lib/cpp/test/TransportTest.cpp

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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
 *
 *   http://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.
 */
#ifndef _GNU_SOURCE
#define _GNU_SOURCE // needed for getopt_long
#endif

#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <getopt.h>
#include <signal.h>
#include <sstream>
#include <tr1/functional>

#include <boost/mpl/list.hpp>
#include <boost/shared_array.hpp>
#include <boost/random.hpp>
#include <boost/type_traits.hpp>
#include <boost/test/unit_test.hpp>

#include <transport/TBufferTransports.h>
#include <transport/TFDTransport.h>
#include <transport/TFileTransport.h>
#include <transport/TZlibTransport.h>
#include <transport/TSocket.h>

using namespace apache::thrift::transport;

static boost::mt19937 rng;
static const char* tmp_dir = "/tmp";

void initrand(unsigned int seed) {
  rng.seed(seed);
}

class SizeGenerator {
 public:
  virtual ~SizeGenerator() {}
  virtual uint32_t nextSize() = 0;
  virtual std::string describe() const = 0;
};

class ConstantSizeGenerator : public SizeGenerator {
 public:
  ConstantSizeGenerator(uint32_t value) : value_(value) {}
  uint32_t nextSize() { return value_; }
  std::string describe() const {
    std::ostringstream desc;
    desc << value_;
    return desc.str();
  }

 private:
  uint32_t value_;
};

class RandomSizeGenerator : public SizeGenerator {
 public:
  RandomSizeGenerator(uint32_t min, uint32_t max) :
    generator_(rng, boost::uniform_int<int>(min, max)) {}

  uint32_t nextSize() { return generator_(); }

  std::string describe() const {
    std::ostringstream desc;
    desc << "rand(" << getMin() << ", " << getMax() << ")";
    return desc.str();
  }

  uint32_t getMin() const { return generator_.distribution().min(); }
  uint32_t getMax() const { return generator_.distribution().max(); }

 private:
  boost::variate_generator< boost::mt19937&, boost::uniform_int<int> >
    generator_;
};

/**
 * This class exists solely to make the TEST_RW() macro easier to use.
 * - it can be constructed implicitly from an integer
 * - it can contain either a ConstantSizeGenerator or a RandomSizeGenerator
 *   (TEST_RW can't take a SizeGenerator pointer or reference, since it needs
 *   to make a copy of the generator to bind it to the test function.)
 */
class GenericSizeGenerator : public SizeGenerator {
 public:
  GenericSizeGenerator(uint32_t value) :
    generator_(new ConstantSizeGenerator(value)) {}
  GenericSizeGenerator(uint32_t min, uint32_t max) :
    generator_(new RandomSizeGenerator(min, max)) {}

  uint32_t nextSize() { return generator_->nextSize(); }
  std::string describe() const { return generator_->describe(); }

 private:
  boost::shared_ptr<SizeGenerator> generator_;
};

/**************************************************************************
 * Classes to set up coupled transports
 **************************************************************************/

/**
 * Helper class to represent a coupled pair of transports.
 *
 * Data written to the out transport can be read from the in transport.
 *
 * This is used as the base class for the various coupled transport
 * implementations.  It shouldn't be instantiated directly.
 */
template <class Transport_>
class CoupledTransports {
 public:
  typedef Transport_ TransportType;

  CoupledTransports() : in(), out() {}

  boost::shared_ptr<Transport_> in;
  boost::shared_ptr<Transport_> out;

 private:
  CoupledTransports(const CoupledTransports&);
  CoupledTransports &operator=(const CoupledTransports&);
};

/**
 * Coupled TMemoryBuffers
 */
class CoupledMemoryBuffers : public CoupledTransports<TMemoryBuffer> {
 public:
  CoupledMemoryBuffers() :
    buf(new TMemoryBuffer) {
    in = buf;
    out = buf;
  }

  boost::shared_ptr<TMemoryBuffer> buf;
};

/**
 * Helper template class for creating coupled transports that wrap
 * another transport.
 */
template <class WrapperTransport_, class InnerCoupledTransports_>
class CoupledWrapperTransportsT : public CoupledTransports<WrapperTransport_> {
 public:
  CoupledWrapperTransportsT() {
    if (inner_.in) {
      this->in.reset(new WrapperTransport_(inner_.in));
    }
    if (inner_.out) {
      this->out.reset(new WrapperTransport_(inner_.out));
    }
  }

  InnerCoupledTransports_ inner_;
};

/**
 * Coupled TBufferedTransports.
 */
template <class InnerTransport_>
class CoupledBufferedTransportsT :
  public CoupledWrapperTransportsT<TBufferedTransport, InnerTransport_> {
};

typedef CoupledBufferedTransportsT<CoupledMemoryBuffers>
  CoupledBufferedTransports;

