diff options
Diffstat (limited to 'src/ldebug.c')
| -rw-r--r-- | src/ldebug.c | 638 |
1 files changed, 638 insertions, 0 deletions
diff --git a/src/ldebug.c b/src/ldebug.c new file mode 100644 index 0000000..50ad3d3 --- /dev/null +++ b/src/ldebug.c @@ -0,0 +1,638 @@ +/* +** $Id: ldebug.c,v 2.29.1.6 2008/05/08 16:56:26 roberto Exp $ +** Debug Interface +** See Copyright Notice in lua.h +*/ + + +#include <stdarg.h> +#include <stddef.h> +#include <string.h> + + +#define ldebug_c +#define LUA_CORE + +#include "lua.h" + +#include "lapi.h" +#include "lcode.h" +#include "ldebug.h" +#include "ldo.h" +#include "lfunc.h" +#include "lobject.h" +#include "lopcodes.h" +#include "lstate.h" +#include "lstring.h" +#include "ltable.h" +#include "ltm.h" +#include "lvm.h" + + + +static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name); + + +static int currentpc (lua_State *L, CallInfo *ci) { + if (!isLua(ci)) return -1; /* function is not a Lua function? */ + if (ci == L->ci) + ci->savedpc = L->savedpc; + return pcRel(ci->savedpc, ci_func(ci)->l.p); +} + + +static int currentline (lua_State *L, CallInfo *ci) { + int pc = currentpc(L, ci); + if (pc < 0) + return -1; /* only active lua functions have current-line information */ + else + return getline(ci_func(ci)->l.p, pc); +} + + +/* +** this function can be called asynchronous (e.g. during a signal) +*/ +LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) { + if (func == NULL || mask == 0) { /* turn off hooks? */ + mask = 0; + func = NULL; + } + L->hook = func; + L->basehookcount = count; + resethookcount(L); + L->hookmask = cast_byte(mask); + return 1; +} + + +LUA_API lua_Hook lua_gethook (lua_State *L) { + return L->hook; +} + + +LUA_API int lua_gethookmask (lua_State *L) { + return L->hookmask; +} + + +LUA_API int lua_gethookcount (lua_State *L) { + return L->basehookcount; +} + + +LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) { + int status; + CallInfo *ci; + lua_lock(L); + for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) { + level--; + if (f_isLua(ci)) /* Lua function? */ + level -= ci->tailcalls; /* skip lost tail calls */ + } + if (level == 0 && ci > L->base_ci) { /* level found? */ + status = 1; + ar->i_ci = cast_int(ci - L->base_ci); + } + else if (level < 0) { /* level is of a lost tail call? */ + status = 1; + ar->i_ci = 0; + } + else status = 0; /* no such level */ + lua_unlock(L); + return status; +} + + +static Proto *getluaproto (CallInfo *ci) { + return (isLua(ci) ? ci_func(ci)->l.p : NULL); +} + + +static const char *findlocal (lua_State *L, CallInfo *ci, int n) { + const char *name; + Proto *fp = getluaproto(ci); + if (fp && (name = luaF_getlocalname(fp, n, currentpc(L, ci))) != NULL) + return name; /* is a local variable in a Lua function */ + else { + StkId limit = (ci == L->ci) ? L->top : (ci+1)->func; + if (limit - ci->base >= n && n > 0) /* is 'n' inside 'ci' stack? */ + return "(*temporary)"; + else + return NULL; + } +} + + +LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) { + CallInfo *ci = L->base_ci + ar->i_ci; + const char *name = findlocal(L, ci, n); + lua_lock(L); + if (name) + luaA_pushobject(L, ci->base + (n - 1)); + lua_unlock(L); + return name; +} + + +LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) { + CallInfo *ci = L->base_ci + ar->i_ci; + const char *name = findlocal(L, ci, n); + lua_lock(L); + if (name) + setobjs2s(L, ci->base + (n - 1), L->top - 1); + L->top--; /* pop value */ + lua_unlock(L); + return name; +} + + +static void funcinfo (lua_Debug *ar, Closure *cl) { + if (cl->c.isC) { + ar->source = "=[C]"; + ar->linedefined = -1; + ar->lastlinedefined = -1; + ar->what = "C"; + } + else { + ar->source = getstr(cl->l.p->source); + ar->linedefined = cl->l.p->linedefined; + ar->lastlinedefined = cl->l.p->lastlinedefined; + ar->what = (ar->linedefined == 0) ? "main" : "Lua"; + } + luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE); +} + + +static