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authorManoj Srivastava <srivasta@debian.org>2020-05-22 19:57:41 -0700
committerManoj Srivastava <srivasta@debian.org>2020-05-22 20:02:19 -0700
commitc3d2579ad8d7eb33059aa8fdbaf5b564411a57f2 (patch)
tree1570cda0676fdcf4171a69a7fe313c1b89a52b0c /src/lua/lparser.c
parent986b7742bf244b4073ecca0723615f70be8a1ab6 (diff)
parent4e9b9c402ed95bf9a17fd6d795bc49bb4128a6fa (diff)
Merge branch 'upstream' into debian-cmake-fixes
Diffstat (limited to 'src/lua/lparser.c')
-rw-r--r--src/lua/lparser.c1129
1 files changed, 0 insertions, 1129 deletions
diff --git a/src/lua/lparser.c b/src/lua/lparser.c
deleted file mode 100644
index 1ac1f37b..00000000
--- a/src/lua/lparser.c
+++ /dev/null
@@ -1,1129 +0,0 @@
-/*
-** $Id: lparser.c,v 1.8 2004/06/04 13:42:10 neil Exp $
-** LL(1) Parser and code generator for Lua
-** See Copyright Notice in lua.h
-*/
-
-
-#include <stdio.h>
-#include <string.h>
-
-#include "lua.h"
-
-#include "lcode.h"
-#include "lfunc.h"
-#include "llex.h"
-#include "lmem.h"
-#include "lobject.h"
-#include "lopcodes.h"
-#include "lparser.h"
-#include "lstate.h"
-#include "lstring.h"
-
-#ifdef __MWERKS__
-/* To avoid name conflict resulting from the use of prefix header */
-#define stat lua_hack_stat
-#endif /* __MWERKS__ */
-
-
-/*
-** Constructors descriptor:
-** `n' indicates number of elements, and `k' signals whether
-** it is a list constructor (k = 0) or a record constructor (k = 1)
-** or empty (k = ';' or '}')
-*/
-typedef struct Constdesc {
- int n;
- int k;
-} Constdesc;
-
-
-typedef struct Breaklabel {
- struct Breaklabel *previous; /* chain */
- int breaklist;
- int stacklevel;
-} Breaklabel;
-
-
-
-
-/*
-** prototypes for recursive non-terminal functions
-*/
-static void body (LexState *ls, int needself, int line);
-static void chunk (LexState *ls);
-static void constructor (LexState *ls);
-static void expr (LexState *ls, expdesc *v);
-static void exp1 (LexState *ls);
-
-
-
-static void next (LexState *ls) {
- ls->lastline = ls->linenumber;
- if (ls->lookahead.token != TK_EOS) { /* is there a look-ahead token? */
- ls->t = ls->lookahead; /* use this one */
- ls->lookahead.token = TK_EOS; /* and discharge it */
- }
- else
- ls->t.token = luaX_lex(ls, &ls->t.seminfo); /* read next token */
-}
-
-
-static void lookahead (LexState *ls) {
- LUA_ASSERT(ls->lookahead.token == TK_EOS, "two look-aheads");
- ls->lookahead.token = luaX_lex(ls, &ls->lookahead.seminfo);
-}
-
-
-static void error_expected (LexState *ls, int token) {
- char buff[100], t[TOKEN_LEN];
- luaX_token2str(token, t);
- sprintf(buff, "`%.20s' expected", t);
- luaK_error(ls, buff);
-}
-
-
-static void check (LexState *ls, int c) {
- if (ls->t.token != c)
- error_expected(ls, c);
- next(ls);
-}
-
-
-static void check_condition (LexState *ls, int c, const char *msg) {
- if (!c) luaK_error(ls, msg);
-}
-
-
-static int optional (LexState *ls, int c) {
- if (ls->t.token == c) {
- next(ls);
- return 1;
- }
- else return 0;
-}
-
-
-static void check_match (LexState *ls, int what, int who, int where) {
- if (ls->t.token != what) {
- if (where == ls->linenumber)
- error_expected(ls, what);
- else {
- char buff[100];
- char t_what[TOKEN_LEN], t_who[TOKEN_LEN];
- luaX_token2str(what, t_what);
- luaX_token2str(who, t_who);
- sprintf(buff, "`%.20s' expected (to close `%.20s' at line %d)",
- t_what, t_who, where);
- luaK_error(ls, buff);
- }
- }
- next(ls);
-}
-
-
-static int string_constant (FuncState *fs, TString *s) {
- Proto *f = fs->f;
- int c = s->u.s.constindex;
- if (c >= f->nkstr || f->kstr[c] != s) {
- luaM_growvector(fs->L, f->kstr, f->nkstr, 1, TString *,
- "constant table overflow", MAXARG_U);
- c = f->nkstr++;
- f->kstr[c] = s;
