static void whilestat (LexState *ls, int line) {
/* whilestat -> WHILE cond DO block END */
FuncState *fs = ls->fs;
int whileinit;
int condexit;
BlockCnt bl;
luaX_next(ls); /* skip WHILE */
whileinit = luaK_getlabel(fs);
condexit = cond(ls);
enterblock(fs, &bl, 1);
checknext(ls, TK_DO);
block(ls);
luaK_patchlist(fs, luaK_jump(fs), whileinit);
check_match(ls, TK_END, TK_WHILE, line);
leaveblock(fs);
luaK_patchtohere(fs, condexit); /* false conditions finish the loop */
}
static void casestat (LexState *ls, expdesc *v) {
FuncState *fs = ls->fs;
expdesc v2;
int nargs, base;
/* do not set base to 0 for if case is used in (local) loops, it does not work properly */
base = fs->freereg;
luaK_exp2nextreg(fs, v);
nargs = explist1(ls, &v2); /* put every value into a register */
luaK_exp2nextreg(fs, &v2);
codecompcase(fs, base, nargs+1, v);
fs->freereg -= nargs+1; /* free all registers */
if (v->k == VNIL) v->k = VFALSE;
luaK_goiftrue(fs, v);
luaK_patchtohere(fs, v->t);
checknext(ls, TK_THEN);
block(ls);
}
static void recfield (LexState *ls, struct ConsControl *cc) {
/* recfield -> (NAME | `['exp1`]') = exp1 */
FuncState *fs = ls->fs;
int reg = ls->fs->freereg;
expdesc key, val;
int rkkey;
if (ls->t.token == TK_NAME) {
luaY_checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
checkname(ls, &key);
}
else /* ls->t.token == '[' */
yindex(ls, &key);
cc->nh++;
checknext(ls, '=');
rkkey = luaK_exp2RK(fs, &key);
expr(ls, &val);
luaK_codeABC(fs, OP_SETTABLE, cc->t->u.s.info, rkkey, luaK_exp2RK(fs, &val));
fs->freereg = reg; /* free registers */
}
static void forbody (LexState *ls, int base, int line, int nvars, int isnum) {
/* forbody -> DO block */
BlockCnt bl;
FuncState *fs = ls->fs;
int prep, endfor;
adjustlocalvars(ls, 3); /* control variables */
checknext(ls, TK_DO);
prep = isnum ? luaK_codeAsBx(fs, OP_FORPREP, base, NO_JUMP) : luaK_jump(fs);
enterblock(fs, &bl, 0); /* scope for declared variables */
adjustlocalvars(ls, nvars);
luaK_reserveregs(fs, nvars);
block(ls);
leaveblock(fs); /* end of scope for declared variables */
luaK_patchtohere(fs, prep);
endfor = (isnum) ? luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP) :
luaK_codeABC(fs, OP_TFORLOOP, base, 0, nvars);
luaK_fixline(fs, line); /* pretend that `OP_FOR' starts the loop */
luaK_patchlist(fs, (isnum ? endfor : luaK_jump(fs)), prep + 1);
}
static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
expdesc e;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
"variables in assignment");
assignment(ls, &nv, nvars+1);
}
else { /* assignment -> `=' explist1 */
int nexps;
/* hook for inc_assignment */
if(nvars==1) {
switch(ls->t.token) {
case '+': case '-': case '*': case '/': case TK_CONCAT:
inc_assignment(ls,lh);
/* If you're using Shook's table unpack patch, return 0 here.*/
return;
}
}
checknext(ls, '=');
nexps = explist1(ls, &e);
if (nexps != nvars) {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
else {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
return; /* avoid default */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
luaK_storevar(ls->fs, &lh->v, &e);
}
static void inc_assignment(LexState *ls, struct LHS_assign *lh) {
BinOpr op = getbinopr(ls->t.token);
FuncState * fs=ls->fs;
expdesc e, v2;
/* reserve all registers needed by the lvalue */
luaK_reserveregs(fs,fs->freereg-fs->nactvar);
luaX_next(ls);
checknext(ls, '=');
enterlevel(ls);
e = lh->v;
luaK_infix(fs,op,&e);
/* we only match one expr(), not a full explist(),
so "a+=2,2" will be a parse error. */
expr(ls,&v2);
luaK_posfix(fs, op, &e, &v2);
leavelevel(ls);
luaK_exp2nextreg(fs,&e);
luaK_setoneret(ls->fs, &e);
