mirror of https://github.com/google/snappy.git
577 lines
19 KiB
C++
577 lines
19 KiB
C++
// Copyright 2011 Google Inc. All Rights Reserved.
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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// * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// Various stubs for the unit tests for the open-source version of Snappy.
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#include "snappy-test.h"
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#ifdef HAVE_WINDOWS_H
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#define WIN32_LEAN_AND_MEAN
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#include <windows.h>
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#endif
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#include <algorithm>
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DEFINE_bool(run_microbenchmarks, true,
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"Run microbenchmarks before doing anything else.");
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namespace snappy {
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string ReadTestDataFile(const string& base) {
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string contents;
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const char* srcdir = getenv("srcdir"); // This is set by Automake.
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if (srcdir) {
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File::ReadFileToStringOrDie(
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string(srcdir) + "/testdata/" + base, &contents);
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} else {
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File::ReadFileToStringOrDie("testdata/" + base, &contents);
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}
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return contents;
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}
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string StringPrintf(const char* format, ...) {
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char buf[4096];
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va_list ap;
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va_start(ap, format);
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vsnprintf(buf, sizeof(buf), format, ap);
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va_end(ap);
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return buf;
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}
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bool benchmark_running = false;
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int64 benchmark_real_time_us = 0;
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int64 benchmark_cpu_time_us = 0;
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string *benchmark_label = NULL;
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int64 benchmark_bytes_processed = 0;
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void ResetBenchmarkTiming() {
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benchmark_real_time_us = 0;
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benchmark_cpu_time_us = 0;
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}
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struct timeval benchmark_start_real;
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#ifdef WIN32
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FILETIME benchmark_start_cpu;
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#else // WIN32
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struct rusage benchmark_start_cpu;
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#endif // WIN32
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void StartBenchmarkTiming() {
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gettimeofday(&benchmark_start_real, NULL);
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#ifdef WIN32
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FILETIME dummy;
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CHECK(GetProcessTimes(
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GetCurrentProcess(), &dummy, &dummy, &dummy, &benchmark_start_cpu));
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#else
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if (getrusage(RUSAGE_SELF, &benchmark_start_cpu) == -1) {
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perror("getrusage(RUSAGE_SELF)");
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exit(1);
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}
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#endif
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benchmark_running = true;
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}
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void StopBenchmarkTiming() {
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if (!benchmark_running) {
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return;
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}
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struct timeval benchmark_stop_real;
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gettimeofday(&benchmark_stop_real, NULL);
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benchmark_real_time_us +=
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1000000 * (benchmark_stop_real.tv_sec - benchmark_start_real.tv_sec);
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benchmark_real_time_us +=
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(benchmark_stop_real.tv_usec - benchmark_start_real.tv_usec);
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#ifdef WIN32
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FILETIME benchmark_stop_cpu, dummy;
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CHECK(GetProcessTimes(
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GetCurrentProcess(), &dummy, &dummy, &dummy, &benchmark_stop_cpu));
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ULARGE_INTEGER start_ulargeint;
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start_ulargeint.LowPart = benchmark_start_cpu.dwLowDateTime;
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start_ulargeint.HighPart = benchmark_start_cpu.dwHighDateTime;
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ULARGE_INTEGER stop_ulargeint;
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stop_ulargeint.LowPart = benchmark_stop_cpu.dwLowDateTime;
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stop_ulargeint.HighPart = benchmark_stop_cpu.dwHighDateTime;
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benchmark_cpu_time_us +=
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(stop_ulargeint.QuadPart - start_ulargeint.QuadPart + 5) / 10;
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#else // WIN32
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struct rusage benchmark_stop_cpu;
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if (getrusage(RUSAGE_SELF, &benchmark_stop_cpu) == -1) {
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perror("getrusage(RUSAGE_SELF)");
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exit(1);
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}
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benchmark_cpu_time_us += 1000000 * (benchmark_stop_cpu.ru_utime.tv_sec -
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benchmark_start_cpu.ru_utime.tv_sec);
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benchmark_cpu_time_us += (benchmark_stop_cpu.ru_utime.tv_usec -
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benchmark_start_cpu.ru_utime.tv_usec);
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#endif // WIN32
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benchmark_running = false;
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}
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void SetBenchmarkLabel(const string& str) {
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if (benchmark_label) {
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delete benchmark_label;
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}
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benchmark_label = new string(str);
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}
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void SetBenchmarkBytesProcessed(int64 bytes) {
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benchmark_bytes_processed = bytes;
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}
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struct BenchmarkRun {
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int64 real_time_us;
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int64 cpu_time_us;
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};
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struct BenchmarkCompareCPUTime {
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bool operator() (const BenchmarkRun& a, const BenchmarkRun& b) const {
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return a.real_time_us < b.real_time_us;
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}
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};
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void Benchmark::Run() {
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for (int test_case_num = start_; test_case_num <= stop_; ++test_case_num) {
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// Run a few iterations first to find out approximately how fast
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// the benchmark is.