/**
 * Coupled TFramedTransports.
 */
template <class InnerTransport_>
class CoupledFramedTransportsT :
  public CoupledWrapperTransportsT<TFramedTransport, InnerTransport_> {
};

typedef CoupledFramedTransportsT<CoupledMemoryBuffers>
  CoupledFramedTransports;

/**
 * Coupled TZlibTransports.
 */
template <class InnerTransport_>
class CoupledZlibTransportsT :
  public CoupledWrapperTransportsT<TZlibTransport, InnerTransport_> {
};

typedef CoupledZlibTransportsT<CoupledMemoryBuffers>
  CoupledZlibTransports;

/**
 * Coupled TFDTransports.
 */
class CoupledFDTransports : public CoupledTransports<TFDTransport> {
 public:
  CoupledFDTransports() {
    int pipes[2];

    if (pipe(pipes) != 0) {
      return;
    }

    in.reset(new TFDTransport(pipes[0], TFDTransport::CLOSE_ON_DESTROY));
    out.reset(new TFDTransport(pipes[1], TFDTransport::CLOSE_ON_DESTROY));
  }
};

/**
 * Coupled TSockets
 */
class CoupledSocketTransports : public CoupledTransports<TSocket> {
 public:
  CoupledSocketTransports() {
    int sockets[2];
    if (socketpair(PF_UNIX, SOCK_STREAM, 0, sockets) != 0) {
      return;
    }

    in.reset(new TSocket(sockets[0]));
    out.reset(new TSocket(sockets[1]));
  }
};

/**
 * Coupled TFileTransports
 */
class CoupledFileTransports : public CoupledTransports<TFileTransport> {
 public:
  CoupledFileTransports() {
    // Create a temporary file to use
    size_t filename_len = strlen(tmp_dir) + 32;
    filename = new char[filename_len];
    snprintf(filename, filename_len,
             "%s/thrift.transport_test.XXXXXX", tmp_dir);
    fd = mkstemp(filename);
    if (fd < 0) {
      return;
    }

    in.reset(new TFileTransport(filename, true));
    out.reset(new TFileTransport(filename));
  }

  ~CoupledFileTransports() {
    if (fd >= 0) {
      close(fd);
      unlink(filename);
    }
    delete[] filename;
  }

  char* filename;
  int fd;
};

/**
 * Wrapper around another CoupledTransports implementation that exposes the
 * transports as TTransport pointers.
 *
 * This is used since accessing a transport via a "TTransport*" exercises a
 * different code path than using the base pointer class.  As part of the
 * template code changes, most transport methods are no longer virtual.
 */
template <class CoupledTransports_>
class CoupledTTransports : public CoupledTransports<TTransport> {
 public:
  CoupledTTransports() : transports() {
    in = transports.in;
    out = transports.out;
  }

  CoupledTransports_ transports;
};

/**
 * Wrapper around another CoupledTransports implementation that exposes the
 * transports as TBufferBase pointers.
 *
 * This can only be instantiated with a transport type that is a subclass of
 * TBufferBase.
 */
template <class CoupledTransports_>
class CoupledBufferBases : public CoupledTransports<TBufferBase> {
 public:
  CoupledBufferBases() : transports() {
    in = transports.in;
    out = transports.out;
  }

  CoupledTransports_ transports;
};

/**************************************************************************
 * Alarm handling code for use in tests that check the transport blocking
 * semantics.
 *
 * If the transport ends up blocking, we don't want to hang forever.  We use
 * SIGALRM to fire schedule signal to wake up and try to write data so the
 * transport will unblock.
 *
 * It isn't really the safest thing in the world to be mucking around with
 * complicated global data structures in a signal handler.  It should probably
 * be okay though, since we know the main thread should always be blocked in a
 * read() request when the signal handler is running.
 **************************************************************************/

struct TriggerInfo {
  TriggerInfo(int seconds, const boost::shared_ptr<TTransport>& transport,
              uint32_t writeLength) :
    timeoutSeconds(seconds),
    transport(transport),
    writeLength(writeLength),
    next(NULL) {}

  int timeoutSeconds;
  boost::shared_ptr<TTransport> transport;
  uint32_t writeLength;
  TriggerInfo* next;
};

TriggerInfo* triggerInfo;
unsigned int numTriggersFired;

void set_alarm();

void alarm_handler(int signum) {
  // The alarm timed out, which almost certainly means we're stuck
  // on a transport that is incorrectly blocked.
  ++numTriggersFired;

