ldblib.c
(5.0.3)
/*
** $Id: ldblib.c,v 1.80 2003/04/03 13:35:34 roberto Exp $
** Interface from Lua to its debug API
** See Copyright Notice in lua.h
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define ldblib_c
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
static void settabss (lua_State *L, const char *i, const char *v) {
lua_pushstring(L, i);
lua_pushstring(L, v);
lua_rawset(L, -3);
}
static void settabsi (lua_State *L, const char *i, int v) {
lua_pushstring(L, i);
lua_pushnumber(L, (lua_Number)v);
lua_rawset(L, -3);
}
static int getinfo (lua_State *L) {
lua_Debug ar;
const char *options = luaL_optstring(L, 2, "flnSu");
if (lua_isnumber(L, 1)) {
if (!lua_getstack(L, (int)(lua_tonumber(L, 1)), &ar)) {
lua_pushnil(L); /* level out of range */
return 1;
}
}
else if (lua_isfunction(L, 1)) {
lua_pushfstring(L, ">%s", options);
options = lua_tostring(L, -1);
lua_pushvalue(L, 1);
}
else
return luaL_argerror(L, 1, "function or level expected");
if (!lua_getinfo(L, options, &ar))
return luaL_argerror(L, 2, "invalid option");
lua_newtable(L);
for (; *options; options++) {
switch (*options) {
case 'S':
settabss(L, "source", ar.source);
settabss(L, "short_src", ar.short_src);
settabsi(L, "linedefined", ar.linedefined);
settabss(L, "what", ar.what);
break;
case 'l':
settabsi(L, "currentline", ar.currentline);
break;
case 'u':
settabsi(L, "nups", ar.nups);
break;
case 'n':
settabss(L, "name", ar.name);
settabss(L, "namewhat", ar.namewhat);
break;
case 'f':
lua_pushliteral(L, "func");
lua_pushvalue(L, -3);
lua_rawset(L, -3);
break;
}
}
return 1; /* return table */
}
static int getlocal (lua_State *L) {
lua_Debug ar;
const char *name;
if (!lua_getstack(L, luaL_checkint(L, 1), &ar)) /* level out of range? */
return luaL_argerror(L, 1, "level out of range");
name = lua_getlocal(L, &ar, luaL_checkint(L, 2));
if (name) {
lua_pushstring(L, name);
lua_pushvalue(L, -2);
return 2;
}
else {
lua_pushnil(L);
return 1;
}
}
static int setlocal (lua_State *L) {
lua_Debug ar;
if (!lua_getstack(L, luaL_checkint(L, 1), &ar)) /* level out of range? */
return luaL_argerror(L, 1, "level out of range");
luaL_checkany(L, 3);
lua_pushstring(L, lua_setlocal(L, &ar, luaL_checkint(L, 2)));
return 1;
}
static int auxupvalue (lua_State *L, int get) {
const char *name;
int n = luaL_checkint(L, 2);
luaL_checktype(L, 1, LUA_TFUNCTION);
if (lua_iscfunction(L, 1)) return 0; /* cannot touch C upvalues from Lua */
name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
if (name == NULL) return 0;
lua_pushstring(L, name);
lua_insert(L, -(get+1));
return get + 1;
}
static int getupvalue (lua_State *L) {
return auxupvalue(L, 1);
}
static int setupvalue (lua_State *L) {
luaL_checkany(L, 3);
return auxupvalue(L, 0);
}
static const char KEY_HOOK = 'h';
static void hookf (lua_State *L, lua_Debug *ar) {
static const char *const hooknames[] =
{"call", "return", "line", "count", "tail return"};
lua_pushlightuserdata(L, (void *)&KEY_HOOK);
lua_rawget(L, LUA_REGISTRYINDEX);
if (lua_isfunction(L, -1)) {
lua_pushstring(L, hooknames[(int)ar->event]);
if (ar->currentline >= 0)
lua_pushnumber(L, (lua_Number)ar->currentline);
else lua_pushnil(L);
lua_assert(lua_getinfo(L, "lS", ar));
lua_call(L, 2, 0);
}
else
lua_pop(L, 1); /* pop result from gettable */
}
static int makemask (const char *smask, int count) {
int mask = 0;
if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
if (strchr(smask, 'r')) mask |= LUA_MASKRET;