luaK_storevar(ls->fs, &lh->v, &e);
}
static void forlist (LexState *ls, TString *indexname) {
/* forlist -> NAME {,NAME} IN explist1 forbody */
FuncState *fs = ls->fs;
expdesc e;
int nvars = 0;
int line;
int base = fs->freereg;
/* create control variables */
new_localvarliteral(ls, "(for generator)", nvars++);
new_localvarliteral(ls, "(for state)", nvars++);
new_localvarliteral(ls, "(for control)", nvars++);
/* create declared variables */
new_localvar(ls, indexname, nvars++);
while (testnext(ls, ','))
new_localvar(ls, str_checkname(ls), nvars++);
checknext(ls, TK_IN);
line = ls->linenumber;
adjust_assign(ls, 3, explist1(ls, &e), &e);
luaK_checkstack(fs, 3); /* extra space to call generator */
forbody(ls, base, line, nvars - 3, 0);
}
static void constructor (LexState *ls, expdesc *t) {
/* constructor -> ?? */
FuncState *fs = ls->fs;
int line = ls->linenumber;
int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
struct ConsControl cc;
cc.na = cc.nh = cc.tostore = 0;
cc.t = t;
init_exp(t, VRELOCABLE, pc);
init_exp(&cc.v, VVOID, 0); /* no value (yet) */
luaK_exp2nextreg(ls->fs, t); /* fix it at stack top (for gc) */
checknext(ls, '{');
do {
lua_assert(cc.v.k == VVOID || cc.tostore > 0);
if (ls->t.token == '}') break;
closelistfield(fs, &cc);
switch(ls->t.token) {
case TK_NAME: { /* may be listfields or recfields */
luaX_lookahead(ls);
if (ls->lookahead.token != '=') /* expression? */
listfield(ls, &cc);
else
recfield(ls, &cc);
break;
}
case '[': { /* constructor_item -> recfield */
recfield(ls, &cc);
break;
}
default: { /* constructor_part -> listfield */
listfield(ls, &cc);
break;
}
}
} while (testnext(ls, ',') || testnext(ls, ';'));
check_match(ls, '}', '{', line);
lastlistfield(fs, &cc);
SETARG_B(fs->f->code[pc], luaO_int2fb(cc.na)); /* set initial array size */
SETARG_C(fs->f->code[pc], luaO_int2fb(cc.nh)); /* set initial table size */
}
static void assignment(LexState* ls, struct LHS_assign* lh, int nvars)
{
expdesc e;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) /* assignment -> `,' primaryexp assignment */
{
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
"variables in assignment");
assignment(ls, &nv, nvars + 1);
}
else /* assignment -> `=' explist1 */
{
int nexps;
checknext(ls, '=');
nexps = explist1(ls, &e);
if (nexps != nvars)
{
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
else
{
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
return; /* avoid default */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg - 1); /* default assignment */
luaK_storevar(ls->fs, &lh->v, &e);
}
static void constructor (LexState *ls, expdesc *t) {
/* constructor -> ?? */
FuncState *fs = ls->fs;
int line = ls->linenumber;
int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
struct ConsControl cc;
cc.na = cc.nh = cc.tostore = 0;
cc.t = t;
init_exp(t, VRELOCABLE, pc);
init_exp(&cc.v, VVOID, 0); /* no value (yet) */
luaK_exp2nextreg(ls->fs, t); /* fix it at stack top (for gc) */
checknext(ls, '{');
#if LUA_OPTIONAL_COMMA
for (;;) {
#else
do {
#endif /* LUA_OPTIONAL_COMMA */
lua_assert(cc.v.k == VVOID || cc.tostore > 0);
if (ls->t.token == '}') break;
closelistfield(fs, &cc);
switch(ls->t.token) {
case TK_NAME: { /* may be listfields or recfields */
luaX_lookahead(ls);
if (ls->lookahead.token != '=') /* expression? */
listfield(ls, &cc);
else
recfield(ls, &cc);
break;
}
case '[': { /* constructor_item -> recfield */
recfield(ls, &cc);
break;
}
default: { /* constructor_part -> listfield */
listfield(ls, &cc);
break;
}
}
#if LUA_OPTIONAL_COMMA
if (ls->t.token == ',' || ls->t.token == ';')
next(ls);
else if (ls->t.token == '}')