  // Note: we print messages to stdout instead of stderr, since
  // tools/test/runner only records stdout messages in the failure messages for
  // boost tests.  (boost prints its test info to stdout.)
  printf("Timeout alarm expired; attempting to unblock transport\n");
  if (triggerInfo == NULL) {
    printf("  trigger stack is empty!\n");
  }

  // Pop off the first TriggerInfo.
  // If there is another one, schedule an alarm for it.
  TriggerInfo* info = triggerInfo;
  triggerInfo = info->next;
  set_alarm();

  // Write some data to the transport to hopefully unblock it.
  uint8_t buf[info->writeLength];
  memset(buf, 'b', info->writeLength);
  info->transport->write(buf, info->writeLength);
  info->transport->flush();

  delete info;
}

void set_alarm() {
  if (triggerInfo == NULL) {
    // clear any alarm
    alarm(0);
    return;
  }

  struct sigaction action;
  memset(&action, 0, sizeof(action));
  action.sa_handler = alarm_handler;
  action.sa_flags = SA_ONESHOT;
  sigemptyset(&action.sa_mask);
  sigaction(SIGALRM, &action, NULL);

  alarm(triggerInfo->timeoutSeconds);
}

/**
 * Add a trigger to be scheduled "seconds" seconds after the
 * last currently scheduled trigger.
 *
 * (Note that this is not "seconds" from now.  That might be more logical, but
 * would require slightly more complicated sorting, rather than just appending
 * to the end.)
 */
void add_trigger(unsigned int seconds,
                 const boost::shared_ptr<TTransport> &transport,
                 uint32_t write_len) {
  TriggerInfo* info = new TriggerInfo(seconds, transport, write_len);

  if (triggerInfo == NULL) {
    // This is the first trigger.
    // Set triggerInfo, and schedule the alarm
    triggerInfo = info;
    set_alarm();
  } else {
    // Add this trigger to the end of the list
    TriggerInfo* prev = triggerInfo;
    while (prev->next) {
      prev = prev->next;
    }

    prev->next = info;
  }
}

void clear_triggers() {
  TriggerInfo *info = triggerInfo;
  alarm(0);
  triggerInfo = NULL;
  numTriggersFired = 0;

  while (info != NULL) {
    TriggerInfo* next = info->next;
    delete info;
    info = next;
  }
}

void set_trigger(unsigned int seconds,
                 const boost::shared_ptr<TTransport> &transport,
                 uint32_t write_len) {
  clear_triggers();
  add_trigger(seconds, transport, write_len);
}

/**************************************************************************
 * Test functions
 **************************************************************************/

/**
 * Test interleaved write and read calls.
 *
 * Generates a buffer totalSize bytes long, then writes it to the transport,
 * and verifies the written data can be read back correctly.
 *
 * Mode of operation:
 * - call wChunkGenerator to figure out how large of a chunk to write
 *   - call wSizeGenerator to get the size for individual write() calls,
 *     and do this repeatedly until the entire chunk is written.
 * - call rChunkGenerator to figure out how large of a chunk to read
 *   - call rSizeGenerator to get the size for individual read() calls,
 *     and do this repeatedly until the entire chunk is read.
 * - repeat until the full buffer is written and read back,
 *   then compare the data read back against the original buffer
 *
 *
 * - If any of the size generators return 0, this means to use the maximum
 *   possible size.
 *
 * - If maxOutstanding is non-zero, write chunk sizes will be chosen such that
 *   there are never more than maxOutstanding bytes waiting to be read back.
 */
template <class CoupledTransports>
void test_rw(uint32_t totalSize,
             SizeGenerator& wSizeGenerator,
             SizeGenerator& rSizeGenerator,
             SizeGenerator& wChunkGenerator,
             SizeGenerator& rChunkGenerator,
             uint32_t maxOutstanding) {
  CoupledTransports transports;
  BOOST_REQUIRE(transports.in != NULL);
  BOOST_REQUIRE(transports.out != NULL);

  boost::shared_array<uint8_t> wbuf =
    boost::shared_array<uint8_t>(new uint8_t[totalSize]);
  boost::shared_array<uint8_t> rbuf =
    boost::shared_array<uint8_t>(new uint8_t[totalSize]);

  // store some data in wbuf
  for (uint32_t n = 0; n < totalSize; ++n) {
    wbuf[n] = (n & 0xff);
  }
  // clear rbuf
  memset(rbuf.get(), 0, totalSize);

  uint32_t total_written = 0;
  uint32_t total_read = 0;
  while (total_read < totalSize) {
    // Determine how large a chunk of data to write
    uint32_t wchunk_size = wChunkGenerator.nextSize();
    if (wchunk_size == 0 || wchunk_size > totalSize - total_written) {
      wchunk_size = totalSize - total_written;
    }