- s->u.s.constindex = c; /* hint for next time */
- }
- return c;
-}
-
-
-static void code_string (LexState *ls, TString *s) {
- luaK_kstr(ls, string_constant(ls->fs, s));
-}
-
-
-static TString *str_checkname (LexState *ls) {
- TString *ts;
- check_condition(ls, (ls->t.token == TK_NAME), "<name> expected");
- ts = ls->t.seminfo.ts;
- next(ls);
- return ts;
-}
-
-
-static int checkname (LexState *ls) {
- return string_constant(ls->fs, str_checkname(ls));
-}
-
-
-static int luaI_registerlocalvar (LexState *ls, TString *varname) {
- Proto *f = ls->fs->f;
- luaM_growvector(ls->L, f->locvars, f->nlocvars, 1, LocVar, "", MAX_INT);
- f->locvars[f->nlocvars].varname = varname;
- return f->nlocvars++;
-}
-
-
-static void new_localvar (LexState *ls, TString *name, int n) {
- FuncState *fs = ls->fs;
- luaX_checklimit(ls, fs->nactloc+n+1, MAXLOCALS, "local variables");
- fs->actloc[fs->nactloc+n] = luaI_registerlocalvar(ls, name);
-}
-
-
-static void adjustlocalvars (LexState *ls, int nvars) {
- FuncState *fs = ls->fs;
- while (nvars--)
- fs->f->locvars[fs->actloc[fs->nactloc++]].startpc = fs->pc;
-}
-
-
-static void removelocalvars (LexState *ls, int nvars) {
- FuncState *fs = ls->fs;
- while (nvars--)
- fs->f->locvars[fs->actloc[--fs->nactloc]].endpc = fs->pc;
-}
-
-
-static void new_localvarstr (LexState *ls, const char *name, int n) {
- new_localvar(ls, luaS_newfixed(ls->L, name), n);
-}
-
-
-static int search_local (LexState *ls, TString *n, expdesc *var) {
- FuncState *fs;
- int level = 0;
- for (fs=ls->fs; fs; fs=fs->prev) {
- int i;
- for (i=fs->nactloc-1; i >= 0; i--) {
- if (n == fs->f->locvars[fs->actloc[i]].varname) {
- var->k = VLOCAL;
- var->u.index = i;
- return level;
- }
- }
- level++; /* `var' not found; check outer level */
- }
- var->k = VGLOBAL; /* not found in any level; must be global */
- return -1;
-}
-
-
-static void singlevar (LexState *ls, TString *n, expdesc *var) {
- int level = search_local(ls, n, var);
- if (level >= 1) /* neither local (0) nor global (-1)? */
- luaX_syntaxerror(ls, "cannot access a variable in outer scope", n->str);
- else if (level == -1) /* global? */
- var->u.index = string_constant(ls->fs, n);
-}
-
-
-static int indexupvalue (LexState *ls, expdesc *v) {
- FuncState *fs = ls->fs;
- int i;
- for (i=0; i<fs->nupvalues; i++) {
- if (fs->upvalues[i].k == v->k && fs->upvalues[i].u.index == v->u.index)
- return i;
- }
- /* new one */
- luaX_checklimit(ls, fs->nupvalues+1, MAXUPVALUES, "upvalues");
- fs->upvalues[fs->nupvalues] = *v;
- return fs->nupvalues++;
-}
-
-
-static void pushupvalue (LexState *ls, TString *n) {
- FuncState *fs = ls->fs;
- expdesc v;
- int level = search_local(ls, n, &v);
- if (level == -1) { /* global? */
- if (fs->prev == NULL)
- luaX_syntaxerror(ls, "cannot access upvalue in main", n->str);
- v.u.index = string_constant(fs->prev, n);
- }
- else if (level != 1)
- luaX_syntaxerror(ls,
- "upvalue must be global or local to immediately outer scope", n->str);
- luaK_code1(fs, OP_PUSHUPVALUE, indexupvalue(ls, &v));
-}
-
-
-static void adjust_mult_assign (LexState *ls, int nvars, int nexps) {
- FuncState *fs = ls->fs;
- int diff = nexps - nvars;
- if (nexps > 0 && luaK_lastisopen(fs)) { /* list ends in a function call */
- diff--; /* do not count function call itself */
- if (diff <= 0) { /* more variables than values? */
- luaK_setcallreturns(fs, -diff); /* function call provide extra values */
- diff = 0; /* no more difference */
- }
- else /* more values than variables */
- luaK_setcallreturns(fs, 0); /* call should provide no value */
- }
- /* push or pop eventual difference between list lengths */
- luaK_adjuststack(fs, diff);
-}
-
-
-static void code_params (LexState *ls, int nparams, int dots) {
