ceph/src/compressor/Compressor.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2014 Haomai Wang <haomaiwang@gmail.com>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15 #include <random>
  16 #include <sstream>
  17
  18 #include "CompressionPlugin.h"
  19 #include "Compressor.h"
  20 #include "common/ceph_context.h"
  21 #include "common/debug.h"
  22 #include "common/dout.h"
  23
  24 const char * Compressor::get_comp_alg_name(int a) {
  25   switch (a) {
  26   case COMP_ALG_NONE: return "none";
  27   case COMP_ALG_SNAPPY: return "snappy";
  28   case COMP_ALG_ZLIB: return "zlib";
  29   case COMP_ALG_ZSTD: return "zstd";
  30 #ifdef HAVE_LZ4
  31   case COMP_ALG_LZ4: return "lz4";
  32 #endif
  33   default: return "???";
  34   }
  35 }
  36
  37 boost::optional<Compressor::CompressionAlgorithm> Compressor::get_comp_alg_type(const std::string &s) {
  38   if (s == "snappy")
  39     return COMP_ALG_SNAPPY;
  40   if (s == "zlib")
  41     return COMP_ALG_ZLIB;
  42   if (s == "zstd")
  43     return COMP_ALG_ZSTD;
  44 #ifdef HAVE_LZ4
  45   if (s == "lz4")
  46     return COMP_ALG_LZ4;
  47 #endif
  48   if (s == "" || s == "none")
  49     return COMP_ALG_NONE;
  50
  51   return boost::optional<CompressionAlgorithm>();
  52 }
  53
  54 const char *Compressor::get_comp_mode_name(int m) {
  55   switch (m) {
  56     case COMP_NONE: return "none";
  57     case COMP_PASSIVE: return "passive";
  58     case COMP_AGGRESSIVE: return "aggressive";
  59     case COMP_FORCE: return "force";
  60     default: return "???";
  61   }
  62 }
  63 boost::optional<Compressor::CompressionMode> Compressor::get_comp_mode_type(const std::string &s) {
  64   if (s == "force")
  65     return COMP_FORCE;
  66   if (s == "aggressive")
  67     return COMP_AGGRESSIVE;
  68   if (s == "passive")
  69     return COMP_PASSIVE;
  70   if (s == "none")
  71     return COMP_NONE;
  72   return boost::optional<CompressionMode>();
  73 }
  74
  75 CompressorRef Compressor::create(CephContext *cct, const std::string &type)
  76 {
  77   // support "random" for teuthology testing
  78   if (type == "random") {
  79     static std::random_device seed;
  80     static std::default_random_engine engine(seed());
  81     static Spinlock mutex;
  82
  83     int alg = COMP_ALG_NONE;
  84     std::uniform_int_distribution<> dist(0, COMP_ALG_LAST - 1);
  85     {
  86       std::lock_guard<Spinlock> lock(mutex);
  87       alg = dist(engine);
  88     }
  89     if (alg == COMP_ALG_NONE) {
  90       return nullptr;
  91     }
  92     return create(cct, alg);
  93   }
  94
  95   CompressorRef cs_impl = NULL;
  96   std::stringstream ss;
  97   PluginRegistry *reg = cct->get_plugin_registry();
  98   CompressionPlugin *factory = dynamic_cast<CompressionPlugin*>(reg->get_with_load("compressor", type));
  99   if (factory == NULL) {
 100     lderr(cct) << __func__ << " cannot load compressor of type " << type << dendl;
 101     return NULL;
 102   }
 103   int err = factory->factory(&cs_impl, &ss);
 104   if (err)
 105     lderr(cct) << __func__ << " factory return error " << err << dendl;
 106   return cs_impl;
 107 }
 108
 109 CompressorRef Compressor::create(CephContext *cct, int alg)
 110 {
 111   if (alg < 0 || alg >= COMP_ALG_LAST) {
 112     lderr(cct) << __func__ << " invalid algorithm value:" << alg << dendl;
 113     return CompressorRef();
 114   }
 115   std::string type_name = get_comp_alg_name(alg);
 116   return create(cct, type_name);
 117 }