mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 11:37:35 +00:00
896 lines
29 KiB
C
896 lines
29 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
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╚──────────────────────────────────────────────────────────────────────────────╝
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│ │
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│ Lua │
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│ Copyright © 2004-2021 Lua.org, PUC-Rio. │
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│ │
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│ Permission is hereby granted, free of charge, to any person obtaining │
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│ a copy of this software and associated documentation files (the │
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│ "Software"), to deal in the Software without restriction, including │
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│ without limitation the rights to use, copy, modify, merge, publish, │
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│ distribute, sublicense, and/or sell copies of the Software, and to │
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│ permit persons to whom the Software is furnished to do so, subject to │
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│ the following conditions: │
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│ │
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│ The above copyright notice and this permission notice shall be │
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│ included in all copies or substantial portions of the Software. │
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│ │
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│ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, │
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│ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF │
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│ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. │
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│ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY │
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│ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, │
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│ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE │
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│ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. │
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│ │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#define ldebug_c
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#define LUA_CORE
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#include "libc/str/str.h"
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#include "third_party/lua/lapi.h"
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#include "third_party/lua/lcode.h"
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#include "third_party/lua/ldebug.h"
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#include "third_party/lua/ldo.h"
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#include "third_party/lua/lfunc.h"
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#include "third_party/lua/lobject.h"
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#include "third_party/lua/lopcodes.h"
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#include "third_party/lua/lprefix.h"
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#include "third_party/lua/lstate.h"
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#include "third_party/lua/lstring.h"
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#include "third_party/lua/ltable.h"
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#include "third_party/lua/ltm.h"
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#include "third_party/lua/lua.h"
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#include "third_party/lua/lvm.h"
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// clang-format off
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asm(".ident\t\"\\n\\n\
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Lua 5.4.3 (MIT License)\\n\
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Copyright 1994–2021 Lua.org, PUC-Rio.\"");
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asm(".include \"libc/disclaimer.inc\"");
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#define noLuaClosure(f) ((f) == NULL || (f)->c.tt == LUA_VCCL)
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static const char *funcnamefromcode (lua_State *L, CallInfo *ci,
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const char **name);
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static int currentpc (CallInfo *ci) {
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lua_assert(isLua(ci));
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return pcRel(ci->u.l.savedpc, ci_func(ci)->p);
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}
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/*
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** Get a "base line" to find the line corresponding to an instruction.
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** Base lines are regularly placed at MAXIWTHABS intervals, so usually
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** an integer division gets the right place. When the source file has
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** large sequences of empty/comment lines, it may need extra entries,
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** so the original estimate needs a correction.
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** If the original estimate is -1, the initial 'if' ensures that the
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** 'while' will run at least once.
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** The assertion that the estimate is a lower bound for the correct base
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** is valid as long as the debug info has been generated with the same
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** value for MAXIWTHABS or smaller. (Previous releases use a little
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** smaller value.)
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*/
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static int getbaseline (const Proto *f, int pc, int *basepc) {
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if (f->sizeabslineinfo == 0 || pc < f->abslineinfo[0].pc) {
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*basepc = -1; /* start from the beginning */
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return f->linedefined;
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}
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else {
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int i = cast_uint(pc) / MAXIWTHABS - 1; /* get an estimate */
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/* estimate must be a lower bond of the correct base */
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lua_assert(i < 0 ||
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(i < f->sizeabslineinfo && f->abslineinfo[i].pc <= pc));
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while (i + 1 < f->sizeabslineinfo && pc >= f->abslineinfo[i + 1].pc)
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i++; /* low estimate; adjust it */
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*basepc = f->abslineinfo[i].pc;
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return f->abslineinfo[i].line;
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}
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}
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/*
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** Get the line corresponding to instruction 'pc' in function 'f';
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** first gets a base line and from there does the increments until
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** the desired instruction.
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*/
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int luaG_getfuncline (const Proto *f, int pc) {
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if (f->lineinfo == NULL) /* no debug information? */
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return -1;
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else {
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int basepc;
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int baseline = getbaseline(f, pc, &basepc);
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while (basepc++ < pc) { /* walk until given instruction */
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lua_assert(f->lineinfo[basepc] != ABSLINEINFO);
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baseline += f->lineinfo[basepc]; /* correct line */
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}
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return baseline;
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}
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}
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static int getcurrentline (CallInfo *ci) {
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return luaG_getfuncline(ci_func(ci)->p, currentpc(ci));
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}
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/*
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** Set 'trap' for all active Lua frames.
