cvar.c

Go to the documentation of this file.

/*
Copyright (C) 1996-1997 Id Software, Inc.
Copyright (C) 2000-2021 DarkPlaces contributors
 
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.c -- dynamic variable tracking
 
#include "quakedef.h"
 
const char *cvar_dummy_description = "custom cvar";
static const char *cvar_null_string = "";
 
cvar_state_t cvars_all;
cvar_state_t cvars_null;
 
/*
============
Cvar_FindVar
============
*/
cvar_t *Cvar_FindVar(cvar_state_t *cvars, const char *var_name, unsigned neededflags)
{
    unsigned hashindex;
    cvar_hash_t *hash;
 
    // use hash lookup to minimize search time
    hashindex = CRC_Block((const unsigned char *)var_name, strlen(var_name)) % CVAR_HASHSIZE;
    for (hash = cvars->hashtable[hashindex];hash;hash = hash->next)
        if (!strcmp (var_name, hash->cvar->name) && (hash->cvar->flags & neededflags))
            return hash->cvar;
        else
            for (char **alias = hash->cvar->aliases; alias && *alias; alias++)
                if (!strcmp (var_name, *alias) && (hash->cvar->flags & neededflags))
                    return hash->cvar;
    return NULL;
}
 
cvar_t *Cvar_FindVarAfter(cvar_state_t *cvars, const char *prev_var_name, unsigned neededflags)
{
    cvar_t *var;
 
    if (*prev_var_name)
    {
        var = Cvar_FindVar(cvars, prev_var_name, neededflags);
        if (!var)
            return NULL;
        var = var->next;
    }
    else
        var = cvars->vars;
 
    // search for the next cvar matching the needed flags
    while (var)
    {
        if (var->flags & neededflags)
            break;
        var = var->next;
    }
    return var;
}
 
static cvar_hash_t **Cvar_FindVarLink(cvar_state_t *cvars, const char *var_name, cvar_t **prev_alpha, unsigned neededflags)
{
    unsigned hashindex;
    cvar_t *cvar;
    cvar_hash_t **hashlinkptr;
 
    // use hash lookup to minimize search time
    hashindex = CRC_Block((const unsigned char *)var_name, strlen(var_name)) % CVAR_HASHSIZE;
    if(prev_alpha) *prev_alpha = NULL;
    hashlinkptr = &cvars->hashtable[hashindex];
    for (hashlinkptr = &cvars->hashtable[hashindex]; *hashlinkptr; hashlinkptr = &(*hashlinkptr)->next)
    {
        cvar = (*hashlinkptr)->cvar;
        if (!strcmp (var_name, cvar->name) && (cvar->flags & neededflags))
            goto match;
        else
            for (char **alias = cvar->aliases; alias && *alias; alias++)
                if (!strcmp (var_name, *alias) && (cvar->flags & neededflags))
                    goto match;
    }
    return NULL;
 
match:
    if(!prev_alpha || cvar == cvars->vars)
        return hashlinkptr;
    *prev_alpha = cvars->vars;
    // if prev_alpha happens to become NULL then there has been some inconsistency elsewhere
    // already - should I still insert '*prev_alpha &&' in the loop?
    while((*prev_alpha)->next != cvar)
        *prev_alpha = (*prev_alpha)->next;
    return hashlinkptr;
}
 
/*
============
Cvar_VariableValue
============
*/
float Cvar_VariableValueOr(cvar_state_t *cvars, const char *var_name, float def, unsigned neededflags)
{
    cvar_t *var;
 
    var = Cvar_FindVar(cvars, var_name, neededflags);
    if (!var)
        return def;
    return atof (var->string);
}
 
float Cvar_VariableValue(cvar_state_t *cvars, const char *var_name, unsigned neededflags)
{
    return Cvar_VariableValueOr(cvars, var_name, 0, neededflags);
}
 
/*
============
Cvar_VariableString
============
*/
const char *Cvar_VariableStringOr(cvar_state_t *cvars, const char *var_name, const char *def, unsigned neededflags)
{
    cvar_t *var;
 
    var = Cvar_FindVar(cvars, var_name, neededflags);
    if (!var)
        return def;
    return var->string;
}
 
const char *Cvar_VariableString(cvar_state_t *cvars, const char *var_name, unsigned neededflags)
{
    return Cvar_VariableStringOr(cvars, var_name, cvar_null_string, neededflags);
}
 
/*
============
Cvar_VariableDefString
============
*/
const char *Cvar_VariableDefString(cvar_state_t *cvars, const char *var_name, unsigned neededflags)
{
    cvar_t *var;
 
    var = Cvar_FindVar(cvars, var_name, neededflags);
    if (!var)
        return cvar_null_string;
    return var->defstring;
}
 
