| // Copyright 2019 The Wuffs Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // https://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package cgozstd |
| |
| import ( |
| "bytes" |
| "io" |
| "strings" |
| "testing" |
| ) |
| |
| const ( |
| // compressedMoreN is 15 bytes of zstd frame: |
| // |
| // There are two forms, depending on the zstd-the-library version used for |
| // compression. They differ only in the WD byte. |
| // |
| // \x28\xb5\x2f\xfd \x00 \x50 \x31\x00\x00 \x4d\x6f\x72\x65\x21\x0a |
| // \x28\xb5\x2f\xfd \x00 \x58 \x31\x00\x00 \x4d\x6f\x72\x65\x21\x0a |
| // Magic----------- FHD- WD-- BH---------- BlockData--------------- |
| // |
| // Frame Header Descriptor: no flags set. |
| // Window Descriptor: Exponent=10, Mantissa=0, Window_Size=1MiB. |
| // or: Exponent=11, Mantissa=0, Window_Size=2MiB. |
| // Block Header: Last_Block=1, Block_Type=0 (Raw_Block), Block_Size=6. |
| // Block Data: the literal bytes "More!\n". |
| compressedMore0 = "\x28\xb5\x2f\xfd\x00\x50\x31\x00\x00\x4d\x6f\x72\x65\x21\x0a" |
| compressedMore1 = "\x28\xb5\x2f\xfd\x00\x58\x31\x00\x00\x4d\x6f\x72\x65\x21\x0a" |
| |
| uncompressedMore = "More!\n" |
| ) |
| |
| func TestRoundTrip(tt *testing.T) { |
| if !cgoEnabled { |
| tt.Skip("cgo is not enabled") |
| } |
| |
| wr := &WriterRecycler{} |
| defer wr.Close() |
| w := &Writer{} |
| wr.Bind(w) |
| |
| rr := &ReaderRecycler{} |
| defer rr.Close() |
| r := &Reader{} |
| rr.Bind(r) |
| |
| for i := 0; i < 3; i++ { |
| buf := &bytes.Buffer{} |
| |
| // Compress. |
| { |
| if err := w.Reset(buf, nil, 0); err != nil { |
| w.Close() |
| tt.Fatalf("i=%d: Reset: %v", i, err) |
| } |
| if _, err := w.Write([]byte(uncompressedMore)); err != nil { |
| w.Close() |
| tt.Fatalf("i=%d: Write: %v", i, err) |
| } |
| if err := w.Close(); err != nil { |
| tt.Fatalf("i=%d: Close: %v", i, err) |
| } |
| } |
| |
| compressed := buf.String() |
| if (compressed != compressedMore0) && (compressed != compressedMore1) { |
| tt.Fatalf("i=%d: compressed\ngot % 02x\nwant % 02x\nor % 02x", |
| i, compressed, compressedMore0, compressedMore1) |
| } |
| |
| // Uncompress. |
| { |
| if err := r.Reset(strings.NewReader(compressed), nil); err != nil { |
| r.Close() |
| tt.Fatalf("i=%d: Reset: %v", i, err) |
| } |
| gotBytes, err := io.ReadAll(r) |
| if err != nil { |
| r.Close() |
| tt.Fatalf("i=%d: ReadAll: %v", i, err) |
| } |
| if got, want := string(gotBytes), uncompressedMore; got != want { |
| r.Close() |
| tt.Fatalf("i=%d:\ngot %q\nwant %q", i, got, want) |
| } |
| if err := r.Close(); err != nil { |
| tt.Fatalf("i=%d: Close: %v", i, err) |
| } |
| } |
| } |
| } |
| |
| func TestDictionary(tt *testing.T) { |
| if !cgoEnabled { |
| tt.Skip("cgo is not enabled") |
| } |
| |
| const ( |
| abc = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" |
| uncompressed = abc + "123" |
| ) |
| |
| for _, withDict := range []bool{false, true} { |
| buf := &bytes.Buffer{} |
| dictionary, name := []byte(nil), "sans dictionary" |
| if withDict { |
| dictionary, name = []byte(abc), "with dictionary" |
| } |
| |
| w := &Writer{} |
| if err := w.Reset(buf, dictionary, 0); err != nil { |
| w.Close() |
| tt.Fatalf("%s: Reset: %v", name, err) |
| } |
| if _, err := w.Write([]byte(uncompressed)); err != nil { |
| w.Close() |
| tt.Fatalf("%s: Write: %v", name, err) |
| } |
| if err := w.Close(); err != nil { |
| tt.Fatalf("%s: Close: %v", name, err) |
| } |
| |
| compressed := buf.String() |
| if withDict { |
| if n := buf.Len(); n >= 30 { |
| tt.Fatalf("%s: compressed length: got %d, want < 30", name, n) |
| } |
| } else { |
| if n := buf.Len(); n < 50 { |
| tt.Fatalf("%s: compressed length: got %d, want >= 50", name, n) |
| } |
| } |
| |
| r := &Reader{} |
| if err := r.Reset(strings.NewReader(compressed), dictionary); err != nil { |
| r.Close() |
| tt.Fatalf("%s: Reset: %v", name, err) |
| } |
| gotBytes, err := io.ReadAll(r) |
| if err != nil { |
| r.Close() |
| tt.Fatalf("%s: ReadAll: %v", name, err) |
| } |
| if got, want := string(gotBytes), uncompressed; got != want { |
| r.Close() |
| tt.Fatalf("%s:\ngot %q\nwant %q", name, got, want) |
| } |
| if err := r.Close(); err != nil { |
| tt.Fatalf("%s: Close: %v", name, err) |
| } |
| } |
| } |