->mode_) {
+switch (mode_) {
 caseDEFLATE:
 caseDEFLATERAW:
-ctx->err_ = deflateParams(&ctx->strm_, level, strategy);
+ err_ = deflateParams(&strm_, level, strategy);
 break;
 default:
 break;
  }
 
-if (ctx->err_ != Z_OK && ctx->err_ != Z_BUF_ERROR) {
-ctx->Error("Failed to set parameters");
+if (err_ != Z_OK && err_ != Z_BUF_ERROR) {
+Error("Failed to set parameters");
  }
  }