lua/ldebug.c
2000-08-08 17:42:07 -03:00

414 lines
10 KiB
C

/*
** $Id: ldebug.c,v 1.29 2000/08/08 18:26:05 roberto Exp roberto $
** Debug Interface
** See Copyright Notice in lua.h
*/
#include <stdlib.h>
#define LUA_REENTRANT
#include "lua.h"
#include "lapi.h"
#include "lauxlib.h"
#include "lcode.h"
#include "ldebug.h"
#include "ldo.h"
#include "lfunc.h"
#include "lobject.h"
#include "lopcodes.h"
#include "lstate.h"
#include "ltable.h"
#include "ltm.h"
#include "luadebug.h"
static void setnormalized (TObject *d, const TObject *s) {
switch (s->ttype) {
case TAG_CMARK: {
clvalue(d) = clvalue(s);
ttype(d) = TAG_CCLOSURE;
break;
}
case TAG_LMARK: {
clvalue(d) = infovalue(s)->func;
ttype(d) = TAG_LCLOSURE;
break;
}
default: *d = *s;
}
}
lua_Hook lua_setcallhook (lua_State *L, lua_Hook func) {
lua_Hook oldhook = L->callhook;
L->callhook = func;
return oldhook;
}
lua_Hook lua_setlinehook (lua_State *L, lua_Hook func) {
lua_Hook oldhook = L->linehook;
L->linehook = func;
return oldhook;
}
static StkId aux_stackedfunction (lua_State *L, int level, StkId top) {
int i;
for (i = (top-1)-L->stack; i>=0; i--) {
if (is_T_MARK(L->stack[i].ttype)) {
if (level == 0)
return L->stack+i;
level--;
}
}
return NULL;
}
int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
StkId f = aux_stackedfunction(L, level, L->top);
if (f == NULL) return 0; /* there is no such level */
else {
ar->_func = f;
return 1;
}
}
static int lua_nups (StkId f) {
switch (ttype(f)) {
case TAG_LCLOSURE: case TAG_CCLOSURE: case TAG_CMARK:
return clvalue(f)->nupvalues;
case TAG_LMARK:
return infovalue(f)->func->nupvalues;
default:
return 0;
}
}
int luaG_getline (int *lineinfo, int pc, int refline, int *prefi) {
int refi = prefi ? *prefi : 0;
if (lineinfo[refi] < 0)
refline += -lineinfo[refi++];
LUA_ASSERT(lineinfo[refi] >= 0, "invalid line info");
while (lineinfo[refi] > pc) {
refline--;
refi--;
if (lineinfo[refi] < 0)
refline -= -lineinfo[refi--];
LUA_ASSERT(lineinfo[refi] >= 0, "invalid line info");
}
for (;;) {
int nextline = refline + 1;
int nextref = refi + 1;
if (lineinfo[nextref] < 0)
nextline += -lineinfo[nextref++];
LUA_ASSERT(lineinfo[nextref] >= 0, "invalid line info");
if (lineinfo[nextref] > pc)
break;
refline = nextline;
refi = nextref;
}
if (prefi) *prefi = refi;
return refline;
}
static int lua_currentpc (StkId f) {
CallInfo *ci = infovalue(f);
LUA_ASSERT(ttype(f) == TAG_LMARK, "function has no pc");
return (*ci->pc - 1) - ci->func->f.l->code;
}
static int lua_currentline (StkId f) {
if (ttype(f) != TAG_LMARK)
return -1; /* only active lua functions have current-line information */
else {
CallInfo *ci = infovalue(f);
int *lineinfo = ci->func->f.l->lineinfo;
return luaG_getline(lineinfo, lua_currentpc(f), 1, NULL);
}
}
static Proto *getluaproto (StkId f) {
return (ttype(f) == TAG_LMARK) ? infovalue(f)->func->f.l : NULL;
}
int lua_getlocal (lua_State *L, const lua_Debug *ar, lua_Localvar *v) {
StkId f = ar->_func;
Proto *fp = getluaproto(f);
if (!fp) return 0; /* `f' is not a Lua function? */
v->name = luaF_getlocalname(fp, v->index, lua_currentpc(f));
if (!v->name) return 0;
v->value = luaA_putluaObject(L, (f+1)+(v->index-1));
return 1;
}
int lua_setlocal (lua_State *L, const lua_Debug *ar, lua_Localvar *v) {
StkId f = ar->_func;
Proto *fp = getluaproto(f);
UNUSED(L);
if (!fp) return 0; /* `f' is not a Lua function? */
v->name = luaF_getlocalname(fp, v->index, lua_currentpc(f));
if (!v->name || v->name[0] == '*') return 0; /* `*' starts private locals */
*((f+1)+(v->index-1)) = *v->value;
return 1;
}
static void lua_funcinfo (lua_Debug *ar, StkId func) {
switch (ttype(func)) {
case TAG_LCLOSURE:
ar->source = clvalue(func)->f.l->source->str;
ar->linedefined = clvalue(func)->f.l->lineDefined;
ar->what = "Lua";
break;
case TAG_LMARK:
ar->source = infovalue(func)->func->f.l->source->str;
ar->linedefined = infovalue(func)->func->f.l->lineDefined;
ar->what = "Lua";
break;
case TAG_CCLOSURE: case TAG_CMARK:
ar->source = "(C)";
ar->linedefined = -1;
ar->what = "C";
break;
default:
LUA_INTERNALERROR("invalid `func' value");
}
if (ar->linedefined == 0)
ar->what = "main";
}
static const char *travtagmethods (lua_State *L, const TObject *o) {
int e;
for (e=0; e<IM_N; e++) {
int t;
for (t=0; t<=L->last_tag; t++)
if (luaO_equalObj(o, luaT_getim(L, t,e)))
return luaT_eventname[e];
}
return NULL;
}
static const char *travglobals (lua_State *L, const TObject *o) {