- FuncState *fs = ls->fs;
- adjustlocalvars(ls, nparams);
- luaX_checklimit(ls, fs->nactloc, MAXPARAMS, "parameters");
- fs->f->numparams = fs->nactloc; /* `self' could be there already */
- fs->f->is_vararg = dots;
- if (dots) {
- new_localvarstr(ls, "arg", 0);
- adjustlocalvars(ls, 1);
- }
- luaK_deltastack(fs, fs->nactloc); /* count parameters in the stack */
-}
-
-
-static void enterbreak (FuncState *fs, Breaklabel *bl) {
- bl->stacklevel = fs->stacklevel;
- bl->breaklist = NO_JUMP;
- bl->previous = fs->bl;
- fs->bl = bl;
-}
-
-
-static void leavebreak (FuncState *fs, Breaklabel *bl) {
- fs->bl = bl->previous;
- LUA_ASSERT(bl->stacklevel == fs->stacklevel, "wrong levels");
- luaK_patchlist(fs, bl->breaklist, luaK_getlabel(fs));
-}
-
-
-static void pushclosure (LexState *ls, FuncState *func) {
- FuncState *fs = ls->fs;
- Proto *f = fs->f;
- int i;
- for (i=0; i<func->nupvalues; i++)
- luaK_tostack(ls, &func->upvalues[i], 1);
- luaM_growvector(ls->L, f->kproto, f->nkproto, 1, Proto *,
- "constant table overflow", MAXARG_A);
- f->kproto[f->nkproto++] = func->f;
- luaK_code2(fs, OP_CLOSURE, f->nkproto-1, func->nupvalues);
-}
-
-
-static void open_func (LexState *ls, FuncState *fs) {
- Proto *f = luaF_newproto(ls->L);
- fs->prev = ls->fs; /* linked list of funcstates */
- fs->ls = ls;
- fs->L = ls->L;
- ls->fs = fs;
- fs->stacklevel = 0;
- fs->nactloc = 0;
- fs->nupvalues = 0;
- fs->bl = NULL;
- fs->f = f;
- f->source = ls->source;
- fs->pc = 0;
- fs->lasttarget = 0;
- fs->lastline = 0;
- fs->jlt = NO_JUMP;
- f->code = NULL;
- f->maxstacksize = 0;
- f->numparams = 0; /* default for main chunk */
- f->is_vararg = 0; /* default for main chunk */
-}
-
-
-static void close_func (LexState *ls) {
- lua_State *L = ls->L;
- FuncState *fs = ls->fs;
- Proto *f = fs->f;
- luaK_code0(fs, OP_END);
- luaK_getlabel(fs); /* close eventual list of pending jumps */
- luaM_reallocvector(L, f->code, fs->pc, Instruction);
- luaM_reallocvector(L, f->kstr, f->nkstr, TString *);
- luaM_reallocvector(L, f->knum, f->nknum, Number);
- luaM_reallocvector(L, f->kproto, f->nkproto, Proto *);
- removelocalvars(ls, fs->nactloc);
- luaM_reallocvector(L, f->locvars, f->nlocvars, LocVar);
- luaM_reallocvector(L, f->lineinfo, f->nlineinfo+1, int);
- f->lineinfo[f->nlineinfo++] = MAX_INT; /* end flag */
- luaF_protook(L, f, fs->pc); /* proto is ok now */
- ls->fs = fs->prev;
- LUA_ASSERT(fs->bl == NULL, "wrong list end");
-}
-
-
-Proto *luaY_parser (lua_State *L, ZIO *z) {
- struct LexState lexstate;
- struct FuncState funcstate;
- luaX_setinput(L, &lexstate, z, luaS_new(L, zname(z)));
- open_func(&lexstate, &funcstate);
- next(&lexstate); /* read first token */
- chunk(&lexstate);
- check_condition(&lexstate, (lexstate.t.token == TK_EOS), "<eof> expected");
- close_func(&lexstate);
- LUA_ASSERT(funcstate.prev == NULL, "wrong list end");
- LUA_ASSERT(funcstate.nupvalues == 0, "no upvalues in main");
- return funcstate.f;
-}
-
-
-
-/*============================================================*/
-/* GRAMMAR RULES */
-/*============================================================*/
-
-
-static int explist1 (LexState *ls) {
- /* explist1 -> expr { ',' expr } */
- int n = 1; /* at least one expression */
- expdesc v;
- expr(ls, &v);
- while (ls->t.token == ',') {
- luaK_tostack(ls, &v, 1); /* gets only 1 value from previous expression */
- next(ls); /* skip comma */
- expr(ls, &v);
- n++;
- }
- luaK_tostack(ls, &v, 0); /* keep open number of values of last expression */
- return n;
-}
-
-
-static void funcargs (LexState *ls, int slf) {
- FuncState *fs = ls->fs;
- int slevel = fs->stacklevel - slf - 1; /* where is func in the stack */
- switch (ls->t.token) {
