// command.cpp: implements the parsing and execution of a tiny script language which
// is largely backwards compatible with the quake console language.
#include "cube.h"
enum { ID_VAR, ID_COMMAND, ID_ALIAS };
struct ident
{
int type; // one of ID_* above
char *name;
int min, max; // ID_VAR
int *storage; // ID_VAR
void (*fun)(); // ID_VAR, ID_COMMAND
int narg; // ID_VAR, ID_COMMAND
char *action; // ID_ALIAS
bool persist;
};
void itoa(char *s, int i) { sprintf_s(s)("%d", i); };
char *exchangestr(char *o, char *n) { gp()->deallocstr(o); return newstring(n); };
hashtable<ident> *idents = NULL; // contains ALL vars/commands/aliases
void alias(char *name, char *action)
{
ident *b = idents->access(name);
if(!b)
{
name = newstring(name);
ident b = { ID_ALIAS, name, 0, 0, 0, 0, 0, newstring(action), true };
idents->access(name, &b);
}
else
{
if(b->type==ID_ALIAS) b->action = exchangestr(b->action, action);
else conoutf("cannot redefine builtin %s with an alias", name);
};
};
COMMAND(alias, ARG_2STR);
// variable's and commands are registered through globals, see cube.h
int variable(char *name, int min, int cur, int max, int *storage, void (*fun)(), bool persist)
{
if(!idents) idents = new hashtable<ident>;
ident v = { ID_VAR, name, min, max, storage, fun, 0, 0, persist };
idents->access(name, &v);
return cur;
};
void setvar(char *name, int i) { *idents->access(name)->storage = i; };
int getvar(char *name) { return *idents->access(name)->storage; };
bool identexists(char *name) { return idents->access(name)!=NULL; };
char *getalias(char *name)
{
ident *i = idents->access(name);
return i && i->type==ID_ALIAS ? i->action : NULL;
};
bool addcommand(char *name, void (*fun)(), int narg)
{
if(!idents) idents = new hashtable<ident>;
ident c = { ID_COMMAND, name, 0, 0, 0, fun, narg, 0, false };
idents->access(name, &c);
return false;
};
char *parseexp(char *&p, int right) // parse any nested set of () or []
{
int left = *p++;
char *word = p;
for(int brak = 1; brak; )
{
int c = *p++;
if(c=='\r') *(p-1) = ' '; // hack
if(c==left) brak++;
else if(c==right) brak--;
else if(!c) { p--; conoutf("missing \"%c\"", right); return NULL; };
};
char *s = newstring(word, p-word-1);
if(left=='(')
{
string t;
itoa(t, execute(s)); // evaluate () exps directly, and substitute result
s = exchangestr(s, t);
};
return s;
};
char *parseword(char *&p) // parse single argument, including expressions
{
p += strspn(p, " \t\r");
if(p[0]=='/' && p[1]=='/') p += strcspn(p, "\n\0");
if(*p=='\"')
{
p++;
char *word = p;
p += strcspn(p, "\"\r\n\0");
char *s = newstring(word, p-word);
if(*p=='\"') p++;
return s;
};
if(*p=='(') return parseexp(p, ')');
if(*p=='[') return parseexp(p, ']');
char *word = p;
p += strcspn(p, "; \t\r\n\0");
if(p-word==0) return NULL;
return newstring(word, p-word);
};
char *lookup(char *n) // find value of ident referenced with $ in exp
{
ident *id = idents->access(n+1);
if(id) switch(id->type)
{
case ID_VAR: string t; itoa(t, *(id->storage)); return exchangestr(n, t);
case ID_ALIAS: return exchangestr(n, id->action);
};
conoutf("unknown alias lookup: %s", n+1);
return n;
};
int execute(char *p, bool isdown) // all evaluation happens here, recursively
{
const int MAXWORDS = 25; // limit, remove
char *w[MAXWORDS];
int val = 0;
for(bool cont = true; cont;) // for each ; seperated statement
{
int numargs = MAXWORDS;
loopi(MAXWORDS) // collect all argument values
{
w[i] = "";
