trap.h
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// trap.h - written and placed in public domain by Jeffrey Walton.
/// \file trap.h
/// \brief Debugging and diagnostic assertions
/// \details <tt>CRYPTOPP_ASSERT</tt> is the library's debugging and diagnostic
/// assertion. <tt>CRYPTOPP_ASSERT</tt> is enabled by <tt>CRYPTOPP_DEBUG</tt>,
/// <tt>DEBUG</tt> or <tt>_DEBUG</tt>.
/// \details <tt>CRYPTOPP_ASSERT</tt> raises a <tt>SIGTRAP</tt> (Unix) or calls
/// <tt>DebugBreak()</tt> (Windows).
/// \details <tt>CRYPTOPP_ASSERT</tt> is only in effect when the user requests a
/// debug configuration. <tt>NDEBUG</tt> (or failure to define it) does not
/// affect <tt>CRYPTOPP_ASSERT</tt>.
/// \since Crypto++ 5.6.5
/// \sa DebugTrapHandler, <A
/// HREF="http://github.com/weidai11/cryptopp/issues/277">Issue 277</A>,
/// <A HREF="http://seclists.org/oss-sec/2016/q3/520">CVE-2016-7420</A>
#ifndef CRYPTOPP_TRAP_H
#define CRYPTOPP_TRAP_H
#include "config.h"
#if defined(CRYPTOPP_DEBUG)
# include <iostream>
# include <sstream>
# if defined(UNIX_SIGNALS_AVAILABLE)
# include "ossig.h"
# elif defined(CRYPTOPP_WIN32_AVAILABLE) && !defined(__CYGWIN__)
extern "C" __declspec(dllimport) void __stdcall DebugBreak();
extern "C" __declspec(dllimport) int __stdcall IsDebuggerPresent();
# endif
#endif // CRYPTOPP_DEBUG
// ************** run-time assertion ***************
#if defined(CRYPTOPP_DOXYGEN_PROCESSING)
/// \brief Debugging and diagnostic assertion
/// \details <tt>CRYPTOPP_ASSERT</tt> is the library's debugging and diagnostic
/// assertion. <tt>CRYPTOPP_ASSERT</tt> is enabled by the preprocessor macros
/// <tt>CRYPTOPP_DEBUG</tt>, <tt>DEBUG</tt> or <tt>_DEBUG</tt>.
/// \details <tt>CRYPTOPP_ASSERT</tt> raises a <tt>SIGTRAP</tt> (Unix) or calls
/// <tt>DebugBreak()</tt> (Windows). <tt>CRYPTOPP_ASSERT</tt> is only in effect
/// when the user explicitly requests a debug configuration.
/// \details If you want to ensure <tt>CRYPTOPP_ASSERT</tt> is inert, then <em>do
/// not</em> define <tt>CRYPTOPP_DEBUG</tt>, <tt>DEBUG</tt> or <tt>_DEBUG</tt>.
/// Avoiding the defines means <tt>CRYPTOPP_ASSERT</tt> is preprocessed into an
/// empty string.
/// \details The traditional Posix define <tt>NDEBUG</tt> has no effect on
/// <tt>CRYPTOPP_DEBUG</tt>, <tt>CRYPTOPP_ASSERT</tt> or DebugTrapHandler.
/// \details An example of using CRYPTOPP_ASSERT and DebugTrapHandler is shown
/// below. The library's test program, <tt>cryptest.exe</tt> (from test.cpp),
/// exercises the structure:
/// <pre>
/// \#if defined(CRYPTOPP_DEBUG) && defined(UNIX_SIGNALS_AVAILABLE)
/// static const DebugTrapHandler g_dummyHandler;
/// \#endif
///
/// int main(int argc, char* argv[])
/// {
/// CRYPTOPP_ASSERT(argv != nullptr);
/// ...
/// }
/// </pre>
/// \since Crypto++ 5.6.5
/// \sa DebugTrapHandler, SignalHandler, <A
/// HREF="http://github.com/weidai11/cryptopp/issues/277">Issue 277</A>,
/// <A HREF="http://seclists.org/oss-sec/2016/q3/520">CVE-2016-7420</A>
# define CRYPTOPP_ASSERT(exp) { ... }
#endif
#if defined(CRYPTOPP_DEBUG)
# if defined(UNIX_SIGNALS_AVAILABLE) || defined(__CYGWIN__)
# define CRYPTOPP_ASSERT(exp) { \
if (!(exp)) { \
std::ostringstream oss; \
oss << "Assertion failed: " << __FILE__ << "(" \
<< __LINE__ << "): " << __func__ \
<< std::endl; \
std::cout << std::flush; \
std::cerr << oss.str(); \
raise(SIGTRAP); \
} \
}
# elif CRYPTOPP_DEBUG && defined(CRYPTOPP_WIN32_AVAILABLE)
# define CRYPTOPP_ASSERT(exp) { \
if (!(exp)) { \
std::ostringstream oss; \
oss << "Assertion failed: " << __FILE__ << "(" \
<< __LINE__ << "): " << __FUNCTION__ \
<< std::endl; \
std::cout << std::flush; \
std::cerr << oss.str(); \
if (IsDebuggerPresent()) {DebugBreak();} \
} \
}
# endif // Unix or Windows
#endif // CRYPTOPP_DEBUG
// Remove CRYPTOPP_ASSERT in non-debug builds.