/*
============
Cvar_VariableDescription
============
*/
const char *Cvar_VariableDescription(cvar_state_t *cvars, const char *var_name, unsigned neededflags)
{
    cvar_t *var;
 
    var = Cvar_FindVar(cvars, var_name, neededflags);
    if (!var)
        return cvar_null_string;
    return var->description;
}
 
 
/*
============
Cvar_CompleteVariable
============
*/
const char *Cvar_CompleteVariable(cvar_state_t *cvars, const char *partial, unsigned neededflags)
{
    cvar_t      *cvar;
    size_t      len;
 
    len = strlen(partial);
 
    if (!len)
        return NULL;
 
// check functions
    for (cvar=cvars->vars ; cvar ; cvar=cvar->next)
        if (!strncasecmp (partial,cvar->name, len) && (cvar->flags & neededflags))
            return cvar->name;
 
    return NULL;
}
 
 
/*
    CVar_CompleteCountPossible
 
    New function for tab-completion system
    Added by EvilTypeGuy
    Thanks to Fett erich@heintz.com
 
*/
int Cvar_CompleteCountPossible(cvar_state_t *cvars, const char *partial, unsigned neededflags)
{
    cvar_t  *cvar;
    size_t  len;
    int     h;
 
    h = 0;
    len = strlen(partial);
 
    if (!len)
        return  0;
 
    // Loop through the cvars and count all possible matches
    for (cvar = cvars->vars; cvar; cvar = cvar->next)
        if (!strncasecmp(partial, cvar->name, len) && (cvar->flags & neededflags))
            h++;
        else
            for (char **alias = cvar->aliases; alias && *alias; alias++)
                if (!strncasecmp(partial, *alias, len) && (cvar->flags & neededflags))
                    h++;
        
    return h;
}
 
/*
    CVar_CompleteBuildList
 
    New function for tab-completion system
    Added by EvilTypeGuy
    Thanks to Fett erich@heintz.com
    Thanks to taniwha
 
*/
const char **Cvar_CompleteBuildList(cvar_state_t *cvars, const char *partial, unsigned neededflags)
{
    const cvar_t *cvar;
    size_t len = 0;
    size_t bpos = 0;
    size_t sizeofbuf = (Cvar_CompleteCountPossible(cvars, partial, neededflags) + 1) * sizeof(const char *);
    const char **buf;
 
    len = strlen(partial);
    buf = (const char **)Mem_Alloc(tempmempool, sizeofbuf + sizeof(const char *));
    // Loop through the alias list and print all matches
    for (cvar = cvars->vars; cvar; cvar = cvar->next)
        if (!strncasecmp(partial, cvar->name, len) && (cvar->flags & neededflags))
            buf[bpos++] = cvar->name;
        else
            for (char **alias = cvar->aliases; alias && *alias; alias++)
                if (!strncasecmp(partial, *alias, len) && (cvar->flags & neededflags))
                    buf[bpos++] = *alias;
        
 
    buf[bpos] = NULL;
    return buf;
}
 
void Cvar_PrintHelp(cvar_t *cvar, const char *name, qbool full)
{
    // Aliases are purple, cvars are yellow
    if (strcmp(cvar->name, name))
        Con_Printf("^6%s^7 (alias of ^3%s^7)", name, cvar->name);
    else
        Con_Printf("^3%s^7", name);
    Con_Printf(" is \"%s^7\" [\"%s^7\"]", ((cvar->flags & CF_PRIVATE) ? "********"/*hunter2*/ : cvar->string), cvar->defstring);
    if (full)
        Con_Printf(" %s", cvar->description);
    Con_Print("\n");
}
 
// written by LadyHavoc
void Cvar_CompleteCvarPrint(cvar_state_t *cvars, const char *partial, unsigned neededflags)
{
    cvar_t *cvar;
    size_t len = strlen(partial);
    // Loop through the command list and print all matches
    for (cvar = cvars->vars; cvar; cvar = cvar->next)
        if (!strncasecmp(partial, cvar->name, len) && (cvar->flags & neededflags))
            Cvar_PrintHelp(cvar, cvar->name, true);
        else
            for (char **alias = cvar->aliases; alias && *alias; alias++)
                if (!strncasecmp (partial, *alias, len) && (cvar->flags & neededflags))
                    Cvar_PrintHelp(cvar, *alias, true);
 