if(i>numargs) continue;
char *s = parseword(p); // parse and evaluate exps
if(!s) { numargs = i; s = ""; };
if(*s=='$') s = lookup(s); // substitute variables
w[i] = s;
};
p += strcspn(p, ";\n\0");
cont = *p++!=0; // more statements if this isn't the end of the string
char *c = w[0];
if(*c=='/') c++; // strip irc-style command prefix
if(!*c) continue; // empty statement
ident *id = idents->access(c);
if(!id)
{
val = ATOI(c);
if(!val && *c!='0') conoutf("unknown command: %s", c);
}
else switch(id->type)
{
case ID_COMMAND: // game defined commands
switch(id->narg) // use very ad-hoc function signature, and just call it
{
case ARG_1INT: if(isdown) ((void (__cdecl *)(int))id->fun)(ATOI(w[1])); break;
case ARG_2INT: if(isdown) ((void (__cdecl *)(int, int))id->fun)(ATOI(w[1]), ATOI(w[2])); break;
case ARG_3INT: if(isdown) ((void (__cdecl *)(int, int, int))id->fun)(ATOI(w[1]), ATOI(w[2]), ATOI(w[3])); break;
case ARG_4INT: if(isdown) ((void (__cdecl *)(int, int, int, int))id->fun)(ATOI(w[1]), ATOI(w[2]), ATOI(w[3]), ATOI(w[4])); break;
case ARG_NONE: if(isdown) ((void (__cdecl *)())id->fun)(); break;
case ARG_1STR: if(isdown) ((void (__cdecl *)(char *))id->fun)(w[1]); break;
case ARG_2STR: if(isdown) ((void (__cdecl *)(char *, char *))id->fun)(w[1], w[2]); break;
case ARG_3STR: if(isdown) ((void (__cdecl *)(char *, char *, char*))id->fun)(w[1], w[2], w[3]); break;
case ARG_5STR: if(isdown) ((void (__cdecl *)(char *, char *, char*, char*, char*))id->fun)(w[1], w[2], w[3], w[4], w[5]); break;
case ARG_DOWN: ((void (__cdecl *)(bool))id->fun)(isdown); break;
case ARG_DWN1: ((void (__cdecl *)(bool, char *))id->fun)(isdown, w[1]); break;
case ARG_1EXP: if(isdown) val = ((int (__cdecl *)(int))id->fun)(execute(w[1])); break;
case ARG_2EXP: if(isdown) val = ((int (__cdecl *)(int, int))id->fun)(execute(w[1]), execute(w[2])); break;
case ARG_1EST: if(isdown) val = ((int (__cdecl *)(char *))id->fun)(w[1]); break;
case ARG_2EST: if(isdown) val = ((int (__cdecl *)(char *, char *))id->fun)(w[1], w[2]); break;
case ARG_VARI: if(isdown)
{
string r; // limit, remove
r[0] = 0;
for(int i = 1; i<numargs; i++)
{
strcat_s(r, w[i]); // make string-list out of all arguments
if(i==numargs-1) break;
strcat_s(r, " ");
};
((void (__cdecl *)(char *))id->fun)(r);
break;
}
};
break;
case ID_VAR: // game defined variabled
if(isdown)
{
if(!w[1][0]) conoutf("%s = %d", c, *id->storage); // var with no value just prints its current value
else
{
if(id->min>id->max)
{
conoutf("variable is read-only");
}
else
{
int i1 = ATOI(w[1]);
if(i1<id->min || i1>id->max)
{
i1 = i1<id->min ? id->min : id->max; // clamp to valid range
conoutf("valid range for %s is %d..%d", c, id->min, id->max);
}
*id->storage = i1;
};
if(id->fun) ((void (__cdecl *)())id->fun)(); // call trigger function if available
};
};
break;
case ID_ALIAS: // alias, also used as functions and (global) variables
for(int i = 1; i<numargs; i++)
{
sprintf_sd(t)("arg%d", i); // set any arguments as (global) arg values so functions can access them
alias(t, w[i]);
};
char *action = newstring(id->action); // create new string here because alias could rebind itself
val = execute(action, isdown);
gp()->deallocstr(action);
break;
};
loopj(numargs) gp()->deallocstr(w[j]);
};
return val;
};
// tab-completion of all idents
int completesize = 0, completeidx = 0;
void resetcomplete() { completesize = 0; };
void complete(char *s)
{
if(*s!='/')
{