#ifndef CRYPTOPP_ASSERT
# define CRYPTOPP_ASSERT(exp) (void)0
#endif
NAMESPACE_BEGIN(CryptoPP)
// ************** SIGTRAP handler ***************
#if (CRYPTOPP_DEBUG && defined(UNIX_SIGNALS_AVAILABLE)) || defined(CRYPTOPP_DOXYGEN_PROCESSING)
/// \brief Default SIGTRAP handler
/// \details DebugTrapHandler() can be used by a program to install an empty
/// SIGTRAP handler. If present, the handler ensures there is a signal
/// handler in place for <tt>SIGTRAP</tt> raised by
/// <tt>CRYPTOPP_ASSERT</tt>. If <tt>CRYPTOPP_ASSERT</tt> raises
/// <tt>SIGTRAP</tt> <em>without</em> a handler, then one of two things can
/// occur. First, the OS might allow the program to continue. Second, the OS
/// might terminate the program. OS X allows the program to continue, while
/// some Linuxes terminate the program.
/// \details If DebugTrapHandler detects another handler in place, then it will
/// not install a handler. This ensures a debugger can gain control of the
/// <tt>SIGTRAP</tt> signal without contention. It also allows multiple
/// DebugTrapHandler to be created without contentious or unusual behavior.
/// Though multiple DebugTrapHandler can be created, a program should only
/// create one, if needed.
/// \details A DebugTrapHandler is subject to C++ static initialization
/// [dis]order. If you need to install a handler and it must be installed
/// early, then reference the code associated with
/// <tt>CRYPTOPP_INIT_PRIORITY</tt> in cryptlib.cpp and cpu.cpp.
/// \details If you want to ensure <tt>CRYPTOPP_ASSERT</tt> is inert, then
/// <em>do not</em> define <tt>CRYPTOPP_DEBUG</tt>, <tt>DEBUG</tt> or
/// <tt>_DEBUG</tt>. Avoiding the defines means <tt>CRYPTOPP_ASSERT</tt>
/// is processed into <tt>((void)0)</tt>.
/// \details The traditional Posix define <tt>NDEBUG</tt> has no effect on
/// <tt>CRYPTOPP_DEBUG</tt>, <tt>CRYPTOPP_ASSERT</tt> or DebugTrapHandler.
/// \details An example of using \ref CRYPTOPP_ASSERT "CRYPTOPP_ASSERT" and
/// DebugTrapHandler is shown below. The library's test program,
/// <tt>cryptest.exe</tt> (from test.cpp), exercises the structure:
/// <pre>
/// \#if defined(CRYPTOPP_DEBUG) && defined(UNIX_SIGNALS_AVAILABLE)
/// const DebugTrapHandler g_dummyHandler;
/// \#endif
///
/// int main(int argc, char* argv[])
/// {
/// CRYPTOPP_ASSERT(argv != nullptr);
/// ...
/// }
/// </pre>
/// \since Crypto++ 5.6.5
/// \sa \ref CRYPTOPP_ASSERT "CRYPTOPP_ASSERT", SignalHandler, <A
/// HREF="http://github.com/weidai11/cryptopp/issues/277">Issue 277</A>,
/// <A HREF="http://seclists.org/oss-sec/2016/q3/520">CVE-2016-7420</A>
#if defined(CRYPTOPP_DOXYGEN_PROCESSING)
class DebugTrapHandler : public SignalHandler<SIGTRAP, false> { };
#else
typedef SignalHandler<SIGTRAP, false> DebugTrapHandler;
#endif
#endif // Linux, Unix and Documentation
NAMESPACE_END
#endif // CRYPTOPP_TRAP_H
DebugTrapHandler
Default SIGTRAP handler.
Definition: trap.h:154
config.h
Library configuration file.
CryptoPP
Crypto++ library namespace.
ossig.h
Utility class for trapping OS signals.
SignalHandler
Signal handler for Linux and Unix compatibles.
Definition: ossig.h:59