path: root/src/mongo/util/assert_util.h

// assert_util.h

/*    Copyright 2009 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program 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.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects
 *    for all of the code used other than as permitted herein. If you modify
 *    file(s) with this exception, you may extend this exception to your
 *    version of the file(s), but you are not obligated to do so. If you do not
 *    wish to do so, delete this exception statement from your version. If you
 *    delete this exception statement from all source files in the program,
 *    then also delete it in the license file.
 */

#pragma once

#include <typeinfo>
#include <string>

#include "mongo/base/status.h" // NOTE: This is safe as utils depend on base
#include "mongo/platform/compiler.h"
#include "mongo/logger/log_severity.h"
#include "mongo/logger/logger.h"
#include "mongo/logger/logstream_builder.h"
#include "mongo/util/concurrency/thread_name.h"
#include "mongo/util/debug_util.h"

#define MONGO_INCLUDE_INVARIANT_H_WHITELISTED
#include "mongo/util/invariant.h"
#undef MONGO_INCLUDE_INVARIANT_H_WHITELISTED

namespace mongo {

    enum CommonErrorCodes {
        OkCode = 0,
        SendStaleConfigCode = 13388 ,     // uassert( 13388 )
        RecvStaleConfigCode = 9996,       // uassert( 9996 )
        PrepareConfigsFailedCode = 13104, // uassert( 13104 )
        NotMasterOrSecondaryCode = 13436, // uassert( 13436 )
        NotMasterNoSlaveOkCode = 13435,   // uassert( 13435 )
        NotMaster = 10107,                // uassert( 10107 )
    };

    class AssertionCount {
    public:
        AssertionCount();
        void rollover();
        void condrollover( int newValue );

        int regular;
        int warning;
        int msg;
        int user;
        int rollovers;
    };

    extern AssertionCount assertionCount;

    class BSONObjBuilder;

    struct ExceptionInfo {
        ExceptionInfo() : msg(""),code(-1) {}
        ExceptionInfo( const char * m , int c )
            : msg( m ) , code( c ) {
        }
        ExceptionInfo( const std::string& m , int c )
            : msg( m ) , code( c ) {
        }
        void append( BSONObjBuilder& b , const char * m = "$err" , const char * c = "code" ) const ;
        std::string toString() const;
        bool empty() const { return msg.empty(); }
        void reset(){ msg = ""; code=-1; }
        std::string msg;
        int code;
    };

    /** helper class that builds error strings.  lighter weight than a StringBuilder, albeit less flexible.
        NOINLINE_DECL used in the constructor implementations as we are assuming this is a cold code path when used.

        example:
          throw UserException(123, ErrorMsg("blah", num_val));
    */
    class ErrorMsg {
    public:
        ErrorMsg(const char *msg, char ch);
        ErrorMsg(const char *msg, unsigned val);
        operator std::string() const { return buf; }
    private:
        char buf[256];
    };

    class DBException;
    std::string causedBy( const DBException& e );
    std::string causedBy( const std::string& e );

    /** Most mongo exceptions inherit from this; this is commonly caught in most threads */
    class DBException : public std::exception {
    public:
        DBException( const ExceptionInfo& ei ) : _ei(ei) { traceIfNeeded(*this); }
        DBException( const char * msg , int code ) : _ei(msg,code) { traceIfNeeded(*this); }
        DBException( const std::string& msg , int code ) : _ei(msg,code) { traceIfNeeded(*this); }
        virtual ~DBException() throw() { }

        virtual const char* what() const throw() { return _ei.msg.c_str(); }
        virtual int getCode() const { return _ei.code; }
        virtual void appendPrefix( std::stringstream& ss ) const { }
        virtual void addContext( const std::string& str ) {
            _ei.msg = str + causedBy( _ei.msg );
        }

        // Utilities for the migration to Status objects
        static ErrorCodes::Error convertExceptionCode(int exCode);

        Status toStatus(const std::string& context) const {
            return Status(convertExceptionCode(getCode()), context + causedBy(*this));
        }
        Status toStatus() const {
            return Status(convertExceptionCode(getCode()), this->what());
        }

        // context when applicable. otherwise ""
        std::string _shard;

        virtual std::string toString() const;

        const ExceptionInfo& getInfo() const { return _ei; }
    private:
        static void traceIfNeeded( const DBException& e );
    public:
        static bool traceExceptions;

    protected:
        ExceptionInfo _ei;
    };

    class AssertionException : public DBException {
    public:

