xapian-core/common/pretty.h

   1 /** @file
   2  * @brief Convert types to pretty representations
   3  */
   4 /* Copyright (C) 2010,2011,2012,2014,2016 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef XAPIAN_INCLUDED_PRETTY_H
  22 #define XAPIAN_INCLUDED_PRETTY_H
  23
  24 #include <list>
  25 #include <map>
  26 #include <ostream>
  27 #include <string>
  28 #include <vector>
  29
  30 #include "xapian/intrusive_ptr.h"
  31 #include "xapian/types.h"
  32
  33 template<class S>
  34 struct PrettyOStream {
  35     /// The std::ostream object we're outputting to.
  36     S & os;
  37
  38     PrettyOStream(S & os_) : os(os_) { }
  39     template<typename T> PrettyOStream & operator|(const T & t) {
  40         os << ", ";
  41         return *this << t;
  42     }
  43 };
  44
  45 struct Literal {
  46     const char * _lit;
  47     explicit Literal(const char * lit) : _lit(lit) { }
  48     explicit Literal(const std::string & s) : _lit(s.c_str()) { }
  49 };
  50
  51 /// Default is to output as std::ostream would.
  52 template<class S, class T>
  53 inline PrettyOStream<S> &
  54 operator<<(PrettyOStream<S> &ps, const T & t)
  55 {
  56     ps.os << t;
  57     return ps;
  58 }
  59
  60 /** Allow writing literal strings.
  61  *
  62  *  For example:
  63  *
  64  *  PrettyOStream<std::ostream> ps(std::cout);
  65  *  ps << Literal("x = ") << x << Literal(", y = ") << y << endl;
  66  */
  67 template<class S>
  68 inline PrettyOStream<S> &
  69 operator<<(PrettyOStream<S> &ps, const Literal & t)
  70 {
  71     ps.os << t._lit;
  72     return ps;
  73 }
  74
  75 template<class S, class T>
  76 inline PrettyOStream<S> &
  77 operator<<(PrettyOStream<S> &ps, const T * t)
  78 {
  79     if (!t) {
  80         ps.os << "NULL";
  81         return ps;
  82     }
  83     ps.os << '&';
  84     return ps << *t;
  85 }
  86
  87 template<class S, class T>
  88 inline PrettyOStream<S> &
  89 operator<<(PrettyOStream<S> &ps, const T ** t)
  90 {
  91     ps.os << (void*)t;
  92     return ps;
  93 }
  94
  95 template<class S>
  96 inline PrettyOStream<S> &
  97 operator<<(PrettyOStream<S> &ps, const void * t)
  98 {
  99     ps.os << "(void*)" << t;
 100     return ps;
 101 }
 102
 103 // FIXME: We probably don't want to inline this, but need to arrange to
 104 // put it somewhere sane out-of-line.
 105 inline void write_ch(std::ostream & os, unsigned char ch)
 106 {
 107     if (ch < 32 || ch >= 127) {
 108         os << '\\';
 109         if (ch >= 7 && ch <= 13) {
 110             os << "abtnvfr"[ch - 7];
 111         } else {
 112             os << char('0' | (ch >> 6));
 113             os << char('0' | ((ch >> 3) & 7));
 114             os << char('0' | (ch & 7));
 115         }
 116     } else if (ch == '\\') {
 117         os << "\\\\";
 118     } else if (ch == '"') {
 119         os << "\\\"";
 120     } else {
 121         os << ch;
 122     }
 123 }
 124
 125 template<class S>
 126 inline PrettyOStream<S> &
 127 operator<<(PrettyOStream<S> &ps, const char * str)
 128 {
 129     ps.os << '"';
 130     while (*str) {
 131         write_ch(ps.os, *str++);
 132     }
 133     ps.os << '"';
 134     return ps;
 135 }
 136
 137 template<class S>
 138 inline PrettyOStream<S> &
 139 operator<<(PrettyOStream<S> &ps, const std::string & str)
 140 {
 141     ps.os << '"';
 142     for (std::string::const_iterator i = str.begin(); i != str.end(); ++i) {
 143         write_ch(ps.os, *i);
 144     }
 145     ps.os << '"';
 146     return ps;
 147 }
 148
 149 template<class S>
 150 inline PrettyOStream<S> &
 151 operator<<(PrettyOStream<S> &ps, std::string &)
 152 {
 153     ps.os << "std::string&";
 154     return ps;
 155 }
 156
 157 template<class S>
 158 inline PrettyOStream<S> &
 159 operator<<(PrettyOStream<S> &ps, std::string *)
 160 {
 161     ps.os << "std::string*";
 162     return ps;
 163 }
 164
 165 template<class S>
 166 inline PrettyOStream<S> &
 167 operator<<(PrettyOStream<S> &ps, unsigned char ch)
 168 {
 169     ps.os << '\'';
 170     if (ch < 32 || ch >= 127) {
 171         ps.os << '\\';
 172         if (ch >= 7 && ch <= 13) {
 173             ps.os << "abtnvfr"[ch - 7];
 174         } else if (ch == '\0') {
 175             ps.os << "\\0";
 176         } else {
 177             ps.os << "0123456789abcdef"[ch >> 4];
 178             ps.os << "0123456789abcdef"[ch & 0x0f];
 179         }
 180     } else if (ch == '\\') {
 181         ps.os << "\\\\";
 182     } else if (ch == '\'') {
 183         ps.os << "\\'";
 184     } else {
 185         ps.os << ch;
 186     }
 187     ps.os << '\'';
 188     return ps;
 189 }
 190
 191 template<class S>
 192 inline PrettyOStream<S> &
 193 operator<<(PrettyOStream<S> &ps, bool b)
 194 {
 195     ps.os << (b ? "true" : "false");
 196     return ps;
 197 }
 198
 199 /*
 200 template<class S>
 201 inline PrettyOStream<S> &
 202 operator<<(PrettyOStream<S> &ps, bool &)
 203 {
 204     ps.os << "bool&";
 205     return ps;
 206 }
 207 */
 208
 209 template<class S>
 210 inline PrettyOStream<S> &
 211 operator<<(PrettyOStream<S> &ps, Xapian::termcount * p)
 212 {
 213     ps.os << "(Xapian::termcount*)" << (void*)p;
 214     return ps;
 215 }
 216
 217 template<class S, typename T>
 218 inline PrettyOStream<S> &
 219 operator<<(PrettyOStream<S> &ps, std::list<T> &) {
 220     ps.os << "std::list&";
 221     return ps;
 222 }
 223
 224 template<class S, typename T>
 225 inline PrettyOStream<S> &
 226 operator<<(PrettyOStream<S> &ps, const std::list<T> &) {
 227     ps.os << "std::list";
 228     // FIXME: could show first up to N elements.