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const int kCalibrateIterations = 100;
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ResetBenchmarkTiming();
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StartBenchmarkTiming();
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(*function_)(kCalibrateIterations, test_case_num);
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StopBenchmarkTiming();
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// Let each test case run for about 200ms.
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// Run five times and pick the median.
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const int kNumRuns = 5;
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const int kMedianPos = kNumRuns / 2;
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int num_iterations = 200000 * kCalibrateIterations / benchmark_real_time_us;
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BenchmarkRun benchmark_runs[kNumRuns];
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for (int run = 0; run < kNumRuns; ++run) {
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ResetBenchmarkTiming();
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StartBenchmarkTiming();
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(*function_)(num_iterations, test_case_num);
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StopBenchmarkTiming();
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benchmark_runs[run].real_time_us = benchmark_real_time_us;
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benchmark_runs[run].cpu_time_us = benchmark_cpu_time_us;
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}
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sort(benchmark_runs, benchmark_runs + kNumRuns, BenchmarkCompareCPUTime());
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int64 real_time_us = benchmark_runs[kMedianPos].real_time_us;
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int64 cpu_time_us = benchmark_runs[kMedianPos].cpu_time_us;
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int64 bytes_per_second = benchmark_bytes_processed * 1000000 / cpu_time_us;
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string heading = StringPrintf("%s/%d", name_.c_str(), test_case_num);
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string human_readable_speed;
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if (bytes_per_second < 1024) {
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human_readable_speed = StringPrintf("%dB/s", bytes_per_second);
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} else if (bytes_per_second < 1024 * 1024) {
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human_readable_speed = StringPrintf(
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"%.1fkB/s", bytes_per_second / 1024.0f);
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} else if (bytes_per_second < 1024 * 1024 * 1024) {
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human_readable_speed = StringPrintf(
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"%.1fMB/s", bytes_per_second / (1024.0f * 1024.0f));
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} else {
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human_readable_speed = StringPrintf(
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"%.1fGB/s", bytes_per_second / (1024.0f * 1024.0f * 1024.0f));
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}
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fprintf(stderr,
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#ifdef WIN32
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"%-18s %10I64d %10I64d %10d %s %s\n",
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#else
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"%-18s %10lld %10lld %10d %s %s\n",
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#endif
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heading.c_str(),
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static_cast<long long>(real_time_us * 1000 / num_iterations),
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static_cast<long long>(cpu_time_us * 1000 / num_iterations),
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num_iterations,
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human_readable_speed.c_str(),
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benchmark_label->c_str());
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}
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}
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#ifdef HAVE_LIBZ
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ZLib::ZLib()
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: comp_init_(false),
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uncomp_init_(false) {
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Reinit();
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}
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ZLib::~ZLib() {
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if (comp_init_) { deflateEnd(&comp_stream_); }
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if (uncomp_init_) { inflateEnd(&uncomp_stream_); }
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}
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void ZLib::Reinit() {
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compression_level_ = Z_DEFAULT_COMPRESSION;
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window_bits_ = MAX_WBITS;
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mem_level_ = 8; // DEF_MEM_LEVEL
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if (comp_init_) {
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deflateEnd(&comp_stream_);
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comp_init_ = false;
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}
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if (uncomp_init_) {
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inflateEnd(&uncomp_stream_);
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uncomp_init_ = false;
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}
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first_chunk_ = true;
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}
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void ZLib::Reset() {
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first_chunk_ = true;
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}
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// --------- COMPRESS MODE
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// Initialization method to be called if we hit an error while
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// compressing. On hitting an error, call this method before returning
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// the error.