    // Make sure (total_written - total_read) + wchunk_size
    // is less than maxOutstanding
    if (maxOutstanding > 0 &&
        wchunk_size > maxOutstanding - (total_written - total_read)) {
      wchunk_size = maxOutstanding - (total_written - total_read);
    }

    // Write the chunk
    uint32_t chunk_written = 0;
    while (chunk_written < wchunk_size) {
      uint32_t write_size = wSizeGenerator.nextSize();
      if (write_size == 0 || write_size > wchunk_size - chunk_written) {
        write_size = wchunk_size - chunk_written;
      }

      transports.out->write(wbuf.get() + total_written, write_size);
      chunk_written += write_size;
      total_written += write_size;
    }

    // Flush the data, so it will be available in the read transport
    // Don't flush if wchunk_size is 0.  (This should only happen if
    // total_written == totalSize already, and we're only reading now.)
    if (wchunk_size > 0) {
      transports.out->flush();
    }

    // Determine how large a chunk of data to read back
    uint32_t rchunk_size = rChunkGenerator.nextSize();
    if (rchunk_size == 0 || rchunk_size > total_written - total_read) {
      rchunk_size = total_written - total_read;
    }

    // Read the chunk
    uint32_t chunk_read = 0;
    while (chunk_read < rchunk_size) {
      uint32_t read_size = rSizeGenerator.nextSize();
      if (read_size == 0 || read_size > rchunk_size - chunk_read) {
        read_size = rchunk_size - chunk_read;
      }

      int bytes_read = -1;
      try {
        bytes_read = transports.in->read(rbuf.get() + total_read, read_size);
      } catch (TTransportException& e) {
        BOOST_FAIL("read(pos=" << total_read << ", size=" << read_size <<
                   ") threw exception \"" << e.what() <<
                   "\"; written so far: " << total_written << " / " <<
                   totalSize << " bytes");
      }

      BOOST_REQUIRE_MESSAGE(bytes_read > 0,
                            "read(pos=" << total_read << ", size=" <<
                            read_size << ") returned " << bytes_read <<
                            "; written so far: " << total_written << " / " <<
                            totalSize << " bytes");
      chunk_read += bytes_read;
      total_read += bytes_read;
    }
  }

  // make sure the data read back is identical to the data written
  BOOST_CHECK_EQUAL(memcmp(rbuf.get(), wbuf.get(), totalSize), 0);
}

template <class CoupledTransports>
void test_read_part_available() {
  CoupledTransports transports;
  BOOST_REQUIRE(transports.in != NULL);
  BOOST_REQUIRE(transports.out != NULL);

  uint8_t write_buf[16];
  uint8_t read_buf[16];
  memset(write_buf, 'a', sizeof(write_buf));

  // Attemping to read 10 bytes when only 9 are available should return 9
  // immediately.
  transports.out->write(write_buf, 9);
  transports.out->flush();
  set_trigger(3, transports.out, 1);
  uint32_t bytes_read = transports.in->read(read_buf, 10);
  BOOST_CHECK_EQUAL(numTriggersFired, 0);
  BOOST_CHECK_EQUAL(bytes_read, 9);

  clear_triggers();
}

template <class CoupledTransports>
void test_read_partial_midframe() {
  CoupledTransports transports;
  BOOST_REQUIRE(transports.in != NULL);
  BOOST_REQUIRE(transports.out != NULL);

  uint8_t write_buf[16];
  uint8_t read_buf[16];
  memset(write_buf, 'a', sizeof(write_buf));

  // Attempt to read 10 bytes, when only 9 are available, but after we have
  // already read part of the data that is available.  This exercises a
  // different code path for several of the transports.
  //
  // For transports that add their own framing (e.g., TFramedTransport and
  // TFileTransport), the two flush calls break up the data in to a 10 byte
  // frame and a 3 byte frame.  The first read then puts us partway through the
  // first frame, and then we attempt to read past the end of that frame, and
  // through the next frame, too.
  //
  // For buffered transports that perform read-ahead (e.g.,
  // TBufferedTransport), the read-ahead will most likely see all 13 bytes
  // written on the first read.  The next read will then attempt to read past
  // the end of the read-ahead buffer.
  //
  // Flush 10 bytes, then 3 bytes.  This creates 2 separate frames for
  // transports that track framing internally.
  transports.out->write(write_buf, 10);
  transports.out->flush();
  transports.out->write(write_buf, 3);
  transports.out->flush();

