common.c

quakeIII源码这个不用我多说吧

			if ( com_sv_running->integer ) {
				Com_RunAndTimeServerPacket( &evFrom, &buf );
			} else {
				CL_PacketEvent( evFrom, &buf );
			}
			break;
		}

		// free any block data
		if ( ev.evPtr ) {
			Z_Free( ev.evPtr );
		}
	}

	return 0;	// never reached
}

/*
================
Com_Milliseconds

Can be used for profiling, but will be journaled accurately
================
*/
int Com_Milliseconds (void) {
	sysEvent_t	ev;

	// get events and push them until we get a null event with the current time
	do {

		ev = Com_GetRealEvent();
		if ( ev.evType != SE_NONE ) {
			Com_PushEvent( &ev );
		}
	} while ( ev.evType != SE_NONE );
	
	return ev.evTime;
}

//============================================================================

/*
=============
Com_Error_f

Just throw a fatal error to
test error shutdown procedures
=============
*/
static void Com_Error_f (void) {
	if ( Cmd_Argc() > 1 ) {
		Com_Error( ERR_DROP, "Testing drop error" );
	} else {
		Com_Error( ERR_FATAL, "Testing fatal error" );
	}
}


/*
=============
Com_Freeze_f

Just freeze in place for a given number of seconds to test
error recovery
=============
*/
static void Com_Freeze_f (void) {
	float	s;
	int		start, now;

	if ( Cmd_Argc() != 2 ) {
		Com_Printf( "freeze <seconds>\n" );
		return;
	}
	s = atof( Cmd_Argv(1) );

	start = Com_Milliseconds();

	while ( 1 ) {
		now = Com_Milliseconds();
		if ( ( now - start ) * 0.001 > s ) {
			break;
		}
	}
}

/*
=================
Com_Crash_f

A way to force a bus error for development reasons
=================
*/
static void Com_Crash_f( void ) {
	* ( int * ) 0 = 0x12345678;
}

// TTimo: centralizing the cl_cdkey stuff after I discovered a buffer overflow problem with the dedicated server version
//   not sure it's necessary to have different defaults for regular and dedicated, but I don't want to risk it
//   https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=470
#ifndef DEDICATED
char	cl_cdkey[34] = "                                ";
#else
char	cl_cdkey[34] = "123456789";
#endif

/*
=================
Com_ReadCDKey
=================
*/
qboolean CL_CDKeyValidate( const char *key, const char *checksum );
void Com_ReadCDKey( const char *filename ) {
	fileHandle_t	f;
	char			buffer[33];
	char			fbuffer[MAX_OSPATH];

	sprintf(fbuffer, "%s/q3key", filename);

	FS_SV_FOpenFileRead( fbuffer, &f );
	if ( !f ) {
		Q_strncpyz( cl_cdkey, "                ", 17 );
		return;
	}

	Com_Memset( buffer, 0, sizeof(buffer) );

	FS_Read( buffer, 16, f );
	FS_FCloseFile( f );

	if (CL_CDKeyValidate(buffer, NULL)) {
		Q_strncpyz( cl_cdkey, buffer, 17 );
	} else {
		Q_strncpyz( cl_cdkey, "                ", 17 );
	}
}

/*
=================
Com_AppendCDKey
=================
*/
void Com_AppendCDKey( const char *filename ) {
	fileHandle_t	f;
	char			buffer[33];
	char			fbuffer[MAX_OSPATH];

	sprintf(fbuffer, "%s/q3key", filename);

	FS_SV_FOpenFileRead( fbuffer, &f );
	if (!f) {
		Q_strncpyz( &cl_cdkey[16], "                ", 17 );
		return;
	}

	Com_Memset( buffer, 0, sizeof(buffer) );

	FS_Read( buffer, 16, f );
	FS_FCloseFile( f );

	if (CL_CDKeyValidate(buffer, NULL)) {
		strcat( &cl_cdkey[16], buffer );
	} else {
		Q_strncpyz( &cl_cdkey[16], "                ", 17 );
	}
}

#ifndef DEDICATED // bk001204
/*
=================
Com_WriteCDKey
=================
*/
static void Com_WriteCDKey( const char *filename, const char *ikey ) {
	fileHandle_t	f;
	char			fbuffer[MAX_OSPATH];
	char			key[17];


	sprintf(fbuffer, "%s/q3key", filename);


	Q_strncpyz( key, ikey, 17 );

	if(!CL_CDKeyValidate(key, NULL) ) {
		return;
	}

	f = FS_SV_FOpenFileWrite( fbuffer );
	if ( !f ) {
		Com_Printf ("Couldn't write %s.\n", filename );
		return;
	}

	FS_Write( key, 16, f );

	FS_Printf( f, "\n// generated by quake, do not modify\r\n" );
	FS_Printf( f, "// Do not give this file to ANYONE.\r\n" );
	FS_Printf( f, "// id Software and Activision will NOT ask you to send this file to them.\r\n");

	FS_FCloseFile( f );
}
#endif


/*
=================
Com_Init
=================
*/
void Com_Init( char *commandLine ) 
{
	char	*s;