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** This function can be called during a signal, under "reasonable"
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** assumptions. A new 'ci' is completely linked in the list before it
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** becomes part of the "active" list, and we assume that pointers are
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** atomic; see comment in next function.
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** (A compiler doing interprocedural optimizations could, theoretically,
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** reorder memory writes in such a way that the list could be
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** temporarily broken while inserting a new element. We simply assume it
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** has no good reasons to do that.)
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*/
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static void settraps (CallInfo *ci) {
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for (; ci != NULL; ci = ci->previous)
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if (isLua(ci))
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ci->u.l.trap = 1;
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}
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/*
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** This function can be called during a signal, under "reasonable"
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** assumptions.
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** Fields 'basehookcount' and 'hookcount' (set by 'resethookcount')
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** are for debug only, and it is no problem if they get arbitrary
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** values (causes at most one wrong hook call). 'hookmask' is an atomic
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** value. We assume that pointers are atomic too (e.g., gcc ensures that
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** for all platforms where it runs). Moreover, 'hook' is always checked
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** before being called (see 'luaD_hook').
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*/
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LUA_API void lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
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if (func == NULL || mask == 0) { /* turn off hooks? */
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mask = 0;
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func = NULL;
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}
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L->hook = func;
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L->basehookcount = count;
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resethookcount(L);
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L->hookmask = cast_byte(mask);
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if (mask)
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settraps(L->ci); /* to trace inside 'luaV_execute' */
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}
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LUA_API lua_Hook lua_gethook (lua_State *L) {
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return L->hook;
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}
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LUA_API int lua_gethookmask (lua_State *L) {
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return L->hookmask;
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}
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LUA_API int lua_gethookcount (lua_State *L) {
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return L->basehookcount;
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}
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LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
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int status;
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CallInfo *ci;
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if (level < 0) return 0; /* invalid (negative) level */
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lua_lock(L);
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for (ci = L->ci; level > 0 && ci != &L->base_ci; ci = ci->previous)
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level--;
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if (level == 0 && ci != &L->base_ci) { /* level found? */
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status = 1;
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ar->i_ci = ci;
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}
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else status = 0; /* no such level */
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lua_unlock(L);
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return status;
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}
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static const char *upvalname (const Proto *p, int uv) {
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TString *s = check_exp(uv < p->sizeupvalues, p->upvalues[uv].name);
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if (s == NULL) return "?";
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else return getstr(s);
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}
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static const char *findvararg (CallInfo *ci, int n, StkId *pos) {
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if (clLvalue(s2v(ci->func))->p->is_vararg) {
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int nextra = ci->u.l.nextraargs;
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if (n >= -nextra) { /* 'n' is negative */
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*pos = ci->func - nextra - (n + 1);
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return "(vararg)"; /* generic name for any vararg */
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}
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}
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return NULL; /* no such vararg */
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}
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const char *luaG_findlocal (lua_State *L, CallInfo *ci, int n, StkId *pos) {
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StkId base = ci->func + 1;
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const char *name = NULL;
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if (isLua(ci)) {
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if (n < 0) /* access to vararg values? */
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return findvararg(ci, n, pos);
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else
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name = luaF_getlocalname(ci_func(ci)->p, n, currentpc(ci));
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}
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if (name == NULL) { /* no 'standard' name? */
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StkId limit = (ci == L->ci) ? L->top : ci->next->func;
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if (limit - base >= n && n > 0) { /* is 'n' inside 'ci' stack? */
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/* generic name for any valid slot */
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name = isLua(ci) ? "(temporary)" : "(C temporary)";
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}
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else
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return NULL; /* no name */
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}
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if (pos)
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*pos = base + (n - 1);
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return name;
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}
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LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
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const char *name;
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lua_lock(L);
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if (ar == NULL) { /* information about non-active function? */
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if (!isLfunction(s2v(L->top - 1))) /* not a Lua function? */
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name = NULL;
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else /* consider live variables at function start (parameters) */
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name = luaF_getlocalname(clLvalue(s2v(L->top - 1))->p, n, 0);
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}
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else { /* active function; get information through 'ar' */
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StkId pos = NULL; /* to avoid warnings */
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name = luaG_findlocal(L, ar->i_ci, n, &pos);
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if (name) {
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setobjs2s(L, L->top, pos);
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api_incr_top(L);
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}
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}
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lua_unlock(L);
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return name;
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}
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LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
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StkId pos = NULL; /* to avoid warnings */
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const char *name;
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lua_lock(L);
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name = luaG_findlocal(L, ar->i_ci, n, &pos);
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if (name) {
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setobjs2s(L, pos, L->top - 1);
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L->top--; /* pop value */
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}
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lua_unlock(L);
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return name;
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}
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static void funcinfo (lua_Debug *ar, Closure *cl) {
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if (noLuaClosure(cl)) {
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ar->source = "=[C]";
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ar->srclen = LL("=[C]");
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ar->linedefined = -1;
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ar->lastlinedefined = -1;
