ceph/src/common/cmdparse.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) 2013 Inktank Storage, Inc.
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public
  10  * License version 2, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15 #include "json_spirit/json_spirit.h"
  16 #include "common/debug.h"
  17
  18 using namespace std;
  19
  20 /**
  21  * Given a cmddesc like "foo baz name=bar,type=CephString",
  22  * return the prefix "foo baz".
  23  */
  24 std::string cmddesc_get_prefix(const std::string &cmddesc)
  25 {
  26   stringstream ss(cmddesc);
  27   std::string word;
  28   std::ostringstream result;
  29   bool first = true;
  30   while (std::getline(ss, word, ' ')) {
  31     if (word.find_first_of(",=") != string::npos) {
  32       break;
  33     }
  34
  35     if (!first) {
  36       result << " ";
  37     }
  38     result << word;
  39     first = false;
  40   }
  41
  42   return result.str();
  43 }
  44
  45 /**
  46  * Read a command description list out of cmd, and dump it to f.
  47  * A signature description is a set of space-separated words;
  48  * see MonCommands.h for more info.
  49  */
  50
  51 void
  52 dump_cmd_to_json(Formatter *f, const string& cmd)
  53 {
  54   // put whole command signature in an already-opened container
  55   // elements are: "name", meaning "the typeless name that means a literal"
  56   // an object {} with key:value pairs representing an argument
  57
  58   int argnum = 0;
  59   stringstream ss(cmd);
  60   std::string word;
  61
  62   while (std::getline(ss, word, ' ')) {
  63     argnum++;
  64     // if no , or =, must be a plain word to put out
  65     if (word.find_first_of(",=") == string::npos) {
  66       f->dump_string("arg", word);
  67       continue;
  68     }
  69     // Snarf up all the key=val,key=val pairs, put 'em in a dict.
  70     // no '=val' implies '=True'.
  71     std::stringstream argdesc(word);
  72     std::string keyval;
  73     std::map<std::string, std::string>desckv;
  74     // accumulate descriptor keywords in desckv
  75
  76     while (std::getline(argdesc, keyval, ',')) {
  77       // key=value; key by itself implies value is bool true
  78       // name="name" means arg dict will be titled 'name'
  79       size_t pos = keyval.find('=');
  80       std::string key, val;
  81       if (pos != std::string::npos) {
  82         key = keyval.substr(0, pos);
  83         val = keyval.substr(pos+1);
  84       } else {
  85         key = keyval;
  86         val = true;
  87       }
  88       desckv.insert(std::pair<std::string, std::string> (key, val));
  89     }
  90     // name the individual desc object based on the name key
  91     f->open_object_section(desckv["name"].c_str());
  92     // dump all the keys including name into the array
  93     for (std::map<std::string, std::string>::iterator it = desckv.begin();
  94          it != desckv.end(); ++it) {
  95       f->dump_string(it->first.c_str(), it->second);
  96     }
  97     f->close_section(); // attribute object for individual desc
  98   }
  99 }
 100
 101 void
 102 dump_cmd_and_help_to_json(Formatter *jf,
 103                           const string& secname,
 104                           const string& cmdsig,
 105                           const string& helptext)
 106 {
 107       jf->open_object_section(secname.c_str());
 108       jf->open_array_section("sig");
 109       dump_cmd_to_json(jf, cmdsig);
 110       jf->close_section(); // sig array
 111       jf->dump_string("help", helptext.c_str());
 112       jf->close_section(); // cmd
 113 }
 114
 115 void
 116 dump_cmddesc_to_json(Formatter *jf,
 117                      const string& secname,
 118                      const string& cmdsig,
 119                      const string& helptext,
 120                      const string& module,
 121                      const string& perm,
 122                      const string& avail,
 123                      uint64_t flags)
 124 {
 125       jf->open_object_section(secname.c_str());
 126       jf->open_array_section("sig");
 127       dump_cmd_to_json(jf, cmdsig);
