int main()
{
// Seed random number generator to produce different results every time
srand(time(NULL));
// Set the number of symbols (i.e. the generation size in RLNC
// terminology) and the size of a symbol in bytes
uint8_t max_symbols = 6;
uint8_t max_symbol_size = 100;
int32_t codec = kodoc_sliding_window;
int32_t finite_field = kodoc_binary8;
// In the following we will make an encoder/decoder factory.
// The factories are used to build actual encoders/decoders
kodoc_factory_t encoder_factory =
kodoc_new_encoder_factory(codec, finite_field,
max_symbols, max_symbol_size);
kodoc_factory_t decoder_factory =
kodoc_new_decoder_factory(codec, finite_field,
max_symbols, max_symbol_size);
// If we wanted to build an encoder or decoder with a smaller number of
// symbols or a different symbol size, then this can be adjusted using the
// following functions:
// kodoc_factory_set_symbols(...)
// kodoc_factory_set_symbol_size(...)
// We cannot exceed the maximum values which was used when building
// the factory.
kodoc_coder_t encoder = kodoc_factory_build_coder(encoder_factory);
kodoc_coder_t decoder = kodoc_factory_build_coder(decoder_factory);
// Allocate some storage for a "payload" the payload is what we would
// eventually send over a network
uint32_t payload_size = kodoc_payload_size(encoder);
uint8_t* payload = (uint8_t*) malloc(payload_size);
// Allocate some data to encode. In this case we make a buffer
// with the same size as the encoder's block size (the max.
// amount a single encoder can encode)
uint32_t block_size = kodoc_block_size(encoder);
uint8_t* data_in = (uint8_t*) malloc(block_size);
uint8_t* data_out = (uint8_t*) malloc(block_size);
kodoc_set_mutable_symbols(decoder, data_out, block_size);
uint8_t feedback_size = (uint8_t) kodoc_feedback_size(encoder);
uint8_t* feedback = (uint8_t*) malloc(feedback_size);
uint32_t i = 0;
//Just for fun - fill data_in with random data
for (; i < block_size; ++i)
{
data_in[i] = rand() % 256;
}
// Install a custom trace function for the decoder
kodoc_set_trace_callback(decoder, trace_callback, NULL);
while (!kodoc_is_complete(decoder))
{
// Insert a new symbol until the encoder is full
if (kodoc_rank(encoder) < max_symbols)
{
uint32_t rank = kodoc_rank(encoder);
uint8_t* symbol = data_in + (rank * max_symbol_size);
kodoc_set_const_symbol(encoder, rank, symbol, max_symbol_size);
printf("Symbol %d added to the encoder\n", rank);
}
// Only send packets if the encoder has more data than the decoder
if (kodoc_rank(encoder) == kodoc_rank(decoder))
{
continue;
}
// Write an encoded packet into the payload buffer
kodoc_write_payload(encoder, payload);
printf("Encoded packet generated\n");
// Here we simulate that we are losing 50% of the packets
if (rand() % 2)
{
printf("Packet dropped on channel\n\n");
continue;
}
printf("Decoder received packet\n");
// Packet got through - pass that packet to the decoder
kodoc_read_payload(decoder, payload);
printf("Encoder rank = %d\n", kodoc_rank(encoder));
printf("Decoder rank = %d\n", kodoc_rank(decoder));
printf("Decoder uncoded = %d\n", kodoc_symbols_uncoded(decoder));
printf("Decoder partially decoded = %d\n",
kodoc_symbols_partially_decoded(decoder));
// Transmit the feedback
kodoc_write_feedback(decoder, feedback);
// Note that the feedback packets can also be lost in a real network,
// but here we deliver all of them for the sake of simplicity
printf("Received feedback from decoder\n\n");
kodoc_read_feedback(encoder, feedback);
}
if (memcmp(data_in, data_out, block_size) == 0)
{
printf("Data decoded correctly\n");
}
else
{
printf("Unexpected failure to decode, please file a bug report :)\n");
}
free(data_in);
free(data_out);
free(payload);
free(feedback);
kodoc_delete_coder(encoder);
kodoc_delete_coder(decoder);