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ar->what = "C";
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}
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else {
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const Proto *p = cl->l.p;
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if (p->source) {
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ar->source = getstr(p->source);
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ar->srclen = tsslen(p->source);
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}
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else {
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ar->source = "=?";
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ar->srclen = LL("=?");
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}
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ar->linedefined = p->linedefined;
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ar->lastlinedefined = p->lastlinedefined;
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ar->what = (ar->linedefined == 0) ? "main" : "Lua";
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}
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luaO_chunkid(ar->short_src, ar->source, ar->srclen);
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}
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static int nextline (const Proto *p, int currentline, int pc) {
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if (p->lineinfo[pc] != ABSLINEINFO)
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return currentline + p->lineinfo[pc];
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else
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return luaG_getfuncline(p, pc);
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}
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static void collectvalidlines (lua_State *L, Closure *f) {
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if (noLuaClosure(f)) {
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setnilvalue(s2v(L->top));
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api_incr_top(L);
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}
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else {
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int i;
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TValue v;
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const Proto *p = f->l.p;
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int currentline = p->linedefined;
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Table *t = luaH_new(L); /* new table to store active lines */
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sethvalue2s(L, L->top, t); /* push it on stack */
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api_incr_top(L);
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setbtvalue(&v); /* boolean 'true' to be the value of all indices */
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for (i = 0; i < p->sizelineinfo; i++) { /* for all instructions */
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currentline = nextline(p, currentline, i); /* get its line */
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luaH_setint(L, t, currentline, &v); /* table[line] = true */
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}
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}
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}
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static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
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if (ci == NULL) /* no 'ci'? */
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return NULL; /* no info */
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else if (ci->callstatus & CIST_FIN) { /* is this a finalizer? */
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*name = "__gc";
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return "metamethod"; /* report it as such */
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}
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/* calling function is a known Lua function? */
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else if (!(ci->callstatus & CIST_TAIL) && isLua(ci->previous))
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return funcnamefromcode(L, ci->previous, name);
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else return NULL; /* no way to find a name */
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}
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static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
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Closure *f, CallInfo *ci) {
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int status = 1;
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for (; *what; what++) {
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switch (*what) {
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case 'S': {
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funcinfo(ar, f);
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break;
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}
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case 'l': {
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ar->currentline = (ci && isLua(ci)) ? getcurrentline(ci) : -1;
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break;
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}
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case 'u': {
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ar->nups = (f == NULL) ? 0 : f->c.nupvalues;
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if (noLuaClosure(f)) {
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ar->isvararg = 1;
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ar->nparams = 0;
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}
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else {
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ar->isvararg = f->l.p->is_vararg;
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ar->nparams = f->l.p->numparams;
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}
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break;
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}
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case 't': {
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ar->istailcall = (ci) ? ci->callstatus & CIST_TAIL : 0;
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break;
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}
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case 'n': {
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ar->namewhat = getfuncname(L, ci, &ar->name);
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if (ar->namewhat == NULL) {
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ar->namewhat = ""; /* not found */
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ar->name = NULL;
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}
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break;
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}
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case 'r': {
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if (ci == NULL || !(ci->callstatus & CIST_TRAN))
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ar->ftransfer = ar->ntransfer = 0;
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else {
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ar->ftransfer = ci->u2.transferinfo.ftransfer;
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ar->ntransfer = ci->u2.transferinfo.ntransfer;
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}
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break;
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}
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case 'L':
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case 'f': /* handled by lua_getinfo */
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break;
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default: status = 0; /* invalid option */
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}
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}
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return status;
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}
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LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
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int status;
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Closure *cl;
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CallInfo *ci;
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TValue *func;
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lua_lock(L);
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if (*what == '>') {
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ci = NULL;
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func = s2v(L->top - 1);
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api_check(L, ttisfunction(func), "function expected");
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what++; /* skip the '>' */
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L->top--; /* pop function */
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}
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else {
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ci = ar->i_ci;
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func = s2v(ci->func);
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lua_assert(ttisfunction(func));
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}
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cl = ttisclosure(func) ? clvalue(func) : NULL;
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status = auxgetinfo(L, what, ar, cl, ci);
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if (strchr(what, 'f')) {
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setobj2s(L, L->top, func);
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api_incr_top(L);
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}
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if (strchr(what, 'L'))
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collectvalidlines(L, cl);
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lua_unlock(L);
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return status;
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}
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/*
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** {======================================================
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** Symbolic Execution
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** =======================================================
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*/
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static const char *getobjname (const Proto *p, int lastpc, int reg,
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const char **name);
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/*
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** Find a "name" for the constant 'c'.