  // Now read 4 bytes, so that we are partway through the written data.
  uint32_t bytes_read = transports.in->read(read_buf, 4);
  BOOST_CHECK_EQUAL(bytes_read, 4);

  // Now attempt to read 10 bytes.  Only 9 more are available.
  //
  // We should be able to get all 9 bytes, but it might take multiple read
  // calls, since it is valid for read() to return fewer bytes than requested.
  // (Most transports do immediately return 9 bytes, but the framing transports
  // tend to only return to the end of the current frame, which is 6 bytes in
  // this case.)
  uint32_t total_read = 0;
  while (total_read < 9) {
    set_trigger(3, transports.out, 1);
    bytes_read = transports.in->read(read_buf, 10);
    BOOST_REQUIRE_EQUAL(numTriggersFired, 0);
    BOOST_REQUIRE_GT(bytes_read, 0);
    total_read += bytes_read;
    BOOST_REQUIRE_LE(total_read, 9);
  }

  BOOST_CHECK_EQUAL(total_read, 9);

  clear_triggers();
}

template <class CoupledTransports>
void test_borrow_part_available() {
  CoupledTransports transports;
  BOOST_REQUIRE(transports.in != NULL);
  BOOST_REQUIRE(transports.out != NULL);

  uint8_t write_buf[16];
  uint8_t read_buf[16];
  memset(write_buf, 'a', sizeof(write_buf));

  // Attemping to borrow 10 bytes when only 9 are available should return NULL
  // immediately.
  transports.out->write(write_buf, 9);
  transports.out->flush();
  set_trigger(3, transports.out, 1);
  uint32_t borrow_len = 10;
  const uint8_t* borrowed_buf = transports.in->borrow(read_buf, &borrow_len);
  BOOST_CHECK_EQUAL(numTriggersFired, 0);
  BOOST_CHECK(borrowed_buf == NULL);

  clear_triggers();
}

template <class CoupledTransports>
void test_read_none_available() {
  CoupledTransports transports;
  BOOST_REQUIRE(transports.in != NULL);
  BOOST_REQUIRE(transports.out != NULL);

  uint8_t write_buf[16];
  uint8_t read_buf[16];
  memset(write_buf, 'a', sizeof(write_buf));

  // Attempting to read when no data is available should either block until
  // some data is available, or fail immediately.  (e.g., TSocket blocks,
  // TMemoryBuffer just fails.)
  //
  // If the transport blocks, it should succeed once some data is available,
  // even if less than the amount requested becomes available.
  set_trigger(1, transports.out, 2);
  add_trigger(1, transports.out, 8);
  uint32_t bytes_read = transports.in->read(read_buf, 10);
  if (bytes_read == 0) {
    BOOST_CHECK_EQUAL(numTriggersFired, 0);
    clear_triggers();
  } else {
    BOOST_CHECK_EQUAL(numTriggersFired, 1);
    BOOST_CHECK_EQUAL(bytes_read, 2);
  }

  clear_triggers();
}

template <class CoupledTransports>
void test_borrow_none_available() {
  CoupledTransports transports;
  BOOST_REQUIRE(transports.in != NULL);
  BOOST_REQUIRE(transports.out != NULL);

  uint8_t write_buf[16];
  memset(write_buf, 'a', sizeof(write_buf));

  // Attempting to borrow when no data is available should fail immediately
  set_trigger(1, transports.out, 10);
  uint32_t borrow_len = 10;
  const uint8_t* borrowed_buf = transports.in->borrow(NULL, &borrow_len);
  BOOST_CHECK(borrowed_buf == NULL);
  BOOST_CHECK_EQUAL(numTriggersFired, 0);

  clear_triggers();
}

/**************************************************************************
 * Test case generation
 *
 * Pretty ugly and annoying.  This would be much easier if we the unit test
 * framework didn't force each test to be a separate function.
 * - Writing a completely separate function definition for each of these would
 *   result in a lot of repetitive boilerplate code.
 * - Combining many tests into a single function makes it more difficult to
 *   tell precisely which tests failed.  It also means you can't get a progress
 *   update after each test, and the tests are already fairly slow.
 * - Similar registration could be acheived with BOOST_TEST_CASE_TEMPLATE,
 *   but it requires a lot of awkward MPL code, and results in useless test
 *   case names.  (The names are generated from std::type_info::name(), which
 *   is compiler-dependent.  gcc returns mangled names.)
 **************************************************************************/

#define ADD_TEST_RW(CoupledTransports, totalSize, ...) \
    addTestRW< CoupledTransports >(BOOST_STRINGIZE(CoupledTransports), \
                                   totalSize, ## __VA_ARGS__);