        
}
 
static const char *Cvar_IsAutoCvar(cvar_t *var)
{
    int i;
    prvm_prog_t *prog;
    for (i = 0;i < PRVM_PROG_MAX;i++)
    {
        prog = &prvm_prog_list[i];
        if (prog->loaded && var->globaldefindex[i] >= 0)
            return prog->name;
    }
    return NULL;
}
 
static void Cvar_UpdateAutoCvar(cvar_t *var)
{
    int i;
    int j;
    const char *s;
    vec3_t v;
    prvm_prog_t *prog;
    for (i = 0;i < PRVM_PROG_MAX;i++)
    {
        prog = &prvm_prog_list[i];
        if (prog->loaded && var->globaldefindex[i] >= 0)
        {
            // MUST BE SYNCED WITH prvm_edict.c PRVM_Prog_Load
            switch(prog->globaldefs[var->globaldefindex[i]].type & ~DEF_SAVEGLOBAL)
            {
            case ev_float:
                PRVM_GLOBALFIELDFLOAT(prog->globaldefs[var->globaldefindex[i]].ofs) = var->value;
                break;
            case ev_vector:
                s = var->string;
                VectorClear(v);
                for (j = 0;j < 3;j++)
                {
                    while (*s && ISWHITESPACE(*s))
                        s++;
                    if (!*s)
                        break;
                    v[j] = atof(s);
                    while (!ISWHITESPACE(*s))
                        s++;
                    if (!*s)
                        break;
                }
                VectorCopy(v, PRVM_GLOBALFIELDVECTOR(prog->globaldefs[var->globaldefindex[i]].ofs));
                break;
            case ev_string:
                PRVM_ChangeEngineString(prog, var->globaldefindex_stringno[i], var->string);
                PRVM_GLOBALFIELDSTRING(prog->globaldefs[var->globaldefindex[i]].ofs) = var->globaldefindex_stringno[i];
                break;
            }
        }
    }
}
 
void Cvar_UpdateAllAutoCvars(cvar_state_t *cvars)
{
    cvar_t *var;
    for (var = cvars->vars ; var ; var = var->next)
        Cvar_UpdateAutoCvar(var);
}
 
void Cvar_Callback(cvar_t *var)
{
    if (var == NULL)
    {
        Con_Print(CON_WARN "Cvar_Callback: var == NULL\n");
        return;
    }
 
    if(var->callback)
        var->callback(var);
}
 
/*
============
Cvar_Set
============
*/
extern cvar_t sv_disablenotify;
static void Cvar_SetQuick_Internal (cvar_t *var, const char *value)
{
    qbool changed;
    size_t valuelen;
 
    changed = strcmp(var->string, value) != 0;
    // LadyHavoc: don't reallocate when there is no change
    if (!changed)
        goto cvar_callback;
 
    // LadyHavoc: don't reallocate when the buffer is the same size
    valuelen = strlen(value);
    if (!var->string || strlen(var->string) != valuelen)
    {
        Z_Free ((char *)var->string);   // free the old value string
 
        var->string = (char *)Z_Malloc (valuelen + 1);
    }
    memcpy ((char *)var->string, value, valuelen + 1);
    var->value = atof (var->string);
    var->integer = (int) var->value;
    if ((var->flags & CF_NOTIFY) && sv.active && !sv_disablenotify.integer)
        SV_BroadcastPrintf("\003^3Server cvar \"%s\" changed to \"%s\"\n", var->name, var->string);
#if 0
    // TODO: add infostring support to the server?
    if ((var->flags & CF_SERVERINFO) && changed && sv.active)
    {
        InfoString_SetValue(svs.serverinfo, sizeof(svs.serverinfo), var->name, var->string);
        if (sv.active)
        {
            MSG_WriteByte (&sv.reliable_datagram, svc_serverinfostring);
            MSG_WriteString (&sv.reliable_datagram, var->name);
            MSG_WriteString (&sv.reliable_datagram, var->string);
        }
    }
#endif
    if (var->flags & CF_USERINFO)
        CL_SetInfo(var->name, var->string, true, false, false, false);
 
    Cvar_UpdateAutoCvar(var);
 
cvar_callback:
    // Call the function stored in the cvar for bounds checking, cleanup, etc
    Cvar_Callback(var);
}
 
void Cvar_SetQuick (cvar_t *var, const char *value)
{
    if (var == NULL)
    {
        Con_Print(CON_WARN "Cvar_SetQuick: var == NULL\n");
        return;
    }
 
    if (!(var->flags & CF_REGISTERED) && !(var->flags & CF_ALLOCATED))
    {
        Con_Printf(CON_WARN "Warning: Cvar_SetQuick() cannot set unregistered cvar \"%s\"\n", var->name);
        return; // setting an unregistered engine cvar crashes
    }
 
    if (developer_extra.integer)
        Con_DPrintf("Cvar_SetQuick({\"%s\", \"%s\", %i, \"%s\"}, \"%s\");\n", var->name, var->string, var->flags, var->defstring, value);
 