        AssertionException( const ExceptionInfo& ei ) : DBException(ei) {}
        AssertionException( const char * msg , int code ) : DBException(msg,code) {}
        AssertionException( const std::string& msg , int code ) : DBException(msg,code) {}

        virtual ~AssertionException() throw() { }

        virtual bool severe() const { return true; }
        virtual bool isUserAssertion() const { return false; }
    };

    /* UserExceptions are valid errors that a user can cause, like out of disk space or duplicate key */
    class UserException : public AssertionException {
    public:
        UserException(int c , const std::string& m) : AssertionException( m , c ) {}
        virtual bool severe() const { return false; }
        virtual bool isUserAssertion() const { return true; }
        virtual void appendPrefix( std::stringstream& ss ) const;
    };

    class MsgAssertionException : public AssertionException {
    public:
        MsgAssertionException( const ExceptionInfo& ei ) : AssertionException( ei ) {}
        MsgAssertionException(int c, const std::string& m) : AssertionException( m , c ) {}
        virtual bool severe() const { return false; }
        virtual void appendPrefix( std::stringstream& ss ) const;
    };

    MONGO_COMPILER_NORETURN void verifyFailed(const char* expr, const char* file, unsigned line);
    MONGO_COMPILER_NORETURN void invariantOKFailed(const char* expr, const Status& status, const char *file, unsigned line);
    void wasserted(const char* expr, const char* file, unsigned line);
    MONGO_COMPILER_NORETURN void fassertFailed( int msgid );
    MONGO_COMPILER_NORETURN void fassertFailedNoTrace( int msgid );
    MONGO_COMPILER_NORETURN void fassertFailedWithStatus(
            int msgid, const Status& status);
    MONGO_COMPILER_NORETURN void fassertFailedWithStatusNoTrace(
            int msgid, const Status& status);

    /** a "user assertion".  throws UserAssertion.  logs.  typically used for errors that a user
        could cause, such as duplicate key, disk full, etc.
    */
    MONGO_COMPILER_NORETURN void uasserted(int msgid, const char *msg);
    MONGO_COMPILER_NORETURN void uasserted(int msgid , const std::string &msg);

    /** msgassert and massert are for errors that are internal but have a well defined error text
        std::string.  a stack trace is logged.
    */
    MONGO_COMPILER_NORETURN void msgassertedNoTrace(int msgid, const char *msg);
    MONGO_COMPILER_NORETURN void msgassertedNoTrace(int msgid, const std::string &msg);
    MONGO_COMPILER_NORETURN void msgasserted(int msgid, const char *msg);
    MONGO_COMPILER_NORETURN void msgasserted(int msgid, const std::string &msg);

    /* convert various types of exceptions to strings */
    std::string causedBy( const char* e );
    std::string causedBy( const DBException& e );
    std::string causedBy( const std::exception& e );
    std::string causedBy( const std::string& e );
    std::string causedBy( const std::string* e );
    std::string causedBy( const Status& e );

    /** aborts on condition failure */
    inline void fassert(int msgid, bool testOK) {
        if (MONGO_unlikely(!testOK)) fassertFailed(msgid);
    }

    inline void fassert(int msgid, const Status& status) {
        if (MONGO_unlikely(!status.isOK())) {
            fassertFailedWithStatus(msgid, status);
        }
    }

    inline void fassertNoTrace(int msgid, const Status& status) {
        if (MONGO_unlikely(!status.isOK())) {
            fassertFailedWithStatusNoTrace(msgid, status);
        }
    }


    /* "user assert".  if asserts, user did something wrong, not our code */
#define MONGO_uassert(msgid, msg, expr) do {                            \
        if (MONGO_unlikely(!(expr))) {                                      \
            ::mongo::uasserted(msgid, msg);                             \
        }                                                               \
    } while (false)

    inline void uassertStatusOK(const Status& status) {
        if (MONGO_unlikely(!status.isOK())) {
            uasserted((status.location() != 0 ? status.location() : status.code()),
                      status.reason());
        }
    }

    template<typename T>
    inline T uassertStatusOK(StatusWith<T> sw) {
        if (MONGO_unlikely(!sw.isOK())) {
            const auto& status = sw.getStatus();
            uasserted((status.location() != 0 ? status.location() : status.code()),
                      status.reason());
        }
        return std::move(sw.getValue());
    }

    template<typename T>
    inline T fassertStatusOK(int msgid, StatusWith<T> sw) {
        if (MONGO_unlikely(!sw.isOK())) {
            fassertFailedWithStatus(msgid, sw.getStatus());
        }
        return std::move(sw.getValue());
    }

    /* warning only - keeps going */
#define MONGO_wassert(_Expression) do {                                 \
        if (MONGO_unlikely(!(_Expression))) {                               \
            ::mongo::wasserted(#_Expression, __FILE__, __LINE__);       \
        }                                                               \
    } while (false)