 229     return ps;
 230 }
 231
 232 template<class S, typename K, typename V>
 233 inline PrettyOStream<S> &
 234 operator<<(PrettyOStream<S> &ps, std::map<K, V> *) {
 235     ps.os << "std::map*";
 236     return ps;
 237 }
 238
 239 template<class S, typename K, typename V>
 240 inline PrettyOStream<S> &
 241 operator<<(PrettyOStream<S> &ps, std::map<K, V> &) {
 242     ps.os << "std::map&";
 243     return ps;
 244 }
 245
 246 template<class S, typename K, typename V>
 247 inline PrettyOStream<S> &
 248 operator<<(PrettyOStream<S> &ps, const std::map<K, V> & m) {
 249     ps.os << "std::map(" << m.size() << ')';
 250     // FIXME: could show first up to N elements.
 251     return ps;
 252 }
 253
 254 template<class S, typename T>
 255 inline PrettyOStream<S> &
 256 operator<<(PrettyOStream<S> &ps, const std::vector<T> & v) {
 257     ps.os << "std::vector(" << v.size() << ')';
 258     // FIXME: could show first up to N elements.
 259     return ps;
 260 }
 261
 262 namespace Xapian {
 263     class ExpandDecider;
 264     class LatLongMetric;
 265     class MatchDecider;
 266     class Registry;
 267     class Weight;
 268     namespace Internal {
 269         class AndContext;
 270         class ExpandStats;
 271         class ExpandWeight;
 272         class OrContext;
 273     }
 274 }
 275
 276 namespace Glass {
 277     class RootInfo;
 278 }
 279
 280 class ChertCursor;
 281 class ChertDatabase;
 282 class ChertTable;
 283 class GlassCursor;
 284 class GlassDatabase;
 285 class GlassFreeListChecker;
 286 class GlassTable;
 287
 288 #define XAPIAN_PRETTY_AS_CLASSNAME(C)\
 289 template<class S>\
 290 inline PrettyOStream<S> &\
 291 operator<<(PrettyOStream<S> &ps, const C &) {\
 292     ps.os << #C;\
 293     return ps;\
 294 }
 295
 296 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::ExpandDecider)
 297 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::LatLongMetric)
 298 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::MatchDecider)
 299 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::Registry)
 300 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::Weight)
 301 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::Internal::AndContext)
 302 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::Internal::ExpandStats)
 303 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::Internal::ExpandWeight)
 304 XAPIAN_PRETTY_AS_CLASSNAME(Xapian::Internal::OrContext)
 305 XAPIAN_PRETTY_AS_CLASSNAME(ChertCursor)
 306 XAPIAN_PRETTY_AS_CLASSNAME(ChertDatabase)
 307 XAPIAN_PRETTY_AS_CLASSNAME(ChertTable)
 308 XAPIAN_PRETTY_AS_CLASSNAME(Glass::RootInfo)
 309 XAPIAN_PRETTY_AS_CLASSNAME(GlassCursor)
 310 XAPIAN_PRETTY_AS_CLASSNAME(GlassFreeListChecker)
 311 XAPIAN_PRETTY_AS_CLASSNAME(GlassDatabase)
 312 XAPIAN_PRETTY_AS_CLASSNAME(GlassTable)
 313
 314 template<class S>
 315 inline PrettyOStream<S> &
 316 operator<<(PrettyOStream<S> &ps, const Xapian::Weight *p) {
 317     ps.os << "(Xapian:Weight*)" << (const void*)p;
 318     return ps;
 319 }
 320
 321 class RemoteConnection;
 322
 323 template<class S>
 324 inline PrettyOStream<S> &
 325 operator<<(PrettyOStream<S> &ps, const RemoteConnection &) {
 326     ps.os << "RemoteConnection";
 327     return ps;
 328 }
 329
 330 #include "backends/database.h"
 331
 332 template<class S>
 333 inline PrettyOStream<S> &
 334 operator<<(PrettyOStream<S> &ps, const Xapian::Database::Internal *p) {
 335     ps.os << "(Database::Internal*)" << (const void*)p;
 336     return ps;
 337 }
 338
 339 template<class S, class T>
 340 inline PrettyOStream<S> &
 341 operator<<(PrettyOStream<S> &ps, Xapian::Internal::intrusive_ptr<const T> t) {
 342     ps.os << "intrusive_ptr->";
 343     return ps << t;
 344 }
 345
 346 #endif // XAPIAN_INCLUDED_PRETTY_H