    Cvar_SetQuick_Internal(var, value);
}
 
void Cvar_Set(cvar_state_t *cvars, const char *var_name, const char *value)
{
    cvar_t *var;
    var = Cvar_FindVar(cvars, var_name, ~0);
    if (var == NULL)
    {
        Con_Printf(CON_WARN "Cvar_Set: variable %s not found\n", var_name);
        return;
    }
    Cvar_SetQuick(var, value);
}
 
/*
============
Cvar_SetValue
============
*/
void Cvar_SetValueQuick(cvar_t *var, float value)
{
    char val[MAX_INPUTLINE];
 
    if ((float)((int)value) == value)
        dpsnprintf(val, sizeof(val), "%i", (int)value);
    else
        dpsnprintf(val, sizeof(val), "%f", value);
    Cvar_SetQuick(var, val);
}
 
void Cvar_SetValue(cvar_state_t *cvars, const char *var_name, float value)
{
    char val[MAX_INPUTLINE];
 
    if ((float)((int)value) == value)
        dpsnprintf(val, sizeof(val), "%i", (int)value);
    else
        dpsnprintf(val, sizeof(val), "%f", value);
    Cvar_Set(cvars, var_name, val);
}
 
void Cvar_RegisterCallback(cvar_t *variable, void (*callback)(cvar_t *))
{
    if (variable == NULL)
    {
        Con_Print(CON_WARN "Cvar_RegisterCallback: var == NULL\n");
        return;
    }
 
    if (!(variable->flags & cmd_local->cvars_flagsmask))
    {
        if (developer_extra.integer)
            Con_DPrintf("^6Cvar_RegisterCallback: rejecting cvar \"%s\"\n", variable->name);
        return;
    }
 
    variable->callback = callback;
}
 
void Cvar_RegisterVirtual(cvar_t *variable, const char *name )
{
    cvar_state_t *cvars = &cvars_all;
    cvar_hash_t *hash;
    unsigned hashindex;
 
    if (!(variable->flags & cmd_local->cvars_flagsmask))
    {
        if (developer_extra.integer)
            Con_DPrintf("^6Cvar_RegisterVirtual: rejecting cvar \"%s\" alias \"%s\"\n", variable->name, name);
        return;
    }
 
    if(!*name)
    {
        Con_Printf(CON_WARN "Cvar_RegisterVirtual: invalid virtual cvar name\n");
        return;
    }
 
    // check for overlap with a command
    if (Cmd_Exists(cmd_local, name))
    {
        Con_Printf(CON_WARN "Cvar_RegisterVirtual: %s is a command\n", name);
        return;
    }
 
    if(Cvar_FindVar(&cvars_all, name, 0))
    {
        Con_Printf(CON_WARN "Cvar_RegisterVirtual: %s is a cvar\n", name);
        return;
    }
 
    // Resize the variable->aliases list to have room for another entry and a null terminator.
    // This zero-pads when resizing, so we don't need to write the NULL terminator manually here.
    // Also if aliases is NULL this allocates fresh for the correct size, so it's fine to just do this.
    variable->aliases = (char **)Z_Realloc(variable->aliases, sizeof(char *) * (variable->aliases_size + 2));
    // Add the new alias, and increment the number of aliases in the list
    variable->aliases[variable->aliases_size++] = Z_strdup(name);
 
    // link to head of list in this hash table index
    hash = (cvar_hash_t *)Z_Malloc(sizeof(cvar_hash_t));
    hashindex = CRC_Block((const unsigned char *)name, strlen(name)) % CVAR_HASHSIZE;
    hash->next = cvars->hashtable[hashindex];
    cvars->hashtable[hashindex] = hash;
    hash->cvar = variable;
}
 
/*
============
Cvar_Link
 
Links a variable to the variable list and hashtable
============
*/
static void Cvar_Link(cvar_t *variable, cvar_state_t *cvars)
{
    cvar_t *current, *next;
    cvar_hash_t *hash;
    unsigned hashindex;
    /*
     * Link the variable in
     * alphanumerical order
     */
    for( current = NULL, next = cvars->vars ; next && strcmp( next->name, variable->name ) < 0 ; current = next, next = next->next )
        ;
    if(current)
        current->next = variable;
    else
        cvars->vars = variable;
    variable->next = next;
 
    // link to head of list in this hash table index
    hash = (cvar_hash_t *)Z_Malloc(sizeof(cvar_hash_t));
    hashindex = CRC_Block((const unsigned char *)variable->name, strlen(variable->name)) % CVAR_HASHSIZE;
    hash->next = cvars->hashtable[hashindex];
    hash->cvar = variable;
    cvars->hashtable[hashindex] = hash;
}
 