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void ZLib::CompressErrorInit() {
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deflateEnd(&comp_stream_);
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comp_init_ = false;
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Reset();
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}
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int ZLib::DeflateInit() {
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return deflateInit2(&comp_stream_,
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compression_level_,
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Z_DEFLATED,
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window_bits_,
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mem_level_,
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Z_DEFAULT_STRATEGY);
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}
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int ZLib::CompressInit(Bytef *dest, uLongf *destLen,
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const Bytef *source, uLong *sourceLen) {
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int err;
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comp_stream_.next_in = (Bytef*)source;
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comp_stream_.avail_in = (uInt)*sourceLen;
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if ((uLong)comp_stream_.avail_in != *sourceLen) return Z_BUF_ERROR;
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comp_stream_.next_out = dest;
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comp_stream_.avail_out = (uInt)*destLen;
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if ((uLong)comp_stream_.avail_out != *destLen) return Z_BUF_ERROR;
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if ( !first_chunk_ ) // only need to set up stream the first time through
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return Z_OK;
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if (comp_init_) { // we've already initted it
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err = deflateReset(&comp_stream_);
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if (err != Z_OK) {
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LOG(WARNING) << "ERROR: Can't reset compress object; creating a new one";
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deflateEnd(&comp_stream_);
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comp_init_ = false;
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}
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}
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if (!comp_init_) { // first use
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comp_stream_.zalloc = (alloc_func)0;
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comp_stream_.zfree = (free_func)0;
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comp_stream_.opaque = (voidpf)0;
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err = DeflateInit();
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if (err != Z_OK) return err;
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comp_init_ = true;
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}
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return Z_OK;
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}
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// In a perfect world we'd always have the full buffer to compress
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// when the time came, and we could just call Compress(). Alas, we
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// want to do chunked compression on our webserver. In this
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// application, we compress the header, send it off, then compress the
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// results, send them off, then compress the footer. Thus we need to
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// use the chunked compression features of zlib.
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int ZLib::CompressAtMostOrAll(Bytef *dest, uLongf *destLen,
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const Bytef *source, uLong *sourceLen,
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int flush_mode) { // Z_FULL_FLUSH or Z_FINISH
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int err;
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if ( (err=CompressInit(dest, destLen, source, sourceLen)) != Z_OK )
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return err;
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// This is used to figure out how many bytes we wrote *this chunk*
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int compressed_size = comp_stream_.total_out;
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// Some setup happens only for the first chunk we compress in a run
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if ( first_chunk_ ) {
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first_chunk_ = false;
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}
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// flush_mode is Z_FINISH for all mode, Z_SYNC_FLUSH for incremental
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// compression.
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err = deflate(&comp_stream_, flush_mode);
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const uLong source_bytes_consumed = *sourceLen - comp_stream_.avail_in;
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*sourceLen = comp_stream_.avail_in;
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if ((err == Z_STREAM_END || err == Z_OK)
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&& comp_stream_.avail_in == 0
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&& comp_stream_.avail_out != 0 ) {
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// we processed everything ok and the output buffer was large enough.
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;
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} else if (err == Z_STREAM_END && comp_stream_.avail_in > 0) {
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return Z_BUF_ERROR; // should never happen
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} else if (err != Z_OK && err != Z_STREAM_END && err != Z_BUF_ERROR) {
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// an error happened
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CompressErrorInit();
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return err;
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} else if (comp_stream_.avail_out == 0) { // not enough space
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err = Z_BUF_ERROR;
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}
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assert(err == Z_OK || err == Z_STREAM_END || err == Z_BUF_ERROR);
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if (err == Z_STREAM_END)
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err = Z_OK;
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// update the crc and other metadata
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compressed_size = comp_stream_.total_out - compressed_size; // delta
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*destLen = compressed_size;
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return err;
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}
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int ZLib::CompressChunkOrAll(Bytef *dest, uLongf *destLen,
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const Bytef *source, uLong sourceLen,
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int flush_mode) { // Z_FULL_FLUSH or Z_FINISH
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const int ret =
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CompressAtMostOrAll(dest, destLen, source, &sourceLen, flush_mode);
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if (ret == Z_BUF_ERROR)
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CompressErrorInit();
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return ret;
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}
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// This routine only initializes the compression stream once. Thereafter, it
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// just does a deflateReset on the stream, which should be faster.