- case '(': { /* funcargs -> '(' [ explist1 ] ')' */
- int line = ls->linenumber;
- int nargs = 0;
- next(ls);
- if (ls->t.token != ')') /* arg list not empty? */
- nargs = explist1(ls);
- check_match(ls, ')', '(', line);
-#ifdef LUA_COMPAT_ARGRET
- if (nargs > 0) /* arg list is not empty? */
- luaK_setcallreturns(fs, 1); /* last call returns only 1 value */
-#else
- UNUSED(nargs); /* to avoid warnings */
-#endif
- break;
- }
- case '{': { /* funcargs -> constructor */
- constructor(ls);
- break;
- }
- case TK_STRING: { /* funcargs -> STRING */
- code_string(ls, ls->t.seminfo.ts); /* must use `seminfo' before `next' */
- next(ls);
- break;
- }
- default: {
- luaK_error(ls, "function arguments expected");
- break;
- }
- }
- fs->stacklevel = slevel; /* call will remove function and arguments */
- luaK_code2(fs, OP_CALL, slevel, MULT_RET);
-}
-
-
-static void var_or_func_tail (LexState *ls, expdesc *v) {
- for (;;) {
- switch (ls->t.token) {
- case '.': { /* var_or_func_tail -> '.' NAME */
- next(ls);
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- luaK_kstr(ls, checkname(ls));
- v->k = VINDEXED;
- break;
- }
- case '[': { /* var_or_func_tail -> '[' exp1 ']' */
- next(ls);
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- v->k = VINDEXED;
- exp1(ls);
- check(ls, ']');
- break;
- }
- case ':': { /* var_or_func_tail -> ':' NAME funcargs */
- int name;
- next(ls);
- name = checkname(ls);
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- luaK_code1(ls->fs, OP_PUSHSELF, name);
- funcargs(ls, 1);
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
- break;
- }
- case '(': case TK_STRING: case '{': { /* var_or_func_tail -> funcargs */
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- funcargs(ls, 0);
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
- break;
- }
- default: return; /* should be follow... */
- }
- }
-}
-
-
-static void var_or_func (LexState *ls, expdesc *v) {
- /* var_or_func -> ['%'] NAME var_or_func_tail */
- if (optional(ls, '%')) { /* upvalue? */
- pushupvalue(ls, str_checkname(ls));
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
- }
- else /* variable name */
- singlevar(ls, str_checkname(ls), v);
- var_or_func_tail(ls, v);
-}
-
-
-
-/*
-** {======================================================================
-** Rules for Constructors
-** =======================================================================
-*/
-
-
-static void recfield (LexState *ls) {
- /* recfield -> (NAME | '['exp1']') = exp1 */
- switch (ls->t.token) {
- case TK_NAME: {
- luaK_kstr(ls, checkname(ls));
- break;
- }
- case '[': {
- next(ls);
- exp1(ls);
- check(ls, ']');
- break;
- }
- default: luaK_error(ls, "<name> or `[' expected");
- }
- check(ls, '=');
- exp1(ls);
-}
-
-
-static int recfields (LexState *ls) {
- /* recfields -> recfield { ',' recfield } [','] */
- FuncState *fs = ls->fs;
- int n = 1; /* at least one element */
- recfield(ls);
- while (ls->t.token == ',') {
- next(ls);
- if (ls->t.token == ';' || ls->t.token == '}')
- break;
- recfield(ls);
- n++;
- if (n%RFIELDS_PER_FLUSH == 0)
- luaK_code1(fs, OP_SETMAP, RFIELDS_PER_FLUSH);
- }
- luaK_code1(fs, OP_SETMAP, n%RFIELDS_PER_FLUSH);
- return n;
-}
-
-
-static int listfields (LexState *ls) {
- /* listfields -> exp1 { ',' exp1 } [','] */
- FuncState *fs = ls->fs;
- int n = 1; /* at least one element */
- exp1(ls);
- while (ls->t.token == ',') {
- next(ls);
- if (ls->t.token == ';' || ls->t.token == '}')
- break;
- exp1(ls);
- n++;
- luaX_checklimit(ls, n/LFIELDS_PER_FLUSH, MAXARG_A,
- "`item groups' in a list initializer");
- if (n%LFIELDS_PER_FLUSH == 0)
- luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH - 1, LFIELDS_PER_FLUSH);
- }
- luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH, n%LFIELDS_PER_FLUSH);
- return n;
-}
-
-
-
-static void constructor_part (LexState *ls, Constdesc *cd) {
- switch (ls->t.token) {
- case ';': case '}': { /* constructor_part -> empty */
- cd->n = 0;
- cd->k = ls->t.token;
- break;
- }
- case TK_NAME: { /* may be listfields or recfields */
- lookahead(ls);
- if (ls->lookahead.token != '=') /* expression? */
- goto case_default;
- /* else go through to recfields */
- }
- case '[': { /* constructor_part -> recfields */
- cd->n = recfields(ls);
- cd->k = 1; /* record */
- break;
- }
- default: { /* constructor_part -> listfields */
- case_default:
- cd->n = listfields(ls);
- cd->k = 0; /* list */
- break;
- }
- }
-}
-
-
-static void constructor (LexState *ls) {
- /* constructor -> '{' constructor_part [';' constructor_part] '}' */
- FuncState *fs = ls->fs;
- int line = ls->linenumber;
- int pc = luaK_code1(fs, OP_CREATETABLE, 0);
- int nelems;
- Constdesc cd;
- check(ls, '{');
- constructor_part(ls, &cd);
- nelems = cd.n;
- if (optional(ls, ';')) {
- Constdesc other_cd;
- constructor_part(ls, &other_cd);
- check_condition(ls, (cd.k != other_cd.k), "invalid constructor syntax");
- nelems += other_cd.n;
- }
- check_match(ls, '}', '{', line);
- luaX_checklimit(ls, nelems, MAXARG_U, "elements in a table constructor");
- SETARG_U(fs->f->code[pc], nelems); /* set initial table size */
-}
-
-/* }====================================================================== */
-
-
-
-
-/*
-** {======================================================================
-** Expression parsing
-** =======================================================================
-*/
-
-
-static void simpleexp (LexState *ls, expdesc *v) {
- FuncState *fs = ls->fs;
- switch (ls->t.token) {
- case TK_NUMBER: { /* simpleexp -> NUMBER */
- Number r = ls->t.seminfo.r;
- next(ls);
- luaK_number(fs, r);
- break;
- }
- case TK_STRING: { /* simpleexp -> STRING */
- code_string(ls, ls->t.seminfo.ts); /* must use `seminfo' before `next' */
- next(ls);
- break;
- }
- case TK_NIL: { /* simpleexp -> NIL */
- luaK_adjuststack(fs, -1);
- next(ls);
- break;
- }
- case '{': { /* simpleexp -> constructor */
- constructor(ls);
- break;
- }
- case TK_FUNCTION: { /* simpleexp -> FUNCTION body */
- next(ls);
- body(ls, 0, ls->linenumber);
- break;
- }
- case '(': { /* simpleexp -> '(' expr ')' */
- next(ls);
- expr(ls, v);
- check(ls, ')');
- return;
- }
- case TK_NAME: case '%': {
- var_or_func(ls, v);
- return;
- }
- default: {
- luaK_error(ls, "<expression> expected");
- return;
- }
- }
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
-}
-
-
-static void exp1 (LexState *ls) {
- expdesc v;
- expr(ls, &v);
- luaK_tostack(ls, &v, 1);
-}
-
-
-static UnOpr getunopr (int op) {
- switch (op) {
- case TK_NOT: return OPR_NOT;
- case '-': return OPR_MINUS;
- default: return OPR_NOUNOPR;
- }
-}
-
-
-static BinOpr getbinopr (int op) {
- switch (op) {
- case '+': return OPR_ADD;
- case '-': return OPR_SUB;
- case '*': return OPR_MULT;
- case '/': return OPR_DIV;
- case '^': return OPR_POW;
- case TK_CONCAT: return OPR_CONCAT;
- case TK_NE: return OPR_NE;
- case TK_EQ: return OPR_EQ;
- case '<': return OPR_LT;
- case TK_LE: return OPR_LE;
- case '>': return OPR_GT;
- case TK_GE: return OPR_GE;
- case TK_AND: return OPR_AND;
- case TK_OR: return OPR_OR;
- default: return OPR_NOBINOPR;
- }
-}
-
-
-static const struct {
- char left; /* left priority for each binary operator */
- char right; /* right priority */
-} priority[] = { /* ORDER OPR */
- {5, 5}, {5, 5}, {6, 6}, {6, 6}, /* arithmetic */
- {9, 8}, {4, 3}, /* power and concat (right associative) */
- {2, 2}, {2, 2}, /* equality */
- {2, 2}, {2, 2}, {2, 2}, {2, 2}, /* order */