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*/
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static void kname (const Proto *p, int c, const char **name) {
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TValue *kvalue = &p->k[c];
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*name = (ttisstring(kvalue)) ? svalue(kvalue) : "?";
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}
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/*
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** Find a "name" for the register 'c'.
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*/
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static void rname (const Proto *p, int pc, int c, const char **name) {
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const char *what = getobjname(p, pc, c, name); /* search for 'c' */
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if (!(what && *what == 'c')) /* did not find a constant name? */
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*name = "?";
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}
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/*
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** Find a "name" for a 'C' value in an RK instruction.
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*/
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static void rkname (const Proto *p, int pc, Instruction i, const char **name) {
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int c = GETARG_C(i); /* key index */
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if (GETARG_k(i)) /* is 'c' a constant? */
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kname(p, c, name);
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else /* 'c' is a register */
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rname(p, pc, c, name);
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}
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static int filterpc (int pc, int jmptarget) {
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if (pc < jmptarget) /* is code conditional (inside a jump)? */
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return -1; /* cannot know who sets that register */
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else return pc; /* current position sets that register */
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}
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/*
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** Try to find last instruction before 'lastpc' that modified register 'reg'.
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*/
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static int findsetreg (const Proto *p, int lastpc, int reg) {
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int pc;
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int setreg = -1; /* keep last instruction that changed 'reg' */
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int jmptarget = 0; /* any code before this address is conditional */
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if (testMMMode(GET_OPCODE(p->code[lastpc])))
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||
