scroggo@google.com | 83fd2c7 | 2013-09-26 21:35:39 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2013 Google Inc. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
| 7 | |
| 8 | #include "SkFrontBufferedStream.h" |
| 9 | #include "SkRefCnt.h" |
| 10 | #include "SkTypes.h" |
| 11 | #include "Test.h" |
| 12 | |
| 13 | static void test_read(skiatest::Reporter* reporter, SkStream* bufferedStream, |
| 14 | const void* expectations, size_t bytesToRead) { |
| 15 | // output for reading bufferedStream. |
| 16 | SkAutoMalloc storage(bytesToRead); |
| 17 | |
| 18 | size_t bytesRead = bufferedStream->read(storage.get(), bytesToRead); |
| 19 | REPORTER_ASSERT(reporter, bytesRead == bytesToRead || bufferedStream->isAtEnd()); |
| 20 | REPORTER_ASSERT(reporter, memcmp(storage.get(), expectations, bytesRead) == 0); |
| 21 | } |
| 22 | |
| 23 | static void test_rewind(skiatest::Reporter* reporter, |
| 24 | SkStream* bufferedStream, bool shouldSucceed) { |
| 25 | const bool success = bufferedStream->rewind(); |
| 26 | REPORTER_ASSERT(reporter, success == shouldSucceed); |
| 27 | } |
| 28 | |
| 29 | // All tests will buffer this string, and compare output to the original. |
| 30 | // The string is long to ensure that all of our lengths being tested are |
| 31 | // smaller than the string length. |
| 32 | const char gAbcs[] = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwx"; |
| 33 | |
| 34 | // Tests reading the stream across boundaries of what has been buffered so far and what |
| 35 | // the total buffer size is. |
| 36 | static void test_incremental_buffering(skiatest::Reporter* reporter, size_t bufferSize) { |
| 37 | SkMemoryStream memStream(gAbcs, strlen(gAbcs), false); |
| 38 | |
| 39 | SkAutoTUnref<SkStream> bufferedStream(SkFrontBufferedStream::Create(&memStream, bufferSize)); |
| 40 | |
| 41 | // First, test reading less than the max buffer size. |
| 42 | test_read(reporter, bufferedStream, gAbcs, bufferSize / 2); |
| 43 | |
| 44 | // Now test rewinding back to the beginning and reading less than what was |
| 45 | // already buffered. |
| 46 | test_rewind(reporter, bufferedStream, true); |
| 47 | test_read(reporter, bufferedStream, gAbcs, bufferSize / 4); |
| 48 | |
| 49 | // Now test reading part of what was buffered, and buffering new data. |
| 50 | test_read(reporter, bufferedStream, gAbcs + bufferedStream->getPosition(), bufferSize / 2); |
| 51 | |
| 52 | // Now test reading what was buffered, buffering new data, and |
| 53 | // reading directly from the stream. |
| 54 | test_rewind(reporter, bufferedStream, true); |
| 55 | test_read(reporter, bufferedStream, gAbcs, bufferSize << 1); |
| 56 | |
| 57 | // We have reached the end of the buffer, so rewinding will fail. |
| 58 | // This test assumes that the stream is larger than the buffer; otherwise the |
| 59 | // result of rewind should be true. |
| 60 | test_rewind(reporter, bufferedStream, false); |
| 61 | } |
| 62 | |
| 63 | static void test_perfectly_sized_buffer(skiatest::Reporter* reporter, size_t bufferSize) { |
| 64 | SkMemoryStream memStream(gAbcs, strlen(gAbcs), false); |
| 65 | SkAutoTUnref<SkStream> bufferedStream(SkFrontBufferedStream::Create(&memStream, bufferSize)); |
| 66 | |
| 67 | // Read exactly the amount that fits in the buffer. |
| 68 | test_read(reporter, bufferedStream, gAbcs, bufferSize); |
| 69 | |
| 70 | // Rewinding should succeed. |
| 71 | test_rewind(reporter, bufferedStream, true); |
| 72 | |
| 73 | // Once again reading buffered info should succeed |
| 74 | test_read(reporter, bufferedStream, gAbcs, bufferSize); |
| 75 | |
| 76 | // Read past the size of the buffer. At this point, we cannot return. |
| 77 | test_read(reporter, bufferedStream, gAbcs + bufferedStream->getPosition(), 1); |