- {1, 1}, {1, 1} /* logical */
-};
-
-#define UNARY_PRIORITY 7 /* priority for unary operators */
-
-
-/*
-** subexpr -> (simplexep | unop subexpr) { binop subexpr }
-** where `binop' is any binary operator with a priority higher than `limit'
-*/
-static BinOpr subexpr (LexState *ls, expdesc *v, int limit) {
- BinOpr op;
- UnOpr uop = getunopr(ls->t.token);
- if (uop != OPR_NOUNOPR) {
- next(ls);
- subexpr(ls, v, UNARY_PRIORITY);
- luaK_prefix(ls, uop, v);
- }
- else simpleexp(ls, v);
- /* expand while operators have priorities higher than `limit' */
- op = getbinopr(ls->t.token);
- while (op != OPR_NOBINOPR && priority[op].left > limit) {
- expdesc v2;
- BinOpr nextop;
- next(ls);
- luaK_infix(ls, op, v);
- /* read sub-expression with higher priority */
- nextop = subexpr(ls, &v2, priority[op].right);
- luaK_posfix(ls, op, v, &v2);
- op = nextop;
- }
- return op; /* return first untreated operator */
-}
-
-
-static void expr (LexState *ls, expdesc *v) {
- subexpr(ls, v, -1);
-}
-
-/* }==================================================================== */
-
-
-/*
-** {======================================================================
-** Rules for Statements
-** =======================================================================
-*/
-
-
-static int block_follow (int token) {
- switch (token) {
- case TK_ELSE: case TK_ELSEIF: case TK_END:
- case TK_UNTIL: case TK_EOS:
- return 1;
- default: return 0;
- }
-}
-
-
-static void block (LexState *ls) {
- /* block -> chunk */
- FuncState *fs = ls->fs;
- int nactloc = fs->nactloc;
- chunk(ls);
- luaK_adjuststack(fs, fs->nactloc - nactloc); /* remove local variables */
- removelocalvars(ls, fs->nactloc - nactloc);
-}
-
-
-static int assignment (LexState *ls, expdesc *v, int nvars) {
- int left = 0; /* number of values left in the stack after assignment */
- luaX_checklimit(ls, nvars, MAXVARSLH, "variables in a multiple assignment");
- if (ls->t.token == ',') { /* assignment -> ',' NAME assignment */
- expdesc nv;
- next(ls);
- var_or_func(ls, &nv);
- check_condition(ls, (nv.k != VEXP), "syntax error");
- left = assignment(ls, &nv, nvars+1);
- }
- else { /* assignment -> '=' explist1 */
- int nexps;
- check(ls, '=');
- nexps = explist1(ls);
- adjust_mult_assign(ls, nvars, nexps);
- }
- if (v->k != VINDEXED)
- luaK_storevar(ls, v);
- else { /* there may be garbage between table-index and value */
- luaK_code2(ls->fs, OP_SETTABLE, left+nvars+2, 1);
- left += 2;
- }
- return left;
-}
-
-
-static void cond (LexState *ls, expdesc *v) {
- /* cond -> exp */
- expr(ls, v); /* read condition */
- luaK_goiftrue(ls->fs, v, 0);
-}
-
-
-static void whilestat (LexState *ls, int line) {
- /* whilestat -> WHILE cond DO block END */
- FuncState *fs = ls->fs;
- int while_init = luaK_getlabel(fs);
- expdesc v;
- Breaklabel bl;
- enterbreak(fs, &bl);
- next(ls);
- cond(ls, &v);
- check(ls, TK_DO);
- block(ls);
- luaK_patchlist(fs, luaK_jump(fs), while_init);
- luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
- check_match(ls, TK_END, TK_WHILE, line);
- leavebreak(fs, &bl);
-}
-
-
-static void repeatstat (LexState *ls, int line) {
- /* repeatstat -> REPEAT block UNTIL cond */
- FuncState *fs = ls->fs;
- int repeat_init = luaK_getlabel(fs);
- expdesc v;
- Breaklabel bl;
- enterbreak(fs, &bl);
- next(ls);
- block(ls);
- check_match(ls, TK_UNTIL, TK_REPEAT, line);
- cond(ls, &v);
- luaK_patchlist(fs, v.u.l.f, repeat_init);
- leavebreak(fs, &bl);
-}
-
-
-static void forbody (LexState *ls, int nvar, OpCode prepfor, OpCode loopfor) {
- /* forbody -> DO block END */
- FuncState *fs = ls->fs;
- int prep = luaK_code1(fs, prepfor, NO_JUMP);
- int blockinit = luaK_getlabel(fs);
- check(ls, TK_DO);