string t;
strcpy_s(t, s);
strcpy_s(s, "/");
strcat_s(s, t);
};
if(!s[1]) return;
if(!completesize) { completesize = (int)strlen(s)-1; completeidx = 0; };
int idx = 0;
enumerate(idents, ident *, id,
if(strncmp(id->name, s+1, completesize)==0 && idx++==completeidx)
{
strcpy_s(s, "/");
strcat_s(s, id->name);
};
);
completeidx++;
if(completeidx>=idx) completeidx = 0;
};
bool execfile(char *cfgfile)
{
string s;
strcpy_s(s, cfgfile);
char *buf = loadfile(path(s), NULL);
if(!buf) return false;
execute(buf);
free(buf);
return true;
};
void exec(char *cfgfile)
{
if(!execfile(cfgfile)) conoutf("could not read \"%s\"", cfgfile);
};
void writecfg()
{
FILE *f = fopen("config.cfg", "w");
if(!f) return;
fprintf(f, "// automatically written on exit, do not modify\n// delete this file to have defaults.cfg overwrite these settings\n// modify settings in game, or put settings in autoexec.cfg to override anything\n\n");
writeclientinfo(f);
fprintf(f, "\n");
enumerate(idents, ident *, id,
if(id->type==ID_VAR && id->persist)
{
fprintf(f, "%s %d\n", id->name, *id->storage);
};
);
fprintf(f, "\n");
writebinds(f);
fprintf(f, "\n");
enumerate(idents, ident *, id,
if(id->type==ID_ALIAS && !strstr(id->name, "nextmap_"))
{
fprintf(f, "alias \"%s\" [%s]\n", id->name, id->action);
};
);
fclose(f);
};
COMMAND(writecfg, ARG_NONE);
// below the commands that implement a small imperative language. thanks to the semantics of
// () and [] expressions, any control construct can be defined trivially.
void intset(char *name, int v) { string b; itoa(b, v); alias(name, b); };
void ifthen(char *cond, char *thenp, char *elsep) { execute(cond[0]!='0' ? thenp : elsep); };
void loopa(char *times, char *body) { int t = atoi(times); loopi(t) { intset("i", i); execute(body); }; };
void whilea(char *cond, char *body) { while(execute(cond)) execute(body); }; // can't get any simpler than this :)
void onrelease(bool on, char *body) { if(!on) execute(body); };
void concat(char *s) { alias("s", s); };
void concatword(char *s)
{
for(char *a = s, *b = s; *a = *b; b++) if(*a!=' ') a++;
concat(s);
};
int listlen(char *a)
{
if(!*a) return 0;
int n = 0;
while(*a) if(*a++==' ') n++;
return n+1;
};
void at(char *s, char *pos)
{
int n = atoi(pos);
loopi(n) s += strspn(s += strcspn(s, " \0"), " ");
s[strcspn(s, " \0")] = 0;
concat(s);
};
COMMANDN(loop, loopa, ARG_2STR);
COMMANDN(while, whilea, ARG_2STR);
COMMANDN(if, ifthen, ARG_3STR);
COMMAND(onrelease, ARG_DWN1);
COMMAND(exec, ARG_1STR);
COMMAND(concat, ARG_VARI);
COMMAND(concatword, ARG_VARI);
COMMAND(at, ARG_2STR);
COMMAND(listlen, ARG_1EST);
int add(int a, int b) { return a+b; }; COMMANDN(+, add, ARG_2EXP);
int mul(int a, int b) { return a*b; }; COMMANDN(*, mul, ARG_2EXP);
int sub(int a, int b) { return a-b; }; COMMANDN(-, sub, ARG_2EXP);
int divi(int a, int b) { return b ? a/b : 0; }; COMMANDN(div, divi, ARG_2EXP);
int mod(int a, int b) { return b ? a%b : 0; }; COMMAND(mod, ARG_2EXP);
int equal(int a, int b) { return (int)(a==b); }; COMMANDN(=, equal, ARG_2EXP);
int lt(int a, int b) { return (int)(a<b); }; COMMANDN(<, lt, ARG_2EXP);
int gt(int a, int b) { return (int)(a>b); }; COMMANDN(>, gt, ARG_2EXP);
int strcmpa(char *a, char *b) { return strcmp(a,b)==0; }; COMMANDN(strcmp, strcmpa, ARG_2EST);
int rndn(int a) { return a>0 ? rnd(a) : 0; }; COMMANDN(rnd, rndn, ARG_1EXP);
int explastmillis() { return lastmillis; }; COMMANDN(millis, explastmillis, ARG_1EXP);