lastpc--; /* previous instruction was not actually executed */
|
||
for (pc = 0; pc < lastpc; pc++) {
|
||
Instruction i = p->code[pc];
|
||
OpCode op = GET_OPCODE(i);
|
||
int a = GETARG_A(i);
|
||
int change; /* true if current instruction changed 'reg' */
|
||
switch (op) {
|
||
case OP_LOADNIL: { /* set registers from 'a' to 'a+b' */
|
||
int b = GETARG_B(i);
|
||
change = (a <= reg && reg <= a + b);
|
||
break;
|
||
}
|
||
case OP_TFORCALL: { /* affect all regs above its base */
|
||
change = (reg >= a + 2);
|
||
break;
|
||
}
|
||
case OP_CALL:
|
||
case OP_TAILCALL: { /* affect all registers above base */
|
||
change = (reg >= a);
|
||
break;
|
||
}
|
||
case OP_JMP: { /* doesn't change registers, but changes 'jmptarget' */
|
||
int b = GETARG_sJ(i);
|
||
int dest = pc + 1 + b;
|
||
/* jump does not skip 'lastpc' and is larger than current one? */
|
||
if (dest <= lastpc && dest > jmptarget)
|
||
jmptarget = dest; /* update 'jmptarget' */
|
||
change = 0;
|
||
break;
|
||
}
|
||
default: /* any instruction that sets A */
|
||
change = (testAMode(op) && reg == a);
|
||
break;
|
||
}
|
||
if (change)
|
||
setreg = filterpc(pc, jmptarget);
|
||
}
|
||
return setreg;
|
||
}
|
||
|
||
|
||
/*
|
||
** Check whether table being indexed by instruction 'i' is the
|
||
** environment '_ENV'
|
||
*/
|
||
static const char *gxf (const Proto *p, int pc, Instruction i, int isup) {
|
||
int t = GETARG_B(i); /* table index */
|
||
const char *name; /* name of indexed variable */
|
||
if (isup) /* is an upvalue? */
|
||
name = upvalname(p, t);
|
||
else
|
||
getobjname(p, pc, t, &name);
|
||
return (name && strcmp(name, LUA_ENV) == 0) ? "global" : "field";
|
||
}
|
||
|
||
|
||
static const char *getobjname (const Proto *p, int lastpc, int reg,
|
||
const char **name) {
|
||
int pc;
|
||
*name = luaF_getlocalname(p, reg + 1, lastpc);
|
||
if (*name) /* is a local? */
|
||
return "local";
|
||
/* else try symbolic execution */
|
||
pc = findsetreg(p, lastpc, reg);
|
||
if (pc != -1) { /* could find instruction? */
|
||
Instruction i = p->code[pc];
|
||
OpCode op = GET_OPCODE(i);
|
||
switch (op) {
|
||
case OP_MOVE: {
|
||
int b = GETARG_B(i); /* move from 'b' to 'a' */
|
||
if (b < GETARG_A(i))
|
||
return getobjname(p, pc, b, name); /* get name for 'b' */
|
||
break;
|
||
}
|
||
case OP_GETTABUP: {
|
||
int k = GETARG_C(i); /* key index */
|
||
kname(p, k, name);
|
||
return gxf(p, pc, i, 1);
|
||
}
|
||
case OP_GETTABLE: {
|
||
int k = GETARG_C(i); /* key index */
|
||
rname(p, pc, k, name);
|
||
return gxf(p, pc, i, 0);
|
||
}
|
||
case OP_GETI: {
|
||
*name = "integer index";
|
||
return "field";
|
||
}
|
||
case OP_GETFIELD: {
|
||
int k = GETARG_C(i); /* key index */
|
||
kname(p, k, name);
|
||
return gxf(p, pc, i, 0);
|
||
}
|
||
case OP_GETUPVAL: {
|
||
*name = upvalname(p, GETARG_B(i));
|
||
return "upvalue";
|
||
}
|
||
case OP_LOADK:
|
||
case OP_LOADKX: {
|
||
int b = (op == OP_LOADK) ? GETARG_Bx(i)
|
||
: GETARG_Ax(p->code[pc + 1]);
|
||
if (ttisstring(&p->k[b])) {
|
||
*name = svalue(&p->k[b]);
|
||
return "constant";
|
||
}
|
||
break;
|
||
}
|
||
case OP_SELF: {
|
||
rkname(p, pc, i, name);
|
||
return "method";