- adjustlocalvars(ls, nvar); /* scope for control variables */
- block(ls);
- luaK_patchlist(fs, luaK_code1(fs, loopfor, NO_JUMP), blockinit);
- luaK_patchlist(fs, prep, luaK_getlabel(fs));
- removelocalvars(ls, nvar);
-}
-
-
-static void fornum (LexState *ls, TString *varname) {
- /* fornum -> NAME = exp1,exp1[,exp1] forbody */
- FuncState *fs = ls->fs;
- check(ls, '=');
- exp1(ls); /* initial value */
- check(ls, ',');
- exp1(ls); /* limit */
- if (optional(ls, ','))
- exp1(ls); /* optional step */
- else
- luaK_code1(fs, OP_PUSHINT, 1); /* default step */
- new_localvar(ls, varname, 0);
- new_localvarstr(ls, "(limit)", 1);
- new_localvarstr(ls, "(step)", 2);
- forbody(ls, 3, OP_FORPREP, OP_FORLOOP);
-}
-
-
-static void forlist (LexState *ls, TString *indexname) {
- /* forlist -> NAME,NAME IN exp1 forbody */
- TString *valname;
- check(ls, ',');
- valname = str_checkname(ls);
- /* next test is dirty, but avoids `in' being a reserved word */
- check_condition(ls,
- (ls->t.token == TK_NAME && ls->t.seminfo.ts == luaS_new(ls->L, "in")),
- "`in' expected");
- next(ls); /* skip `in' */
- exp1(ls); /* table */
- new_localvarstr(ls, "(table)", 0);
- new_localvar(ls, indexname, 1);
- new_localvar(ls, valname, 2);
- forbody(ls, 3, OP_LFORPREP, OP_LFORLOOP);
-}
-
-
-static void forstat (LexState *ls, int line) {
- /* forstat -> fornum | forlist */
- FuncState *fs = ls->fs;
- TString *varname;
- Breaklabel bl;
- enterbreak(fs, &bl);
- next(ls); /* skip `for' */
- varname = str_checkname(ls); /* first variable name */
- switch (ls->t.token) {
- case '=': fornum(ls, varname); break;
- case ',': forlist(ls, varname); break;
- default: luaK_error(ls, "`=' or `,' expected");
- }
- check_match(ls, TK_END, TK_FOR, line);
- leavebreak(fs, &bl);
-}
-
-
-static void test_then_block (LexState *ls, expdesc *v) {
- /* test_then_block -> [IF | ELSEIF] cond THEN block */
- next(ls); /* skip IF or ELSEIF */
- cond(ls, v);
- check(ls, TK_THEN);
- block(ls); /* `then' part */
-}
-
-
-static void ifstat (LexState *ls, int line) {
- /* ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END */
- FuncState *fs = ls->fs;
- expdesc v;
- int escapelist = NO_JUMP;
- test_then_block(ls, &v); /* IF cond THEN block */
- while (ls->t.token == TK_ELSEIF) {
- luaK_concat(fs, &escapelist, luaK_jump(fs));
- luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
- test_then_block(ls, &v); /* ELSEIF cond THEN block */
- }
- if (ls->t.token == TK_ELSE) {
- luaK_concat(fs, &escapelist, luaK_jump(fs));
- luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
- next(ls); /* skip ELSE */
- block(ls); /* `else' part */
- }
- else
- luaK_concat(fs, &escapelist, v.u.l.f);
- luaK_patchlist(fs, escapelist, luaK_getlabel(fs));
- check_match(ls, TK_END, TK_IF, line);
-}
-
-
-static void localstat (LexState *ls) {
- /* stat -> LOCAL NAME {',' NAME} ['=' explist1] */
- int nvars = 0;
- int nexps;
- do {
- next(ls); /* skip LOCAL or ',' */
- new_localvar(ls, str_checkname(ls), nvars++);
- } while (ls->t.token == ',');
- if (optional(ls, '='))
- nexps = explist1(ls);
- else
- nexps = 0;
- adjust_mult_assign(ls, nvars, nexps);
- adjustlocalvars(ls, nvars);
-}
-
-
-static int funcname (LexState *ls, expdesc *v) {
- /* funcname -> NAME [':' NAME | '.' NAME] */
- int needself = 0;
- singlevar(ls, str_checkname(ls), v);
- if (ls->t.token == ':' || ls->t.token == '.') {
- needself = (ls->t.token == ':');
- next(ls);
- luaK_tostack(ls, v, 1);
- luaK_kstr(ls, checkname(ls));
- v->k = VINDEXED;
- }
- return needself;
-}
-
-
-static void funcstat (LexState *ls, int line) {
- /* funcstat -> FUNCTION funcname body */
- int needself;
- expdesc v;
- next(ls); /* skip FUNCTION */
- needself = funcname(ls, &v);
