/*** $Id: ldblib.c,v 1.104 2005/12/29 15:32:11 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#define LUA_LIB#include "lua.h"#include "lauxlib.h"#include "lualib.h"static int db_getregistry (lua_State *L) {  lua_pushvalue(L, LUA_REGISTRYINDEX);  return 1;}static int db_getmetatable (lua_State *L) {  luaL_checkany(L, 1);  if (!lua_getmetatable(L, 1)) {    lua_pushnil(L);  /* no metatable */  }  return 1;}static int db_setmetatable (lua_State *L) {  int t = lua_type(L, 2);  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,                    "nil or table expected");  lua_settop(L, 2);  lua_pushboolean(L, lua_setmetatable(L, 1));  return 1;}static int db_getfenv (lua_State *L) {  lua_getfenv(L, 1);  return 1;}static int db_setfenv (lua_State *L) {  luaL_checktype(L, 2, LUA_TTABLE);  lua_settop(L, 2);  if (lua_setfenv(L, 1) == 0)    luaL_error(L, LUA_QL("setfenv")                  " cannot change environment of given object");  return 1;}static void settabss (lua_State *L, const char *i, const char *v) {  lua_pushstring(L, v);  lua_setfield(L, -2, i);}static void settabsi (lua_State *L, const char *i, int v) {  lua_pushinteger(L, v);  lua_setfield(L, -2, i);}static lua_State *getthread (lua_State *L, int *arg) {  if (lua_isthread(L, 1)) {    *arg = 1;    return lua_tothread(L, 1);  }  else {    *arg = 0;    return L;  }}static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {  if (L == L1) {    lua_pushvalue(L, -2);    lua_remove(L, -3);  }  else    lua_xmove(L1, L, 1);  lua_setfield(L, -2, fname);}static int db_getinfo (lua_State *L) {  lua_Debug ar;  int arg;  lua_State *L1 = getthread(L, &arg);  const char *options = luaL_optstring(L, arg+2, "flnSu");  if (lua_isnumber(L, arg+1)) {    if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {      lua_pushnil(L);  /* level out of range */      return 1;    }  }  else if (lua_isfunction(L, arg+1)) {    lua_pushfstring(L, ">%s", options);    options = lua_tostring(L, -1);    lua_pushvalue(L, arg+1);    lua_xmove(L, L1, 1);  }  else    return luaL_argerror(L, arg+1, "function or level expected");  if (!lua_getinfo(L1, options, &ar))    return luaL_argerror(L, arg+2, "invalid option");  lua_createtable(L, 0, 2);  if (strchr(options, 'S')) {    settabss(L, "source", ar.source);    settabss(L, "short_src", ar.short_src);    settabsi(L, "linedefined", ar.linedefined);    settabsi(L, "lastlinedefined", ar.lastlinedefined);    settabss(L, "what", ar.what);  }  if (strchr(options, 'l'))    settabsi(L, "currentline", ar.currentline);  if (strchr(options, 'u'))    settabsi(L, "nups", ar.nups);  if (strchr(options, 'n')) {    settabss(L, "name", ar.name);    settabss(L, "namewhat", ar.namewhat);  }  if (strchr(options, 'L'))    treatstackoption(L, L1, "activelines");  if (strchr(options, 'f'))    treatstackoption(L, L1, "func");  return 1;  /* return table */}    static int db_getlocal (lua_State *L) {  int arg;  lua_State *L1 = getthread(L, &arg);  lua_Debug ar;  const char *name;  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */    return luaL_argerror(L, arg+1, "level out of range");  name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));  if (name) {    lua_xmove(L1, L, 1);    lua_pushstring(L, name);    lua_pushvalue(L, -2);    return 2;  }  else {    lua_pushnil(L);    return 1;  }}static int db_setlocal (lua_State *L) {  int arg;  lua_State *L1 = getthread(L, &arg);  lua_Debug ar;  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */    return luaL_argerror(L, arg+1, "level out of range");  luaL_checkany(L, arg+3);  lua_settop(L, arg+3);  lua_xmove(L, L1, 1);  lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+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 db_getupvalue (lua_State *L) {  return auxupvalue(L, 1);}static int db_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);  lua_pushlightuserdata(L, L);  lua_rawget(L, -2);  if (lua_isfunction(L, -1)) {    