|
||
}
|
||
default: break; /* go through to return NULL */
|
||
}
|
||
}
|
||
return NULL; /* could not find reasonable name */
|
||
}
|
||
|
||
|
||
/*
|
||
** Try to find a name for a function based on the code that called it.
|
||
** (Only works when function was called by a Lua function.)
|
||
** Returns what the name is (e.g., "for iterator", "method",
|
||
** "metamethod") and sets '*name' to point to the name.
|
||
*/
|
||
static const char *funcnamefromcode (lua_State *L, CallInfo *ci,
|
||
const char **name) {
|
||
TMS tm = (TMS)0; /* (initial value avoids warnings) */
|
||
const Proto *p = ci_func(ci)->p; /* calling function */
|
||
int pc = currentpc(ci); /* calling instruction index */
|
||
Instruction i = p->code[pc]; /* calling instruction */
|
||
if (ci->callstatus & CIST_HOOKED) { /* was it called inside a hook? */
|
||
*name = "?";
|
||
return "hook";
|
||
}
|
||
switch (GET_OPCODE(i)) {
|
||
case OP_CALL:
|
||
case OP_TAILCALL:
|
||
return getobjname(p, pc, GETARG_A(i), name); /* get function name */
|
||
case OP_TFORCALL: { /* for iterator */
|
||
*name = "for iterator";
|
||
return "for iterator";
|
||
}
|
||
/* other instructions can do calls through metamethods */
|
||
case OP_SELF: case OP_GETTABUP: case OP_GETTABLE:
|
||
case OP_GETI: case OP_GETFIELD:
|
||
tm = TM_INDEX;
|
||
break;
|
||
case OP_SETTABUP: case OP_SETTABLE: case OP_SETI: case OP_SETFIELD:
|
||
tm = TM_NEWINDEX;
|
||
break;
|
||
case OP_MMBIN: case OP_MMBINI: case OP_MMBINK: {
|
||
tm = cast(TMS, GETARG_C(i));
|
||
break;
|
||
}
|
||
case OP_UNM: tm = TM_UNM; break;
|
||
case OP_BNOT: tm = TM_BNOT; break;
|
||
case OP_LEN: tm = TM_LEN; break;
|
||
case OP_CONCAT: tm = TM_CONCAT; break;
|
||
case OP_EQ: tm = TM_EQ; break;
|
||
/* no cases for OP_EQI and OP_EQK, as they don't call metamethods */
|
||
case OP_LT: case OP_LTI: case OP_GTI: tm = TM_LT; break;
|
||
case OP_LE: case OP_LEI: case OP_GEI: tm = TM_LE; break;
|
||
case OP_CLOSE: case OP_RETURN: tm = TM_CLOSE; break;
|
||
default:
|
||
return NULL; /* cannot find a reasonable name */
|
||
}
|
||
*name = getstr(G(L)->tmname[tm]) + 2;
|
||
return "metamethod";
|
||
}
|
||
|
||
/* }====================================================== */
|
||
|
||
|
||
|
||
/*
|
||
** Check whether pointer 'o' points to some value in the stack
|
||
** frame of the current function. Because 'o' may not point to a
|
||
** value in this stack, we cannot compare it with the region
|
||
** boundaries (undefined behaviour in ISO C).
|
||
*/
|
||
static int isinstack (CallInfo *ci, const TValue *o) {
|
||
StkId pos;
|
||
for (pos = ci->func + 1; pos < ci->top; pos++) {
|
||
if (o == s2v(pos))
|
||
return 1;
|
||
}
|
||
return 0; /* not found */
|
||
}
|
||
|
||
|
||
/*
|
||
** Checks whether value 'o' came from an upvalue. (That can only happen
|
||
** with instructions OP_GETTABUP/OP_SETTABUP, which operate directly on
|
||
** upvalues.)
|
||
*/
|
||
static const char *getupvalname (CallInfo *ci, const TValue *o,
|
||
const char **name) {
|
||
LClosure *c = ci_func(ci);
|
||
int i;
|
||
for (i = 0; i < c->nupvalues; i++) {
|
||
if (c->upvals[i]->v == o) {
|
||
*name = upvalname(c->p, i);
|
||
return "upvalue";
|
||
}
|
||
}
|
||
return NULL;
|
||
}
|
||
|
||
|
||
static const char *varinfo (lua_State *L, const TValue *o) {
|
||
const char *name = NULL; /* to avoid warnings */
|
||
CallInfo *ci = L->ci;
|
||
const char *kind = NULL;
|
||
if (isLua(ci)) {
|
||
kind = getupvalname(ci, o, &name); /* check whether 'o' is an upvalue */
|
||
if (!kind && isinstack(ci, o)) /* no? try a register */