#define TEST_RW(CoupledTransports, totalSize, ...) \
  do { \
    /* Add the test as specified, to test the non-virtual function calls */ \
    ADD_TEST_RW(CoupledTransports, totalSize, ## __VA_ARGS__); \
    /* \
     * Also test using the transport as a TTransport*, to test \
     * the read_virt()/write_virt() calls \
     */ \
    ADD_TEST_RW(CoupledTTransports<CoupledTransports>, \
                totalSize, ## __VA_ARGS__); \
    /* Test wrapping the transport with TBufferedTransport */ \
    ADD_TEST_RW(CoupledBufferedTransportsT<CoupledTransports>, \
                totalSize, ## __VA_ARGS__); \
    /* Test wrapping the transport with TFramedTransports */ \
    ADD_TEST_RW(CoupledFramedTransportsT<CoupledTransports>, \
                totalSize, ## __VA_ARGS__); \
    /* Test wrapping the transport with TZlibTransport */ \
    ADD_TEST_RW(CoupledZlibTransportsT<CoupledTransports>, \
                totalSize, ## __VA_ARGS__); \
  } while (0)

#define ADD_TEST_BLOCKING(CoupledTransports) \
    addTestBlocking< CoupledTransports >(BOOST_STRINGIZE(CoupledTransports));

#define TEST_BLOCKING_BEHAVIOR(CoupledTransports) \
  ADD_TEST_BLOCKING(CoupledTransports); \
  ADD_TEST_BLOCKING(CoupledTTransports<CoupledTransports>); \
  ADD_TEST_BLOCKING(CoupledBufferedTransportsT<CoupledTransports>); \
  ADD_TEST_BLOCKING(CoupledFramedTransportsT<CoupledTransports>); \
  ADD_TEST_BLOCKING(CoupledZlibTransportsT<CoupledTransports>);

class TransportTestGen {
 public:
  TransportTestGen(boost::unit_test::test_suite* suite,
                   float sizeMultiplier) :
      suite_(suite),
      sizeMultiplier_(sizeMultiplier) {}

  void generate() {
    GenericSizeGenerator rand4k(1, 4096);

    /*
     * We do the basically the same set of tests for each transport type,
     * although we tweak the parameters in some places.
     */

    // TMemoryBuffer tests
    TEST_RW(CoupledMemoryBuffers, 1024*1024, 0, 0);
    TEST_RW(CoupledMemoryBuffers, 1024*256, rand4k, rand4k);
    TEST_RW(CoupledMemoryBuffers, 1024*256, 167, 163);
    TEST_RW(CoupledMemoryBuffers, 1024*16, 1, 1);

    TEST_RW(CoupledMemoryBuffers, 1024*256, 0, 0, rand4k, rand4k);
    TEST_RW(CoupledMemoryBuffers, 1024*256, rand4k, rand4k, rand4k, rand4k);
    TEST_RW(CoupledMemoryBuffers, 1024*256, 167, 163, rand4k, rand4k);
    TEST_RW(CoupledMemoryBuffers, 1024*16, 1, 1, rand4k, rand4k);

    TEST_BLOCKING_BEHAVIOR(CoupledMemoryBuffers);

    // TFDTransport tests
    // Since CoupledFDTransports tests with a pipe, writes will block
    // if there is too much outstanding unread data in the pipe.
    uint32_t fd_max_outstanding = 4096;
    TEST_RW(CoupledFDTransports, 1024*1024, 0, 0,
            0, 0, fd_max_outstanding);
    TEST_RW(CoupledFDTransports, 1024*256, rand4k, rand4k,
            0, 0, fd_max_outstanding);
    TEST_RW(CoupledFDTransports, 1024*256, 167, 163,
            0, 0, fd_max_outstanding);
    TEST_RW(CoupledFDTransports, 1024*16, 1, 1,
            0, 0, fd_max_outstanding);

    TEST_RW(CoupledFDTransports, 1024*256, 0, 0,
            rand4k, rand4k, fd_max_outstanding);
    TEST_RW(CoupledFDTransports, 1024*256, rand4k, rand4k,
            rand4k, rand4k, fd_max_outstanding);
    TEST_RW(CoupledFDTransports, 1024*256, 167, 163,
            rand4k, rand4k, fd_max_outstanding);
    TEST_RW(CoupledFDTransports, 1024*16, 1, 1,
            rand4k, rand4k, fd_max_outstanding);

    TEST_BLOCKING_BEHAVIOR(CoupledFDTransports);

