diff options
Diffstat (limited to 'lua/ldebug.c')
-rw-r--r-- | lua/ldebug.c | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/lua/ldebug.c b/lua/ldebug.c new file mode 100644 index 000000000..aaff167cc --- /dev/null +++ b/lua/ldebug.c @@ -0,0 +1,585 @@ +/* +** $Id: ldebug.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $ +** Debug Interface +** See Copyright Notice in lua.h +*/ + + +#include <stdlib.h> +#include <string.h> + +#define ldebug_c + +#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 (CallInfo *ci, const char **name); + + +#define isLua(ci) (!((ci)->state & CI_C)) + + +static int currentpc (CallInfo *ci) { + if (!isLua(ci)) return -1; /* function is not a Lua function? */ + if (ci->state & CI_HASFRAME) /* function has a frame? */ + ci->u.l.savedpc = *ci->u.l.pc; /* use `pc' from there */ + /* function's pc is saved */ + return pcRel(ci->u.l.savedpc, ci_func(ci)->l.p); +} + + +static int currentline (CallInfo *ci) { + int pc = currentpc(ci); + if (pc < 0) + return -1; /* only active lua functions have current-line information */ + else + return getline(ci_func(ci)->l.p, pc); +} + + +void luaG_inithooks (lua_State *L) { + CallInfo *ci; + for (ci = L->ci; ci != L->base_ci; ci--) /* update all `savedpc's */ + currentpc(ci); + L->hookinit = 1; +} + + +/* +** 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(lu_byte, mask); + L->hookinit = 0; + 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 (!(ci->state & CI_C)) /* Lua function? */ + level -= ci->u.l.tailcalls; /* skip lost tail calls */ + } + if (level > 0 || ci == L->base_ci) status = 0; /* there is no such level */ + else if (level < 0) { /* level is of a lost tail call */ + status = 1; + ar->i_ci = 0; + } + else { + status = 1; + ar->i_ci = ci - L->base_ci; + } + lua_unlock(L); + return status; +} + + +static Proto *getluaproto (CallInfo *ci) { + return (isLua(ci) ? ci_func(ci)->l.p : NULL); +} + + +LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) { + const char *name; + CallInfo *ci; + Proto *fp; + lua_lock(L); + name = NULL; + ci = L->base_ci + ar->i_ci; + fp = getluaproto(ci); + if (fp) { /* is a Lua function? */ + name = luaF_getlocalname(fp, n, currentpc(ci)); + if (name) + luaA_pushobject(L, ci->base+(n-1)); /* push value */ + } + lua_unlock(L); + return name; +} + + +LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) { + const char *name; + CallInfo *ci; + Proto *fp; + lua_lock(L); + name = NULL; + ci = L->base_ci + ar->i_ci; + fp = getluaproto(ci); + L->top--; /* pop new value */ + if (fp) { /* is a Lua function? */ + name = luaF_getlocalname(fp, n, currentpc(ci)); + if (!name || name[0] == '(') /* `(' starts private locals */ + name = NULL; + else + setobjs2s(ci->base+(n-1), L->top); + } + lua_unlock(L); + return name; +} + + +static void funcinfo (lua_Debug *ar, StkId func) { + Closure *cl = clvalue(func); + if (cl->c.isC) { + ar->source = "=[C]"; + ar->linedefined = -1; + ar->what = "C"; + } + else { + ar->source = getstr(cl->l.p->source); + ar->linedefined = cl->l.p->lineDefined; + ar->what = (ar->linedefined == 0) ? "main" : "Lua"; + } + luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE); +} + + +static const char *travglobals (lua_State *L, const TObject *o) { + Table *g = hvalue(gt(L)); + int i = sizenode(g); + while (i--) { + Node *n = gnode(g, i); + if (luaO_rawequalObj(o, gval(n)) && ttisstring(gkey(n))) + return getstr(tsvalue(gkey(n))); + } + return NULL; +} + + +static void info_tailcall (lua_State *L, lua_Debug *ar) { + ar->name = ar->namewhat = ""; + ar->what = "tail"; + ar->linedefined = ar->currentline = -1; + ar->source = "=(tail call)"; + luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE); + ar->nups = 0; + setnilvalue(L->top); +} + + +static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar, + StkId f, CallInfo *ci) { + int status = 1; + for (; *what; what++) { + switch (*what) { + case 'S': { + funcinfo(ar, f); + break; + } + case 'l': { + ar->currentline = (ci) ? currentline(ci) : -1; + break; + } + case 'u': { + ar->nups = clvalue(f)->c.nupvalues; + break; + } + case 'n': { + ar->namewhat = (ci) ? getfuncname(ci, &ar->name) : NULL; + if (ar->namewhat == NULL) { + /* try to find a global name */ + if ((ar->name = travglobals(L, f)) != NULL) + ar->namewhat = "global"; + else ar->namewhat = ""; /* not found */ + } + break; + } + case 'f': { + setobj2s(L->top, f); + break; + } + default: status = 0; /* invalid option */ + } + } + return status; +} + + +LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) { + int status = 1; + lua_lock(L); + if (*what == '>') { + StkId f = L->top - 1; + if (!ttisfunction(f)) + luaG_runerror(L, "value for `lua_getinfo' is not a function"); + status = auxgetinfo(L, what + 1, ar, f, NULL); + L->top--; /* pop