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int ZLib::Compress(Bytef *dest, uLongf *destLen,
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const Bytef *source, uLong sourceLen) {
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int err;
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const uLongf orig_destLen = *destLen;
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if ( (err=CompressChunkOrAll(dest, destLen, source, sourceLen,
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Z_FINISH)) != Z_OK )
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return err;
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Reset(); // reset for next call to Compress
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return Z_OK;
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}
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// --------- UNCOMPRESS MODE
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int ZLib::InflateInit() {
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return inflateInit2(&uncomp_stream_, MAX_WBITS);
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}
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// Initialization method to be called if we hit an error while
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// uncompressing. On hitting an error, call this method before
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// returning the error.
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void ZLib::UncompressErrorInit() {
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inflateEnd(&uncomp_stream_);
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uncomp_init_ = false;
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Reset();
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}
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int ZLib::UncompressInit(Bytef *dest, uLongf *destLen,
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const Bytef *source, uLong *sourceLen) {
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int err;
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uncomp_stream_.next_in = (Bytef*)source;
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uncomp_stream_.avail_in = (uInt)*sourceLen;
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// Check for source > 64K on 16-bit machine:
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if ((uLong)uncomp_stream_.avail_in != *sourceLen) return Z_BUF_ERROR;
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uncomp_stream_.next_out = dest;
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uncomp_stream_.avail_out = (uInt)*destLen;
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if ((uLong)uncomp_stream_.avail_out != *destLen) return Z_BUF_ERROR;
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if ( !first_chunk_ ) // only need to set up stream the first time through
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return Z_OK;
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if (uncomp_init_) { // we've already initted it
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err = inflateReset(&uncomp_stream_);
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if (err != Z_OK) {
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LOG(WARNING)
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<< "ERROR: Can't reset uncompress object; creating a new one";
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UncompressErrorInit();
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}
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}
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if (!uncomp_init_) {
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uncomp_stream_.zalloc = (alloc_func)0;
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uncomp_stream_.zfree = (free_func)0;
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uncomp_stream_.opaque = (voidpf)0;
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err = InflateInit();
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if (err != Z_OK) return err;
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uncomp_init_ = true;
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}
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return Z_OK;
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}
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// If you compressed your data a chunk at a time, with CompressChunk,
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// you can uncompress it a chunk at a time with UncompressChunk.
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// Only difference bewteen chunked and unchunked uncompression
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// is the flush mode we use: Z_SYNC_FLUSH (chunked) or Z_FINISH (unchunked).
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int ZLib::UncompressAtMostOrAll(Bytef *dest, uLongf *destLen,
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const Bytef *source, uLong *sourceLen,
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int flush_mode) { // Z_SYNC_FLUSH or Z_FINISH
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int err = Z_OK;
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if ( (err=UncompressInit(dest, destLen, source, sourceLen)) != Z_OK ) {
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LOG(WARNING) << "UncompressInit: Error: " << err << " SourceLen: "
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<< *sourceLen;
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return err;
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}
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// This is used to figure out how many output bytes we wrote *this chunk*:
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const uLong old_total_out = uncomp_stream_.total_out;
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// This is used to figure out how many input bytes we read *this chunk*:
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const uLong old_total_in = uncomp_stream_.total_in;
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// Some setup happens only for the first chunk we compress in a run
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if ( first_chunk_ ) {
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first_chunk_ = false; // so we don't do this again
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// For the first chunk *only* (to avoid infinite troubles), we let
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// there be no actual data to uncompress. This sometimes triggers
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// when the input is only the gzip header, say.
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if ( *sourceLen == 0 ) {
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*destLen = 0;
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return Z_OK;
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}
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}
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// We'll uncompress as much as we can. If we end OK great, otherwise
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// if we get an error that seems to be the gzip footer, we store the
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// gzip footer and return OK, otherwise we return the error.
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// flush_mode is Z_SYNC_FLUSH for chunked mode, Z_FINISH for all mode.