if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
if (count > 0) mask |= LUA_MASKCOUNT;
return mask;
}
static char *unmakemask (int mask, char *smask) {
int i = 0;
if (mask & LUA_MASKCALL) smask[i++] = 'c';
if (mask & LUA_MASKRET) smask[i++] = 'r';
if (mask & LUA_MASKLINE) smask[i++] = 'l';
smask[i] = '\0';
return smask;
}
static int sethook (lua_State *L) {
if (lua_isnoneornil(L, 1)) {
lua_settop(L, 1);
lua_sethook(L, NULL, 0, 0); /* turn off hooks */
}
else {
const char *smask = luaL_checkstring(L, 2);
int count = luaL_optint(L, 3, 0);
luaL_checktype(L, 1, LUA_TFUNCTION);
lua_sethook(L, hookf, makemask(smask, count), count);
}
lua_pushlightuserdata(L, (void *)&KEY_HOOK);
lua_pushvalue(L, 1);
lua_rawset(L, LUA_REGISTRYINDEX); /* set new hook */
return 0;
}
static int gethook (lua_State *L) {
char buff[5];
int mask = lua_gethookmask(L);
lua_Hook hook = lua_gethook(L);
if (hook != NULL && hook != hookf) /* external hook? */
lua_pushliteral(L, "external hook");
else {
lua_pushlightuserdata(L, (void *)&KEY_HOOK);
lua_rawget(L, LUA_REGISTRYINDEX); /* get hook */
}
lua_pushstring(L, unmakemask(mask, buff));
lua_pushnumber(L, (lua_Number)lua_gethookcount(L));
return 3;
}
static int debug (lua_State *L) {
for (;;) {
char buffer[250];
fputs("lua_debug> ", stderr);
if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
strcmp(buffer, "cont\n") == 0)
return 0;
lua_dostring(L, buffer);
lua_settop(L, 0); /* remove eventual returns */
}
}
#define LEVELS1 12 /* size of the first part of the stack */
#define LEVELS2 10 /* size of the second part of the stack */
static int errorfb (lua_State *L) {
int level = 1; /* skip level 0 (it's this function) */
int firstpart = 1; /* still before eventual `...' */
lua_Debug ar;
if (lua_gettop(L) == 0)
lua_pushliteral(L, "");
else if (!lua_isstring(L, 1)) return 1; /* no string message */
else lua_pushliteral(L, "\n");
lua_pushliteral(L, "stack traceback:");
while (lua_getstack(L, level++, &ar)) {
if (level > LEVELS1 && firstpart) {
/* no more than `LEVELS2' more levels? */
if (!lua_getstack(L, level+LEVELS2, &ar))
level--; /* keep going */
else {
lua_pushliteral(L, "\n\t..."); /* too many levels */
while (lua_getstack(L, level+LEVELS2, &ar)) /* find last levels */
level++;
}
firstpart = 0;
continue;
}
lua_pushliteral(L, "\n\t");
lua_getinfo(L, "Snl", &ar);
lua_pushfstring(L, "%s:", ar.short_src);
if (ar.currentline > 0)
lua_pushfstring(L, "%d:", ar.currentline);
switch (*ar.namewhat) {
case 'g': /* global */
case 'l': /* local */
case 'f': /* field */
case 'm': /* method */
lua_pushfstring(L, " in function `%s'", ar.name);
break;
default: {
if (*ar.what == 'm') /* main? */
lua_pushfstring(L, " in main chunk");
else if (*ar.what == 'C' || *ar.what == 't')
lua_pushliteral(L, " ?"); /* C function or tail call */
else
lua_pushfstring(L, " in function <%s:%d>",
ar.short_src, ar.linedefined);
}
}
lua_concat(L, lua_gettop(L));
}
lua_concat(L, lua_gettop(L));
return 1;
}
static const luaL_reg dblib[] = {
{"getlocal", getlocal},
{"getinfo", getinfo},
{"gethook", gethook},
{"getupvalue", getupvalue},
{"sethook", sethook},
{"setlocal", setlocal},
{"setupvalue", setupvalue},
{"debug", debug},
{"traceback", errorfb},
{NULL, NULL}
};
LUALIB_API int luaopen_debug (lua_State *L) {
luaL_openlib(L, LUA_DBLIBNAME, dblib, 0);
lua_pushliteral(L, "_TRACEBACK");
lua_pushcfunction(L, errorfb);
lua_settable(L, LUA_GLOBALSINDEX);
return 1;
}