    // TSocket tests
    uint32_t socket_max_outstanding = 4096;
    TEST_RW(CoupledSocketTransports, 1024*1024, 0, 0,
            0, 0, socket_max_outstanding);
    TEST_RW(CoupledSocketTransports, 1024*256, rand4k, rand4k,
            0, 0, socket_max_outstanding);
    TEST_RW(CoupledSocketTransports, 1024*256, 167, 163,
            0, 0, socket_max_outstanding);
    // Doh.  Apparently writing to a socket has some additional overhead for
    // each send() call.  If we have more than ~400 outstanding 1-byte write
    // requests, additional send() calls start blocking.
    TEST_RW(CoupledSocketTransports, 1024*16, 1, 1,
            0, 0, 400);
    TEST_RW(CoupledSocketTransports, 1024*256, 0, 0,
            rand4k, rand4k, socket_max_outstanding);
    TEST_RW(CoupledSocketTransports, 1024*256, rand4k, rand4k,
            rand4k, rand4k, socket_max_outstanding);
    TEST_RW(CoupledSocketTransports, 1024*256, 167, 163,
            rand4k, rand4k, socket_max_outstanding);
    TEST_RW(CoupledSocketTransports, 1024*16, 1, 1,
            rand4k, rand4k, 400);

    TEST_BLOCKING_BEHAVIOR(CoupledSocketTransports);

    // TFileTransport tests
    // We use smaller buffer sizes here, since TFileTransport is fairly slow.
    //
    // TFileTransport can't write more than 16MB at once
    uint32_t max_write_at_once = 1024*1024*16 - 4;
    TEST_RW(CoupledFileTransports, 1024*1024, max_write_at_once, 0);
    TEST_RW(CoupledFileTransports, 1024*128, rand4k, rand4k);
    TEST_RW(CoupledFileTransports, 1024*128, 167, 163);
    TEST_RW(CoupledFileTransports, 1024*2, 1, 1);

    TEST_RW(CoupledFileTransports, 1024*64, 0, 0, rand4k, rand4k);
    TEST_RW(CoupledFileTransports, 1024*64,
            rand4k, rand4k, rand4k, rand4k);
    TEST_RW(CoupledFileTransports, 1024*64, 167, 163, rand4k, rand4k);
    TEST_RW(CoupledFileTransports, 1024*2, 1, 1, rand4k, rand4k);

    TEST_BLOCKING_BEHAVIOR(CoupledFileTransports);

    // Add some tests that access TBufferedTransport and TFramedTransport
    // via TTransport pointers and TBufferBase pointers.
    ADD_TEST_RW(CoupledTTransports<CoupledBufferedTransports>,
                1024*1024, rand4k, rand4k, rand4k, rand4k);
    ADD_TEST_RW(CoupledBufferBases<CoupledBufferedTransports>,
                1024*1024, rand4k, rand4k, rand4k, rand4k);
    ADD_TEST_RW(CoupledTTransports<CoupledFramedTransports>,
                1024*1024, rand4k, rand4k, rand4k, rand4k);
    ADD_TEST_RW(CoupledBufferBases<CoupledFramedTransports>,
                1024*1024, rand4k, rand4k, rand4k, rand4k);

    // Test using TZlibTransport via a TTransport pointer
    ADD_TEST_RW(CoupledTTransports<CoupledZlibTransports>,
                1024*1024, rand4k, rand4k, rand4k, rand4k);
  }

 private:
  template <class CoupledTransports>
  void addTestRW(const char* transport_name, uint32_t totalSize,
                 GenericSizeGenerator wSizeGen, GenericSizeGenerator rSizeGen,
                 GenericSizeGenerator wChunkSizeGen = 0,
                 GenericSizeGenerator rChunkSizeGen = 0,
                 uint32_t maxOutstanding = 0,
                 uint32_t expectedFailures = 0) {
    // adjust totalSize by the specified sizeMultiplier_ first
    totalSize = static_cast<uint32_t>(totalSize * sizeMultiplier_);

    std::ostringstream name;
    name << transport_name << "::test_rw(" << totalSize << ", " <<
      wSizeGen.describe() << ", " << rSizeGen.describe() << ", " <<
      wChunkSizeGen.describe() << ", " << rChunkSizeGen.describe() << ", " <<
      maxOutstanding << ")";

    boost::unit_test::callback0<> test_func =
      std::tr1::bind(test_rw<CoupledTransports>, totalSize,
                     wSizeGen, rSizeGen, wChunkSizeGen, rChunkSizeGen,
                     maxOutstanding);
    boost::unit_test::test_case* tc =
      boost::unit_test::make_test_case(test_func, name.str());
    suite_->add(tc, expectedFailures);
  };