| 78 | test_rewind(reporter, bufferedStream, false); |
| 79 | } |
| 80 | |
| 81 | static void test_skipping(skiatest::Reporter* reporter, size_t bufferSize) { |
| 82 | SkMemoryStream memStream(gAbcs, strlen(gAbcs), false); |
| 83 | SkAutoTUnref<SkStream> bufferedStream(SkFrontBufferedStream::Create(&memStream, bufferSize)); |
| 84 | |
| 85 | // Skip half the buffer. |
| 86 | bufferedStream->skip(bufferSize / 2); |
| 87 | |
| 88 | // Rewind, then read part of the buffer, which should have been read. |
| 89 | test_rewind(reporter, bufferedStream, true); |
| 90 | test_read(reporter, bufferedStream, gAbcs, bufferSize / 4); |
| 91 | |
| 92 | // Now skip beyond the buffered piece, but still within the total buffer. |
| 93 | bufferedStream->skip(bufferSize / 2); |
| 94 | |
| 95 | // Test that reading will still work. |
| 96 | test_read(reporter, bufferedStream, gAbcs + bufferedStream->getPosition(), bufferSize / 4); |
| 97 | |
| 98 | test_rewind(reporter, bufferedStream, true); |
| 99 | test_read(reporter, bufferedStream, gAbcs, bufferSize); |
| 100 | } |
| 101 | |
| 102 | // A custom class whose isAtEnd behaves the way Android's stream does - since it is an adaptor to a |
| 103 | // Java InputStream, it does not know that it is at the end until it has attempted to read beyond |
| 104 | // the end and failed. Used by test_read_beyond_buffer. |
| 105 | class AndroidLikeMemoryStream : public SkMemoryStream { |
| 106 | public: |
| 107 | AndroidLikeMemoryStream(void* data, size_t size, bool ownMemory) |
| 108 | : INHERITED(data, size, ownMemory) |
| 109 | , fIsAtEnd(false) {} |
| 110 | |
| 111 | size_t read(void* dst, size_t requested) SK_OVERRIDE { |
| 112 | size_t bytesRead = this->INHERITED::read(dst, requested); |
| 113 | if (bytesRead < requested) { |
| 114 | fIsAtEnd = true; |
| 115 | } |
| 116 | return bytesRead; |
| 117 | } |
| 118 | |
| 119 | bool isAtEnd() const SK_OVERRIDE { |
| 120 | return fIsAtEnd; |
| 121 | } |
| 122 | |
| 123 | private: |
| 124 | bool fIsAtEnd; |
| 125 | typedef SkMemoryStream INHERITED; |
| 126 | }; |
| 127 | |
| 128 | // This test ensures that buffering the exact length of the stream and attempting to read beyond it |
| 129 | // does not invalidate the buffer. |
| 130 | static void test_read_beyond_buffer(skiatest::Reporter* reporter, size_t bufferSize) { |
| 131 | // Use a stream that behaves like Android's stream. |
| 132 | AndroidLikeMemoryStream memStream((void*)gAbcs, bufferSize, false); |
| 133 | |
| 134 | // Create a buffer that matches the length of the stream. |
| 135 | SkAutoTUnref<SkStream> bufferedStream(SkFrontBufferedStream::Create(&memStream, bufferSize)); |
| 136 | |
| 137 | // Attempt to read one more than the bufferSize |
| 138 | test_read(reporter, bufferedStream.get(), gAbcs, bufferSize + 1); |
| 139 | test_rewind(reporter, bufferedStream.get(), true); |
| 140 | |
| 141 | // Ensure that the initial read did not invalidate the buffer. |
| 142 | test_read(reporter, bufferedStream, gAbcs, bufferSize); |
| 143 | } |
| 144 | |
| 145 | static void test_buffers(skiatest::Reporter* reporter, size_t bufferSize) { |
| 146 | test_incremental_buffering(reporter, bufferSize); |
| 147 | test_perfectly_sized_buffer(reporter, bufferSize); |
| 148 | test_skipping(reporter, bufferSize); |
| 149 | test_read_beyond_buffer(reporter, bufferSize); |
| 150 | } |
| 151 | |
| 152 | static void TestStreams(skiatest::Reporter* reporter) { |
| 153 | // Test 6 and 64, which are used by Android, as well as another arbitrary length. |
| 154 | test_buffers(reporter, 6); |
| 155 | test_buffers(reporter, 15); |
| 156 | test_buffers(reporter, 64); |
| 157 | } |
| 158 | |
| 159 | #include "TestClassDef.h" |
| 160 | DEFINE_TESTCLASS("FrontBufferedStream", FrontBufferedStreamTestClass, TestStreams) |