 128       jf->close_section(); // sig array
 129       jf->dump_string("help", helptext.c_str());
 130       jf->dump_string("module", module.c_str());
 131       jf->dump_string("perm", perm.c_str());
 132       jf->dump_string("avail", avail.c_str());
 133       jf->dump_int("flags", flags);
 134       jf->close_section(); // cmd
 135 }
 136
 137 void cmdmap_dump(const cmdmap_t &cmdmap, Formatter *f)
 138 {
 139   assert(f != nullptr);
 140
 141   class dump_visitor : public boost::static_visitor<void>
 142   {
 143     Formatter *f;
 144     std::string const &key;
 145     public:
 146     dump_visitor(Formatter *f_, std::string const &key_)
 147       : f(f_), key(key_)
 148     {
 149     }
 150
 151     void operator()(const std::string &operand) const
 152     {
 153       f->dump_string(key.c_str(), operand);
 154     }
 155
 156     void operator()(const bool &operand) const
 157     {
 158       f->dump_bool(key.c_str(), operand);
 159     }
 160
 161     void operator()(const int64_t &operand) const
 162     {
 163       f->dump_int(key.c_str(), operand);
 164     }
 165
 166     void operator()(const double &operand) const
 167     {
 168       f->dump_float(key.c_str(), operand);
 169     }
 170
 171     void operator()(const std::vector<std::string> &operand) const
 172     {
 173       f->open_array_section(key.c_str());
 174       for (const auto i : operand) {
 175         f->dump_string("item", i);
 176       }
 177       f->close_section();
 178     }
 179
 180     void operator()(const std::vector<int64_t> &operand) const
 181     {
 182       f->open_array_section(key.c_str());
 183       for (const auto i : operand) {
 184         f->dump_int("item", i);
 185       }
 186       f->close_section();
 187     }
 188   };
 189
 190   //f->open_object_section("cmdmap");
 191   for (const auto &i : cmdmap) {
 192     boost::apply_visitor(dump_visitor(f, i.first), i.second);
 193   }
 194   //f->close_section();
 195 }
 196
 197
 198 /** Parse JSON in vector cmd into a map from field to map of values
 199  * (use mValue/mObject)
 200  * 'cmd' should not disappear over lifetime of map
 201  * 'mapp' points to the caller's map
 202  * 'ss' captures any errors during JSON parsing; if function returns
 203  * false, ss is valid */
 204
 205 bool
 206 cmdmap_from_json(vector<string> cmd, map<string, cmd_vartype> *mapp, stringstream &ss)
 207 {
 208   json_spirit::mValue v;
 209
 210   string fullcmd;
 211   // First, join all cmd strings
 212   for (vector<string>::iterator it = cmd.begin();
 213        it != cmd.end(); ++it)
 214     fullcmd += *it;
 215
 216   try {
 217     if (!json_spirit::read(fullcmd, v))
 218       throw runtime_error("unparseable JSON " + fullcmd);
 219     if (v.type() != json_spirit::obj_type)
 220       throw(runtime_error("not JSON object " + fullcmd));
 221
 222     // allocate new mObject (map) to return
 223     // make sure all contents are simple types (not arrays or objects)
 224     json_spirit::mObject o = v.get_obj();
 225     for (map<string, json_spirit::mValue>::iterator it = o.begin();
 226          it != o.end(); ++it) {
 227
 228       // ok, marshal it into our string->cmd_vartype map, or throw an
 229       // exception if it's not a simple datatype.  This is kind of
 230       // annoying, since json_spirit has a boost::variant inside it
 231       // already, but it's not public.  Oh well.
 232
 233       switch (it->second.type()) {
 234
 235       case json_spirit::obj_type:
 236       default:
 237         throw(runtime_error("JSON array/object not allowed " + fullcmd));
 238         break;
 239
 240       case json_spirit::array_type:
 241         {
 242           // array is a vector of values.  Unpack it to a vector
 243           // of strings or int64_t, the only types we handle.
 244           const vector<json_spirit::mValue>& spvals = it->second.get_array();
 245           if (spvals.empty()) {
 246             // if an empty array is acceptable, the caller should always check for
 247             // vector<string> if the expected value of "vector<int64_t>" in the
 248             // cmdmap is missing.