	Com_Printf( "%s %s %s\n", Q3_VERSION, CPUSTRING, __DATE__ );

	if ( setjmp (abortframe) ) {
		Sys_Error ("Error during initialization");
	}

  // bk001129 - do this before anything else decides to push events
  Com_InitPushEvent();

	Com_InitSmallZoneMemory();
	Cvar_Init ();

	// prepare enough of the subsystems to handle
	// cvar and command buffer management
	Com_ParseCommandLine( commandLine );

//	Swap_Init ();
	Cbuf_Init ();

	Com_InitZoneMemory();
	Cmd_Init ();

	// override anything from the config files with command line args
	Com_StartupVariable( NULL );

	// get the developer cvar set as early as possible
	Com_StartupVariable( "developer" );

	// done early so bind command exists
	CL_InitKeyCommands();

	FS_InitFilesystem ();

	Com_InitJournaling();

	Cbuf_AddText ("exec default.cfg\n");

	// skip the q3config.cfg if "safe" is on the command line
	if ( !Com_SafeMode() ) {
		Cbuf_AddText ("exec q3config.cfg\n");
	}

	Cbuf_AddText ("exec autoexec.cfg\n");

	Cbuf_Execute ();

	// override anything from the config files with command line args
	Com_StartupVariable( NULL );

  // get dedicated here for proper hunk megs initialization
#ifdef DEDICATED
	com_dedicated = Cvar_Get ("dedicated", "1", CVAR_ROM);
#else
	com_dedicated = Cvar_Get ("dedicated", "0", CVAR_LATCH);
#endif
	// allocate the stack based hunk allocator
	Com_InitHunkMemory();

	// if any archived cvars are modified after this, we will trigger a writing
	// of the config file
	cvar_modifiedFlags &= ~CVAR_ARCHIVE;

	//
	// init commands and vars
	//
	com_maxfps = Cvar_Get ("com_maxfps", "85", CVAR_ARCHIVE);
	com_blood = Cvar_Get ("com_blood", "1", CVAR_ARCHIVE);

	com_developer = Cvar_Get ("developer", "0", CVAR_TEMP );
	com_logfile = Cvar_Get ("logfile", "0", CVAR_TEMP );

	com_timescale = Cvar_Get ("timescale", "1", CVAR_CHEAT | CVAR_SYSTEMINFO );
	com_fixedtime = Cvar_Get ("fixedtime", "0", CVAR_CHEAT);
	com_showtrace = Cvar_Get ("com_showtrace", "0", CVAR_CHEAT);
	com_dropsim = Cvar_Get ("com_dropsim", "0", CVAR_CHEAT);
	com_viewlog = Cvar_Get( "viewlog", "0", CVAR_CHEAT );
	com_speeds = Cvar_Get ("com_speeds", "0", 0);
	com_timedemo = Cvar_Get ("timedemo", "0", CVAR_CHEAT);
	com_cameraMode = Cvar_Get ("com_cameraMode", "0", CVAR_CHEAT);

	cl_paused = Cvar_Get ("cl_paused", "0", CVAR_ROM);
	sv_paused = Cvar_Get ("sv_paused", "0", CVAR_ROM);
	com_sv_running = Cvar_Get ("sv_running", "0", CVAR_ROM);
	com_cl_running = Cvar_Get ("cl_running", "0", CVAR_ROM);
	com_buildScript = Cvar_Get( "com_buildScript", "0", 0 );

	com_introPlayed = Cvar_Get( "com_introplayed", "0", CVAR_ARCHIVE);

#if defined(_WIN32) && defined(_DEBUG)
	com_noErrorInterrupt = Cvar_Get( "com_noErrorInterrupt", "0", 0 );
#endif

	if ( com_dedicated->integer ) {
		if ( !com_viewlog->integer ) {
			Cvar_Set( "viewlog", "1" );
		}
	}

	if ( com_developer && com_developer->integer ) {
		Cmd_AddCommand ("error", Com_Error_f);
		Cmd_AddCommand ("crash", Com_Crash_f );
		Cmd_AddCommand ("freeze", Com_Freeze_f);
	}
	Cmd_AddCommand ("quit", Com_Quit_f);
	Cmd_AddCommand ("changeVectors", MSG_ReportChangeVectors_f );
	Cmd_AddCommand ("writeconfig", Com_WriteConfig_f );

	s = va("%s %s %s", Q3_VERSION, CPUSTRING, __DATE__ );
	com_version = Cvar_Get ("version", s, CVAR_ROM | CVAR_SERVERINFO );

	Sys_Init();
	Netchan_Init( Com_Milliseconds() & 0xffff );	// pick a port value that should be nice and random
	VM_Init();
	SV_Init();

	com_dedicated->modified = qfalse;
	if ( !com_dedicated->integer ) {
		CL_Init();
		Sys_ShowConsole( com_viewlog->integer, qfalse );
	}

	// set com_frameTime so that if a map is started on the
	// command line it will still be able to count on com_frameTime
	// being random enough for a serverid
	com_frameTime = Com_Milliseconds();