Hash *g = L->gt;
int i;
for (i=0; i<=g->size; i++) {
if (luaO_equalObj(o, val(node(g, i))) &&
ttype(key(node(g, i))) == TAG_STRING)
return tsvalue(key(node(g, i)))->str;
}
return NULL;
}
static void lua_getobjname (lua_State *L, StkId f, lua_Debug *ar) {
TObject o;
setnormalized(&o, f);
/* try to find a name for given function */
if ((ar->name = travglobals(L, &o)) != NULL)
ar->namewhat = "global";
/* not found: try tag methods */
else if ((ar->name = travtagmethods(L, &o)) != NULL)
ar->namewhat = "tag-method";
else ar->namewhat = ""; /* not found at all */
}
int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
StkId func;
if (*what != '>')
func = ar->_func;
else {
what++; /* skip the '>' */
func = ar->func;
}
for (; *what; what++) {
switch (*what) {
case 'S':
lua_funcinfo(ar, func);
break;
case 'l':
ar->currentline = lua_currentline(func);
break;
case 'u':
ar->nups = lua_nups(func);
break;
case 'n':
lua_getobjname(L, func, ar);
break;
case 'f':
setnormalized(L->top, func);
incr_top;
ar->func = lua_pop(L);
break;
default: return 0; /* invalid option */
}
}
return 1;
}
/*
** {======================================================
** Symbolic Execution
** =======================================================
*/
static Instruction luaG_symbexec (const Proto *pt, int lastpc, int stackpos) {
int stack[MAXSTACK]; /* stores last instruction that changes each value */
const Instruction *code = pt->code;
int top = pt->numparams;
int pc = 0;
if (pt->is_vararg) /* varargs? */
top++; /* `arg' */
while (pc < lastpc) {
const Instruction i = code[pc++];
LUA_ASSERT(top <= pt->maxstacksize, "wrong stack");
switch (GET_OPCODE(i)) {
case OP_RETURN: {
LUA_ASSERT(top >= GETARG_U(i), "wrong stack");
top = GETARG_U(i);
break;
}
case OP_CALL: {
int nresults = GETARG_B(i);
if (nresults == MULT_RET) nresults = 1;
LUA_ASSERT(top >= GETARG_A(i), "wrong stack");
top = GETARG_A(i);
while (nresults--)
stack[top++] = pc-1;
break;
}
case OP_TAILCALL: {
LUA_ASSERT(top >= GETARG_A(i), "wrong stack");
top = GETARG_B(i);
break;
}
case OP_PUSHNIL: {
int n;
for (n=0; n<GETARG_U(i); n++)
stack[top++] = pc-1;
break;
}
case OP_POP: {
top -= GETARG_U(i);
break;
}
case OP_SETTABLE:
case OP_SETLIST: {
top -= GETARG_B(i);
break;
}
case OP_SETMAP: {
top -= 2*GETARG_U(i);
break;
}
case OP_CONCAT: {
top -= GETARG_U(i);
stack[top++] = pc-1;
break;
}
case OP_JMPONT:
case OP_JMPONF: {
int newpc = pc + GETARG_S(i);
if (lastpc < newpc)
top--; /* original code did not jump; condition was false */
else {
stack[top-1] = pc-1; /* value generated by or-and */
pc = newpc; /* do the jump */
}
break;
}
case OP_PUSHNILJMP: {
break; /* do not `push', to compensate next instruction */
}
case OP_CLOSURE: {
top -= GETARG_B(i);
stack[top++] = pc-1;
break;
}
default: {
int n;
LUA_ASSERT(luaK_opproperties[GET_OPCODE(i)].push != VD,
"invalid opcode for default");
top -= luaK_opproperties[GET_OPCODE(i)].pop;
LUA_ASSERT(top >= 0, "wrong stack");
for (n=0; n<luaK_opproperties[GET_OPCODE(i)].push; n++)
stack[top++] = pc-1;
}
}
}
return code[stack[stackpos]];
}
static const char *getname (lua_State *L, StkId obj, const char **name) {
StkId func = aux_stackedfunction(L, 0, obj);
if (func == NULL || ttype(func) != TAG_LMARK)
return NULL; /* not a Lua function */
else {
Proto *p = infovalue(func)->func->f.l;
int pc = lua_currentpc(func);
int stackpos = obj - (func+1); /* func+1 == function base */
Instruction i = luaG_symbexec(p, pc, stackpos);
switch (GET_OPCODE(i)) {
case OP_GETGLOBAL: {
*name = p->kstr[GETARG_U(i)]->str;
return "global";
}
case OP_GETLOCAL: {
*name = luaF_getlocalname(p, GETARG_U(i)+1, pc);
LUA_ASSERT(*name, "local must exist");
return "local";
}
case OP_PUSHSELF:
case OP_GETDOTTED: {
*name = p->kstr[GETARG_U(i)]->str;
return "field";
}
default:
return NULL; /* no usefull name found */
}
}
}
/* }====================================================== */
static void call_index_error (lua_State *L, StkId o, const char *op,
const char *tp) {
const char *name;
const char *kind = getname(L, o, &name);
if (kind)
luaL_verror(L, "%s `%s' is not a %s", kind, name, tp);
else
luaL_verror(L, "attempt to %.10s a %.10s value", op, lua_type(L, o));
}
void luaG_callerror (lua_State *L, StkId func) {
call_index_error(L, func, "call", "function");
}
void luaG_indexerror (lua_State *L, StkId t) {
call_index_error(L, t, "index", "table");
}