/*
============
Cvar_RegisterVariable
 
Adds a freestanding variable to the variable list.
============
*/
void Cvar_RegisterVariable (cvar_t *variable)
{
    cvar_state_t *cvars = &cvars_all;
    cvar_t *current, *cvar;
    int i;
 
    if (!(variable->flags & cmd_local->cvars_flagsmask))
    {
        if (developer_extra.integer)
            Con_DPrintf("^2Cvar_RegisterVariable: rejecting cvar \"%s\"\n", variable->name);
        return;
    }
 
    if (developer_extra.integer)
        Con_DPrintf("Cvar_RegisterVariable({\"%s\", \"%s\", %i});\n", variable->name, variable->string, variable->flags);
 
    // first check to see if it has already been defined
    cvar = Cvar_FindVar(cvars, variable->name, ~0);
    if (cvar)
    {
        if (cvar->flags & CF_ALLOCATED)
        {
            if (developer_extra.integer)
                Con_DPrintf("...  replacing existing allocated cvar {\"%s\", \"%s\", %i}\n", cvar->name, cvar->string, cvar->flags);
            // fixed variables replace allocated ones
            // (because the engine directly accesses fixed variables)
            // NOTE: this isn't actually used currently
            // (all cvars are registered before config parsing)
            variable->flags &= ~CF_ALLOCATED;
            // cvar->string is now owned by variable instead
            variable->string = cvar->string;
            variable->defstring = cvar->defstring;
            variable->value = atof (variable->string);
            variable->integer = (int) variable->value;
            // Preserve autocvar status.
            memcpy(variable->globaldefindex, cvar->globaldefindex, sizeof(variable->globaldefindex));
            memcpy(variable->globaldefindex_stringno, cvar->globaldefindex_stringno, sizeof(variable->globaldefindex_stringno));
            // replace cvar with this one...
            variable->next = cvar->next;
            if (cvars->vars == cvar)
            {
                // head of the list is easy to change
                cvars->vars = variable;
            }
            else
            {
                // otherwise find it somewhere in the list
                for (current = cvars->vars;current->next != cvar;current = current->next)
                    ;
                current->next = variable;
            }
 
            // get rid of old allocated cvar
            // (but not cvar->string and cvar->defstring, because we kept those)
            Z_Free((char *)cvar->name);
            Z_Free(cvar);
        }
        else
            Con_DPrintf("Can't register variable %s, already defined\n", variable->name);
        return;
    }
 
    // check for overlap with a command
    if (Cmd_Exists(cmd_local, variable->name))
    {
        Con_Printf(CON_WARN "Cvar_RegisterVariable: %s is a command\n", variable->name);
        return;
    }
 
    // copy the value off, because future sets will Z_Free it
    variable->name = Z_strdup(variable->name);
    variable->string = Z_strdup(variable->string);
    variable->defstring = Z_strdup(variable->string);
    variable->value = atof (variable->string);
    variable->integer = (int) variable->value;
    variable->aliases = NULL;
    variable->aliases_size = 0;
    variable->initstring = NULL;
 
    // Mark it as not an autocvar.
    for (i = 0;i < PRVM_PROG_MAX;i++)
        variable->globaldefindex[i] = -1;
 
    // Safe for Cvar_SetQuick()
    variable->flags |= CF_REGISTERED;
 
    Cvar_Link(variable, cvars);
}
 
/*
============
Cvar_Get
 
Adds a newly allocated variable to the variable list or sets its value.
============
*/
cvar_t *Cvar_Get(cvar_state_t *cvars, const char *name, const char *value, unsigned flags, const char *newdescription)
{
    cvar_t *cvar;
    int i;
 
    if (developer_extra.integer)
        Con_DPrintf("Cvar_Get(\"%s\", \"%s\", %i);\n", name, value, flags);
 
    // first check to see if it has already been defined
    cvar = Cvar_FindVar(cvars, name, ~0);
    if (cvar)
    {
        cvar->flags |= flags;
        Cvar_SetQuick_Internal (cvar, value);
        if(newdescription && (cvar->flags & CF_ALLOCATED))
        {
            if(cvar->description != cvar_dummy_description)
                Z_Free((char *)cvar->description);
 
            if(*newdescription)
                cvar->description = Z_strdup(newdescription);
            else
                cvar->description = cvar_dummy_description;
        }
        return cvar;
    }
 
    // check for pure evil
    if (!*name)
    {
        Con_Printf(CON_WARN "Cvar_Get: invalid variable name\n");
        return NULL;
    }
 
    // check for overlap with a command
    if (Cmd_Exists(cmd_local, name))
    {
        Con_Printf(CON_WARN "Cvar_Get: %s is a command\n", name);
        return NULL;
    }
 