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err = inflate(&uncomp_stream_, flush_mode);
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// Figure out how many bytes of the input zlib slurped up:
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const uLong bytes_read = uncomp_stream_.total_in - old_total_in;
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CHECK_LE(source + bytes_read, source + *sourceLen);
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*sourceLen = uncomp_stream_.avail_in;
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if ((err == Z_STREAM_END || err == Z_OK) // everything went ok
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|
&& uncomp_stream_.avail_in == 0) { // and we read it all
|
|
;
|
|
} else if (err == Z_STREAM_END && uncomp_stream_.avail_in > 0) {
|
|
LOG(WARNING)
|
|
<< "UncompressChunkOrAll: Received some extra data, bytes total: "
|
|
<< uncomp_stream_.avail_in << " bytes: "
|
|
<< string(reinterpret_cast<const char *>(uncomp_stream_.next_in),
|
|
min(int(uncomp_stream_.avail_in), 20));
|
|
UncompressErrorInit();
|
|
return Z_DATA_ERROR; // what's the extra data for?
|
|
} else if (err != Z_OK && err != Z_STREAM_END && err != Z_BUF_ERROR) {
|
|
// an error happened
|
|
LOG(WARNING) << "UncompressChunkOrAll: Error: " << err
|
|
<< " avail_out: " << uncomp_stream_.avail_out;
|
|
UncompressErrorInit();
|
|
return err;
|
|
} else if (uncomp_stream_.avail_out == 0) {
|
|
err = Z_BUF_ERROR;
|
|
}
|
|
|
|
assert(err == Z_OK || err == Z_BUF_ERROR || err == Z_STREAM_END);
|
|
if (err == Z_STREAM_END)
|
|
err = Z_OK;
|
|
|
|
*destLen = uncomp_stream_.total_out - old_total_out; // size for this call
|
|
|
|
return err;
|
|
}
|
|
|
|
int ZLib::UncompressChunkOrAll(Bytef *dest, uLongf *destLen,
|
|
const Bytef *source, uLong sourceLen,
|
|
int flush_mode) { // Z_SYNC_FLUSH or Z_FINISH
|
|
const int ret =
|
|
UncompressAtMostOrAll(dest, destLen, source, &sourceLen, flush_mode);
|
|
if (ret == Z_BUF_ERROR)
|
|
UncompressErrorInit();
|
|
return ret;
|
|
}
|
|
|
|
int ZLib::UncompressAtMost(Bytef *dest, uLongf *destLen,
|
|
const Bytef *source, uLong *sourceLen) {
|
|
return UncompressAtMostOrAll(dest, destLen, source, sourceLen, Z_SYNC_FLUSH);
|
|
}
|
|
|
|
// We make sure we've uncompressed everything, that is, the current
|
|
// uncompress stream is at a compressed-buffer-EOF boundary. In gzip
|
|
// mode, we also check the gzip footer to make sure we pass the gzip
|
|
// consistency checks. We RETURN true iff both types of checks pass.
|
|
bool ZLib::UncompressChunkDone() {
|
|
assert(!first_chunk_ && uncomp_init_);
|
|
// Make sure we're at the end-of-compressed-data point. This means
|
|
// if we call inflate with Z_FINISH we won't consume any input or
|
|
// write any output
|
|
Bytef dummyin, dummyout;
|
|
uLongf dummylen = 0;
|
|
if ( UncompressChunkOrAll(&dummyout, &dummylen, &dummyin, 0, Z_FINISH)
|
|
!= Z_OK ) {
|
|
return false;
|
|
}
|
|
|
|
// Make sure that when we exit, we can start a new round of chunks later
|
|
Reset();
|
|
|
|
return true;
|
|
}
|
|
|
|
// Uncompresses the source buffer into the destination buffer.
|
|
// The destination buffer must be long enough to hold the entire
|
|
// decompressed contents.
|
|
//
|
|
// We only initialize the uncomp_stream once. Thereafter, we use
|
|
// inflateReset, which should be faster.
|
|
//
|
|
// Returns Z_OK on success, otherwise, it returns a zlib error code.
|
|
int ZLib::Uncompress(Bytef *dest, uLongf *destLen,
|
|
const Bytef *source, uLong sourceLen) {
|
|
int err;
|
|
if ( (err=UncompressChunkOrAll(dest, destLen, source, sourceLen,
|
|
Z_FINISH)) != Z_OK ) {
|
|
Reset(); // let us try to compress again
|
|
return err;
|
|
}
|
|
if ( !UncompressChunkDone() ) // calls Reset()
|
|
return Z_DATA_ERROR;
|
|
return Z_OK; // stream_end is ok
|
|
}
|
|
|
|
#endif // HAVE_LIBZ
|
|
|
|
} // namespace snappy
|