lua_pushstring(L, hooknames[(int)ar->event]);    if (ar->currentline >= 0)      lua_pushinteger(L, ar->currentline);    else lua_pushnil(L);    lua_assert(lua_getinfo(L, "lS", ar));    lua_call(L, 2, 0);  }}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 void gethooktable (lua_State *L) {  lua_pushlightuserdata(L, (void *)&KEY_HOOK);  lua_rawget(L, LUA_REGISTRYINDEX);  if (!lua_istable(L, -1)) {    lua_pop(L, 1);    lua_createtable(L, 0, 1);    lua_pushlightuserdata(L, (void *)&KEY_HOOK);    lua_pushvalue(L, -2);    lua_rawset(L, LUA_REGISTRYINDEX);  }}static int db_sethook (lua_State *L) {  int arg;  lua_State *L1 = getthread(L, &arg);  if (lua_isnoneornil(L, arg+1)) {    lua_settop(L, arg+1);    lua_sethook(L1, NULL, 0, 0);  /* turn off hooks */  }  else {    const char *smask = luaL_checkstring(L, arg+2);    int count = luaL_optint(L, arg+3, 0);    luaL_checktype(L, arg+1, LUA_TFUNCTION);    lua_sethook(L1, hookf, makemask(smask, count), count);  }  gethooktable(L1);  lua_pushlightuserdata(L1, L1);  lua_pushvalue(L, arg+1);  lua_xmove(L, L1, 1);  lua_rawset(L1, -3);  /* set new hook */  lua_pop(L1, 1);  /* remove hook table */  return 0;}static int db_gethook (lua_State *L) {  int arg;  lua_State *L1 = getthread(L, &arg);  char buff[5];  int mask = lua_gethookmask(L1);  lua_Hook hook = lua_gethook(L1);  if (hook != NULL && hook != hookf)  /* external hook? */    lua_pushliteral(L, "external hook");  else {    gethooktable(L1);    lua_pushlightuserdata(L1, L1);    lua_rawget(L1, -2);   /* get hook */    lua_remove(L1, -2);  /* remove hook table */    lua_xmove(L1, L, 1);  }  lua_pushstring(L, unmakemask(mask, buff));  lua_pushinteger(L, lua_gethookcount(L1));  return 3;}static int db_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;    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||        lua_pcall(L, 0, 0, 0)) {      fputs(lua_tostring(L, -1), stderr);      fputs("\n", stderr);    }    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 db_errorfb (lua_State *L) {  int level;  int firstpart = 1;  /* still before eventual `...' */  int arg;  lua_State *L1 = getthread(L, &arg);  lua_Debug ar;  if (lua_isnumber(L, arg+2)) {    level = (int)lua_tointeger(L, arg+2);    lua_pop(L, 1);  }  else    level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */  if (lua_gettop(L) == arg)    lua_pushliteral(L, "");  else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */  else lua_pushliteral(L, "\n");  lua_pushliteral(L, "stack traceback:");  while (lua_getstack(L1, level++, &ar)) {    if (level > LEVELS1 && firstpart) {      /* no more than `LEVELS2' more levels? */      if (!lua_getstack(L1, level+LEVELS2, &ar))        level--;  /* keep going */      else {        lua_pushliteral(L, "\n\t...");  /* too many levels */        while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */          level++;      }      firstpart = 0;      continue;    }    lua_pushliteral(L, "\n\t");    lua_getinfo(L1, "Snl", &ar);    lua_pushfstring(L, "%s:", ar.short_src);    if (ar.currentline > 0)      lua_pushfstring(L, "%d:", ar.currentline);    if (*ar.namewhat != '\0')  /* is there a name? */        lua_pushfstring(L, " in function " LUA_QS, ar.name);    else {      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) - arg);  }  lua_concat(L, lua_gettop(L) - arg);  return 1;}static const luaL_Reg dblib[] = {  {"debug", db_debug},  {"getfenv", db_getfenv},  {"gethook", db_gethook},  {"getinfo", db_getinfo},  {"getlocal", db_getlocal},  {"getregistry", db_getregistry},  {"getmetatable", db_getmetatable},  {"getupvalue", db_getupvalue},  {"setfenv", db_setfenv},  {"sethook", db_sethook},  {"setlocal", db_setlocal},  {"setmetatable", db_setmetatable},  {"setupvalue", db_setupvalue},  {"traceback", db_errorfb},  {NULL, NULL}};LUALIB_API int luaopen_debug (lua_State *L) {  luaL_register(L, LUA_DBLIBNAME, dblib);  return 1;}