    // allocate a new cvar, cvar name, and cvar string
    // TODO: factorize the following code with the one at the end of Cvar_RegisterVariable()
    // FIXME: these never get Z_Free'd
    cvar = (cvar_t *)Z_Malloc(sizeof(cvar_t));
    cvar->flags = flags | CF_ALLOCATED;
    cvar->name = Z_strdup(name);
    cvar->string = Z_strdup(value);
    cvar->defstring = Z_strdup(value);
    cvar->value = atof (cvar->string);
    cvar->integer = (int) cvar->value;
    cvar->aliases = NULL;
    cvar->aliases_size = 0;
    cvar->initstring = NULL;
 
    if(newdescription && *newdescription)
        cvar->description = Z_strdup(newdescription);
    else
        cvar->description = cvar_dummy_description; // actually checked by VM_cvar_type
 
    // Mark it as not an autocvar.
    for (i = 0;i < PRVM_PROG_MAX;i++)
        cvar->globaldefindex[i] = -1;
 
    Cvar_Link(cvar, cvars);
 
    return cvar;
}
 
static qbool Cvar_Delete(cvar_state_t *cvars, const char *name, const char *callername)
{
    cvar_t *cvar, *prev;
    cvar_hash_t **hashlinkptr, *oldhashlink;
    const char *progname;
 
    hashlinkptr = Cvar_FindVarLink(cvars, name, &prev, ~0);
    if(!hashlinkptr)
    {
        if (callername)
            Con_Printf("%s: cvar \"%s\" is not defined.\n", callername, name);
        return false;
    }
    cvar = (*hashlinkptr)->cvar;
 
    if(!(cvar->flags & CF_ALLOCATED))
    {
        if (callername)
            Con_Printf(CON_WARN "%s: engine cvar \"%s\" cannot be deleted!\n", callername, cvar->name);
        return false;
    }
    if ((progname = Cvar_IsAutoCvar(cvar)))
    {
        if (callername)
            Con_Printf(CON_WARN "%s: unable to delete cvar \"%s\", it is an autocvar used by running %s progs!\n", callername, cvar->name, progname);
        return false;
    }
 
    if(cvar == cvars->vars)
        cvars->vars = cvar->next;
    else
        prev->next = cvar->next;
 
    if(cvar->description != cvar_dummy_description)
        Z_Free((char *)cvar->description);
    Z_Free((char *)cvar->name);
    Z_Free((char *)cvar->string);
    Z_Free((char *)cvar->defstring);
    Z_Free(cvar);
 
    oldhashlink = *hashlinkptr;
    *hashlinkptr = (*hashlinkptr)->next;
    Z_Free(oldhashlink);
 
    return true;
}
 
qbool Cvar_Readonly (cvar_t *var, const char *cmd_name)
{
    if (var->flags & CF_READONLY)
    {
        Con_Print(CON_WARN);
        if(cmd_name)
            Con_Printf("%s: ",cmd_name);
        Con_Printf("%s is read-only\n", var->name);
        return true;
    }
    return false;
}
 
/*
============
Cvar_Command
 
Handles variable inspection and changing from the console
============
*/
qbool   Cvar_Command (cmd_state_t *cmd)
{
    cvar_state_t    *cvars = cmd->cvars;
    cvar_t          *v;
 
    // check variables
    v = Cvar_FindVar(cvars, Cmd_Argv(cmd, 0), (cmd->cvars_flagsmask));
    if (!v)
        return false;
 
    // perform a variable print or set
    if (Cmd_Argc(cmd) == 1)
    {
        Cvar_PrintHelp(v, Cmd_Argv(cmd, 0), true);
        return true;
    }
 
    if (developer_extra.integer)
        Con_DPrint("Cvar_Command: ");
 
    if(Cvar_Readonly(v, NULL))
        return true;
 
    Cvar_SetQuick(v, Cmd_Argv(cmd, 1));
    if (developer_extra.integer)
        Con_DPrint("\n");
    return true;
}
 
void Cvar_UnlockDefaults(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *var;
    // unlock the default values of all cvars
    for (var = cvars->vars ; var ; var = var->next)
        var->flags &= ~CF_DEFAULTSET;
}
 
void Cvar_LockDefaults_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *var;
    // lock in the default values of all cvars
    for (var = cvars->vars ; var ; var = var->next)
    {
        if (!(var->flags & CF_DEFAULTSET))
        {
            size_t alloclen;
 