  template <class CoupledTransports>
  void addTestBlocking(const char* transportName,
                       uint32_t expectedFailures = 0) {
    char name[1024];
    boost::unit_test::test_case* tc;

    snprintf(name, sizeof(name), "%s::test_read_part_available()",
             transportName);
    tc = boost::unit_test::make_test_case(
          test_read_part_available<CoupledTransports>, name);
    suite_->add(tc, expectedFailures);

    snprintf(name, sizeof(name), "%s::test_read_partial_midframe()",
             transportName);
    tc = boost::unit_test::make_test_case(
          test_read_partial_midframe<CoupledTransports>, name);
    suite_->add(tc, expectedFailures);

    snprintf(name, sizeof(name), "%s::test_read_none_available()",
             transportName);
    tc = boost::unit_test::make_test_case(
          test_read_none_available<CoupledTransports>, name);
    suite_->add(tc, expectedFailures);

    snprintf(name, sizeof(name), "%s::test_borrow_part_available()",
             transportName);
    tc = boost::unit_test::make_test_case(
          test_borrow_part_available<CoupledTransports>, name);
    suite_->add(tc, expectedFailures);

    snprintf(name, sizeof(name), "%s::test_borrow_none_available()",
             transportName);
    tc = boost::unit_test::make_test_case(
          test_borrow_none_available<CoupledTransports>, name);
    suite_->add(tc, expectedFailures);
  }

  boost::unit_test::test_suite* suite_;
  // sizeMultiplier_ is configurable via the command line, and allows the
  // user to adjust between smaller buffers that can be tested quickly,
  // or larger buffers that more thoroughly exercise the code, but take
  // longer.
  float sizeMultiplier_;
};

/**************************************************************************
 * General Initialization
 **************************************************************************/

void print_usage(FILE* f, const char* argv0) {
  fprintf(f, "Usage: %s [boost_options] [options]\n", argv0);
  fprintf(f, "Options:\n");
  fprintf(f, "  --seed=<N>, -s <N>\n");
  fprintf(f, "  --tmp-dir=DIR, -t DIR\n");
  fprintf(f, "  --help\n");
}

struct Options {
  int seed;
  bool haveSeed;
  float sizeMultiplier;
};

void parse_args(int argc, char* argv[], Options* options) {
  bool have_seed = false;
  options->sizeMultiplier = 1;

  struct option long_opts[] = {
    { "help", false, NULL, 'h' },
    { "seed", true, NULL, 's' },
    { "tmp-dir", true, NULL, 't' },
    { "size-multiplier", true, NULL, 'x' },
    { NULL, 0, NULL, 0 }
  };

  while (true) {
    optopt = 1;
    int optchar = getopt_long(argc, argv, "hs:t:x:", long_opts, NULL);
    if (optchar == -1) {
      break;
    }

    switch (optchar) {
      case 't':
        tmp_dir = optarg;
        break;
      case 's': {
        char *endptr;
        options->seed = strtol(optarg, &endptr, 0);
        if (endptr == optarg || *endptr != '\0') {
          fprintf(stderr, "invalid seed value \"%s\": must be an integer\n",
                  optarg);
          exit(1);
        }
        have_seed = true;
        break;
      }
      case 'h':
        print_usage(stdout, argv[0]);
        exit(0);
      case 'x': {
        char *endptr;
        options->sizeMultiplier = strtof(optarg, &endptr);
        if (endptr == optarg || *endptr != '\0') {
          fprintf(stderr, "invalid size multiplier \"%s\": must be a number\n",
                  optarg);
          exit(1);
        }
        if (options->sizeMultiplier < 0) {
          fprintf(stderr, "invalid size multiplier \"%s\": "
                  "must be non-negative\n", optarg);
          exit(1);
        }
        break;
      }
      case '?':
        exit(1);
      default:
        // Only happens if someone adds another option to the optarg string,
        // but doesn't update the switch statement to handle it.
        fprintf(stderr, "unknown option \"-%c\"\n", optchar);
        exit(1);
    }
  }

  if (!have_seed) {
    // choose a seed now if the user didn't specify one
    struct timespec t;
    clock_gettime(CLOCK_REALTIME, &t);
    options->seed = t.tv_sec + t.tv_nsec;
  }
}

boost::unit_test::test_suite* init_unit_test_suite(int argc, char* argv[]) {
  // Parse arguments
  Options options;
  parse_args(argc, argv, &options);

  initrand(options.seed);

  boost::unit_test::test_suite* suite =
    &boost::unit_test::framework::master_test_suite();
  suite->p_name.value = "TransportTest";
  TransportTestGen transport_test_generator(suite, options.sizeMultiplier);
  transport_test_generator.generate();

  return NULL;
}