- body(ls, needself, line);
- luaK_storevar(ls, &v);
-}
-
-
-static void namestat (LexState *ls) {
- /* stat -> func | ['%'] NAME assignment */
- FuncState *fs = ls->fs;
- expdesc v;
- var_or_func(ls, &v);
- if (v.k == VEXP) { /* stat -> func */
- check_condition(ls, luaK_lastisopen(fs), "syntax error"); /* an upvalue? */
- luaK_setcallreturns(fs, 0); /* call statement uses no results */
- }
- else { /* stat -> ['%'] NAME assignment */
- int left = assignment(ls, &v, 1);
- luaK_adjuststack(fs, left); /* remove eventual garbage left on stack */
- }
-}
-
-
-static void retstat (LexState *ls) {
- /* stat -> RETURN explist */
- FuncState *fs = ls->fs;
- next(ls); /* skip RETURN */
- if (!block_follow(ls->t.token))
- explist1(ls); /* optional return values */
- luaK_code1(fs, OP_RETURN, ls->fs->nactloc);
- fs->stacklevel = fs->nactloc; /* removes all temp values */
-}
-
-
-static void breakstat (LexState *ls) {
- /* stat -> BREAK [NAME] */
- FuncState *fs = ls->fs;
- int currentlevel = fs->stacklevel;
- Breaklabel *bl = fs->bl;
- if (!bl)
- luaK_error(ls, "no loop to break");
- next(ls); /* skip BREAK */
- luaK_adjuststack(fs, currentlevel - bl->stacklevel);
- luaK_concat(fs, &bl->breaklist, luaK_jump(fs));
- /* correct stack for compiler and symbolic execution */
- luaK_adjuststack(fs, bl->stacklevel - currentlevel);
-}
-
-
-static int stat (LexState *ls) {
- int line = ls->linenumber; /* may be needed for error messages */
- switch (ls->t.token) {
- case TK_IF: { /* stat -> ifstat */
- ifstat(ls, line);
- return 0;
- }
- case TK_WHILE: { /* stat -> whilestat */
- whilestat(ls, line);
- return 0;
- }
- case TK_DO: { /* stat -> DO block END */
- next(ls); /* skip DO */
- block(ls);
- check_match(ls, TK_END, TK_DO, line);
- return 0;
- }
- case TK_FOR: { /* stat -> forstat */
- forstat(ls, line);
- return 0;
- }
- case TK_REPEAT: { /* stat -> repeatstat */
- repeatstat(ls, line);
- return 0;
- }
- case TK_FUNCTION: { /* stat -> funcstat */
- funcstat(ls, line);
- return 0;
- }
- case TK_LOCAL: { /* stat -> localstat */
- localstat(ls);
- return 0;
- }
- case TK_NAME: case '%': { /* stat -> namestat */
- namestat(ls);
- return 0;
- }
- case TK_RETURN: { /* stat -> retstat */
- retstat(ls);
- return 1; /* must be last statement */
- }
- case TK_BREAK: { /* stat -> breakstat */
- breakstat(ls);
- return 1; /* must be last statement */
- }
- default: {
- luaK_error(ls, "<statement> expected");
- return 0; /* to avoid warnings */
- }
- }
-}
-
-
-static void parlist (LexState *ls) {
- /* parlist -> [ param { ',' param } ] */
- int nparams = 0;
- int dots = 0;
- if (ls->t.token != ')') { /* is `parlist' not empty? */
- do {
- switch (ls->t.token) {
- case TK_DOTS: next(ls); dots = 1; break;
- case TK_NAME: new_localvar(ls, str_checkname(ls), nparams++); break;
- default: luaK_error(ls, "<name> or `...' expected");
- }
- } while (!dots && optional(ls, ','));
- }
- code_params(ls, nparams, dots);
-}
-
-
-static void body (LexState *ls, int needself, int line) {
- /* body -> '(' parlist ')' chunk END */
- FuncState new_fs;
- open_func(ls, &new_fs);
- new_fs.f->lineDefined = line;
- check(ls, '(');
- if (needself) {
- new_localvarstr(ls, "self", 0);
- adjustlocalvars(ls, 1);
- }
- parlist(ls);
- check(ls, ')');
- chunk(ls);
- check_match(ls, TK_END, TK_FUNCTION, line);
- close_func(ls);
- pushclosure(ls, &new_fs);
-}
-
-
-/* }====================================================================== */
-
-
-static void chunk (LexState *ls) {
- /* chunk -> { stat [';'] } */
- int islast = 0;
- while (!islast && !block_follow(ls->t.token)) {
- islast = stat(ls);
- optional(ls, ';');
- LUA_ASSERT(ls->fs->stacklevel == ls->fs->nactloc,
- "stack size != # local vars");
- }
-}
-