break;
}
#else
} while (testnext(ls, ',') || testnext(ls, ';'));
#endif /* LUA_OPTIONAL_COMMA */
check_match(ls, '}', '{', line);
lastlistfield(fs, &cc);
SETARG_B(fs->f->code[pc], luaO_int2fb(cc.na)); /* set initial array size */
SETARG_C(fs->f->code[pc], luaO_int2fb(cc.nh)); /* set initial table size */
}
/* }====================================================================== */
static void parlist (LexState *ls) {
/* parlist -> [ param { `,' param } ] */
FuncState *fs = ls->fs;
Proto *f = fs->f;
int nparams = 0;
f->is_vararg = 0;
if (ls->t.token != ')') { /* is `parlist' not empty? */
do {
switch (ls->t.token) {
case TK_NAME: { /* param -> NAME */
new_localvar(ls, str_checkname(ls), nparams++);
break;
}
case TK_DOTS: { /* param -> `...' */
luaX_next(ls);
#if defined(LUA_COMPAT_VARARG)
/* use `arg' as default name */
new_localvarliteral(ls, "arg", nparams++);
f->is_vararg = VARARG_HASARG | VARARG_NEEDSARG;
#endif
f->is_vararg |= VARARG_ISVARARG;
break;
}
default: luaX_syntaxerror(ls, "<name> or " LUA_QL("...") " expected");
}
} while (!f->is_vararg && testnext(ls, ','));
}
adjustlocalvars(ls, nparams);
f->numparams = cast_byte(fs->nactvar - (f->is_vararg & VARARG_HASARG));
luaK_reserveregs(fs, fs->nactvar); /* reserve register for parameters */
}
static void trystat (LexState *ls, int line) {
/* trystat -> TRY block CATCH err DO block END */
FuncState *fs = ls->fs;
BlockCnt bl;
int base, pc, escapelist = NO_JUMP;
luaX_next(ls);
enterblock(fs, &bl, 2); /* try block */
base = fs->freereg;
new_localvarliteral(ls, "(error obj)", 0);
adjustlocalvars(ls, 1); /* error object */
luaK_reserveregs(fs, 1);
pc = luaK_codeAsBx(fs, OP_TRY, base, NO_JUMP);
chunk(ls);
if (ls->t.token == TK_CATCH) {
TString *varname;
int errobj;
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
luaK_concat(fs, &escapelist, luaK_jump(fs));
SET_OPCODE(fs->f->code[pc], OP_TRYCATCH); /* change it to TRYCATCH */
luaK_patchtohere(fs, pc);
bl.isbreakable = 0;
// local err
luaX_next(ls); /* skip `catch' */
varname = str_checkname(ls); /* first variable name */
// do
checknext(ls, TK_DO);
errobj = fs->freereg;
new_localvar(ls, varname, 0);
adjustlocalvars(ls, 1);
luaK_reserveregs(fs, 1);
luaK_codeABC(fs, OP_MOVE, errobj, base, 0);
block(ls);
} else if (ls->t.token == TK_FINALLY) {
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
luaK_concat(fs, &escapelist, luaK_jump(fs));
SET_OPCODE(fs->f->code[pc], OP_TRYFIN); /* change it to TRYFIN */
luaK_patchtohere(fs, pc);
bl.isbreakable = 3;
luaX_next(ls); /* skip 'finally' */
block(ls);
luaK_codeABC(fs, OP_RETFIN, base, 0, 0); /* OP_ENDFIN jump to the return point */
} else {
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
luaK_concat(fs, &escapelist, pc);
}
leaveblock(fs);
luaK_patchtohere(fs, escapelist);
check_match(ls, TK_END, TK_TRY, line);
}
isearch(f, n)
{
int status; /* Search status */
int col; /* prompt column */
register int cpos; /* character number in search string */
register int c; /* current input character */
char pat_save[NPAT]; /* Saved copy of the old pattern str */
LINE *curline; /* Current line on entry */
int curoff; /* Current offset on entry */
int init_direction; /* The initial search direction */
/* Initialize starting conditions */
cmd_reexecute = -1; /* We're not re-executing (yet?) */
cmd_offset = 0; /* Start at the beginning of the buff */
cmd_buff[0] = '\0'; /* Init the command buffer */
strncpy (pat_save, pat, NPAT); /* Save the old pattern string */
curline = curwp->w_dotp; /* Save the current line pointer */
curoff = curwp->w_doto; /* Save the current offset */