            //Con_Printf("locking cvar %s (%s -> %s)\n", var->name, var->string, var->defstring);
            var->flags |= CF_DEFAULTSET;
            Z_Free((char *)var->defstring);
            alloclen = strlen(var->string) + 1;
            var->defstring = (char *)Z_Malloc(alloclen);
            memcpy((char *)var->defstring, var->string, alloclen);
        }
    }
}
 
void Cvar_SaveInitState(cvar_state_t *cvars)
{
    cvar_t *c;
 
    for (c = cvars->vars;c;c = c->next)
        if ((c->flags & (CF_PERSISTENT | CF_READONLY)) == 0)
            c->initstring = Z_strdup(c->string);
}
 
void Cvar_RestoreInitState(cvar_state_t *cvars)
{
    cvar_t *c, *cp;
 
    for (cp = cvars->vars; (c = cp);)
    {
        cp = c->next; // get next cvar now in case we delete this cvar
 
        if (c->initstring)
        {
            // restore this cvar, it existed at init
            Con_DPrintf("Cvar_RestoreInitState: Restoring cvar \"%s\"\n", c->name);
 
            /* bones_was_here: intentionally NOT restoring defstring in this function.
             * The only callsite, Host_LoadConfig_f, will re-exec quake.rc, default.cfg, etc.
             * Defaults are unlocked here, so Cvar_LockDefaults_f will reset the defstring.
             * This is more correct than restoring the defstring here
             * because a gamedir change could load configs that should change defaults.
             */
 
            Cvar_SetQuick(c, c->initstring);
            c->flags &= ~CF_DEFAULTSET;
        }
        else if (!(c->flags & (CF_PERSISTENT | CF_READONLY))) // cvars with those flags have no initstring AND may not be deleted or reset
        {
            // remove this cvar, it did not exist at init
            Con_DPrintf("Cvar_RestoreInitState: cvar \"%s\"", c->name);
            if (Cvar_Delete(cvars, c->name, NULL))
                Con_DPrint("deleted.\n");
            else
            {
                // In this case, at least reset it to the default.
                Con_DPrint("reset.\n");
                Cvar_SetQuick(c, c->defstring);
            }
        }
    }
}
 
void Cvar_ResetToDefaults_All_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *var;
    // restore the default values of all cvars
    for (var = cvars->vars ; var ; var = var->next)
    {
        if((var->flags & (CF_PERSISTENT | CF_READONLY)) == 0)
            Cvar_SetQuick(var, var->defstring);
    }
}
 
void Cvar_ResetToDefaults_NoSaveOnly_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *var;
    // restore the default values of all cvars
    for (var = cvars->vars ; var ; var = var->next)
    {
        if ((var->flags & (CF_PERSISTENT | CF_READONLY | CF_ARCHIVE)) == 0)
            Cvar_SetQuick(var, var->defstring);
    }
}
 
 
void Cvar_ResetToDefaults_SaveOnly_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *var;
    // restore the default values of all cvars
    for (var = cvars->vars ; var ; var = var->next)
    {
        if ((var->flags & (CF_PERSISTENT | CF_READONLY | CF_ARCHIVE)) == CF_ARCHIVE)
            Cvar_SetQuick(var, var->defstring);
    }
}
 
/*
============
Cvar_WriteVariables
 
Writes lines containing "set variable value" for all variables
with the archive flag set to true.
============
*/
void Cvar_WriteVariables (cvar_state_t *cvars, qfile_t *f)
{
    cvar_t  *var;
    char buf1[MAX_INPUTLINE], buf2[MAX_INPUTLINE];
 
    // don't save cvars that match their default value
    for (var = cvars->vars ; var ; var = var->next) {
        if ((var->flags & CF_ARCHIVE) && (strcmp(var->string, var->defstring) || ((var->flags & CF_ALLOCATED) && !(var->flags & CF_DEFAULTSET))))
        {
            Cmd_QuoteString(buf1, sizeof(buf1), var->name, "\"\\$", false);
            Cmd_QuoteString(buf2, sizeof(buf2), var->string, "\"\\$", false);
            FS_Printf(f, "%s\"%s\" \"%s\"\n", var->flags & CF_ALLOCATED ? "seta " : "", buf1, buf2);
        }
    }
}
 
// Added by EvilTypeGuy eviltypeguy@qeradiant.com
// 2000-01-09 CvarList command By Matthias "Maddes" Buecher, http://www.inside3d.com/qip/
/*
=========
Cvar_List
=========
*/
void Cvar_List_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *cvar;
    const char *partial;
    int count;
    qbool ispattern;
    char vabuf[1024];
 
    if (Cmd_Argc(cmd) > 1)
    {
        partial = Cmd_Argv(cmd, 1);
        ispattern = (strchr(partial, '*') || strchr(partial, '?'));
        if(!ispattern)
            partial = va(vabuf, sizeof(vabuf), "%s*", partial);
    }
    else
    {
        partial = va(vabuf, sizeof(vabuf), "*");
        ispattern = false;
    }
 
