src/misc/dbg_helpers.h

   1 /* $Id: dbg_helpers.h 20603 2010-08-23 22:03:36Z rubidium $ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   6  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   7  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   8  */
   9
  10 /** @file dbg_helpers.h Functions to be used for debug printings. */
  11
  12 #ifndef DBG_HELPERS_H
  13 #define DBG_HELPERS_H
  14
  15 #include <map>
  16 #include <stack>
  17
  18 #include "str.hpp"
  19
  20 #include "../direction_type.h"
  21 #include "../signal_type.h"
  22 #include "../tile_type.h"
  23 #include "../track_type.h"
  24
  25 /** Helper template class that provides C array length and item type */
  26 template <typename T> struct ArrayT;
  27
  28 /** Helper template class that provides C array length and item type */
  29 template <typename T, size_t N> struct ArrayT<T[N]> {
  30         static const size_t length = N;
  31         typedef T item_t;
  32 };
  33
  34
  35 /**
  36  * Helper template function that returns item of array at given index
  37  * or t_unk when index is out of bounds.
  38  */
  39 template <typename E, typename T>
  40 inline typename ArrayT<T>::item_t ItemAtT(E idx, const T &t, typename ArrayT<T>::item_t t_unk)
  41 {
  42         if ((size_t)idx >= ArrayT<T>::length) {
  43                 return t_unk;
  44         }
  45         return t[idx];
  46 }
  47
  48 /**
  49  * Helper template function that returns item of array at given index
  50  * or t_inv when index == idx_inv
  51  * or t_unk when index is out of bounds.
  52  */
  53 template <typename E, typename T>
  54 inline typename ArrayT<T>::item_t ItemAtT(E idx, const T &t, typename ArrayT<T>::item_t t_unk, E idx_inv, typename ArrayT<T>::item_t t_inv)
  55 {
  56         if ((size_t)idx < ArrayT<T>::length) {
  57                 return t[idx];
  58         }
  59         if (idx == idx_inv) {
  60                 return t_inv;
  61         }
  62         return t_unk;
  63 }
  64
  65 /**
  66  * Helper template function that returns compound bitfield name that is
  67  * concatenation of names of each set bit in the given value
  68  * or t_inv when index == idx_inv
  69  * or t_unk when index is out of bounds.
  70  */
  71 template <typename E, typename T>
  72 inline CStrA ComposeNameT(E value, T &t, const char *t_unk, E val_inv, const char *name_inv)
  73 {
  74         CStrA out;
  75         if (value == val_inv) {
  76                 out = name_inv;
  77         } else if (value == 0) {
  78                 out = "<none>";
  79         } else {
  80                 for (size_t i = 0; i < ArrayT<T>::length; i++) {
  81                         if ((value & (1 << i)) == 0) continue;
  82                         out.AddFormat("%s%s", (out.Size() > 0 ? "+" : ""), (const char*)t[i]);
  83                         value &= ~(E)(1 << i);
  84                 }
  85                 if (value != 0) out.AddFormat("%s%s", (out.Size() > 0 ? "+" : ""), t_unk);
  86         }
  87         return out.Transfer();
  88 }
  89
  90 CStrA ValueStr(Trackdir td);
  91 CStrA ValueStr(TrackdirBits td_bits);
  92 CStrA ValueStr(DiagDirection dd);
  93 CStrA ValueStr(SignalType t);
  94
  95 /** Class that represents the dump-into-string target. */
  96 struct DumpTarget {
  97
  98         /** Used as a key into map of known object instances. */
  99         struct KnownStructKey {
 100                 size_t      m_type_id;
 101                 const void *m_ptr;
 102
 103                 KnownStructKey(size_t type_id, const void *ptr)
 104                         : m_type_id(type_id)
 105                         , m_ptr(ptr)
 106                 {}
 107
 108                 KnownStructKey(const KnownStructKey &src)
 109                 {
 110                         m_type_id = src.m_type_id;
 111                         m_ptr = src.m_ptr;
 112                 }
 113
 114                 bool operator<(const KnownStructKey &other) const
 115                 {
 116                         if ((size_t)m_ptr < (size_t)other.m_ptr) return true;
 117                         if ((size_t)m_ptr > (size_t)other.m_ptr) return false;
 118                         if (m_type_id < other.m_type_id) return true;
 119                         return false;
 120                 }
 121         };
 122
 123         typedef std::map<KnownStructKey, CStrA> KNOWN_NAMES;
 124
 125         CStrA              m_out;         ///< the output string
 126         int                m_indent;      ///< current indent/nesting level
 127         std::stack<CStrA>  m_cur_struct;  ///< here we will track the current structure name
 128         KNOWN_NAMES        m_known_names; ///< map of known object instances and their structured names
 129
 130         DumpTarget()
 131                 : m_indent(0)
 132         {}
 133
 134         static size_t& LastTypeId();
 135         CStrA GetCurrentStructName();
 136         bool FindKnownName(size_t type_id, const void *ptr, CStrA &name);
 137
 138         void WriteIndent();
 139
 140         void CDECL WriteLine(const char *format, ...) WARN_FORMAT(2, 3);
 141         void WriteValue(const char *name, const char *value_str);
 142         void WriteTile(const char *name, TileIndex t);
 143
 144         /** Dump given enum value (as a number and as named value) */
 145         template <typename E> void WriteEnumT(const char *name, E e)
 146         {
 147                 WriteValue(name, ValueStr(e).Data());
 148         }
 149
 150         void BeginStruct(size_t type_id, const char *name, const void *ptr);
 151         void EndStruct();
 152
 153         /** Dump nested object (or only its name if this instance is already known). */
 154         template <typename S> void WriteStructT(const char *name, const S *s)
 155         {
 156                 static size_t type_id = ++LastTypeId();
 157
 158                 if (s == nullptr) {
 159                         /* No need to dump nullptr struct. */
 160                         WriteLine("%s = <null>", name);
 161                         return;
 162                 }
 163                 CStrA known_as;
 164                 if (FindKnownName(type_id, s, known_as)) {
 165                         /* We already know this one, no need to dump it. */
 166                         WriteLine("%s = known_as.%s", name, known_as.Data());
 167                 } else {
 168                         /* Still unknown, dump it */
 169                         BeginStruct(type_id, name, s);
 170                         s->Dump(*this);
 171                         EndStruct();
 172                 }
 173         }
 174 };
 175
 176 #endif /* DBG_HELPERS_H */