init_direction = n; /* Save the initial search direction */
/* This is a good place to start a re-execution: */
start_over:
/* ask the user for the text of a pattern */
col = promptpattern("ISearch: "); /* Prompt, remember the col */
cpos = 0; /* Start afresh */
status = TRUE; /* Assume everything's cool */
/*
Get the first character in the pattern. If we get an initial Control-S
or Control-R, re-use the old search string and find the first occurrence
*/
c = get_char(); /* Get the first character */
if ((c == IS_FORWARD) ||
(c == IS_REVERSE) ||
(c == IS_VMSFORW)) /* Reuse old search string? */
{
for (cpos = 0; pat[cpos] != 0; cpos++) /* Yup, find the length */
col = echochar(pat[cpos],col); /* and re-echo the string */
if (c == IS_REVERSE) { /* forward search? */
n = -1; /* No, search in reverse */
backchar (TRUE, 1); /* Be defensive about EOB */
} else
n = 1; /* Yes, search forward */
status = scanmore(pat,n,status); /* Do the search */
c = get_char (); /* Get another character */
}
/* Top of the per character loop */
for (;;) /* ISearch per character loop */
{
/* Check for magic characters first: */
/* Most cases here change the search */
switch (c) /* dispatch on the input char */
{
case IS_ABORT: /* If abort search request */
return(FALSE); /* Quit searching again */
case IS_REVERSE: /* If backward search */
case IS_FORWARD: /* If forward search */
case IS_VMSFORW: /* of either flavor */
if (c == IS_REVERSE) /* If reverse search */
n = -1; /* Set the reverse direction */
else /* Otherwise, */
n = 1; /* go forward */
status = scanmore(pat,n,TRUE); /* Start the search again */
c = get_char (); /* Get the next char */
continue; /* Go continue with the search*/
case IS_QUIT: /* Want to quit searching? */
return (TRUE); /* Quit searching now */
case IS_NEWLINE: /* Carriage return */
c = '\n'; /* Make it a new line */
break; /* Make sure we use it */
case IS_QUOTE: /* Quote character */
case IS_VMSQUOTE: /* of either variety */
c = get_char (); /* Get the next char */
case IS_TAB: /* Generically allowed */
case '\n': /* controlled characters */
break; /* Make sure we use it */
case IS_BACKSP: /* If a backspace: */
case IS_RUBOUT: /* or if a Rubout: */
if (cmd_offset <= 1) /* Anything to delete? */
return (TRUE); /* No, just exit */
--cmd_offset; /* Back up over the Rubout */
cmd_buff[--cmd_offset] = '\0'; /* Yes, delete last char */
curwp->w_dotp = curline; /* Reset the line pointer */
curwp->w_doto = curoff; /* and the offset */
n = init_direction; /* Reset the search direction */
strncpy (pat, pat_save, NPAT); /* Restore the old search str */
cmd_reexecute = 0; /* Start the whole mess over */
goto start_over; /* Let it take care of itself */
/* Presumably a quasi-normal character comes here */
default: /* All other chars */
if (c < ' ') /* Is it printable? */
{ /* Nope. */
reeat (c); /* Re-eat the char */
return (TRUE); /* And return the last status */
}
} /* Switch */
/* I guess we got something to search for, so search for it */
pat[cpos++] = c; /* put the char in the buffer */
if (cpos >= NPAT) /* too many chars in string? */
{ /* Yup. Complain about it */
mlwrite("? Search string too long");
return(TRUE); /* Return an error */
}
pat[cpos] = 0; /* null terminate the buffer */
col = echochar(c,col); /* Echo the character */
if (!status) { /* If we lost last time */
(*term.t_putchar)(BELL); /* Feep again */
(*term.t_flush)(); /* see that the feep feeps */
} else /* Otherwise, we must have won*/
if (!(status = checknext(c,pat,n,status))) /* See if match */
status = scanmore(pat,n,TRUE); /* or find the next match */
c = get_char (); /* Get the next char */
} /* for {;;} */
}