function */ + } + else if (ar->i_ci != 0) { /* no tail call? */ + CallInfo *ci = L->base_ci + ar->i_ci; + lua_assert(ttisfunction(ci->base - 1)); + status = auxgetinfo(L, what, ar, ci->base - 1, ci); + } + else + info_tailcall(L, ar); + if (strchr(what, 'f')) incr_top(L); + 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->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0); + lua_assert(pt->numparams+pt->is_vararg <= pt->maxstacksize); + check(GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN); + return 1; +} + + +static int checkopenop (const Proto *pt, int pc) { + Instruction i = pt->code[pc+1]; + switch (GET_OPCODE(i)) { + case OP_CALL: + case OP_TAILCALL: + case OP_RETURN: { + check(GETARG_B(i) == 0); + return 1; + } + case OP_SETLISTO: return 1; + default: return 0; /* invalid instruction after an open call */ + } +} + + +static int checkRK (const Proto *pt, int r) { + return (r < pt->maxstacksize || (r >= MAXSTACK && r-MAXSTACK < pt->sizek)); +} + + +static Instruction luaG_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++) { + const Instruction i = pt->code[pc]; + OpCode op = GET_OPCODE(i); + int a = GETARG_A(i); + int b = 0; + int c = 0; + checkreg(pt, a); + switch (getOpMode(op)) { + case iABC: { + b = GETARG_B(i); + c = GETARG_C(i); + if (testOpMode(op, OpModeBreg)) { + checkreg(pt, b); + } + else if (testOpMode(op, OpModeBrk)) + check(checkRK(pt, b)); + if (testOpMode(op, OpModeCrk)) + check(checkRK(pt, c)); + break; + } + case iABx: { + b = GETARG_Bx(i); + if (testOpMode(op, OpModeK)) check(b < pt->sizek); + break; + } + case iAsBx: { + b = GETARG_sBx(i); + break; + } + } + if (testOpMode(op, OpModesetA)) { + if (a == reg) last = pc; /* change register `a' */ + } + if (testOpMode(op, OpModeT)) { + check(pc+2 < pt->sizecode); /* check skip */ + check(GET_OPCODE(pt->code[pc+1]) == OP_JMP); + } + switch (op) { + case OP_LOADBOOL: { + check(c == 0 || pc+2 < pt->sizecode); /* check its jump */ + 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: { + /* `c' is a register, and at least two operands */ + check(c < MAXSTACK && b < c); + break; + } + case OP_TFORLOOP: + checkreg(pt, a+c+5); + if (reg >= a) last = pc; /* affect all registers above base */ + /* go through */ + case OP_FORLOOP: + checkreg(pt, a+2); + /* go through */ + case OP_JMP: { + int dest = pc+1+b; + check(0 <= dest && dest < pt->sizecode); + /* 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: { + checkreg(pt, a + (b&(LFIELDS_PER_FLUSH-1)) + 1); + break; + } + case OP_CLOSURE: { + int nup; + check(b < pt->sizep); + nup = pt->p[b]->nups; + check(pc + nup < pt->sizecode); + for (; nup>0; nup--) { + OpCode op1 = GET_OPCODE(pt->code[pc+nup]); + check(op1 == OP_GETUPVAL || op1 == OP_MOVE); + } + break; + } + default: break; + } + } + return pt->code[last]; +} + +#undef check +#undef checkjump +#undef checkreg + +/* }====================================================== */ + + +int luaG_checkcode (const Proto *pt) { + return luaG_symbexec(pt, pt->sizecode, NO_REG); +} + + +static const char *kname (Proto *p, int c) { + c = c - MAXSTACK; + if (c >= 0 && ttisstring(&p->k[c])) + return svalue(&p->k[c]); + else + return "?"; +} + + +static const char *getobjname (CallInfo *ci, int stackpos, const char **name) { + if (isLua(ci)) { /* a Lua function? */ + Proto *p = ci_func(ci)->l.p; + int pc = currentpc(ci); + Instruction i; + *name = luaF_getlocalname(p, stackpos+1, pc); + if (*name) /* is a local? */ + return "local"; + i = luaG_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(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_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 (CallInfo *ci, const char **name) { + Instruction i; + if ((isLua(ci) && ci->u.l.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(ci)]; + if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL) + return getobjname(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 TObject *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 TObject *o, const char *op) { + const char *name = NULL; + const char *t = luaT_typenames[ttype(o)]; + const char *kind = (isinstack(L->ci, o)) ? + getobjname(L->ci, o - L->base, &name) : NULL; + if (kind) + luaG_runerror(L, "attempt to %s %s `%s' (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)) p1 = p2; + lua_assert(!ttisstring(p1)); + luaG_typeerror(L, p1, "concatenate"); +} + + +void luaG_aritherror (lua_State *L, const TObject *p1, const TObject *p2) { + TObject 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 TObject *p1, const TObject *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(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->top, L->top - 1); /* move argument */ + setobjs2s(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); +} + |