debug.cc

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 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
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 * modified or unmodified, in source code or in binary form.
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 * met: redistributions of source code must retain the above copyright
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#include "base/debug.hh"
 
#include <sys/types.h>
#include <unistd.h>
 
#include <algorithm>
#include <csignal>
 
#include "base/cprintf.hh"
#include "base/logging.hh"
 
namespace Debug {
 
//
// This function will cause the process to signal itself with a
// SIGTRAP which is ignored if not in gdb, but will cause the debugger
// to break if in gdb.
//
void
breakpoint()
{
#ifndef NDEBUG
    kill(getpid(), SIGTRAP);
#else
    cprintf("Debug::breakpoint suppressed, compiled with NDEBUG\n");
#endif
}
 
//
// Flags for debugging purposes.  Primarily for trace.hh
//
int allFlagsVersion = 0;
FlagsMap &
allFlags()
{
    static FlagsMap flags;
    return flags;
}
 
bool Flag::_globalEnable = false;
 
Flag *
findFlag(const std::string &name)
{
    FlagsMap::iterator i = allFlags().find(name);
    if (i == allFlags().end())
        return NULL;
    return i->second;
}
 
Flag::Flag(const char *name, const char *desc)
    : _name(name), _desc(desc)
{
    std::pair<FlagsMap::iterator, bool> result =
        allFlags().insert(std::make_pair(name, this));
 
    panic_if(!result.second, "Flag %s already defined!", name);
 
    ++allFlagsVersion;
 
    sync();
}
 
Flag::~Flag()
{
    allFlags().erase(name());
}
 
void
Flag::globalEnable()
{
    _globalEnable = true;
    for (auto& i : allFlags())
        i.second->sync();
}
 
void
Flag::globalDisable()
{
    _globalEnable = false;
    for (auto& i : allFlags())
        i.second->sync();
}
 
void
CompoundFlag::enable()
{
    for (auto& k : _kids)
        k->enable();
}
 
void
CompoundFlag::disable()
{
    for (auto& k : _kids)
        k->disable();
}
 
bool
CompoundFlag::enabled() const
{
    if (_kids.empty())
        return false;
 
    for (auto& k : _kids) {
        if (!k->enabled())
            return false;
    }
 
    return true;
}
 
bool
changeFlag(const char *s, bool value)
{
    Flag *f = findFlag(s);
    if (!f)
        return false;
 
    if (value)
        f->enable();
    else
        f->disable();
 
    return true;
}
 
} // namespace Debug
 
// add a set of functions that can easily be invoked from gdb
void
setDebugFlag(const char *string)
{
    Debug::changeFlag(string, true);
}
 
void
clearDebugFlag(const char *string)
{
    Debug::changeFlag(string, false);
}
 
void
dumpDebugFlags()
{
    using namespace Debug;
    FlagsMap::iterator i = allFlags().begin();
    FlagsMap::iterator end = allFlags().end();
    for (; i != end; ++i) {
        SimpleFlag *f = dynamic_cast<SimpleFlag *>(i->second);
        if (f && f->enabled())
            cprintf("%s\n", f->name());
    }
}