void info_tailcall (lua_Debug *ar) { + ar->name = ar->namewhat = ""; + ar->what = "tail"; + ar->lastlinedefined = ar->linedefined = ar->currentline = -1; + ar->source = "=(tail call)"; + luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE); + ar->nups = 0; +} + + +static void collectvalidlines (lua_State *L, Closure *f) { + if (f == NULL || f->c.isC) { + setnilvalue(L->top); + } + else { + Table *t = luaH_new(L, 0, 0); + int *lineinfo = f->l.p->lineinfo; + int i; + for (i=0; i<f->l.p->sizelineinfo; i++) + setbvalue(luaH_setnum(L, t, lineinfo[i]), 1); + sethvalue(L, L->top, t); + } + incr_top(L); +} + + +static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar, + Closure *f, CallInfo *ci) { + int status = 1; + if (f == NULL) { + info_tailcall(ar); + return status; + } + for (; *what; what++) { + switch (*what) { + case 'S': { + funcinfo(ar, f); + break; + } + case 'l': { + ar->currentline = (ci) ? currentline(L, ci) : -1; + break; + } + case 'u': { + ar->nups = f->c.nupvalues; + break; + } + case 'n': { + ar->namewhat = (ci) ? getfuncname(L, ci, &ar->name) : NULL; + if (ar->namewhat == NULL) { + ar->namewhat = ""; /* not found */ + ar->name = NULL; + } + break; + } + case 'L': + case 'f': /* handled by lua_getinfo */ + break; + default: status = 0; /* invalid option */ + } + } + return status; +} + + +LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) { + int status; + Closure *f = NULL; + CallInfo *ci = NULL; + lua_lock(L); + if (*what == '>') { + StkId func = L->top - 1; + luai_apicheck(L, ttisfunction(func)); + what++; /* skip the '>' */ + f = clvalue(func); + L->top--; /* pop function */ + } + else if (ar->i_ci != 0) { /* no tail call? */ + ci = L->base_ci + ar->i_ci; + lua_assert(ttisfunction(ci->func)); + f = clvalue(ci->func); + } + status = auxgetinfo(L, what, ar, f, ci); + if (strchr(what, 'f')) { + if (f == NULL) setnilvalue(L->top); + else setclvalue(L, L->top, f); + incr_top(L); + } + if (strchr(what, 'L')) + collectvalidlines(L, f); + lua_unlock(L); + return status; +} + + +/* +** {====================================================== +** Symbolic Execution and code checker +** ======================================================= +*/ + +#define check(x) if (!(x)) return 0; + +#define checkjump(pt,pc) check(0 <= pc && pc < pt->sizecode) + +#define checkreg(pt,reg) check((reg) < (pt)->maxstacksize) + + + +static int precheck (const Proto *pt) { + check(pt->maxstacksize <= MAXSTACK); + check(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize); + check(!(pt->is_vararg & VARARG_NEEDSARG) || + (pt->is_vararg & VARARG_HASARG)); + check(pt->sizeupvalues <= pt->nups); + check(pt->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0); + check(pt->sizecode > 0 && GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN); + return 1; +} + + +#define checkopenop(pt,pc) luaG_checkopenop((pt)->code[(pc)+1]) + +int luaG_checkopenop (Instruction i) { + switch (GET_OPCODE(i)) { + case OP_CALL: + case OP_TAILCALL: + case OP_RETURN: + case OP_SETLIST: { + check(GETARG_B(i) == 0); + return 1; + } + default: return 0; /* invalid instruction after an open call */ + } +} + + +static int checkArgMode (const Proto *pt, int r, enum OpArgMask mode) { + switch (mode) { + case OpArgN: check(r == 0); break; + case OpArgU: break; + case OpArgR: checkreg(pt, r); break; + case OpArgK: + check(ISK(r) ? INDEXK(r) < pt->sizek : r < pt->maxstacksize); + break; + } + return 1; +} + + +static Instruction symbexec (const Proto *pt, int lastpc, int reg) { + int pc; + int last; /* stores position of last instruction that changed `reg' */ + last = pt->sizecode-1; /* points to final return (a `neutral' instruction) */ + check(precheck(pt)); + for (pc = 0; pc < lastpc; pc++) { + Instruction i = pt->code[pc]; + OpCode op = GET_OPCODE(i); + int a = GETARG_A(i); + int b = 0; + int c = 0; + check(op < NUM_OPCODES); + checkreg(pt, a); + switch (getOpMode(op)) { + case iABC: { + b = GETARG_B(i); + c = GETARG_C(i); + check(checkArgMode(pt, b, getBMode(op))); + check(checkArgMode(pt, c, getCMode(op))); + break; + } + case iABx: { + b = GETARG_Bx(i); + if (getBMode(op) == OpArgK) check(b < pt->sizek); + break; + } + case iAsBx: { + b = GETARG_sBx(i); + if (getBMode(op) == OpArgR) { + int dest = pc+1+b; + check(0 <= dest && dest < pt->sizecode); + if (dest > 0) { + int j; + /* check that it does not jump to a setlist count; this + is tricky, because the count from a previous setlist may + have the same value of an invalid setlist; so, we must + go all the way back to the first of them (if any) */ + for (j = 0; j < dest; j++) { + Instruction d = pt->code[dest-1-j]; + if (!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0)) break; + } + /* if 'j' is even, previous value is not a setlist (even if + it looks like one) */ + check((j&1) == 0); + } + } + break; + } + } + if (testAMode(op)) { + if (a == reg) last = pc; /* change register `a' */ + } + if (testTMode(op)) { + check(pc+2 < pt->sizecode); /* check skip */ + check(GET_OPCODE(pt->code[pc+1]) == OP_JMP); + } + switch (op) { + case OP_LOADBOOL: { + if (c == 1) { /* does it jump? */ + check(pc+2 < pt->sizecode); /* check its jump */ + check(GET_OPCODE(pt->code[pc+1]) != OP_SETLIST || + GETARG_C(pt->code[pc+1]) != 0); + } + break; + } + case OP_LOADNIL: { + if (a <= reg && reg <= b) + last = pc; /* set registers from `a' to `b' */ + break; + } + case OP_GETUPVAL: + case OP_SETUPVAL: { + check(b < pt->nups); + break; + } + case OP_GETGLOBAL: + case OP_SETGLOBAL: { + check(ttisstring(&pt->k[b])); + break; + } + case OP_SELF: { + checkreg(pt, a+1); + if (reg == a+1) last = pc; + break; + } + case OP_CONCAT: { + check(b < c); /* at least two operands */ + break; + } + case OP_TFORLOOP: { + check(c >= 1); /* at least one result (control variable) */ + checkreg(pt, a+2+c); /* space for results */ + if (reg >= a+2) last = pc; /* affect all regs above its base */ + break; + } + case OP_FORLOOP: + case OP_FORPREP: + checkreg(pt, a+3); + /* go through */ + case OP_JMP: { + int dest = pc+1+b; + /* not full check and jump is forward and do not skip `lastpc'? */ + if (reg != NO_REG && pc < dest && dest <= lastpc) + pc += b; /* do the jump */ + break; + } + case OP_CALL: + case OP_TAILCALL: { + if (b != 0) { + checkreg(pt, a+b-1); + } + c--; /* c = num. returns */ + if (c == LUA_MULTRET) { + check(checkopenop(pt, pc)); + } + else if (c != 0) + checkreg(pt, a+c-1); + if (reg >= a) last = pc; /* affect all registers above base */ + break; + } + case OP_RETURN: { + b--; /* b = num. returns */ + if (b > 0) checkreg(pt, a+b-1); + break; + } + case OP_SETLIST: { + if (b > 0) checkreg(pt, a + b); + if (c == 0) { + pc++; + check(pc < pt->sizecode - 1); + } + break; + } + case OP_CLOSURE: { + int nup, j; + check(b < pt->sizep); + nup = pt->p[b]->nups; + check(pc + nup < pt->sizecode); + for (j = 1; j <= nup; j++) { + OpCode op1 = GET_OPCODE(pt->code[pc + j]); + check(op1 == OP_GETUPVAL || op1 == OP_MOVE); + } + if (reg != NO_REG) /* tracing? */ + pc += nup; /* do not 'execute' these pseudo-instructions */ + break; + } + case OP_VARARG: { + check((pt->is_vararg & VARARG_ISVARARG) && + !(pt->is_vararg & VARARG_NEEDSARG)); + b--; + if (b == LUA_MULTRET) check(checkopenop(pt, pc)); + checkreg(pt, a+b-1); + break; + } + default: break; + } + } + return pt->code[last]; +} + +#undef check +#undef checkjump +#undef checkreg + +/* }====================================================== */ + + +int luaG_checkcode (const Proto *pt) { + return (symbexec(pt, pt->sizecode, NO_REG) != 0); +} + + +static const char *kname (Proto *p, int c) { + if (ISK(c) && ttisstring(&p->k[INDEXK(c)])) + return svalue(&p->k[INDEXK(c)]); + else + return "?"; +} + + +static const char *getobjname (lua_State *L, CallInfo *ci, int stackpos, + const char **name) { + if (isLua(ci)) { /* a Lua function? */ + Proto *p = ci_func(ci)->l.p; + int pc = currentpc(L, ci); + Instruction i; + *name = luaF_getlocalname(p, stackpos+1, pc); + if (*name) /* is a local? */ + return "local"; + i = symbexec(p, pc, stackpos); /* try symbolic execution */ + lua_assert(pc != -1); + switch (GET_OPCODE(i)) { + case OP_GETGLOBAL: { + int g = GETARG_Bx(i); /* global index */ + lua_assert(ttisstring(&p->k[g])); + *name = svalue(&p->k[g]); + return "global"; + } + case OP_MOVE: { + int a = GETARG_A(i); + int b = GETARG_B(i); /* move from `b' to `a' */ + if (b < a) + return getobjname(L, ci, b, name); /* get name for `b' */ + break; + } + case OP_GETTABLE: { + int k = GETARG_C(i); /* key index */ + *name = kname(p, k); + return "field"; + } + case OP_GETUPVAL: { + int u = GETARG_B(i); /* upvalue index */ + *name = p->upvalues ? getstr(p->upvalues[u]) : "?"; + return "upvalue"; + } + case OP_SELF: { + int k = GETARG_C(i); /* key index */ + *name = kname(p, k); + return "method"; + } + default: break; + } + } + return NULL; /* no useful name found */ +} + + +static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) { + Instruction i; + if ((isLua(ci) && ci->tailcalls > 0) || !isLua(ci - 1)) + return NULL; /* calling function is not Lua (or is unknown) */ + ci--; /* calling function */ + i = ci_func(ci)->l.p->code[currentpc(L, ci)]; + if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL || + GET_OPCODE(i) == OP_TFORLOOP) + return getobjname(L, ci, GETARG_A(i), name); + else + return NULL; /* no useful name can be found */ +} + + +/* only ANSI way to check whether a pointer points to an array */ +static int isinstack (CallInfo *ci, const TValue *o) { + StkId p; + for (p = ci->base; p < ci->top; p++) + if (o == p) return 1; + return 0; +} + + +void luaG_typeerror (lua_State *L, const TValue *o, const char *op) { + const char *name = NULL; + const char *t = luaT_typenames[ttype(o)]; + const char *kind = (isinstack(L->ci, o)) ? + getobjname(L, L->ci, cast_int(o - L->base), &name) : + NULL; + if (kind) + luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)", + op, kind, name, t); + else + luaG_runerror(L, "attempt to %s a %s value", op, t); +} + + +void luaG_concaterror (lua_State *L, StkId p1, StkId p2) { + if (ttisstring(p1) || ttisnumber(p1)) p1 = p2; + lua_assert(!ttisstring(p1) && !ttisnumber(p1)); + luaG_typeerror(L, p1, "concatenate"); +} + + +void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) { + TValue temp; + if (luaV_tonumber(p1, &temp) == NULL) + p2 = p1; /* first operand is wrong */ + luaG_typeerror(L, p2, "perform arithmetic on"); +} + + +int luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) { + const char *t1 = luaT_typenames[ttype(p1)]; + const char *t2 = luaT_typenames[ttype(p2)]; + if (t1[2] == t2[2]) + luaG_runerror(L, "attempt to compare two %s values", t1); + else + luaG_runerror(L, "attempt to compare %s with %s", t1, t2); + return 0; +} + + +static void addinfo (lua_State *L, const char *msg) { + CallInfo *ci = L->ci; + if (isLua(ci)) { /* is Lua code? */ + char buff[LUA_IDSIZE]; /* add file:line information */ + int line = currentline(L, ci); + luaO_chunkid(buff, getstr(getluaproto(ci)->source), LUA_IDSIZE); + luaO_pushfstring(L, "%s:%d: %s", buff, line, msg); + } +} + + +void luaG_errormsg (lua_State *L) { + if (L->errfunc != 0) { /* is there an error handling function? */ + StkId errfunc = restorestack(L, L->errfunc); + if (!ttisfunction(errfunc)) luaD_throw(L, LUA_ERRERR); + setobjs2s(L, L->top, L->top - 1); /* move argument */ + setobjs2s(L, L->top - 1, errfunc); /* push function */ + incr_top(L); + luaD_call(L, L->top - 2, 1); /* call it */ + } + luaD_throw(L, LUA_ERRRUN); +} + + +void luaG_runerror (lua_State *L, const char *fmt, ...) { + va_list argp; + va_start(argp, fmt); + addinfo(L, luaO_pushvfstring(L, fmt, argp)); + va_end(argp); + luaG_errormsg(L); +} + |