    /* display a message, no context, and throw assertionexception

       easy way to throw an exception and log something without our stack trace
       display happening.
    */
#define MONGO_massert(msgid, msg, expr) do {    \
        if (MONGO_unlikely(!(expr))) {              \
            ::mongo::msgasserted(msgid, msg);   \
        }                                       \
    } while (false)

    inline void massertStatusOK(const Status& status) {
        if (MONGO_unlikely(!status.isOK())) {
            msgasserted((status.location() != 0 ? status.location() : status.code()),
                        status.reason());
        }
    }

    inline void massertNoTraceStatusOK(const Status& status) {
        if (MONGO_unlikely(!status.isOK())) {
            msgassertedNoTrace((status.location() != 0 ? status.location() : status.code()),
                        status.reason());
        }
    }

    /* same as massert except no msgid */
#define MONGO_verify(_Expression) do {                                  \
        if (MONGO_unlikely(!(_Expression))) {                           \
            ::mongo::verifyFailed(#_Expression, __FILE__, __LINE__);    \
        }                                                               \
    } while (false)


#define MONGO_invariantOK(expression) do {                                                    \
    const ::mongo::Status _invariantOK_status = expression;                                   \
        if (MONGO_unlikely(!_invariantOK_status.isOK())) {                                    \
            ::mongo::invariantOKFailed(#expression, _invariantOK_status, __FILE__, __LINE__); \
        }                                                                                     \
    } while (false)

#define verify(expression) MONGO_verify(expression)
#define invariantOK MONGO_invariantOK
#define uassert MONGO_uassert
#define wassert MONGO_wassert
#define massert MONGO_massert

    // some special ids that we want to duplicate

    // > 10000 asserts
    // < 10000 UserException

    enum { ASSERT_ID_DUPKEY = 11000 };

    std::string demangleName( const std::type_info& typeinfo );

    /**
     * A utility function that converts an exception to a Status.
     * Only call this function when there is an active exception
     * (e.g. in a catch block).
     *
     * Note: this technique was created by Lisa Lippincott.
     *
     * Example usage:
     *
     *   Status myFunc() {
     *       try {
     *           funcThatThrows();
     *           return Status::OK();
     *       } catch (...) {
     *           return exceptionToStatus();
     *       }
     *   }
     */
    Status exceptionToStatus();

} // namespace mongo

#define MONGO_ASSERT_ON_EXCEPTION( expression ) \
    try { \
        expression; \
    } catch ( const std::exception &e ) { \
        std::stringstream ss; \
        ss << "caught exception: " << e.what() << ' ' << __FILE__ << ' ' << __LINE__; \
        msgasserted( 13294 , ss.str() ); \
    } catch ( ... ) { \
        massert( 10437 ,  "unknown exception" , false ); \
    }

#define MONGO_ASSERT_ON_EXCEPTION_WITH_MSG( expression, msg ) \
    try { \
        expression; \
    } catch ( const std::exception &e ) { \
        std::stringstream ss; \
        ss << msg << " caught exception exception: " << e.what();   \
        msgasserted( 14043 , ss.str() );        \
    } catch ( ... ) { \
        msgasserted( 14044 , std::string("unknown exception") + msg );   \
    }

#define DESTRUCTOR_GUARD MONGO_DESTRUCTOR_GUARD
#define MONGO_DESTRUCTOR_GUARD( expression ) \
    try { \
        expression; \
    } catch ( const std::exception &e ) { \
        ::mongo::logger::LogstreamBuilder(::mongo::logger::globalLogDomain(), \
                                          ::mongo::getThreadName(), \
                                          ::mongo::logger::LogSeverity::Log()) \
            << "caught exception (" << e.what() << ") in destructor (" << __FUNCTION__ \
            << ")" << std::endl; \
    } catch ( ... ) { \
        ::mongo::logger::LogstreamBuilder(::mongo::logger::globalLogDomain(), \
                                          ::mongo::getThreadName(), \
                                          ::mongo::logger::LogSeverity::Log()) \
            << "caught unknown exception in destructor (" << __FUNCTION__ << ")" \
            << std::endl; \
    }

/**
 * The purpose of this macro is to instruct the compiler that a line of code will never be reached.
 *
 * Example:
 *     // code above checks that expr can only be FOO or BAR
 *     switch (expr) {
 *     case FOO: { ... }
 *     case BAR: { ... }
 *     default:
 *         MONGO_UNREACHABLE;
 */

#define MONGO_UNREACHABLE ::mongo::invariantFailed("Hit a MONGO_UNREACHABLE!", __FILE__, __LINE__);