#include #include /* Test that we read the bits in the correct order */ TEST (BufferTests, GetNextBitTest) { reset_pos(); /* The 4-byte buffer in memory */ unsigned char buf[4] = {175, /* = 10101111 */ 240, /* = 11110000 */ 15, /* = 00001111 */ 204}; /* = 11001100 */ /* * The real stream order. * If the bytes are laid out in memory as * [b0b1..b7] [b8...b15] ... * Then the correct stream order is: * [b7...b0] [b15...b8] ... */ int stream_order[32] = {1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1}; for (int i = 0; i < 32; i++) { // TODO this cast should probably not be necessary // change type signature to unsigned char in inflate ASSERT_EQ (get_next_bit((char *) buf), stream_order[i]); } } /* * Test that we get the correct numerical value when * reading from a buffer. * In this test, all integers are interpreted in * STREAM ORDER. That is, if the bitstream * is (b0, b1, b2, ..., bn), we interpret * b0 as the MSB and bn as the LSB. Note that the order * of the bitstream is not necessarily the order that * the bits are laid out in memory; see get_next_bit(). */ TEST (BufferTests, StreamOrderTest) { reset_pos(); unsigned char buf[2] = {220, /* = 11011100 */ 145}; /* = 10010001 */ /* First 3 bits are 001 */ ASSERT_EQ (get_n_bits((char *) buf, 3, false), 1); /* Next 5 are 11011 */ ASSERT_EQ (get_n_bits((char *) buf, 5, false), 27); /* Next 2 are 10 */ ASSERT_EQ (get_n_bits((char *) buf, 2, false), 2); /* Next 6 are 001001 */ ASSERT_EQ (get_n_bits((char *) buf, 6, false), 9); } /* * Like the test above, but interprets integers in REVERSE STREAM ORDER. * That is, if we read in the bitstream (b0, b1, ..., bn), * b0 is the LSB and bn is the MSB. */ TEST (BufferTests, RevStreamOrderTest) { reset_pos(); unsigned char buf[2] = {220, /* = 11011100 */ 145}; /* = 10010001 */ /* First 3 bits are 001 */ ASSERT_EQ (get_n_bits((char *) buf, 3, true), 4); /* Next 5 are 11011 */ ASSERT_EQ (get_n_bits((char *) buf, 5, true), 27); /* Next 2 are 10 */ ASSERT_EQ (get_n_bits((char *) buf, 2, true), 1); /* Next 6 are 001001 */ ASSERT_EQ (get_n_bits((char *) buf, 6, true), 36); } /* Test making a huffman tree from a sequence of lengths */ TEST (HuffmanTests, TestMakeHuffman) { int n_symbols = 8; int lens[8] = {3, 3, 3, 3, 3, 2, 4, 4}; huffman_t *hf = make_huffman(lens, n_symbols); int bl_counts[MAX_LENGTH + 1] = {0, 0, 1, 5, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; /* Check bl_counts */ for (int i = 0; i < MAX_LENGTH + 1; i++) { ASSERT_EQ (hf->bl_counts[i], bl_counts[i]); } /* * Check min_codes for entries with non-zero bl_count * It doesn't really matter what the other entries are. */ ASSERT_EQ (hf->min_codes[2], 0); ASSERT_EQ (hf->min_codes[3], 2); ASSERT_EQ (hf->min_codes[4], 14); /* Check that the alphabet arrays were populated correctly. */ ASSERT_EQ (hf->alphabet[2][0], 5); for (int i = 0; i < 5; i++) ASSERT_EQ (hf->alphabet[3][i], i); ASSERT_EQ (hf->alphabet[4][0], 6); ASSERT_EQ (hf->alphabet[4][1], 7); destroy_huffman(hf); } /* * Test that make_huffman does not assign a code to symbols with * a length of 0. */ TEST (HuffmanTests, TestMakeHuffmanZeroLens) { int n_symbols = 8; int lens[8] = {1, 0, 2, 3, 3, 0, 4, 3}; huffman_t *hf = make_huffman(lens, n_symbols); int bl_counts[MAX_LENGTH + 1] = {0, 1, 1, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; /* Check bl_counts */ for (int i = 0; i < MAX_LENGTH + 1; i++) { ASSERT_EQ (hf->bl_counts[i], bl_counts[i]); } /* Check min_codes */ ASSERT_EQ (hf->min_codes[1], 0); ASSERT_EQ (hf->min_codes[2], 2); ASSERT_EQ (hf->min_codes[3], 6); ASSERT_EQ (hf->min_codes[4], 18); /* Check alphabet. */ ASSERT_EQ (hf->alphabet[1][0], 0); /* 1 and 5 are not used! (length = 0) */ ASSERT_EQ (hf->alphabet[2][0], 2); ASSERT_EQ (hf->alphabet[3][0], 3); ASSERT_EQ (hf->alphabet[3][1], 4); ASSERT_EQ (hf->alphabet[3][2], 7); ASSERT_EQ (hf->alphabet[4][0], 6); destroy_huffman(hf); } // TODO TEST (HuffmanTests, TestReadChunk) { } TEST (HuffmanTests, TestReadLens) {} int main(int argc, char **argv) { ::testing::InitGoogleTest(&argc, argv); return RUN_ALL_TESTS(); }