The Quake sources as originally release under the GPL license on December 21, 1999

QW/client/cvar.h

@@ -0,0 +1,97 @@
+/*
+Copyright (C) 1996-1997 Id Software, Inc.
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+*/
+// cvar.h
+
+/*
+
+cvar_t variables are used to hold scalar or string variables that can be changed or displayed at the console or prog code as well as accessed directly
+in C code.
+
+it is sufficient to initialize a cvar_t with just the first two fields, or
+you can add a ,true flag for variables that you want saved to the configuration
+file when the game is quit:
+
+cvar_t	r_draworder = {"r_draworder","1"};
+cvar_t	scr_screensize = {"screensize","1",true};
+
+Cvars must be registered before use, or they will have a 0 value instead of the float interpretation of the string.  Generally, all cvar_t declarations should be registered in the apropriate init function before any console commands are executed:
+Cvar_RegisterVariable (&host_framerate);
+
+
+C code usually just references a cvar in place:
+if ( r_draworder.value )
+
+It could optionally ask for the value to be looked up for a string name:
+if (Cvar_VariableValue ("r_draworder"))
+
+Interpreted prog code can access cvars with the cvar(name) or
+cvar_set (name, value) internal functions:
+teamplay = cvar("teamplay");
+cvar_set ("registered", "1");
+
+The user can access cvars from the console in two ways:
+r_draworder			prints the current value
+r_draworder 0		sets the current value to 0
+Cvars are restricted from having the same names as commands to keep this
+interface from being ambiguous.
+*/
+
+typedef struct cvar_s
+{
+	char	*name;
+	char	*string;
+	qboolean archive;		// set to true to cause it to be saved to vars.rc
+	qboolean info;			// added to serverinfo or userinfo when changed
+	float	value;
+	struct cvar_s *next;
+} cvar_t;
+
+void 	Cvar_RegisterVariable (cvar_t *variable);
+// registers a cvar that allready has the name, string, and optionally the
+// archive elements set.
+
+void 	Cvar_Set (char *var_name, char *value);
+// equivelant to "<name> <variable>" typed at the console
+
+void	Cvar_SetValue (char *var_name, float value);
+// expands value to a string and calls Cvar_Set
+
+float	Cvar_VariableValue (char *var_name);
+// returns 0 if not defined or non numeric
+
+char	*Cvar_VariableString (char *var_name);
+// returns an empty string if not defined
+
+char 	*Cvar_CompleteVariable (char *partial);
+// attempts to match a partial variable name for command line completion
+// returns NULL if nothing fits
+
+qboolean Cvar_Command (void);
+// called by Cmd_ExecuteString when Cmd_Argv(0) doesn't match a known
+// command.  Returns true if the command was a variable reference that
+// was handled. (print or change)
+
+void 	Cvar_WriteVariables (FILE *f);
+// Writes lines containing "set variable value" for all variables
+// with the archive flag set to true.
+
+cvar_t *Cvar_FindVar (char *var_name);
+
+extern cvar_t	*cvar_vars;