|
||
kind = getobjname(ci_func(ci)->p, currentpc(ci),
|
||
cast_int(cast(StkId, o) - (ci->func + 1)), &name);
|
||
}
|
||
return (kind) ? luaO_pushfstring(L, " (%s '%s')", kind, name) : "";
|
||
}
|
||
|
||
|
||
l_noret luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
|
||
const char *t = luaT_objtypename(L, o);
|
||
luaG_runerror(L, "attempt to %s a %s value%s", op, t, varinfo(L, o));
|
||
}
|
||
|
||
|
||
l_noret luaG_callerror (lua_State *L, const TValue *o) {
|
||
CallInfo *ci = L->ci;
|
||
const char *name = NULL; /* to avoid warnings */
|
||
const char *what = (isLua(ci)) ? funcnamefromcode(L, ci, &name) : NULL;
|
||
if (what != NULL) {
|
||
const char *t = luaT_objtypename(L, o);
|
||
luaG_runerror(L, "%s '%s' is not callable (a %s value)", what, name, t);
|
||
}
|
||
else
|
||
luaG_typeerror(L, o, "call");
|
||
}
|
||
|
||
|
||
l_noret luaG_forerror (lua_State *L, const TValue *o, const char *what) {
|
||
luaG_runerror(L, "bad 'for' %s (number expected, got %s)",
|
||
what, luaT_objtypename(L, o));
|
||
}
|
||
|
||
|
||
l_noret luaG_concaterror (lua_State *L, const TValue *p1, const TValue *p2) {
|
||
if (ttisstring(p1) || cvt2str(p1)) p1 = p2;
|
||
luaG_typeerror(L, p1, "concatenate");
|
||
}
|
||
|
||
|
||
l_noret luaG_opinterror (lua_State *L, const TValue *p1,
|
||
const TValue *p2, const char *msg) {
|
||
if (!ttisnumber(p1)) /* first operand is wrong? */
|
||
p2 = p1; /* now second is wrong */
|
||
luaG_typeerror(L, p2, msg);
|
||
}
|
||
|
||
|
||
/*
|
||
** Error when both values are convertible to numbers, but not to integers
|
||
*/
|
||
l_noret luaG_tointerror (lua_State *L, const TValue *p1, const TValue *p2) {
|
||
lua_Integer temp;
|
||
if (!luaV_tointegerns(p1, &temp, LUA_FLOORN2I))
|
||
p2 = p1;
|
||
luaG_runerror(L, "number%s has no integer representation", varinfo(L, p2));
|
||
}
|
||
|
||
|
||
l_noret luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
|
||
const char *t1 = luaT_objtypename(L, p1);
|
||
const char *t2 = luaT_objtypename(L, p2);
|
||
if (strcmp(t1, t2) == 0)
|
||
luaG_runerror(L, "attempt to compare two %s values", t1);
|
||
else
|
||
luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
|
||
}
|
||
|
||
|
||
/* add src:line information to 'msg' */
|
||
const char *luaG_addinfo (lua_State *L, const char *msg, TString *src,
|
||
int line) {
|
||
char buff[LUA_IDSIZE];
|
||
if (src)
|
||
luaO_chunkid(buff, getstr(src), tsslen(src));
|
||
else { /* no source available; use "?" instead */
|
||
buff[0] = '?'; buff[1] = '\0';
|
||
}
|
||
return luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
|
||
}
|
||
|
||
|
||
l_noret luaG_errormsg (lua_State *L) {
|
||
if (L->errfunc != 0) { /* is there an error handling function? */
|
||
StkId errfunc = restorestack(L, L->errfunc);
|
||
lua_assert(ttisfunction(s2v(errfunc)));
|
||
setobjs2s(L, L->top, L->top - 1); /* move argument */
|
||
setobjs2s(L, L->top - 1, errfunc); /* push function */
|
||
L->top++; /* assume EXTRA_STACK */
|
||
luaD_callnoyield(L, L->top - 2, 1); /* call it */
|
||
}
|
||
luaD_throw(L, LUA_ERRRUN);
|
||
}
|
||
|
||
|
||
l_noret luaG_runerror (lua_State *L, const char *fmt, ...) {
|
||
CallInfo *ci = L->ci;
|
||
const char *msg;
|
||
va_list argp;
|
||
luaC_checkGC(L); /* error message uses memory */
|
||
va_start(argp, fmt);
|
||
msg = luaO_pushvfstring(L, fmt, argp); /* format message */
|
||
va_end(argp);
|
||
if (isLua(ci)) /* if Lua function, add source:line information */
|
||
luaG_addinfo(L, msg, ci_func(ci)->p->source, getcurrentline(ci));
|
||
luaG_errormsg(L);