kodoc_delete_factory(encoder_factory);
kodoc_delete_factory(decoder_factory);
return 0;
}
void test_sliding_window(uint32_t max_symbols, uint32_t max_symbol_size,
int32_t finite_field)
{
kodoc_factory_t encoder_factory = kodoc_new_encoder_factory(
kodoc_sliding_window, finite_field, max_symbols, max_symbol_size);
kodoc_factory_t decoder_factory = kodoc_new_decoder_factory(
kodoc_sliding_window, finite_field, max_symbols, max_symbol_size);
kodoc_coder_t encoder = kodoc_factory_build_coder(encoder_factory);
kodoc_coder_t decoder = kodoc_factory_build_coder(decoder_factory);
EXPECT_EQ(max_symbols,kodoc_factory_max_symbols(encoder_factory));
EXPECT_EQ(max_symbol_size,kodoc_factory_max_symbol_size(encoder_factory));
EXPECT_EQ(max_symbols, kodoc_symbols(encoder));
EXPECT_EQ(max_symbol_size,kodoc_symbol_size(encoder));
EXPECT_EQ(max_symbols, kodoc_factory_max_symbols(decoder_factory));
EXPECT_EQ(max_symbol_size, kodoc_factory_max_symbol_size(decoder_factory));
EXPECT_EQ(max_symbols, kodoc_symbols(decoder));
EXPECT_EQ(max_symbol_size, kodoc_symbol_size(decoder));
EXPECT_EQ(max_symbols * max_symbol_size, kodoc_block_size(encoder));
EXPECT_EQ(max_symbols * max_symbol_size, kodoc_block_size(decoder));
EXPECT_TRUE(kodoc_factory_max_payload_size(encoder_factory) >=
kodoc_payload_size(encoder));
EXPECT_TRUE(kodoc_factory_max_payload_size(decoder_factory) >=
kodoc_payload_size(decoder));
EXPECT_EQ(kodoc_factory_max_payload_size(encoder_factory),
kodoc_factory_max_payload_size(decoder_factory));
uint32_t feedback_size = 0;
EXPECT_EQ(kodoc_feedback_size(encoder), kodoc_feedback_size(decoder));
feedback_size = kodoc_feedback_size(encoder);
EXPECT_TRUE(feedback_size > 0);
// Allocate some storage for a "payload" the payload is what we would
// eventually send over a network
uint32_t payload_size = kodoc_payload_size(encoder);
uint8_t* payload = (uint8_t*) malloc(payload_size);
uint8_t* feedback = (uint8_t*) malloc(feedback_size);
// Allocate some data to encode. In this case we make a buffer
// with the same size as the encoder's block size (the max.
// amount a single encoder can encode)
uint32_t block_size = kodoc_block_size(encoder);
uint8_t* data_in = (uint8_t*) malloc(block_size);
uint8_t* data_out = (uint8_t*) malloc(block_size);
// Just for fun - fill the data with random data
for (uint32_t i = 0; i < block_size; ++i)
data_in[i] = rand() % 256;
// Install a custom trace function for the encoder and decoder
kodoc_set_trace_callback(encoder, encoder_trace_callback, NULL);
kodoc_set_trace_callback(decoder, decoder_trace_callback, NULL);
// Assign the data buffer to the encoder so that we may start
// to produce encoded symbols from it
kodoc_set_const_symbols(encoder, data_in, block_size);
kodoc_set_mutable_symbols(decoder, data_out, block_size);
EXPECT_TRUE(kodoc_is_complete(decoder) == 0);
while (!kodoc_is_complete(decoder))
{
// Encode the packet into the payload buffer
uint32_t payload_used = kodoc_write_payload(encoder, payload);
EXPECT_TRUE(payload_used <= kodoc_payload_size(encoder));
// Pass that packet to the decoder
kodoc_read_payload(decoder, payload);
// All payloads must be innovative due to the perfect feedback
EXPECT_TRUE(kodoc_is_partially_complete(decoder) != 0);
kodoc_write_feedback(decoder, feedback);
kodoc_read_feedback(encoder, feedback);
}
EXPECT_TRUE(kodoc_is_complete(decoder) != 0);
// Check if we properly decoded the data
EXPECT_EQ(memcmp(data_in, data_out, block_size), 0);
// Check that the trace functions were called at least once
EXPECT_GT(encoder_trace_called, 0U);
EXPECT_GT(decoder_trace_called, 0U);
free(data_in);
free(data_out);
free(payload);
free(feedback);
kodoc_delete_coder(encoder);
kodoc_delete_coder(decoder);
kodoc_delete_factory(encoder_factory);
kodoc_delete_factory(decoder_factory);
}