 249             (*mapp)[it->first] = vector<string>();
 250           } else if (spvals.front().type() == json_spirit::str_type) {
 251             vector<string> outv;
 252             for (const auto& sv : spvals) {
 253               if (sv.type() != json_spirit::str_type) {
 254                 throw(runtime_error("Can't handle arrays of multiple types"));
 255               }
 256               outv.push_back(sv.get_str());
 257             }
 258             (*mapp)[it->first] = std::move(outv);
 259           } else if (spvals.front().type() == json_spirit::int_type) {
 260             vector<int64_t> outv;
 261             for (const auto& sv : spvals) {
 262               if (spvals.front().type() != json_spirit::int_type) {
 263                 throw(runtime_error("Can't handle arrays of multiple types"));
 264               }
 265               outv.push_back(sv.get_int64());
 266             }
 267             (*mapp)[it->first] = std::move(outv);
 268           } else {
 269             throw(runtime_error("Can't handle arrays of types other than "
 270                                 "int or string"));
 271           }
 272         }
 273         break;
 274       case json_spirit::str_type:
 275         (*mapp)[it->first] = it->second.get_str();
 276         break;
 277
 278       case json_spirit::bool_type:
 279         (*mapp)[it->first] = it->second.get_bool();
 280         break;
 281
 282       case json_spirit::int_type:
 283         (*mapp)[it->first] = it->second.get_int64();
 284         break;
 285
 286       case json_spirit::real_type:
 287         (*mapp)[it->first] = it->second.get_real();
 288         break;
 289       }
 290     }
 291     return true;
 292   } catch (runtime_error &e) {
 293     ss << e.what();
 294     return false;
 295   }
 296 }
 297
 298 class stringify_visitor : public boost::static_visitor<string>
 299 {
 300   public:
 301     template <typename T>
 302     string operator()(T &operand) const
 303       {
 304         ostringstream oss;
 305         oss << operand;
 306         return oss.str();
 307       }
 308 };
 309
 310 string
 311 cmd_vartype_stringify(const cmd_vartype &v)
 312 {
 313   return boost::apply_visitor(stringify_visitor(), v);
 314 }
 315
 316
 317 void
 318 handle_bad_get(CephContext *cct, const string& k, const char *tname)
 319 {
 320   ostringstream errstr;
 321   int status;
 322   const char *typestr = abi::__cxa_demangle(tname, 0, 0, &status);
 323   if (status != 0)
 324     typestr = tname;
 325   errstr << "bad boost::get: key " << k << " is not type " << typestr;
 326   lderr(cct) << errstr.str() << dendl;
 327
 328   ostringstream oss;
 329   oss << BackTrace(1);
 330   lderr(cct) << oss.rdbuf() << dendl;
 331   if (status == 0)
 332     free((char *)typestr);
 333 }
 334
 335 long parse_pos_long(const char *s, std::ostream *pss)
 336 {
 337   if (*s == '-' || *s == '+') {
 338     if (pss)
 339       *pss << "expected numerical value, got: " << s;
 340     return -EINVAL;
 341   }
 342
 343   string err;
 344   long r = strict_strtol(s, 10, &err);
 345   if ((r == 0) && !err.empty()) {
 346     if (pss)
 347       *pss << err;
 348     return -1;
 349   }
 350   if (r < 0) {
 351     if (pss)
 352       *pss << "unable to parse positive integer '" << s << "'";
 353     return -1;
 354   }
 355   return r;
 356 }
 357
 358 int parse_osd_id(const char *s, std::ostream *pss)
 359 {
 360   // osd.NNN?
 361   if (strncmp(s, "osd.", 4) == 0) {
 362     s += 4;
 363   }
 364
 365   // NNN?
 366   ostringstream ss;
 367   long id = parse_pos_long(s, &ss);
 368   if (id < 0) {
 369     *pss << ss.str();
 370     return id;
 371   }
 372   if (id > 0xffff) {
 373     *pss << "osd id " << id << " is too large";
 374     return -ERANGE;
 375   }
 376   return id;
 377 }