(#4925) - com_pipefile to create a named pipe for sending commands from other processes, patch by Chris Schwarz

README

@@ -158,6 +158,10 @@ New cvars
   com_maxfpsMinimized               - Maximum frames per second when minimized
   com_busyWait                      - Will use a busy loop to wait for rendering
                                       next frame when set to non-zero value
+  com_pipefile                      - Specify filename to create a named pipe 
+                                      through which other processes can control
+                                      the server while it is running. 
+                                      Nonfunctional on Windows.
 
   in_joystickNo                     - select which joystick to use
   in_availableJoysticks             - list of available Joysticks

code/qcommon/common.c

@@ -50,6 +50,7 @@ jmp_buf abortframe;		// an ERR_DROP occured, exit the entire frame
 
 
 FILE *debuglogfile;
+static fileHandle_t pipefile;
 static fileHandle_t logfile;
 fileHandle_t	com_journalFile;			// events are written here
 fileHandle_t	com_journalDataFile;		// config files are written here
@@ -66,6 +67,7 @@ cvar_t	*com_timedemo;
 cvar_t	*com_sv_running;
 cvar_t	*com_cl_running;
 cvar_t	*com_logfile;		// 1 = buffer log, 2 = flush after each print
+cvar_t	*com_pipefile;
 cvar_t	*com_showtrace;
 cvar_t	*com_version;
 cvar_t	*com_blood;
@@ -2768,9 +2770,36 @@ void Com_Init( char *commandLine ) {
 	Com_Printf ("Altivec support is %s\n", com_altivec->integer ? "enabled" : "disabled");
 #endif
 
+	com_pipefile = Cvar_Get( "com_pipefile", "", CVAR_ARCHIVE|CVAR_LATCH );
+	if( com_pipefile->string[0] )
+	{
+		pipefile = FS_FCreateOpenPipeFile( com_pipefile->string );
+	}
+
 	Com_Printf ("--- Common Initialization Complete ---\n");
 }
 
+/*
+===============
+Com_ReadFromPipe
+
+Read whatever is in com_pipefile, if anything, and execute it
+===============
+*/
+void Com_ReadFromPipe( void )
+{
+	char buffer[MAX_STRING_CHARS] = {""};
+	qboolean read;
+
+	if( !pipefile )
+		return;
+
+	read = FS_Read( buffer, sizeof( buffer ), pipefile );
+	if( read )
+		Cbuf_ExecuteText( EXEC_APPEND, buffer );
+}
+
+
 //==================================================================
 
 void Com_WriteConfigToFile( const char *filename ) {
@@ -3097,6 +3126,8 @@ void Com_Frame( void ) {
 		c_pointcontents = 0;
 	}
 
+	Com_ReadFromPipe( );
+
 	com_frameNumber++;
 }
 
@@ -3116,6 +3147,11 @@ void Com_Shutdown (void) {
 		com_journalFile = 0;
 	}
 
+	if( pipefile ) {
+		FS_FCloseFile( pipefile );
+		FS_HomeRemove( com_pipefile->string );
+	}
+
 }
 
 //------------------------------------------------------------------------

code/qcommon/files.c

@@ -905,6 +905,50 @@ fileHandle_t FS_FOpenFileAppend( const char *filename ) {
 	return f;
 }
 
+/*
+===========
+FS_FCreateOpenPipeFile
+
+===========
+*/
+fileHandle_t FS_FCreateOpenPipeFile( const char *filename ) {
+	char	    		*ospath;
+	FILE					*fifo;
+	fileHandle_t	f;
+
+	if ( !fs_searchpaths ) {
+		Com_Error( ERR_FATAL, "Filesystem call made without initialization\n" );
+	}
+
+	f = FS_HandleForFile();
+	fsh[f].zipFile = qfalse;
+
+	Q_strncpyz( fsh[f].name, filename, sizeof( fsh[f].name ) );
+
+	// don't let sound stutter
+	S_ClearSoundBuffer();
+
+	ospath = FS_BuildOSPath( fs_homepath->string, fs_gamedir, filename );
+
+	if ( fs_debug->integer ) {
+		Com_Printf( "FS_FCreateOpenPipeFile: %s\n", ospath );
+	}
+
+	FS_CheckFilenameIsNotExecutable( ospath, __func__ );
+
+	fifo = Sys_Mkfifo( ospath );
+	if( fifo ) {
+		fsh[f].handleFiles.file.o = fifo;
+		fsh[f].handleSync = qfalse;
+	}
+	else
+	{
+		f = 0;
+	}
+
+	return f;
+}
+
 /*
 ===========
 FS_FilenameCompare

code/qcommon/qcommon.h

@@ -626,6 +626,7 @@ int		FS_GetModList(  char *listbuf, int bufsize );
 
 fileHandle_t	FS_FOpenFileWrite( const char *qpath );
 fileHandle_t	FS_FOpenFileAppend( const char *filename );
+fileHandle_t	FS_FCreateOpenPipeFile( const char *filename );
 // will properly create any needed paths and deal with seperater character issues
 
 fileHandle_t FS_SV_FOpenFileWrite( const char *filename );
@@ -1094,6 +1095,7 @@ qboolean	Sys_IsLANAddress (netadr_t adr);
 void		Sys_ShowIP(void);
 
 qboolean Sys_Mkdir( const char *path );
+FILE	*Sys_Mkfifo( const char *ospath );
 char	*Sys_Cwd( void );
 void	Sys_SetDefaultInstallPath(const char *path);
 char	*Sys_DefaultInstallPath(void);

code/sys/sys_unix.c

@@ -247,6 +247,31 @@ qboolean Sys_Mkdir( const char *path )
 	return qtrue;
 }
 
+/*
+==================
+Sys_Mkfifo
+==================
+*/
+FILE *Sys_Mkfifo( const char *ospath )
+{
+	FILE	*fifo; 
+	int		result;
+	int		fn;
+
+	result = mkfifo( ospath, 0600 );
+	if( result != 0 )
+		return NULL;
+
+	fifo = fopen( ospath, "w+" );
+	if( fifo )
+	{
+		fn = fileno( fifo );
+		fcntl( fn, F_SETFL, O_NONBLOCK );
+	}
+
+	return fifo;
+}
+
 /*
 ==================
 Sys_Cwd

code/sys/sys_win32.c

@@ -320,6 +320,17 @@ qboolean Sys_Mkdir( const char *path )
 	return qtrue;
 }
 
+/*
+==================
+Sys_Mkfifo
+Noop on windows because named pipes do not function the same way
+==================
+*/
+FILE *Sys_Mkfifo( const char *ospath )
+{
+	return NULL;
+}
+
 /*
 ==============
 Sys_Cwd