    count = 0;
    for (cvar = cvars->vars; cvar; cvar = cvar->next)
    {
        if (matchpattern_with_separator(cvar->name, partial, false, "", false))
        {
            Cvar_PrintHelp(cvar, cvar->name, true);
            count++;
        }
        for (char **alias = cvar->aliases; alias && *alias; alias++)
        {
            if (matchpattern_with_separator(*alias, partial, false, "", false))
            {
                Cvar_PrintHelp(cvar, *alias, true);
                count++;
            }
        }
    }
 
    if (Cmd_Argc(cmd) > 1)
    {
        if(ispattern)
            Con_Printf("%i cvar%s matching \"%s\"\n", count, (count > 1) ? "s" : "", partial);
        else
            Con_Printf("%i cvar%s beginning with \"%s\"\n", count, (count > 1) ? "s" : "", Cmd_Argv(cmd,1));
    }
    else
        Con_Printf("%i cvar(s)\n", count);
}
// 2000-01-09 CvarList command by Maddes
 
void Cvar_Set_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *cvar;
 
    // make sure it's the right number of parameters
    if (Cmd_Argc(cmd) < 3)
    {
        Con_Printf("Set: wrong number of parameters, usage: set <variablename> <value> [<description>]\n");
        return;
    }
 
    // check if it's read-only
    cvar = Cvar_FindVar(cvars, Cmd_Argv(cmd, 1), ~0);
    if (cvar)
        if(Cvar_Readonly(cvar,"Set"))
            return;
 
    if (developer_extra.integer)
        Con_DPrint("Set: ");
 
    // all looks ok, create/modify the cvar
    Cvar_Get(cvars, Cmd_Argv(cmd, 1), Cmd_Argv(cmd, 2), cmd->cvars_flagsmask, Cmd_Argc(cmd) > 3 ? Cmd_Argv(cmd, 3) : NULL);
}
 
void Cvar_SetA_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    cvar_t *cvar;
 
    // make sure it's the right number of parameters
    if (Cmd_Argc(cmd) < 3)
    {
        Con_Printf("SetA: wrong number of parameters, usage: seta <variablename> <value> [<description>]\n");
        return;
    }
 
    // check if it's read-only
    cvar = Cvar_FindVar(cvars, Cmd_Argv(cmd, 1), ~0);
    if (cvar)
        if(Cvar_Readonly(cvar,"SetA"))
            return;
 
    if (developer_extra.integer)
        Con_DPrint("SetA: ");
 
    // all looks ok, create/modify the cvar
    Cvar_Get(cvars, Cmd_Argv(cmd, 1), Cmd_Argv(cmd, 2), cmd->cvars_flagsmask | CF_ARCHIVE, Cmd_Argc(cmd) > 3 ? Cmd_Argv(cmd, 3) : NULL);
}
 
void Cvar_Del_f(cmd_state_t *cmd)
{
    cvar_state_t *cvars = cmd->cvars;
    int i;
 
    if(Cmd_Argc(cmd) < 2)
    {
        Con_Printf("%s: wrong number of parameters, usage: unset <variablename1> [<variablename2> ...]\n", Cmd_Argv(cmd, 0));
        return;
    }
    for(i = 1; i < Cmd_Argc(cmd); ++i)
        Cvar_Delete(cvars, Cmd_Argv(cmd, i), Cmd_Argv(cmd, 0));
}
 
#ifdef FILLALLCVARSWITHRUBBISH
void Cvar_FillAll_f(cmd_state_t *cmd)
{
    char *buf, *p, *q;
    int n, i;
    cvar_t *var;
    qbool verify;
    if(Cmd_Argc(cmd) != 2)
    {
        Con_Printf("Usage: %s length to plant rubbish\n", Cmd_Argv(cmd, 0));
        Con_Printf("Usage: %s -length to verify that the rubbish is still there\n", Cmd_Argv(cmd, 0));
        return;
    }
    n = atoi(Cmd_Argv(cmd, 1));
    verify = (n < 0);
    if(verify)
        n = -n;
    buf = Z_Malloc(n + 1);
    buf[n] = 0;
    for(var = cvars->vars; var; var = var->next)
    {
        for(i = 0, p = buf, q = var->name; i < n; ++i)
        {
            *p++ = *q++;
            if(!*q)
                q = var->name;
        }
        if(verify && strcmp(var->string, buf))
        {
            Con_Printf("\n%s does not contain the right rubbish, either this is the first run or a possible overrun was detected, or something changed it intentionally; it DOES contain: %s\n", var->name, var->string);
        }
        Cvar_SetQuick(var, buf);
    }
    Z_Free(buf);
}
#endif /* FILLALLCVARSWITHRUBBISH */