	// add + commands from command line
	if ( !Com_AddStartupCommands() ) {
		// if the user didn't give any commands, run default action
		if ( !com_dedicated->integer ) {
			Cbuf_AddText ("cinematic idlogo.RoQ\n");
			if( !com_introPlayed->integer ) {
				Cvar_Set( com_introPlayed->name, "1" );
				Cvar_Set( "nextmap", "cinematic intro.RoQ" );
			}
		}
	}

	// start in full screen ui mode
	Cvar_Set("r_uiFullScreen", "1");

	CL_StartHunkUsers();

	// make sure single player is off by default
	Cvar_Set("ui_singlePlayerActive", "0");

	com_fullyInitialized = qtrue;
	Com_Printf ("--- Common Initialization Complete ---\n");	
}

//==================================================================

void Com_WriteConfigToFile( const char *filename ) {
	fileHandle_t	f;

	f = FS_FOpenFileWrite( filename );
	if ( !f ) {
		Com_Printf ("Couldn't write %s.\n", filename );
		return;
	}

	FS_Printf (f, "// generated by quake, do not modify\n");
	Key_WriteBindings (f);
	Cvar_WriteVariables (f);
	FS_FCloseFile( f );
}


/*
===============
Com_WriteConfiguration

Writes key bindings and archived cvars to config file if modified
===============
*/
void Com_WriteConfiguration( void ) {
#ifndef DEDICATED // bk001204
	cvar_t	*fs;
#endif
	// if we are quiting without fully initializing, make sure
	// we don't write out anything
	if ( !com_fullyInitialized ) {
		return;
	}

	if ( !(cvar_modifiedFlags & CVAR_ARCHIVE ) ) {
		return;
	}
	cvar_modifiedFlags &= ~CVAR_ARCHIVE;

	Com_WriteConfigToFile( "q3config.cfg" );

	// bk001119 - tentative "not needed for dedicated"
#ifndef DEDICATED
	fs = Cvar_Get ("fs_game", "", CVAR_INIT|CVAR_SYSTEMINFO );
	if (UI_usesUniqueCDKey() && fs && fs->string[0] != 0) {
		Com_WriteCDKey( fs->string, &cl_cdkey[16] );
	} else {
		Com_WriteCDKey( "baseq3", cl_cdkey );
	}
#endif
}


/*
===============
Com_WriteConfig_f

Write the config file to a specific name
===============
*/
void Com_WriteConfig_f( void ) {
	char	filename[MAX_QPATH];

	if ( Cmd_Argc() != 2 ) {
		Com_Printf( "Usage: writeconfig <filename>\n" );
		return;
	}

	Q_strncpyz( filename, Cmd_Argv(1), sizeof( filename ) );
	COM_DefaultExtension( filename, sizeof( filename ), ".cfg" );
	Com_Printf( "Writing %s.\n", filename );
	Com_WriteConfigToFile( filename );
}

/*
================
Com_ModifyMsec
================
*/
int Com_ModifyMsec( int msec ) {
	int		clampTime;

	//
	// modify time for debugging values
	//
	if ( com_fixedtime->integer ) {
		msec = com_fixedtime->integer;
	} else if ( com_timescale->value ) {
		msec *= com_timescale->value;
	} else if (com_cameraMode->integer) {
		msec *= com_timescale->value;
	}
	
	// don't let it scale below 1 msec
	if ( msec < 1 && com_timescale->value) {
		msec = 1;
	}

	if ( com_dedicated->integer ) {
		// dedicated servers don't want to clamp for a much longer
		// period, because it would mess up all the client's views
		// of time.
		if ( msec > 500 ) {
			Com_Printf( "Hitch warning: %i msec frame time\n", msec );
		}
		clampTime = 5000;
	} else 
	if ( !com_sv_running->integer ) {
		// clients of remote servers do not want to clamp time, because
		// it would skew their view of the server's time temporarily
		clampTime = 5000;
	} else {
		// for local single player gaming
		// we may want to clamp the time to prevent players from
		// flying off edges when something hitches.
		clampTime = 200;
	}

	if ( msec > clampTime ) {
		msec = clampTime;
	}

	return msec;
}

/*
=================
Com_Frame
=================
*/
void Com_Frame( void ) {

	int		msec, minMsec;
	static int	lastTime;
	int key;
 
	int		timeBeforeFirstEvents;
	int           timeBeforeServer;
	int           timeBeforeEvents;
	int           timeBeforeClient;
	int           timeAfter;
  




	if ( setjmp (abortframe) ) {
		return;			// an ERR_DROP was thrown
	}

	// bk001204 - init to zero.
	//  also:  might be clobbered by `longjmp' or `vfork'
	timeBeforeFirstEvents =0;
	timeBeforeServer =0;
	timeBeforeEvents =0;
	timeBeforeClient = 0;
	timeAfter = 0;


	// old net chan encryption key
	key = 0x87243987;

	// write config file if anything changed
	Com_WriteConfiguration(); 

	// if "viewlog" has be