|
||
}
|
||
|
||
|
||
/*
|
||
** Check whether new instruction 'newpc' is in a different line from
|
||
** previous instruction 'oldpc'. More often than not, 'newpc' is only
|
||
** one or a few instructions after 'oldpc' (it must be after, see
|
||
** caller), so try to avoid calling 'luaG_getfuncline'. If they are
|
||
** too far apart, there is a good chance of a ABSLINEINFO in the way,
|
||
** so it goes directly to 'luaG_getfuncline'.
|
||
*/
|
||
static int changedline (const Proto *p, int oldpc, int newpc) {
|
||
if (p->lineinfo == NULL) /* no debug information? */
|
||
return 0;
|
||
if (newpc - oldpc < MAXIWTHABS / 2) { /* not too far apart? */
|
||
int delta = 0; /* line diference */
|
||
int pc = oldpc;
|
||
for (;;) {
|
||
int lineinfo = p->lineinfo[++pc];
|
||
if (lineinfo == ABSLINEINFO)
|
||
break; /* cannot compute delta; fall through */
|
||
delta += lineinfo;
|
||
if (pc == newpc)
|
||
return (delta != 0); /* delta computed successfully */
|
||
}
|
||
}
|
||
/* either instructions are too far apart or there is an absolute line
|
||
info in the way; compute line difference explicitly */
|
||
return (luaG_getfuncline(p, oldpc) != luaG_getfuncline(p, newpc));
|
||
}
|
||
|
||
|
||
/*
|
||
** Traces the execution of a Lua function. Called before the execution
|
||
** of each opcode, when debug is on. 'L->oldpc' stores the last
|
||
** instruction traced, to detect line changes. When entering a new
|
||
** function, 'npci' will be zero and will test as a new line whatever
|
||
** the value of 'oldpc'. Some exceptional conditions may return to
|
||
** a function without setting 'oldpc'. In that case, 'oldpc' may be
|
||
** invalid; if so, use zero as a valid value. (A wrong but valid 'oldpc'
|
||
** at most causes an extra call to a line hook.)
|
||
** This function is not "Protected" when called, so it should correct
|
||
** 'L->top' before calling anything that can run the GC.
|
||
*/
|
||
int luaG_traceexec (lua_State *L, const Instruction *pc) {
|
||
CallInfo *ci = L->ci;
|
||
lu_byte mask = L->hookmask;
|
||
const Proto *p = ci_func(ci)->p;
|
||
int counthook;
|
||
if (!(mask & (LUA_MASKLINE | LUA_MASKCOUNT))) { /* no hooks? */
|
||
ci->u.l.trap = 0; /* don't need to stop again */
|
||
return 0; /* turn off 'trap' */
|
||
}
|
||
pc++; /* reference is always next instruction */
|
||
ci->u.l.savedpc = pc; /* save 'pc' */
|
||
counthook = (--L->hookcount == 0 && (mask & LUA_MASKCOUNT));
|
||
if (counthook)
|
||
resethookcount(L); /* reset count */
|
||
else if (!(mask & LUA_MASKLINE))
|
||
return 1; /* no line hook and count != 0; nothing to be done now */
|
||
if (ci->callstatus & CIST_HOOKYIELD) { /* called hook last time? */
|
||
ci->callstatus &= ~CIST_HOOKYIELD; /* erase mark */
|
||
return 1; /* do not call hook again (VM yielded, so it did not move) */
|
||
}
|
||
if (!isIT(*(ci->u.l.savedpc - 1))) /* top not being used? */
|
||
L->top = ci->top; /* correct top */
|
||
if (counthook)
|
||
luaD_hook(L, LUA_HOOKCOUNT, -1, 0, 0); /* call count hook */
|
||
if (mask & LUA_MASKLINE) {
|
||
/* 'L->oldpc' may be invalid; use zero in this case */
|
||
int oldpc = (L->oldpc < p->sizecode) ? L->oldpc : 0;
|
||
int npci = pcRel(pc, p);
|
||
if (npci <= oldpc || /* call hook when jump back (loop), */
|
||
changedline(p, oldpc, npci)) { /* or when enter new line */
|
||
int newline = luaG_getfuncline(p, npci);
|
||
luaD_hook(L, LUA_HOOKLINE, newline, 0, 0); /* call line hook */
|
||
}
|
||
L->oldpc = npci; /* 'pc' of last call to line hook */
|
||
}
|
||
if (L->status == LUA_YIELD) { /* did hook yield? */
|
||
if (counthook)
|
||
L->hookcount = 1; /* undo decrement to zero */
|
||
ci->u.l.savedpc--; /* undo increment (resume will increment it again) */
|
||
ci->callstatus |= CIST_HOOKYIELD; /* mark that it yielded */
|
||
luaD_throw(L, LUA_YIELD);
|
||
}
|
||
return 1; /* keep 'trap' on */
|
||
}
|
||
|