src/base/debug.cc

   1 /*
   2  * Copyright (c) 2003-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "base/debug.hh"
  30
  31 #include <sys/types.h>
  32 #include <unistd.h>
  33
  34 #include <algorithm>
  35 #include <csignal>
  36
  37 #include "base/cprintf.hh"
  38 #include "base/logging.hh"
  39
  40 using namespace std;
  41
  42 namespace Debug {
  43
  44 //
  45 // This function will cause the process to signal itself with a
  46 // SIGTRAP which is ignored if not in gdb, but will cause the debugger
  47 // to break if in gdb.
  48 //
  49 void
  50 breakpoint()
  51 {
  52 #ifndef NDEBUG
  53     kill(getpid(), SIGTRAP);
  54 #else
  55     cprintf("Debug::breakpoint suppressed, compiled with NDEBUG\n");
  56 #endif
  57 }
  58
  59 //
  60 // Flags for debugging purposes.  Primarily for trace.hh
  61 //
  62 int allFlagsVersion = 0;
  63 FlagsMap &
  64 allFlags()
  65 {
  66     static FlagsMap flags;
  67     return flags;
  68 }
  69
  70 bool SimpleFlag::_active = false;
  71
  72 Flag *
  73 findFlag(const std::string &name)
  74 {
  75     FlagsMap::iterator i = allFlags().find(name);
  76     if (i == allFlags().end())
  77         return NULL;
  78     return i->second;
  79 }
  80
  81 Flag::Flag(const char *name, const char *desc)
  82     : _name(name), _desc(desc)
  83 {
  84     pair<FlagsMap::iterator, bool> result =
  85         allFlags().insert(make_pair(name, this));
  86
  87     if (!result.second)
  88         panic("Flag %s already defined!", name);
  89
  90     ++allFlagsVersion;
  91 }
  92
  93 Flag::~Flag()
  94 {
  95     // should find and remove flag.
  96 }
  97
  98 void
  99 SimpleFlag::enableAll()
 100 {
 101     _active = true;
 102     for (auto& i : allFlags())
 103         i.second->sync();
 104 }
 105
 106 void
 107 SimpleFlag::disableAll()
 108 {
 109     _active = false;
 110     for (auto& i : allFlags())
 111         i.second->sync();
 112 }
 113
 114 void
 115 CompoundFlag::enable()
 116 {
 117     for (auto& k : _kids)
 118         k->enable();
 119 }
 120
 121 void
 122 CompoundFlag::disable()
 123 {
 124     for (auto& k : _kids)
 125         k->disable();
 126 }
 127
 128 struct AllFlags : public Flag
 129 {
 130     AllFlags()
 131         : Flag("All", "All Flags")
 132     {}
 133
 134     void
 135     enable()
 136     {
 137         FlagsMap::iterator i = allFlags().begin();
 138         FlagsMap::iterator end = allFlags().end();
 139         for (; i != end; ++i)
 140             if (i->second != this)
 141                 i->second->enable();
 142     }
 143
 144     void
 145     disable()
 146     {
 147         FlagsMap::iterator i = allFlags().begin();
 148         FlagsMap::iterator end = allFlags().end();
 149         for (; i != end; ++i)
 150             if (i->second != this)
 151                 i->second->disable();
 152     }
 153 };
 154
 155 AllFlags theAllFlags;
 156 Flag *const All = &theAllFlags;
 157
 158 bool
 159 changeFlag(const char *s, bool value)
 160 {
 161     Flag *f = findFlag(s);
 162     if (!f)
 163         return false;
 164
 165     if (value)
 166         f->enable();
 167     else
 168         f->disable();
 169
 170     return true;
 171 }
 172
 173 } // namespace Debug
 174
 175 // add a set of functions that can easily be invoked from gdb
 176 void
 177 setDebugFlag(const char *string)
 178 {
 179     Debug::changeFlag(string, true);
 180 }
 181
 182 void
 183 clearDebugFlag(const char *string)
 184 {
 185     Debug::changeFlag(string, false);
 186 }
 187
 188 void
 189 dumpDebugFlags()
 190 {
 191     using namespace Debug;
 192     FlagsMap::iterator i = allFlags().begin();
 193     FlagsMap::iterator end = allFlags().end();
 194     for (; i != end; ++i) {
 195         SimpleFlag *f = dynamic_cast<SimpleFlag *>(i->second);
 196         if (f && f->status())
 197             cprintf("%s\n", f->name());
 198     }
 199 }